WorldWideScience

Sample records for tetraethyl lead

  1. Group and insidious tetraethyl lead poisoning occurred in industry of plastic weaving: a case report.

    Science.gov (United States)

    Zhang, Feng; Bai, Ying; Zhu, Baoli; Zhu, Wenjing; Ye, Mingxian

    2016-05-01

    Tetraethyl lead (TEL) poisoning has declined sharply with decreasing consumption of gasoil and other chemicals contained TEL. Here we reported group TEL poisoning in the plastic weaving factory. We investigated 16 cases with the typical nerves disorder which is similar to organotin poisoning, and the result suggested that the poisoning may cause by applied "white oil" contented TEL. Despite its rareness, our cases emphasize that clinicians should pay attention to the difference from the treatment of organic tin poisoning.

  2. Case-control study of cancer risk in tetraethyl lead manufacturing.

    Science.gov (United States)

    Fayerweather, W E; Karns, M E; Nuwayhid, I A; Nelson, T J

    1997-01-01

    A case-control study was conducted to investigate the relative risk of cancer detection among Du Pont employees who worked in a tetraethyl lead (TEL) manufacturing area. The study's objective was to determine whether the employees' risk of developing or dying from cancer was associated with occupational exposure to TEL. All malignant neoplasms detected in the active and pensioned employee population during the period 1956-1987 were studied. TEL exposure was estimated by the following measures: ever employed in the TEL area, years of employment in TEL, TEL exposure rank, and the TEL cumulative exposure index. TEL manufacturing exposed employees to both organic and inorganic lead compounds. Because the underlying data did not permit the exposure assessment to distinguish between organic and inorganic lead, the TEL exposure measures reflect exposure to the TEL manufacturing process itself. The effects of latency, cigarette smoking habits, and exposures to other known or suspected carcinogens at the plant were also assessed. A strong association was observed between exposure to the TEL manufacturing process and rectal cancer (the odds ratio was 3.7 with 90% confidence limits of 1.3-10.2 for the analysis of ever/never exposed to TEL). An exposure-response relationship was noted with a fourfold elevation in the odds ratio at the high-very high cumulative exposure level. These patterns were even more pronounced after assuming a 10 year latency. Similar results were obtained for cancers of the sigmoid colon. These findings suggest that exposure to the TEL manufacturing process may have played a causal role in the colorectal cancer experience at the plant. This position is supported by the graded exposure-response relationships, the consistency of the results across exposure measures, the specificity of the health outcome (i.e., colorectal cancer), and the strength of the association. However, the evidence for causality is not compelling. This is the first report of an

  3. 40 CFR 721.9928 - Urea, tetraethyl-.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Urea, tetraethyl-. 721.9928 Section... Substances § 721.9928 Urea, tetraethyl-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as urea, tetraethyl- (PMN P-94-1017; CAS No. 1187-03-7) is...

  4. Silica Xerogel Obtained by Ultrashort Laser Irradiation of Tetraethyl Orthosilicate.

    Science.gov (United States)

    Sansone, Maria; De Bonis, Angela; Galasso, Agostino; Santagata, Antonio; Teghil, Roberto

    2017-05-05

    The formation of an opaque solid foam was induced by the direct interaction between tetraethyl orthosilicate (TEOS) and an ultrashort femtosecond laser source(Nd:glass, 527 nm, 10 Hz, 250 fs). The product, which resulted to be a silica xerogel, was characterized by different techniques. In particular, information about the morphology was obtained by scanning and transmission electron microscopy (SEM and TEM), while the presence of different functional groups was studied through IR measurements. Since the properties of this kind of material can be improved by functionalizing it with metal nanoparticles, a palladium metal target was ablated in liquid TEOS. TEM images show that palladium was present in the form of nanoparticles and EDX measurements confirm the presence of the metal inside the silica network. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. New Rare Earth Antiknock Additives that are Potential Substitutes for Tetraethyl Lead

    Science.gov (United States)

    1974-12-01

    1941); (Available from Univ. Microfilms, Ann Arbor, Mich. as Thesis No. 260). 29. Fernelius, W.C., Private communication to R.E. Sievers, May 1974...30. Tullock, A.P. and Weenink, R.O., Chem. Comnm., 225, (1966). 31. Barber, H.N. and Netting, A.G., Phytochemistry , 7, 2089 (1968). 32. Ross, W.D. and...Sievers, R.E., unpublished data. 33. Jackson. L.L. Phytochemistry , 10, 487 (1971). 55 34. Horn, D.H.S. and Lamberton, J.A., Chem. and Ind., 2036

  6. Problem of lead in petrol: The effect of triethyl lead

    Energy Technology Data Exchange (ETDEWEB)

    Roederer, G.

    1985-10-01

    Triethyl lead is a highly toxic derivate of the anti-knock agent tetraethyl lead. Contrary to anorganic lead compounds triethyl lead causes serious disorders in the central nervous system of poisoned mammals leading to dramatic mental changes. Triethyl lead destroys microtubuli in the cells of plants and animals. It is assumed that the neurotoxic effect of triethyl lead is caused by its interacting with the microtubuli of the nerves (neurotubuli) and their subsequent destruction.

  7. Synthesis of tetraethyl pyrophosphate (TEPP): from physician Abbot and pharmacist Riegel to chemist Nylen.

    Science.gov (United States)

    Petroianu, G A

    2015-06-01

    Tetraethyl pyrophosphate (TEPP) made history not only as the first man-made organophosphate cholinesterase inhibitor but also as a most successful commercial product traded under a good number of names. The substance was first synthesized by a Russian chemist, Wladimir Petrovich Moshnin, while studying in Paris as an eleve (student) of Wurtz. The synthesis was soon thereafter repeated and reported to the Academy of Sciences by Philippe de Clermont, another student of Wurtz, who acknowledged the earlier work of Moshnin. Holmstedt in his chapter dealing with the beginnings of organophosphate chemistry in Koelle's Textbook Cholinesterases and Anticholinesterase Agents concluded his remarks by noting that after the initial synthesis by Moshnin and de Clermont, over the years, a good half-a-dozen of other pharmacists and chemists also managed the feat (of synthesizing TEPP). This led to my attempts at identifying those involved in the synthesis of TEPP. The compiled list turned out to be quite long: Abbot (1879), Riegel (1896), Cavalier (1906), Rosenheim A, Stadler & Jacobsohn (1906), Rosenheim & Pritze (1908), Balareff (1914), Nylen (1930), Arbusow & Arbusow (1931), Schrader (1938), Woodstock (1946) and Toy (1948). This report while summarizing the synthetic approach used in obtaining TEPP by the respective scientists mainly attempts to shed light on the life of the less known pharmacists and chemists involved in the synthesis of TEPP. The focus is on the pre-industrial synthesis period ending with Nylen largely because details on the Arbusow family, as well as on Schrader and Toy are fairly well known or have recently been described.

  8. LEAD POISONING IN ANCIENT ROME 1. INTRODUCTION

    African Journals Online (AJOL)

    of organic lead compounds such as tetra-ethyl lead, found in modern .... organic bone matrix. An adjustment formula taking the age of the adult into consideration is therefore necessary. There is no difference in bone lead content between men and women ... architect, Vitruvius (viii.6.10, 11), tells us that water from clay pipes.

  9. 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 ...

  10. 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 ...

  11. Lead and the skin

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B.R.; Moore, M.R.; Hunter, J.A.A.

    1975-01-01

    The increasing use of lead will continue to give rise to problems of toxicity. Protective measures have resulted in florid lead poisoning becoming rare. Attention has recently turned to the possibility of prolonged exposure to low doses of lead causing morbidity in the absence of the classical clinical features of poisoning. Lead is absorbed mostly through the lungs and gastrointestinal tract. Some is also absorbed through the skin but with inorganic compounds the amount is small. Shortly after the most widely used compound, tetraethyl lead, was first manufactured, cases of toxicity began to occur. Manufacture was forbidden until plant design produced greater safety. Significant absorption can occur through the skin. The hazard to those handling leaded gasoline in a normal manner is probably small, mainly because 95 percent of a dose applied to the open skin surface evaporates. Hair has been used as a biopsy material to assess lead exposure. The biological effects of lead poisoning are discussed, including the synergistic effects of lead and agents provoking porphyria.

  12. Chronicling a century of lead pollution in Mexico: stable lead isotopic composition analyses of dated sediment cores.

    Science.gov (United States)

    Soto-Jimenez, Martin F; Hibdon, Sharon A; Rankin, Charley W; Aggarawl, Jugdeep; Ruiz-Fernandez, A Carolina; Paez-Osuna, Federico; Flegal, A Russell

    2006-02-01

    Analyses of lead isotopic compositions (204Pb, 206Pb, 207Pb, and 208Pb) of dated sediment cores from two coastal estuaries and two inland lakes chronicle the predominance of industrial lead emissions in Mexico over the past century. These isotopic ratios exhibit a shift in composition from the turn of the previous century (1900) that corresponds with measurable increases (from 2- to 10-fold) in lead concentrations in the cores above their baseline values (3-22 microg/g)--both changes are consistent with the development of Mexican lead production for export and the manufacture of tetraethyl lead additives for Mexican gasolines. While subsequent changes in lead concentrations in the cores correspond with calculated emissions from the combustion of leaded gasoline in Mexico, isotopic compositions of the cores remain relatively constant throughout most of the 1900s (e.g., 206Pb/207Pb = 1.200 +/- 0.003; 208Pb/207Pb = 2.463 +/- 0.004). That isotopic constancy is attributed to the widespread pollution from lead production in Mexico and the dispersion of some of that lead used as an additive in Mexican gasolines.

  13. 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, ...

  14. 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 ...

  15. 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 ...

  16. 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 ...

  17. 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....

  18. 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 ...

  19. 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 ...

  20. 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. (© ...

  1. 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.

  2. 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...

  3. Who Leads China's Leading Universities?

    Science.gov (United States)

    Huang, Futao

    2017-01-01

    This study attempts to identify the major characteristics of two different groups of institutional leaders in China's leading universities. The study begins with a review of relevant literature and theory. Then, there is a brief introduction to the selection of party secretaries, deputy secretaries, presidents and vice presidents in leading…

  4. Removal of lead(II) ions from aqueous solutions using cashew nut ...

    African Journals Online (AJOL)

    CNSL) or one of its phenolic constituents, cardanol, as templates. The procedure involved formation of a CNSL or cardanol emulsion in a water-ethanol system into which (3-mercaptopropyl)-trimethoxysilane and tetraethyl orthosilicate were ...

  5. A comparative study of manganese and lead levels in human umbilical cords and maternal blood from two urban centers exposed to different gasoline additives

    Energy Technology Data Exchange (ETDEWEB)

    Audrey, Smargiassi; Donna, Mergler; Genevieve, St-Amour [CINBIOSE, University of Quebec in Montreal, C.P. 8888, succ. Centre Ville, H3C 3P8 Montreal Quebec (Canada); Takser, Larissa; Georgette, Hellier; Guy, Huel [INSERM, Research in Epidemiology and Biostatistics, Villejuif (France); Andre, Masse; Martin, Sergerie [CHUM, St. Luc Hospital, Montreal, Quebec (Canada); Philippe, Blot [Department of Obstetrics, Robert Debre Hospital, Paris (France)

    2002-05-06

    Manganese (Mn) and lead (Pb) are two neurotoxic chemicals and experimental evidence suggests that they can cross the placental barrier. Tetraethyl lead was still in use as an antiknock agent in Paris during the sampling period of the study, while it has been replaced by methylcyclopentadienyl manganese tricarbonyl (MMT) in Canada since 1977. By 1990, MMT was in 100% of gasoline in Canada. In a study of 160 pairs of mothers-neonates in Montreal and 206 pairs in Paris, we compared levels of Mn and Pb in the umbilical cord and in maternal blood. Neonates and mothers had significantly higher Pb levels in Paris where lead additives were still used in gasoline. Geometric mean maternal blood Pb levels were 5.4 {mu}g/dl compared to 2.1 {mu}g/dl in Montreal and cord blood Pb levels were 3.2 {mu}g/dl in Parisian mothers compared to 1.7 {mu}g/dl in Montreal. The prevalence of Paris Pb values superior to the 95th percentile of the Montreal distribution was highly elevated in all media studied. The prevalence of high Mn levels in umbilical cord blood was also significantly higher in Montreal. Surveillance programs are important to limit Pb overexposure and associated neurological effects in neonates where tetraethyl Pb is still in use as a gasoline additive. Since Mn is an essential element and dietary Mn intake may differ between Montreal and Paris, the difference observed with regard to high Mn values between Montreal and Paris cannot, at this time, be attributed to MMT in Montreal's gasoline. Further studies are needed to infer an association between Mn emissions from MMT and prenatal exposure to Mn.

  6. ECG monitoring leads and special leads.

    Science.gov (United States)

    Francis, Johnson

    ECG monitoring is common place in the hospital and even pre-hospital setting. The need for different types of lead systems in different settings has been emphasised. Simple three electrode bipolar recording is ubiquitous for monitoring. This can be used to record modified bipolar chest leads as well. Using five leads gives the option of getting a chest lead in addition to bipolar limb leads, enhancing detection of ischemia during procedures. Lead stability is important when the movement of the subject is maximum as in exercise testing. Mason-Likar modification with limb leads shifted to the torso is popular for exercise testing, though the diagnostic value of the ECG is altered. Lund system with leads on proximal part of limbs have both stability and fair diagnostic value. EASI lead system permits derivation of 12 leads from just five electrodes. Lewis lead and the newly devised modified limb lead system are useful in enhancing detection of atrial activity. Fontaine lead has been designed to improve visualization of Epsilon wave in arrhythmogenic right ventricular dysplasia. Copyright © 2016 Indian Heart Rhythm Society. Production and hosting by Elsevier B.V. All rights reserved.

  7. Learn about Lead

    Science.gov (United States)

    ... Protection Agency Search Search Lead Contact Us Share Learn about Lead General Lead Information Read more about ... water, soil, consumer products, food, and occupational settings. Learn more about sources of lead exposure: At home ...

  8. Lead Poisoning Prevention Tips

    Science.gov (United States)

    ... or removed safely. How are children exposed to lead? Lead-based paint and lead contaminated dust are ... What can be done to prevent exposure to lead? It is important to determine the construction year ...

  9. Lead levels - blood

    Science.gov (United States)

    Blood lead levels ... is used to screen people at risk for lead poisoning. This may include industrial workers and children ... also used to measure how well treatment for lead poisoning is working. Lead is common in the ...

  10. Geogenic lead isotope signatures from meat products in Great Britain: Potential for use in food authentication and supply chain traceability

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Jane A.; Pashley, Vanessa [NIGL, BGS, Keyworth, NG12 5GG (United Kingdom); Richards, Gemma J. [School of Veterinary Science, University of Bristol, Bristol BS40 5DU (United Kingdom); Brereton, Nicola [The Food and Environment Research Agency, Sand Hutton, York YO41 1LZ (United Kingdom); Knowles, Toby G. [School of Veterinary Science, University of Bristol, Bristol BS40 5DU (United Kingdom)

    2015-12-15

    This paper presents lead (Pb) isotope data from samples of farm livestock raised in three areas of Britain that have elevated natural Pb levels: Central Wales, the Mendips and the Derbyshire Peak District. This study highlights three important observations; that the Pb found in modern British meat from these three areas is geogenic and shows no clear evidence of modern tetraethyl anthropogenic Pb contribution; that the generally excellent match between the biological samples and the ore field data, particularly for the Mendip and Welsh data, suggests that this technique might be used to provenance biological products to specific ore sites, under favourable conditions; and that modern systems reflect the same process of biosphere averaging that is analogous to cultural focusing in human archaeological studies that is the process of biological averaging leading to an homogenised isotope signature with increasing Pb concentration. - Highlights: • Lead (Pb) isotopes measured in modern British meat were geogenic in origin. • The match indicates that this technique may be used to provenance biological products. • There was no evidence for a contribution from modern anthropogenic Pb sources.

  11. 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…

  12. Lead (Pb) Air Pollution

    Science.gov (United States)

    ... Environmental Protection Agency Search Search Lead (Pb) Air Pollution Contact Us Share As a result of EPA's ... protect aquatic and terrestrial ecosystems. Lead (Pb) Air Pollution Basic Information How does lead get in the ...

  13. Cryogenic current leads

    Energy Technology Data Exchange (ETDEWEB)

    Zizek, F.

    1982-01-01

    Theoretical, technical and design questions are examined of cryogenic current leads for SP of magnetic systems. Simplified mathematical models are presented for the current leads. To illustrate modeling, the calculation is made of the real current leads for 500 A and three variants of current leads for 1500 A for the enterprise ''Shkoda.''

  14. Lead content of foodstuffs.

    Science.gov (United States)

    Mitchell, D G; Aldous, K M

    1974-05-01

    The lead content of a number of foodstuffs, particularly baby fruit juices and milk, is reported. Samples were analyzed in quadruplicate by using an automated Delves cup atomic absorption procedure. A large proportion of the products examined contained significant amounts of lead. Of 256 metal can examined, the contents of 62% contained a lead level of 100 mug/l. or more, 37% contained 200 mug/l. or more and 12% contained 400 mug/l. lead or more. Of products in glass and aluminum containers, only 1% had lead levels in excess of 200 mug/l. Lead levels of contents also correlate with the seam length/volume ratio of the leaded seam can. A survey of bulk milk showed a mean lead level of 40 mug/l. for 270 samples; for canned evaporated milk the mean level was 202 mug/l. These data indicate a potential health hazard.

  15. Lead and tap water

    Science.gov (United States)

    Water contaminated with lead ... The Environmental Protection Agency (EPA) monitors drinking water in the United States. It requires water suppliers to produce annual water quality reports. These reports include information about lead amounts, and they ...

  16. NA49: lead-lead collision

    CERN Multimedia

    1996-01-01

    This is an image of an actual lead ion collision taken from tracking detectors on the NA49 experiment, part of the heavy ion project at CERN. These collisions produce a very complicated array of hadrons as the heavy ions break up. It is hoped that one of these collisions will eventually create a new state of matter known as quark-gluon plasma.

  17. Lead Poisoning (For Parents)

    Science.gov (United States)

    ... Needs a Kidney Transplant Vision Facts and Myths Lead Poisoning KidsHealth > For Parents > Lead Poisoning Print A ... Family en español La intoxicación por plomo About Lead Poisoning If you have young kids, it's important ...

  18. Lead Poisoning in Childhood.

    Science.gov (United States)

    Pueschel, Siegfried M., Ed.; Linakis, James G., Ed.; Anderson, Angela C., Ed.

    The magnitude of childhood lead poisoning has been inexplicably neglected by modern medicine and by legislators. However, since the 1970s, increased attention has been focused on lead poisoning, and advances have been made in several areas, including understanding of the neurodevelopmental and behavioral ramifications of lead poisoning, and…

  19. Lead poisoning: An overview

    Science.gov (United States)

    Gendel, Neil

    1993-01-01

    A problem that should be of great concern to all of us is the lead poisoning of children. First, I would like to present a short overview concerning the reasons everyone should care about lead poisoning, then discuss the history of lead poisoning, what is happening today across the country, and the future.

  20. Lead Poisoning in Children.

    Science.gov (United States)

    Drummond, A. H., Jr.

    1981-01-01

    Early symptoms of lead poisoning in children are often overlooked. Lead poisoning has its greatest effects on the brain and nervous system. The obvious long-term solution to the lead poisoning problem is removal of harmful forms of the metal from the environment. (JN)

  1. Lead encephalopathy in adults

    Directory of Open Access Journals (Sweden)

    Janapareddy Vijaya Bhaskara Rao

    2014-01-01

    Full Text Available Lead poisoning is a common occupational health hazard in developing countries. We report the varied clinical presentation, diagnostic and management issues in two adult patients with lead encephalopathy. Both patients worked in a battery manufacturing unit. Both patients presented with seizures and one patient also complained of abdominal colic and vomiting. Both were anemic and a lead line was present. Blood lead level in both the patients was greater than 25 µg/dl. Magnetic resonance imaging of brain revealed bilateral symmetric involvement of the thalamus, lentiform nucleus in both patients and also the external capsules, sub-cortical white matter in one patient. All these changes, seen as hyperintensities in T2-weighted images suggested demyelination. They were advised avoidance of further exposure to lead and were treated with anti-epileptics; one patient also received D-penicillamine. They improved well on follow-up. Lead encephalopathy is an uncommon but important manifestation of lead toxicity in adults.

  2. Lead in the environment

    Science.gov (United States)

    Pattee, Oliver H.; Pain, Deborah J.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

    2003-01-01

    Anthropogenic uses of lead have probably altered its availability and environmental distribution more than any other toxic element. Consequently, lead concentrations in many living organisms may be approaching thresholds of toxicity for the adverse effects of lead. Such thresholds are difficult to define, as they vary with the chemical and physical form of lead, exposure regime, other elements present and also vary both within and between species. The technological capability to accurately quantify low lead concentrations has increased over the last decade, and physiological and behavioral effects have been measured in wildlife with tissue lead concentrations below those previously considered safe for humans.s.236 Consequently. lead criteria for the protection of wildlife and human health are frequently under review, and 'thresholds' of lead toxicity are being reconsidered. Proposed lead criteria for the protection of natural resources have been reviewed by Eisler. Uptake of lead by plants is limited by its generally low availability in soils and sediments, and toxicity may be limited by storage mechanisms and its apparently limited translocation within most plants. Lead does not generally accumulate within the foliar parts of plants, which limits its transfer to higher trophic levels. Although lead may concentrate in plant and animal tissues, no evidence of biomagnification exists. Acid deposition onto surface waters and soils with low buffering capacity may influence the availability of lead for uptake by plants and animals, and this may merit investigation at susceptible sites. The biological significance of chronic low-level lead exposure to wildlife is sometimes difficult to quantify. Animals living in urban environments or near point sources of lead emission are inevitably subject to greater exposure to lead and enhanced risk of lead poisoning. Increasingly strict controls on lead emissions in many countries have reduced exposure to lead from some sources

  3. ALICE: Simulated lead-lead collision

    CERN Document Server

    2003-01-01

    This track is an example of simulated data modelled for the ALICE detector on the Large Hadron Collider (LHC) at CERN, which will begin taking data in 2008. ALICE will focus on the study of collisions between nuclei of lead, a heavy element that produces many different particles when collided. It is hoped that these collisions will produce a new state of matter known as the quark-gluon plasma, which existed billionths of a second after the Big Bang.

  4. Removal of lead(II ions from aqueous solutions using cashew nut shell liquid-templated thiol-silica materials

    Directory of Open Access Journals (Sweden)

    J. E. G. Mdoe

    2014-09-01

    Full Text Available A range of thiol-silica composites were prepared using cashew nut shell liquid (CNSL or one of its phenolic constituents, cardanol, as templates. The procedure involved formation of a CNSL or cardanol emulsion in a water-ethanol system into which (3-mercaptopropyl-trimethoxysilane and tetraethyl orthosilicate were simultaneously added at various ratios. The reaction mixture was aged at room temperature for 18 h followed by a Soxhlet extraction of the template and drying. The materials were characterized by diffuse reflectance Fourier transform infrared, nitrogen physisorption, scanning electron microscopy and acid titration. Results indicated that indeed the thiol-silica composites were successfully prepared, with thiol group loadings ranging from 1.6-2.5 mmol/g. The materials were tested for lead(II adsorption, and results showed that they had maximum adsorption capacities up to 66.7 mg/g, depending on the thiol group loading and type of template used in preparing the adsorbent. DOI: http://dx.doi.org/10.4314/bcse.v28i3.5

  5. Organic Lead Toxicology

    Directory of Open Access Journals (Sweden)

    Jiří Patočka

    2008-01-01

    Full Text Available Lead is one of the oldest known and most widely studied occupational and environmental poison. Despite intensive study, there is still debate about the toxic effects of lead, both from low-level exposure in the general population owing to environmental pollution and historic use of lead in paint and plumbing and from exposure in the occupational setting. Significant position have organic lead compounds used more than 60 years as antiknock additives in gasoline. Chemical and toxicological characteristics of main tetraalkyl leads used as gasoline additives are discussed in this article. The majority of industries historically associated with high lead exposure have made dramatic advances in their control of occupational exposure. However, cases of unacceptably high exposure and even of frank lead poisoning are still seen, predominantly in the demolition and tank cleaning industries. Nevertheless, in most industries blood lead levels have declined below levels at which signs or symptoms are seen and the current focus of attention is on the subclinical effects of exposure. The significance of some of these effects for the overt health of the workers is often the subject of debate. Inevitably there is pressure to reduce lead exposure in the general population and in working environments, because current studies show that no level of lead exposure appears to be a ‘safe’ and even the current ‘low’ levels of exposure, especially in children, are associated with neurodevelopmental deficits.

  6. Lead-Free Piezoelectrics

    CERN Document Server

    Nahm, Sahn

    2012-01-01

    Ecological restrictions in many parts of the world are demanding the elimination of Pb from all consumer items. At this moment in the piezoelectric ceramics industry, there is no issue of more importance than the transition to lead-free materials. The goal of Lead-Free Piezoelectrics is to provide a comprehensive overview of the fundamentals and developments in the field of lead-free materials and products to leading researchers in the world. The text presents chapters on demonstrated applications of the lead-free materials, which will allow readers to conceptualize the present possibilities and will be useful for both students and professionals conducting research on ferroelectrics, piezoelectrics, smart materials, lead-free materials, and a variety of applications including sensors, actuators, ultrasonic transducers and energy harvesters.

  7. EFFECT OF LEAD ACETATE

    African Journals Online (AJOL)

    MICROSOFT

    The project was conducted to evaluate the effect of lead administered as lead acetate at different dosage levels via drinking water in broiler chicks. Thirty-five healthy chicks were divided into seven groups (five chicks each) and one group was kept as un-medicated control. Groups A, B, C, D, E and F were medicated with ...

  8. Leading Acquisition Reform

    Science.gov (United States)

    2011-03-22

    Army and Undersecretary of Defense for Acquisition, for a reduction of the Excalibur and Accelerated Precision Mortar initiative rounds.25...Can’t Dance? Leading a Great Enterprise Through Dramatic Change, (New York: HarperCollins Publishers, 2003), 235. 13 John P. Kotter , Leading Change

  9. Developmental immunotoxicology of lead.

    Science.gov (United States)

    Dietert, Rodney R; Lee, Ji-Eun; Hussain, Irshad; Piepenbrink, Michael

    2004-07-15

    The heavy metal, lead, is a known developmental immunotoxicant that has been shown to produce immune alterations in humans as well as other species. Unlike many compounds that exert adverse immune effects, lead exposure at low to moderate levels does not produce widespread loss of immune cells. In contrast, changes resulting from lead exposure are subtle at the immune cell population level but, nevertheless, can be functionally dramatic. A hallmark of lead-induced immunotoxicity is a pronounced shift in the balance in T helper cell function toward T helper 2 responses at the expense of T helper 1 functions. This bias alters the nature and range of immune responses that can be produced thereby influencing host susceptibility to various diseases. Immunotoxic responses to lead appear to differ across life stages not only quantitatively with regard to dose response, but also qualitatively in terms of the spectrum of immune alterations. Experimental studies in several lab animal species suggest the latter stages of gestation are a period of considerable sensitivity for lead-induced immunotoxicity. This review describes the basic characteristics of lead-induced immunotoxicity emphasizing experimental animal results. It also provides a framework for the consideration of toxicant exposure effects across life stages. The existence of and probable basis for developmental windows of immune hyper-susceptibility are presented. Finally, the potential for lead to serve as a perinatal risk factor for childhood asthma as well as other diseases is considered.

  10. Lead - nutritional considerations

    Science.gov (United States)

    ... lead soldered cans goes into effect. If imported wine containers have a lead foil wrapper, wipe the rim and neck of the bottle with a towel moistened with lemon juice, vinegar, or wine before using. DO NOT store wine, spirits, or ...

  11. Lead toxicity: Current concerns

    Energy Technology Data Exchange (ETDEWEB)

    Goyer, R.A. (Univ. of Western Ontario, London (Canada))

    1993-04-01

    Over the 20-year period since the first issue of Environmental Health Perspectives was published, there has been considerable progress in the understanding of the potential toxicity of exposure to lead. Many of these advances have been reviewed in published symposia, conferences, and review papers in EHP. This brief review identifies major advances as well as a number of current concerns that present opportunities for prevention and intervention strategies. The major scientific advance has been the demonstration that blood lead (PbB) levels of 10-15 micrograms/dL in newborn and very young infants result in cognitive and behavioral deficits. Further support for this observation is being obtained by prospective or longitudinal studies presently in progress. The mechanism(s) for the central nervous system effects of lead is unclear but involve lead interactions within calcium-mediated intracellular messenger systems and neurotransmission. Effects of low-level lead exposure on blood pressure, particularly in adult men, may be related to the effect of lead on calcium-mediated control of vascular smooth muscle contraction and on the renin-angiotensin system. Reproductive effects of lead have long been suspected, but low-level effects have not been well studied. Whether lead is a carcinogen or its association with renal adenocarcinoma is a consequence of cystic nephropathy is uncertain. Major risk factors for lead toxicity in children in the United States include nutrition, particularly deficiencies of essential metals, calcium, iron, and zinc, and housing and socioeconomic status. A goal for the year 2000 is to reduce prevalence of blood lead levels exceeding 15 micrograms/dL. 97 refs.

  12. Synthetic of Allophane-Like and Adsorption for Lead (Pb) Heavy Metals

    Science.gov (United States)

    Pranoto; Purnawan, C.; Widyasari, A. D.

    2017-07-01

    A synthesis allophone-like had been done from aluminum nitrate nonahidrat (Al (NO3)3.9H2O) and tetraethyl orthosilicate (TEOS). This study aims to determine synthesis of allophane-like based on variations in the ratio of Al/Si is applied as an adsorbent for the lead (Pb) metal. The study was conducted with ratio variation Al/Si 0.5; 0.75; 1; 1.25 and 1.5 from solution volume nonahidrat (Al (NO3)3.9H2O) and TEOS at pH 3-4 calcined at temperature of 400°C. The adsorption type is determined by the adsorption isotherm. The results of the research shows that allophane-like can be synthetized from a solution of nonahidrat (Al (NO3)3.9H2O) and TEOS with a variation of the ratio of Al/Si 0.5; 0.75; 1; 1.25 and 1.5. Allophane-like has function groups of -OH group; spanning asymmetrical form of O-Si-O/O-Al-O; Si-O/Al-O bending vibration and relatively weak absorption which strengthen their OH group. The results of allophane-like adsorption capacity of 1.61 mg/g in the ratio Al/Si of 1.5 at pH 4 with a contact time of 30 minutes with a percentage of 80.77% adsorption. The adsorptions of Pb heavy metals with allophane-like tend to follow the type of adsorption isotherms of Freundlich or physics.

  13. Lead User Innovation

    DEFF Research Database (Denmark)

    Brem, Alexander; Larsen, Henry

    2015-01-01

    User innovation and especially the integration of lead users is a key topic in the innovation management literature of recent years. This paper contributes by providing a rare perspective into what easily could be seen as innovation failure, shown from two perspectives. We show how a lack of shared...... imagination hampers participation and kills innovation between interdependent stakeholders at the threshold between invention and innovation in practice. We present a first case in the fun-sport industry where an external lead user and diverse firm representatives in different functions fail to create......, deliver and capture the value of an innovatively new device together. From the perspective of the lead user, we show antecedents and effects of social interaction between organizational actors and the lead user on the development of social capital, especially trust and shared imagination. The second case...

  14. Magnesium Diboride Current Leads

    Science.gov (United States)

    Panek, John

    2010-01-01

    A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Dis covered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these leads is to provide 2 A of electricity to motors located in a 1.3 K environment. The providing environment is a relatively warm 17 K. Requirements for these leads are to survive temperature fluctuations in the 5 K and 11 K heat sinks, and not conduct excessive heat into the 1.3 K environment. Test data showed that each lead in the assembly could conduct 5 A at 4 K, which, when scaled to 17 K, still provided more than the required 2 A. The lead assembly consists of 12 steelclad MgB2 wires, a tensioned Kevlar support, a thermal heat sink interface at 4 K, and base plates. The wires are soldered to heavy copper leads at the 17 K end, and to thin copper-clad NbTi leads at the 1.3 K end. The leads were designed, fabricated, and tested at the Forschungszentrum Karlsruhe - Institut foer Technische Physik before inclusion in Goddard's XRS (X-Ray Spectrometer) instrument onboard the Astro-E2 spacecraft. A key factor is that MgB2 remains superconducting up to 30 K, which means that it does not introduce joule heating as a resistive wire would. Because the required temperature ranges are 1.3-17 K, this provides a large margin of safety. Previous designs lost superconductivity at around 8 K. The disadvantage to MgB2 is that it is a brittle ceramic, and making thin wires from it is challenging. The solution was to encase the leads in thin steel tubes for strength. Previous designs were so brittle as to risk instrument survival. MgB2 leads can be used in any cryogenic application where small currents need to be conducted at below 30 K. Because previous designs would superconduct only at up to 8 K, this new design would be ideal for the 8-30 K range.

  15. Lead toxicity in plants

    OpenAIRE

    Sharma, Pallavi; Dubey, Rama Shanker

    2005-01-01

    Contamination of soils by heavy metals is of widespread occurrence as a result of human, agricultural and industrial activities. Among heavy metals, lead is a potential pollutant that readily accumulates in soils and sediments. Although lead is not an essential element for plants, it gets easily absorbed and accumulated in different plant parts. Uptake of Pb in plants is regulated by pH, particle size and cation exchange capacity of the soils as well as by root exudation and other physico-che...

  16. Leading through Conflict

    Science.gov (United States)

    Gerzon, Mark

    2006-01-01

    This article talks about leading significant learning opportunities through conflict of ideas in a school system. Catalyzing school change can turn emotional differences of opinion into learning opportunities. Leaders who want to deal effectively with these challenging, often tense situations need to be more than good managers. They need to be…

  17. Turning lead into gold

    DEFF Research Database (Denmark)

    Jensen, Steffen Moltrup Ernø

    For years the field of entrepreneurship has been blinded by the alchemical promise of turning lead into gold, of finding the ones most likely to become the next Branson, Zuckerberg or Gates. The promise has been created in the midst of political and scientific agendas where certain individuals...

  18. Relational Perspectives on Leading

    DEFF Research Database (Denmark)

    Relational Perspectives on Leading discusses leadership from a relational and social constructionism perspective as practiced on an everyday basis between people. The book pursues a fast growing, practice-based approach - particularly within the Anglo-Saxon parts of the world - to organization...

  19. Relational Perspectives on Leading

    DEFF Research Database (Denmark)

    Larsen, Mette Vinther; Rasmussen, Jørgen Gulddahl

    2015-01-01

    Relational Perspectives on Leading discusses leadership from a relational and social constructionism perspective as practiced on an everyday basis between people. The book pursues a fast growing, practice-based approach - particularly within the Anglo-Saxon parts of the world - to organization...

  20. Managing, Leading, and Bossing

    Science.gov (United States)

    2011-08-01

    Defense AT&L: July–August 2011 76 Managing , Leading, and Bossing Stan Emelander Boss Manager Leader Emelander is a project manager in the Army’s...and management . He is level II certified in program management and level I in systems engineering. Leaders fascinate us. From the smallest shop to...me about your boss” will work. Another great question is, “What’s the difference between a leader and a manager ?” Early in my career, I thought there

  1. Lead tungstate scintillation material

    CERN Document Server

    Annenkov, A N; Lecoq, P

    2002-01-01

    In this paper we summarize the results of a research programme on lead-tungstate (PWO) crystals performed by the CMS Collaboration at CERN, as well as by other groups who promoted the progress of the PWO scintillation crystal technology. Crystal properties, mass production technology, scintillation mechanism, origin of colouring, defects in crystal and radiation induced phenomena, light yield improvement and results of beam tests are described. (96 refs).

  2. lead glass brick

    CERN Multimedia

    When you look through the glass at a picture behind, the picture appears raised up because light is slowed down in the dense glass. It is this density (4.06 gcm-3) that makes lead glass attractive to physicists. The refractive index of the glass is 1.708 at 400nm (violet light), meaning that light travels in the glass at about 58% its normal speed. At CERN, the OPAL detector uses some 12000 blocks of glass like this to measure particle energies.

  3. Leading change: 2--planning.

    Science.gov (United States)

    Kerridge, Joanna

    National initiatives have outlined the importance of involving frontline staff in service improvement, and the ability to influence and manage change has been identified as an essential skill for delivering new models of care. Nurses often have to take the lead in managing change in clinical practice. The second in a three-part series is designed to help nurses at all levels develop the knowledge and skills to function as change agents within their organisations. This article focuses on planning the change and dealing with resistance.

  4. Liver and Renal Function Tests in Artisans Occupationally Exposed to Lead in Mechanic Village in Nnewi, Nigeria

    Directory of Open Access Journals (Sweden)

    S. C. Meludu

    2004-02-01

    Full Text Available Additives in petroleum solvents have been reported to have adverse health implications. An evaluation study on some toxicological effects of occupational exposure to petroleum products (especially petrol which contains tetraethyl lead amongst twenty five occupationally exposed artisans and twenty five graduate students of College of Health Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria as controls, was carried out using the following biochemical markers: electrolytes, urea, uric acid, inorganic phosphorus, creatinine, zinc and blood lead, as well as the activities of alanine and aspartate aminotransferases, and alkaline phosphatase. The results showed that occupational exposure of human subjects to lead in petrol increases the concentrations of uric acid (357 ± 123μ mol/L and phosphate (1.5 ± 0.5m mol/L in exposed subjects compared with unexposed subjects (uric acid 228 ± 105μ mol/L, phosphate 1.2 ± 0.41m mol/L; p < 0.01 in both cases. Significantly lower activities were observed for alkaline phosphatase (66 ± 18.9 iu/L. The activities of alanine aminotransferase (11.4 ± 4.0 iu/L and aspartate aminotransferase (15.8 ± 4.4 iu/L in occupationally exposed artisans were higher compared with unexposed subjects (alkaline phosphatase = 78 ± 22.4 iu/L alanine aminotranferase = 6.8 ± 2.7 iu/L, aspartate aminotranferase = 9.6 ± 3.5i u/L; p < 0.01 in all cases. Occupational exposure of human subjects to lead significantly increased blood lead (59.6 ± 15.9 μg/dL and decreased plasma zinc (71.3 ± 14.4 μg/L in exposed compared with unexposed subjects (blood lead = 35 ± 7 μg/dL, zinc = 108.4 ± 16.9 μg/dL; p < 0.01. The results indicate that occupational exposure to lead in petrol may compromise liver and renal function.

  5. Lead and lead-based alloys as waste matrix materials

    Energy Technology Data Exchange (ETDEWEB)

    Arustamov, A.E.; Ojovan, M.I.; Kachalov, M.B.

    1999-07-01

    Metals and alloys with relatively low melting temperatures such as lead and lead-based alloys are considered in Russia as prospective matrices for encapsulation of spent nuclear fuel in containers in preparation for final disposal in underground repositories. Now lead and lead-based alloys are being used for conditioning spent sealed radioactive sources at radioactive waste disposal facilities.

  6. HAIR LEAD CONCENTRATION IN NAKHLAK LEAD MINERS VERSUS CONTROL GROUP

    Directory of Open Access Journals (Sweden)

    N IZADI

    2002-03-01

    Full Text Available Introduction. Lead poisoning is a major problem in environmental health. Exposure can occur via air, soil, food and water. Occupational exposure is the most common source of lead poisoning in adults. Lead miners are exposed to an additional source of poisoning in long term. Hair analysis may be used to evaluate chronic lead toxicity. This study compare the hair lead concentration in Nakhlak lead miners and Mohammadieh people who live 130 km far from the lead mine. Methods. Hair samples from 24 Nakhlak lead miners and 26 adult men of Mohammadieh village were gathered, washed by detergent and distilled water and dissolved by wet digestion. Lead concentrations of the samples were measured by flame atomic absorption spectroscopy. Results. There was a significant difference between hair lead concentration of Nakhlak lead miners and Mohammadieh people (P < 0.001. The mean of lead concentrations were 52.43±27.7 µg/g (mean ± SD and 17.32±3.43 µg/g hair of the lead mine workers and the Mohammadieh people, respectively. There was also a significant regression between the number of exposure years and the lead concentration of hair in Nakhlak lead miners (P < 0.001, r=0.8. Discussion. Presence of lead compounds in work environment especially in the air may be an important factor for the difference between hair lead concentration of Nakhlak lead miners and Mohammadieh people. However, the hair lead concentration in Mohammadieh people is also reasonably high. It means that these people are also exposed to lead through the other sources e.g. food, soil, water and air.

  7. Human lead metabolism: Chronic exposure, bone lead and physiological models

    Science.gov (United States)

    Fleming, David Eric Berkeley

    Exposure to lead is associated with a variety of detrimental health effects. After ingestion or inhalation, lead may be taken up from the bloodstream and retained by bone tissue. X-ray fluorescence was used to make in vivo measurements of bone lead concentration at the tibia and calcaneus for 367 active and 14 retired lead smelter workers. Blood lead levels following a labour disruption were used in conjunction with bone lead readings to examine the endogenous release of lead from bone. Relations between bone lead and a cumulative blood lead index differed depending on time of hiring. This suggests that the transfer of lead from blood to bone has changed over time, possibly as a result of varying exposure conditions. A common polymorphism in the δ-aminolevulinate dehydratase (ALAD) enzyme may influence the distribution of lead in humans. Blood lead levels were higher for smelter workers expressing the more rare ALAD2 allele. Bone lead concentrations, however, were not significantly different. This implies that a smaller proportion of lead in blood is distributed to tissue for individuals expressing the ALAD2 allele. The O'Flaherty physiological model of lead metabolism was modified slightly and tested with input from the personal exposure histories of smelter workers. The model results were consistent with observation in tern of endogenous exposure to lead and accumulation of lead in cortical bone. Modelling the calcaneus as a trabecular bone site did not reproduce observed trends. variations in lead metabolism between different trabecular sites may therefore be significant. The model does not incorporate a genetic component, and its output did not reflect observed differences in this respect. This result provides further support for the influence of the ALAD polymorphism on lead metabolism. Experimental trials with a digital spectrometer revealed superior energy resolution and count throughput relative to the conventional X-ray fluorescence system. The associated

  8. Drowning: a leading killer!

    Directory of Open Access Journals (Sweden)

    Nuno Domingos Garrido

    2016-10-01

    Full Text Available Drowning kills at least 372,000 people worldwide every year and is the 3rd leading cause of unintentional death, accounting for 7% of all deaths stemming from accidents (WHO, 2014. Conceptually, “drowning” is a complex and multi-faceted phenomenon, characterized as a chain of events (Bierens, 2006. Drowning is defined as the process of experiencing respiratory impairment from immersion or submersion in liquid. Research on drowning as a phenomenon presents several difficulties - most of all, that global data concerning the number of occurrences are not accurate. Nevertheless, detailed analysis of the registered incidents allows the identification of risk factors of drowning. An in-depth analysis of the risk factors is the basis for the creation of targeted and effective strategies to prevent drowning. Due to variability of situations which could lead to a drowning episode, experts suggest the adoption of a multi-layer prevention model, rather than opting for isolated measures, since no single measure can prevent all deaths and injuries caused by submersion. Among the preventive measures we would like to emphasize instruction in swimming and water safety. So, what does "knowing how to swim" really mean? Some authors define mastery of this competence as swimming a given distance, while others put the emphasis on how this/any given distance is swum (Stallman, Junge, & Blixt, 2008. It has long been realized that there is no contradiction between learning those competencies which make a person less susceptible to drowning and those competencies which prepare the path towards higher levels of performance and competition. Aquatic movement researchers and practitioners and drowning prevention researchers and practitioners, share in the responsibility for drowning prevention though they are often unaware of it. The question “What should be taught to children?” is too infrequently asked. There remains great variation in what is taught and programs

  9. Leading Your Leaders

    Science.gov (United States)

    Hale, Wayne N.

    2008-01-01

    life is good. More often when an unbelievably difficult test fails, we are left with a very long discussion of why and what was wrong in the design or execution of the test. Make sure that the test is well defined. Even then, it is important to explain to your leaders what inherent accuracy (or error) the test conditions or equipment have and what the assumptions or initial conditions were for the test. Test results without a good understanding of the test's accuracy or the pedigree of the test assumptions are worth very little. Finally, there is flight test data. Always limited, never at the edge of the envelope, it still shows how the real hardware works in a combined environment. Flight experience is dangerous because it typically doesn't show how close to the edge of the cliff the equipment is operating, but it does demonstrate how the hardware really works. A flight test is the ultimate test, again taken with the knowledge that it is probably not the extreme but something more like the middle of the environmental and systems performance. Good understanding of a problem and its solution always relies on a combination of all these methods. Be sure to lead your leaders by using all the tools you have at your disposal. At the end of the day, decisions in space flight always come down to a risk trade. Our business is not remotely safe, not in the sense that the public, the media, or our legislators use the term. Everything we do has a risk, cost, schedule, or performance trade-off. For your leaders to make an appropriate decision, you need to educate them, lead them, talk with them, and engage them in the discussion until full understanding takes place. It's your job. *

  10. Leading clever people.

    Science.gov (United States)

    Goffee, Rob; Jones, Gareth

    2007-03-01

    In an economy driven by ideas and intellectual know-how, top executives recognize the importance of employing smart, highly creative people. But if clever people have one defining characteristic, it's that they do not want to be led. So what is a leader to do? The authors conducted more than 100 interviews with leaders and their clever people at major organizations such as PricewaterhouseCoopers, Cisco Systems, Novartis, the BBC, and Roche. What they learned is that the psychological relationships effective leaders have with their clever people are very different from the ones they have with traditional followers. Those relationships can be shaped by seven characteristics that clever people share: They know their worth--and they know you have to employ them if you want their tacit skills. They are organizationally savvy and will seek the company context in which their interests are most generously funded. They ignore corporate hierarchy; although intellectual status is important to them, you can't lure them with promotions. They expect instant access to top management, and if they don't get it, they may think the organization doesn't take their work seriously. They are plugged into highly developed knowledge networks, which both increases their value and makes them more of a flight risk. They have a low boredom threshold, so you have to keep them challenged and committed. They won't thank you--even when you're leading them well. The trick is to act like a benevolent guardian: to grant them the respect and recognition they demand, protect them from organizational rules and politics, and give them room to pursue private efforts and even to fail. The payoff will be a flourishing crop of creative minds that will enrich your whole organization.

  11. Safety and Health Topics: Lead

    Science.gov (United States)

    ... gray, heavy metal that occurs naturally in the Earth’s crust. Lead was one of the first metals ... even at very low blood lead levels. Pregnant women or those who might become pregnant must avoid ...

  12. Lead Exposure Hazard Management Guide

    Science.gov (United States)

    1993-12-01

    effects of lead on humans beings have been known for many years. Acute overexposure to lead can kill in a matter of days. Chronic overexposure to lead in...8217--: -7 Thserconnsa*Im will help achive one of dh nationial health objectives specified by Healthy Peple 2000, which is to eliminate exposures that

  13. Lead poisoning in an adult: lead mobilization by pregnancy?

    Science.gov (United States)

    Riess, Matthias L; Halm, Josiah K

    2007-08-01

    We report a case of acute lead poisoning in an adult female who had last been exposed to lead 7 years ago. She presented with abdominal pain, knee pain, and neurological symptoms, hypertension, chronic kidney disease, and anemia with basophilic stippling and lead gum lines. Compared to during her recent pregnancy, her lead level had almost tripled in 5 months to 81 mcg/dL. Chelation therapy was initiated and improved the patient's symptoms and lead level significantly. In the absence of any new lead exposure or other reasons for increased bone turnover, this acute lead increase was likely due to skeletal mobilization caused by increased resorption from mineralized tissue during and after her pregnancy. This case report illustrates the seriousness of long-term health effects associated with lead poisoning at a multi-organ level, even years after the initial exposure. Thus, patient care should not be limited to the acute treatment of increased lead levels, but also include prevention of increased mobilization and bone turnover and appropriate patient education. In this context, we review various aspects of lead toxicity, especially during pregnancy and lactation.

  14. 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.

  15. Chronic lead poisoning in horses

    Energy Technology Data Exchange (ETDEWEB)

    Knight, H.D.; Burau, R.G.

    1973-05-01

    Chronic lead poisoning in horses was manifested as anorexia, loss of body weight, muscular weakness, anemia, laryngeal hemiplegia, and, terminally, inhalation pneumonia. Some deaths were sudden and unexplained. The lead content in liver specimens from 10 horses was greater than that considered indicative of lead intoxication; however, the lead content of blood was equivocal. The most conclusive laboratory finding was increased urine lead concentration after chelation therapy. The concentration of lead in a sample of vegetation considered to be representative of what a horse would eat if he was grazing in the area sampled was 325 ppM (oven-dry basis). It was determined that a 450-kg horse grazing grass of this lead content would consume 2.9 Gm of lead daily (6.4 mg/kg of body weight), an amount considered toxic for horses. Leaching lowered the calcium content of the forage but failed to reduce the lead concentration of the plants significantly, thus opening the possibility that winter rains might have influenced the onset of poisoning. Airborne fallout from a nearby lead smelter was proposed as the primary mode of pasture contamination.

  16. Childhood lead poisoning: an overview.

    Science.gov (United States)

    Hon, K L; Fung, C K; Leung, A Kc

    2017-12-01

    Childhood lead poisoning is a major public health concern in many countries. In 2015, the Hong Kong SAR Government and its citizens faced a major public health crisis due to the presence of lead in the drinking water of a number of public housing estates. Fortunately, no child was diagnosed with lead poisoning that required treatment with chelation. Lead is a ubiquitous, naturally occurring material that exists in air, dust, soil, and water. It is also widely present in industrial products including petrol, paints, ceramics, food cans, candies, cosmetics, traditional remedies, batteries, solder, stained glass, crystal vessels, ammunition, ceramic glazes, jewellry, and toys. It can also be found in human milk. There is no safe blood lead level and it may be impossible to completely eliminate lead from any city. Hence routine measurement of blood lead levels is not considered useful. Acute poisoning, especially with encephalopathy, deserves immediate medical treatment in hospital. Chelation therapy is recommended if blood lead level is 45 μg/dL or higher. For blood levels between 20 and 45 μg/dL, treatment is indicated if the child is symptomatic. For blood levels below 20 μg/dL in otherwise asymptomatic children, the principle of treatment is to provide long-term neurodevelopmental follow-up and counselling. In all cases, immediate removal of the source of lead exposure is vital. Even low levels of lead exposure can significantly impair learning, educational attainment, and neurodevelopment.

  17. Effect of Probenecid on Tetraethyl Ammonium (TEA) Transport Across Basolateral Membrane of Rabbit Proximal Tubule

    Science.gov (United States)

    Choi, Tae Lyong; Kim, Yong Keun

    1992-01-01

    The effect of probenecid on the transport of tetraethylammonium (TEA) was investigated in rabbit reanal cortical slices in an attempt to ascertain the interaction of organic anion with the organic cation transport system in proximal tubule. Probenecid reversibly inhibited TEA uptake by cortical slices in a dose-dependent manner over the concentration range of 1 and 5 mM. The efflux of TEA was not affected by the presence of 3 mM probenecid. Kinetic analysis indicated that probenecid decreased Vmax without a significant change in Km. Probenecid inhibited significantly tissue oxgen consumption at concentrations of 3 and 5 mM. However, probenecid did not significantly reduce TEA uptake in brush border and basolateral membrane vesicles prepared from renal cortex even at higher concentration of 10 mM. These results indicate that probenecid reduces TEA uptake in cortical slices by inhibiting the tissue metabolism rather than by the interaction with the organic cation transporter. PMID:1306074

  18. Lead toxicity in battery workers.

    Science.gov (United States)

    Qasim, Saeeda Fouzia; Baloch, Malka

    2014-11-01

    Lead poisoning is a medical condition caused by increased levels of lead in the body. Routes of exposure include contaminated air, water, soil, food and consumer products. Occupational exposure is the main cause of lead poisoning in the adults. Two cases of occupational lead poisoning in adult battery workers are hereby presented. Both male patients had initial non-specific symptoms of intermittent abdominal pain, fatigue and headache for 6 - 8 years. Later on, they developed psychosis, slurred speech, tremors of hands and initially underwent treatment for Parkinsonism and Wilson's disease because of clinical misdiagnosis. They were diagnosed with lead poisoning later and were treated successfully with lead chelator (CaNa2 EDTA).

  19. Taking the Lead : Gender, Social Context and Preference to Lead

    NARCIS (Netherlands)

    Hong, A.P.C.I.; Schaafsma, J.; van der Wijst, P.J.

    Previous research has demonstrated that women tend to emerge as leaders less often than men. In the present study, we examined to what extent women's and men's preference to lead is influenced by social context. It was hypothesized that women have a less strong preference to lead than men in a

  20. Undue Lead Absorption and Lead Poisoning in Children: An Overview.

    Science.gov (United States)

    Lin-Fu, J. S.

    The toxic effects of lead, a useful metal ubiquitous in the human environment, have long been known. The occupational hazards of lead poisoning were well established by the early 19th century, but plumbism in children caused by paint ingestion was not reported until the turn of the century. Even in 1924, the child was said to live in a "lead…

  1. Leading Millennials Motivating And Leading Millennial Service Members

    Science.gov (United States)

    2016-02-20

    AIR WAR COLLEGE AIR UNIVERSITY LEADING MILLENNIALS MOTIVATING AND LEADING MILLENNIAL SERVICE MEMBERS by Joanne MacGregor, LTC...young adults ( Millennials ) serving in the U.S. military. These factors may not be readily apparent to Generation X and Y leaders. This paper argues...motivate, and discipline millennial subordinates while maximizing their talents through active and thoughtful professional development. 5

  2. Strategic Military Leaders - Leading Tomorrow

    Science.gov (United States)

    2008-02-29

    St ra te gy R es ea rc h Pr oj ec t STRATEGIC MILITARY LEADERS –LEADING TOMORROW BY COLONEL NG WAI KIT Singapore Army DISTRIBUTION...Strategic Military Leaders - Leading Tomorrow 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Ng Kit 5d. PROJECT...STRATEGIC MILITARY LEADERS – LEADING TOMORROW by Colonel Ng Wai Kit Singapore Army Dr. Leonard Wong Project

  3. Safe Leads and Lead Changes in Competitive Team Sports

    CERN Document Server

    Clauset, A; Redner, S

    2015-01-01

    We investigate the time evolution of lead changes within individual games of competitive team sports. Exploiting ideas from the theory of random walks, the number of lead changes within a single game follows a Gaussian distribution. We show that the probability that the last lead change and the time of the largest lead size are governed by the same arcsine law, a bimodal distribution that diverges at the start and at the end of the game. We also determine the probability that a given lead is "safe" as a function of its size $L$ and game time $t$. Our predictions generally agree with comprehensive data on more than 1.25 million scoring events in roughly 40,000 games across four professional or semi-professional team sports, and are more accurate than popular heuristics currently used in sports analytics.

  4. Safe leads and lead changes in competitive team sports

    Science.gov (United States)

    Clauset, A.; Kogan, M.; Redner, S.

    2015-06-01

    We investigate the time evolution of lead changes within individual games of competitive team sports. Exploiting ideas from the theory of random walks, the number of lead changes within a single game follows a Gaussian distribution. We show that the probability that the last lead change and the time of the largest lead size are governed by the same arcsine law, a bimodal distribution that diverges at the start and at the end of the game. We also determine the probability that a given lead is "safe" as a function of its size L and game time t . Our predictions generally agree with comprehensive data on more than 1.25 million scoring events in roughly 40 000 games across four professional or semiprofessional team sports, and are more accurate than popular heuristics currently used in sports analytics.

  5. High temperature superconductor current leads

    Science.gov (United States)

    Hull, John R.; Poeppel, Roger B.

    1995-01-01

    An electrical lead having one end for connection to an apparatus in a cryogenic environment and the other end for connection to an apparatus outside the cryogenic environment. The electrical lead includes a high temperature superconductor wire and an electrically conductive material distributed therein, where the conductive material is present at the one end of the lead at a concentration in the range of from 0 to about 3% by volume, and at the other end of the lead at a concentration of less than about 20% by volume. Various embodiments are shown for groups of high temperature superconductor wires and sheaths.

  6. Lead Poisoning in Wild Birds

    Science.gov (United States)

    Lahner, Lesanna L.; Franson, J. Christian

    2009-01-01

    Lead in its various forms has been used for thousands of years, originally in cooking utensils and glazes and more recently in many industrial and commercial applications. However, lead is a potent, potentially deadly toxin that damages many organs in the body and can affect all animals, including humans. By the mid 1990s, lead had been removed from many products in the United States, such as paint and fuel, but it is still commonly used in ammunition for hunting upland game birds, small mammals, and large game animals, as well as in fishing tackle. Wild birds, such as mourning doves, bald eagles, California condors, and loons, can die from the ingestion of one lead shot, bullet fragment, or sinker. According to a recent study on loon mortality, nearly half of adult loons found sick or dead during the breeding season in New England were diagnosed with confirmed or suspected lead poisoning from ingestion of lead fishing weights. Recent regulations in some states have restricted the use of lead ammunition on certain upland game hunting areas, as well as lead fishing tackle in areas frequented by common loons and trumpeter swans. A variety of alternatives to lead are available for use in hunting, shooting sports, and fishing activities.

  7. Lead Exposure: Weighing Down IQ.

    Science.gov (United States)

    Science News, 1979

    1979-01-01

    Researchers at Harvard Medical School and the Children's Hospital Medical Center in Boston have found that children exposed to high but well below identified toxic levels of lead show significantly lower IQ levels and a higher incidence of undesirable classroom behavior than do children with low levels of lead exposure. (Author/BB)

  8. Lead Exposure and Child Behavior.

    Science.gov (United States)

    Sciarillo, William G.; And Others

    1992-01-01

    Provides evidence of detrimental effects of lead exposure on child behavior at levels typical of present-day exposure. Behavior and lead-blood level were examined for 201 African-American children aged 2 through 5 years. A standardized parent report measure and consideration of maternal morale are features of study methodology. (SLD)

  9. Lead poisoning from souvenir earthenware.

    Science.gov (United States)

    Hellström-Lindberg, Eva; Björklund, Andreas; Karlson-Stiber, Christine; Harper, Pauline; Seldén, Anders I

    2006-02-01

    A case of massive lead poisoning from juice contained in a Greek earthenware jug as well as six satellite cases of high lead exposure of similar origin is reported. The intoxicated patient was successfully treated with dimercaptosuccinic acid. Ceramic producers should adhere to the longstanding European legislation.

  10. Lead-free primary explosives

    Science.gov (United States)

    Huynh, My Hang V.

    2010-06-22

    Lead-free primary explosives of the formula (cat).sub.Y[M.sup.II(T).sub.X(H.sub.2O).sub.6-X].sub.Z, where T is 5-nitrotetrazolate, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  11. Leading change: a concept analysis.

    Science.gov (United States)

    Nelson-Brantley, Heather V; Ford, Debra J

    2017-04-01

    To report an analysis of the concept of leading change. Nurses have been called to lead change to advance the health of individuals, populations, and systems. Conceptual clarity about leading change in the context of nursing and healthcare systems provides an empirical direction for future research and theory development that can advance the science of leadership studies in nursing. Concept analysis. CINAHL, PubMed, PsycINFO, Psychology and Behavioral Sciences Collection, Health Business Elite and Business Source Premier databases were searched using the terms: leading change, transformation, reform, leadership and change. Literature published in English from 2001 - 2015 in the fields of nursing, medicine, organizational studies, business, education, psychology or sociology were included. Walker and Avant's method was used to identify descriptions, antecedents, consequences and empirical referents of the concept. Model, related and contrary cases were developed. Five defining attributes of leading change were identified: (a) individual and collective leadership; (b) operational support; (c) fostering relationships; (d) organizational learning; and (e) balance. Antecedents were external or internal driving forces and organizational readiness. The consequences of leading change included improved organizational performance and outcomes and new organizational culture and values. A theoretical definition and conceptual model of leading change were developed. Future studies that use and test the model may contribute to the refinement of a middle-range theory to advance nursing leadership research and education. From this, empirically derived interventions that prepare and enable nurses to lead change to advance health may be realized. © 2016 John Wiley & Sons Ltd.

  12. Blood Test: Lead (For Parents)

    Science.gov (United States)

    ... Important? Top 10 Homework Tips Raising Confident Kids Blood Test: Lead KidsHealth > For Parents > Blood Test: Lead Print A A A What's in this ... locate a vein Helping Your Child Having a blood test is relatively painless. Still, many children are afraid ...

  13. Biosorption of lead phosphates by lead-tolerant bacteria as a mechanism for lead immobilization.

    Science.gov (United States)

    Rodríguez-Sánchez, Viridiana; Guzmán-Moreno, Jesús; Rodríguez-González, Vicente; Flores-de la Torre, Juan Armando; Ramírez-Santoyo, Rosa María; Vidales-Rodríguez, Luz Elena

    2017-08-01

    The study of metal-tolerant bacteria is important for bioremediation of contaminated environments and development of green technologies for material synthesis due to their potential to transform toxic metal ions into less toxic compounds by mechanisms such as reduction, oxidation and/or sequestration. In this study, we report the isolation of seven lead-tolerant bacteria from a metal-contaminated site at Zacatecas, México. The bacteria were identified as members of the Staphylococcus and Bacillus genera by microscopic, biochemical and 16S rDNA analyses. Minimal inhibitory concentration of these isolates was established between 4.5 and 7.0 mM of Pb(NO3)2 in solid and 1.0-4.0 mM of Pb(NO3)2 in liquid media. A quantitative analysis of the lead associated to bacterial biomass in growing cultures, revealed that the percentage of lead associated to biomass was between 1 and 37% in the PbT isolates. A mechanism of complexation/biosorption of lead ions as inorganic phosphates (lead hydroxyapatite and pyromorphite) in bacterial biomass, was determined by Fourier transform infrared spectroscopy and X-ray diffraction analyses. Thus, the ability of the lead-tolerant isolates to transform lead ions into stable and highly insoluble lead minerals make them potentially useful for immobilization of lead in mining waste.

  14. Experimental model of lead nephropathy

    Energy Technology Data Exchange (ETDEWEB)

    Khalil-Manesh, F.; Gonick, H.C. (Cedars-Sinai Medical Center, Los Angeles, CA (United States)); Cohen, A. (UCLA-Harbor General Hospital, Torrance, CA (United States)); Bergamaschi, E.; Mutti, A. (Univ. of Parma (Italy))

    1992-06-01

    Male Sprague-Dawley rats were exposed to high-dose (0.5%) lead acetate for periods ranging from 1 to 9 months; then lead exposure was discontinued, and animals were sacrificed after 12 months. Two additional groups of low-dose (0.01%) and high-dose (0.5%) rats were exposed to lead for 6 months, then lead was discontinued and the rats were treated with three 5-day courses of 0.5% DMSA (dimercaptosuccinic acid) over the next 6 months. Low-dose lead-treated rats showed no significant pathological changes with or without DMSA treatment, but exhibited a significant increase in GFR after DMSA. High-dose lead-treated animals showed no functional or pathological changes when lead exposure was discontinued after 1 month. However, when duration of exposure was 6 or 9 months, GFR was decreased and serum creatinine and urea nitrogen were increased as compared to controls. Tubulointerstitial disease was severe. Administration of DMSA resulted in an improvement in GFR and a decrease in albuminuria, together with a reduction in size and number of nuclear inclusion bodies in proximal tubules. However, tubulointerstitial scarring was only minimally reduced. It may be concluded that, except for brief initial exposure, discontinuation of high-dose lead exposure fails to reverse lead-induced renal damage. Treatment with the chelator, DMSA, improves renal function but has less effect on pathological alterations. As GFR improved after DMSA treatment in both low-dose and high-dose lead-treated rats, irrespective of the degree of pathological alterations, it may be concluded that the DMSA effect is most likely mediated by hemodynamic changes.

  15. Environmental lead hazard to children.

    Science.gov (United States)

    Mittal, S K

    1992-01-01

    Clinically evident lead poisoning is rare in Indian children but is more common than in adults. In children, lead poisoning may appear as fever, seizures, anemia, or abdominal pain, while in adults it is more likely to manifest as chronic minor peripheral neuropathy or gum pigmentation. Children with acute lead poisoning can be treated with chelators such as EDTA and BAL, but many are left with permanent brain damage. The most common sources of acute lead poisoning in Indian children are inhalation of fumes from burned car batteries, ingestion of flaking paint, consuming food cooked in cheap aluminum or brass utensils, and eating contaminated soil. The sources of chronic lead poisoning are water from lead pipes and fumes from industrial or automotive exhaust. Another common source in India is application of "kajjal" to children's eyes. Sources of lead in Western countries, such as drinking water, canned food, residential paint, automotive fuel, and ambient air quality, are regulated by law. None of these are regulated in India.

  16. Correlation between lead in plasma and other indicators of lead exposure among lead-exposed workers.

    Science.gov (United States)

    Hirata, M; Yoshida, T; Miyajima, K; Kosaka, H; Tabuchi, T

    1995-01-01

    In order to clarify the bioavailability of lead in plasma (PbP), we performed a study on five workers in a Japanese factory manufacturing lead glass-based paints. Blood and urine samples were obtained over a period of 15 months, during which time the workers took it in turns to perform sifting work (with the highest level of lead exposure) for 1-month periods. A total of 75 sets of blood and urine samples were thus obtained. We determined whole blood lead (PbB), PbP, Urinary coproporphyrin (CPU), urinary delta-aminolevulinic acid (ALAU), urinary lead (PbU) and ALA in plasma (ALAP). In the 15 sets of samples obtained at the end of the period with a high level of lead exposure, PbP correlated significantly with ALAU, CPU, PbU and ALAP, but PbB correlated significantly only with PbU. In the 60 sets of samples obtained following a low level of lead exposure, correlation coefficients between the concentrations of PbP and of ALAU, CPU and PbU exceeded those between the concentrations of PbB and of ALAU, CPU and PbU. These findings indicate that PbP is a better dose indicator of lead biochemically available for heme synthesis and that PbU has a closer correlation with PbP than with PbB.

  17. Lead poisoning from Ayurvedic medicines.

    Science.gov (United States)

    Tsutsui, Rayji S; Van Schalkwyk, Johan; Spriggs, David

    2013-05-10

    A case of lead poisoning with established exposure to Ayurvedic medicines is presented. This patient migrated from India to New Zealand 8 years previously. He regularly visits India where he purchases "herbal remedies" for his wellbeing.

  18. Lead poisoning after gunshot wound

    Directory of Open Access Journals (Sweden)

    Paulo Roberto de Madureira

    2000-05-01

    Full Text Available CONTEXT: Despite the absence of symptoms in the majority of patients carrying lead bullet fragments in their bodies, there needs to be an awareness of the possible signs and symptoms of lead intoxication when bullets are lodged in large joints like knees, hips and shoulders. Such patients merit closer follow-up, and even surgical procedure for removing the fragments. OBJECTIVE: To describe a patient who developed clinical lead intoxication several years after a gunshot wound. DESIGN: Case report. CASE REPORT: A single white 23-year-old male, regular job as a bricklayer, with a history of chronic alcohol abuse, showed up at the emergency department complaining of abdominal pain with colic, weakness, vomiting and diarrhea with black feces. All the symptoms had a duration of two to three weeks, and had been recurrent for the last two years, with calming during interval periods of two to three weeks. Abdominal radiograms showed a bullet lodged in the left hip, with a neat bursogram of the whole synovial capsule. A course of chelating treatment using calcium versenate (EDTACaNa2 intravenously was started. After the chelation therapy the patient had recurrence of his symptoms and a radical solution for the chronic mobilization of lead was considered. A hip arthroplasty procedure was performed, leading to complete substitution of the left hip.

  19. Blood lead level as biomarker of environmental lead pollution in ...

    African Journals Online (AJOL)

    Research has demonstrated a positive link between the presence of lead in freshwater, sediments or food organisms and the onset of sub-lethal effects characterized by neurological defects, kidney dysfunction, endocrine disruption, reproductive/developmental defects, behavioural abnormalities and anemia in demersal ...

  20. Lead Contamination and Microbial Lead Tolerance in Soils at Major ...

    African Journals Online (AJOL)

    Devika

    effects of combined metals (lead, zinc, copper, manganese, iron) showed that at lower concentrations, metals ... battery manufacturing operations (Atuanya et al.,. 1999; Fagade and Adetutu, 1999). This study examined ... Soil samples for analyses were air-dried, sieved through a 2mm sieve and weighed. Microbial Isolation: ...

  1. CAN FLUORIDATION AFFECT WATER LEAD LEVELS AND LEAD NEUROTOXICITY?

    Science.gov (United States)

    Recent reports have attempted to show that certain approaches to fluoridating potable water is linked to increased levels of lead(II) in the blood. We examine these claims in light of the established science and critically evaluate their significance. The completeness of nexafluo...

  2. Inadvertent transarterial pacemaker lead placement

    Directory of Open Access Journals (Sweden)

    Ravi R. Bajaj

    2015-09-01

    Full Text Available We present a case of a 73-year-old patient with acute left-sided hemiparesis four months after right ventricular pacemaker insertion. Post-procedural electrocardiogram revealed a paced RBBB complex and an abnormal lead path on chest X-ray. Subsequent echocardiography and computed tomography showed left ventricular pacemaker malposition with retrograde passage to the punctured subclavian artery. We also discuss the utility of routine cardiac investigations post-insertion to identify signal lead malposition as well as management strategies once identified.

  3. OPAL 96 Blocks Lead Glass

    CERN Multimedia

    This array of 96 lead glass bricks formed part of the OPAL electromagnetic calorimeter. One half of the complete calorimeter is shown in the picture above. There were 9440 lead glass counters in the OPAL electromagnetic calorimeter. These are made of Schott type SF57 glass and each block weighs about 25 kg and consists of 76% PbO by weight. Each block has a Hamamatsu R2238 photomultiplier glued on to it. The complete detector was in the form of a cylinder 7m long and 6m in diameter. It was used to measure the energy of electrons and photons produced in LEP interactions.

  4. Chronic lead intoxication; Chronische Bleiintoxikation

    Energy Technology Data Exchange (ETDEWEB)

    Wieseler, B.; Leng, G. [Duesseldorf Univ. (Germany). Inst. fuer Hygiene; Lenz, S.; Schultz, C. [Klinikum Remscheid GmbH, Remscheid (Germany); Wilhelm, M. [Bochum Univ. (Germany). Inst. fuer Hygiene, Sozial- und Umweltmedizin

    1999-02-01

    The case of a female 68 years old patient is described. Here, a chronic lead intoxication was diagnosed after a two year old medical history with increasing attacks of colic-like abdominal pain often described as life-threatening. After repeated hospitalizations and intensive search for the cause of the symptoms, porphyria and anemia was found to be a sign of a chronic lead poisoning. The blood lead concentrations were always about a level of 600 {mu}g/L. The source of exposure could not be found by now. Neither home inspection nor environmental investigations have shown a recent source of lead intake by the patient. However, a possible occupational source of lead exposure at a blast furnace was established by anamnesis for 1952 to 1962. Thus, osteoporosis induced lead mobilisation was suspected. Noticeable are the results of the six abdominal survey radiographies taken during hospitalization within one year; three radiographies were taken following clinical admission and three before discharge of the patient. In comparison, the course shows a chronic relapsing alimentary supply from metallic particles of unknown genesis. The patient was treated with the sodium salt of 2,3-dimercapto-1-propansulfonic acid (DMPS, Dimaval{sup TM}). She was free of complain afterwards. Following therapy, the blood lead concentrations fell under a level of 400 {mu}m/L, but after several weeks the lead level raised up to the original level of 600 {mu}g/L. (orig.) [Deutsch] Es wird eine 68jaehrige Patientin vorgestellt, bei der nach fast zweijaehriger Krankengeschichte, die gekennzeichnet war durch rezidivierende, teils als lebensbedrohlich geschilderte Bauchkoliken, eine chronische Bleiintoxikation diagnostiziert wurde. Erst nach wiederholten stationaeren Krankenhausaufenthalten mit intensiver Suche nach der Krankheitsursache wurden das Krankheitsbild und die Laborwerte durch Zusatzuntersuchungen ergaenzt, so dass sich in der festgestellten Porphyrie und Anaemie die Diagnose der

  5. Registered Nurses Leading Innovative Changes

    Science.gov (United States)

    Thomas, Timothy W; Seifert, Patricia C; Joyner, Jane Clare

    2016-09-30

    As innovators, all registered nurses (RNs) act as agents of change to drive processes and policy and leverage technology to prove better, more affordable care for individuals and the community. The authors consider examples of RNs leading innovative ideas and practices to create new knowledge; develop healthcare policies and practices; improve the quality of care; and advance health information technology. This article describes a number of key innovation goals identified by the American Nurses Association Professional Issues Panel, Barriers to RN Scope of Practice, discusses relevant literature related to overcoming barriers to innovation, and identifies recommendations for leading innovative change to achieve innovation goals.

  6. Leading in a Technological Age

    Science.gov (United States)

    Yadgir, Sheri A.

    2011-01-01

    Technology is advancing more rapidly than at any time in history since the beginning of the Industrial Revolution. In fact, experts say that the world is leaving the Industrial Age of the 20th century and entering an Information Age that will lead into the future. These advances mean that important changes are being made in all areas of life--and…

  7. OPAL Various Lead Glass Blocks

    CERN Multimedia

    These lead glass blocks were part of a CERN detector called OPAL (one of the four experiments at the LEP particle detector). OPAL uses some 12 000 blocks of glass like this to measure particle energies in the electromagnetic calorimeter. This detector measured the energy deposited when electrons and photons were slowed down and stopped.

  8. Blood Lead and Reading Readiness

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2013-08-01

    Full Text Available Investigators at the University of Maryland School of Nursing, Johns Hopkins School of Public Health, and Department of Health, Providence, Rhode Island, evaluated the relationship between reading readiness test scores for children attending public kindergarten in Providence, RI, and state health department records of blood lead levels (BLLs.

  9. Developments in lead-acid batteries: a lead producer's perspective

    Science.gov (United States)

    Frost, P. C.

    Rapid progress is being made in many aspects of materials, design and construction for lead-acid batteries. Much of this work has taken place under the auspices of the Advanced Lead-Acid Battery Consortium (ALABC). From the general tone of the literature, it seems likely that several of these developments will be adopted in commercial products, and that there will be cross-fertilization between the emerging electric vehicle (EV) battery technology and the starting, lighting and ignition (SLI) battery. Given the impetus for improvement from several different factors, the development process appears to be accelerating. To those not intimately involved in the battery design and specification process, it is not clear which of the possible developments will make it from the laboratory to general commercial adoption. Some of the possible changes in materials, design and construction could have an impact on the recovery, recycling, smelting and refining of lead-acid batteries. Some of the possible developments are outlined and their possible impact is discussed. It is likely that negative effects may be minimized if battery developments are considered from other perspectives, largely based on the overall life-cycle, as early in the design phase of new products as possible. Three strategies for minimizing undesirable effects are advocated: first, improved communication between car manufacturers, battery manufacturers and lead producers second, use of life-cycle analysis (LCA) to identify and optimize all attributes of the product throughout its life-cycle third, concerted and coordinated action to deal with issues important to the industry once trends are identified.

  10. Lead-antimony alloys for electrode supports for lead accumulators

    Energy Technology Data Exchange (ETDEWEB)

    Dalibard, G.; Viaud, N.

    1984-04-17

    The grain size and resistance to corrosion of lead-antimony alloys containing less than 4% of antimony and 0.005 to 0.1% copper, are improved by incorporating therein from 0.001 to 0.1% of a mixture of rare earths, preferably misch metal. The alloys may also contain up to 0.5% arsenic or up to 0.8% of tin.

  11. Lead and Drinking Water from Private Wells

    Science.gov (United States)

    ... type=”submit” value=”Submit” /> Healthy Water Home Lead and Drinking Water from Private Wells Recommend on ... remove lead from my drinking water? What is lead? Lead is a naturally occurring bluish-gray metal ...

  12. Deformation properties of lead isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Tolokonnikov, S. V.; Borzov, I. N.; Lutostansky, Yu. S.; Saperstein, E. E., E-mail: saper43-7@mail.ru [National Research Center Kurchatov Institute (Russian Federation)

    2016-01-15

    The deformation properties of a long lead isotopic chain up to the neutron drip line are analyzed on the basis of the energy density functional (EDF) in the FaNDF{sup 0} Fayans form. The question of whether the ground state of neutron-deficient lead isotopes can have a stable deformation is studied in detail. The prediction of this deformation is contained in the results obtained on the basis of the HFB-17 and HFB-27 Skyrme EDF versions and reported on Internet. The present analysis reveals that this is at odds with experimental data on charge radii and magnetic moments of odd lead isotopes. The Fayans EDF version predicts a spherical ground state for all light lead isotopes, but some of them (for example, {sup 180}Pb and {sup 184}Pb) prove to be very soft—that is, close to the point of a phase transition to a deformed state. Also, the results obtained in our present study are compared with the predictions of some other Skyrme EDF versions, including SKM*, SLy4, SLy6, and UNE1. By and large, their predictions are closer to the results arising upon the application of the Fayans functional. For example, the SLy4 functional predicts, in just the same way as the FaNDF{sup 0} functional, a spherical shape for all nuclei of this region. The remaining three Skyrme EDF versions lead to a deformation of some light lead isotopes, but their number is substantially smaller than that in the case of the HFB-17 and HFB-27 functionals. Moreover, the respective deformation energy is substantially lower, which gives grounds to hope for the restoration of a spherical shape upon going beyond the mean-field approximation, which we use here. Also, the deformation properties of neutron-rich lead isotopes are studied up to the neutron drip line. Here, the results obtained with the FaNDF{sup 0} functional are compared with the predictions of the HFB-17, HFB-27, SKM*, and SLy4 Skyrme EDF versions. All of the EDF versions considered here predict the existence of a region where neutron

  13. Leading Hadron Production at HERA

    Directory of Open Access Journals (Sweden)

    Buniatyan Armen

    2013-06-01

    Full Text Available Data from the recent measurements of very forward baryon and photon production with the H1 and ZEUS detectors at electron-proton collider HERA are presented and compared to the theoretical calculations and Monte Carlo models. Results are presented of the production of leading protons, neutrons and photons in deep inelastic scattering (ep → e' pX, ep → e'nX, ep → e'γX as well as the leading neutron production in the photoproduction of dijets (ep → ejjXn. The forward baryon and photon results from the H1 and ZEUS Experiments are compared also with the models of the hadronic interactions of high energy Cosmic Rays. The sensitivity of the HERA data to the differences between the models is demonstrated.

  14. Anthropogenic lead isotopes in Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Rosman, K.J.R.; Chisholm, W. [Curtin Univ. of Technology, Bentley (Australia); Boutron, C.F. [Laboratoire de Glaciologie et Geophysique de l`Environnement du CNRS, St. Martin d`Heres (France)]|[Domaine Universitaire, Grenoble (France); Candelone, J.P. [Laboratoire de Glaciologie et Geophysique de l`Environnement du CNRS, St. Martin d`Heres (France); Patterson, C.C. [California Institute of Technology, Pasadena, CA (United States)

    1994-12-01

    The authors present results from the first Pb isotopic study of the sources of lead in snow samples from the Antarctic. Samples of recent snow fields were compared with measurements of samples taken from deep cores, and they reveal that recent snows show pronounced influence of anthropogenic sources. These results are independent of geochemical arguments based on influences of Al, Na, or SO{sub 4}.

  15. How to lead complex situations

    DEFF Research Database (Denmark)

    Hansen, Michael Pingel

    2013-01-01

    The military leader is experiencing increasingly more complex situations, whether it is as leader in a foreign combat environment or in the home-based public administration. Complex situations like these call for a special set of managerial responses and a special way of leading organisations....... The proposition of this article is that the methods that drive innovative processes, strengthening the creative culture, are necessary to manage complex situations in military contexts....

  16. Picornavirus infection leading to immunosuppression

    OpenAIRE

    Cusick, Matthew F; Libbey, Jane E.; Fujinami, Robert S.

    2014-01-01

    Viruses, such as HIV, hepatitis A, poliovirus, coxsackievirus B3 and foot-and-mouth disease virus, use a variety of mechanisms to suppress the human immune system in order to evade clearance by the host. Therefore, investigating how a few changes in the viral genome of a nonlethal virus can lead to an alteration in disease, from survivable to immunosuppression and death, would provide valuable information into viral pathogenesis. In addition, we propose that gaining a better insight into how ...

  17. Leading Indian Business-Groups

    Directory of Open Access Journals (Sweden)

    Maria Alexandrovna Vorobyeva

    2016-01-01

    Full Text Available The goal of this paper is to investigate the evolution of the leading Indian business-groups under the conditions of economical liberalization. It is shown that the role of modern business-groups in the Indian economy is determined by their high rate in the gross domestic product (GDP, huge overall actives, substantial pert in the e[port of goods and services, as well as by their activities in modern branch structure formatting, and developing labor-intensive and high-tech branches. They strongly influence upon economical national strategies, they became a locomotive of internationalization and of transnationalization of India, the basis of the external economy factor system, the promoters of Indian "economical miracle" on the world scene, and the dynamical segment of economical and social development of modern India. The tendencies of the development of the leading Indian business groups are: gradual concentration of production in few clue sectors, "horizontal" structure, incorporation of the enterprises into joint-stock structure, attraction of hired top-managers and transnationaliziation. But against this background the leading Indian business-groups keep main traditional peculiarities: they mostly still belong to the families of their founders, even today they observe caste or communal relations which are the basis of their non-formal backbone tides, they still remain highly diversificated structures with weak interrelations. Specific national ambivalence and combination of traditions and innovations of the leading Indian business-groups provide their high vitality and stability in the controversial, multiform, overloaded with caste and confessional remains Indian reality. We conclude that in contrast to the dominant opinion transformation of these groups into multisectoral corporations of the western type is far from completion, and in the nearest perspective they will still possess all their peculiarities and incident social and economical

  18. The LHC Lead Injector Chain

    CERN Document Server

    Beuret, A; Blas, A; Burkhardt, H; Carli, Christian; Chanel, M; Fowler, A; Gourber-Pace, M; Hancock, S; Hourican, M; Hill, C E; Jowett, John M; Kahle, K; Küchler, D; Lombardi, A M; Mahner, E; Manglunki, Django; Martini, M; Maury, S; Pedersen, F; Raich, U; Rossi, C; Royer, J P; Schindl, Karlheinz; Scrivens, R; Sermeus, L; Shaposhnikova, Elena; Tranquille, G; Vretenar, Maurizio; Zickler, T

    2004-01-01

    A sizeable part of the LHC physics programme foresees lead-lead collisions with a design luminosity of 1027 cm-2 s-1. This will be achieved after an upgrade of the ion injector chain comprising Linac3, LEIR, PS and SPS machines [1,2]. Each LHC ring will be filled in 10 min by almost 600 bunches, each of 7×107 lead ions. Central to the scheme is the Low Energy Ion Ring (LEIR) [3,4], which transforms long pulses from Linac3 into high-brilliance bunches by means of multi-turn injection, electron cooling and accumulation. Major limitations along the chain, including space charge, intrabeam scattering, vacuum issues and emittance preservation are highlighted. The conversion from LEAR (Low Energy Antiproton Ring) to LEIR involves new magnets and power converters, high-current electron cooling, broadband RF cavities, and a UHV vacuum system with getter (NEG) coatings to achieve a few 10-12 mbar. Major hardware changes in Linac3 and the PS are also covered. An early ion scheme with fewer bunches (but each at nominal...

  19. Relational Leading and Dialogic Process

    DEFF Research Database (Denmark)

    Hansen, Lone Hersted

    The Ph.D. thesis contributes to a relational orientation to leading, emphasizing leadership as a shared, collaborative and co-creative activity. In this paradigm major emphasis is put on dialogue and interaction. Inspired by social constructionist ideas, the thesis considers approaches to learning...... with the thesis, dialogically based practices inspired by action research with the aim to enhance collaborative knowledge building, reflexivity and dialogical skills in groups and teams were carried out, analyzed and documented. Participants included school principals, leaders of kindergartens, teachers...

  20. Lead-nickel electrochemical batteries

    CERN Document Server

    Glaize, Christian

    2012-01-01

    The lead-acid accumulator was introduced in the middle of the 19th Century, the diverse variants of nickel accumulators between the beginning and the end of the 20th Century. Although old, these technologies are always very present on numerous markets. Unfortunately they are still not used in optimal conditions, often because of the misunderstanding of the internal electrochemical phenomena.This book will show that batteries are complex systems, made commercially available thanks to considerable amounts of scientific research, empiricism and practical knowledge. However, the design of

  1. Elevation leads to altruistic behavior.

    Science.gov (United States)

    Schnall, Simone; Roper, Jean; Fessler, Daniel M T

    2010-03-01

    Feelings of elevation, elicited by witnessing another person perform a good deed, have been hypothesized to motivate a desire to help others. However, despite growing interest in the determinants of prosocial behavior, there is only limited evidence that elevation leads to increases in altruistic behavior. In two experiments, we tested the relationship between elevation and helping behavior. Prior to measuring helping behavior, we measured elevation among participants in an elevation-inducing condition and control conditions in order to determine whether witnessing altruistic behavior elicited elevation. In Experiment 1, participants experiencing elevation were more likely to volunteer for a subsequent unpaid study than were participants in a neutral state. In Experiment 2, participants experiencing elevation spent approximately twice as long helping the experimenter with a tedious task as participants experiencing mirth or a neutral emotional state. Further, feelings of elevation, but not feelings of amusement or happiness, predicted the amount of helping. Together, these results provide evidence that witnessing another person's altruistic behavior elicits elevation, a discrete emotion that, in turn, leads to tangible increases in altruism.

  2. All roads lead to Meyrin

    CERN Multimedia

    Communication locale

    2011-01-01

    Tous les chemins mènent à Meyrin - All roads lead to Meyrin From 29 September to 16 October, 2011, come to the Salle Antoine Verchère in Meyrin for Tous les chemins mènent à Meyrin. The celebration will include an exposition as well as a theatrical performance about Meyrin, the first satellite city in Switzerland. With the help of the memories and testimonies from the people of Meyrin, Tous les chemins mènent à Meyrin is putting the collective memories of the commune on display. It is an occasion for everyone, whether you're from near or far, to find out how all the roads lead to Meyrin.  Salle Antoine-Verchère Route de Meyrin 294 – 1217 Meyrin Tram 18 – Stop: Meyrin Village Thursdays / Fridays / Saturdays at 8pm Sundays at 5pm Regular ticket: CHF 15.- Concession ticket (students, chômeurs, AVS, AI): CHF 12.- Children up to 16: CHF 10.- Family ticket: CHF 35.-

  3. Helping Parents Prevent Lead Poisoning. ERIC Digest.

    Science.gov (United States)

    Binns, Helen J.; Ricks, Omar Benton

    Children are at greater risk than adults for lead poisoning because children absorb lead more readily than adults, and a small amount of lead in children's bodies can do a great deal of harm. Some of the causes and effects of childhood lead poisoning and suggests some lead poisoning prevention strategies that parent educators can share with…

  4. Anti-cancer Lead Molecule

    KAUST Repository

    Sagar, Sunil

    2014-04-17

    Derivatives of plumbagin can be selectively cytotoxic to breast cancer cells. Derivative `A` (Acetyl Plumbagin) has emerged as a lead molecule for testing against estrogen positive breast cancer and has shown low hepatotoxicity as well as overall lower toxicity in nude mice model. The toxicity of derivative `A` was determined to be even lower than vehicle control (ALT and AST markers). The possible mechanism of action identified based on the microarray experiments and pathway mapping shows that derivative `A` could be acting by altering the cholesterol-related mechanisms. The low toxicity profile of derivative `A` highlights its possible role as future anti-cancer drug and/or as an adjuvant drug to reduce the toxicity of highly toxic chemotherapeutic drugs

  5. Multi-lead heat sink

    Science.gov (United States)

    Roose, Lars D.

    1984-01-01

    The disclosure relates to a heat sink used to protect integrated circuits from the heat resulting from soldering them to circuit boards. A tubular housing contains a slidable member which engages somewhat inwardly extending connecting rods, each of which is rotatably attached at one end to the bottom of the housing. The other end of each rod is fastened to an expandable coil spring loop. As the member is pushed downward in the housing, its bottom edge engages and forces outward the connecting rods, thereby expanding the spring so that it will fit over an integrated circuit. After the device is in place, the member is slid upward and the spring contracts about the leads of the integrated circuit. Soldering is now conducted and the spring absorbs excess heat therefrom to protect the integrated circuit. The placement steps are repeated in reverse order to remove the heat sink for use again.

  6. Lead-Based Paint and Demolition

    Science.gov (United States)

    The Lead Renovation, Repair, and Painting Rule does not apply to total demolition of a structure. Learn about EPA recommended lead-safe practices during total demolition activities to prevent and minimize exposure to lead.

  7. [XANES study of lead speciation in duckweed].

    Science.gov (United States)

    Chu, Bin-Bin; Luo, Li-Qiang; Xu, Tao; Yuan, Jing; Sun, Jian-Ling; Zeng, Yuan; Ma, Yan-Hong; Yi, Shan

    2012-07-01

    Qixiashan lead-zinc mine of Nanjing was one of the largest lead zinc deposits in East China Its exploitation has been over 50 years, and the environmental pollution has also been increasing. The lead concentration in the local environment was high, but lead migration and toxic mechanism has not been clear. Therefore, biogeochemistry research of the lead zinc mine was carried out. Using ICP-MS and Pb-L III edge XANES, lead concentration and speciation were analyzed respectively, and duckweed which can tolerate and enriched heavy metals was found in the pollution area. The results showed that the lead concentration of duckweed was 39.4 mg x kg(-1). XANES analysis and linear combination fit indicated that lead stearate and lead sulfide accounted for 65% and 36.9% respectively in the lead speciation of duckweed, suggesting that the main lead speciation of duckweed was sulfur-containing lead-organic acid.

  8. Basic Information about Lead in Drinking Water

    Science.gov (United States)

    ... Health) Lead can also be transmitted through breast milk. Read more on lead exposure in pregnancy and lactating women (PDF) (302 pp, 4.3 MB, About PDF ) . Adults Lead is also harmful to adults. Adults exposed ...

  9. The identification of lead ammunition as a source of lead exposure in First Nations: The use of lead isotope ratios

    Energy Technology Data Exchange (ETDEWEB)

    Tsuji, Leonard J.S. [Department of Environment and Resource Studies, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)], E-mail: ljtsuji@fes.uwaterloo.ca; Wainman, Bruce C. [Faculty of Health Sciences, McMaster University, Hamilton, Ontario, L8N 3Z5 (Canada); Martin, Ian D. [Department of Environment and Resource Studies, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Sutherland, Celine [Attawapiskat First Nation Health Services, Attawapiskat, Ontario, P0L 1A0 (Canada); Weber, Jean-Philippe; Dumas, Pierre [Centre de toxicologie, Institut national de sante publique du Quebec, Quebec City, Quebec, G1V 5B3 (Canada); Nieboer, Evert [Faculty of Health Sciences, McMaster University, Hamilton, Ontario, L8N 3Z5 (Canada); Institute of Community Medicine, University of Tromso, Tromso N-9037 (Norway)

    2008-04-15

    The use of lead shotshell to hunt water birds has been associated with lead-contamination in game meat. However, evidence illustrating that lead shotshell is a source of lead exposure in subsistence hunting groups cannot be deemed definitive. This study seeks to determine whether lead shotshell constitutes a source of lead exposure using lead isotope ratios. We examined stable lead isotope ratios for lichens, lead shotshell and bullets, and blood from residents of Fort Albany and Kashechewan First Nations, and the City of Hamilton, Ontario, Canada. Data were analyzed using ANOVA and regression analyses. ANOVA of isotope ratios for blood revealed significant differences with respect to location, but not sex. Hamilton differed from both Kashechewan and Fort Albany; however, the First Nations did not differ from each other. ANOVA of the isotope ratios for lead ammunition and lichens revealed no significant differences between lichen groups (north and south) and for the lead ammunition sources (pellets and bullets). A plot of {sup 206}Pb/{sup 204}Pb and {sup 206}Pb/{sup 207}Pb values illustrated that lichens and lead ammunition were distinct groupings and only the 95% confidence ellipse of the First Nations group overlapped that of lead ammunition. In addition, partial correlations between blood-lead levels (adjusted for age) and isotope ratios revealed significant (p < 0.05) positive correlations for {sup 206}Pb/{sup 204}Pb and {sup 206}Pb/{sup 207}Pb, and a significant negative correlation for {sup 208}Pb/{sup 206}Pb, as predicted if leaded ammunition were the source of lead exposure. In conclusion, lead ammunition was identified as a source of lead exposure for First Nations people; however, the isotope ratios for lead shotshell pellets and bullets were indistinguishable. Thus, lead-contaminated meat from game harvested with lead bullets may also be contributing to the lead body burden.

  10. Association of Lead Levels and Cerebral Palsy

    OpenAIRE

    Neha Bansal MD; Anju Aggarwal MD, FIAP, MNAMS; M. M. A. Faridi MD, FIAP, MNAMS; Tusha Sharma PhD; B. D. Baneerjee PhD

    2017-01-01

    Background: Cerebral palsy is a common motor disability in childhood. Raised lead levels affect cognition. Children with cerebral palsy may have raised lead levels, further impairing their residual cognitive motor and behavioral abilities. Environmental exposure and abnormal eating habits may lead to increased lead levels. Aims and Objectives: To measure blood lead levels in children with cerebral palsy and compare them with healthy neurologically normal children. To correlate blood lead leve...

  11. Evaluation and management of lead exposure

    OpenAIRE

    Kim, Hwan-Cheol; Jang, Tae-Won; Chae, Hong-Jae; Choi, Won-Jun; Ha, Mi-Na; Ye, Byeong-Jin; Kim, Byoung-Gwon; Jeon, Man-Joong; Kim, Se-yeong; Hong, Young-Seoub

    2015-01-01

    Lead, which is widely used in industry, is a common element found in low concentrations in the Earth?s crust. Implementations to reduce environmental lead concentrations have resulted in a considerable reduction of lead levels in the environment (air) and a sustained reduction in the blood lead levels of the average citizen. However, people are still being exposed to lead through a variety of routes in everyday commodities. Lead causes health problems such as toxicity of the liver, kidneys, h...

  12. Blood lead levels and cumulative blood lead index (CBLI) as predictors of late neurodevelopment in lead poisoned children

    Science.gov (United States)

    Nie, Linda H.; Wright, Robert O.; Bellinger, David C.; Hussain, Javed; Amarasiriwardena, Chitra; Chettle, David R.; Pejović-Milić, Ana; woolf, Alan; Shannon, Michael

    2011-01-01

    Objective To find the best lead exposure assessment marker for children. Methods We recruited 11 children, calculated a cumulative blood lead index (CBLI) for the children, measured their concurrent BLL, assessed their development, and measured their bone lead level. Results Nine of 11 children had clinically significant neurodevelopment problems. CBLI and current blood lead level, but not the peak lead level, were significantly or marginally negatively associated with the full-scale IQ score. Conclusion Lead exposure at younger age significantly impacts a child’s later neurodevelopment. CBLI may be a better predictor of neurodevelopment than are current or peak blood lead levels. PMID:21827276

  13. Darwinian selection leads to Gaia.

    Science.gov (United States)

    Staley, Mark

    2002-09-07

    The Gaia hypothesis, in its strongest form, states that the Earth's atmosphere, oceans, and biota form a tightly coupled system that maintains environmental conditions close to optimal for life. According to Gaia theory, optimal conditions are intrinsic, immutable properties of living organisms. It is assumed that the role of Darwinian selection is to favor organisms that act to stabilize environmental conditions at these optimal levels. In this paper, an alternative form of Gaia theory based on more traditional Darwinian principles is proposed. In the new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions. A simple Daisyworld model is used to illustrate this convergence phenomenon. Sensitivity analysis of the Daisyworld model suggests that in stable ecosystems, the convergence of equilibrium and optimal conditions is inevitable, provided there are no externally driven shocks to the system. The end result may appear to be the product of a cooperative venture, but is in fact the outcome of Darwinian selection acting upon "selfish" organisms.

  14. Leading local politicians visit CERN

    CERN Multimedia

    2001-01-01

    Left to right:  Professor Maiani, Ernest Nycollin, Anne-Marie Comparini, and Jean Pépin surrounded by young PRAC. On the 13th of November leading local politicians : Mme Anne-Marie Comparini, Présidente du Conseil régional de Rhône-Alpes, M. Ernest Nycollin, Président du Conseil général de la Haute-Savoie et M. Jean Pépin, Président du Conseil général de l'Ain took part in a ceremony which featured the insertion of one of the first LHC magnets into its cryostat.  The department of l'Ain financed a large part of the contruction of building SMA 18 which will see intense activity during the assembly of LHC magnets over the next four years. The department of Haute-Savoie helped in the development of the ultrasonic welding machine for the superconducting cables and the conception of integrated circuits that will be used to measure temperature and pressure inside the magnets. T...

  15. Dietary exposure to lead in the Netherlands

    NARCIS (Netherlands)

    Boon PE; te Biesebeek JD; van Donkersgoed G; VVH; V&Z

    2017-01-01

    Uptake from the soil is the main route by which lead ends up in food. Lead in soil has its origin in both natural and anthropogenic sources. The lead concentration in food has decreased over the last decennia by the use of unleaded petrol and paint, and the replacement of lead water pipes.

  16. Lead Poisoning: A Need for Education.

    Science.gov (United States)

    Lipnickey, Susan Cross

    1981-01-01

    Each year approximately 200 children die of lead poisoning. Especially vulnerable to the toxic effects of lead poisoning are the nervous system, kidneys, and the bones. Physiological effects of lead on the school-age child, screening processes, and roles of school personnel in dealing with suspected victims of lead poisoning are discussed. (JN)

  17. Lead poisoning in captive wild animals

    Energy Technology Data Exchange (ETDEWEB)

    Zook, B.C.; Sauer, R.M.; Garner, F.M.

    1972-07-01

    Lead poisoning was diagnosed post-mortem in 34 simian primates, 11 parrots, and 3 Australian fruit bats at the National Zoological Park. Diagnoses were made by the finding of acid-fast intranuclear inclusion bodies in renal epithelia or hepatocytes and, in most cases, by finding excess lead in samples of liver. The estimated prevalence of lead intoxication among autopsied primates and parrots was 44% and 50% respectively. Leaded paint was found in many animal enclosures at this zoo and it was available to all the lead-poisoned animals in this study. The finding of renal intranuclear inclusion bodies in animals at several zoos, scattered reports of lead intoxication of animals dwelling in various zoos, the occurrence of leaded paint in many zoos and the high incidence of lead poisoning at this zoo, indicated that lead poisoning of zoo animals is much more common than was previously thought.

  18. Leading gravitational corrections and a unified universe

    DEFF Research Database (Denmark)

    Codello, Alessandro; Jain, Rajeev Kumar

    2016-01-01

    Leading order gravitational corrections to the Einstein-Hilbert action can lead to a consistent picture of the universe by unifying the epochs of inflation and dark energy in a single framework. While the leading local correction induces an inflationary phase in the early universe, the leading...... nonlocal term leads to an accelerated expansion of the universe at the present epoch. We argue that both the leading UV and IR terms can be obtained within the framework of a covariant effective field theory of gravity. The perturbative gravitational corrections therefore provide a fundamental basis...

  19. Lead poisoning in children: a case report.

    Science.gov (United States)

    Jouhadi, Zineb; Bensabbahia, Dalal; Chafiq, Fouad; Oukkache, Bouchra; Guebessi, Nisrine Bennani; Abdellah, El Abidi; Najib, Jilali

    2016-01-01

    Lead colic is a rare cause of abdominal pain. The diagnosis of lead poisoning is most often mentioned in at risk populations (children, psychotic). We report the case of a 2 year old child that was presented for acute abdomen. Abdominal plain radiograph showed multiple intra-colonic metallic particles and suggested lead poisoning diagnosis. Anamnesis found a notion of pica and consumption of peeling paint. Elevated blood lead levels (BLL) confirmed the diagnosis. The lead poisoning is a public health problem especially in children, but its manifestation by a lead colic is rare and could simulate an acute abdomen table.

  20. Clinical utility of computed electrocardiographic leads.

    Science.gov (United States)

    Batchvarov, Velislav N; Behr, Elijah R

    2014-01-01

    The standard 12-lead electrocardiogram (ECG) is only one of the possible ways to present the voltage differences between the nine recording electrodes. Other "non-conventional" leads may be constructed by physically connecting two or more electrodes in a different manner or by computation from the digital 12-lead ECG. Examples include bipolar or multipolar precordial leads and bipolar chest leads (between one precordial and one limb electrode). Such leads can remove or decrease noise originating from a limb cable/electrode that is present in the unipolar precordial leads. They can be diagnostically useful in Brugada syndrome and can display QRS fractionation that is not visible in the respective unipolar precordial or limb leads. Multipolar precordial leads sometimes display potentially useful information that is not visible in the respective unipolar leads and in bipolar leads computed from them. In conclusion, these computed ECG leads represent a potentially useful supplement to the conventional 12-lead ECG. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Lead Smelting and Refining at Kosaka Smelter

    National Research Council Canada - National Science Library

    MITSUNE, Yutaka; SATOH, Shigeki

    2007-01-01

      Kosaka Smelting and Refining Co., Ltd. operates lead smelting to produce electrolytic lead and to recover precious metals and bismuth with mainly secondary materials from copper smelter and zinc refinery...

  2. Some Lead Poisoning Tests May Be Faulty

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_165668.html Some Lead Poisoning Tests May Be Faulty But the majority of ... More Health News on Children's Health Laboratory Tests Lead Poisoning Recent Health News Related MedlinePlus Health Topics Children's ...

  3. Lead Poisoning in Remodeling of Old Homes

    Science.gov (United States)

    Barnes, Bart

    1973-01-01

    An article based on Dr. Muriel D. Wolf's study of elevated blood lead levels in children and adults present during the remodeling of old homes. Lead poisoning examples, symptoms, and precautions are given. (ST)

  4. WETTABILITY STUDIES OF LEAD-FREE SOLDERS

    African Journals Online (AJOL)

    2012-03-01

    Mar 1, 2012 ... language and behavioural problems [3]. Pregnant women and young children are particularly vul- nerable to lead ... However, this is controlled by a combination of several factors .... placement of tin-lead solders. Contact ...

  5. A Public Health Approach to Addressing Lead

    Science.gov (United States)

    Describes EPA’s achievements in reducing childhood lead exposures and emphasizes the need to continue actions to further reduce lead exposures, especially in those communities where exposures remain high.

  6. Observations on lead pollution in milk

    Energy Technology Data Exchange (ETDEWEB)

    Maffeo, G.; Renon, P.

    1976-08-01

    The problem of lead pollution in milk in highly industrialized areas (district of Milan) has been evaluated. Potentially dangerous rates of lead have been checked in milk, agricultural fields, fodders and entrails of slaughtered animals.

  7. Leading Change: Military Leadership in Civilian Organizations

    Science.gov (United States)

    2012-03-19

    lead to a very frustrating stalemate for both the military leader and the organization they join. LEADING CHANGE: MILITARY LEADERSHIP IN...Civilian adds, “For the military leader , managing a civilian workforce is different from leading military subordinates.”4 Military members must...must plot a course to get the organization on the right path. Finally, the leader must lead and manage change in their organization while keeping

  8. Lead exposure from aluminum cookware in Cameroon

    Energy Technology Data Exchange (ETDEWEB)

    Weidenhamer, Jeffrey D.; Kobunski, Peter A. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Kuepouo, Gilbert [Research and Education Centre for Development (CREPD), Yaounde (Cameroon); Corbin, Rebecca W. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Gottesfeld, Perry, E-mail: pgottesfeld@okinternational.org [Occupational Knowledge International, San Francisco, CA (United States)

    2014-10-15

    Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world. Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (< 1000 ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260 μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg.

  9. Developmental Effects of Lead Exposure in Children.

    Science.gov (United States)

    Tesman, Johanna Rich; Hills, Amanda

    1994-01-01

    This report presents an overview of research on childhood lead exposure and poisoning, and the related social issues. The report first summarizes the history of lead poisoning and its prevalence in the United States, and discusses the basis for recent changes in guidelines for lead exposure by the Centers for Disease Control (CDC). The report then…

  10. Hematological evaluation of lead intoxication in mallards

    Energy Technology Data Exchange (ETDEWEB)

    Mautino, M.; Bell, J.U.

    1987-01-01

    The measurement of blood lead has been the most widely accepted laboratory test for monitoring environmental lead exposure. Many technical difficulties are inherent in the precise quantification of blood lead at low concentrations and a margin of error of fifteen percent is not uncommon. Measurement of critical biochemical alterations resulting from lead exposure may provide a better indication of the toxic response of an individual than the actual measurement of blood lead. Lead exposure alters a number of enzymes resulting in impaired heme synthesis and an elevation or excretion of intermediates. Although the determination of blood lead has been the reference standard for monitoring lead exposure, the measurement of delta-aminolevulinic acid dehydratase activity (delta-ALAD) and free erythrocyte protoporphyrin concentrations (FEP) have been utilized to evaluate the extent of lead exposure in several species. In humans, there is a good correlation between both delta-ALAD and FEP and the deleterious effects seen following lead exposure. In avian species, investigators have measured elevated lead concentrations and an inhibition of delta-ALAD activity in lead-dosed mallards.

  11. Is Your Child Safe from Lead Poisoning?

    Centers for Disease Control (CDC) Podcasts

    2008-10-02

    In this podcast, Dr. Mary Jean Brown, chief of CDC's Lead Poisoning and Prevention Program, discusses the importance of testing children for lead poisoning, who should be tested, and what parents can do to prevent lead poisoning.  Created: 10/2/2008 by National Center for Environmental Health (NCEH).   Date Released: 10/2/2008.

  12. WETTABILITY STUDIES OF LEAD-FREE SOLDERS

    African Journals Online (AJOL)

    2012-03-01

    Mar 1, 2012 ... wettability, solder, lead, alloy, tin. 1. Introduction. Tin-lead solder has been the standard mate- rial used in electronic, chemical, automotive and other industries due to its low cost and unique material properties like low melting point, avail- ability etc. However, the toxicity of lead during industrial production of ...

  13. Lead poisoning of a marbled godwit

    Science.gov (United States)

    Locke, L.N.; Smith, M.R.; Windingstad, R.M.; Martin, S.J.

    1991-01-01

    A thin adult female marbled godwit (Limosa fedoa) found dead at Benton Lake National Wildlife Refuge, Montana, was found to have 17 ingested lead shot in its gizzard. Its liver contained 51.7 ppm lead (wet weight). Based on these necropsy findings a diagnosis of lead poisoning was made.

  14. Childhood Lead Poisoning: Blueprint for Prevention.

    Science.gov (United States)

    Rochow, K. W. James; Rapuano, Maria

    Current programs to deal with childhood lead poisoning, the primary environmental disease of U.S. children, screen individual children, treat those with serious cases of lead poisoning, and subsequently return children to hazardous environments. This approach has led to repeated diagnoses of lead poisoning. This handbook is designed to convince…

  15. Revision Surgery of Deep Brain Stimulation Leads.

    Science.gov (United States)

    Falowski, Steven M; Bakay, Roy A E

    2016-07-01

    Deep brain stimulation (DBS) is widely used for various movement disorders. DBS lead revisions are becoming more common as the indications and number of cases increases. Patients undergoing DBS lead revisions at a single institution were retrospectively analyzed based on diagnosis, reason for revision, where the lead was relocated, and surgical technique. We reviewed 497 consecutive DBS lead placements and found that there was need for 25 DBS lead revisions with at least six months of follow-up. Loss of efficacy and development of adverse effects over time were the most common reasons for lead revision across all diagnosis. Lead malfunction was the least common. Ten patients requiring 19 DBS lead revisions that underwent their original surgery at another institution were also analyzed. Surgical technique dictated replacing with a new lead while maintaining brain position and tract with the old lead until final placement. Methods to seal exposed wire were developed. Surgical technique, as well as variable options are important in lead revision and can be dictated based on reason for revision. Over time patients who have had adequate relief with DBS placement may experience loss of efficacy and development of adverse effects requiring revision of the DBS lead to maintain its effects. © 2016 International Neuromodulation Society.

  16. Historical View on Lead: Guidelines and Regulations.

    Science.gov (United States)

    Pohl, Hana R; Ingber, Susan Z; Abadin, Henry G

    2017-04-10

    Lead has been used in many commodities for centuries. As a result, human exposure has occurred through the production and use of these lead-containing products. For example, leaded gasoline, lead-based paint, and lead solder/pipes in water distribution systems have been important in terms of exposure potential to the general population. Worker exposures occur in various industrial activities such as lead smelting and refining, battery manufacturing, steel welding or cutting operations, printing, and construction. Some industrial locations have also been a source of exposure to the surrounding communities. While the toxicity of relatively high lead exposures has been recognized for centuries, modern scientific studies have shown adverse health effects at very low doses, particularly in the developing nervous system of fetuses and children. This chapter reflects on historical and current views on lead toxicity. It also addresses the development and evolution of exposure prevention policies. As discussed here, these lead policies target a variety of potential exposure routes and sources. The changes reflect our better understanding of lead toxicity. The chapter provides lead-related guidelines and regulations currently valid in the U. S. and in many countries around the world. The reader will learn about the significant progress that has been made through regulations and guidelines to reduce exposure and prevent lead toxicity.

  17. 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...

  18. Electrical polarization of lead bromide crystals. I

    NARCIS (Netherlands)

    Schoonman, A.; Macke, A.J.H.

    An attempt was made to measure electronic conductivity in lead bromide in equilibrium with lead, since experimental data on the cell −Pb/PbBr2/C+ in the literature are not consistent with existing theories. Combination of our results with published data for bromine-induced hole conduction in lead

  19. LEAD POISONING IN ANCIENT ROME 1. INTRODUCTION

    African Journals Online (AJOL)

    development of the region and the course of its history. 2. THE LEAD INDUSTRY IN ANCIENT ROME. 2.1 Lead production. From the 5th millennium BC ... production of olive oil were often made of or lined with lead (Cato,. De re rustica cv, lxvi). The wine fermentation process, too, often made use of casks or containers lined ...

  20. Distribution of Lead in Kerbside Soils

    African Journals Online (AJOL)

    NJD

    Lead in emissions from motor vehicles using leaded petrol are usually monitored by analysing gas samples. In view of the many problems associated with gas sampling, this project focussed on the analysis of lead in kerbside samples. To this end, soil .... was thoroughly mixed by shaking the soil in a clean plastic box.

  1. Early Reading Proficiency. Leading Indicator Spotlight

    Science.gov (United States)

    Musen, Lindsey

    2010-01-01

    In "Beyond Test Scores: Leading Indicators for Education," Foley and colleagues (2008) define leading indicators as those that "provide early signals of progress toward academic achievement" (p. 1) and stress that educators "need leading indicators to help them see the direction their efforts are going in and to take…

  2. A green lead hydrometallurgical process based on a hydrogen-lead oxide fuel cell.

    Science.gov (United States)

    Pan, Junqing; Sun, Yanzhi; Li, Wei; Knight, James; Manthiram, Arumugam

    2013-01-01

    The automobile industry consumed 9 million metric tons of lead in 2012 for lead-acid batteries. Recycling lead from spent lead-acid batteries is not only related to the sustainable development of the lead industry, but also to the reduction of lead pollution in the environment. The existing lead pyrometallurgical processes have two main issues, toxic lead emission into the environment and high energy consumption; the developing hydrometallurgical processes have the disadvantages of high electricity consumption, use of toxic chemicals and severe corrosion of metallic components. Here we demonstrate a new green hydrometallurgical process to recover lead based on a hydrogen-lead oxide fuel cell. High-purity lead, along with electricity, is produced with only water as the by-product. It has a >99.5% lead yield, which is higher than that of the existing pyrometallurgical processes (95-97%). This greatly reduces lead pollution to the environment.

  3. Eryptosis in lead-exposed workers

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Dorado, Itzel-Citlalli [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Hernández, Gerardo [Section of Methodology of Science, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Quintanar-Escorza, Martha-Angelica [Faculty of Medicine, UJED, Durango, DGO (Mexico); Maldonado-Vega, María [CIATEC, León, GTO (Mexico); Rosas-Flores, Margarita [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Calderón-Salinas, José-Víctor, E-mail: jcalder@cinvestav.mx [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico)

    2014-12-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca{sup 2+}]{sub i} and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca{sup 2+}], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers

  4. Eliminating Childhood Lead Poisoning: A Federal Strategy Targeting Lead Paint Hazards.

    Science.gov (United States)

    2000

    Noting that lead poisoning is a preventable disease, this report details a coordinated federal program to eliminate childhood lead poisoning in the United States. The report describes how lead poisoning harms children, how pervasive lead poisoning is, and how lead paint hazards in housing could be eliminated in 10 years. Following information on…

  5. Delayed visual maturation and lead pollution.

    Science.gov (United States)

    Gulson, B L; Yui, L A; Howarth, D

    1998-12-11

    Three children were born in the Broken Hill Australia lead mining community with delayed visual maturation of the optic nerve (blindness) within a period of 19 months. Because of the association with the lead pollution, the delayed visual maturation was attributed to lead exposure of the fetus during pregnancy. Lead isotopic analyses of the shed deciduous teeth from the three children demonstrate that they were not exposed to increased levels of lead from a mining or any other source during pregnancy and the etiology of the delayed visual maturation must be sought elsewhere.

  6. Occupational lead exposure and renin release.

    Science.gov (United States)

    Campbell, B C; Beattie, A D; Elliott, H L; Goldberg, A; Moore, M R; Beevers, D G; Tree, M

    1979-01-01

    Hypertension may result from chronic lead exposure. Lead poisoning arising from "moonshine whiskey" drinking has been associated with a rise in plasma renin activity. In the present study, plasma renin concentration following intravenous administration of frusemide was measured in eleven subjects with moderate or severe lead poisoning of industrial origin. The results were compared with those obtained for seven normal, control subjects. There was no significant difference in response obtained in the two groups. Industrial lead poisoning does not appear to affect renin release. The combined insult of lead and alcohol may explain the findings in the previous study.

  7. Percutaneous extraction of stented device leads.

    Science.gov (United States)

    Baranowski, Bryan; Wazni, Oussama; Chung, Roy; Martin, David O; Rickard, John; Tanaka-Esposito, Christine; Bassiouny, Mohammed; Wilkoff, Bruce L

    2012-05-01

    There are limited published data regarding the percutaneous extraction of device leads jailed by a venous stent. In this study we assessed the feasibility and safety of percutaneous extraction of stented device leads. We reviewed our experience percutaneously extracting 7 chronically implanted device leads jailed to the wall of the left innominate and/or subclavian veins by a previously placed stent. All leads were successfully extracted by using a percutaneous approach. Both pacing leads and defibrillator leads were extracted. The oldest pacing lead extracted was 14 years old. The oldest defibrillator lead extracted was 6 years old. Three of the leads were extracted with simple manual traction alone. The 4 remaining leads required a more complex, femoral extraction approach for successful removal. In our experience extracting 7 stented device leads, complete percutaneous removal was feasible 100% of the time using a combination of simple manual traction and a femoral approach. No major complications were associated with the extraction procedures. Copyright © 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  8. Validation of defibrillator lead performance registry data

    DEFF Research Database (Denmark)

    Kristensen, Anders Elgaard; Larsen, Jacob Moesgaard; Nielsen, Jens Cosedis

    2017-01-01

    AIMS: The validity of registry data on defibrillator lead performance is described only sparsely, despite its clinical importance. This study investigated the validity of defibrillator lead performance registry data in a nationwide and population-based registry. METHODS AND RESULTS: We identified.......9% (95% CI: 85.2-90.2%) with a κ value of 0.82 (95% CI:0.78-0.86) representing an almost perfect match. CONCLUSION: The validity of data on defibrillator lead performance recorded in the DPIR is excellent for the specific types of lead intervention and good for the specific reasons for defibrillator lead...... intervention. The validity of the less detailed overall reasons for lead interventions commonly used to report lead performance is also excellent. These findings indicate high registry data quality appropriate for scientific analysis and industry-independent post-marketing surveillance....

  9. Lead sources in human diet in Greenland

    DEFF Research Database (Denmark)

    Bjerregaard, Peter; Johansen, Poul; Mulvad, Gert

    2004-01-01

    Although blood lead levels have declined in Greenland, they are still elevated despite the fact that lead levels in the Greenland environment are very low. Fragments of lead shot in game birds have been suggested as an important source of dietary exposure, and meals of sea birds, particularly eider......, contain high concentrations of lead. In a cross-sectional population survey in Greenland in 1993-1994, blood lead adjusted for age and sex was found to be associated with the reported consumption of sea birds. Participants reporting less than weekly intake of sea birds had blood lead concentrations...... of approximately 75 microg/L, whereas those who reported eating sea birds several times a week had concentrations of approximately 110 microg/L, and those who reported daily intake had concentrations of 170 microg/L (p = 0.01). Blood lead was not associated with dietary exposure to other local or imported food...

  10. Lead intoxication in Sydney Harbour Bridge workers.

    Science.gov (United States)

    Pollock, C A; Ibels, L S

    1988-02-01

    Thirty-eight Sydney Harbour Bridge workers were assessed for possible lead intoxication. Forty-seven per cent were found to have significant lead intoxication as assessed by calcium disodium edetate chelation (Ca EDTA) testing and were subsequently effectively and safely treated with Ca EDTA. The prevalence of neurological, constitutional, gastrointestinal and musculoskeletal symptoms was significantly greater in those with, than those without, lead toxicity. Although blood lead levels and, to a lesser extent, hematological parameters were of some use in diagnosis, they were not sufficiently sensitive and thus should not be used in screening workers at risk of lead intoxication. Ca EDTA testing remains the diagnostic method of choice. Patients exposed to lead dust and fumes, in whom symptoms of lead intoxication are present, should undergo such testing and if a positive result is obtained, then EDTA chelation therapy should be instituted.

  11. How lead loses its toxicity to plants

    Directory of Open Access Journals (Sweden)

    Małgorzata Wierzbicka

    2014-01-01

    Full Text Available This paper is a brief review of the problem of lead-in the environment, particularly constitutional tolerance to lead about which little is known. Taking Allium cepa L. roots as a model it has been shown that after an initial phase in which lead is toxic to cells, defence processes appear with the results that lead is no longer poisonous. The lead which penetrates into the root symplast is detoxified in vacuoles, cell walls and dictiosomal vesicles. Initial cells of the meristem (quescent centre which play a basic role in the root regeneration processes are protected against lead penetration. This surprising result is in agreement with the absence of any symptoms of lead poisoning in plants growing in natural conditions, and suggests that there is a defence mechanism specific only for plant cells.

  12. Experimental oral lead toxicity in young dogs

    Energy Technology Data Exchange (ETDEWEB)

    Stowe, H.D.; Goyer, R.A.; Krigman, M.M.; Wilson, M.; Cates, M.

    1973-02-01

    Litter-mate male pups were fed a calcium-and-phosphorus-low purified diet with and without 100 ppm of lead as lead acetate from age 6 to 18 weeks. Lead-toxic dogs exhibited cyclic but terminally severe anorexia and cachexia, significant anemia, normoblastocytosis and leukopenia within six weeks, hypoproteinemia, decreased serum albumin, ..cap alpha../sub 1/-globulin, ..beta../sub 2/-globulin, alkaline phosphatase and lactic dehydrogenase 1, elevated serum glutamic oxaloacetic and pyruvic transaminases, delayed closure of the thoracic vertebral epiphyses, lead lines in the distal radii and thoracic spinous processes, enlargement of liver, kidney, and brain, hepatic fatty metamorphosis, focal proximal renal tubular necrosis, hydropic degeneration of spermatognia, and lead inclusion body formation. Approximately 97% of the tissue lead was estimated to be skeletal; the greatest concentration of lead in the brain was found in the occipital gray matter.

  13. 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.

  14. Association of Lead Levels and Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Neha Bansal MD

    2017-03-01

    Full Text Available Background: Cerebral palsy is a common motor disability in childhood. Raised lead levels affect cognition. Children with cerebral palsy may have raised lead levels, further impairing their residual cognitive motor and behavioral abilities. Environmental exposure and abnormal eating habits may lead to increased lead levels. Aims and Objectives: To measure blood lead levels in children with cerebral palsy and compare them with healthy neurologically normal children. To correlate blood lead levels with environmental factors. Material and Methods: Design: Prospective case-control study. Setting: Tertiary care hospital. Participants: Cases comprised 34 children with cerebral palsy, and controls comprised 34 neurologically normal, age- and sex-matched children. Methods: Clinical and demographic details were recorded as per proforma. Detailed environmental history was recorded to know the source of exposure to lead. These children were investigated and treated as per protocol. Venous blood was collected in ethylenediaminetetraacetic acid vials for analysis of blood lead levels. Lead levels were estimated by Schimadzu Flame AA-6800 (atomic absorption spectrophotometer. Data were analyzed using SPSS version 17. P < .05 was taken as significant. Results: Mean blood lead levels were 9.20 ± 8.31 µg/dL in cerebral palsy cases and 2.89 ± 3.04 µg/dL in their controls (P < .001. Among children with cerebral palsy, 19 (55.88% children had blood lead levels ≥5 µg/dL. Lead levels in children with pica were 12.33 ± 10.02 µg/dL in comparison to children with no history of pica, 6.70 ± 4.60 µg/dL (P = .029. No correlation was found between hemoglobin and blood lead levels in cases and controls. Conclusion: In our study, blood lead levels are raised in children with cerebral palsy. However, further studies are required to show effects of raised levels in these children.

  15. Get the Lead Out: Facts about Childhood Lead Poisoning [and] Housekeeping Tips To Reduce Lead Exposure [and] Nutrition and Lead Poisoning [and] The Medical Consequences of Lead Poisoning [and] Lead Poisoning for Health Care Providers.

    Science.gov (United States)

    Illinois State Dept. of Public Health, Springfield.

    This document is comprised of five fact sheets from the Illinois Department of Public Health regarding childhood lead poisoning. Recent studies claim that childhood lead poisoning can contribute to problems later in life, such as academic failure, juvenile delinquency, and high blood pressure. Directed to parents, caregivers, and health care…

  16. Vagus nerve stimulation after lead revision.

    Science.gov (United States)

    Dlouhy, Brian J; Viljoen, Steven V; Kung, David K; Vogel, Timothy W; Granner, Mark A; Howard, Matthew A; Kawasaki, Hiroto

    2012-03-01

    Vagus nerve stimulation (VNS) has demonstrated benefit in patients with medically intractable partial epilepsy. As in other therapies with mechanical devices, hardware failure occurs, most notably within the VNS lead, requiring replacement. However, the spiral-designed lead electrodes wrapped around the vagus nerve are often encased in dense scar tissue hampering dissection and removal. The objective in this study was to characterize VNS lead failure and lead revision surgery and to examine VNS efficacy after placement of a new electrode on the previously used segment of vagus nerve. The authors reviewed all VNS lead revisions performed between October 2001 and August 2011 at the University of Iowa Hospitals and Clinics. Twenty-four patients underwent 25 lead revisions. In all cases, the helical electrodes were removed, and a new lead was placed on the previously used segment of vagus nerve. All inpatient and outpatient records of the 25 lead revisions were retrospectively reviewed. Four cases were second lead revisions, and 21 cases were first lead revisions. The average time to any revision was 5 years (range 1.8-11.1 years), with essentially no difference between a first and second lead revision. The most common reason for a revision was intrinsic lead failure resulting in high impedance (64%), and the most common symptom was increased seizure frequency (72%). The average duration of surgery for the initial implantation in the 15 patients whose VNS system was initially implanted at the authors' institution was much shorter (94 minutes) than the average duration of lead revision surgery (173 minutes). However, there was a significant trend toward shorter surgical times as more revision surgeries were performed. Sixteen of the 25 cases of lead revision were followed up for more than 3 months. In 15 of these 16 cases, the revision was as effective as the previous VNS lead. In most of these cases, both the severity and frequency of seizures were decreased to levels

  17. Exposure to lead from intake of coffee

    DEFF Research Database (Denmark)

    Hansen, Max; Sloth, Jens Jørgen; Rasmussen, Rie Romme

    Food and beverages is one of the primary sources of intake of and exposure to lead, with beverages accounting for almost 50%. Previous studies from Denmark have estimated that the intake of lead from coffee is very high and may contribute to up to 20% of the total lead intake from food and bevera......Food and beverages is one of the primary sources of intake of and exposure to lead, with beverages accounting for almost 50%. Previous studies from Denmark have estimated that the intake of lead from coffee is very high and may contribute to up to 20% of the total lead intake from food...... and beverages. This estimate is, however, based on older, non-published data. In the current project extensive chemical analyses of coffee beans, drinking water and ready-to-drink coffee have been performed. The results hereof have been compared to calculations of the total intake of lead from food...... and beverages. The results show that the intake of lead from coffee is considerably lower than previously estimated and account for 4.2% and 3.3% of the total lead intake from food and beverages for Danish men and women, respectively. It can generally be concluded that the intake of lead from coffee is low...

  18. Lead contamination of paint remediation workers' vehicles.

    Science.gov (United States)

    Boraiko, Carol; Wright, Eva M; Ralston, Faye

    2013-03-01

    Exposure to lead has been shown to be harmful to adults; it is a teratogen, it can damage the peripheral nervous system, and it adversely affects the reproductive system. Professional lead-based paint remediation workers are at risk of exposure to lead dust. The authors' study was conducted to determine if these remediation workers transfer lead from their work site to their vehicles and then potentially expose their families. It was hypothesized that remediation workers transported the lead from the remediation work site to the floorboards of their vehicles due to not following required protective equipment use. The laboratory's level of quantitation for lead on the wipe samples, 10 microg/ft2, was used to indicate lead contamination. This level was exceeded in 50% of the floorboards sampled. These results confirm that many vehicle floorboards used by remediation workers are contaminated with lead dust, potentially resulting in transfer of lead dust. The ultimate detrimental outcome could be the transfer of lead particles to other family members, causing the poisoning of a child or other at-risk person.

  19. Hypogonadism in chronically lead-poisoned men.

    Science.gov (United States)

    Braunstein, G D; Dahlgren, J; Loriaux, D L

    1978-01-01

    The hypothalamic-pituitary-testicular axis was evaluated in 10 men with occupational lead exposure, 9 of whom had noted a decrease in libido and frequency of intercourse following this exposure. 6 of these men had clinically apparent lead poisoning while 4 were classified as being only lead-exposed. Results of the endocrine evaluation of these patients were compared to those obtained on 9 age and socioeconomically matched control patients. Both lead poisoned and lead-exposed patients had reduced basal serum testosterone levels and normal basal serum testosterone-estradiol-binding globulin capacity, estradiol, LH, FSH, and prolactin levels. Both groups demonstrated an appropriate rise in serum testosterone following hCG stimulation and a normal increment in serum FSH in response to clomiphene citrate and gonadotropin-releasing hormone in comparison to the control group. The lead poisoned patients demonstrated a significantly reduced increment in serum LH after clomiphene citrate and gonadotropin-releasing hormone administration while the lead-exposed patients had normal LH dynamics. Testicular biopsies carried out on the 2 most severely lead-poisoned men showed peritubular fibrosis, oligospermia, and vacuolization of the Sertoli cells. These results suggest that lead poisoning may lead to a pituitary-hypothalamic defect in LH secretion and may also result in direct testicular seminiferous tubular injury.

  20. Lead in food and food containers

    Energy Technology Data Exchange (ETDEWEB)

    Chu, A.O. [Univ. of California, Berkeley, CA (United States)

    1994-04-01

    We investigated food and food containers suspected of containing high levels of lead. Food containers investigated were bought in Northern California and were linked to several cases of lead poisoning in children and adults. Coffee mugs and Mexican pottery were leached with acetic and citric acid, respectively. The amount of lead leached from the lip and rim area of eleven coffee mugs ranged from non detectable to 79 ppm. Lead leached from Mexican potteries ranged from non detectable to 584 ppm of lead. Although there are no regulations pertaining to the amount of lead in the lip and rim area of ceramic ware, under California proposition 65 vendors are required to warn consumers of the presence of toxic materials in consumer products. Foods analyzed for lead content were candy and beans. A sample of tamarindo candy taken from the center of its storage container, a mexican clay pot, was found to contain 1.0 ppm of lead, while the candy in contact with the glaze contained 16 ppm of lead. Beans cooked in Mexican clay cooking pots contained lead ranging from 2.8 to 9.2 ppm. Two-thirds of the food containers investigated and the food analyzed did not meet the provisional Total Tolerable Daily Intake level let by the U.S. FDA, assuming a reasonable amount of liquid and food was ingested.

  1. Association of Lead Levels and Cerebral Palsy.

    Science.gov (United States)

    Bansal, Neha; Aggarwal, Anju; Faridi, M M A; Sharma, Tusha; Baneerjee, B D

    2017-01-01

    Background: Cerebral palsy is a common motor disability in childhood. Raised lead levels affect cognition. Children with cerebral palsy may have raised lead levels, further impairing their residual cognitive motor and behavioral abilities. Environmental exposure and abnormal eating habits may lead to increased lead levels. Aims and Objectives: To measure blood lead levels in children with cerebral palsy and compare them with healthy neurologically normal children. To correlate blood lead levels with environmental factors. Material and Methods:Design: Prospective case-control study. Setting: Tertiary care hospital. Participants: Cases comprised 34 children with cerebral palsy, and controls comprised 34 neurologically normal, age- and sex-matched children. Methods: Clinical and demographic details were recorded as per proforma. Detailed environmental history was recorded to know the source of exposure to lead. These children were investigated and treated as per protocol. Venous blood was collected in ethylenediaminetetraacetic acid vials for analysis of blood lead levels. Lead levels were estimated by Schimadzu Flame AA-6800 (atomic absorption spectrophotometer). Data were analyzed using SPSS version 17. P cerebral palsy cases and 2.89 ± 3.04 µg/dL in their controls (P cerebral palsy, 19 (55.88%) children had blood lead levels ≥5 µg/dL. Lead levels in children with pica were 12.33 ± 10.02 µg/dL in comparison to children with no history of pica, 6.70 ± 4.60 µg/dL (P = .029). No correlation was found between hemoglobin and blood lead levels in cases and controls. Conclusion: In our study, blood lead levels are raised in children with cerebral palsy. However, further studies are required to show effects of raised levels in these children.

  2. 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

  3. The refining of secondary lead for use in advanced lead-acid batteries

    Science.gov (United States)

    Ellis, Timothy W.; Mirza, Abbas H.

    Secondary lead, i.e. material produced by the recycling of lead-acid batteries has become the primary source of lead in much of the world. This has been important to the secondary lead industry as other uses have dwindled, e.g. lead based pigments, chemicals, fuel additives, solders and CRT glasses [1]. Presently, battery manufacturing accounts for greater than 80% of lead consumption while recycled lead accounts for approximately the same market share of lead supply. These two facts strongly demonstrate the battery manufacturing and recycled lead are intimately coupled in everyday life. In this paper we will explore how recycled lead has become the material of choice for battery construction through the development of a recovery and refining process that exceeds the industries requirements. Particular focus will be on addressing the results presented by Prengaman [2] on the effects of contaminant or tramp elements on gassing in lead-acid batteries.

  4. Lead Poisoning Due to Herbal Medications.

    Science.gov (United States)

    Chambial, Shailja; Bhardwaj, Pankaj; Mahdi, Abbas Ali; Sharma, Praveen

    2017-06-01

    Lead ranks as one of the most serious environmental poisons all over the world amongst toxic heavy metals with no known biological function useful for the human body. A case of lead toxicity due to consumption of herbal medicine is being discussed. The case presented with gastrointestinal complaints and history of intake of herbal medicines for diabetes control for past 8 months. The analysis of the powdered herbal medicine procured from ayurveda practitioner was found to have high content of lead responsible for the lead toxicity. The patient is under regular followup. He has improved symptomatically on chelating therapy and blood lead levels have gradually improved. Regular awareness programs should be conducted in the population regarding possible exposure through home made herbal remedies so that general public can be made aware of the dangerous side effects of lead and other heavy metals on health.

  5. Innovation Management, Lead Users and Social Media

    DEFF Research Database (Denmark)

    Ernst, M.; Brem, Alexander; Voigt, K.-I.

    2013-01-01

    to integrate external knowledge into innovation processes. This approach is discussed by considering the integration of customers and especially Lead-Users into corporate product development. Based on the concept of Open Innovation, we reflect the role of Lead-Users in the innovation process critically....... Mounting on our reflections, we show the potentials of social media for integrating Lead-Users and develop a conceptual framework for the integration of Lead-Users using different social media applications. Findings — In this paper, a conceptual framework for integrating Lead-Users by using different...... social media applications is developed and introduced. Originality/value — The unique conceptual framework derived in this chapter is enriched with a discussion of the challenges resulting from the implementation of Lead-User integration along with social media in corporate innovation management...

  6. Apparatus and methods for purifying lead

    Science.gov (United States)

    Tunison, Harmon M.

    2016-01-12

    Disclosed is an exemplary method of purifying lead which includes the steps of placing lead and a fluoride salt blend in a container; forming a first fluid of molten lead at a first temperature; forming a second fluid of the molten fluoride salt blend at a second temperature higher than the first temperature; mixing the first fluid and the second fluid together; separating the two fluids; solidifying the molten fluoride salt blend at a temperature above a melting point of the lead; and removing the molten lead from the container. In certain exemplary methods the molten lead is removed from the container by decanting. In still other exemplary methods the molten salt blend is a Lewis base fluoride eutectic salt blend, and in yet other exemplary methods the molten salt blend contains sodium fluoride, lithium fluoride, and potassium fluoride.

  7. Extraction of superfluous device leads: A comparison with removal of infected leads.

    Science.gov (United States)

    Huang, Xin-Miao; Fu, Haixia; Osborn, Michael J; Asirvatham, Samuel J; McLeod, Christopher J; Glickson, Michael; Acker, Nancy G; Friedman, Paul A; Cha, Yong-Mei

    2015-06-01

    Although increasingly more lead extraction was performed for superfluous leads, the extraction of such leads remains controversial. The objective of this study was to determine the outcomes and complications of transvenous extraction of superfluous leads in a single center in the era of laser technology. Four hundred eighty transvenous lead extraction procedures performed from January 2001 through October 2012 at Mayo Clinic (Rochester, Minnesota) were retrospectively reviewed. Of these, 123 procedures were performed for superfluous functional or nonfunctional leads. Data were collected from electronic medical records and an institutional database of cardiovascular implantable electronic devices. A total of 167 superfluous leads (mean [SD] lead duration 53 [53] months; median 34 months) were removed during the 123 procedures. Forty-one percent of procedures were for lead malfunction. The procedural complete-success rate was 96.7%. Major complications occurred in 1 patient (0.8%), who had a superior vena cava tear that required thoracotomy. Superfluous leads had been implanted for a shorter period of time than infected leads (mean [SD] 53 [53] vs 81 [59] months; P leads than for leads associated with infection (97% vs 92%; P = .05). Transvenous extraction of superfluous leads is highly successful, with few procedural complications. Extraction of superfluous leads at the time of device upgrade or lead revision is considered reasonable to avoid the increasing risk of extraction complications with lead aging. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  8. Lead in tissues of mallard ducks dosed with two types of lead shot

    Science.gov (United States)

    Finley, M.T.; Dieter, M.P.; Locke, L.N.

    1976-01-01

    Mallard ducks (Anas platyrhynchos) were sacrificed one month after ingesting one number 4 all-lead shot or one number 4 lead-iron shot. Livers, kidneys, blood, wingbones, and eggs were analyzed for lead by atomic absorption. Necropsy of sacrificed ducks failed to reveal any of the tissue lesions usually associated with lead poisoning in waterfowl. Lead levels in ducks given all-lead shot averaged about twice those in ducks given lead-iron shot, reflecting the amount of lead in the two types of shot. Lead in the blood of ducks dosed with all-lead shot averaged 0.64 ppm, and 0.28 ppm in ducks given lead-iron shot. Lead residues in livers and kidneys of females given all-lead shot were significantly higher than in males. In both dosed groups, lead levels in wingbones of females were about 10 times those in males, and were significantly correlated with the number of eggs laid after dosage. Lead levels in contents and shells of eggs laid by hens dosed with all-lead shot were about twice those in eggs laid by hens dosed with lead-iron shot. Eggshells were found to best reflect levels of lead in the blood. Our results indicate that mallards maintained on a balanced diet and dosed with one lead shot may not accumulate extremely high lead levels in the liver and kidney. However, extremely high lead deposition may result in the bone of laying hens after ingesting sublethal amounts of lead shot as a result of mobilization of calcium from the bone during eggshell formation.

  9. NASA DOD Lead Free Electronics Project

    Science.gov (United States)

    Kessel, Kurt R.

    2008-01-01

    The primary'technical objective of this project is to undertake comprehensive testing to generate information on failure modes/criteria to better understand the reliability of: Packages (e.g., Thin Small Outline Package [TSOP], Ball Grid Array [BGA], Plastic Dual In-line Package [PDIPD assembled and reworked with lead-free alloys Packages (e.g., TSOP, BGA, PDIP) assembled and reworked with mixed (lead/lead-free) alloys.

  10. Lead in ancient Rome's city waters

    OpenAIRE

    Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe; Keay, Simon; Albarède, Francis

    2014-01-01

    International audience; It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Mid...

  11. PRODUCTION OF LEAD-FREE SOLDER POWDERS

    OpenAIRE

    Mustafacan , Kutsal

    2014-01-01

    The intentional use of conventional tin-lead (Sn-Pb) solder alloys was restricted with legislations across the world due to the toxic nature and the adverse effects of lead on health and the environment. Consequently, the development of new lead-free solder alloys has become a significant area of research. In addition to these health concerns, the continuing miniaturization trend of the consumer electronics has been pushing the production of solders from bulk form to powder form. In this stud...

  12. Healthy People 2020: Leading Health Indicators

    Science.gov (United States)

    ... Maternal, Infant, and Child Health Mental Health Nutrition, Physical Activity, and Obesity Oral Health Reproductive and Sexual Health Social Determinants Substance Abuse Tobacco Leading Health Indicators Healthy ...

  13. Toxicity of dietary lead in young cockerels.

    Science.gov (United States)

    Franson, J C; Custer, T W

    1982-12-01

    Day-old cockerels received 1850 ppm dietary lead for 4 wks. Blood delta-aminolevulinic acid dehydratase (ALAD) activity was reduced to 1.6% of control activity by the end of the study. Hemoglobin concentration (Hb) in lead-exposed cockerels was significantly less than that of controls at 7, 14, and 28 days, and packed cell volume (PCV) was significantly reduced at 14 days. Blood lead residues reached 832 micrograms/dl in exposed cockerels; kidney residues were about three times liver residues. At the termination of the study mean body weight of lead-exposed birds was 47% of controls.

  14. Testing of sealed lead-acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    Bush, D.M.; Sealey, J.D.; Miller, D.W.

    1984-02-01

    In early January 1981, Sandia National Laboratories began testing sealed lead-acid batteries which were being developed under Sandia contracts. The goal was to develop a totally maintenance-free sealed lead-acid battery capable of deep-discharge operation in a photovoltaic power system. Sealed lead-acid batteries and a group of conventional, flooded lead-acid batteries were exposed to a matrix test plan, with some approaching 1000 cycles. This performance was achieved with the standard National Electrical Manufacturers' Association cycle test, as well as the partial-state-of-charge cycle test. Modes of failure are being investigated.

  15. Lead in wild blackberries from suburban roadsides

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J.G.

    1979-01-01

    A mean lead content of 0.79 mg kg/sup -1/ was found for wild blackberries from roadside hedgerows in a suburban area of Glasgow. This represents a five-fold enhancement in lead content relative to blackberries from non-roadside environments and can be attributed to the emission of lead-containing compounds from car exhaust. Washing typically removed less than or equal to 0.1 mg kg/sup -1/. However, M.A.F.F. (1975) recommended limits for lead in fresh food (1 mg kg/sup -1/) and canned fruits and preserves (2 mg kg/sup -1/) were not, in general, exceeded.

  16. 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...

  17. Lead poisoning in woodpeckers in Sweden.

    Science.gov (United States)

    Mörner, T; Petersson, L

    1999-10-01

    Lead poisoning was demonstrated in two gray-headed woodpeckers (Picus canus) and one white-backed woodpecker (Dendrocopus leucotos) in Sweden; they had liver lead levels between 9.4 and 26.2 mg(-1) wet weight. At necropsy one gray-headed woodpecker showed signs of emaciation and the other one had severe traumatic injuries, caused by a cat. The white-backed woodpecker died in the transportation box during a translocation program. The source of the lead could not be determined, but it was suspected that it may have originated from lead pellets shot into trees and picked out by the woodpeckers during food search.

  18. Can deunionization lead to international outsourcing?

    National Research Council Canada - National Science Library

    Lommerud, Kjell Erik; Meland, Frode; Straume, Odd Rune

    2009-01-01

    .... Such outsourcing leads to increased wages for the remaining in-house production. We find that stronger unions, which imply higher domestic wages, reduce incentives for international outsourcing...

  19. Learning Media Programme, leads for innovation

    NARCIS (Netherlands)

    Westera, Wim

    2010-01-01

    Westera, W. (2010, 25 January). Learning Media Programme, leads for innovation. Presentation for Deans of Open University of the Netherlands, Heerlen, The Netherlands: Open University of the Netherlands.

  20. 76 FR 12944 - Children's Products Containing Lead; Technological Feasibility of 100 ppm for Lead Content...

    Science.gov (United States)

    2011-03-09

    ... COMMISSION Children's Products Containing Lead; Technological Feasibility of 100 ppm for Lead Content; Notice... feasibility of meeting the 100 ppm lead content limit for children's products and associated public health... laboratories regarding the technological feasibility of meeting the 100 ppm lead content limit. At the hearing...

  1. 76 FR 44463 - Children's Products Containing Lead; Technological Feasibility of 100 ppm for Lead Content...

    Science.gov (United States)

    2011-07-26

    ... Lead Content; Notice of Effective Date of 100 ppm Lead Content Limit in Children's Products AGENCY: U.S... technological feasibility of meeting the 100 ppm lead content limit for children's products and associated... statutory 100 ppm lead content limit on August 14, 2011, unless otherwise excluded under CPSC regulations.\\1...

  2. The relationship between environmental lead and blood lead in children : a study in environmental epidemiology

    NARCIS (Netherlands)

    Brunekreef, B.

    1985-01-01

    This study deals with the relationship between environmental lead and blood lead in children.
    Chapter 1 provides a summary of the environmental health aspects of lead. The occurrence of lead in the environment and in man is described; children are discussed as a population at

  3. Evaluation of the use of salivary lead levels as a surrogate of blood lead or plasma lead levels in lead exposed subjects

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Fernando [Universidade de Sao Paulo, Departamento de Analises Clinicas, Toxicologicas e Bromatologicas, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto, Ribeirao Preto, SP (Brazil); Correa Rodrigues, Maria H.; Buzalaf, Maria R. [Universidade de Sao Paulo, Departamento de Ciencias Biologicas/Bioquimica, Faculdade de Odontologia de Bauru, Bauru, SP (Brazil); Krug, Francisco J. [Universidade de Sao Paulo, Centro de Energia Nuclear na Agricultura, Piracicaba, SP (Brazil); Gerlach, Raquel F. [Universidade de Sao Paulo, Departamento de Morfologia, Estomatologia e Fisiologia, Faculdade de Odontologia de Ribeirao Preto, Ribeirao Preto, SP (Brazil); Tanus-Santos, Jose E. [Universidade de Sao Paulo, Departamento de Farmacologia, Faculdade de Medicina de Ribeirao Preto, Ribeirao Preto, SP (Brazil)

    2006-10-15

    We conducted a study to evaluate the use of parotid salivary lead (Pb-saliva) levels as a surrogate of the blood lead (Pb-B) or plasma lead levels (Pb-P) to diagnose lead exposure. The relationship between these biomarkers was assessed in a lead exposed population. Pb-saliva and Pb-P were determined by inductively coupled plasma mass spectrometry, while in whole blood lead was determined by graphite furnace atomic absorption spectrometry. We studied 88 adults (31 men and 57 women) from 18 to 60 years old. Pb-saliva levels varied from 0.05 to 4.4 {mu}g/l, with a mean of 0.85 {mu}g/l. Blood lead levels varied from 32.0 to 428.0 {mu}g/l in men (mean 112.3 {mu}g/l) and from 25.0 to 263.0 {mu}g/l (mean 63.5 {mu}g/l) in women. Corresponding Pb-Ps were 0.02-2.50 {mu}g/l (mean 0.77 {mu}g/l) and 0.03-1.6 {mu}g/l (mean 0.42 {mu}g/l) in men and women, respectively. A weak correlation was found between Log Pb-saliva and Log Pb-B (r=0.277, P<0.008), and between Log Pb-saliva and Log Pb-P (r=0.280, P=0.006). The Pb-saliva/Pb-P ratio ranged from 0.20 to 18.0. Age or gender does not affect Pb-saliva levels or Pb-saliva/Pb-P ratio. Taken together, these results suggest that salivary lead may not be used as a biomarker to diagnose lead exposure nor as a surrogate of plasma lead levels at least for low to moderately lead exposed population. (orig.)

  4. Measurement Challenges at Low Blood Lead Levels.

    Science.gov (United States)

    Caldwell, Kathleen L; Cheng, Po-Yung; Jarrett, Jeffery M; Makhmudov, Amir; Vance, Kathryn; Ward, Cynthia D; Jones, Robert L; Mortensen, Mary E

    2017-08-01

    In 2012, the Centers for Disease Control and Prevention (CDC) adopted its Advisory Committee on Childhood Lead Poisoning Prevention recommendation to use a population-based reference value to identify children and environments associated with lead hazards. The current reference value of 5 μg/dL is calculated as the 97.5th percentile of the distribution of blood lead levels (BLLs) in children 1 to 5 years old from 2007 to 2010 NHANES data. We calculated and updated selected percentiles, including the 97.5th percentile, by using NHANES 2011 to 2014 blood lead data and examined demographic characteristics of children whose blood lead was ≥90th percentile value. The 97.5th percentile BLL of 3.48 µg/dL highlighted analytical laboratory and clinical interpretation challenges of blood lead measurements ≤5 μg/dL. Review of 5 years of results for target blood lead values Lead and Multi-Element Proficiency quality assurance program showed 40% unable to quantify and reported a nondetectable result at a target blood lead value of 1.48 µg/dL, compared with 5.5% at a target BLL of 4.60 µg/dL. We describe actions taken at the CDC's Environmental Health Laboratory in the National Center for Environmental Health, which measures blood lead for NHANES, to improve analytical accuracy and precision and to reduce external lead contamination during blood collection and analysis. Copyright © 2017 by the American Academy of Pediatrics.

  5. Lead: Aspects of its ecology and environmental toxicity. [physiological effects of lead compound contamination of environment

    Science.gov (United States)

    Siegel, S. M.

    1973-01-01

    An analysis of lead toxicity in the Hawaiian environment was conducted. It was determined that lead enters the environment as an industrial contaminant resulting from the combustion of leaded gasoline. The amount of lead absorbed by the plants in various parts of the Hawaiian Islands is reported. The disposition of lead in the sediments of canals and yacht basins was investigated. The methods for conducting the surveys of lead content are described. Possible consequences of continued environmental pollution by burning leaded gasoline are discussed.

  6. Effect of Breast Milk Lead on Infant Blood Lead Levels at 1 Month of Age

    OpenAIRE

    Téllez-Rojo, Martha María; Hu, Howard; Hernández-Avila, Mauricio; Ettinger, Adrienne S.; Amarasiriwardena, Chitra J.; Bellinger, David C.; Peterson, Karen E.; Schwartz, Joel David

    2004-01-01

    Nursing infants may be exposed to lead from breast milk, but relatively few data exist with which to evaluate and quantify this relationship. This route of exposure constitutes a potential infant hazard from mothers with current ongoing exposure to lead as well as from mothers who have been exposed previously due to the redistribution of cumulative maternal bone lead stores. We studied the relationship between maternal breast milk lead and infant blood lead levels among 255 mother?infant pair...

  7. The energy efficiency of lead selfsputtering

    DEFF Research Database (Denmark)

    Andersen, Hans Henrik

    1968-01-01

    The sputtering efficiency (i.e. ratio between sputtered energy and impinging ion energy) has been measured for 30–75‐keV lead ions impinging on polycrystalline lead. The results are in good agreement with recent theoretical estimates. © 1968 The American Institute of Physics...

  8. Leading Learning: Science Departments and the Chair

    Science.gov (United States)

    Melville, Wayne; Campbell, Todd; Jones, Doug

    2016-01-01

    In this article, we have considered the role of the chair in leading the learning necessary for a department to become effective in the teaching and learning of science from a reformed perspective. We conceptualize the phrase "leading learning" to mean the chair's constitution of influence, power, and authority to intentionally impact…

  9. STABILIZATION OF LEAD-BASED PAINT WASTE

    Science.gov (United States)

    This study evaluated the ability of a cementitious stabilizing agent to reduce leachable lead from lead-based paint waste removed from substrate via blasting, and to evaluate the mechanism by which the reduction occurs. Testing demonstrated that the representative cementitious ag...

  10. Snapshots from a leading eco-city

    DEFF Research Database (Denmark)

    Mehlsen, Camilla

    2009-01-01

    The government of Singapore wants to make Singapore the leading Eco-city in Asia. Professor Kim Chuan Goh explains why this might be an achievable goal.......The government of Singapore wants to make Singapore the leading Eco-city in Asia. Professor Kim Chuan Goh explains why this might be an achievable goal....

  11. SHORT COMMUNICATION REMOVAL OF LEAD IONS FROM ...

    African Journals Online (AJOL)

    a

    ABSTRACT. A simple cost effective and eco-friendly method for the remediation of lead from industrial wastewater has been investigated. A novel biomaterial, Tridax procumbens (Asteraceae) a medicinal plant, was used for the removal of lead ions from synthetic wastewater and the method was also applied for real sample ...

  12. 29 CFR 1926.62 - Lead.

    Science.gov (United States)

    2010-07-01

    ... of paragraph (d)(10) of this section. (5) Negative initial determination. Where a determination... used to determine methods selected for controlling exposure to lead; (C) A report of the technology... potentially harmful effects of exposure to lead. (vii) The employer shall assure that the containers of...

  13. DROP AMALGAM VOLTAMMETRIC STUDY OF LEAD ...

    African Journals Online (AJOL)

    a

    ABSTRACT. A study of inorganic complexation of lead using drop amalgam voltammetry is described. The study has been carried out in simulated salt lake water and at ionic strength of. 7.35 M, the predetermined ionic strength of Lake Katwe. The complexation of lead with the simple ligands (Cl-, CO3. 2-) created anodic ...

  14. Leading edge gypsy moth population dynamics

    Science.gov (United States)

    M. R. Carter; F. W. Ravlin; M. L. McManus

    1991-01-01

    Leading edge gypsy moth populations have been the focus of several intervention programs (MDIPM, AIPM). Knowledge of gypsy moth population dynamics in leading edge area is crucial for effective management. Populations in these areas tend to reach outbreak levels (noticeable defoliation) within three to four years after egg masses are first detected. Pheromone traps...

  15. 29 CFR 1915.1025 - Lead.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Lead. 1915.1025 Section 1915.1025 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED... Lead. Note: The requirements applicable to shipyard employment under this section are identical to...

  16. Implantable Cardiac Defibrillator Lead Failure and Management.

    Science.gov (United States)

    Swerdlow, Charles D; Kalahasty, Gautham; Ellenbogen, Kenneth A

    2016-03-22

    The implantable-cardioverter defibrillator (ICD) lead is the most vulnerable component of the ICD system. Despite advanced engineering design, sophisticated manufacturing techniques, and extensive bench, pre-clinical, and clinical testing, lead failure (LF) remains the Achilles' heel of the ICD system. ICD LF has a broad range of adverse outcomes, ranging from intermittent inappropriate pacing to proarrhythmia leading to patient mortality. ICD LF is often considered in the context of design or construction defects, but is more appropriately considered in the context of the finite service life of a mechanical component placed in chemically stressful environment and subjected to continuous mechanical stresses. This clinical review summarizes LF mechanisms, assessment, and differential diagnosis of LF, including lead diagnostics, recent prominent lead recalls, and management of LF and functioning, but recalled leads. Despite recent advances in lead technology, physicians will likely continue to need to understand how to manage patients with transvenous ICD leads. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  17. [Children exposure to lead in contaminated sites].

    Science.gov (United States)

    Flores-Ramírez, Rogelio; Rico-Escobar, Edna; Núñez-Monreal, Jorge E; García-Nieto, Edelmira; Carrizales, Leticia; Ilizaliturri-Hernández, César; Díaz-Barriga, Fernando

    2012-01-01

    To assess the exposure to lead in children living in various types of contaminated sites. The study was conducted from June 2008 to December 2009 at four sites in Mexico: Avalos metallurgical, Chihuahua; Morales metallurgical, San Luis Potosí (SLP); Trinidad pottery area, Tlaxcala and Cedral mine site, SLP. These sites contain different sources of lead. The metal levels were quantified in outdoor dust and in peripheral blood of children. Lead dust concentrations exceed the National Guidelines for residential soils (400 mg/kg) in a range of values for the four sites from 62 to 5 187 mg/kg. Regarding biological monitoring, the studied children showed maximum lead blood levels of 22 µg/dL in Cedral, 31 µg/dL in Morales, 32 µg/dL in Avalos, and 52 µg/dL in Trinidad. It is important to mention that in all the studied sites, a significative positive correlation was found between blood lead levels and the lead concentrations in dust. These sites are an example of the health risks related to lead exposure in Mexico; therefore, there is an urgent need for a national public health program aimed at reducing lead exposure in vulnerable populations.

  18. SPECTROSCOPIC STUDIES AND THERMAL ANALYSIS OF LEAD ...

    African Journals Online (AJOL)

    a

    KEY WORDS: Lead, Tin, Schiff base, Infrared spectra, Thermal analysis. INTRODUCTION ... elemental analysis, infrared spectra as well as by their thermal analysis (DTA and TG). Analysis results are reported in Table 1. The percentage of lead and tin metals were determined using ..... PbO + 5C + 10C2H2 + N2 + CO.

  19. SQUARE WAVE VOLTAMMETRIC DETERMINATION OF LEAD IN ...

    African Journals Online (AJOL)

    2011-12-31

    Dec 31, 2011 ... ABSTRACT. A simple sensitive square wave voltammetric method for the determination of lead contamination of several kohl samples purchased from Algeria retail stores was developed using glassy carbon electrode. The peak current response of 5 standards aqueous solution of lead in NaNO3 as ...

  20. Indigenous tooth powders = covert lead poisoning?

    Science.gov (United States)

    Hegde, Sapna; Shubha, A B; Rao, B Dinesh

    2013-01-01

    The present study aimed to measure the concentration of lead in various indigenous preparations of tooth powders available and used locally in and around Udaipur, Rajasthan, India. Seven different brands of tooth powders manufactured and/or marketed locally were obtained from stores all over Udaipur city. Some home-made powders commonly used for cleaning teeth were also collected. The tooth powders were analyzed for lead content by atomic absorption spectrophotometry. All tooth powders tested were found to contain high levels of lead ranging from 21 ppm to 82 ppm, above the maximum permissible level of 20 ppm prescribed by the Bureau of Indian Standards. Indigenous tooth powders contain high levels of lead and thus may be a source of lead poisoning that is often overlooked.

  1. Exploring how lead users develop radical innovation

    DEFF Research Database (Denmark)

    Lettl, Christopher; Gemuenden, Hans Georg; Hienerth, C.

    2008-01-01

    In this study, we explore how lead users develop radical innovations outside of manufacturing firms. We analyze the transition from a very early stage of activities to the ultimate commercialization of these innovations. The focus in this context is on the initiatives undertaken by lead users...... in order to transform their radically new solutions into functional prototypes and then to convince established manufacturers of the technological and market potential of their innovations. Using a comparative case study design in the high-tech field of medical equipment technology, we find that individual...... lead users as surgeons launch entrepreneurial activities and bridge periods in which established medical equipment manufacturers would not risk investing in radical innovations. By doing so, lead users create the conditions usually provided in manufacturer-initiated lead user projects, including...

  2. Vector boson and Charmonium production in proton-lead and lead-lead collisions with ATLAS at the LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00241320; The ATLAS collaboration

    2016-01-01

    Electroweak bosons do not interact strongly with the dense and hot medium formed in nuclear collisions, and thus should be sensitive to the nuclear modification of parton distribution functions (nPDFs). The in-medium modification of heavy charmonium states plays an important role in studying the hot and dense medium. The ATLAS detector, optimized to search for new physics in proton-proton collisions, is well equipped to measure Z and W bosons as well as quarkonium in the high occupancy environment produced in heavy ion collisions. Results from the ATLAS experiment on W and Z boson yields as a function of centrality, transverse momentum and rapidity, in lead-lead and proton-lead collisions are presented. Quarkonium results from proton-lead collisions are also presented.

  3. Lead in new paints in Nepal.

    Science.gov (United States)

    Gottesfeld, Perry; Pokhrel, Dhiraj; Pokhrel, Amod K

    2014-07-01

    Samples from 75 paint products made by 21 domestic and foreign manufacturers were purchased from retail stores in five major cities in Nepal and tested for lead content. Information provided on product labels were noted. Samples were selected to be representative of the large number of brands and colors available in retail shops. Although a majority of the products purchased were manufactured in Nepal, paints from four additional countries were tested. Out of a total of 75 samples, 57 (76%) of the tested paints contained lead at concentrations greater than 90 ppm (ppm). Ninety-three percent of the paints that exceeded 90 ppm had levels in excess of 600 ppm. Lead concentrations in the tested paints ranged up to 200,000 ppm (20%) lead by weight and the median concentration was 5100 ppm. These results indicate that lead paint is commonly being sold for residential and other consumer applications in Nepal without any consumer warnings. Regulations are needed to specify the maximum concentration of lead allowed in paint products manufactured, imported, or distributed in the country to protect public health. Efforts must be made to get lead-containing paint products recalled from stores so that they are not used in homes, schools, and other child-occupied facilities. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Lead-acid batteries with foam grids

    Science.gov (United States)

    Tabaatabaai, S. M.; Rahmanifar, M. S.; Mousavi, S. A.; Shekofteh, S.; Khonsari, Jh.; Oweisi, A.; Hejabi, M.; Tabrizi, H.; Shirzadi, S.; Cheraghi, B.

    Conventional lead-acid batteries are relatively heavy and thus have a low specific energy. Therefore, to improve the energy density, a lighter grid has been proposed. In this work, a novel lead-acid battery with high specific surface area negative foam current collectors was designed and constructed. The collectors were studied by cyclic voltametery (CV) and electrochemical impedance spectroscopy (EIS). The foam collectors were designed and suitable paste composition and formation algorithm was obtained. The basic cells were manufactured and its performance was evaluated. The results showed that the foam grids resistance was lower than that for lead grids and the specific surface area of the foam grids was very greater than lead grids. The foam battery has good discharge characteristics compared with common lead-acid batteries. The discharge curve was flat and negative mass utilization efficiency was higher than 50% when the cell was discharged with C5/5 A (137 Ah kg -1 negative active materials). The foam grids were used as negative electrode for various types of lead-acid batteries such as 60 Ah starter battery, 2, 3 and 10 Ah VRLA batteries. The batteries with foam grids were shown longer cycle life than conventional lead-acid batteries.

  5. Lead poisoning and brain cell function

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, G.W. (Johns Hopkins School of Medicine, Baltimore, MD (USA) Kennedy Institute, Baltimore, MD (USA))

    1990-11-01

    Exposure to excessive amounts of inorganic lead during the toddler years may produce lasting adverse effects upon brain function. Maximal ingestion of lead occurs at an age when major changes are occurring in the density of brain synaptic connections. The developmental reorganization of synapses is, in part, mediated by protein kinases, and these enzymes are particularly sensitive to stimulation by lead. By inappropriately activating specific protein kinases, lead poisoning may disrupt the development of neural networks without producing overt pathological alterations. The blood-brain barrier is another potential vulnerable site for the neurotoxic action of lead. protein kinases appear to regulate the development of brain capillaries and the expression of the blood-brain barrier properties. Stimulation of protein kinase by lead may disrupt barrier development and alter the precise regulation of the neuronal environment that is required for normal brain function. Together, these findings suggest that the sensitivity of protein kinases to lead may in part underlie the brain dysfunction observed in children poisoned by this toxicant.

  6. Biological fractionation of lead isotopes in Sprague-Dawley rats lead poisoned via the respiratory tract.

    Science.gov (United States)

    Wu, Jing; Liu, Duojian; Xie, Qing; Wang, Jingyu

    2012-01-01

    It was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems. 24 male Sprague-Dawley (SD) rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate) via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces) were collected for comparison with the lead acetate (test substance) and the low-lead animal feed (diet) administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS). There are significant differences (pisotope ratios between blood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of (204)Pb/(206)Pb matches the test substance well. As for feces, when (204)Pb/(206)Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group. The biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for (204)Pb/(206)Pb ratio under high-dose exposure.

  7. A Case of Brugada Pattern Migrant from Right Precordial Leads to Peripheral Leads.

    Science.gov (United States)

    Luzza, Francesco; Crea, Pasquale; Nicotera, Angela; Picciolo, Giuseppe; Pugliatti, Pietro; Oreto, Giuseppe

    2016-05-01

    Since the first report in 1992, Brugada pattern (BP) diagnosis is mainly based on analysis of the precordial leads. In cases with no clear BP evidence in the conventional right precordial leads (4th intercostal space), limb leads analysis resulted helpful in suspecting BP. Fluctuations within right precordial leads between the diagnostic ECG pattern and nondiagnostic ECGs are well known. For the first time, in the patient herewith reported, the transformation of BP phenotype involves both precordial and peripheral leads, confirming that the analysis of all the 12 leads has a key role in BP diagnosis. © 2015 Wiley Periodicals, Inc.

  8. Acute Lead Poisoning In an Infant

    OpenAIRE

    Madhusudhanan, M.; Lall, S.B.

    2007-01-01

    A case of acute lead poisoning in an infant without overt clinical manifestations of encephalopathy is reported for the first time in Oman. The case was diagnosed at Rustaq Hospital on the basis of (i) history by the mother of giving the child a traditional remedy for treating constipation (ii) X-ray of abdomen showing radio-opaque speckles and (iii) detection of high blood lead levels (83.3 µg/dL) at the toxicology laboratory of the poison control centre. The source of lead was confirmed by ...

  9. Lead hepatotoxicity: Selected aspects of pathobiochemistry

    Directory of Open Access Journals (Sweden)

    Mateusz Labudda

    2013-08-01

    Full Text Available Lead (Pb that belongs to heavy metals is one of the major pollution components of the environment. Occupational and environmental exposure to lead can cause its absorption by the body and consequently exert toxic effects in the liver. In this paper biochemical determinants of hepatotoxicity caused by lead are presented. Generation of reactive oxygen species, disturbances in the cellular antioxidant system, lipid peroxidation, inhibition of enzymatic proteins and intercellular signaling are also discussed. Med Pr 2013;64(4:565–568

  10. Suspected lead toxicosis in a bald eagle

    Science.gov (United States)

    Jacobson, E.; Carpenter, J.W.; Novilla, M.

    1977-01-01

    An immature bald eagle (Haliaeetus leucocephalus) was submitted to the University of Maryland, College Park, for clinical examination. The bird was thin, had green watery feces, and was unable to maintain itself in upright posture. Following radiography, the bird went into respiratory distress and died. Numerous lead shot were recovered from the gizzard, and chemical analysis of liver and kidney tissue revealed 22.9 and 11.3 ppm lead, respectively. The clinical signs, necropsy findings, and chemical analysis of the eagle were compatible with lead toxicosis.

  11. OSHA issues new guidelines on lead.

    Science.gov (United States)

    1979-12-07

    The OSHA (Occupational Safety and Health Administration) issued new lead exposure standards which were effective February 1979. The policy provides that workers in childbearing years should receive protected earnings and benefits for 18 months while temporarily removed from their regular job to one with less lead exposure. Excessive lead exposure can reduce sex drive, cause impotence and sterility in men, and cause reduced fertility and menstrual disorders in women. Children of exposed parents may have birth defects, mental retardation, or die in their first year.

  12. Pb Neurotoxicity: Neuropsychological Effects of Lead Toxicity

    Directory of Open Access Journals (Sweden)

    Lisa H. Mason

    2014-01-01

    Full Text Available Neurotoxicity is a term used to describe neurophysiological changes caused by exposure to toxic agents. Such exposure can result in neurocognitive symptoms and/or psychiatric disturbances. Common toxic agents include heavy metals, drugs, organophosphates, bacterial, and animal neurotoxins. Among heavy metal exposures, lead exposure is one of the most common exposures that can lead to significant neuropsychological and functional decline in humans. In this review, neurotoxic lead exposure's pathophysiology, etiology, and epidemiology are explored. In addition, commonly associated neuropsychological difficulties in intelligence, memory, executive functioning, attention, processing speed, language, visuospatial skills, motor skills, and affect/mood are explored.

  13. Mission-Area Guide to Lead-Exposure Control

    Science.gov (United States)

    1996-03-01

    Lead-Exposure Control March 1996 63 DOD Memorandum, SUBJECT: Modification of Pediatric Blood Lead Screening Program, June 26, 1995. Universal...contain lead compounds in dyes (lead acetate, lead dioxide, lead chromate, and lead nitrate) and in coatings (waterproof fabric contains lead resinate ...resistance to corrosion, and biocompatibility. Dental materials containing metals and metal alloys include amalgams, impressions, fillings, crowns

  14. Distribution of lead in human milk fractions: relationship with essential minerals and maternal blood lead.

    Science.gov (United States)

    Anastácio, Alexandra da Silva; da Silveira, Carmem Lucia Porto; Miekeley, Norbert; Donangelo, Carmen Marino

    2004-01-01

    The purpose of this study was to determine the concentration and distribution of lead, calcium, iron, zinc, and copper in major fractions (fat, casein, whey) of mature milk from 38 nursing adult women with low environmental lead exposure. The potential associations between milk lead and maternal blood lead and between milk and blood lead and essential mineral data (nutritional status, dietary intake, and milk concentration) were investigated. Maternal blood lead (geometric mean, 60 microg/L) was negatively associated, although modestly, with dietary calcium intake (r=-0.32, p=0.02). Lead in whole milk (geometric mean, 1.2 microg/L) was positively associated with calcium in whole milk (r=0.56, p=0.005). Distribution of lead in milk fractions was 63%, 28%, and 9%, in whey, fat, and casein, respectively. Milk distribution of essential minerals was 67-76%, 17-18%, and 7-17% in whey, fat, and casein, respectively. Lead in milk whey was positively associated with lead in maternal blood (r=0.49, p=0.02). However, milk lead was not affected by nutritional status, dietary intake, and milk composition of the essential minerals. The high percentage of lead in the milk whey fraction, as seen for the essential minerals, suggests that most lead in human milk is bioavailable to the infant.

  15. Lead identification in soil surrounding a used lead acid battery smelter area in Banten, Indonesia

    Science.gov (United States)

    Adventini, N.; Santoso, M.; Lestiani, D. D.; Syahfitri, W. Y. N.; Rixson, L.

    2017-06-01

    A used lead acid battery smelter generates particulates containing lead that can contaminate the surrounding environment area. Lead is a heavy metal which is harmful to health if it enters the human body through soil, air, or water. An identification of lead in soil samples surrounding formal and informal used lead acid battery smelters area in Banten, Indonesia using EDXRF has been carried out. The EDXRF accuracy and precision evaluated from marine sediment IAEA 457 gave a good agreement to the certified value. A number of 16 soil samples from formal and informal areas and 2 soil samples from control area were taken from surface and subsurface soils. The highest lead concentrations from both lead smelter were approximately 9 folds and 11 folds higher than the reference and control samples. The assessment of lead contamination in soils described in Cf index was in category: moderately and strongly polluted by lead for formal and informal lead smelter. Daily lead intake of children in this study from all sites had exceeded the recommended dietary allowance. The HI values for adults and children living near both lead smelter areas were greater than the value of safety threshold 1. This study finding confirmed that there is a potential health risk for inhabitants surrounding the used lead acid battery smelter areas in Banten, Indonesia.

  16. Coronary Sinus Lead Removal: A Comparison between Active and Passive Fixation Leads.

    Science.gov (United States)

    Pecha, Simon; Kennergren, Charles; Yildirim, Yalin; Gosau, Nils; Aydin, Ali; Willems, Stephan; Treede, Hendrik; Reichenspurner, Hermann; Hakmi, Samer

    2016-01-01

    Implantation of coronary sinus (CS) leads may be a difficult procedure due to different vein anatomies and a possible lead dislodgement. The mode of CS lead fixation has changed and developed in recent years. We compared the removal procedures of active and passive fixation leads. Between January 2009 and January 2014, 22 patients at our centre underwent CS lead removal, 6 active and 16 passive fixation leads were attempted using simple traction or lead locking devices with or without laser extraction sheaths. Data on procedural variables and success rates were collected and retrospectively analyzed. The mean patient age was 67.2 ± 9.8 years, and 90.9% were male. The indication for lead removal was infection in all cases. All active fixation leads were Medtronic® Attain StarFix™ Model 4195 (Medtronic Inc., Minneapolis, MN, USA). The mean time from implantation for the active and passive fixation leads was 9.9 ± 11.7 months (range 1.0-30.1) and 48.7 ± 33.6 months (range 5.7-106.4), respectively (p = 0.012). Only 3 of 6 StarFix leads were successfully removed (50%) compared to 16 of 16 (100%) of the passive fixation CS leads (p = 0.013). No death or complications occurred during the 30-day follow-up. According to our experience, removal of the Starfix active fixation CS leads had a higher procedural failure rate compared to passive.

  17. NCHS - Leading Causes of Death: United States

    Data.gov (United States)

    U.S. Department of Health & Human Services — This dataset presents the age-adjusted death rates for the 10 leading causes of death in the United States beginning in 1999. Data are based on information from all...

  18. Mining, habitats lead space architecture work

    National Research Council Canada - National Science Library

    David Nixon

    2013-01-01

      Nixon narrates how space mining habitats lead space architecture work. NASA's current focus on an asteroid rendezvous mission as human space exploration's next big goal has begun to stimulate ideas from the space community at large...

  19. NIH Research Leads to Cervical Cancer Vaccine

    Science.gov (United States)

    ... Transmitted Diseases NIH Research Leads to Cervical Cancer Vaccine Past Issues / Fall 2008 Table of Contents For ... Douglas Lowy (left) and John Schiller developed the vaccine to prevent HPV infection in women, the cause ...

  20. The Earliest Lead Object in the Levant.

    Directory of Open Access Journals (Sweden)

    Naama Yahalom-Mack

    Full Text Available In the deepest section of a large complex cave in the northern Negev desert, Israel, a bi-conical lead object was found logged onto a wooden shaft. Associated material remains and radiocarbon dating of the shaft place the object within the Late Chalcolithic period, at the late 5th millennium BCE. Based on chemical and lead isotope analysis, we show that this unique object was made of almost pure metallic lead, likely smelted from lead ores originating in the Taurus range in Anatolia. Either the finished object, or the raw material, was brought to the southern Levant, adding another major component to the already-rich Late Chalcolithic metallurgical corpus known to-date. The paper also discusses possible uses of the object, suggesting that it may have been used as a spindle whorl, at least towards its deposition.

  1. Loneliness May Lead to Sleepless Nights

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_166146.html Loneliness May Lead to Sleepless Nights Study suggests that ... 1, 2017 THURSDAY, June 1, 2017 (HealthDay News) -- Loneliness may rob you of your sleep, British researchers ...

  2. Current practice in transvenous lead extraction

    DEFF Research Database (Denmark)

    Bongiorni, Maria Grazia; Blomström-Lundqvist, Carina; Kennergren, Charles

    2012-01-01

    AIM: Current practice with regard to transvenous lead extraction among European implanting centres was analysed by this survey. METHODS AND RESULTS: Among all contacted centres, 164, from 30 countries, declared that they perform transvenous lead extraction and answered 58 questions...... with a compliance rate of 99.9%. Data from the survey show that there seems to be an overall increasing experience of managing various techniques of lead extraction and a widespread involvement of cardiac centres in this treatment. Results and complication rates seem comparable with those of main international...... registries. CONCLUSION: This survey gives an interesting snapshot of lead extraction in Europe today and gives some clues for future research and prospective European registries....

  3. Environmental lead exposure increases micronuclei in children

    DEFF Research Database (Denmark)

    Kapka, Lucyna; Baumgartner, Adolf; Siwińska, Ewa

    2007-01-01

    The objective of this pilot study was to investigate the contribution of environmental exposures to lead in the development of cytogenetic damage detected as the frequency of micronuclei (MN) in children. The other aim was to apply the MN assay in combination with fluorescence in situ hybridization...... age from an unexposed recreational area. Exposure to lead was assessed by determination of lead concentrations in blood (PbB) by atomic absorption spectrophotometry, whereas the level of selenium (Se) in serum was detected by using graphite furnace atomic-absorption spectrometry. The frequency of MN...... was determined by the cytokinesis-block MN assay and fluorescence in situ hybridization performed using a specific pan-centromeric probe. Environmental exposure to lead resulted in significantly increased levels of PbB (5.29 +/- 2.09 versus 3.45 +/- 1.20 microg/dl in controls), although the average level...

  4. Asymptomatic congenital lead poisoning - case report.

    Science.gov (United States)

    Chinnakaruppan, Nachammai R; Marcus, Steven Matthew

    2010-07-01

    Congenital lead poisoning is uncommon and there is no consensus on the management of the newborn. A female infant was born to a lead-burdened woman identified by screening just prior to delivery. Maternal blood lead level (BLL) was 58 μg/dL. The infant's BLL on the second day of life was 72 μg/dL with a free erythrocyte protoporphyrin level of 175 μg/dL. The child was managed by an exchange transfusion followed by chelation. The BLL 6 h after exchange transfusion was 11.4 μg/dL. Follow-up 2 years later showed a BLL of 9 μg/dL and normal development. We present the details of a case of congenital lead poisoning treated aggressively which appears to have resulted in a favorable outcome.

  5. Ayurvedic herbal medicine and lead poisoning.

    Science.gov (United States)

    Gunturu, Krishna S; Nagarajan, Priyadharsini; McPhedran, Peter; Goodman, Thomas R; Hodsdon, Michael E; Strout, Matthew P

    2011-12-20

    Although the majority of published cases of lead poisoning come from occupational exposures, some traditional remedies may also contain toxic amounts of lead. Ayurveda is a system of traditional medicine that is native to India and is used in many parts of world as an alternative to standard treatment regimens. Here, we report the case of a 58-year-old woman who presented with abdominal pain, anemia, liver function abnormalities, and an elevated blood lead level. The patient was found to have been taking the Ayurvedic medicine Jambrulin prior to presentation. Chemical analysis of the medication showed high levels of lead. Following treatment with an oral chelating agent, the patient's symptoms resolved and laboratory abnormalities normalized. This case highlights the need for increased awareness that some Ayurvedic medicines may contain potentially harmful levels of heavy metals and people who use them are at risk of developing associated toxicities.

  6. Ayurvedic herbal medicine and lead poisoning

    Directory of Open Access Journals (Sweden)

    Gunturu Krishna S

    2011-12-01

    Full Text Available Abstract Although the majority of published cases of lead poisoning come from occupational exposures, some traditional remedies may also contain toxic amounts of lead. Ayurveda is a system of traditional medicine that is native to India and is used in many parts of world as an alternative to standard treatment regimens. Here, we report the case of a 58-year-old woman who presented with abdominal pain, anemia, liver function abnormalities, and an elevated blood lead level. The patient was found to have been taking the Ayurvedic medicine Jambrulin prior to presentation. Chemical analysis of the medication showed high levels of lead. Following treatment with an oral chelating agent, the patient's symptoms resolved and laboratory abnormalities normalized. This case highlights the need for increased awareness that some Ayurvedic medicines may contain potentially harmful levels of heavy metals and people who use them are at risk of developing associated toxicities.

  7. How lead loses its toxicity to plants

    National Research Council Canada - National Science Library

    Małgorzata Wierzbicka

    2014-01-01

    .... This surprising result is in agreement with the absence of any symptoms of lead poisoning in plants growing in natural conditions, and suggests that there is a defence mechanism specific only for plant cells.

  8. Treating Lead Toxicity: Possibilities beyond Synthetic Chelation

    Directory of Open Access Journals (Sweden)

    Shambhavi Tannir

    2013-01-01

    Full Text Available Lead, a ubiquitous metal, is one of the most abundant elements present on earth. Its easy availability and cost effectiveness made it an extremely popular component in the industrial revolution. However, its hazardous health effects were not considered at the time. Over the last few decades, with the adverse effects of lead coming to the forefront, nations across the world have started to recognize and treat lead toxicity. The most reliable and used method until now has been chelation therapy. Recent research has suggested the use of natural products and sources to treat lead poisoning with minimal or no side effects. This review has tried to summarize a few of the natural products/sources being investigated by various groups.

  9. FastStats: Leading Causes of Death

    Science.gov (United States)

    ... Chronic Sinusitis Whooping Cough or Pertussis Family Life Marriage and Divorce Health Care and Insurance Access to ... Cause of Death Contribute to the Hispanic Mortality Advantage in the United States? Leading Causes of Death ...

  10. Lead State Implementation Plan (SIP) Checklist Guide

    Science.gov (United States)

    Guidance documents and examples to assist air quality agencies of non-attainment areas in developing plans to implement national ambient air quality standards (NAAQS), including the lead air emissions standard.

  11. Effects of lead on plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Fiussello, N.; Molinari, M.T.

    1973-01-01

    The poisonousness of lead nitrate to seedlings of several plant species has been tested in Petri dishes, with 10/sup -1/, 10/sup -2/, 10/sup -3/, 10/sup -4/ M conc. Distilled water and KNO/sub 3/ solutions 2 X 10/sup -1/, 2 X 10/sup -2/, 2 X 10/sup -3/, 2 X 10/sup -4/ M were employed as controls. The tested species show a decreasing sensitivity: Capsicum annum > Beta vulgaris > Phalaris canariensis > Vicia sativa > Helianthus annuus > Oryza sativa > Triticum vulgare Avena sativa > Pisum sativum. Avena sativa shows a diminution of 34% in ww, 23% in dw, 26% in chlorophyll content in comparison with the controls after 21 days 10/sup -4/ M lead nitrate. The chlorophyll content, referred to dry weight, is related to lead concentration. Since the early stages of chlorophyll biosynthesis are similar, if not identical, with those for Haemoglobin, lead could interfere as it does in haemoglobin synthesis.

  12. Lead sulphate leaching by sodium chloride solution

    National Research Council Canada - National Science Library

    Conić Vesna T; Pešovski Branka D; Cvetkovski Vladimir B; Stanojević-Šimšić Zdenka S; Dragulović Suzana S; Simonović Danijela B; Dimitrijević Silvana B

    2013-01-01

    Bioleaching treatment of complex multi-metallic Cu-Zn-Pb-Ag-Au mineral concentrates leds to the formation, besides easily soluble zinc and cooper sulphates, of hardly soluble lead (II) sulfate (PbSO4) sludge...

  13. Superconducting Current Leads for Cryogenic Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space flight cryocoolers will be able to handle limited heat loads at their expected operating temperatures and the current leads may be the dominant contributor to...

  14. Distribution of Lead in Kerbside Soils

    African Journals Online (AJOL)

    NJD

    Leaded petrol was used on a large scale at the time this study was being carried out. The toxicity of lead to .... 2.4. Calibration of AAS, ICP-AES and GF-AAS. A multi-point calibration was used to optimize and calibrate ... calibration line obtained by plotting the data obtained. The same procedure was used for the other two ...

  15. Letting the Data Lead the Code

    Science.gov (United States)

    2015-08-01

    UNCLASSIFIED Page 1 of 4 UNCLASSIFIED: Distribution Statement A. Approved for public release. Letting the Data Lead the Code Darryl Bryk...31 AUG 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Letting the Data Lead the Code 5a. CONTRACT NUMBER...int.TryParse(s[i], out inum)) ilist.Add(inum

  16. Renovate Right: Prevent Lead Poisoning in Children

    Centers for Disease Control (CDC) Podcasts

    2008-10-02

    In this podcast, Dr. Maria Doa, Director of the Environmental Protection Agency's (EPA) National Program Chemicals Division, discusses EPA's new rule for renovations, repairs, and painting activities. The new rule includes information on lead-safe work practices when conducting renovations, repairs, and painting in pre-1978 homes and schools to prevent the spread of lead dust.  Created: 10/2/2008 by National Center for Environmental Health (NCEH).   Date Released: 10/2/2008.

  17. Lead Toxicity Risks in Gunshot Victims.

    Directory of Open Access Journals (Sweden)

    Gabriel Costa Serrão de Araújo

    Full Text Available Gunshot wounds require surgeons to decide whether to remove or leave bullet fragments in the body. Surgeons also decide how to follow up with patients who have lead fragments retained in their body. Current literature recommends to remove only intra-articular fragments without the need for a follow-up for patients with the metal retained. Therefore, this study investigates chronic lead toxicity for gunshot wounds.The study was performed in the metropolitan area of Rio de Janeiro/Brazil, between 2013 and 2015. It was a case-control study that included 45 victims of gunshot lesions with metallic fragments retained for more than 6 months. The 45 controls were matched for gender, age, and race. We compared the lead blood levels and frequency of symptoms.The control group had average blood lead levels of 2.17 μg/dL (95% Confidence Interval [CI]; 1.71-2.63 and median 2.1 μg/dL. The case group had average values of 9.01 μg/dL (CI; 6.07-11.96 and median values of 6.5 μg/dL with p-values < = 0.001. The case group reported the following more frequently: irritancy, bad mood, headache, memory losses, daylight drowsiness, myalgia, weakness, abdominal pain, joint pain, trembling, tingling limbs. There was statistical significance for the differences of symptoms frequencies and for odds ratio between groups.Although the mean lead levels found were lower than the current laboratory references, low levels have been associated with both rising morbidity and mortality. The WHO stated: "There is no known level of lead exposure that is considered safe". In conclusion, this work showed that bullets retained in the body are not innocuous. There are impacts in the blood lead levels and symptoms related to it, even with few fragments, extra-articular located or existing with low blood lead levels.

  18. Oral lead exposure induces dysbacteriosis in rats.

    Science.gov (United States)

    Sadykov, Rustam; Digel, Ilya; Artmann, Aysegül Temiz; Porst, Dariusz; Linder, Peter; Kayser, Peter; Artmann, Gerhard; Savitskaya, Irina; Zhubanova, Azhar

    2009-01-01

    Lead's (Pb(II)) possible role in intestinal pathologies of microbial etiology remains mostly unknown. The aim of this study was to examine the effects of lead on the gut microbial community and its interactions with rat intestinal epithelium. The lead-induced changes in different intestinal microbial groups (lactose-positive lac(+) and -negative lac(-) E.coli strains, lactobacilli and yeasts) were followed separately by the colony-forming unit (CFU) method. Samples were taken from outbred white rats subjected to different exposure schedules. Additionally, the impact of different lead doses on microbial adhesion to cultured intestinal cells (IEC-6) was investigated. Finally, the lead accumulation and distribution were measured by means of atomic absorption spectrometry. For the first time it was shown that oral lead exposure causes drastic changes in the gut microbial community. Proportional to the lead dose received, the relative number of lactose-negative E.coli cells increased dramatically (up to 1,000-fold) in comparison to the other microbial groups during 2 wk of exposure. Considering the number of microbes in the intestine, such a shift in intestinal microflora (dysbacteriosis) is very significant. Adhesion studies showed certain stimulating effects of lead on E. coli attachment to rat intestinal epithelium as compared to Lactobacillus attachment. The mechanisms providing the apparent competitive success of the lac(-) group are unclear but could be related to changes in surface interactions between microbial and host cells. This study may provide important clues for understanding the pathological effects of metal dietary toxins in human beings.

  19. EPA Leads the Way on Lead Exposure Science and Risk Management

    Science.gov (United States)

    EPA researchers have developed a modeling approach that improves our understanding of the relationship between lead concentrations of various sources (drinking water, soil and dust, food, and air) and children’s blood-lead levels.

  20. Corrosion by liquid lead and lead-bismuth: experimental results review and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jinsuo [Los Alamos National Laboratory

    2008-01-01

    Liquid metal technologies for liquid lead and lead-bismuth alloy are under wide investigation and development for advanced nuclear energy systems and waste transmutation systems. Material corrosion is one of the main issues studied a lot recently in the development of the liquid metal technology. This study reviews corrosion by liquid lead and lead bismuth, including the corrosion mechanisms, corrosion inhibitor and the formation of the protective oxide layer. The available experimental data are analyzed by using a corrosion model in which the oxidation and scale removal are coupled. Based on the model, long-term behaviors of steels in liquid lead and lead-bismuth are predictable. This report provides information for the selection of structural materials for typical nuclear reactor coolant systems when selecting liquid lead or lead bismuth as heat transfer media.

  1. [Environmental lead poisoning from lead-glazed earthenware used for storing drinks].

    Science.gov (United States)

    Sabouraud, S; Coppéré, B; Rousseau, C; Testud, F; Pulce, C; Tholly, F; Blanc, M; Culoma, F; Facchin, A; Ninet, J; Chambon, P; Medina, B; Descotes, J

    2009-12-01

    Current unusual environmental sources of lead exposure mainly include traditional medicines, either ayurvedic remedies or others, traditional cosmetics (kohl, surma), and the use of traditional earthenware, for storage or cooking. We report two cases of lead poisoning in adults initially identified by paroxysmal abdominal pain or anemia. In both cases, the environmental investigation evidenced one main source of lead exposure, namely a lead-glazed earthenware jug in which a drink was stored, "kefir" in the first case, and "kombucha" tea in the second one. It is recommended to search for lead intoxication in patients with unexplained anemia. Environmental sources of lead can be multiple. Their relative importance has to be ranked during the environmental investigation and among these, lead-glazed earthenware must be considered as a source of high lead exposure when drinks are stored inside and thus can soak.

  2. Investigations on organolead compounds V. Lead---lead bond cleavage reactions of hexaphenyldilead

    NARCIS (Netherlands)

    Willemsens, L.C.; Kerk, G.J.M. van der

    1968-01-01

    It has been shown that a number of nucleophilic and weakly electrophilic reagents (organolithium and organomagnesium compounds, metallic lithium, potassium permanganate, sodium ethoxide, diaryl disulphides, sulphur, ozone, hypochlorous acid and iodine/iodide) selectively cleave the lead---lead bond

  3. Acute lead poisoning in an infant.

    Science.gov (United States)

    Madhusudhanan, M; Lall, S B

    2007-10-01

    A case of acute lead poisoning in an infant without overt clinical manifestations of encephalopathy is reported for the first time in Oman. The case was diagnosed at Rustaq Hospital on the basis of (i) history by the mother of giving the child a traditional remedy for treating constipation (ii) X-ray of abdomen showing radio-opaque speckles and (iii) detection of high blood lead levels (83.3 µg/dL) at the toxicology laboratory of the poison control centre. The source of lead was confirmed by high content of inorganic lead (20.2%) found in the sample of the traditional remedy (bint al dahab). The blood lead levels significantly decreased, after the intravenous calcium edetate (EDTA) therapy was given to the baby. The case highlights that early detection and treatment of acute lead poisoning in children can prevent morbidity and sequelae associated with encephalopathy. It also indicated the need for awareness and prevention programme for parents on this issue.

  4. Environmentally sound technologies for recycling secondary lead

    Science.gov (United States)

    Andrews, D.; Raychaudhuri, A.; Frias, C.

    Advances in hydrometallurgy are providing increasingly simple means for controlling the entire lead chain from concentrate to recycled lead. Used in parallel with pyrometallurgy, these processes allow furnace temperatures to be reduced to the minimum, which is essential for casting or alloying. Fumes and atmospheric pollution are minimized, furnace slags are digested, and most residues (other than purification cements) are non-toxic and convertible into marketable products. These new processes provide the cleanest and healthiest practicable means for recycling lead from batteries. By substituting melting for smelting, the heat requirement and cycle time per charge are reduced by more than half. A new hydrometallurgical plant could be installed alongside an existing pyrometallurgical plant without interference, doubling its potential capacity when operational (and more, if electrowinning is used). Over 99.5% of the lead originally present is recovered in tests of a combined PLACID-pyro plant. The average purity of electrowon PLACID lead is 99.995%. Results from the PLINT process should be similar. The purity of the lead chain can thereby be sustained through recycling. Perfect solid/paste separation is not mandatory, and PLINT-type plant units can be of any size. Such processes constitute a good basis for development of clean processes, which are suitable for use in Asian societies.

  5. Blood lead levels and chronic blood loss

    Energy Technology Data Exchange (ETDEWEB)

    Manci, E.A.; Cabaniss, M.L.; Boerth, R.C.; Blackburn, W.R.

    1986-03-01

    Over 90% of lead in blood is bound to the erythrocytes. This high affinity of lead for red cells may mean that chronic blood loss is a significant means for excretion of lead. This study sought correlations between blood lead levels and clinical conditions involving chronic blood loss. During May, June and July, 146 patients with normal hematocrits and red cell indices were identified from the hospital and clinic populations. For each patient, age, race, sex and medical history were noted, and a whole blood sample was analyzed by flameless atomic absorption spectrophotometry. Age-and race-matched pairs showed a significant correlation of chronic blood loss with lead levels. Patients with the longest history of blood loss (menstruating women) had the lowest level (mean 6.13 ..mu..g/dl, range 3.6-10.3 ..mu..g/dl). Post-menopausal women had levels (7.29 ..mu..g/dl, 1.2-14 ..mu..g/dl) comparable to men with peptic ulcer disease, or colon carcinoma (7.31 ..mu..g/dl, 5.3-8.6 ..mu..g/dl). The highest levels were among men who had no history of bleeding problems (12.39 ..mu..g/dl, 2.08-39.35 ..mu..g/dl). Chronic blood loss may be a major factor responsible for sexual differences in blood lead levels. Since tissue deposition of environmental pollutants is implicated in diseases, menstruation may represent a survival advantage for women.

  6. 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.

  7. Extraction of chronically implanted coronary sinus leads active fixation vs passive fixation leads.

    Science.gov (United States)

    Crossley, George H; Sorrentino, Robert A; Exner, Derek V; Merliss, Andrew D; Tobias, Serge M; Martin, David O; Augostini, Ralph; Piccini, Jonathan P; Schaerf, Raymond; Li, Shelby; Miller, Clayton T; Adler, Stuart W

    2016-06-01

    The Medtronic model 4195 (StarFix) left ventricular lead is an active fixation lead that provides additional support within the coronary sinus (CS) via deployable lobes. While this lead has been shown to have excellent stability within the CS, concerns about its extractability have been raised. The aim of this study was to compare the safety and efficacy of the extraction of the model 4195 lead vs other Medtronic CS leads in a prospective cohort study. Patients undergoing extraction of this and other CS leads for standard indications were prospectively enrolled and studied. The primary outcomes of interest were the removal success rates and associated complication rates. Patients were followed for a month postprocedure. The overall left ventricular lead extraction success rate was 97.6% (n = 205). Among 40 patients with chronic model 4195 leads, there were 37 successful extractions (92.5%) as compared to 98.8% for the 165 non-4195 leads. However, in 2 of the 3 StarFix lead extraction failures, standard extraction techniques were not used. All 10 of the model 4195 leads that had been implanted for less than 6 months were extracted without incident. In this largest study of CS lead extractions published to date, the overall success rate of the extraction of chronically implanted CS leads is high and the complication rate is similar in these lead models. The extraction of the model 4195 lead is clearly more challenging, but it can be accomplished in high-volume extraction centers with experienced operators. It is recommended that the model 4195 lead be extracted by experienced operators. Copyright © 2016. Published by Elsevier Inc.

  8. Leading by example to protect the environment : Do the costs of leading matter?

    NARCIS (Netherlands)

    van der Heijden, E.C.M.; Moxnes, E.

    2013-01-01

    Environmentalists often urge their home countries to take a leading role in reducing global environmental problems like climate change. A pertinent question is, Will examples set by leading nations influence others to follow suit, and if so, do the costs of leading matter? For instance, will costly

  9. Leading by Example to Protect the Environment; Do the Costs of Leading Matter?

    NARCIS (Netherlands)

    van der Heijden, E.C.M.; Moxnes, E.

    2011-01-01

    Environmentalists often urge their home countries to take a leading role in reducing global environmental problems like climate change. A pertinent question is: will examples set by leading nations influence others to follow suit, and if so, do the costs of leading matter? For instance, will costly

  10. 75 FR 43942 - Children's Products Containing Lead; Technological Feasibility of 100 ppm for Lead Content...

    Science.gov (United States)

    2010-07-27

    ... COMMISSION Children's Products Containing Lead; Technological Feasibility of 100 ppm for Lead Content... content limit for children's products. DATES: Written comments and submissions in response to this notice... for children 12 years old and younger, the total lead content limit by weight in any part of a...

  11. Lead-Free vs Tin-Lead Reliability of Advanced Electronic Assemblies

    Science.gov (United States)

    Ghaffarian, Reza

    2005-01-01

    This presentation will provide the technical background and specific information published in literature related to reliability test, analyses, modeling, and associated issues for lead-free solder package assemblies in comparison to their tin-lead solder alloys. It also presents current understanding of lead-free thermal cycle test performance in support.

  12. Association of defects in lead chloride and lead bromide: Ionic conductivity and dielectric loss measurements

    NARCIS (Netherlands)

    Brom, W.E. van den; Schoonman, J.; Wit, J.H.W. de

    The ionic conductivity data of pure and doped lead bromide without associated defects are used in order to explain the anomalous conductivity behaviour of copper (I) bromide and lead oxide-doped lead-bromide crystals. In these crystals precipitated dopant and associated defects are present. The

  13. Do newspapers lead with lead? A content analysis of how lead health risks to children are covered.

    Science.gov (United States)

    Brittle, Christine; Zint, Michaela

    2003-06-01

    Lead poses a serious environmental health risk to young children, causing such irreversible health effects as mental retardation, stunted growth, and hearing and visual impairment. Studies suggest that various sectors of the public, including children's caregivers, are not sufficiently concerned about this risk or knowledgeable about ways of minimizing it. Because newspapers are one of the primary ways members of the public learn about risks, the authors examined the characteristics and content of 152 newspaper articles on lead to determine when coverage occurred and what information was provided. Results revealed that newspapers most often covered lead as a local news story. Few articles identified children under six years of age as the most vulnerable group or provided important information on health effects, sources of exposure, or abatement methods. The authors' recommendations focus on helping environmental health professionals work with newspaper journalists to improve the information available to the public.

  14. Environmental lead in Mexico, 1990-2002.

    Science.gov (United States)

    Flores, Julio; Albert, Lilia A

    2004-01-01

    From the data presented here, it can be concluded that despite some important progress in recent years, in particular, the phaseout of the use of lead in gas, environmental exposure to lead remains a particularly severe problem in Mexico. The lack of recent and adequate information on the presence of lead in air, dust, soil, surface waters, the marine environment, and food is noteworthy. In particular, there are no data on the presence of lead in the environment of industrial cities or in areas where mining and metallurgical activities are predominant, including their nearby environment, such as river sediments or air, and in their inhabitants. As a result, the official conclusion that the major present source of lead for Mexicans is the manufacture and use of lead-glazed ceramics, and the few official actions in this regard lack a solid basis because they rely on data from a few limited studies carried out mainly in Mexico City and its Metropolitan Zone. Although there have been few studies in Mexico on the adverse effects of long-term exposure to lead, the data provided on its presence in human milk, lungs, and bones and the results of the scant studies on its neuropsychological effects on children should be taken into consideration to establish more effective control and protective measures and to support the additional studies required to document the present situation. In particular, more studies should be carried out in lead glazed-ceramic-producing communities and on the hazards of lead to the communities established near industrial areas and along river banks. In future studies, special attention should be paid to establishing a common protocol, with adequate analytical control measures, if possible, with intercalibration of the participating laboratories; this is essential, because at present many of the available data cannot be compared or extrapolated due to their deficiencies in this regard. The situation around the only primary lead smelter in Mexico

  15. Increasing lead burden correlates with externalized cables during systematic fluoroscopic screening of Riata leads.

    Science.gov (United States)

    Moorman, Liza P; Moorman, J Randall; DiMarco, John P; Malhotra, Rohit; Darby, Andrew; Bilchick, Kenneth; Ferguson, John D; Mangrum, J Michael; Kamath, Sandeep; Mason, Pamela K

    2013-06-01

    Riata and Riata ST defibrillator leads (St. Jude Medical, Sylmar, CA, USA) have been recalled due to increased risk of insulation failure leading to externalized cables. As this mechanical failure does not necessarily correlate with electrical failure, it can be difficult to diagnose. Fluoroscopic screening can identify insulation failure. Studies have suggested that insulation failure is predominantly seen in 8-Fr, single-coil models. Our patients have exclusively dual-coil leads and a high proportion of 7-Fr leads. Fluoroscopic screening was performed in 48 patients with recalled Riata leads. Twenty-three patients had 8-Fr Riata leads and 25 patients had 7-Fr Riata ST leads. Images were recorded in at least three projections and studies were reviewed by seven attending electrophysiologists. Externalized cables were seen in ten patients (21 %), and another five patients (10 %) had abnormal cable spacing. All device interrogations showed normal parameters. Patients with abnormal leads had more leads in situ (2.5 ± 0.7 vs. 1.6 ± 0.8 leads; P = 0.002) and a higher rate of nonischemic cardiomyopathy (80 vs. 24 %; P = 0.03). There were no differences between the groups with regards to patient age, body mass index, lead age, lead parameters, or vascular access site. There was no difference with regard to lead size (P = 0.76). The Riata family of leads has a high incidence of mechanical failure, as demonstrated on fluoroscopic screening. In this study, the 7-Fr models were just as likely to mechanically fail as the 8-Fr models. Increasing lead burden and a diagnosis of nonischemic cardiomyopathy correlated with insulation failure.

  16. Childhood lead poisoning and the new Centers for Disease Control and Prevention guidelines for lead exposure.

    Science.gov (United States)

    Schnur, Julie; John, Rita Marie

    2014-05-01

    This article will give a brief history, review the latest guidelines, discuss risk factors and sources, and discuss screening, diagnosis, and management of lead poisoning in children. Additionally, the role of the nurse practitioner (NP) caring for children will be reviewed. Review of published literature on lead poisoning and the 2012 lead prevention guidelines of the Advisory Committee on Childhood Lead Poisoning Prevention (ACCLPP) of the Centers for Disease Control and Prevention (CDC). While lead poisoning levels have decreased over the past several decades, newer research has shown that even low levels of lead in the blood can have negative effects on children's intelligence and neurodevelopment. As a result, ACCLPP of the CDC issued new, stricter lead prevention guidelines in 2012. Lead exposure and lead poisoning are pediatric public health risks. Studies have shown that no level of lead is considered safe, and the emphasis has shifted to primary prevention of lead exposure. Despite the focus on primary prevention, the NP must remain vigilant in history taking, exploring risk factors, and screening children in order to assure the best possible outcome. ©2014 The Author(s) ©2014 American Association of Nurse Practitioners.

  17. Environmentally sound technologies for recycling secondary lead

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, D. [Heathlands, Rugby (United Kingdom); Raychaudhuri, A. [VKA Associates, New Delhi (India); Frias, C. [Placid Processes, R and D Centre of Tecnicas Reunidas Sierra Nevada, Madrid (Spain)

    2000-05-01

    Advances in hydrometallurgy are poviding increasingly simple means for controlling the entire lead chain from concentrate to recycled lead. Used in parallel with pyrometallurgy, these processes allow furnace temperatures to be reduced to the minimum, which is essential for casting or alloying. Fumes and atmospheric pollution are minimized, furnace slags are digested, and most residues (other than purification cements) are non-toxic and convertible into marketable products. These new processes provide the cleanest and healthiest practicable means for recycling lead from batteries. By substituting melting for smelting, the heat requirement and cycle time per charge are reduced by more than half. A new hydrometallurgical plant could be installed alongside an existing pyrometallurgical plant without interference, doubling its potential capacity when operational (and more, if electrowinning is used). Over 99.5% of the lead originally present is recovered in tests of a combined PLACID-pyro plant. The average purity of electrowon PLACID lead is 99.995%. Results from the PLINT process should be similar. The purity of the chain can thereby be sustained through recycling. Perfect solid/paste separation is not mandatory, and PLINT-type plant units can be of any size. Such processes constitute a good basis for development of clean processes, which are suitable for use in Asian societies. (orig.)

  18. The Identification and Synthesis of Lead Apatite Minerals Formed in Lead Water Pipes

    Directory of Open Access Journals (Sweden)

    Jeremy D. Hopwood

    2016-01-01

    Full Text Available Phosphate is added to drinking water in the UK to minimise the release of lead from lead water pipes. The phosphate encourages the formation of insoluble lead apatites on the walls of the pipe. Hydroxylpyromorphite Pb5(PO43OH is the lead apatite that is most often used to model lead levels in tap water; however, its presence has not been confirmed. Our aims were to identify the lead pipe apatite and synthesise it. The synthetic mineral would then be used in future solubility studies to produce better predictions of lead levels in tap water. XRD and FTIR were used to characterise the minerals on a range of lead pipes. Pyromorphite and hydroxylpyromorphite were absent and instead a range of mixed calcium lead apatites were present. For every five lead ions in the general formula Pb5(PO43X between one and two ions were replaced with calcium and there was evidence of substitution of PO43- by either CO32- or HPO42-. Calcium lead apatites with similar unit cell dimensions to those found on lead water pipes were then synthesised. The calcium : lead ratio in these reaction mixtures was in excess of 500 : 1 and the resulting crystals were shown by TEM to be nanosized rods and flakes. The synthetic apatites that most closely resembled the unit cell dimensions of the apatites on lead water pipes were shown to be Pb3.4Ca1.3(PO43Cl0.03OH0.97, Pb3.6Ca1.2(PO43Cl0.07OH0.93, and Pb3.6Ca1.2(PO43Cl0.27OH0.73.

  19. Stable lead isotopic analyses of historic and contemporary lead contamination of San Francisco Bay estuary

    Science.gov (United States)

    Ritson, P.I.; Bouse, R.M.; Flegal, A.R.; Luoma, S.N.

    1999-01-01

    Variations in stable lead isotopic composition (240Pb, 206Pb, 207Pb, 208Pb) in three sediment cores from the San Francisco Bay estuary document temporal changes in sources of lead during the past two centuries. Sediment, with lead from natural geologic sources, and relatively homogeneous lead isotopic compositions are overlain by sediments whose isotopic compositions indicate change in the sources of lead associated with anthropogenic modification of the estuary. The first perturbations of lead isotopic composition in the cores occur in the late 1800s concordant with the beginning of industrialization around the estuary. Large isotopic shifts, toward lower 206Pb/207Pb, occur after the turn of the century in both Richardson and San Pablo Bays. A similar relationship among lead isotopic compositions and lead concentrations in both Bays suggest contamination from the same source (a lead smelter). The uppermost sediments (post 1980) of all cores also have a relatively homogenous lead isotopic composition distinct from pre-anthropogenic and recent aerosol signatures. Lead isotopic compositions of leachates from fourteen surface sediments and five marsh samples from the estuary were also analyzed. These analyses suggest that the lead isotopic signature identified in the upper horizons of the cores is spatially homogeneous among recently deposited sediments throughout the estuary. Current aerosol lead isotopic compositions [Smith, D.R., Niemeyer, S., Flegal, A.R., 1992. Lead sources to California sea otters: industrial inputs circumvent natural lead biodepletion mechanisms. Environmental Research 57, 163-175] are distinct from the isotopic compositions of the surface sediments, suggesting that the major source of lead is cycling of historically contaminated sediments back through the water column. Both the upper core sediments and surface sediments apparently derive their lead predominantly from sources internal to the estuary. These results support the idea that

  20. Effect of lead on root growth

    Directory of Open Access Journals (Sweden)

    Mouna eFAHR

    2013-06-01

    Full Text Available Lead (Pb is one of the most widespread heavy metal contaminants in soils. It is highly toxic to living organism. Pb has no biological function but can cause morphological, physiological and biochemical dysfunctions in plants. Plants have developed a wide range of tolerance mechanisms that are activated in response to lead exposure. Pb affects plants primarily through their root systems. Plant roots rapidly respond either (i by the synthesis and deposition of callose, creating a barrier that stops lead entering (ii through the uptake of large amounts of Pb and its sequestration in the vacuole accompanied by changes in root growth and branching pattern or (iii by its translocation to the aboveground parts of plant in the case of hyperaccumulators plants. Here we review the interactions of roots with the presence of Pb in the rhizosphere and the effect of Pb on the physiological and biochemical mechanisms of root development.

  1. Thermoforming plastic in lead shield construction.

    Science.gov (United States)

    Abrahams, M E; Chow, C H; Loyd, M D

    1989-09-01

    Radiation treatments using low energy X-rays or electrons frequently require a final field defining shield to be placed on the patient's skin. A custom made lead cut-out is used to provide a close fit to a particular patient's surface contours. We have developed a procedure which utilizes POLYFORM thermoplastic to obtain a negative mold of the patient instead of the traditional plaster bandage or dental impression gel. The Polyform is softened in warm water, molded carefully over the patient's surface, and is removed when "set" or hardened, usually within five minutes. Then lead sheet cut-outs can be formed within this negative. For shielding cut-outs requiring thicker lead sheet, a positive is made from dental stone using this Polyform negative. We have found this procedure to be neat, fast and comfortable for both patient and the dosimetrist.

  2. Thermoforming plastic in lead shield construction

    Energy Technology Data Exchange (ETDEWEB)

    Abrahams, M.E.; Chow, C.H.; Loyd, M.D. (Univ. of Texas Medical Branch, Galveston (USA))

    1989-09-01

    Radiation treatments using low energy X-rays or electrons frequently require a final field defining shield to be placed on the patient's skin. A custom made lead cut-out is used to provide a close fit to a particular patient's surface contours. We have developed a procedure which utilizes POLYFORM thermoplastic to obtain a negative mold of the patient instead of the traditional plaster bandage or dental impression gel. The Polyform is softened in warm water, molded carefully over the patient's surface, and is removed when set or hardened, usually within five minutes. Then lead sheet cut-outs can be formed within this negative. For shielding cut-outs requiring thicker lead sheet, a positive is made from dental stone using this Polyform negative. We have found this procedure to be neat, fast and comfortable for both patient and the dosimetrist.

  3. Industrial dynamics beyond the lead firms

    DEFF Research Database (Denmark)

    Haakonsson, Stine Jessen; Slepniov, Dmitrij

    Since the turn of the millennium, China has developed into a core location for the wind energy industry and is today the largest market for wind turbines. These developments have caught attention among scholars. However, most research is on the development of the market and the lead firm strategies...... for market access or on innovation, capability building and technology transfer in the industry. The main objective of this paper is to look ‘beyond the lead firms’. We seek to advance the understanding of how the recent changes in the industry affect producers of key components and their role...... in the industry. The paper employs a qualitative methodology, which draws on explorative case studies of sub-suppliers in the wind turbine industry in China. A special empirical focus is on the first tier sub-suppliers. As the Western lead firms establish themselves in China, the sub-suppliers also have...

  4. Leading-edge vortex lifts swifts.

    Science.gov (United States)

    Videler, J J; Stamhuis, E J; Povel, G D E

    2004-12-10

    The current understanding of how birds fly must be revised, because birds use their hand-wings in an unconventional way to generate lift and drag. Physical models of a common swift wing in gliding posture with a 60 degrees sweep of the sharp hand-wing leading edge were tested in a water tunnel. Interactions with the flow were measured quantitatively with digital particle image velocimetry at Reynolds numbers realistic for the gliding flight of a swift between 3750 and 37,500. The results show that gliding swifts can generate stable leading-edge vortices at small (5 degrees to 10 degrees) angles of attack. We suggest that the flow around the arm-wings of most birds can remain conventionally attached, whereas the swept-back hand-wings generate lift with leading-edge vortices.

  5. Chemically prepared lead magnesium niobate dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Tuttle, B.A.; Voigt, J.A.; Sipola, D.L.; Olson, W.R.; Goy, D.M.

    1998-11-01

    A chemical solution powder synthesis technique has been developed that produces first, uniform powders of lead magnesium niobate (PMN) with 60 to 80 nm crystallite size. The synthesis technique was based on the dissolution of lead acetate and alkoxide precursors in acetic acid followed by precipitation with oxalic acid/propanol solutions. Lead magnesium niobate ceramics fabricated from these chemically derived powders had smaller, more uniform grain size and higher dielectric constants than ceramics fabricated from mixed oxide powders that were processed under similar thermal conditions. Chem-prep PMN dielectrics with peak dielectric constants greater than 22,000 and polarizations in excess of 29 {micro}C/cm{sup 2} were obtained for 1,100 C firing treatments. Substantial decreases in dielectric constant and polarization were measured for chemically prepared PMN ceramics fired at lower temperatures, consistent with previous work on mixed oxide materials.

  6. Investigation of Multicomponent Lead-Free Solders

    Directory of Open Access Journals (Sweden)

    Gyenes A.

    2017-06-01

    Full Text Available According to the directives (RoHS and WEEE adopted by the European Union, lead has been banned from the manufacturing processes because of its health and environmental hazards. Therefore, the development of lead-free solders is one of the most important research areas of the electronic industry. This paper investigates multicomponent Sn-Ag-Cu based lead-free solders with different compositions. The properties of the six-component Innolot (SAC+BiSbNi and two low-Ag containing alloys were compared with the widespread used SAC307 solder. Microstructure investigations and X-ray diffraction measurements were performed to analyze and identify the formed phases, furthermore, tensile tests and microhardness measurements were executed to determine the mechanical properties of the examined solders.

  7. Optical anisotropy effects in lead tungstate crystals

    CERN Document Server

    Chipaux, Rémi

    1998-01-01

    The anisotropic crystal structure of lead tungstate leads to strong consequences in its optical properties and their characterization. Beyond the variation of surface reflections due to the birefringence of the material, we report the observation that part of the bulk light absorption is sensitive to the light polarization direction. This variable part varies with the quality of the crystal, and is clearly related to internal structural defects. Irradiation experiments with gamma rays or fast neutrons confirm the recent improvement of the short term resistance of this scintillator. Its long term behaviour remains identical, and acceptable for the use in high energy electromagnetic calorimetry. A polarization direction dependant induced absorption is observed, specially after high levels of radiation. Ray tracing programs in development for the simulation of the light yield in lead tungstate should take into account all these anisotropic effects.

  8. Materials aspects of implantable cardiac pacemaker leads.

    Science.gov (United States)

    Bruck, S D; Mueller, E P

    1988-01-01

    The reliability of the leads of the entire pacemaker system is vital as the risks of failure include: (1) loss of pacing due to the deterioration of the polymeric insulator in the physiological environment; (2) thromboembolism due to inadequate blood compatibility of the insulator; (3) tissue reactions at the electrode/tissue interface; (4) general foreign body rejection phenomena; (5) perforation of the leads; and (6) excessive stress applied by sutures causing abrasion and stress cracking. Although silicone has been used widely, some years ago Pellethane (a segmented polyetherurethane-urea) has been introduced as an alternate lead insulator, chiefly because it can be extruded using additives into smooth and thin tubes. The additives (antioxidants), extrusion aids, and low molecular weight polymer chains (oligomers) together represent up to approximately 8% by weight of leachables, depending on the extraction medium. The in vivo degradation of Pellethane is biologic in nature and is most likely associated with the absorption and premeation of body fluids from the surrounding physiologic environment leading to stress cracking via the formation of microvoids. Thermally and biologically unstable biuret and allophonate groups in this polyurethane, exposure of the polymer to high extrusion temperatures, and stresses created within the polymer also play key roles in the degradation process. In the case of electrodes, some corrosion can occur even with noble metals and ions formed with the involvement of penetrating body fluids which may combine with the urethane and/or urea groups of the polyurethane, leading to its further degradation in vivo. The totality of the situation indicates a need for the development of a standard guideline for the uniform and consistent pre-clinical testing and evaluation of new materials and fabrication processes of implantable pacemaker leads. Such guidelines should take into consideration, among others, the physiological environment

  9. Spray forming lead strip. Final report

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, K.

    1996-04-10

    A cooperative research project was conducted between the Idaho National Engineering Laboratory (INEL) and Johnson Controls, Inc. (JCI) to adapt the INEL spray forming process to produce near-net-shape lead alloy strip. The emphasis of the work was to spray form lead strip samples at INEL, using a variety of spray conditions, for characterization at JCI. An existing glove box apparatus was modified at INEL to spray form lead. The main spray forming components were housed inside the glove box. They included a spray nozzle, tundish (crucible), substrate assembly, gas heater and furnaces to heat the nozzle and tundish. To spray form metal strip, liquid metal was pressure-fed at a controlled rate through a series of circular orifices that span the width of the nozzle. There the metal contacted high velocity, high temperature inert gas (nitrogen) which atomized the molten material into fine droplets, entrained the droplets in a directed flow, and deposited them onto glass plates that were swept through the spray plume to form strip samples. In-flight convection cooling of the droplets followed by conduction and convection cooling at the substrate resulted in rapid solidification of the deposit. During operation, the inside of the glove box was purged with an inert gas to limit the effects of in-flight oxidation of the particles and spray-formed strips, as well as to protect personnel from exposure to airborne lead particulate. Remote controls were used to start/stop the spray and control the speed and position of the substrate. In addition, substrate samples were loaded into the substrate translator manually using the gloved side ports of the box. In this way, the glove box remained closed during a series of spray trials, and was opened only when loading the crucible with a lead charge or when removing lead strip samples for shipment to JCI.

  10. The Number of Recalled Leads is Highly Predictive of Lead Failure: Results From the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS").

    Science.gov (United States)

    Kersten, Daniel J; Yi, Jinju; Feldman, Alyssa M; Brahmbhatt, Kunal; Asheld, Wilbur J; Germano, Joseph; Islam, Shahidul; Cohen, Todd J

    2016-12-01

    The purpose of this study was to determine if implantation of multiple recalled defibrillator leads is associated with an increased risk of lead failure. The authors of the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS") have previously reported a relationship between recalled lead status, lead failure, and patient mortality. This substudy analyzes the relationship in a smaller subset of patients who received more than one recalled lead. The specific effects of having one or more recalled leads have not been previously examined. This study analyzed lead failure and mortality of 3802 patients in PAIDLESS and compared outcomes with respect to the number of recalled leads received. PAIDLESS includes all patients at Winthrop University Hospital who underwent defibrillator lead implantation between February 1, 1996 and December 31, 2011. Patients with no recalled ICD leads, one recalled ICD lead, and two recalled ICD leads were compared using the Kaplan-Meier method and log-rank test. Sidak adjustment method was used to correct for multiple comparisons. All calculations were performed using SAS 9.4. P-values leads implanted during the trial period. There were 2400 leads (59%) in the no recalled leads category, 1620 leads (40%) in the one recalled lead category, and 58 leads (1%) in the two recalled leads category. No patient received more than two recalled leads. Of the leads categorized in the two recalled leads group, 12 experienced lead failures (21%), which was significantly higher (Pleads group (60 failures, 2.5%) and one recalled lead group (81 failures; 5%). Multivariable Cox's regression analysis found a total of six significant predictive variables for lead failure including the number of recalled leads (Pleads group). The number of recalled leads is highly predictive of lead failure. Lead-based multivariable Cox's regression analysis produced a total of six predictive variable categories for lead failure, one of which was the number

  11. Does Falling Smoking Lead to Rising Obesity?

    OpenAIRE

    Jonathan Gruber; Michael Frakes

    2005-01-01

    The strong negative correlation over time between smoking rates and obesity have led some to suggest that reduced smoking is increasing weight gain in the U.S.. This conclusion is supported by the findings of Chou et al. (2004), who conclude that higher cigarette prices lead to increased body weight. We investigate this issue and find no evidence that reduced smoking leads to weight gain. Using the cigarette tax rather than the cigarette price and controlling for non-linear time effects, we f...

  12. Lifetime modelling of lead acid batteries

    DEFF Research Database (Denmark)

    Bindner, H.; Cronin, T.; Lundsager, P.

    2005-01-01

    , therefore, lead to uncertainty in the viability of the system in the long term. This report details the work undertaken to investigate and develop two different battery life prediction methodologies withspecific reference to their use in hybrid renewable energy systems. Alongside this, results from battery...... been part of the European Union Benchmarking research project (ENK6-CT-2001-80576), funded by theEuropean Union, the United States and Australian governments together with other European states and other public and private financing bodies. The project has concentrated on lead acid batteries...

  13. Tool for Crimping Flexible Circuit Leads

    Science.gov (United States)

    Hulse, Aaron; Diftler, Myron A.

    2009-01-01

    A hand tool has been developed for crimping leads in flexible tails that are parts of some electronic circuits -- especially some sensor circuits. The tool is used to cut the tails to desired lengths and attach solder tabs to the leads. For tailoring small numbers of circuits for special applications, this hand tool is a less expensive alternative to a commercially available automated crimping tool. The crimping tool consists of an off-the-shelf hand crimping tool plus a specialized crimping insert designed specifically for the intended application.

  14. Lead Leached into Water from Select Plumbing Fixtures” Could Lead to Health Hazard

    Directory of Open Access Journals (Sweden)

    Ramsey Coles

    2014-01-01

    Full Text Available Background: Lead is an inert metal and is resistant to corrosion. It also increases tensile strength of many common materials in daily use. Lead was used during the Roman period to transport water (hence the name plumbing/plumber is common terminology even in the present day. Lead enters the biological system through the air, water, and dust. Fine particles of lead, having diameter less than 5 nm are directly absorbed by lungs. Inorganic lead is absorbed by the gastrointestinal tract, and organic lead is absorbed by the skin. Lead has long been known to be a toxic heavy metal and exposure is associated with many deleterious health effects. Still, lead remains a popular ingredient in products ranging from paint to batteries. The lead content in any given material is estimated using various methods. The least cumbersome method is found to be X-Ray Fluorescence technique (XRF. A portable XRF device was used in the present study. Aim: The main aim of this study to investigate whether lead is present in various commonly used plumbing materials. Material and Methods: All types of branded and commonly used pipes were gathered from a market in Bangalore and tested using the XRF machine. In order to evaluate to what extent lead from the pipes could leach into water, seven pipes were randomly selected and filled with Aquafina water (having undetectable level of lead for a 24 hour period. This water was tested at an NABL accredited laboratory in Bangalore, India for lead content. Result: It was determined that lead was present in many of the samples, at an unacceptable levels ranging from, well above the globally accepted level of 0.01 mg/L proof that lead was able to leach from the samples into water. Conclusions: As lead in drinking water represents a direct pathway for human exposure, the authors recommend that significant measures be taken to prevent use of lead in the plumbing industry for prevention of it’s deleterious effects. Authors have also

  15. Modeling of Blood Lead Levels in Astronauts Exposed to Lead from Microgravity-Accelerated Bone Loss

    Science.gov (United States)

    Garcia, H.; James, J.; Tsuji, J.

    2014-01-01

    Human exposure to lead has been associated with toxicity to multiple organ systems. Studies of various population groups with relatively low blood lead concentrations (bones, the adverse effects of lead correlate with the concentration of lead in the blood better than with that in the bones. NASA has found that prolonged exposure to microgravity during spaceflight results in a significant loss of bone minerals, the extent of which varies from individual to individual and from bone to bone, but generally averages about 0.5% per month. During such bone loss, lead that had been stored in bones would be released along with calcium. The effects on the concentration of lead in the blood (PbB) of various concentrations of lead in drinking water (PbW) and of lead released from bones due to accelerated osteoporosis in microgravity, as well as changes in exposure to environmental lead before, during, and after spaceflight were evaluated using a physiologically based pharmacokinetic (PBPK) model that incorporated exposure to environmental lead both on earth and in flight and included temporarily increased rates of osteoporosis during spaceflight.

  16. Pacemaker lead fracture without an increase in lead impedance caused by cardiac fibroma

    Directory of Open Access Journals (Sweden)

    Daisuke Sato

    2013-12-01

    Full Text Available We report the case of a 64-year-old man who had a permanent pacemaker with a unipolar silicone electrode positioned in the right ventricle in 1989 for sinus node dysfunction. On a routine checkup in June 2011, a 28-mm-diameter mass was discovered, which appeared to adhere to the tricuspid valve and the ventricular lead. The size of the mass did not change for the next 6 months, and the lead impedance was maintained at around 500–600 Ω. Because pacing failure was observed in January 2012, he underwent an urgent pacemaker check; however, the lead impedance was found not to have increased greatly (689 Ω. Nevertheless, the pacemaker lead was noted to be fractured at the tricuspid level. His echocardiogram showed new severe tricuspid regurgitation and a floating mass around the lead. We extracted the fractured lead, enucleated the tumor, replaced the tricuspid valve, and placed an epicardial lead. Macroscopic examination revealed that the tumor surrounded the fractured lead and covered the stump. Pathological examination revealed that the tumor was composed of fibrous connective tissue. We presumed that electric current continued to flow through the stump of the fractured unipolar lead to the generator, and this might have caused the limited increase in lead impedance.

  17. Lead level in seminal plasma may affect semen quality for men without occupational exposure to lead.

    Science.gov (United States)

    Wu, Hsien-Ming; Lin-Tan, Dan-Tzu; Wang, Mei-Li; Huang, Hong-Yuan; Lee, Chyi-Long; Wang, Hsin-Shih; Soong, Yung-Kuei; Lin, Ja-Liang

    2012-11-08

    Infertility affects approximately 10-15% of reproductive-age couples. Poor semen quality contributes to about 25% of infertile cases. Resulting from the direct effect on testicular function or hormonal alterations, heavy metals exposure has been related to impaired semen quality. The objective of this study was to assess the level of lead in the seminal plasma in men without occupational exposure to lead, and to determine the relationship between semen quality and lead concentration in the semen. This is a prospective and nonrandomized clinical study conducted in University infertility clinic and academic research laboratory. Three hundred and forty-one male partners of infertile couples undergoing infertility evaluation and management were recruited to the study. Semen samples collected for the analyses of semen quality were also used for the measurement of lead concentrations. Semen samples were evaluated according to the WHO standards. All subjects were married and from infertile couples without occupational exposure to lead. There is a significant inverse correlation between the lead concentration in seminal plasma and sperm count. A higher semen lead concentration was correlated with lower sperm count, but not with semen volume, sperm motility or sperm morphology as assessed by simple linear regression. We found that semen lead concentration was significantly higher among the patients with lower sperm count. To our knowledge, this is the first study to demonstrate that a high level of lead accumulation in semen may reduce the sperm count contributing to infertility of men without occupational exposure to lead.

  18. Lead sources to California sea otters: Industrial inputs circumvent natural lead biodepletion mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.R.; Flegal, A.R. (Univ. of California, Santa Cruz (United States)); Niemeyer, S. (Lawrence Livermore National Lab., CA (United States))

    1992-04-01

    Lead levels (as Pb/Ca atom ratios) and stable isotopic compositions were measured in teeth of preindustrial and contemporary California sea otters (Enhydra lutris) to determine if postindustrial changes had occurred in the magnitude and source of accumulated lead. Lead/calcium atom ratios in teeth of some contemporary animals were significantly elevated and compared to level in other contemporary and preindustrial otters. The isotopic ratios revealed a change in the sources of accumulated leads, from natural continental-derived lead in the preindustrial animals ({sup 207}Pb/{sup 206}Pb = 0.820 {plus minus} 0.002) to industrial sources dominated by aerosol lead in the contemporary otters ({sup 207}Pb/{sup 206}Pb = 0.853), who contained lead derived from an industrial waste lead deposit in Monterey Harbor. These data establish distinguishable sources of lead assimilated by sea otters, and indicate that elevated exposures to some animals circumvented the natural biodepletion of lead through marine trophic pathways.

  19. Lead Contents and Distribution Characteristics of Soils and Vegetables Around an Abandoned Lead Smeltery

    Directory of Open Access Journals (Sweden)

    ZOU Tian-sen

    2016-07-01

    Full Text Available In order to disclose the degree and scope of lead pollution of the abandoned lead smeltery, 102 surface soil samples and 69 vegetables samples were collected by using the method of fan-shaped sampling points around an abandoned lead smeltery in Hubei Province. The lead contents of soils and vegetables were detected by graphite furnace atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry, respectively, and the lead spatial distribution was analyzed. The results showed that the geometric mean of lead contents in soils around the abandoned lead smeltery was 39.8 mg·kg-1 and exceeded the soil background value of Hubei Province(26.7 mg·kg-1. The mean value of geo-accumulation indexes of lead contents in soil was 0.09, and 36.4% of them exceeded zero. The geo-accumulation indexes of sampling distance of 500, 1000 m and 1500 m from the smeltery were 2.11, 0.61 and 0.33, respectively, while the values of sampling distances of more than 2000 m were all less than zero. 24.0%、36.0% and 6.3% of the lead contents exceeded the standard value of limited standards of contaminants in vagetables for cabbage, radish and green onion samples, respectively. The soils and vegetables around the abandonded lead smeltery within 500 m were contaminated seriously. The degree of lead pollution in soils was mild or moderate within 500 m to 2000 m, and the maximum scope in cabbage, radish and green onion was polluted within 500~1000, 1000~1500 m and 500~1000 m, respectively. Lead pollution in vegetables around the abandonded lead smeltery presented obvious characteristics of high pollution and enrichment.

  20. Failure of implantable cardioverter-defibrillator leads: a matter of lead size?

    Science.gov (United States)

    Rordorf, Roberto; Poggio, Luca; Savastano, Simone; Vicentini, Alessandro; Petracci, Barbara; Chieffo, Enrico; Klersy, Catherine; Landolina, Maurizio

    2013-02-01

    Small-diameter implantable cardioverter-defibrillator (ICD) Sprint Fidelis and Riata leads have been recalled owing to an increased risk of lead failure, thus arousing the suspicion that lead size might be a critical issue. To compare the incidence of failure of small-diameter (≤8 F) and standard-diameter (>8 F) ICD leads implanted in a single center. From January 2003 to December 2010, 190 Sprint Fidelis, 182 Riata/Riata ST, 99 Optim (Riata Optim/Durata), and 419 standard-diameter leads were implanted in our center. During a median follow-up of 33 months, the overall failure rate was 6.3%. Follow-up duration was similar for Sprint Fidelis, Riata, and standard-diameter leads but shorter for the Optim group. The failure rate was significantly higher in Sprint Fidelis leads than in both standard-diameter (4.8%/year vs 0.8%/year; Pleads. The incidence of lead failure in Riata/Riata ST leads proved significantly higher than in standard-diameter leads (2.6%/year vs 0.8%/year; P = .001). No cases of lead failure were recorded in the Optim group. On multivariable analyses, small-diameter (hazard ratio [HR] 5.03, 2.53-10.01, Pleads and agelead failure. Compared with standard-diameter leads, both Sprint Fidelis and Riata/Riata ST small-diameter ICD leads are at an increased risk of failure, although the incidence of events is significantly lower in the Riata than in the Sprint Fidelis group. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  1. Soil is an important pathway of human lead exposure.

    OpenAIRE

    Mielke, H W; Reagan, P L

    1998-01-01

    This review shows the equal or greater importance of leaded gasoline-contaminated dust compared to lead-based paint to the child lead problem, and that soil lead, resulting from leaded gasoline and pulverized lead-based paint, is at least or more important than lead-based paint (intact and not pulverized) as a pathway of human lead exposure. Because lead-based paint is a high-dose source, the biologically relevant dosage is similar to lead in soil. Both lead-based paint and soil lead are asso...

  2. Can climate change lead to gap formation ?

    NARCIS (Netherlands)

    Berestycki, Henri; Desvillettes, Laurent; Diekmann, Odo

    2014-01-01

    Consider a situation where spatial heterogeneity leads to a cline, a gradual transition in dominance of two competing species. We first prove, in the context of a simplified competition–diffusion model, that there exists a stationary solution showing that the two species coexist in a transition

  3. Lead Paint Test Kits Workshop: Summary Report

    Science.gov (United States)

    The U.S. Environmental Protection Agency's (EPA) Office of Research and Development (ORD) designed and conducted the Lead Paint Test Kits Workshop on October 19 and 20, 2006, at the Environmental Protection Agency's Research Triangle Park, NC campus. The workshop was conducted as...

  4. 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...

  5. Industrial Dynamics Beyond the Lead Firms

    DEFF Research Database (Denmark)

    Haakonsson, Stine Jessen; Slepniov, Dmitrij

    2013-01-01

    Since the turn of the millennium, China has developed into a core location for the wind energy industry and is today the largest market for wind turbines. These developments have caught attention among scholars. However, most research is on the development of the market and the lead firm strategi...

  6. CHILDHOOD RISK ESTIMATION OF LEAD METAL POISOINING ...

    African Journals Online (AJOL)

    Dr Osondu

    2011-10-28

    Oct 28, 2011 ... The childhood lead (Pb) poisoning risk from consumption and risk model data of snail meat from Pb metal contaminated sites of entrance (control), storage dump, dried effluent and waste dump at an abandoned battery factory, in Niger Delta, Nigeria were estimated. Results implicated snail meat from.

  7. Proton beam modification of lead white pigments

    Energy Technology Data Exchange (ETDEWEB)

    Beck, L., E-mail: lucile.beck@cea.fr [CEA, DEN, Service de Recherches de Métallurgie Physique, Laboratoire JANNUS, 91191 Gif-sur-Yvette (France); Centre de recherche et de restauration des musées de France (C2RMF), Palais du Louvre – Porte des Lions, 14 quai François Mitterrand, 75001 Paris (France); Gutiérrez, P.C. [Centre de recherche et de restauration des musées de France (C2RMF), Palais du Louvre – Porte des Lions, 14 quai François Mitterrand, 75001 Paris (France); Centro de Micro-Análisis de Materiales (CMAM), Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid (Spain); Miserque, F. [CEA, DEN, DPC/SCCME/LECA, 91191 Gif-sur-Yvette (France); Thomé, L. [Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), CNRS/IN2P3 et Université Paris-Sud, Bât. 108, 91405 Orsay (France)

    2013-07-15

    Pigments and paint materials are known to be sensitive to particle irradiation. Occasionally, the analysis of paintings by PIXE can induce a slight or dark stain depending on the experimental conditions (beam current, dose, particle energy). In order to understand this discoloration, we have irradiated various types of art white pigments – lead white (hydrocerussite and basic lead sulfate), gypsum, calcite, zinc oxide and titanium oxide – with an external 3 MeV proton micro-beam commonly used for PIXE experiments. We have observed various sensitivities depending on the pigment. No visible change occurs for calcite and titanium oxide, whereas lead white pigments are very sensitive. For the majority of the studied compounds, the discoloration is proportional to the beam current and charge. The damage induced by proton beam irradiation in lead white pigments was studied by micro-Raman and XPS spectroscopies. Structural modifications and dehydration were detected. Damage recovery was investigated by thermal treatment and UV-light irradiation. The discoloration disappeared after one week of UV illumination, showing that PIXE experiments could be safely undertaken for pigments and paintings.

  8. Leading in a Culture of Change.

    Science.gov (United States)

    Fullan, Michael

    The more complex society gets, the more sophisticated leadership must become. This book is about how leaders can focus on certain key change themes that will allow them to lead effectively under messy conditions. Chapter 1 identifies theoretical reasons why change occurs as it does. They include moral purpose, understanding change, developing…

  9. 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…

  10. Acute hyperventilation leading to hypocalcaemia during spinal ...

    African Journals Online (AJOL)

    Adele

    semi open systems (Mapleson A to F) with appropriate flow or circle with absorber excluded and a low flow of gases would have achieved it.8 The resulting decrease in pH leads to a normalization of ionized calcium level. However, we were not able to use it because of the difficulty encountered in providing a tight mask ...

  11. Does Education Lead to Higher Generalized Trust?

    DEFF Research Database (Denmark)

    Charron, Nicholas; Rothstein, Bo

    2016-01-01

    to ‘trust others'. We hypothesize that higher levels of education will lead to higher social trust in individuals, given that the context (country or regions within countries) in which they reside has a sufficiently impartial and non-corrupt institutional setting. However, the positive effect of education...

  12. When municipalities lead co-production

    DEFF Research Database (Denmark)

    Tortzen, Anne

    2015-01-01

    This article explores the role played by municipalities as ‘key leaders’ in co-production processes initiated by local governments. The aim is to produce new insights into the challenges faced by public agencies leading co-production processes in practice. Drawing on an analytical framework derived...

  13. Do Policy Networks lead to Network Governing?

    DEFF Research Database (Denmark)

    Damgaard, Bodil

    This paper challenges the notion that creation of local policy networks necessarily leads to network governing. Through actor-centred case studies in the area of municipally implemented employment policy in Denmark it was found that the local governing mode is determined mainly by the municipality...

  14. Selected Bibliography on Lead Poisoning in Children.

    Science.gov (United States)

    Lin-Fu, Jane S., Comp.

    This comprehensive bibliography was prepared in response to the growing interest in the problem of childhood lead poisoning. Most of the papers noted are from the pediatric literature and include only those published in English. A limited number of papers on experiments in laboratory animals are cited. Documents are grouped under several general…

  15. Child Care Lead Poisoning Prevention. Training Curriculum.

    Science.gov (United States)

    California Dept. of Health Services, Oakland. Childhood Lead Poisoning Prevention Branch.

    In an effort to address young children's substantial risk for exposure to lead in out-of-home child care programs, outreach and training were developed for child care providers. This workshop curriculum consists of training activities and materials appropriate for child care providers in centers or homes for the purpose of educating them about the…

  16. Childhood Lead Poisoning: Resources for Prevention.

    Science.gov (United States)

    Alliance to End Childhood Lead Poisoning, Washington, DC.

    The current approach to dealing with childhood lead poisoning has led to repeated diagnoses of poisoning because such children are treated and then returned to their hazardous environments. This handbook, the third in a three-volume set, provides examples of specific materials currently or recently used in ongoing state and local childhood lead…

  17. Lead Poisoning at an Indoor Firing Range.

    Science.gov (United States)

    Kang, Kyung Wook; Park, Won Ju

    2017-10-01

    In March 2014, a 39-year-old Korean male presented with a 6-month history of various nonspecific symptoms including dizziness, fatigue, asthenia, irritability, elevated blood pressure, palpitation, eyestrain, and tinnitus. His occupational history revealed that he had been working as an indoor firing range manager for 13 months; therefore, he was subjected to a blood lead level (BLL) test. The test results showed a BLL of 64 μg/dL; hence, he was diagnosed with lead poisoning and immediately withdrawn from work. As evident from the workplace environmental monitoring, the level of lead exposure in the air exceeded its limit (0.015-0.387 mg/m³). He received chelation treatment with calcium-disodium ethylenediaminetetraacetic acid (1 g/day) for 5 days without any adverse effects. In the follow-up results after 2 months, the BLL had decreased to 9.7 μg/dL and the symptoms resolved. This report represents the first occupational case of lead poisoning in firing ranges in Korea, and this necessitates institutional management to prevent the recurrence of poisoning through this route. Workplace environmental monitoring should be implemented for indoor firing ranges, and the workers should undergo regularly scheduled special health examinations. In clinical practice, it is essential to question the patient about his occupational history. © 2017 The Korean Academy of Medical Sciences.

  18. 31 CFR 800.218 - Lead agency.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Lead agency. 800.218 Section 800.218 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF INVESTMENT SECURITY, DEPARTMENT OF THE TREASURY REGULATIONS PERTAINING TO MERGERS, ACQUISITIONS, AND TAKEOVERS BY...

  19. Leading-Edge Vortex lifts swifts

    NARCIS (Netherlands)

    Videler, JJ; Stamhuis, EJ; Povel, GDE

    2004-01-01

    The current understanding of how birds fly must be revised, because birds use their hand-wings in an unconventional way to generate lift and drag. Physical models of a common swift wing in gliding posture with a 60degrees sweep of the sharp hand-wing leading edge were tested in a water tunnel.

  20. Leading and following with a virtual trainer

    NARCIS (Netherlands)

    Reidsma, Dennis; Dehling, Eike; van Welbergen, H.; Zwiers, Jakob; Nijholt, Antinus; England, D.; El Rhalibi, A.; Cheok, A.D.

    2011-01-01

    This paper describes experiments with a virtual fitness trainer capable of mutually coordinated interaction. The virtual human co-exercises along with the user, leading as well as following in tempo, to motivate the user and to influence the speed with which the user performs the exercises. In a

  1. Blood lead concentration after a shotgun accident.

    Science.gov (United States)

    Gerhardsson, Lars; Dahlin, Lars; Knebel, Richard; Schütz, Andrejs

    2002-01-01

    In an accidental shooting, a man in his late forties was hit in his left shoulder region by about 60 lead pellets from a shotgun. He had injuries to the vessels, the clavicle, muscles, and nerves, with total paralysis of the left arm due to axonal injury. After several surgical revisions and temporary cover with split skin, reconstructive surgery was carried out 54 days after the accident. The brachial plexus was swollen, but the continuity of the nerve trunks was not broken (no neuroma present). We determined the blood lead (BPb) concentration during a follow-up period of 12 months. The BPb concentration increased considerably during the first months. Although 30 lead pellets were removed during the reconstructive surgery, the BPb concentration continued to rise, and reached a peak of 62 microg/dL (3.0 micromol/L) on day 81. Thereafter it started to decline. Twelve months after the accident, BPb had leveled off at about 30 microg/dL. At that time, muscle and sensory functions had partially recovered. The BPb concentration exceeded 30 microg/dL for 9 months, which may have influenced the recovery rate of nerve function. Subjects with a large number of lead pellets or fragments embedded in the body after shooting accidents should be followed for many years by regular determinations of BPb. To obtain a more stable basis for risk assessment, the BPb concentrations should be corrected for variations in the subject's hemoglobin concentration or erythrocyte volume fraction.

  2. Lead inhibition of enzyme synthesis in soil.

    Science.gov (United States)

    Cole, M A

    1977-02-01

    Addition of 2 mg of Pb2+/g of soil concident with or after amendment with starch or maltose resulted in 75 and 50% decreases in net synthesis of amylase and alpha-glucosidase, respectively. Invertase synthesis in sucrose-amended soil was transiently reduced after Pb2+ addition. Amylase activity was several times less sensitive to Pb2+ inhibition than was enzyme synthesis. In most cases, the rate of enzyme synthesis returned to control (Pb2+) values 24 to 48 h after the addition of Pb. The decrease in amylase synthesis was paralleled by a decrease in the number of Pb-sensitive, amylase-producing bacteria, whereas recovery of synthesis was associated with an increase in the number of amylase-producing bacteria. The degree of inhibition of enzyme synthesis was related to the quantity of Pb added and to the specific form of lead. PbSO4 decreased amylase synthesis at concentrations of 10.2 mg of Pb2+/g of soil or more, whereas PbO did not inhibit amylase synthesis at 13 mg of Pb2+/g of soil. Lead acetate, PbCl2, and PbS reduced amylase synthesis at total Pb2+ concentrations of 0.45 mg of Pb2+/g of soil or higher. The results indicated that lead is a potent but somewhat selective inhibitor of enzyme synthesis in soil, and that highly insoluble lead compounds, such as PbS, may be potent modifiers of soil biological activity.

  3. 29 CFR 1910.1025 - Lead.

    Science.gov (United States)

    2010-07-01

    ... air. (ii) Shoveling, dry or wet sweeping, and brushing may be used only where vacuuming or other... physical examination, with particular attention to teeth, gums, hematologic, gastrointestinal, renal... lungs and upper respiratory tract. Inhalation of airborne lead is generally the most important...

  4. Relationships between blood lead, blood pressure, serum

    African Journals Online (AJOL)

    Dr Gatsing

    also associated significantly with serum cholesterol for non-smokers (r = + 0.114) and body mass index for non–smoker (r = + 0.110) at p≤0.10. Systolic blood .... that they were lead free. Consequently, each material was rinsed with 5 ml ..... for subjects from some cities in southwest. Nigeria (Adeniyi and Anetor, 1999). The.

  5. Leading-Edge Learning: Two Views.

    Science.gov (United States)

    Abernathy, Donna J.

    1999-01-01

    Peter Senge and Jack Welch share thoughts about what it means to learn and lead into the next century. Senge urges leaders to be aware of the economic and the natural environment. Welch asserts that an organization's ability to learn and translate learning into action is the ultimate competitive advantage. (JOW)

  6. Research Leads: Current Practice, Future Prospects

    Science.gov (United States)

    Riggall, Anna; Singer, Rachel

    2015-01-01

    This report was conceived as one of three publications that collectively provide a commentary on research awareness and research use within schools in England. This third report in the series presents findings from a small-scale, detailed study of teachers who are operating as their school's Research Lead. The small scale of the study is…

  7. Lead free solder mechanics and reliability

    CERN Document Server

    Pang, John Hock Lye

    2012-01-01

    Lead-free solders are used extensively as interconnection materials in electronic assemblies and play a critical role in the global semiconductor packaging and electronics manufacturing industry. Electronic products such as smart phones, notebooks and high performance computers rely on lead-free solder joints to connect IC chip components to printed circuit boards. Lead Free Solder: Mechanics and Reliability provides in-depth design knowledge on lead-free solder elastic-plastic-creep and strain-rate dependent deformation behavior and its application in failure assessment of solder joint reliability. It includes coverage of advanced mechanics of materials theory and experiments, mechanical properties of solder and solder joint specimens, constitutive models for solder deformation behavior; numerical modeling and simulation of solder joint failure subject to thermal cycling, mechanical bending fatigue, vibration fatigue and board-level drop impact tests. This book also: Discusses the mechanical prope...

  8. Performance of lead-free versus lead-based hunting ammunition in ballistic soap.

    Directory of Open Access Journals (Sweden)

    Felix Gremse

    Full Text Available BACKGROUND: Lead-free hunting bullets are an alternative to lead-containing bullets which cause health risks for humans and endangered scavenging raptors through lead ingestion. However, doubts concerning the effectiveness of lead-free hunting bullets hinder the wide-spread acceptance in the hunting and wildlife management community. METHODS: We performed terminal ballistic experiments under standardized conditions with ballistic soap as surrogate for game animal tissue to characterize dimensionally stable, partially fragmenting, and deforming lead-free bullets and one commonly used lead-containing bullet. The permanent cavities created in soap blocks are used as a measure for the potential wound damage. The soap blocks were imaged using computed tomography to assess the volume and shape of the cavity and the number of fragments. Shots were performed at different impact speeds, covering a realistic shooting range. Using 3D image segmentation, cavity volume, metal fragment count, deflection angle, and depth of maximum damage were determined. Shots were repeated to investigate the reproducibility of ballistic soap experiments. RESULTS: All bullets showed an increasing cavity volume with increasing deposited energy. The dimensionally stable and fragmenting lead-free bullets achieved a constant conversion ratio while the deforming copper and lead-containing bullets showed a ratio, which increases linearly with the total deposited energy. The lead-containing bullet created hundreds of fragments and significantly more fragments than the lead-free bullets. The deflection angle was significantly higher for the dimensionally stable bullet due to its tumbling behavior and was similarly low for the other bullets. The deforming bullets achieved higher reproducibility than the fragmenting and dimensionally stable bullets. CONCLUSION: The deforming lead-free bullet closely resembled the deforming lead-containing bullet in terms of energy conversion

  9. Antiviral lead compounds from marine sponges.

    Science.gov (United States)

    Sagar, Sunil; Kaur, Mandeep; Minneman, Kenneth P

    2010-10-11

    Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hoped to be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed.

  10. Antiviral Lead Compounds from Marine Sponges

    Directory of Open Access Journals (Sweden)

    Kenneth P. Minneman

    2010-10-01

    Full Text Available Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV and herpes simplex virus (HSV. The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed.

  11. Antiviral lead compounds from marine sponges

    KAUST Repository

    Sagar, Sunil

    2010-10-11

    Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed. 2010 by the authors; licensee MDPI.

  12. [Lead intoxication in shipscrapping employees in Taiwan].

    Science.gov (United States)

    Chiang, H C; Chang, P Y

    1989-05-01

    The shipscrapping industry in Taiwan is located at Kaohsiung harbor. The scrapping yard at Kaohsiung can be divided into the "Da-Jen" area and the "Da-Lin" area, including 23 and 13 docks respectively. About 5000-8000 dock workers are employed in the yard. Because shipscrapping has been considered to be a "temporary" industry by the secondary metal dealers, so the dealers did not well equip and offer the appropriate safety and health programs for the industry. Of those who work on the docks the metal burners are those most continuously exposed to substantial amounts of inorganic lead and other unidentified metals along with health stresses such as noise, asbestos, explosions and accidents. In this study, 140 oxyacetylene torch metal burners (83 working on scrapping ships and 57 working at the yard) and 21 dock workers without direct lead exposure as the control group were included. The mean values of blood lead and urine lead were 63.22 +/- 22.04 micrograms/d1 and 122.15 +/- 44.10 micrograms/1 for metal burners on the ship, and 65.25 +/- 37.11 micrograms/d1 and 101.54 +/- 37.11 micrograms/1 for the metal burners at the yard, values for the control group were 37.24 +/- 20.63 micrograms/d1 and 67.62 +/- 38.39 micrograms/1 respectively. The subjective symptoms mainly were fatigue, numbness over extremities, headache and dizzness. There were 49 metal burners, 35% of the total burners examined in this study, whose blood lead exceeded 80 micrograms/d1 with more than 2 suspicious intoxication symptoms. The precautions in terms of environmental mornitoring, medical surveillance and engineering control should be taken.

  13. Investigation and Evaluation of Children's Blood Lead Levels around a Lead Battery Factory and Influencing Factors.

    Science.gov (United States)

    Zhang, Feng; Liu, Yang; Zhang, Hengdong; Ban, Yonghong; Wang, Jianfeng; Liu, Jian; Zhong, Lixing; Chen, Xianwen; Zhu, Baoli

    2016-05-28

    Lead pollution incidents have occurred frequently in mainland China, which has caused many lead poisoning incidents. This paper took a battery recycling factory as the subject, and focused on measuring the blood lead levels of environmental samples and all the children living around the factory, and analyzed the relationship between them. We collected blood samples from the surrounding residential area, as well as soil, water, vegetables. The atomic absorption method was applied to measure the lead content in these samples. The basic information of the generation procedure, operation type, habit and personal protect equipment was collected by an occupational hygiene investigation. Blood lead levels in 43.12% of the subjects exceeded 100 μg/L. The 50th and the 95th percentiles were 89 μg/L and 232 μg/L for blood lead levels in children, respectively, and the geometric mean was 94 μg/L. Children were stratified into groups by age, gender, parents' occupation, distance and direction from the recycling plant. The difference of blood lead levels between groups was significant (p factory, the higher the value of BLL and lead levels in vegetable and environment samples. The lead level in the environmental samples was higher downwind of the recycling plant.

  14. [Lead exposure of people living in a lead high exposure area from local diet].

    Science.gov (United States)

    Zhou, Yong; He, Liping; Huang, Xiao; He, Junshan

    2011-11-01

    To study the lead exposure of people living in a lead high exposure area from local diet, and to assess its health risks. Thirty five subjects were selected by random from a mining area and another 30 subjects were selected from a non-polluted area. The exposure of lead was estimated by the content of lead in drinking water and vegetables, and health risks was estimated by the levels of lead in blood and urine. The content of lead in drinking water and vegetables in the mining area was 20.6 microg/L and 1.61mg/kg (geometric mean) respectively, which were higher than that in the unpolluted area (6.0 microg/L and 0.56 mg/kg, geometric mean) (P area from diet was 16.88 microg/kg and 16.09 microg/kg respectively, which was higher than that in the unpolluted area (P 0.05). Blood lead and urine lead of inhabitants in the mining-area were higher than those in the unpolluted area. The health risks for male and female inhabitants in the mining area were 4.73 and 4.51. The health risks of lead exposure caused by diet (drinking water and food) were relatively high in the mining area.

  15. Environmental lead and childhood blood lead levels in US children: NHANES, 1999-2006.

    Science.gov (United States)

    Benson, Stacey M; Talbott, Evelyn O; Brink, LuAnn L; Wu, Candace; Sharma, Ravi K; Marsh, Gary M

    2017-03-04

    Although blood lead levels in the United States have fallen dramatically since 1980, there remain subgroups of children with high blood lead levels. We assessed the relationship between environmental lead sources and blood lead levels in children ages 1 to 5 years from the National Health and Nutrition Examination Survey (NHANES), 1999-2006. Modeled ambient air lead levels and industrial lead releases at the census-tract level were assigned to each child's residence with adjustment for confounding factors. Of 3,223 children, 272 (8.4%) had blood lead levels ≥ 5 ug/dL. Industrial releases (2,252 vs 1,696 lbs/mi 2 ) and ambient air lead levels (2.28 vs 1.75 ng/m 3 ) were greater in exposed versus unexposed children. For every 10,000 lb/mi 2 increase in inverse distance squared weighted exposure, there was a 1.13% increase (95% CI: 0.45%, 1.81%) in blood lead (p = .001).

  16. The impact of the new 36 V lead-acid battery systems on lead consumption

    Science.gov (United States)

    Prengaman, R. David

    The production of vehicles utilizing 36 V battery systems has begun with the introduction of the Toyota Crown. Other vehicles with 36 V batteries are in the near horizon. These vehicles may contain single or dual battery systems. These vehicles will most likely contain valve-regulated lead-acid (VRLA) batteries. The battery systems developed to date utilize significantly more lead than conventional 12 V batteries. This paper will evaluate the different proposed 36 V battery systems and estimate the lead requirements for each of the competing systems. It will also project the penetration of and resultant increased lead usage of these new batteries into the future.

  17. Riata implantable cardioverter-defibrillator lead failure: analysis of explanted leads with a unique insulation defect.

    Science.gov (United States)

    Hauser, Robert G; McGriff, Deepa; Retel, Linda Kallinen

    2012-05-01

    The Riata family of implantable cardioverter-defibrillator leads (St Jude Medical, Sylmar, CA) appears prone to a unique failure mechanism whereby the conductor cables wear through the silicone insulation from inside-out and are seen outside the lead body (externalized conductors). To assess the extent of Riata lead damage associated with inside-out insulation defects and their clinical consequences. In September 2011, we searched the U.S. Food and Drug Administration's Manufacturers and User Defined Experience medical device database for reports describing Riata lead failures that had been analyzed by the manufacturer. The Manufacturers and User Defined Experience search identified 105 leads that had inside-out insulation defects. Eight-French single-coil Riata leads accounted for a higher-than-expected proportion (25.7%) of the leads with this defect. A total of 226 insulation defects were found in the 105 leads (2.2 defects per lead), including 143 inside-out defects (1.4 defects per lead). The most common location of insulation defects was distal to the proximal coil (n = 108). Twenty-eight leads (26.7%) had inside-out insulation defects underneath the shocking coils. Of 43 leads whose cables were assessed for the integrity of the ethylene-tetrafluoroethylene cable coating, 22 (51.2%) were found to be abraded, exposing the conductor surfaces. On X-ray radiography or fluoroscopy, 7 leads were found to have externalized cables; 2 of these leads had no electrical abnormalities, while 4 exhibited noise or increased impedance. Inappropriate shocks were experienced by 31 of the 105 patients (29.5%). Riata leads that have inside-out insulation defects often have multiple defects, including additional inside-out abrasions along the body of the lead and beneath the shocking coils. Eight-French single-coil Riata models may be more prone to externalized cables than are dual-coil and 7-F designs. Externalized cables are but one manifestation of interior insulation damage

  18. Preparation, Structural, Electrical, and Ferroelectric Properties of Lead Niobate–Lead Zirconate–Lead Titanate Ternary System

    Directory of Open Access Journals (Sweden)

    Rashmi Gupta

    2015-01-01

    Full Text Available A ternary system of lead niobate–lead zirconate–lead titanate with composition xPN–yPZ–(x-yPT where x=0.5 and y=0.15, 0.25, and 0.35 known as PNZT has been prepared by conventional mixed oxide route at a temperature of 1100°C. The formation of the perovskite phase was established by X-ray diffraction analysis. The surface morphology studied by scanning electron microscopy shows the formation of fairly dense grains and elemental composition was confirmed by energy dispersive X-ray analysis. Dielectric properties like dielectric constant and dielectric loss (ε′ and tan⁡δ indicate poly-dispersive nature of the material. The temperature dependent dielectric constant (ε′ curve indicates relaxor behaviour with two dielectric anomalies. The poly-dispersive nature of the material was analysed by Cole-Cole plots. The activation energy follows the Arrhenius law and is found to decrease with increasing frequency for each composition. The frequency dependence of ac conductivity follows the universal power law. The ac conductivity analysis suggests that hopping of charge carriers among the localized sites is responsible for electrical conduction. The ferroelectric studies reveal that these ternary systems are soft ferroelectric.

  19. Blood Lead Levels in Children and Environmental Lead Contamination in Miami Inner City, Florida

    Directory of Open Access Journals (Sweden)

    Theophile Niyonsenga

    2006-09-01

    Full Text Available Studies have shown that the environmental conditions of the home are important predictors of health, especially in low-income communities. Understanding the relationship between the environment and health is crucial in the management of certain diseases. One health outcome related to the home environment among urban, minority, and low-income children is childhood lead poisoning. The most common sources of lead exposure for children are lead paint in older, dilapidated housing and contaminated dust and soil produced by accumulated residue of leaded gasoline. Blood lead levels (BLL as low as 10 μg/dL in children are associated with impaired cognitive function, behavior difficulties, and reduced intelligence. Recently, it is suggested that the standard for intervention be lowered to BLL of 5 μg /dl. The objectives of our report were to assess the prevalence of lead poisoning among children under six years of age and to quantify and test the correlations between BLL in children and lead exposure levels in their environment. This cross-sectional analysis was restricted to 75 children under six years of age who lived in 6 zip code areas of inner city Miami. These locations exhibited unacceptably high levels of lead dust and soil in areas where children live and play. Using the 5 μg/dL as the cutoff point, the prevalence of lead poisoning among the study sample was 13.33%. The study revealed that lead levels in floor dust and window sill samples were positively and significantly correlated with BLL among children (p < 0.05. However, the correlations between BLL and the soil, air, and water samples were not significant. Based on this pilot study, a more comprehensive environmental study in surrounding inner city areas is warranted. Parental education on proper housecleaning techniques may also benefit those living in the high lead-exposed communities of inner city Miami.

  20. Australian atmospheric lead deposition reconstructed using lead concentrations and isotopic compositions of archival lichen and fungi.

    Science.gov (United States)

    Wu, Liqin; Taylor, Mark Patrick; Handley, Heather K; Wu, Michael

    2016-01-01

    Lead concentrations and their isotopic compositions were measured in lichen genera Cladonia and Usnea and fungi genus Trametes from the Greater Sydney region (New South Wales, Australia) that had been collected and archived over the past 120 years. The median lead contents were elevated in lichens and fungi prior to the introduction of leaded petrol (Cladonia 12.5 mg/kg; Usnea 15.6 mg/kg; Trametes 1.85 mg/kg) corresponding to early industrial development. During the use of leaded petrol for automobiles in Australia from 1932 to 2002, total median lead concentrations rose: Cladonia 18.8 mg/kg; Usnea 21.5 mg/kg; Trametes 4.3 mg/kg. Following the cessation of leaded petrol use, median total lead concentrations decreased sharply in the 2000s: Cladonia 4.8 mg/kg; Usnea 1.7 mg/kg. The lichen and fungi isotopic compositions reveal a significant decrease in (206)Pb/(207)Pb values from the end of 19th century to the 1970s. The following decades were characterised by lower allowable levels of lead additive in fuel and the introduction of unleaded petrol in 1985. The environmental response to these regulatory changes was that lichen and fungi (206)Pb/(207)Pb values increased, particularly from 1995 onwards. Although the lead isotope ratios of lichens continued to increase in the 2000s they do not return to pre-leaded petrol values. This demonstrates that historic leaded petrol emissions, inter alia other sources, remain a persistent source of anthropogenic contamination in the Greater Sydney region. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. [Acute lead poisoning: a singular case of hemolytic anemia and lead colic].

    Science.gov (United States)

    Corradi, M; Goldoni, M; Sabbadini, F; Mutti, A

    2011-01-01

    Acute lead poisoning due to food intake is exceptional in adults and often associated with mental illness to describe a case report of acute lead intoxication with haemolytic anemia and lead colic. A 41-year old male patient was admitted to hospital for abdominal pain and persistent constipation. Abdominal X-ray showed a radiopaque mass in the caecum and progressive anaemia was observed The patient was discharged with a diagnosis of bowel obstruction. Due to persistence of the symptoms he was again hospitalized; abdominal X-ray showed diffuse radiopaque particles in the colon and haemoglobin (hb) had dropped to 8.7 g/dl. Blood levels of lead and zinc protoporphryin were 106.7 microg/dl and 6.6 microg/gHb, respectively. The timely start of chelating therapy led to a rapid return to normal peripheral blood counts and a decline in blood lead levels. Although acute lead poisoning due to intake with food is exceptional in adults and often associated with mental illness, in this case, it was not possible to clarify the route and vehicle of ingestion of the toxic. Lead body burden was shown as a caecal mass, probably as a result of ingesting a single bolus of lead dust which, considering the size and density of the mass, was estimated as weighing several grammes. This acute lead intake induced an acute haemolysis due to enhanced fragility of the erythrocyte membrane. In the course of acute lead intoxication, the critical organ is not the bone marrow, but rather the red blood cell, leading to haemolysis and anaemia.

  2. Sources, symptoms and characteristics of childhood lead poisoning: experience from a lead specialty clinic in China.

    Science.gov (United States)

    Ying, Xiao-Lan; Gao, Zhen-Yan; Yan, Jin; Zhang, Meng; Wang, Ju; Xu, Jian; Markowitz, Morri; Yan, Chong-Huai

    2017-10-27

    This study explored the sources of lead exposure, identified patients' geographic distribution and evaluated the symptoms of children with elevated blood lead levels (BLLs) referred to a pediatric lead specialty clinic in China. Data were collected from 515 consecutive outpatients attending the Pediatric Lead Poisoning Clinic in Xinhua Hospital, Shanghai, China, between 2011 and 2016, referred for BLLs ≥5 μg/dL. Atomic absorption spectrometry was used to measure venous BLLs. The mean ± standard deviation age of the patients was 4.1 ± 3.2 years. Their BLLs ranged from 5 to 126 μg/dL. The geometric mean and median BLLs were 24 and 26 μg/dL, respectively. Two hundred and twenty-two children (43.1%) were exposed to industrial lead pollution-mainly from Zhejiang, Jiangsu, Hunan, Henan and Anhui provinces; whereas, 41.4% (213 cases) were induced by folk medicines used widely throughout China. Other nonindustrial sources of lead exposure included lead-containing tinfoil and tin pots. Household lead paint was a rare source. Most patients exhibited nonspecific symptoms, such as hyperactivity, attention difficulty, aggressiveness, constipation and anorexia. Industrial pollution and folk medicines are important sources of lead exposure in China. Childhood lead poisoning may be difficult to diagnose clinically as symptoms are nonspecific. Thus, blood lead screening may be necessary to identify children at high risk of exposure. Education to raise the awareness of potential sources of exposure resulting in their elimination would be expected to decrease the incidence of children with elevated BLLs.

  3. Environmental lead exposure among preschool children in Shanghai, China: blood lead levels and risk factors.

    Directory of Open Access Journals (Sweden)

    Jia Cao

    Full Text Available OBJECTIVE: To determine blood lead levels and to identify related risk factors among children in Shanghai; to explore the lead change trend of children after industrial transformation and to provide data for policy development to control environmental lead pollution in Shanghai. METHODS: A stratified-clustered-random sampling method was used. A tungsten atomizer absorption spectrophotometer was employed to determine blood lead levels. RESULTS: The arithmetic mean, geometric mean and median of blood lead levels of 0- to 6-year-old children from Shanghai were 22.49 µg/L, 19.65 µg/L and 19.5 µg/L, including 0.26% (6/2291 with concentrations ≥100 µg/L and 2.7% (61/2291 with concentrations ≥50 µg/L. Boys' levels (23.57 µg/L were greater than those of girls (21.2 µg/L. The blood lead levels increased with age. This survey showed that the Chongming district was the highest and Yangpu district was the lowest, this result is completely opposite with the earlier survey in Shanghai. Risk factors for lead contamination included housing environment, parents' education levels, social status, hobbies, and children's nutritional status. CONCLUSIONS: The blood lead levels of children in Shanghai were lower than the earlier data of Shanghai and those of published studies in China, but higher than the blood lead levels of developed countries. The blood lead levels of urban districts are higher than the central districts with the industrial transformation. Society and the government should take an active interest in childhood lead poisoning of urban areas.

  4. 40 CFR 745.65 - Lead-based paint hazards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Lead-based paint hazards. 745.65... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Hazards § 745.65 Lead-based paint hazards. (a) Paint-lead hazard. A paint-lead hazard is any of the...

  5. 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....

  6. Antimony poisoning in lead-acid batteries

    Science.gov (United States)

    Böhnstedt, W.; Radel, C.; Scholten, F.

    Linear potential sweep measurements were conducted using rotating lead-disc electrodes in sulfuric acid electrolyte containing antimony. Within the range investigated hydrogen evolution at the negative electrode is shown to be a monotonic function of the quantity of antimony deposited on the electrode surface. In the potential range -950 mV to -1150 mV versus Hg/Hg 2SO 4 the antimony deposition on lead electrodes is time dependent only; at more negative potentials the deposition rate decreases with over-voltage. At potentials antimony purging occurs. Various additives to the electrolyte were investigated to determine their ability to suppress the hydrogen evolution; aromatic aldehydes and wood flour were found to be effective. A possible mechanism is discussed.

  7. Lichens of abandoned zinc-lead mines

    Directory of Open Access Journals (Sweden)

    Urszula Bielczyk

    2013-12-01

    Full Text Available A list of lichens from areas of zinc-lead ores in Southern Poland and a review of the characteristic lichen biota of these sites is provided. In spite of the devastated and heavy metal contaminated environment, a highly diverse epigeic and epilithic lichen biota was found, including species characteristic of various anthropogenic habitats, particularly zinc and lead enriched substrates (Diploschistes muscorum, Steinia geophana, Sarcosagium campestre, Vezdaea aestivalis and V. leprosa. Also, the high-mountain species Leucocarpia biatorella, as well as very rare in Europe Thelocarpon imperceptum, and several species categorized as very rare, endangered and protected in Poland were recorded. Crustose lichens are the most abundant; among fruticose forms Cladonia spp. predominate and Stereocaulon incrustatum is common.

  8. Neurotoxic aspects of porphyinopathies: lead and succinylacetone

    Energy Technology Data Exchange (ETDEWEB)

    Silbergeld, E.K. (National Inst. of Health, Bethesda, MD); Hruska, R.E.; Bradley, D.; Lamon, J.M.; Frykholm, B.C.

    1982-12-01

    Neurotoxic effects of heavy metals and polyhalogenated hydrocarbons frequently occur at low levels of exposure, in some cases below those levels where direct toxic actions of these compounds have been demonstrated. Rats with acute and chronic lead exposure were compared to rats whose heme synthesis was inhibited by succinylacetone, as a semichronic model of the hereditary heme synthesis disorder, acute intermittent porphyria. Both treatments produce significant inhibition in activity of the enzyme delta-aminolevulinic acid dehydrase and elevations in the heme precursor delta-aminolevulinic acid (ALA) in tissues and urine. Associated with increased ALA is a significant inhibition of neurotransmission utilizing the amino acid ..gamma..-aminobutyric acid (GABA), expressed chemically and behaviorally. The results suggest that in addition to their direct molecular neurotoxicity, porphyrinopathic compounds such as lead may, through altering heme synthesis, adversely affect the brain at low levels of exposure.

  9. Spectrochemical determination of lead in wines

    Directory of Open Access Journals (Sweden)

    DRAGAN MARKOVIC

    2000-06-01

    Full Text Available The determination of lead in wines of different origin was performed by means of atomic emission spectroscopy with argon stabilized DC. U-shaped arc and electrothermal atomic absorption spectrometry. The comparison of the results obtained by the direct and standard addition method has indicated the presence of a depressive effect of the complex organic matrix. The effect is avoided successfully by mineralization, as well as by dissolution of the samples. Thus, a relative simple but precise and sensitive method involving the application of a stabilized arc and photoelectric detection with time integration of the emission signals is recommended for the determination of low concentrations of lead in wines. The complex organic matrix was investigated by recording the IR spectra of different wine fractions.

  10. Nitrogen dioxide and ozone as factors in the availability of lead from lead-based paints.

    Science.gov (United States)

    Edwards, R D; Lam, N L; Zhang, L; Johnson, M A; Kleinman, M T

    2009-11-15

    Lead-based paint remains a pervasive problem in U.S. cities, and an increasing problem in the developing world where it is still manufactured and used. Little attention has focused on the factors that increase the release of lead pigment granules from painted surfaces. Nitrogen dioxide (NO(2)) and ozone (O(3)) from transportation emissions in urban environments have the potential to react with and remove polymeric binders in paint, making pigment granules more available for subsequent transfer to hands on contact, or deposition in housedust. Here we show that exposure to NO(2) and O(3) increased the lead in wipe samples of stainless steel surfaces painted with alkyd low gloss solvent lead-based paint by 296% +/- 101 (or 0.24 microg/cm(2)) and 37% +/- 21 (or 0.025 microg/cm(2)), respectively, with corresponding changes in surface morphology indicated by reflectometry and scanning electron microscopy. Lead release from unexposed low gloss acrylic household paints was 40 times greater than comparable solvent based paints. Given that lead-based paint is still manufactured and used in many urban areas of the developing world where O(3) concentrations currently exceed historic U.S. concentrations, the interaction of air pollution with lead painted indoor surfaces may pose greater exposure risks for lead poisoning in children than previously anticipated.

  11. Remilling of salvaged wood siding coated with lead-based paint. Part 1, Lead exposure

    Science.gov (United States)

    Robert H. Falk; John J. Janowiak; Stephen D. Cosper; Susan A. Drozdz

    2005-01-01

    It is well known that the lead contained in lead-based paint (LBP) can pose a serious human health risk if ingested. In our nation’s building infrastructure, millions of meters of high quality salvageable lumber have been coated with LBP. The study presented in this and a companion paper investigated the feasibility of producing several standardized wood product...

  12. Get the Lead Out: Illinois Childhood Lead Poisoning Surveillance Report, 2001.

    Science.gov (United States)

    Illinois State Dept. of Public Health, Springfield.

    In order to highlight the importance of identifying children with elevated blood lead levels, the Illinois Department of Public Health produces its surveillance report to present state and county level data on the number of children screened for and identified with lead poisoning. In Illinois, all children between 6 and 84 months of age must be…

  13. Get the Lead Out: Illinois Childhood Lead Poisoning Surveillance Report, 1999.

    Science.gov (United States)

    Illinois State Dept. of Public Health, Springfield.

    In order to highlight the importance of identifying children with elevated blood lead levels, the Illinois Department of Public Health produces its surveillance report to present state and county level data on the number of children screened for and identified with lead poisoning. In Illinois, all children between 6 and 84 months of age must be…

  14. Get the Lead Out: Illinois Childhood Lead Poisoning Surveillance Report, 1997-1998.

    Science.gov (United States)

    Illinois State Dept. of Public Health, Springfield.

    In an effort to highlight the importance of identifying children who have been lead poisoned, the Illinois Department of Public Health produces its surveillance report to alert the community to the geographical risk of lead poisoning and to report on screening results. The hope is that increased public awareness will result in less harm to…

  15. Get the Lead Out: Illinois Childhood Lead Poisoning Surveillance Report, 2000.

    Science.gov (United States)

    Illinois State Dept. of Public Health, Springfield.

    In order to highlight the importance of identifying children with elevated blood lead levels, the Illinois Department of Public Health produces its surveillance report to present state and county level data on the number of children screened for and identified with lead poisoning. In Illinois, all children between 6 and 84 months of age must be…

  16. The influence of lead length on the fractures associated with leading corners and sidings

    CSIR Research Space (South Africa)

    Turner, PA

    1989-02-01

    Full Text Available leading and lagging panels was found generally to extend further into the lagging panel with increasing lead length. Curves fitted to the data seem to be asymptotic to a limiting fracture extent of about 15 to 20 m. More information is needed on the siding...

  17. Gluon saturation beyond (naive) leading logs

    Energy Technology Data Exchange (ETDEWEB)

    Beuf, Guillaume

    2014-12-15

    An improved version of the Balitsky–Kovchegov equation is presented, with a consistent treatment of kinematics. That improvement allows to resum the most severe of the large higher order corrections which plague the conventional versions of high-energy evolution equations, with approximate kinematics. This result represents a further step towards having high-energy QCD scattering processes under control beyond strict Leading Logarithmic accuracy and with gluon saturation effects.

  18. Environmental and biological tin and lead chemistry

    OpenAIRE

    Healy, Michael Anthony

    1980-01-01

    Tin and lead are metals of considerable commercial importance and are used in many forms in the environment. Heat and light stabilization of polyvinylchloride polymer by organotins is now a principle application of that metal. The spectroscopic properties and crystal structures are determined for some estertin precursors of these stabilizers: mono and bis-(beta-carbomethoxyethyl) tin chlorides, as well as the bis-(beta-carbomethoxyethyl) tin dichloride analogue. The feasibility of using Möss...

  19. UNC Cancer Center Director to Lead NCI.

    Science.gov (United States)

    2017-08-01

    President Donald Trump has selected Norman "Ned" Sharpless, MD, director of the University of North Carolina Lineberger Comprehensive Cancer Center, to lead the NCI. The news was met with widespread approval among cancer researchers, who view Sharpless as a strong communicator who can ably represent the needs of the cancer community in the face of proposed funding cuts. ©2017 American Association for Cancer Research.

  20. Neuroprotective effect of wormwood against lead exposure

    Directory of Open Access Journals (Sweden)

    Kharoubi O

    2011-01-01

    Full Text Available Background : Lead poisoning is a potential factor in brain damage, neurochemical dysfunction and severe behavioral problems. Considering this effect, our study was carried out to investigate the effects of wormwood to restore enzymes activities, lipid peroxidation and behavioral changes induced by lead. Methods : Thirty Wistar rats were divided into five groups (n = 6 in each group: three groups exposed to 750 ppm of lead acetate in the drinking water for 11 weeks and two groups as control. Aqueous wormwood extract (200 mg/kg body weight was administrated to intoxicated (Pb(-+A.AB and control groups (A.AB for four supplemental weeks. Activities of acetylcholinesterase (AchE, monoamine oxidase (MAO and thiobarbituric acid-reactive substances (TBARS level were determined in the hypothalamus, hippocampus, cortex and striatum of male rats and the grooming and locomotors activity were defined in all groups. Results: The intoxicated group (Pb has a significantly increased TBARS value compared with the control in all brain regions (P < 0.05 and, after treatment with the wormwood extract, a significant reduction was noted. The enzyme activity decreased significantly (P < 0.05 in the Pb group compared with the control, essentially for the hippocampus (AchE: -57%, MAO: -41% and the striatum (AchE: -43%, MAO: -51%. After wormwood extract administration, the AchE and MAO activity were significantly increased in all brain regions compared with the Pb group (P < 0.05. The behavioral test (locomotors and grooming test indicates a significant hyperactivity in the Pb group compared with the control group. After treatment with wormwood extract, the Pb(-+A.Ab indicates a lower activity compared with Pb. Conclusion : These data suggest that wormwood extract may play a very useful role in reduction of the neurotoxicological damage induced by lead.

  1. Pacemaker Lead Endocarditis Due to Trichosporon Species.

    Science.gov (United States)

    Rath, Pratap Chandra; Purohit, Bharat Vijay; Agrawal, Binod; Reddy, Krupal; Nutankavala, Lavanya; Narreddy, Suneetha; Reddy, Mallikkarjun; Abu Salim, Md

    2015-04-01

    Pacemaker-related fungal endocarditis is an uncommon and unexpected complication. It is associated with high mortality rates. Due to nonspecific clinical symptoms, negative blood culture and delays in obtaining appropriate imaging studies; late diagnosis is common with fungal endocarditis. Hereby we are reporting a rare case of pacemaker lead endocarditis due to Trichosporon species. In literature we did not find any case of pacemaker-related endocarditis due to Trichosporon species.

  2. The Prevalence of Longevity Among Leading Brands

    OpenAIRE

    Bradford T. Hudson

    2014-01-01

    The longevity of brands is embedded in scholarship involving brand processes that evolve over time such as brand equity, loyalty, nostalgia, and lifecycle. It is also an important conceptual element in the emerging topic of brand heritage. This paper offers new insight regarding the prevalence of brand longevity in a variety of industries, based on historical research about 148 leading brands ranked in prior studies by the consulting firm Interbrand. The author finds that a significant propor...

  3. Leading with integrity: a qualitative research study.

    Science.gov (United States)

    Storr, Loma

    2004-01-01

    This research paper gives an account of a study into the relationship between leadership and integrity. There is a critical analysis of the current literature for effective, successful and ethical leadership particularly, integrity. The purpose and aim of this paper is to build on the current notions of leadership within the literature, debate contemporary approaches, focussing specifically on practices within the UK National Health Service in the early 21st century. This leads to a discussion of the literature on ethical leadership theory, which includes public service values, ethical relationships and leading with integrity. A small study was undertaken consisting of 18 interviews with leaders and managers within a District General HospitaL Using the Repertory Grid technique and analysis 15 themes emerged from the constructs elicited, which were compared to the literature for leadership and integrity and other studies. As well as finding areas of overlap, a number of additional constructs were elicited which suggested that effective leadership correlates with integrity and the presence of integrity will improve organisational effectiveness. The study identified that perceptions of leadership character and behaviour are used to judge the effectiveness and integrity of a leader. However, the ethical implications and consequences of leaders' scope of power and influence such as policy and strategy are somewhat neglected and lacking in debate. The findings suggest that leaders are not judged according to the ethical nature of decision making, and leading and managing complex change but that the importance of integrity and ethical leadership correlated with higher levels of hierarchical status and that it is assumed by virtue of status and success that leaders lead with integrity. Finally, the findings of this study seem to suggest that nurse leadership capability is developing as a consequence of recent national investment.

  4. Strand misalignments lead to quasipalindrome correction

    DEFF Research Database (Denmark)

    van Noort, V.; Worning, Peder; Ussery, David

    2003-01-01

    Quasipalindromes, or imperfect inverted repeats, undergo spontaneous mutation to more-perfect inverted repeats. These mutations have been observed in many organisms, ranging from bacteria to humans, where they are associated with mutations leading to disease. We determined the relative frequency...... of quasi palindromes and perfect palindromes in more than 100 sequenced prokaryotic genomes. In nearly all cases, perfect palindromes were relatively more frequent than quasipalindromes, suggesting that quasipalindrome correction is a general mechanism for mutation in prokaryotes....

  5. Lifetime modelling of lead acid batteries

    OpenAIRE

    Bindner, H.; Cronin, T.; Lundsager, P.; Manwell, J.F.; Abdulwahid, U.; Baring-Gould, I.

    2005-01-01

    The performance and lifetime of energy storage in batteries are an important part of many renewable based energy systems. Not only do batteries impact on the system performance but they are also a significant expenditure when considering the whole lifecycle costs. Poor prediction of lifetime can, therefore, lead to uncertainty in the viability of the system in the long term. This report details the work undertaken to investigate and develop two different battery life prediction methodologies ...

  6. Chronic Heroin Dependence Leading to Adrenal Insufficiency

    Directory of Open Access Journals (Sweden)

    Gautam Das

    2014-01-01

    Full Text Available Opioids have been the mainstay for pain relief and palliation over a long period of time. They are commonly abused by drug addicts and such dependence usually imparts severe physiologic effects on multiple organ systems. The negative impact of opioids on the endocrine system is poorly understood and often underestimated. We describe a patient who developed severe suppression of the hypothalamic-pituitary adrenal (HPA axis leading to secondary adrenal insufficiency due to long standing abuse of opioids.

  7. Communication as Relational Practice of Leading

    DEFF Research Database (Denmark)

    Hansen, Lone Hersted; Larsen, Mette Vinther; Rasmussen, Jørgen Gulddahl

    2015-01-01

    This chapter highlights how communication, especially leadership communication, can be understood and practised within a relational perspective. An analysis of a specific example of communication forms the basis for a discussion of six central themes that we consider significant in a relational u...... understanding of communication and leading. The chapter ends with a discussion of how leadership communication can be understood as polyphony of voices....

  8. Leading and managing organizational change initiatives

    OpenAIRE

    Peus, Claudia; Frey, Dieter; Gerkhardt, Marit; Fischer, Peter; Traut-Mattausch, Eva

    2009-01-01

    Although indispensable for long-term economic growth, organizational changes are usually met with resistance. This article draws on psychological theories and empirical evidence to highlight why and under what conditions changes lead to resistance and what likely consequences of resistance are. Furthermore, the article discusses the variables that have been identified as success factors for organizational change initiatives. These include individual difference variables and objective characte...

  9. Dosimetric characteristics of backscattered electrons in lead

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Calatayud, Jose; Carmona, Vicente [Physics section, Radiation Oncology Department, ' La Fe' University Hospital, Avda Campanar 21, E-46009 Valencia (Spain); Ballester, Facundo [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, C/ Dr. Moliner 50, E-46100 Burjassot (Spain); IFIC-Instituto de Fisica Corpuscular, CSIC-Universitat de Valencia, C/ Dr. Moliner 50, E-46100 Burjassot (Spain). E-mail: Facundo.Ballester at uv.es; Serrano, Miguel A.; Lluch, Jose L. [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, C/ Dr. Moliner 50, E-46100 Burjassot (Spain); Casal, Emilio [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, C/ Dr. Moliner 50, E-46100 Burjassot (Spain); CND, Centro Nacional de Dosimetria, Avda. Campanar 21, E-46009 Valencia (Spain)

    2000-07-01

    In electron beam therapy, tissue overdose due to electrons backscattered from lead has been profusely studied. To quantify this dose enhancement effect, an electron backscatter factor (EBF) wasdefined as the ratio of dose at the tissue-inhomogeneity interface with and without the scatterer present. The dependence of the EBF on energy at the scatterer surface is not well known for energies lower than 3 MeV which is the most frequent clinical situation. In this work, we have done Monte Carlo calculations with the GEANT code to study EBF in lead at this energy range. The applicability of this code and the developed procedure for dose estimation has been experimentally verified. The dependence of the EBF on the beam energy incident on the scatterer has been studied for different nominal beam energies incident at the phantom's surface. The results show a trend of increase of EBF with the beam energy incident on the scatterer between 0.5 and 1.5 MeV, keeping practically constant above this energy up to 3 MeV. Backscattered electron energy spectra and depth dose curves in the 'up-stream' direction have been obtained at the various energies of the primary electron beam striking on the lead scatterer. The results of this work are compared with previously published data. (author)

  10. Does CPAP lead to change in BMI?

    Science.gov (United States)

    Redenius, Rachel; Murphy, Carli; O'Neill, Erin; Al-Hamwi, Majed; Zallek, Sarah Nath

    2008-06-15

    Obesity is an important risk factor for obstructive sleep apnea syndrome (OSAS), and weight loss can reduce apnea severity or even lead to resolution in some patients. Effective CPAP therapy may lead to weight loss by any of several proposed mechanisms, including, but not limited to, increased physical activity and increased responsiveness to leptin. This retrospective study sought to determine whether subjects who adhered to prescribed CPAP treatment for OSAS would lose weight, or gain less weight than control subjects who were either untreated or did not adhere to prescribed CPAP treatment. BMI was determined at the time of diagnosis and at followup approximately 1 year (10-14 months) later. Subjects who used CPAP > or = 4 h per night and > or = 70% of nights were considered treatment subjects. Control subjects used no treatment for OSAS or used CPAP weight gain in some; none lost weight. CPAP may affect weight in ways not measured here. Physicians should stress an active weight loss plan and not assume CPAP alone will lead to weight loss. A larger, prospective study may help clarify these findings.

  11. Do protective lead garments harbor harmful bacteria?

    Science.gov (United States)

    Grogan, Brian F; Cranston, William C; Lopez, Donna M; Furbee, Christopher; Murray, Clinton K; Hsu, Joseph R

    2011-11-09

    This study attempted to identify and characterize bacteria present on shared-use protective lead shielding garments worn in the operating room. Those worn at the authors' institution were collected and swabbed in designated 5×5-cm areas. Swabs were sent to the clinical laboratory for bacterial isolation and identification. All isolates were identified using standard microbiological methods. Isolates then underwent antimicrobial susceptibility testing as per standard hospital procedures. Of 182 total collected swabs, bacteria were isolated on only 5 (2.7%) samples. Coagulase-negative Staphylococci was identified on 3 samples and the remaining 2 grew coagulase-negative Staphylococci and gram-positive rods. The collection sites for these isolates were the lead apron, midline, bottom outer surface (n=3), thyroid shield midline, inner surface (n=1), and skirt midline, bottom inner surface (n=1). Of the collected samples, 98.3% were negative for bacterial growth. The remaining isolates were consistent with common skin flora. No multi-drug resistant organisms were identified on any garments. Standard cleaning procedures at the institution are an effective way to prevent growth of bacteria on shared-use protective lead shielding garments worn in the operating room. Copyright 2011, SLACK Incorporated.

  12. Lead tolerance in plants: strategies for phytoremediation.

    Science.gov (United States)

    Gupta, D K; Huang, H G; Corpas, F J

    2013-04-01

    Lead (Pb) is naturally occurring element whose distribution in the environment occurs because of its extensive use in paints, petrol, explosives, sludge, and industrial wastes. In plants, Pb uptake and translocation occurs, causing toxic effects resulting in decrease of biomass production. Commonly plants may prevent the toxic effect of heavy metals by induction of various celular mechanisms such as adsorption to the cell wall, compartmentation in vacuoles, enhancement of the active efflux, or induction of higher levels of metal chelates like a protein complex (metallothioneins and phytochelatins), organic (citrates), and inorganic (sulphides) complexes. Phyotochelains (PC) are synthesized from glutathione (GSH) and such synthesis is due to transpeptidation of γ-glutamyl cysteinyl dipeptides from GSH by the action of a constitutively present enzyme, PC synthase. Phytochelatin binds to Pb ions leading to sequestration of Pb ions in plants and thus serves as an important component of the detoxification mechanism in plants. At cellular level, Pb induces accumulation of reactive oxygen species (ROS), as a result of imbalanced ROS production and ROS scavenging processes by imposing oxidative stress. ROS include superoxide radical (O2(.-)), hydrogen peroxide (H2O2) and hydroxyl radical ((·)OH), which are necessary for the correct functioning of plants; however, in excess they caused damage to biomolecules, such as membrane lipids, proteins, and nucleic acids among others. To limit the detrimental impact of Pb, efficient strategies like phytoremediation are required. In this review, it will discuss recent advancement and potential application of plants for lead removal from the environment.

  13. High-Pressure Study on Lead Fluorapatite

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.; Shieh, S; Fleet, M; Akhmetov, A

    2008-01-01

    The compressional behavior of a synthetic lead fluorapatite [Pb9.35(PO4)6F2] has been investigated in situ up to about 16.7 GPa at 300 K, using a diamond-anvil cell and synchrotron X-ray diffraction. We find that the compressibility of lead fluorapatite is significantly different from that of fluorapatite [Ca10(PO4)6F2], chlorapatite [Ca10(PO4)6Cl2], and hydroxylapatite [Ca10(PO4)6(OH)2]: lead fluorapatite is much more compressible, and elastically isotropic in the investigated pressure range. The pressure-volume data fitted to the third-order Birch-Murnaghan equation yield an isothermal bulk modulus (KT) of 54.3(18) GPa and the pressure derivative (KT') of 8.1(6). If KT' is fixed at 4, the obtained KT is 68.4(16) GPa, which is approximately only two-thirds of the isothermal bulk modulus of the calcium apatites.

  14. Exposure to lead exacerbates dental fluorosis.

    Science.gov (United States)

    Leite, G A S; Sawan, R M M; Teófilo, J M; Porto, I M; Sousa, F B; Gerlach, R F

    2011-07-01

    Our aim was to test the hypothesis that co-exposure to lead and fluoride alter the severity of enamel fluorosis. Wistar rats were allocated in four groups: control, and 3 groups that received water containing 100 ppm of fluoride (F), 30 ppm of lead (Pb), or 100 ppm of F and 30 ppm of Pb (F+Pb) from the beginning of gestation. Enamel analysis and F and Pb determinations in enamel, dentine, and bone were performed in 81-day-old animals. Fluorosis was quantified using a new fluorosis index based on the identification of incisor enamel defects (white bands and white islets, representing hypomineralization, and cavities) weighted according to their severity and quantity. Hypomineralization was validated histopathologically by polarizing microscopy and microradiography. Scores were given by two blinded calibrated examiners (intra and interexaminer kappa values were 0.8 and 0.86, respectively). The control and the Pb groups presented normal enamel. The F+Pb group presented more severe enamel defects compared with the F group (Pdental fluorosis in rodents, suggesting that co-exposure to lead may affect the degree of fluorosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Lead (Pb) isotopic fingerprinting and its applications in lead pollution studies in China: a review.

    Science.gov (United States)

    Cheng, Hefa; Hu, Yuanan

    2010-05-01

    As the most widely scattered toxic metal in the world, the sources of lead (Pb) observed in contamination investigation are often difficult to identify. This review presents an overview of the principles, analysis, and applications of Pb isotopic fingerprinting in tracing the origins and transport pathways of Pb in the environment. It also summarizes the history and current status of lead pollution in China, and illustrates the power of Pb isotopic fingerprinting with examples of its recent applications in investigating the effectiveness of leaded gasoline phase-out on atmospheric lead pollution, and the sources of Pb found in various environmental media (plants, sediments, and aquatic organisms) in China. The limitations of Pb isotopic fingerprinting technique are discussed and a perspective on its development is also presented. Further methodological developments and more widespread instrument availability are expected to make isotopic fingerprinting one of the key tools in lead pollution investigation. Copyright 2009 Elsevier Ltd. All rights reserved.

  16. Iodide-assisted total lead measurement and determination of different lead fractions in drinking water samples.

    Science.gov (United States)

    Zhang, Yuanyuan; Ng, Ding-Quan; Lin, Yi-Pin

    2012-07-01

    Lead and its compounds are toxic and can harm human health, especially the intelligence development in children. Accurate measurement of total lead present in drinking water is crucial in determining the extent of lead contamination and human exposure due to drinking water consumption. The USEPA method for total lead measurement (no. 200.8) is often used to analyze lead levels in drinking water. However, in the presence of high concentration of the tetravalent lead corrosion product PbO(2), the USEPA method was not able to fully recover particulate lead due to incomplete dissolution of PbO(2) particles during strong acid digestion. In this study, a new procedure that integrates membrane separation, iodometric PbO(2) measurement, strong acid digestion and ICP-MS measurement was proposed and evaluated for accurate total lead measurement and quantification of different lead fractions including soluble Pb(2+), particulate Pb(II) carbonate and PbO(2) in drinking water samples. The proposed procedure was evaluated using drinking water reconstituted with spiked Pb(2+), spiked particulate Pb(II) carbonate and in situ formed or spiked PbO(2). Recovery tests showed that the proposed procedure and the USEPA method can achieve 93-112% and 86-103% recoveries respectively for samples containing low PbO(2) concentrations (0.018-0.076 mg Pb per L). For samples containing higher concentrations of PbO(2) (0.089-1.316 mg Pb per L), the USEPA method failed to meet the recovery requirement for total lead (85-115%) while the proposed method can achieve satisfactory recoveries (91-111%) and differentiate the soluble Pb(2+), particulate Pb(II) carbonate and PbO(2).

  17. Ameliorative Effects of Caffeic Acid on Lead Accumulation and Oxidative Stress in Lead-Exposed Mice

    Directory of Open Access Journals (Sweden)

    Maryam Lotfi-Ghahramanloo

    2016-05-01

    Full Text Available Background The currently approved treatment for lead toxicity is chelation therapy to reduce the burden of the toxic effects of lead, but the safety and efficacy of the various chelating agents may be questioned. Objectives This study was aimed to evaluate the effects of caffeic acid, a dietary non-flavonoid phenolic acid, on lead accumulation and lead-induced oxidative stress in mice. Materials and Methods In this experimental study, 24 mice were divided into four groups. Group 1 served as control. Mice in group 2 received water containing 1000 ppm lead acetate. Group 3 animals received caffeic acid (60 mg/kg body weight i.p. during lead treatment. Mice in group 4 only received caffeic acid. At the end of the experiment (18 days, blood samples were drawn and the levels of lead and some oxidative-stress related parameters were measured. Results Blood Pb concentration increased significantly in group 2 as compared to control group. Lead exposure caused significant increase of malondialdehyde and decrease of glutathione concentrations in erythrocyte haemolysate as compared to control group. Although caffeic acid was effective in normalization of the attenuated levels of erythrocytic glutathione, its administration had no significant effect in decreasing the augmented levels of erythrocytic malondialdehyde in group 3. Values of other measured parameters including erythrocytic activities of glutathione peroxidase and superoxide dismutase did not change significantly among experimental groups. Conclusions Present results show some beneficial effects of caffeic acid against lead poisoning and it can be thus proposed as a potential prophylactic treatment for amelioration of lead toxicity.

  18. Anemia risk in relation to lead exposure in lead-related manufacturing

    Directory of Open Access Journals (Sweden)

    Nan-Hung Hsieh

    2017-05-01

    Full Text Available Abstract Background Lead-exposed workers may suffer adverse health effects under the currently regulated blood lead (BPb levels. However, a probabilistic assessment about lead exposure-associated anemia risk is lacking. The goal of this study was to examine the association between lead exposure and anemia risk among factory workers in Taiwan. Methods We first collated BPb and indicators of hematopoietic function data via health examination records that included 533 male and 218 female lead-exposed workers between 2012 and 2014. We used benchmark dose (BMD modeling to estimate the critical effect doses for detection of abnormal indicators. A risk-based probabilistic model was used to characterize the potential hazard of lead poisoning for job-specific workers by hazard index (HI. We applied Bayesian decision analysis to determine whether BMD could be implicated as a suitable BPb standard. Results Our results indicated that HI for total lead-exposed workers was 0.78 (95% confidence interval: 0.50–1.26 with risk occurrence probability of 11.1%. The abnormal risk of anemia indicators for male and female workers could be reduced, respectively, by 67–77% and 86–95% by adopting the suggested BPb standards of 25 and 15 μg/dL. Conclusions We conclude that cumulative exposure to lead in the workplace was significantly associated with anemia risk. This study suggests that current BPb standard needs to be better understood for the application of lead-exposed population protection in different scenarios to provide a novel standard for health management. Low-level lead exposure risk is an occupational and public health problem that should be paid more attention.

  19. Anemia risk in relation to lead exposure in lead-related manufacturing.

    Science.gov (United States)

    Hsieh, Nan-Hung; Chung, Shun-Hui; Chen, Szu-Chieh; Chen, Wei-Yu; Cheng, Yi-Hsien; Lin, Yi-Jun; You, Su-Han; Liao, Chung-Min

    2017-05-05

    Lead-exposed workers may suffer adverse health effects under the currently regulated blood lead (BPb) levels. However, a probabilistic assessment about lead exposure-associated anemia risk is lacking. The goal of this study was to examine the association between lead exposure and anemia risk among factory workers in Taiwan. We first collated BPb and indicators of hematopoietic function data via health examination records that included 533 male and 218 female lead-exposed workers between 2012 and 2014. We used benchmark dose (BMD) modeling to estimate the critical effect doses for detection of abnormal indicators. A risk-based probabilistic model was used to characterize the potential hazard of lead poisoning for job-specific workers by hazard index (HI). We applied Bayesian decision analysis to determine whether BMD could be implicated as a suitable BPb standard. Our results indicated that HI for total lead-exposed workers was 0.78 (95% confidence interval: 0.50-1.26) with risk occurrence probability of 11.1%. The abnormal risk of anemia indicators for male and female workers could be reduced, respectively, by 67-77% and 86-95% by adopting the suggested BPb standards of 25 and 15 μg/dL. We conclude that cumulative exposure to lead in the workplace was significantly associated with anemia risk. This study suggests that current BPb standard needs to be better understood for the application of lead-exposed population protection in different scenarios to provide a novel standard for health management. Low-level lead exposure risk is an occupational and public health problem that should be paid more attention.

  20. Lead level in seminal plasma may affect semen quality for men without occupational exposure to lead

    Directory of Open Access Journals (Sweden)

    Wu Hsien-Ming

    2012-11-01

    Full Text Available Abstract Background Infertility affects approximately 10–15% of reproductive-age couples. Poor semen quality contributes to about 25% of infertile cases. Resulting from the direct effect on testicular function or hormonal alterations, heavy metals exposure has been related to impaired semen quality. The objective of this study was to assess the level of lead in the seminal plasma in men without occupational exposure to lead, and to determine the relationship between semen quality and lead concentration in the semen. Methods This is a prospective and nonrandomized clinical study conducted in University infertility clinic and academic research laboratory. Three hundred and forty-one male partners of infertile couples undergoing infertility evaluation and management were recruited to the study. Semen samples collected for the analyses of semen quality were also used for the measurement of lead concentrations. Semen samples were evaluated according to the WHO standards. Results All subjects were married and from infertile couples without occupational exposure to lead. There is a significant inverse correlation between the lead concentration in seminal plasma and sperm count. A higher semen lead concentration was correlated with lower sperm count, but not with semen volume, sperm motility or sperm morphology as assessed by simple linear regression. Conclusions We found that semen lead concentration was significantly higher among the patients with lower sperm count. To our knowledge, this is the first study to demonstrate that a high level of lead accumulation in semen may reduce the sperm count contributing to infertility of men without occupational exposure to lead.

  1. Ancient Greek lead findings in Ukraine

    Energy Technology Data Exchange (ETDEWEB)

    Danevich, F.A. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine)], E-mail: danevich@kinr.kiev.ua; Kim, S.K. [DMRC and School of Physics, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, H.J. [Physics Department, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, Y.D. [Sejong University, Seoul 143-747 (Korea, Republic of); Kobychev, V.V. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Kostezh, A.B. [Institute for Hydrometeorology Research, MSP 03650 Kyiv (Ukraine); Kropivyansky, B.N. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Laubenstein, M. [Laboratori Nazionali del Gran Sasso, I-67010 Assergi (AQ) (Italy); Mokina, V.M.; Nagorny, S.S.; Nikolaiko, A.S. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Nisi, S. [Laboratori Nazionali del Gran Sasso, I-67010 Assergi (Italy); Poda, D.V.; Tretyak, V.I. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Voronov, S.A. [Department of Underwater Heritage, Institute of Archaeology, 04210 Kyiv (Ukraine)

    2009-05-21

    In June-August 2006 an expedition with the aim to look for archaeological lead with low levels of {sup 210}Pb was organised by a Korean-Ukrainian collaboration on the shelf of the Black Sea, near the Crimean Peninsula. The first samples with {approx}0.2 ton of total mass were found at a depth of 28 m among the relics of an ancient Greek ship. Their age has been dated to the first century BC. The element composition of the samples was measured by means of X-ray fluorescence and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) analyses. The radiopurity of the lead was tested using low-level and ultra-low-level {gamma}-spectrometry at a surface laboratory in Kyiv, at the Solotvina Underground Laboratory (Ukraine), and deep underground at the Laboratori Nazionali del Gran Sasso (LNGS, Italy). The samples have been assessed at the LNGS also by means of {alpha}-spectroscopy. For all investigated radionuclides, only upper limits could be obtained. Limits on activities of radionuclides in the lead after melting were set at the level of <(0.2-0.3) mBq kg{sup -1} ({sup 60}Co), <(0.2-0.7) mBq kg{sup -1} ({sup 137}Cs), <(0.2-0.9) mBq kg{sup -1} ({sup 226}Ra), <(0.1-0.9) mBq kg{sup -1} ({sup 228}Th), <(5-7) mBq kg{sup -1} ({sup 40}K), <(0.3-1.4) Bq kg{sup -1} ({sup 210}Po), and <(12-13) Bq kg{sup -1} ({sup 210}Pb). Any {sup 210}Pb present in the lead after it was produced ca. 2000 years ago has decayed away. Assuming secular equilibrium in the {sup 238}U chain in the lead, the activity of {sup 210}Pb due to {sup 238}U can be restricted to <(5-17) mBq kg{sup -1} before melting, and <(0.2-0.9) mBq kg{sup -1} after melting.

  2. Impact of soil and dust lead on children's blood lead on Children's blood lead in contaminated areas of Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Berglund, M.; Lind, B.; Soerensen, S.; Vahter, M.

    2000-04-01

    The impact of lead in soil and dust on blood lead concentrations in young children and the risk of health effects were investigated in an urban and a mining areas of Sweden. Blood, soil, and indoor dust, as well as information on lead-exposure factors, were collected. The blood lead concentrations (total range = 9--77 {micro}g/l) the authors measured indicated a low risk for lead-induced health effects. Lead in soil and in dust had little effect on blood lead concentrations, given the present conditions and present concentration range--especially in the mining area. Urban children had significantly higher blood lead concentrations that children in the mining area, despite higher concentrations of lead in soil in the mining area. In the urban children, blood lead concentrations were influenced by parental smoking and lead in dust at day-care centers.

  3. Electrochemical and Mechanical Behavior of Lead-Silver and Lead-Bismuth Casting Alloys for Lead-Acid Battery Components

    Science.gov (United States)

    Osório, Wislei R.; Peixoto, Leandro C.; Garcia, Amauri

    2015-09-01

    The present study focuses on the interrelation of microstructure, mechanical properties, and corrosion resistance of Pb-Ag and Pb-Bi casting alloys, which can be used in the manufacture of lead-acid battery components, as potential alternatives to alloys currently used. A water-cooled solidification system is used, in which vertical upward directional solidification is promoted permitting a wide range of microstructures to be investigated. Correlations between microstructural arrays, tensile strengths, and corrosion resistances of Pb-1 wt pct Ag, Pb-2.5 wt pct Ag, Pb-1 wt pct Bi, and Pb-2.5 wt pct Bi alloys are envisaged. It is shown that a compromise between corrosion resistance (represented by the corrosion current density) and mechanical properties (represented by the ultimate tensile strength) can be obtained. Comparisons between specific strengths and mechanical/corrosion ratios are also made. It is also shown that, for microstructures solidified under cooling rates higher than 10 K/s, the Pb-Ag alloys exhibit higher specific strength and mechanical/corrosion ratio. In contrast, for casting processes in which the cooling rates are lower than 5 K/s, the dilute Pb-Bi alloy ( i.e., 1 wt pct Bi) is shown to have more appropriate requirements for lead-acid battery components. Comparisons between specific strengths, mechanical/corrosion ratio, and relative weight and cost with Pb-Sn and Pb-Sb alloys are also made.

  4. A Comparative Analysis of PID, Lead, Lag, Lead-Lag, and Cascaded Lead Controllers for a Drug Infusion System

    Directory of Open Access Journals (Sweden)

    Zuwwar Khan Jadoon

    2017-01-01

    Full Text Available Goal. The aim of this paper is to conduct a comprehensive comparative analysis between five different controllers for a drug infusion system in total intravenous anesthesia (TIVA administration. Methods. The proposed method models a dilution chamber with first order exponential decay characteristics to represent the pharmacokinetic decay of a drug. The dilution chamber is integrated with five different control techniques with a simulation-based comparative analysis performed between them. The design process is conducted using MATLAB SISOTOOL. Results. The findings show that each controller has its own merits and demerits. The results generated using MATLAB signify and confirm the effectiveness of PI and cascaded lead controllers, with cascaded lead controller as the best control technique to automate and control the propofol delivery. Conclusion. In this paper, different control techniques for measurement-based feedback-controlled propofol delivery is confirmed with promising results. Significance. The comparative analysis showed that this drug infusion platform, merged with the proper control technique, will perform eminently in the field of total intravenous anesthesia.

  5. The leaching of lead from lead-based paint in landfill environments.

    Science.gov (United States)

    Wadanambi, Lakmini; Dubey, Brajesh; Townsend, Timothy

    2008-08-30

    Lead leaching from lead-based paint (LBP) was examined using standardized laboratory protocols and tests with leachate from actual and simulated landfill environments. Two different LBP samples were tested; leaching solutions included leachates from three municipal solid waste (MSW) landfills and three construction and demolition (C&D) debris landfills. The toxicity characteristic leaching procedure (TCLP) and the synthetic precipitation leaching procedure (SPLP) were also performed. Lead concentrations were many times higher using the TCLP compared to the SPLP and the landfill leachates. No significant difference (alpha=0.05) was observed in leached lead concentrations from the MSW landfill and C&D debris landfill leachates. The impact of other building materials present in LBP debris on lead leaching was examined by testing mixtures of LBP (2%) and different building materials (98%; steel, wood, drywall, concrete). The type of substrate present impacted lead leaching results, with concrete demonstrating the most dramatic impact; the lowest lead concentrations were measured in the presence of concrete under both TCLP and SPLP extractions.

  6. 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).

  7. Cardiac Lead Management: the future of transvenous lead extraction approaches and technologies.

    Science.gov (United States)

    Segreti, Luca; Deharo, Jean-Claude

    2017-07-10

    The implantation rate of Cardiac implantable Elecrtonical Devices has consistently increased in the last 20 years, so as related complication rates. According, devices infections and malfunctions required the development of appropriate strategies, including lead removal. Transvenous lead extraction (TLE) is the gold standard for lead removal. The increasing rate of CIED implantations and of CIED related complications highlight the importance of transvenous lead extraction (TLE). TLE scenario is constantly evolving. Transvenous lead extraction (TLE) is a key procedure in lead management strategies. Optimizing lead related technology and improving TLE practice across the world are the cornerstone to improve safety and efficacy. We review the status of the art of TLE, focusing on potential future implications and improvements in terms of skillness and technologies. The increased number of extractions will increase the necessity of safe and effective TLE. The use of adequate tools, techniques and approaches, and an appropriate training are the cornerstone for safer procedures achievement. New technologies, techniques and an appropriate training is warranted across the world.

  8. Elution of lead from lead zirconate titanate ceramics to acid rain

    Science.gov (United States)

    Tsurumi, Takaaki; Takezawa, Shuhei; Hoshina, Takuya; Takeda, Hiroaki

    2017-10-01

    The amount of lead that eluted from lead zirconate titanate (PZT) ceramics to artificial acid rain was evaluated. Four kinds of PZT ceramics, namely, pure PZT at MPB composition, CuO-added PZT, PZT with 10 mol % substitution of Ba for Pb, and CuO-added PZT with 10 mol % substitution of Ba for Pb, were used as samples of the elution test. These PZT ceramics of 8 mm2 and 1.1-1.2 mm thickness were suspended in 300 ml of H2SO4 solution of pH 4.0. The concentration of lead eluted from PZT was in the range from 0.2 to 0.8 ppm. It was found that both liquid phase formation by the addition of CuO and the substitution of Ba for Pb were effective to reduce the amount of lead that eluted. By fitting the leaching out curve with a classical equation, a master curve assuming no sampling effect was obtained. The lead concentration evaluated from the amount of lead that eluted from a commercial PZT plate to H2SO4 solution of pH 5.3 was almost the same as the limit in city water. It is concluded that PZT is not harmful to health and the environment and the amount of lead that eluted from PZT can be controlled by modifying PZT composition.

  9. Evidence of recycling of lead battery waste into highly leaded jewelry.

    Science.gov (United States)

    Weidenhamer, Jeffrey D; Clement, Michael L

    2007-11-01

    Inexpensive highly leaded jewelry, much of it imported from China, remains widely available in the United States. The source materials for these items are unknown. Due to the low cost of much of this trinket jewelry, it seems likely that scrap materials may be used in their manufacture. Thirty-nine jewelry items previously determined to contain 90% or more lead by weight were analyzed for antimony content. The average antimony content of these thirty-nine items was 3.0%. The range of antimony content in the samples was from 0.3% to 6.2% antimony by weight, with twenty-seven of the samples in the range of 2-4% antimony by weight. By comparison, battery lead standard reference material obtained from the US National Institute of Standards and Technology contains 2.95% antimony by weight. While the evidence is circumstantial, the similarity in composition of these samples to battery lead is striking and supports the hypothesis that some battery lead is being recycled into highly leaded jewelry items. These results suggest that the recycling of this waste in China needs to be investigated, as the use of lead battery waste as a source material for children's jewelry poses a clear threat to children's health.

  10. Lead-glazed ceramics as major determinants of blood lead levels in Mexican women

    Energy Technology Data Exchange (ETDEWEB)

    Avila, M.H.; Romieu, I.; Rios, C.; Rivero, A.; Palazuelos, E.

    1991-08-01

    The aim of this study was to determine the main contributors to blood lead levels in a population of women from middle to low socioeconomic status in the southwestern part of Mexico City. Within this area, the authors selected a random sample of 200 women. Age ranged from 21 to 57 years, with a mean of 36 years. Among 99 women who agreed to participate in this study, blood lead levels ranged from 1 to 52 {mu}g/dL, with a mean of 10.6 {mu}g/dL. Five percent of the women had a blood lead level over 25 {mu}g/dL and 22% over 15 {mu}g/dL. There was no significant trend in blood levels according to age. The main determinants of blood lead levels were higher socioeconomic status and using lead-glazed ceramics (LGC) to prepare food. There was a significant increasing trend in blood lead levels with increasing frequency of consumption of food prepared in LGC. Among the dishes prepared in LGC, the main determinant was the consumption of stew. Time spent outdoors and consumption of tap water and of canned food were not important determinants of blood lead levels. The population attributable risk of high blood level (< 15 {mu}g/dL) due to the use of LGC was 58%. These findings demonstrate the major role of traditional pottery as a contributor to blood lead levels in this population and emphasize the need for interventions to produce lead-free pottery.

  11. Making and Breaking of Lead Halide Perovskites

    KAUST Repository

    Manser, Joseph S.

    2016-02-16

    A new front-runner has emerged in the field of next-generation photovoltaics. A unique class of materials, known as organic metal halide perovskites, bridges the gap between low-cost fabrication and exceptional device performance. These compounds can be processed at low temperature (typically in the range 80–150 °C) and readily self-assemble from the solution phase into high-quality semiconductor thin films. The low energetic barrier for crystal formation has mixed consequences. On one hand, it enables inexpensive processing and both optical and electronic tunability. The caveat, however, is that many as-formed lead halide perovskite thin films lack chemical and structural stability, undergoing rapid degradation in the presence of moisture or heat. To date, improvements in perovskite solar cell efficiency have resulted primarily from better control over thin film morphology, manipulation of the stoichiometry and chemistry of lead halide and alkylammonium halide precursors, and the choice of solvent treatment. Proper characterization and tuning of processing parameters can aid in rational optimization of perovskite devices. Likewise, gaining a comprehensive understanding of the degradation mechanism and identifying components of the perovskite structure that may be particularly susceptible to attack by moisture are vital to mitigate device degradation under operating conditions. This Account provides insight into the lifecycle of organic–inorganic lead halide perovskites, including (i) the nature of the precursor solution, (ii) formation of solid-state perovskite thin films and single crystals, and (iii) transformation of perovskites into hydrated phases upon exposure to moisture. In particular, spectroscopic and structural characterization techniques shed light on the thermally driven evolution of the perovskite structure. By tuning precursor stoichiometry and chemistry, and thus the lead halide charge-transfer complexes present in solution, crystallization

  12. Making and Breaking of Lead Halide Perovskites.

    Science.gov (United States)

    Manser, Joseph S; Saidaminov, Makhsud I; Christians, Jeffrey A; Bakr, Osman M; Kamat, Prashant V

    2016-02-16

    A new front-runner has emerged in the field of next-generation photovoltaics. A unique class of materials, known as organic metal halide perovskites, bridges the gap between low-cost fabrication and exceptional device performance. These compounds can be processed at low temperature (typically in the range 80-150 °C) and readily self-assemble from the solution phase into high-quality semiconductor thin films. The low energetic barrier for crystal formation has mixed consequences. On one hand, it enables inexpensive processing and both optical and electronic tunability. The caveat, however, is that many as-formed lead halide perovskite thin films lack chemical and structural stability, undergoing rapid degradation in the presence of moisture or heat. To date, improvements in perovskite solar cell efficiency have resulted primarily from better control over thin film morphology, manipulation of the stoichiometry and chemistry of lead halide and alkylammonium halide precursors, and the choice of solvent treatment. Proper characterization and tuning of processing parameters can aid in rational optimization of perovskite devices. Likewise, gaining a comprehensive understanding of the degradation mechanism and identifying components of the perovskite structure that may be particularly susceptible to attack by moisture are vital to mitigate device degradation under operating conditions. This Account provides insight into the lifecycle of organic-inorganic lead halide perovskites, including (i) the nature of the precursor solution, (ii) formation of solid-state perovskite thin films and single crystals, and (iii) transformation of perovskites into hydrated phases upon exposure to moisture. In particular, spectroscopic and structural characterization techniques shed light on the thermally driven evolution of the perovskite structure. By tuning precursor stoichiometry and chemistry, and thus the lead halide charge-transfer complexes present in solution, crystallization

  13. 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...

  14. Genetic susceptibility to lead poisoning—A case report

    OpenAIRE

    Bijoor, Anita R.; Venkatesh, T.

    2007-01-01

    Lead poisoning is well documented in persons occupationally exposed to lead. What is less known is, that even in persons working in lead based industries, the effect of lead and the appearance of signs and symptoms of lead poisoning is genetically determined. Three genes related to lead metabolism, exhibiting polymorphism have already been demonstrated-δALA-dehydratase, Vitamin D receptor gene and Hemochromatosis gene. These alleles determine the susceptibility of the individuals to lead. We ...

  15. Leading neutrons from polarized pp collisions

    Science.gov (United States)

    Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Ivan; Soffer, J.

    2008-10-01

    We calculate the cross section and single-spin azimuthal asymmetry, An(t) for inclusive neutron production in pp collisions at forward rapidities relative to the polarized proton. Absorptive corrections to the pion pole generate a relative phase between the spin-flip and non-flip amplitudes, which leads to an appreciable spin asymmetry. However, the asymmetry observed recently in the PHENIX experiment at RHIC at very small |t|˜0.01 GeV2 cannot be explained by this mechanism.

  16. Leading neutrons from polarized pp collisions

    OpenAIRE

    Kopeliovich, B.Z.; Potashnikova, I K; Schmidt, Ivan; Soffer, J

    2008-01-01

    We calculate the cross section and single-spin azimuthal asymmetry, A_n(t) for inclusive neutron production in pp collisions at forward rapidities relative to the polarized proton. Absorptive corrections to the pion pole generate a relative phase between the spin-flip and non-flip amplitudes, which leads to an appreciable spin asymmetry. However, the asymmetry observed recently in the PHENIX experiment at RHIC at very small |t|~0.01GeV^2 cannot be explained by this mechanism.

  17. Leading a Recovery-oriented Social Enterprise.

    Science.gov (United States)

    Raeburn, Toby; Hungerford, Catherine; Sayers, Jan; Escott, Phil; Lopez, Violeta; Cleary, Michelle

    2015-05-01

    Recovery-oriented mental health services promote the principles of recovery, such as hope and optimism, and are characterized by a personalized approach to developing consumer self-determination. Nurse leaders are increasingly developing such services as social enterprises, but there is limited research on the leadership of these programs. Leading a recovery-oriented mental health nurse social enterprise requires visionary leadership, collaboration with consumers and local health providers, financial viability, and commitment to recovery-focused practice. This article describes the framework of an Australian mental health nursing social enterprise, including the service attributes and leadership lessons that have been learned from developing program sustainability.

  18. Primary immunodeficiency leading to mycobacterial disease

    Directory of Open Access Journals (Sweden)

    Esther van de Vosse

    2015-01-01

    To facilitate the analysis of variations identified by researchers around the world, databases have been set up that contain all reported MSMD patients and mutations (see for instance: www.lovd.nl/IL12RB1. Thus far, just over 400 patients have been reported worldwide with MSMD and this is probably only the tip of the iceberg. Also, other genes are still expected to be found to cause MSMD; no genes have been reported so far in which mutations specifically lead to susceptibility to tuberculosis.

  19. Lead acid batteries simulation including experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Achaibou, N.; Malek, A. [Division Energie Solaire Photovoltaique, Centre de Developpement des Energies Renouvelables, B.P. 62, Route de l' Observatoire, Bouzareah, Alger (Algeria); Haddadi, M. [Laboratoire de Dispositif de Communication et de Conversion Photovoltaique Ecole Nationale Polytechnique, Rue Hassen Badi, El Harrach, Alger (Algeria)

    2008-12-01

    The storage of energy in batteries is a cause of the failure and loss of reliability in PV systems. The battery behavior has been largely described in the literature by many authors; the selected models are of Monegon and CIEMAT. This paper reviews the two general lead acid battery models and their agreement with experimental data. In order to validate these models, the behavior of different battery cycling currents has been simulated. Results obtained have been compared to real data. The CIEMAT model presents a good performance compared to Monegon's model. (author)

  20. Adsorption of lead over graphite oxide.

    Science.gov (United States)

    Olanipekun, Opeyemi; Oyefusi, Adebola; Neelgund, Gururaj M; Oki, Aderemi

    2014-01-24

    The adsorption efficiency and kinetics of removal of lead in presence of graphite oxide (GO) was determined using the Atomic Absorption Spectrophotometer (AAS). The GO was prepared by the chemical oxidation of graphite and characterized using FTIR, SEM, TGA and XRD. The adsorption efficiency of GO for the solution containing 50, 100 and 150 ppm of Pb(2+) was found to be 98%, 91% and 71% respectively. The adsorption ability of GO was found to be higher than graphite. Therefore, the oxidation of activated carbon in removal of heavy metals may be a viable option to reduce pollution in portable water. Published by Elsevier B.V.

  1. Problem Definition Study: Lead Beta-Resorcylate

    Science.gov (United States)

    1979-02-01

    Preteperphyrtn IX (PROTO 9) • Hamt tynthttaw Ft T Mama 7Pb«—e* Iron utilization Fa transferrin (»arum) Into reticulocytes Pb Fb GlObin...Genderen, H. and Vink, H.H. (1972), Br. J, Cancer , 16, 219. Van Esch, G.J. and Kroes, R. (1969), "The Induction of Renal Tumours by Feeding Basic...Lead Acetate to Mice and Hamsters," Br, J. Cancer , 23(4), 765-771. » Verberk, M.M. (1976), "Motor Nerve Conduction Velocity in Volunteers Ingest

  2. Transcription Blockage Leads to New Beginnings

    Science.gov (United States)

    Andrade-Lima, Leonardo C.; Veloso, Artur; Ljungman, Mats

    2015-01-01

    Environmental agents are constantly challenging cells by damaging DNA, leading to the blockage of transcription elongation. How do cells deal with transcription-blockage and how is transcription restarted after the blocking lesions are removed? Here we review the processes responsible for the removal of transcription-blocking lesions, as well as mechanisms of transcription restart. We also discuss recent data suggesting that blocked RNA polymerases may not resume transcription from the site of the lesion following its removal but, rather, are forced to start over from the beginning of genes. PMID:26197343

  3. Leading practice water monitoring in northern Australia

    Energy Technology Data Exchange (ETDEWEB)

    Bush, M.; Turner, K., E-mail: michelle.bush@environment.gov.au [Dept. of the Environment, Water, Heritage and the Arts, Supervising Scientist Div., Darwin, NT (Australia)

    2010-07-01

    Ranger Uranium Mine is undergoing an environmental impact statement assessment process to develop a Heap Leach facility to treat low grade ore on site. The facility is proposed to be located in the relatively unimpacted Gulungul catchment within the Ranger Project Area which itself is surrounded by, but excluded from, the World Heritage listed Kakadu National Park. The Supervising Scientist Division (SSD) acts to ensure the downstream environment is protected from mine-related impacts. To achieve this SSD will develop a leading practice monitoring program for Gulungul Creek to monitor potential impacts to this catchment from the Heap Leach facility. (author)

  4. Available: lead plate from COMPASS experiment

    CERN Document Server

    The COMPASS collaboration

    2014-01-01

    The COMPASS collaboration would like to offer the possibility to take over a large and thick lead plate, since it is not required anymore in the spectrometer.   It has the following dimensions: thickness 100 mm, width 4.4 m and height 2.0 m, with a square hole in the middle with dimensions of 40 cm x 40 cm. The measured weight including the metal frame it is housed in is 10,180 kg. The CERN stores reference is 44.13.30.100.9. Please contact Erwin Bielert (erwin.bielert@cern.ch or 160539) for further information and details.

  5. Superconducting properties of lithographic lead break junctions

    Science.gov (United States)

    Weber, David; Scheer, Elke

    2018-01-01

    We have fabricated mechanically controlled break junction samples made of lead (Pb) by means of state-of-the-art nanofabrication methods: electron beam lithography and physical vapour deposition. The electrical and magnetic properties were characterized in a {}3{He} cryostat and showed a hard superconducting gap. Temperature and magnetic field dependence of tunnel contacts were compared and quantitatively described by including either thermal broadening of the density of states or pair breaking in the framework of a Skalski model, respectively. We show point contact spectra of few-atom contacts and present tunneling spectra exhibiting a superconducting double-gap structure.

  6. LEADING EFFECTIVE MEETINGS IN A HOSPITALITY ORGANIZATION

    Directory of Open Access Journals (Sweden)

    Slobodan Ivanovic

    2010-06-01

    Full Text Available Today’s business environment demands of the individual manager to lead effective meetings. This is a skill which has to be studied and to be used and constantly optimized in order to keep the team focused on the goals that were set. Meetings keep track of a teams and the organizations goals that are being met or not being met. The specific focus of a certain meeting depends on what on what is to be achieved, whether that be setting goals or keeping evidence of what is being done, and to do this one needs the proper information tolead it correctly and efficiently.

  7. Research Update: Luminescence in lead halide perovskites

    Directory of Open Access Journals (Sweden)

    Ajay Ram Srimath Kandada

    2016-09-01

    Full Text Available Efficiency and dynamics of radiative recombination of carriers are crucial figures of merit for optoelectronic materials. Following the recent success of lead halide perovskites in efficient photovoltaic and light emitting technologies, here we review some of the noted literature on the luminescence of this emerging class of materials. After outlining the theoretical formalism that is currently used to explain the carrier recombination dynamics, we review a few significant works which use photoluminescence as a tool to understand and optimize the operation of perovskite based optoelectronic devices.

  8. Who Gets to Lead the Multinational Team?

    DEFF Research Database (Denmark)

    Paunova, Minna

    2017-01-01

    of their core self-evaluations. A study of over 230 individuals from 46 nationalities working in 36 self-managing teams generally supports the expected main and moderation effects. Individual core self-evaluations enhance an otherwise weak effect of English proficiency, but compensate for low levels of national......This article examines the emergence of informal leadership in multinational teams. Building on and extending status characteristics theory, the article proposes and tests a model that describes how global inequalities reproduce in multinational teams, and accounts for who gets to lead these teams...

  9. Zero Energy Schools: Architects Take the Lead

    Energy Technology Data Exchange (ETDEWEB)

    Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-28

    Zero energy schools are possible and practical, and architects are leading the way. Imagine a school so inviting that students want to come to school. Now imagine this school housed in a beautiful, light-filled building that produces more energy on an annual basis than it uses. Finally, imagine that the district built this school on the same budget as a conventional school, using typical materials, equipment, and tradespeople. Sound too good to be true Discovery Elementary School in Arlington, Virginia, is living proof that zero energy (ZE) schools are feasible, affordable, and sensible.

  10. Leading the implementation of ICT innovations

    DEFF Research Database (Denmark)

    Hansen, Morten Balle; Nørup, Iben

    2017-01-01

    This article analyzes the associations between leadership, implementation of information and communications technology (ICT) innovations, and performance. Reviewing theories and empirical evidence from the literature on leading change, ICT innovations and performance hypotheses are formulated...... and tested in an analysis of the implementation of an ICT innovation in a Danish multi-site hospital. In a quasi-experimental research design using panel data, survey responses from more than 2000 employees before and after the implementation were generated as well as qualitative interviews with change...

  11. Electronic and optical properties of lead iodide

    DEFF Research Database (Denmark)

    Ahuja, R.; Arwin, H.; Ferreira da Silva, A.

    2002-01-01

    The electronic properties and the optical absorption of lead iodide (PbI2) have been investigated experimentally by means of optical absorption and spectroscopic ellipsometry, and theoretically by a full-potential linear muffin-tin-orbital method. PbI2 has been recognized as a very promising...... detector material with a large technological applicability. Its band-gap energy as a function of temperature has also been measured by optical absorption. The temperature dependence has been fitted by two different relations, and a discussion of these fittings is given. ©2002 American Institute of Physics....

  12. Lead in water sources and lead and organochlorines in supplemental food items for the California condor

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — All but one water sample had lead concentrations below the detection limit (Table 1). The water sample collected from Ventucopa, located in Santa Barbara County, had...

  13. Mass Lead Intoxication from Informal Used Lead-Acid Battery Recycling in Dakar, Senegal

    National Research Council Canada - National Science Library

    Pascal Haefliger; Monique Mathieu-Nolf; Stephanie Lociciro; Cheikh Ndiaye; Malang Coly; Amadou Diouf; Absa Lam Faye; Aminata Sow; Joanna Tempowski; Jenny Pronczuk; Antonio Pedro Filipe Junior; Roberto Bertollini; Maria Neira

    2009-01-01

    Background and Objectives: Between November 2007 and March 2008, 18 children died from a rapidly progressive central nervous system disease of unexplained origin in a community involved in the recycling of used lead-acid batteries (ULAB...

  14. Nanostructured Lead Compounds in Electrode Materials of a Lead-Acid Battery

    OpenAIRE

    A.P. Kuzmenko; E.A. Grechushnikov; V.A. Kharseev; M.B. Dobromyslov; P.A. Rusanov

    2016-01-01

    The nanostructure and phase composition of the electrode material of lead-acid batteries, formed by chemical transformations with involvement of sulfuric acid solutions of various concentrations, water and carbon dioxide have been studied.

  15. Natural products as leads to anticancer drugs.

    Science.gov (United States)

    Gordaliza, M

    2007-12-01

    Throughout history, natural products have afforded a rich source of compounds that have found many applications in the fields of medicine, pharmacy and biology. Within the sphere of cancer, a number of important new commercialised drugs have been obtained from natural sources, by structural modification of natural compounds, or by the synthesis of new compounds, designed following a natural compound as model. The search for improved cytotoxic agents continues to be an important line in the discovery of modern anticancer drugs. The huge structural diversity of natural compounds and their bioactivity potential have meant that several products isolated from plants, marine flora and microorganisms can serve as "lead" compounds for improvement of their therapeutic potential by molecular modification. Additionally, semisynthesis processes of new compounds, obtained by molecular modification of the functional groups of lead compounds, are able to generate structural analogues with greater pharmacological activity and with fewer side effects. These processes, complemented with high-throughput screening protocols, combinatorial chemistry, computational chemistry and bioinformatics are able to afford compounds that are far more efficient than those currently used in clinical practice. Combinatorial biosynthesis is also applied for the modification of natural microbial products. Likewise, advances in genomics and the advent of biotechnology have improved both the discovery and production of new natural compounds.

  16. Peripheral Blood Signatures of Lead Exposure

    Science.gov (United States)

    LaBreche, Heather G.; Meadows, Sarah K.; Nevins, Joseph R.; Chute, John P.

    2011-01-01

    Background Current evidence indicates that even low-level lead (Pb) exposure can have detrimental effects, especially in children. We tested the hypothesis that Pb exposure alters gene expression patterns in peripheral blood cells and that these changes reflect dose-specific alterations in the activity of particular pathways. Methodology/Principal Finding Using Affymetrix Mouse Genome 430 2.0 arrays, we examined gene expression changes in the peripheral blood of female Balb/c mice following exposure to per os lead acetate trihydrate or plain drinking water for two weeks and after a two-week recovery period. Data sets were RMA-normalized and dose-specific signatures were generated using established methods of supervised classification and binary regression. Pathway activity was analyzed using the ScoreSignatures module from GenePattern. Conclusions/Significance The low-level Pb signature was 93% sensitive and 100% specific in classifying samples a leave-one-out crossvalidation. The high-level Pb signature demonstrated 100% sensitivity and specificity in the leave-one-out crossvalidation. These two signatures exhibited dose-specificity in their ability to predict Pb exposure and had little overlap in terms of constituent genes. The signatures also seemed to reflect current levels of Pb exposure rather than past exposure. Finally, the two doses showed differential activation of cellular pathways. Low-level Pb exposure increased activity of the interferon-gamma pathway, whereas high-level Pb exposure increased activity of the E2F1 pathway. PMID:21829687

  17. 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

  18. Precipitation in a lead calcium tin anode

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Gonzalez, Francisco A., E-mail: fco.aurelio@inbox.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico); Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia, Universidad Autonoma de Nuevo Leon (Mexico); Camurri, Carlos G., E-mail: ccamurri@udec.cl [Departamento de Ingenieria de Materiales, Universidad de Concepcion (Chile); Carrasco, Claudia A., E-mail: ccarrascoc@udec.cl [Departamento de Ingenieria de Materiales, Universidad de Concepcion (Chile); Colas, Rafael, E-mail: rafael.colas@uanl.edu.mx [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico); Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia, Universidad Autonoma de Nuevo Leon (Mexico)

    2012-02-15

    Samples from a hot rolled sheet of a tin and calcium bearing lead alloy were solution heat treated at 300 Degree-Sign C and cooled down to room temperature at different rates; these samples were left at room temperature to study natural precipitation of CaSn{sub 3} particles. The samples were aged for 45 days before analysing their microstructure, which was carried out in a scanning electron microscope using secondary and backscattered electron detectors. Selected X-ray spectra analyses were conducted to verify the nature of the precipitates. Images were taken at different magnifications in both modes of observation to locate the precipitates and record their position within the images and calculate the distance between them. Differential scanning calorimeter analyses were conducted on selected samples. It was found that the mechanical properties of the material correlate with the minimum average distance between precipitates, which is related to the average cooling rate from solution heat treatment. - Highlights: Black-Right-Pointing-Pointer The distance between precipitates in a lead alloy is recorded. Black-Right-Pointing-Pointer The relationship between the distance and the cooling rate is established. Black-Right-Pointing-Pointer It is found that the strengthening of the alloy depends on the distance between precipitates.

  19. Proatherogenic pathways leading to vascular calcification

    Energy Technology Data Exchange (ETDEWEB)

    Mazzini, Michael J. [Department of Cardiology, Boston University Medical Center, Boston, MA (United States); Schulze, P. Christian [Department of Medicine, Boston University Medical Center, Boston, MA (United States)]. E-mail: christian.schulze@bmc.org

    2006-03-15

    Cardiovascular disease is the leading cause of morbidity and mortality in the western world and atherosclerosis is the major common underlying disease. The pathogenesis of atherosclerosis involves local vascular injury, inflammation and oxidative stress as well as vascular calcification. Vascular calcification has long been regarded as a degenerative process leading to mineral deposition in the vascular wall characteristic for late stages of atherosclerosis. However, recent studies identified vascular calcification in early stages of atherosclerosis and its occurrence has been linked to clinical events in patients with cardiovascular disease. Its degree correlates with local vascular inflammation and with the overall impact and the progression of atherosclerosis. Over the last decade, diverse and highly regulated molecular signaling cascades controlling vascular calcification have been described. Local and circulating molecules such as osteopontin, osteoprogerin, leptin and matrix Gla protein were identified as critical regulators of vascular calcification. We here review the current knowledge on molecular pathways of vascular calcification and their relevance for the progression of cardiovascular disease.

  20. Ligand Interface Chemistry of Lead Chalcogenide Nanocrystals

    Science.gov (United States)

    Liu, Kun; Bealing, Clive; Hennig, Richard; Hennig Group Team

    2013-03-01

    Lead chalcogenides nanocrystals (NCs) have shown promise in photovoltaic applications. Surface chemistry is one of the most important, yet least understood aspects of NC synthesis and functionalization controlling their properties. For example, an incomplete surface passivation could create trap states that enhance undesired exciton recombination. Clever choices of ligands ensure that neighboring NCs are electronically coupled while maintaining their quantum size effects. These two barriers limiting performance of NC solar cells illustrate the importance of fundamental studies for the interaction between ligands and NC surfaces. We use density functional theory to determine the binding sites and energies of ligands commonly used in NC synthesis and functionalization. Specifically we study amine-, carboxyl-, and thiol-ligands on different PbSe and PbS surfaces. For methylamine ligands we find a similar binding energy on the (100) and (111) facet while carboxylic acid ligands strongly prefer the (111) facet leading to different effective NC shapes. This work was supported in part by Award No. KUS-C1-018-02, made by King Abdullah University of Science and Technology (KAUST) and by the Energy Materials Center at Cornell (EMC2) funded by the U.S. Department of Energy under Award Number DE-SC0001086

  1. Photoproduction with a Leading Proton at HERA

    CERN Document Server

    Adloff, C.; Andrieu, B.; Anthonis, T.; Arkadov, V.; Astvatsatourov, A.; Ayyaz, I.; Babaev, A.; Bahr, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bate, P.; Beglarian, A.; Behnke, O.; Beier, C.; Belousov, A.; Benisch, T.; Berger, Christoph; Berndt, T.; Bizot, J.C.; Boudry, V.; Braunschweig, W.; Brisson, V.; Broker, H.B.; Brown, D.P.; Bruckner, W.; Bruel, P.; Bruncko, D.; Burger, J.; Busser, F.W.; Bunyatyan, A.; Burkhardt, H.; Burrage, A.; Buschhorn, G.; Campbell, A.J.; Cao, Jun; Carli, T.; Caron, S.; Chabert, E.; Clarke, D.; Clerbaux, B.; Collard, C.; Contreras, J.G.; Coppens, Y.R.; Coughlan, J.A.; Cousinou, M.C.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; Davidsson, M.; Delcourt, B.; Delerue, N.; Demirchyan, R.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dixon, P.; Dodonov, V.; Dowell, J.D.; Droutskoi, A.; Duprel, C.; Eckerlin, Guenter; Eckstein, D.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellerbrock, M.; Elsen, E.; Erdmann, M.; Erdmann, W.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Ferron, S.; Fleischer, M.; Fleming, Y.H.; Flugge, G.; Fomenko, A.; Foresti, I.; Formanek, J.; Foster, J.M.; Franke, G.; Gabathuler, E.; Gabathuler, K.; Garvey, J.; Gassner, J.; Gayler, Joerg; Gerhards, R.; Ghazaryan, Samvel; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Goodwin, C.; Grab, C.; Grassler, H.; Greenshaw, T.; Grindhammer, Guenter; Hadig, T.; Haidt, D.; Hajduk, L.; Haynes, W.J.; Heinemann, B.; Heinzelmann, G.; Henderson, R.C.W.; Hengstmann, S.; Henschel, H.; Heremans, R.; Herrera, G.; Herynek, I.; Hildebrandt, M.; Hilgers, M.; Hiller, K.H.; Hladky, J.; Hoting, P.; Hoffmann, D.; Horisberger, R.; Hurling, S.; Ibbotson, M.; Issever, C .; Jacquet, M.; Jaffre, M.; Janauschek, L.; Jansen, D.M.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jones, M.A.S.; Jung, H.; Kastli, H.K.; Kant, D.; Kapichine, M.; Karlsson, M.; Karschnick, O.; Keil, F.; Keller, N.; Kennedy, J.; Kenyon, I.R.; Kermiche, S.; Kiesling, Christian M.; Kjellberg, P.; Klein, M.; Kleinwort, C.; Knies, G.; Koblitz, B.; Kolya, S.D.; Korbel, V.; Kostka, P.; Kotelnikov, S.K.; Koutouev, R.; Koutov, A.; Krasny, M.W.; Krehbiel, H.; Kroseberg, J.; Kruger, K.; Kupper, A.; Kuhr, T.; Kurca, T.; Lahmann, R.; Lamb, D.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Laycock, P.; Lebailly, E.; Lebedev, A.; Leissner, B.; Lemrani, R.; Lendermann, V.; Levonian, S.; Lindstroem, M.; List, B.; Lobodzinska, E.; Lobodzinski, B.; Loginov, A.; Loktionova, N.; Lubimov, V.; Luders, S.; Luke, D.; Lytkin, L.; Magnussen, N.; Mahlke-Kruger, H.; Malden, N.; Malinovski, E.; Malinovski, I.; Maracek, R.; Marage, P.; Marks, J.; Marshall, R.; Martyn, H.U.; Martyniak, J.; Maxfield, S.J.; Mehta, A.; Meier, K.; Merkel, P.; Meyer, A.B.; Meyer, H.; Meyer, J.; Meyer, P.O.; Mikocki, S.; Milstead, D.; Mkrtchyan, T.; Mohr, R.; Mohrdieck, S.; Mondragon, M.N.; Moreau, F.; Morozov, A.; Morris, J.V.; Muller, K.; Murin, P.; Nagovizin, V.; Naroska, B.; Naumann, J.; Naumann, T.; Nellen, G.; Newman, Paul R.; Nicholls, T.C.; Niebergall, F.; Niebuhr, C.; Nix, O.; Nowak, G.; Nunnemann, T.; Olsson, J.E.; Ozerov, D.; Panassik, V.; Pascaud, C.; Patel, G.D.; Perez, E.; Phillips, J.P.; Pitzl, D.; Poschl, R.; Potachnikova, I.; Povh, B.; Rabbertz, K.; Radel, G.; Rauschenberger, J.; Reimer, P.; Reisert, B.; Reyna, D.; Riess, S.; Risler, C.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Royon, C.; Rusakov, S.; Rybicki, K.; Sankey, D.P.C.; Scheins, J.; Schilling, F.P.; Schleper, P.; Schmidt, D.; Schmitt, S.; Schoeffel, L.; Schoning, A.; Schorner, T.; Schroder, V.; Schultz-Coulon, H.C.; Schwanenberger, C.; Sedlak, K.; Sefkow, F.; Chekelian, V.; Sheviakov, I.; Shtarkov, L.N.; Sievers, P.; Sirois, Y.; Sloan, T.; Smirnov, P.; Solochenko, V.; Soloviev, Y.; Spaskov, V.; Specka, Arnd E.; Spitzer, H.; Stamen, R.; Steinhart, J.; Stella, B.; Stellberger, A.; Stiewe, J.; Straumann, U.; Struczinski, W.; Swart, M.; Tasevsky, M.; Tchernyshov, V.; Tchetchelnitski, S.; Thompson, Graham; Thompson, P.D.; Tobien, N.; Traynor, D.; Truoel, Peter; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Turney, J.E.; Tzamariudaki, E.; Udluft, S.; Usik, A.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vassiliev, S.; Vazdik, Y.; Vichnevski, A.; Wacker, K.; Wallny, R.; Walter, T.; Waugh, B.; Weber, G.; Weber, M.; Wegener, D.; Werner, M.; White, G.; Wiesand, S.; Wilksen, T.; Winde, M.; Winter, G.G.; Wissing, C.; Wobisch, M.; Wollatz, H.; Wunsch, E.; Wyatt, A.C.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zomer, F.; Zsembery, J.; Zur Nedden, M.

    2001-01-01

    The total cross section for the photoproduction process with a leading proton in the final state has been measured at gamma p centre-of-mass energies W of 91, 181 and 231 GeV. The measured cross sections apply to the kinematic range with the transverse momentum of the scattered proton restricted to p_Tproton Xp'}(W,z)/dz is observed to be independent of W and z within the measurement errors and amounts to (8.05 +- 0.06 stat +- 0.89 syst) mub on average. The data are well described by a Triple Regge model in which the process is mediated by a mixture of exchanges with an effective Regge trajectory of intercept alpha_i(0)=0.33 +- 0.04 stat +- 0.04 syst. The total cross section for the interaction of the photon with this mixture (gamma alpha_i -> X) can be described by an effective trajectory of intercept alpha_k(0)=0.99 +- 0.01 stat +- 0.05 syst. The measured cross sections are compared with deep inelastic scattering leading proton data in the same region of z and p_Tproton for photon virtuality Q^2 > 2.5 GeV^...

  2. On the ridging of intact lead ice

    Science.gov (United States)

    Hopkins, Mark A.

    1994-08-01

    The sea ice pressure ridging process is modeled using a two-dimensional particle simulation technique. In this model, blocks are broken from an intact sheet of relatively thin lead ice driven against a thick, multiyear floe at a constant speed. The blocks of ice rubble accumulate to form the ridge sail and keel. The energy consumed in ridge growth, including dissipation, is explicitly calculated. A series of numerical experiments are performed to establish the dependence of the energetics on the thickness of the ice sheet and the friction between blocks. The results suggest that the total energy required to create a pressure ridge is an order of magnitude greater than the potential energy in the ridge structure. A typical sea ice cover in the polar regions contains a variety of ice thicknesses that evolve in response to both dynamic and thermodynamic forcing. The variable thickness of the ice cover is created by deformation, which simultaneously causes formation of thick ice through ridge building and thin ice through lead creation. Since the energy expended in deformation is largely determined by the ridging process, an understanding of the energetics of pressure ridging is critical in the determination of ice strength on a geophysical scale.

  3. Defect Tolerance in Methylammonium Lead Triiodide Perovskite

    Energy Technology Data Exchange (ETDEWEB)

    Steirer, K. Xerxes; Schulz, Philip; Teeter, Glenn; Stevanovic, Vladan; Yang, Mengjin; Zhu, Kai; Berry, Joseph J.

    2016-08-12

    Photovoltaic applications of perovskite semiconductor material systems have generated considerable interest in part because of predictions that primary defect energy levels reside outside the bandgap. We present experimental evidence that this enabling material property is present in the halide-lead perovskite, CH3NH3PbI3 (MAPbI3), consistent with theoretical predictions. By performing X-ray photoemission spectroscopy, we induce and track dynamic chemical and electronic transformations in the perovskite. These data show compositional changes that begin immediately with exposure to X-ray irradiation, whereas the predominant electronic structure of the thin film on compact TiO2 appears tolerant to the formation of compensating defect pairs of VI and VMA and for a large range of I/Pb ratios. Changing film composition is correlated with a shift of the valence-band maximum only as the halide-lead ratio drops below 2.5. This delay is attributed to the invariance of MAPbI3 electronic structure to distributed defects that can significantly transform the electronic density of states only when in high concentrations.

  4. The Prevalence of Longevity Among Leading Brands

    Directory of Open Access Journals (Sweden)

    Bradford T. Hudson

    2014-10-01

    Full Text Available The longevity of brands is embedded in scholarship involving brand processes that evolve over time such as brand equity, loyalty, nostalgia, and lifecycle. It is also an important conceptual element in the emerging topic of brand heritage. This paper offers new insight regarding the prevalence of brand longevity in a variety of industries, based on historical research about 148 leading brands ranked in prior studies by the consulting firm Interbrand. The author finds that a significant proportion (64 brands representing 43% of the total number are aged 100 years or more. The oldest brands are grouped in the food industry, while some of the youngest brands are grouped in the hospitality industry. The author applies the principles of scale and scope from the work of business historian Alfred Chandler to explain the timing of this industry emergence. The advanced age of many leading brands suggests the need for stewardship to preserve and protect the equity that resides in historic brands, and supports the argument that further attention should be directed toward the study of brand heritage effects.

  5. Leading sector development in Muaro Jambi District

    Directory of Open Access Journals (Sweden)

    Muhammad Safri

    2017-09-01

    Full Text Available Efforts to improve economic development and economic growth of Muaro Jambi Regency is a must. Efforts to increase economic development and economic growth can occur, if local governments are able to determine or identify priority sectors or become a base sector. Given the importance of determining and defining the right and correct strategy in the development of leading economic sectors/bases, it is necessary to conduct further study related to the development of leading sector policy in Muaro Jambi Regency. Analysis tools that are used are LQ (Location Quotient and SWOT analysis. The results of the analysis found that of there are three sectors that are the main sector or base in Muaro Jambi Regency, namely agriculture, livestock, plantation, fishery and forestry sector, mining and quarrying sector and manufacturing industry sector. Strategies that can be done in order to maintain and develop the sector and sub-sectors/recommended base there are several alternative strategies that combine internal environmental conditions and external environment Muaro Jambi Regency is S - O (power against opportunities, S - T (power against threats W - O (weakness to opportunity and W - T (weakness to threat. Keywords: Location Quotient, SWOT Analysis, Base Sector

  6. Lifetime modelling of lead acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, H.; Cronin, T.; Lundsager, P.

    2005-04-01

    The performance and lifetime of energy storage in batteries are an important part of many renewable based energy systems. Not only do batteries impact on the system performance but they are also a significant expenditure when considering the whole life cycle costs. Poor prediction of lifetime can, therefore, lead to uncertainty in the viability of the system in the long term. This report details the work undertaken to investigate and develop two different battery life prediction methodologies with specific reference to their use in hybrid renewable energy systems. Alongside this, results from battery tests designed to exercise batteries in similar modes to those that they experience in hybrid systems have also been analysed. These have yielded battery specific parameters for use in the prediction software and the first results in the validation process of the software are also given. This work has been part of the European Union Benchmarking research project (ENK6-CT-2001-80576), funded by the European Union, the United States and Australian governments together with other European states and other public and private financing bodies. The project has concentrated on lead acid batteries as this technology is the most commonly used. Through this work the project partner institutions have intended to provide useful tools to improve the design capabilities of organizations, private and public, in remote power systems. (au)

  7. Lead-elevated activity of xanthine oxidase in lead-exposed workers

    Directory of Open Access Journals (Sweden)

    Sławomir Kasperczyk

    2013-04-01

    Full Text Available Background: The aim of the present study was to explore the connection between lead toxicity and the activity of xanthine oxidase (XO. In addition, we indicated the uric acid (UA and creatinine levels and concentration of erythrocyte malondialdehyde (MDA to estimate oxidative stress intensity. Materials and Methods: The examined group consisted of 125 healthy male employees of zinc and lead works. The examined group was divided into tertiles according to blood lead levels. In the collected blood samples, concentrations of lead-exposure indices, UA, creatinine, and MDA as well as activity of XO were measured concomitantly. The control group consisted of 32 healthy male administrative workers who were exposed to lead only environmentally. Results: XO activity and MDA level were significantly elevated in all tertiles compared to the control group. Creatinine level was significantly elevated in the medium and high tertiles. However, the level of UA was significantly elevated in the high tertile, while in the low and medium tertile only a tendency toward higher values was observed. Conclusions: Occupational exposure to lead induces activity of XO. This induction may contribute to the observed simultaneously increased oxidative stress, measured as MDA level, and the increased level of UA. Med Pr 2013;64(2:175–180

  8. Increased lead concentration in brain and potentiation of lead-induced neuronal depression in rats after combined treatment with lead and disulfiram

    Energy Technology Data Exchange (ETDEWEB)

    Oskarsson, A.; Olson, L.; Palmer, M.R.; Lind, B.; Bjoerklund, H.; Hoffer, B.

    1985-12-01

    The effects of disulfiram (tetraethylthiuram disulfide) on blood and brain lead levels and on lead-induced changes in growth and cerebellar Purkinje neuron excitability were assessed in adult Sprague-Dawley rats. Disulfiram is metabolized to diethyldithiocarbamate, which forms a lipophilic complex with lead, and can thereby influence the tissue distribution of lead. Pregnant rats were exposed to 0.25% lead acetate or an equimolar amount of sodium acetate in the drinking water, and these treatments were continued for 4 weeks after birth. Half of the mothers from each group were given 0.1 mmole/kg disulfiram orally twice a week until parturition, after which the treatment was continued for 4 weeks in the respective pups in the form of subcutaneous injections. Although lead exposure markedly increased blood lead levels, the increase in brain lead levels was much more modest. Disulfiram markedly increased brain lead levels while blood lead levels in this group were only slightly elevated as compared to animals receiving lead alone. In addition, the lead + disulfiram group had depressed weight gain during maturation, and Purkinje neuron firing rates were reduced. The lead alone and disulfiram alone groups were not different from controls in these respects. These data suggest that disulfiram potentiates the adverse effects of lead on growth rates and on cerebellar Purkinje neuron function by facilitating the accumulation of lead in brain tissue.

  9. 24 CFR 200.800 - Lead-based paint.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Lead-based paint. 200.800 Section... DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Lead-Based Paint Poisoning Prevention § 200.800 Lead-based paint. The Lead-Based Paint Poisoning Prevention Act (42 U.S.C. 4821-4846), the Residential Lead-Based...

  10. 40 CFR 52.58 - Control strategy: Lead.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Lead. 52.58 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Alabama § 52.58 Control strategy: Lead. The lead plan... the lead standard throughout Alabama. The lead plan submitted by the State on October 7, 1985, and...

  11. Reducing Lead in Drinking Water: A Manual for Minnesota's Schools.

    Science.gov (United States)

    Minnesota State Dept. of Health, St. Paul.

    This manual was designed to assist Minnesota's schools in minimizing the consumption of lead in drinking water by students and staff. It offers step-by-step instructions for testing and reducing lead in drinking water. The manual answers: Why is lead a health concern? How are children exposed to lead? Why is lead a special concern for schools? How…

  12. Lead, mercury, and cadmium in breast milk

    Directory of Open Access Journals (Sweden)

    Kadriye Yurdakök

    2015-10-01

    Full Text Available Toxic heavy metals are the major source of environmental pollution in this new millennium. Lead, mercury, and cadmium are the most common toxic heavy metals in the environment. There is no known function of these toxic heavy metals in the human body. In females, toxic heavy metals can be accumulated in maternal body before pregnancy and may be transferred to fetus through placenta and later, via breast milk. Lead previously accumulated in maternal bones can be mobilized along with calcium in order to meet increased calcium needs of the fetus in pregnant women and for the calcium needs in human milk during lactation. Human fetus and infants are susceptible to heavy metal toxicity passing through placenta and breastmilk due to rapid growth and development of organs and tissues, especially central nervous system. However most of the damage is already done by the time the infant is born. Intrauterine lead exposure can cause growth retardation, cognitive dysfunction, low IQ scores on ability tests, and low performance in school. Biological samples, such as umbilical cord blood and breast milk, and less commonly infant hair, are used for biomonitoring of intra-uterine exposure to these toxic chemicals. Although toxic metals and other pollutants may be excreted into breast milk, their effects are unknown and this topic is subject of a growing body of research. Despite the possibility of harm from environmental contaminants in breast milk, breastfeeding is still recommended as the best infant feeding method. In fact, the species-specific components present in breast milk protect infants against infections; promote immune and neurologic system development; and may decrease the risk of disease, including allergies, obesity, insulin-dependent diabetes mellitus, inflammatory bowel disease, and sudden infant death syndrome. Breastfeeding also facilitates maternal-infant attachment. The potential risk of environmental contaminants that can be transferred from

  13. Asymptotic freedom beyond the leading order

    CERN Document Server

    Buras, Andrzej J; Ross, D A; Sachrajda, Christopher T C

    1977-01-01

    The authors make a quantitative analysis of the full G/sup 2/ interaction corrections to the leading Q/sup 2/ dependence of nu W/sub 2/ at x>or=0.4, as given by an asymptotically free gauge theory. It turns out that due to partial cancellations between various contributions the g/sup 2/ corrections are small. The best fit with the SLAC ep data after including the g/sup 2/ corrections is almost identical to that without these corrections, the only effect being a change in Lambda , the one free parameter, which sets the scale of the theory. On the other hand the effect of including target mass corrections is to improve the agreement of the prediction for nu W/sub 2//sup ep/ with data for large values of x. (20 refs).

  14. Leading the implementation of ICT innovations

    DEFF Research Database (Denmark)

    Hansen, Morten Balle; Nørup, Iben

    2017-01-01

    This article analyzes the associations between leadership, implementation of information and communications technology (ICT) innovations, and performance. Reviewing theories and empirical evidence from the literature on leading change, ICT innovations and performance hypotheses are formulated...... and tested in an analysis of the implementation of an ICT innovation in a Danish multi-site hospital. In a quasi-experimental research design using panel data, survey responses from more than 2000 employees before and after the implementation were generated as well as qualitative interviews with change...... agents. The findings indicate how differences in leadership during the ICT implementation process can have an important impact on performance after the ICT implementation process. The mobilization of initial support; directive leadership through information and technical assistance; participative...

  15. [Does cannabis use lead to schizophrenia?].

    Science.gov (United States)

    Heekeren, K

    2011-11-02

    There is a high comorbidity between cannabis use and schizophrenia. Several factors contribute to this comorbidity: secondary development of addiction, cannabis-related induction of psychosis and shared neurobiological alterations. Meanwhile, there is evidence that cannabis use is associated with an increased risk of schizophrenia. Prospective epidemiological studies have shown that a frequent cannabis use doubles the risk for schizophrenia. Interestingly, schizophrenic patients with comorbid cannabis use often show significantly better performances in neuropsychological tests than patients without cannabis use. This is nevertheless not due to a positive effect of cannabis, but a sign of cannabis-related psychosis induction in subjects with a higher level of function and less cognitive impairment. Whether cannabis use leads to schizophrenia is determined by the individual vulnerability.

  16. MANAGERS AND THEIR STYLE OF LEADING

    Directory of Open Access Journals (Sweden)

    Vlad FLOREA

    2013-06-01

    Full Text Available As main model for a manager, the German managers come from all walks of life, are graduates of higher technically and economically education, paying special attention to the individual qualities of leadership and to community professional competence to professionalism and to experience. In this paper we describe managers’ style of leading. A key feature of the Euroentrepeneur and Euromanager activity is achieving a sixth feature (creating outposts in major economic centers of Europe that is not addressing to traditional management techniques, but making use of specific techniques. The main conclusion reveals that the consolidation of European single market will grow the European management model rapidly, with its economic, social and cultural traits that will confer distinction from the North American and Japanese management.

  17. Ferroelastic Fingerprints in Methylammonium Lead Iodide Perovskite

    KAUST Repository

    Hermes, Ilka M.

    2016-02-12

    Methylammonium lead iodide (MAPbI3) perovskite materials show an outstanding performance in photovoltaic devices. However, certain material properties, especially the possible ferroic behavior, remain unclear. We observed distinct nanoscale periodic domains in the piezoresponse of MAPbI3(Cl) grains. The structure and the orientation of these striped domains indicate ferroelasticity as their origin. By correlating vertical and lateral piezoresponse force microscopy experiments performed at different sample orientations with x-ray diffraction, the preferred domain orientation was suggested to be the a1-a2-phase. The observation of these ferroelastic fingerprints appears to strongly depend on the film texture and thus the preparation route. The formation of the ferroelastic twin domains could be induced by internal strain during the cubic-tetragonal phase transition.

  18. Does string theory lead to extended inflation?

    Science.gov (United States)

    Campbell, Bruce A.; Linde, Andrei; Olive, Keith A.

    1991-05-01

    We consider the relationship between string theory and currently proposed models of extended inflation. In doing so, we discuss the conformal actions in string theory and in Jordan-Brans-Dicke gravity. We show explicitly the equivalence of pictures in which either gauge or gravitational couplings are changing with time. We demonstrate that the existence of the dilation in string theory does not naturally lead to extended inflation as currently discussed. We also discuss the resolution of the graceful exit problem of old inflation in Einstein gravity using either power-law inflation, or exponential inflation with a changing bubble formation rate. On leave of absence from School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA.

  19. [Can nitrates lead to indirect toxicity?].

    Science.gov (United States)

    Hamon, M

    2007-09-01

    For many years, nitrates have been used, at low dosages, as an additive in salted food. New laws have been promulgated to limit their concentration in water due to increased levels found in soils, rivers and even the aquifer. Although nitrate ions themselves have not toxic properties, bacterial reduction into nitrite ions (occurring even in aqueous medium) can lead to nitrous anhydride, which in turn generates nitrosonium ions. Nitrosium ions react with secondary amine to give nitrosamines, many of which are cancer-inducing agents at very low doses. Opinions on this toxicity are clear-cut and difficult to reconcile. In fact, increased levels are due, in a large part, to the use of nitrates as fertiliéers but also to bacterial transformation of human and animal nitrogenous wastes such as urea.

  20. Surprise Leads to Noisier Perceptual Decisions

    Directory of Open Access Journals (Sweden)

    Marta I Garrido

    2011-02-01

    Full Text Available Surprising events in the environment can impair task performance. This might be due to complete distraction, leading to lapses during which performance is reduced to guessing. Alternatively, unpredictability might cause a graded withdrawal of perceptual resources from the task at hand and thereby reduce sensitivity. Here we attempt to distinguish between these two mechanisms. Listeners performed a novel auditory pitch—duration discrimination, where stimulus loudness changed occasionally and incidentally to the task. Responses were slower and less accurate in the surprising condition, where loudness changed unpredictably, than in the predictable condition, where the loudness was held constant. By explicitly modelling both lapses and changes in sensitivity, we found that unpredictable changes diminished sensitivity but did not increase the rate of lapses. These findings suggest that background environmental uncertainty can disrupt goal-directed behaviour. This graded processing strategy might be adaptive in potentially threatening contexts, and reflect a flexible system for automatic allocation of perceptual resources.

  1. Situational leadership: a model for leading telecommuters.

    Science.gov (United States)

    Farmer, Leigh Ann

    2005-11-01

    To describe a leadership model aimed at assisting health care leaders to incorporate situational leadership into their practice when leading telecommuters. Technological developments have grown in two areas, including medicine and communication, which have facilitated an enhanced information exchange in health care. These technological enhancements have allowed the health care arena to expand and improve its capabilities, including the delivery of health care and the information exchange among patients, providers and workers. Traditional leadership styles must be modified to respond to the needs of telecommuters. Situational leadership gives structured guidance to the nursing leader when managing telecommuters. Situational leadership has been used in the traditional work setting and can be used in the virtual workplace. The strategies and techniques used have to be modified for the telecommuter and must focus on increasing communication.

  2. Team Lead | Center for Cancer Research

    Science.gov (United States)

    We are seeking a highly motivated Sr. Scientist to lead the newly established Single Cell Analysis Facility (SCAF) of the Center for Cancer Research (CCR) at NCI. The SCAF will house state-of-the-art single cell sequencing technologies including 10xGenomics Chromium, BD Genomics Rhapsody, DEPPArray, and other emerging single cell technologies. The successful candidate will be responsible for managing the single cell core activities and will interact with close to 200 laboratories within the CCR to design and carry out single cell experiments for cancer research. In addition to the core activities: - Will be responsible for developing new single cell technologies and making it available for CCR community - Will train/guide staff to carry out wet lab experiment from tissue/cell preparation to NexGen sequencing - Work with dedicated bioinformaticians to perform data qc and analysis - Is expected to author publications in peer reviewed scientific journals

  3. Agrochemical lead optimization by scaffold hopping.

    Science.gov (United States)

    Lamberth, Clemens

    2018-02-01

    Scaffold hopping, the exchange of a specific portion of a potential active ingredient with another substructure with the aim of finding isofunctional molecular structures with significantly different molecular backbones, often offers the chance in lead discovery or optimization to mitigate problems related to toxicity, intellectual property, and insufficient potency or stability. Scaffold hopping tools such as isosteric ring replacement including 1,3 nitrogen shift and cyclic imine-amide isosterism, but also ring opening and ring closure approaches, functional group isosterism, reversion of functional groups, chain shortening, chain lengthening, and scaffolds delivered by natural products, have become a permanent fixture of the innovation and optimization process in crop protection research. Their appropriate use will be explained through examples of success stories in the field of agrochemistry. Analogies to, but also differences from, the main categories of scaffold hopping in medicinal drug discovery are discussed. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  4. Peripheral blood signatures of lead exposure.

    Directory of Open Access Journals (Sweden)

    Heather G LaBreche

    Full Text Available BACKGROUND: Current evidence indicates that even low-level lead (Pb exposure can have detrimental effects, especially in children. We tested the hypothesis that Pb exposure alters gene expression patterns in peripheral blood cells and that these changes reflect dose-specific alterations in the activity of particular pathways. METHODOLOGY/PRINCIPAL FINDING: Using Affymetrix Mouse Genome 430 2.0 arrays, we examined gene expression changes in the peripheral blood of female Balb/c mice following exposure to per os lead acetate trihydrate or plain drinking water for two weeks and after a two-week recovery period. Data sets were RMA-normalized and dose-specific signatures were generated using established methods of supervised classification and binary regression. Pathway activity was analyzed using the ScoreSignatures module from GenePattern. CONCLUSIONS/SIGNIFICANCE: The low-level Pb signature was 93% sensitive and 100% specific in classifying samples a leave-one-out crossvalidation. The high-level Pb signature demonstrated 100% sensitivity and specificity in the leave-one-out crossvalidation. These two signatures exhibited dose-specificity in their ability to predict Pb exposure and had little overlap in terms of constituent genes. The signatures also seemed to reflect current levels of Pb exposure rather than past exposure. Finally, the two doses showed differential activation of cellular pathways. Low-level Pb exposure increased activity of the interferon-gamma pathway, whereas high-level Pb exposure increased activity of the E2F1 pathway.

  5. Lead poisoning in six captive avian species

    Science.gov (United States)

    Beyer, W. Nelson; Spann, James W.; Sileo, Louis; Franson, J. Christian

    1988-01-01

    Red-winged blackbirds (Agelaius phoeniceus), brown-headed cowbirds (Molothrus ater), common grackles (Quiscalus quiscula), mallards (Anas platyrhynchos), northern bobwhites (Colinus virginianus), and eastern screech-owls (Otus asio) were poisoned with a concentration of lead (Pb) acetate in the diet which was increased by 60% each week until half of the birds in each treatment group died; surviving birds and all control birds except screech-owis were then killed by euthanasia. An additional group of mallards was poisoned with Pb shot. The gizzards of mallards poisoned either way usually were stained with bile; some of these birds also had proventricular impaction. Most poisoned birds of the other species were emaciated but lacked other gross lesions caused by Pb poisoning. In birds other than mallards, Pb poisoning could not be diagnosed without histological or hematological examinations or analysis of tissues. Poisoned birds of all six species could be reliably separated from control birds by an increase in the protoporphyrin concentrations in the blood and by a decrease in the activity of delta-aminolevulinic acid dehydratase (ALAD) in red blood cells. Hepatic iron (Fe) concentrations varied so much among individual birds that even though median hepatic Fe concentrations increased in poisoned birds, hepatic Fe concentrations were not useful in identifying poisoned birds. Renal intranuclear inclusion bodies occurred in 83% of all birds dying from Pb poisoning. Nephrosis, myocardial necrosis, and arterial fibrinoid necrosis were occasionally present. Median hepatic Pb concentrations varied from 20 ppm (wet wt) in male red-winged blackbirds to 111 ppm in female northern bobwhites. Median renal Pb concentrations varied from 22 ppm in redwinged blackbirds to 190 ppm in female northern bobwhites. Hepatic and renal Pb concentrations varied substantially among birds within each species. Median hepatic and renal Pb concentrations of birds that died were not statistically

  6. Lead in Drinking Water in Schools and Childcare Facilities

    Science.gov (United States)

    ... States and Public Water Systems Contact Us Share Lead in Drinking Water in Schools and Childcare Facilities ... about lead in drinking water . 3Ts for Reducing Lead in Drinking Water 3Ts Toolkit View the 3Ts ...

  7. Recent Advances in the Clinical Management of Lead Poisoning

    National Research Council Canada - National Science Library

    Kianoush, Sina; Sadeghi, Mahmood; Balali-Mood, Mahdi

    2015-01-01

    .... This review deals mainly with recent developments in the management of lead poisoning. Sources of lead exposure are introduced, and methods for the primary prevention of lead poisoning are discussed...

  8. The Australian Work Exposures Study: Occupational Exposure to Lead and Lead Compounds.

    Science.gov (United States)

    Driscoll, Timothy R; Carey, Renee N; Peters, Susan; Glass, Deborah C; Benke, Geza; Reid, Alison; Fritschi, Lin

    2016-01-01

    The aims of this study were to produce a population-based estimate of the prevalence of work-related exposure to lead and its compounds, to identify the main circumstances of exposures, and to collect information on the use of workplace control measures designed to decrease those exposures. Data came from the Australian Workplace Exposures Study, a nationwide telephone survey which investigated the current prevalence and circumstances of work-related exposure to 38 known or suspected carcinogens, including lead, among Australian workers aged 18-65 years. Using the web-based tool, OccIDEAS, semi-quantitative information was collected about exposures in the current job held by the respondent. Questions were addressed primarily at tasks undertaken rather than about self-reported exposures. A total of 307 (6.1%) of the 4993 included respondents were identified as probably being exposed to lead in the course of their work. Of these, almost all (96%) were male; about half worked in trades and technician-related occupations, and about half worked in the construction industry. The main tasks associated with probable exposures were, in decreasing order: soldering; sanding and burning off paint while painting old houses, ships, or bridges; plumbing work; cleaning up or sifting through the remains of a fire; radiator-repair work; machining metals or alloys containing lead; mining; welding leaded steel; and working at or using indoor firing ranges. Where information on control measures was available, inconsistent use was reported. Applied to the Australian working population, approximately 6.3% [95% confidence interval (CI) = 5.6-7.0] of all workers (i.e. 631000, 95% CI 566000-704000 workers) were estimated to have probable occupational exposure to lead. Lead remains an important exposure in many different occupational circumstances in Australia and probably other developed countries. This information can be used to support decisions on priorities for intervention and control

  9. Effects of lead on the kidney: Roles of high-affinity lead-binding proteins

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, B.A. (Univ. of Maryland, Baltimore (United States)); DuVal, G. (Univ of Maryland Medical School, Baltimore (United States))

    1991-02-01

    Lead-induced nephropathy produces both tubular and interstitial manifestations of cell injury, but the pathophysiology of these lesions is not completely understood. Delineation of the molecular factors underlying renal handling of lead is one of central importance in understanding the mechanisms of renal cell injury from this agent. Recent studies from this laboratory have identified several distinct high-affinity lead-binding proteins (PbBP) from rat kidney and brain that appear to play critical roles in the intracellular bioavailability of lead to several essential cellular processes in these target tissues at low dose levels. These studies have also shown that the real PbBP is selectively localized in only certain nephrons and only specific segments of the renal proximal tubule. The striking nephron and cell-type specificity of the localization reaction could result from physoiological differences in nephron functional activity or selective molecular uptake mechanisms/metabolism differences that act to define target cell populations in the kidney. In addition, other preliminary studies have shown that short-term, high-dose lead exposure produces increased excretion of this protein into the urine with concomitant decreases in renal concentrations.

  10. From drug target to leads--sketching a physicochemical pathway for lead molecule design in silico.

    Science.gov (United States)

    Shaikh, S A; Jain, T; Sandhu, G; Latha, N; Jayaram, B

    2007-01-01

    The discovery of new pharmaceuticals via computer modeling is one of the key challenges in modern medicine. The advent of global networks of genomic, proteomic and metabolomic endeavors is ushering in an increasing number of novel and clinically important targets for screening. Computational methods are anticipated to play a pivotal role in exploiting the structural and functional information to understand specific molecular recognition events of the target macromolecule with candidate hits leading ultimately to the design of improved leads for the target. In this review, we sketch a system independent, comprehensive physicochemical pathway for lead molecule design focusing on the emerging in silico trends and techniques. We survey strategies for the generation of candidate molecules, docking them with the target and ranking them based on binding affinities. We present a molecular level treatment for distinguishing affinity from specificity of a ligand for a given target. We also discuss the significant aspects of drug absorption, distribution, metabolism, excretion and toxicity (ADMET) and highlight improved protocols required for higher quality and throughput of in silico methods employed at early stages of discovery. We present a realization of the various stages in the pathway proposed with select examples from the literature and from our own research to demonstrate the way in which an iterative process of computer design and validation can aid in developing potent leads. The review thus summarizes recent advances and presents a viewpoint on improvements envisioned in the years to come for automated computer aided lead molecule discovery.

  11. Lasing in robust cesium lead halide perovskite nanowires

    National Research Council Canada - National Science Library

    Samuel W. Eaton; Minliang Lai; Natalie A. Gibson; Andrew B. Wong; Letian Dou; Jie Ma; Lin-Wang Wang; Stephen R. Leone; Peidong Yang

    2016-01-01

    .... Whereas organic-inorganic lead halide perovskite materials are known for their instability, cesium lead halides offer a robust alternative without sacrificing emission tunability or ease of synthesis...

  12. Removal of lead from crude antimony by using NaPo3 as lead elimination reagent

    Directory of Open Access Journals (Sweden)

    Ye L.G.

    2015-01-01

    Full Text Available In order to solve the shortcomings when removing lead from crude antimony in the traditional antimony smelting, a new process was provided using NaPO3 as lead elimination reagent to yield phosphate slag, and it was removed by floating on the surface of the liquid antimony. Reaction mechanism was clarified by using the TG-DTA and XRD techniques and single factor experiments of removal lead from crude antimony were engaged. The results show that PbO and NaPO3 begin endothermic reaction at 863K (590°C, and the reaction mainly form NaPb4(PO43 and NaPbPO4 below 1123K (850°C and above 1123K (850°C, respectively. Sb2O3 and NaPO3 start the reaction at 773K (500°C and generate an antimonic salt compound. The reaction product of the mixture of PbO, Sb2O3 and NaPO3 show that NaPO3 reacted with PbO prior when NaPO3 was insufficient, amorphous antimony glass will be generated only when NaPO3 was adequate. Single factor experiments were taken with NaNO3 as oxidizing agent under argon, effect of reaction time, reaction temperature and dosage of NaPO3 and NaNO3 on smelting results. The average content of lead in refined antimony was 0.05340% and 98.85% of lead were removed under optimal conditions; the content of lead in antimony have meet the requirements of commercial antimony.

  13. Apical versus Non-Apical Lead: Is ICD Lead Position Important for Successful Defibrillation?

    Science.gov (United States)

    Amit, Guy; Wang, Jia; Connolly, Stuart J; Glikson, Michael; Hohnloser, Stephan; Wright, David J; Brachmann, Johannes; Defaye, Pascal; Neuzner, Joerg; Mabo, Philippe; Vanerven, Liselot; Vinolas, Xavier; O'Hara, Gilles; Kautzner, Josef; Appl, Ursula; Gadler, Fredrik; Stein, Kenneth; Konstantino, Yuval; Healey, Jeff S

    2016-05-01

    We aim to compare the acute and long-term success of defibrillation between non-apical and apical ICD lead position. The position of the ventricular lead was recorded by the implanting physician for 2,475 of 2,500 subjects in the Shockless IMPLant Evaluation (SIMPLE) trial, and subjects were grouped accordingly as non-apical or apical. The success of intra-operative defibrillation testing and of subsequent clinical shocks were compared. Propensity scoring was used to adjust for the impact of differences in baseline variables between these groups. There were 541 leads that were implanted at a non-apical position (21.9%). Patients implanted with a non-apical lead had a higher rate of secondary prevention indication. Non-apical location resulted in a lower mean R-wave amplitude (14.0 vs. 15.2, P defibrillation was similar between propensity score matched groups (89%). Over a mean follow-up of 3 years, there were no significant differences in the yearly rates of appropriate shock (5.5% vs. 5.4%, P = 0.98), failed appropriate first shock (0.9% vs. 1.0%, P = 0.66), or the composite of failed shock or arrhythmic death (2.8% vs. 2.3% P = 0.35) according to lead location. We did not detect any reduction in the ICD efficacy at the time of implant or during follow-up in patients receiving a non-apical RV lead. © 2016 Wiley Periodicals, Inc.

  14. Hazardous child labor: lead and neurocognitive development.

    Science.gov (United States)

    Ide, Lisa S R; Parker, David L

    2005-01-01

    health cannot be ignored. The study of child labor needs to take into account the baseline health of exposed individuals. In developing countries, the poorest and most vulnerable children are most often involved in work in order to earn money for survival. These children are also likely to already lack basic necessities of food and medical care, predisposing them to diarrhea, anemia, and micronutrient deficiencies. Underlying nutritional conditions may make children more susceptible to the effects of toxic substances such as lead. In addition, child laborers also may be exposed to lead and other toxic substances from their poor living conditions.

  15. Lead and Sulfur Isotope Studies of the Koru (Çanakkale, Turkey) Lead-Zinc Deposits

    OpenAIRE

    GÖKCE, GÜLCAN BOZKAYA & GÖKCE, Ahmet

    2014-01-01

    Koru (Çanakkale) barite-bearing lead-zinc deposits are typical examples of the lead-zinc deposits occurring in the Tertiary volcanic rocks which crop out in the Biga Peninsula. Volcanic rocks around the investigated deposits are distinguished as Eocene Akçaalan andesite, Oligocene Adadağı pyroclastics, Miocene Dededağ dacite and Plio-Quaternary Karaömerler basalt. The investigated deposits are hosted by Adadağı pyroclastics and show two different mineralization styles such as stockwork ore v...

  16. Lead and Sulfur Isotope Studies of the Koru (Çanakkale, Turkey) Lead-Zinc Deposits

    OpenAIRE

    GÖKCE, GÜLCAN BOZKAYA & AHMET

    2009-01-01

    Koru (Çanakkale) barite-bearing lead-zinc deposits are typical examples of the lead-zinc deposits occurring in the Tertiary volcanic rocks which crop out in the Biga Peninsula. Volcanic rocks around the investigated deposits are distinguished as Eocene Akçaalan andesite, Oligocene Adadağı pyroclastics, Miocene Dededağ dacite and Plio-Quaternary Karaömerler basalt. The investigated deposits are hosted by Adadağı pyroclastics and show two different mineralization styles such as stockwork ore v...

  17. Bone lead as a new biologic marker of lead dose: recent findings and implications for public health.

    OpenAIRE

    Hu, H.

    1998-01-01

    Measurements of lead in bone have recently become the focus of research because a) bone lead levels serve as a cumulative dosimeter of lead exposure over many years (because of lead's long residence time in bone), and cumulative exposure may be more predictive of chronic toxicity than recent exposure, which is what blood lead levels mostly reflect; b) there is suspicion that heightened bone turnover (e.g. during pregnancy, lactation, and aging) may liberate enough stored lead to pose a signif...

  18. Ecdysone receptor agonism leading to lethal molting ...

    Science.gov (United States)

    Molting is a key biological process in growth, development, reproduction and survival in arthropods. Complex neuroendocrine pathways are involved in the regulation of molting and may potentially become targets of environmental endocrine disrupting compounds (EDCs). For example, several classes of pesticides used in agriculture and aquaculture specifically target key endocrine regulators of the molting process. These chemicals may also pose hazards to non-target species by causing molting defects, thus affecting the health of the ecosystems. The present review summarized the available knowledge on molting-related endocrine regulation and disruption in arthropods (with special focus on insects and crustaceans), in order to identify research gaps and develop a toxicity mechanism-based model for environmental hazard and risk assessment. Based on the review, multiple targets in the molting processes that EDCs can interact with were characterized to inform future studies. An adverse outcome pathway (AOP) describing ecdysone receptor agonism leading to incomplete ecdysis associated mortality was developed according to the OECD guideline and evaluated for weight of evidence using the Evolved Bradford Hill Criteria. This review proposed the first invertebrate endocrine disruption AOP and may serve as a knowledge foundation for future environmental studies and AOP development. Development of high throughput toxicology (HTT) programs (e.g., ToxCast, Tox21) and potential a

  19. Lead effects on postural balance of children

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, A.; Shukla, R.; Bornschein, R.L.; Dietrich, K.N. (Univ. of Cincinnati, OH (USA)); Keith, R. (Univ. of Cincinnati Medical Center, OH (USA))

    1990-11-01

    The postural sway responses of 63 children with a mean age of 5.74 years were quantified with a Force Platform technique. The average maximum (max) blood lead (PbB) of these children during the first 5 years of life was 20.7 {mu}g/dL (range 9.2 to 32.5). The backward stepwise regression analysis for sway area response during the eyes-closed, no-foam test with all the covariates and confounders and the PbB parameters showed a significant relationship with peak or max PbB during the second year of life. These results are consistent with their previous study with a smaller group of children. The data have been analyzed to provide some insight into the role of various afferents for the maintenance of postural balance. The results suggests a hypothesis that if the max PbB had caused some level of impairment in the functional capacities or interconnectivity of the vestibular and/or proprioception systems at 2 years of age, then it is reasonable to assume that the redundancy in the postural afferent systems would naturally adapt to rely more on the remaining intact afferent system (in this case, vision).

  20. Plant mediated detoxification of mercury and lead

    Directory of Open Access Journals (Sweden)

    Brajesh Kumar

    2017-05-01

    Full Text Available In recent years, the development of efficient green chemistry methods for detoxification of metal poisoning has become a major focus of researchers. They have investigated in order to find an eco-friendly and recyclable technique for the removal of heavy metal (Pb2+, Hg2+ contamination from the natural resources. One of the most considered methods is the removal of Pb2+, Hg2+ metal using green plants and their wastes. Among these plant wastes seem to be the best candidates and they are suitable for detoxification of heavy metals. Biosorption by plants involve complex mechanisms, mainly ion exchange, chelation, adsorption by physical forces and ion entrapment in inter and intra fibrillar capillaries and spaces of the structural polysaccharide cell wall network. The advantages of using green plants and their wastes for detoxification of heavy metal have interested researchers to investigate mechanisms of metal ion uptake, and to understand the possible utilization. In this review, we discuss the role of plants and their wastes for minimizing mercury and lead pollution with their toxic effect on both human beings and plants.

  1. Designing Lead Optimisation of MMP-12 Inhibitors

    Directory of Open Access Journals (Sweden)

    Matteo Borrotti

    2014-01-01

    Full Text Available The design of new molecules with desired properties is in general a very difficult problem, involving heavy experimentation with high investment of resources and possible negative impact on the environment. The standard approach consists of iteration among formulation, synthesis, and testing cycles, which is a very long and laborious process. In this paper we address the so-called lead optimisation process by developing a new strategy to design experiments and modelling data, namely, the evolutionary model-based design for optimisation (EDO. This approach is developed on a very small set of experimental points, which change in relation to the response of the experimentation according to the principle of evolution and insights gained through statistical models. This new procedure is validated on a data set provided as test environment by Pickett et al. (2011, and the results are analysed and compared to the genetic algorithm optimisation (GAO as a benchmark. The very good performance of the EDO approach is shown in its capacity to uncover the optimum value using a very limited set of experimental points, avoiding unnecessary experimentation.

  2. Designing Lead Optimisation of MMP-12 Inhibitors

    Science.gov (United States)

    Borrotti, Matteo; De March, Davide; Slanzi, Debora; Poli, Irene

    2014-01-01

    The design of new molecules with desired properties is in general a very difficult problem, involving heavy experimentation with high investment of resources and possible negative impact on the environment. The standard approach consists of iteration among formulation, synthesis, and testing cycles, which is a very long and laborious process. In this paper we address the so-called lead optimisation process by developing a new strategy to design experiments and modelling data, namely, the evolutionary model-based design for optimisation (EDO). This approach is developed on a very small set of experimental points, which change in relation to the response of the experimentation according to the principle of evolution and insights gained through statistical models. This new procedure is validated on a data set provided as test environment by Pickett et al. (2011), and the results are analysed and compared to the genetic algorithm optimisation (GAO) as a benchmark. The very good performance of the EDO approach is shown in its capacity to uncover the optimum value using a very limited set of experimental points, avoiding unnecessary experimentation. PMID:24527058

  3. Does spectacle use lead to vestibular suppression?

    Science.gov (United States)

    Thakar, A

    2016-11-01

    Laboratory experiments indicate that changes in retinal image size result in adaptive recalibration or suppression of the vestibulo-ocular reflex. Myopia correction with spectacles or contact lenses also leads to retinal image size changes, and may bring about similar vestibulo-ocular reflex alterations. A hypothesis-generating preliminary investigation was conducted. In this cross-sectional study, findings of electronystagmography including bithermal caloric testing were compared between 17 volunteer myopes using spectacles or contact lenses and 17 volunteer emmetropes (with no refractive error). Bilateral hypoactive caloric responses were demonstrated in 6 of 11 spectacle users, in 1 of 6 contact lens users and in 1 of 17 emmetropes. Hypoactive caloric responses were significantly more likely in spectacle users than in emmetropes (p spectacles have vestibulo-ocular reflex suppression, as demonstrated by the caloric test. This has implications for the interpretation of electronystagmography and videonystagmography results, and highlights spectacle use as a possible cause of vestibular impairment. Further corroboration of these findings is warranted, with more precise and direct vestibulo-ocular reflex tests such as rotational tests and the head impulse test.

  4. Lead Oxide- PbO Humidity Sensor

    Directory of Open Access Journals (Sweden)

    Sk. Khadeer Pasha

    2010-11-01

    Full Text Available Alcohol thermal route has been used to synthesize nanocrystalline PbO at a low temperature of 75 oC using lead acetate. The synthesized PbO (P75 was annealed in the temperatures ranging from 200-500 oC for 2 h to study the effect of crystal structure and phase changes and were labeled as P200, P300, P400 and P500, respectively. X-Ray diffraction and FT-IR spectroscopy were carried out to identify the structural phases and vibrational stretching frequencies respectively. The TEM images revealed the porous nature of P75 sample which is an important criterion for the humidity sensor. The dc resistance measurements were carried out in the relative humidity (RH range 5-98 %. Among the different prepared, P75 possessed the highest humidity sensitivity of 6250, while the heat treated sample P500 have a low sensitivity of 330. The response and recovery characteristics of the maximum sensitivity sample P75 were 170 s and 40 s respectively.

  5. Electrorheology leads to healthier and tastier chocolate.

    Science.gov (United States)

    Tao, Rongjia; Tang, Hong; Tawhid-Al-Islam, Kazi; Du, Enpeng; Kim, Jeongyoo

    2016-07-05

    Chocolate is one of the most popular food types and flavors in the world. Unfortunately, at present, chocolate products contain too much fat, leading to obesity. Although this issue was called into attention decades ago, no actual solution was found. To bypass this critical outstanding problem, two manufacturers introduced some low-calorie fats to substitute for cocoa butter. Somehow, their products are not allowed in most countries. Here we show that this issue is deeply related to the basic science of soft matter, especially to the viscosity of liquid suspension and maximally random jammed (MRJ) density. When the concentration of cocoa solid is high, close to the MRJ density, removing a small amount of fat will jam the chocolate flow. Applying unconventional electrorheology to liquid chocolate with applied field in the flow direction, we aggregate the cocoa particles into prolate spheroids in micrometers. This microstructure change breaks the rotational symmetry, reduces liquid chocolate's viscosity along the flow direction, and increases its MRJ density significantly. Hence the fat level in chocolate can be effectively reduced. We are expecting a new class of healthier and tastier chocolate soon.

  6. Quantifying, Visualizing, and Monitoring Lead Optimization.

    Science.gov (United States)

    Maynard, Andrew T; Roberts, Christopher D

    2016-05-12

    Although lead optimization (LO) is by definition a process, process-centric analysis and visualization of this important phase of pharmaceutical R&D has been lacking. Here we describe a simple statistical framework to quantify and visualize the progression of LO projects so that the vital signs of LO convergence can be monitored. We refer to the resulting visualizations generated by our methodology as the "LO telemetry" of a project. These visualizations can be automated to provide objective, holistic, and instantaneous analysis and communication of LO progression. This enhances the ability of project teams to more effectively drive LO process, while enabling management to better coordinate and prioritize LO projects. We present the telemetry of five LO projects comprising different biological targets and different project outcomes, including clinical compound selection, termination due to preclinical safety/tox, and termination due to lack of tractability. We demonstrate that LO progression is accurately captured by the telemetry. We also present metrics to quantify LO efficiency and tractability.

  7. The secrets of leading companies’ success

    OpenAIRE

    Shvachka, A. V.; Швачка, А. В.

    2012-01-01

    The article is investigated the key components of success factors and strategies for leading companies worldwide. The author describes the experience of companies such as IKEA and Dell. Keywords: Elements of strategy, international companies, management, key features. В данной статье представлены ключевые компоненты и факторы успеха стратегий ведущих компаний мира. Автором описан опыт таких компаний как ИКЕА, а также Делл....

  8. Lead shot contribution to blood lead of First Nations people: The use of lead isotopes to identify the source of exposure

    Energy Technology Data Exchange (ETDEWEB)

    Tsuji, Leonard J.S. [Department of Environment and Resource Studies, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)], E-mail: ljtsuji@fes.uwaterloo.ca; Wainman, Bruce C. [Faculty of Health Sciences, McMaster University, Hamilton, Ontario, L8N 3Z5 (Canada); Martin, Ian D. [Department of Environment and Resource Studies, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Sutherland, Celine [Attawapiskat First Nation Health Services, Attawapiskat, Ontario, P0L 1A0 (Canada); Weber, Jean-Philippe; Dumas, Pierre [Centre de toxicologie, Institut national de sante publique du Quebec, Quebec City, Quebec, G1V 5B3 (Canada); Nieboer, Evert [Faculty of Health Sciences, McMaster University, Hamilton, Ontario, L8N 3Z5 (Canada); Institute of Community Medicine, University of Tromso, Tromso N-9037 (Norway)

    2008-11-01

    Although lead isotope ratios have been used to identify lead ammunition (lead shotshell pellets and bullets) as a source of exposure for First Nations people of Canada, the actual source of lead exposure needs to be further clarified. Whole blood samples for First Nations people of Ontario, Canada, were collected from participants prior to the traditional spring harvest of water birds, as well as post-harvest. Blood-lead levels and stable lead isotope ratios prior to, and after the harvest were determined by ICP-MS. Data were analyzed by paired t-tests and Wilcoxon Signed-Ranks tests. All participants consumed water birds harvested with lead shotshell during the period of study. For the group excluding six males who were potentially exposed to other sources of lead (as revealed through a questionnaire), paired t-tests and Wilcoxon Signed-Ranks tests showed consistent results: significant (p < 0.05) increases in blood-lead concentrations and blood levels of {sup 206}Pb/{sup 204}Pb and {sup 206}Pb/{sup 207}Pb towards the mean values we previously reported for lead shotshell pellets; and a significant decrease in {sup 208}Pb/{sup 206}Pb values towards the mean for lead shotshell pellets. However, when we categorized the group further into a group that did not use firearms and did not eat any other traditional foods harvested with lead ammunition other than waterfowl, our predictions for {sup 206}Pb/{sup 204}Pb, {sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 206}Pb hold true, but there was not a significant increase in blood-lead level after the hunt. It appears that the activity of hunting (i.e., use of a shotgun) was also an important route of lead exposure. The banning of lead shotshell for all game hunting would eliminate a source of environmental lead for all people who use firearms and/or eat wild game.

  9. Soil Lead and Children's Blood Lead Disparities in Pre- and Post-Hurricane Katrina New Orleans (USA).

    Science.gov (United States)

    Mielke, Howard W; Gonzales, Christopher R; Powell, Eric T

    2017-04-12

    This study appraises New Orleans soil lead and children's lead exposure before and ten years after Hurricane Katrina flooded the city. Introduction : Early childhood exposure to lead is associated with lifelong and multiple health, learning, and behavioral disorders. Lead exposure is an important factor hindering the long-term resilience and sustainability of communities. Lead exposure disproportionately affects low socioeconomic status of communities. No safe lead exposure is known and the common intervention is not effective. An essential responsibility of health practitioners is to develop an effective primary intervention. Methods : Pre- and post-Hurricane soil lead and children's blood lead data were matched by census tract communities. Soil lead and blood lead data were described, mapped, blood lead graphed as a function of soil lead, and Multi-Response Permutation Procedures statistics established disparities. Results : Simultaneous decreases occurred in soil lead accompanied by an especially large decline in children's blood lead 10 years after Hurricane Katrina. Exposure disparities still exist between children living in the interior and outer areas of the city. Conclusions : At the scale of a city, this study demonstrates that decreasing soil lead effectively reduces children's blood lead. Primary prevention of lead exposure can be accomplished by reducing soil lead in the urban environment.

  10. Uncovering the Evolution of Lead In-Use Stocks in Lead-Acid Batteries and the Impact on Future Lead Metabolism in China.

    Science.gov (United States)

    Liu, Wei; Chen, Lujun; Tian, Jinping

    2016-05-17

    This study aims to illustrate the evolution of lead in-use stocks, particularly in lead-acid batteries (LABs), and their impact on future lead metabolism in China. First, we used a bottom-up methodology to study the evolution of lead in-use stocks in China from 2000 to 2014. It was found that the lead in-use stocks increased from 0.91 to 7.75 Mt. The principal driving force of such change is the rapid development of LABs-driven electric vehicles. Then, we proposed three scenarios, low, baseline, and high in-use stocks, to project the lead demand and supply toward 2030. The results show that the LAB demand will decrease as a result of competition and replacement by lithium ion batteries. The lead demand in China will come to a peak around 2018-2020 under the three scenarios, then reduce to 3.7, 4.6, and 5.3 Mt/yr in 2030. Meanwhile, primary lead outputs will follow the increase of zinc production in China. Secondary lead recovered from spent LABs will also increase gradually. The overall unused lead stocks in 2030 will be 49.6, 44.8, and 41.2 Mt under the three scenarios, some 3.5-5.7 times as big as the lead in-use stocks. Thus, a large amount of lead will have to be safely stockpiled or exported in China.

  11. Pacemaker Lead Induced Inferior Vena Caval Thrombosis Leading to Portal Hypertension

    Directory of Open Access Journals (Sweden)

    Sharad Chandra, MD, DM

    2013-03-01

    Full Text Available Inferior vena caval thrombosis is an unusual complication of permanent pacemaker implantation. The clinical presentation due to thrombosis depends on the site of thrombus. We have described here a rare case of pacemaker lead associated thrombosis of inferior vena cava, its diagnostic work up and briefly reviewed the existing literature of this uncommon complication.

  12. Lead distribution in soils impacted by a secondary lead smelter: Experimental and modelling approaches

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Arnaud R., E-mail: arnaud.schneider@univ-reims.fr [GEGENAA, EA 3795, Université de Reims Champagne-Ardenne, SFR Condorcet FR CNRS 3417, 2 esplanade Roland Garros, 51100 Reims (France); Cancès, Benjamin; Ponthieu, Marie [GEGENAA, EA 3795, Université de Reims Champagne-Ardenne, SFR Condorcet FR CNRS 3417, 2 esplanade Roland Garros, 51100 Reims (France); Sobanska, Sophie [Laboratoire de Spectrochimie IR et Raman, UMR-CNRS 8516, Bât. C5 Université de Lille I, 59655 Villeneuve d' Ascq Cedex (France); Benedetti, Marc F. [Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot, UMR 7154, CNRS, F-75005 Paris (France); Pourret, Olivier [HydrISE, Institut Polytechnique LaSalle Beauvais, FR-60000 Beauvais (France); Conreux, Alexandra; Calandra, Ivan; Martinet, Blandine; Morvan, Xavier; Gommeaux, Maxime; Marin, Béatrice [GEGENAA, EA 3795, Université de Reims Champagne-Ardenne, SFR Condorcet FR CNRS 3417, 2 esplanade Roland Garros, 51100 Reims (France)

    2016-10-15

    Smelting activities are one of the most common sources of trace elements in the environment. The aim of this study was to determine the lead distribution in upper horizons (0–5 and 5–10 cm) of acidic soils in the vicinity of a lead-acid battery recycling plant in northern France. The combination of chemical methods (sequential extractions), physical methods (Raman microspectroscopy and scanning electron microscopy with an energy dispersive spectrometer) and multi-surface complexation modelling enabled an assessment of the behaviour of Pb. Regardless of the studied soil, none of the Pb-bearing phases commonly identified in similarly polluted environments (e.g., anglesite) were observed. Lead was mainly associated with organic matter and manganese oxides. The association of Pb with these soil constituents can be interpreted as evidence of Pb redistribution in the studied soils following smelter particle deposition. - Highlights: • Lead behavior was studied in smelter impacted soils. • A combination of experimental methods and modelling was employed. • Pb was mainly associated with organic matter and to a lesser degree with Mn oxides. • Pb was redistributed in soils after smelter particle deposition.

  13. Leading Charters: How Charter School Administrators Define Their Roles and Their Ability to Lead

    Science.gov (United States)

    Carpenter, Dick Michael, II; Peak, Charity

    2013-01-01

    Charter schools have been studied from numerous perspectives. One topic that remains under-researched, however, is charter school leadership. Therefore, we examine how charter administrators define their leadership roles and their ability to lead. Results indicate that charter principals see three primary functions in their leadership--building…

  14. Predictors and outcomes of patients requiring repeat transvenous lead extraction of pacemaker and defibrillator leads.

    Science.gov (United States)

    Claridge, Simon; Johnson, Jonathan; Sadnan, Gazi; Behar, Jonathan M; Porter, Bradley; Sieniewicz, Benjamin; Jackson, Tom; Webb, Jessica; Gould, Justin; Sohal, Manav; Hamid, Shoaib; Patel, Nik; Gill, Jaswinder; Rinaldi, Christopher A

    2018-01-05

    A proportion of patients who undergo an initial lead extraction procedure will require a second, repeat extraction. Data regarding this clinical entity are scarce and neither the predisposing risk factors for, nor outcomes from, these procedures have been described previously. We sought to determine the incidence, risk factors, and outcomes of repeat lead extraction. A database of extraction procedures from 2001 to 2015 was analyzed. Repeat extraction procedures were identified and the indication for extraction was dichotomized into infection and lead-related problems. Univariate and multivariate analyses were performed to identify predictors of repeat extraction. 807 extraction procedures were identified in 755 patients of whom 6% required a repeat extraction. At multivariate analysis, only suffering a major complication at the initial extraction procedure (odds ratio [OR] 21.5, 95% confidence interval [CI] 2.69-171.92; P extraction. When repeat extraction was required for infection there was a significant increase in mortality compared with those who did not require a second procedure (36% vs 23%; P  =  0.02). Repeat lead extraction is required in 6% of cases. Complexity of device, age at extraction, and a major complication at the first extraction were predictors of repeat extraction. Mortality is significantly increased where the repeat procedure is for infection. Clinicians should alert patients to the potential need for further extraction and the increased risks of repeat procedures when indicated for infection. © 2018 Wiley Periodicals, Inc.

  15. Activation analysis of targets and lead in a lead slowing down spectrometer system

    Directory of Open Access Journals (Sweden)

    Yongdeok Lee

    2018-02-01

    Full Text Available A neutron generation system was developed to induce fissile fission in a lead slowing down spectrometer (LSDS system. The source neutron is one of the key factors for LSDS system work. The LSDS was developed to quantify the isotopic contents of fissile materials in spent nuclear fuel and recycled fuel. The source neutron is produced at a multilayered target by the (e,γ(γ,n reaction and slowed down at the lead medium. Activation analysis of the target materials is necessary to estimate the lifetime, durability, and safety of the target system. The CINDER90 code was used for the activation analysis, and it can involve three-dimensional geometry, position dependent neutron flux, and multigroup cross-section libraries. Several sensitivity calculations for a metal target with different geometries, materials, and coolants were done to achieve a high neutron generation rate and a low activation characteristic. Based on the results of the activation analysis, tantalum was chosen as a target material due to its better activation characteristics, and helium gas was suggested as a coolant. In addition, activation in a lead medium was performed. After a distance of 55 cm from the lead surface to the neutron incidence, the neutron intensity dramatically decreased; this result indicates very low activation.

  16. Healthy Beginnings: Lead Safe Families. An English as a Second Language Curriculum on Lead Poisoning Prevention.

    Science.gov (United States)

    Education Development Center, Inc., Newton, MA.

    The materials are designed to help teachers of English as a Second Language (ESL) at all levels educate adult students about hazards and prevention of lead poisoning, and to encourage use of English within the context of daily living situations. The materials consist of: a teacher's guide that describes the instructional units and lists resources…

  17. Can You Lead Me Now? Leading in the Complex World of Homeland Security

    Science.gov (United States)

    2007-09-01

    information processing, and modifying ones own views and direction. Ronald Heifetz suggests, “Rather than define leadership either as a position...maintaining a rhythm of contact and withdrawal from 41 Ronald A. Heifetz , Leadership without Easy...perhaps Fenty needed to demonstrate his authority by removing a popular chief. Else, as Ronald Heifetz and Marty Linsky suggest, leading is a

  18. Evidence of a Lead Metathesis Product from Calcium Hydroxyapatite Dissolution in Lead Nitrate Solution

    Directory of Open Access Journals (Sweden)

    Oratai Saisa-ard

    2014-01-01

    Full Text Available Calcium hydroxyapatite, CaHAp, synthesized by the precipitation method, was utilized to study the calcium-lead metathesis reaction on dissolution in a lead nitrate solution under reflux conditions to prepare larger lead hydroxyapatite, PbHAp, crystals from CaHAp. SEM images show development of crystalline PbHAp on the surfaces of CaHAp. The needle-like crystal morphology observed for PbHAp after 24 h reaction time developed into hexagonal-rod crystal morphology within 48 h reaction time. The largest PbHAp crystals obtained from 48 h reaction time have approximate size of 10 × 10 × 40 μm. Powder X-ray diffraction results show mixed phases of CaHAp and PbHAp due to difficulty in separating the PbHAp product from the CaHAp substrate. The PbHAp peaks observed after 24 h of reaction sharpen and increase in intensity after 48 h of reaction confirming that the PbHAp phase is the major product for the 48 h reaction time. EDX results of the crystalline products show high intensity Pb peaks with lead to phosphorous ratio (5 : 3 as expected for PbHAp. Lower intensity Ca peaks are also observed, consistent with incomplete coverage of the CaHAp growth substrate.

  19. CAN FLUORIDATION AFFECT WATER LEAD (II) LEVELS AND LEAD (II) NEUROTOXICITY?

    Science.gov (United States)

    Recent reports have attempted to show that certain approaches to fluoridating potable water is linked to increased levels of lead(II) in the blood. We examine these claims in light of the established science and critically evaluate their significance. The completeness of hexafl...

  20. Improving the Performance of Formamidinium and Cesium Lead Triiodide Perovskite Solar Cells using Lead Thiocyanate Additives.

    Science.gov (United States)

    Yu, Yue; Wang, Changlei; Grice, Corey R; Shrestha, Niraj; Chen, Jing; Zhao, Dewei; Liao, Weiqiang; Cimaroli, Alexander J; Roland, Paul J; Ellingson, Randy J; Yan, Yanfa

    2016-12-08

    Formamidinium lead triiodide (FAPbI3 ) is considered as an alternative to methylammonium lead triiodide (MAPbI3 ) because of its lower band gap and better thermal stability. However, owing to the large size of FA cations, it is difficult to synthesize high-quality FAPbI3 thin films without the formation of an undesirable yellow phase. Smaller sized cations, such as MA and Cs, have been successfully used to suppress the formation of the yellow phase. Whereas FA and MA lead triiodide perovskite solar cells (PVSCs) have achieved power conversion efficiencies (PCEs) higher than 20 %, the PCEs of formamidinium and cesium lead triiodide (FA1-x Csx PbI3 ) PVSCs have been only approximately 16.5 %. Herein, we report our examination of the main factors limiting the PCEs of (FA1-x Csx PbI3 ) PVSCs. We find that one of the main limiting factors could be the small grain sizes (≈120 nm), which leads to relatively short carrier lifetimes. We further find that adding a small amount of lead thiocyanate [Pb(SCN)2 ] to the precursors can enlarge the grain size of (FA1-x Csx PbI3 ) perovskite thin films and significantly increase carrier lifetimes. As a result, we are able to fabricate (FA1-x Csx PbI3 ) PVSCs with significantly improved open-circuit voltages and fill factors and, therefore, enhanced PCEs. With an optimal 0.5 mol % Pb(SCN)2 additive, the average PCE is increased from 16.18±0.50 (13.45±0.78) % to 18.16±0.54 (16.86±0.63) % for planar FA0.8 Cs0.2 PbI3 PVSCs if measured under reverse (forward) voltage scans. The champion cell registers a PCE of 19.57 (18.12) % if measured under a reverse (forward) voltage scan, which is comparable to that of the best-performing MA-containing planar FA-based lead halide PVSCs. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Antibiotic impregnated catheter coverage of deep brain stimulation leads facilitates lead preservation after hardware infection.

    Science.gov (United States)

    Dlouhy, Brian J; Reddy, Ambur; Dahdaleh, Nader S; Greenlee, Jeremy D W

    2012-10-01

    Deep brain stimulation (DBS) has become a reliable and effective treatment for many disorders. However, the risk of long-term hardware-related complications is notable, and most concerning is hardware-related infections. Given the risk of hardware removal in the setting of infection, we retrospectively examined the implementation of a novel technique using antibiotic covered catheter protection of DBS leads after infection. The effect on hardware salvage and ease of reimplantation of the DBS extension and implantable pulse generator (IPG) was examined. A total of nine (9%) out of 100 DBS patients met the inclusion criteria with 11 DBS hardware-related infections at either the frontal, parietal, or IPG sites, from June 2003 to November 2010, at our institution. Subsequent to the initial patient in the series, a total of eight patients had placement of a short segment (approx. 4 cm long) of antibiotic impregnated catheter (Bactiseal, Codman, Johnson & Johnson, Raynham, MA, USA) over the distal end of the DBS leads at the parietal incision. Seven of these eight patients presented with pus and deep tissue infections around the hardware at either the frontal, parietal, or chest incisions. In seven of these eight patients (87.5%) we were able to protect and salvage their DBS leads without need for removal. In conclusion, this novel technique provides a simple reimplantation operation, with a decreased risk of DBS lead damage. It may improve the preservation of DBS leads when hardware infection occurs, is inexpensive, and confers no additional risks to patients. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. New mechanisms in lead biodynamics at ultra-low levels.

    Science.gov (United States)

    Patterson, C; Settle, D

    1993-01-01

    It has been found that the mean concentration of 15 micrograms Pb/g bone ash in typical Americans today is 1000 times greater than the natural level of lead in Homo sapiens sapiens determined from analyses of ancient human bones. Since body burdens of lead only 3 to 5-fold greater than typical induce overtly poisonous effects, unrecognized dysfunctions caused by lead are probably widespread among Americans. Previous toxicological studies by others to delineate ill effects were made by comparisons of biological systems to which lead was added with systems to which no lead was added. It is now seen that such studies dealt entirely with unnatural mechanisms in lead biodynamics, and provided no knowledge of the operation of unperturbed natural mechanisms, because "non-leaded" controls were actually highly traumatized by unrecognized excessive lead exposures. New work should be carried out that would use an ultra-low lead diet to grow rats possessing "natural" lead levels which could be used as controls. Metabolisms of lead in these controls should be compared with metabolisms of lead in biological systems of rats traumatized by excessive lead exposures corresponding to typical levels within people today. Such comparisons would disclose previously unknown characteristics of intra-cellular processing of lead within osseous, neuronal, hepatic, renal and muscle tissues, and in red blood cells and sera, together with sizes and residence times of lead reservoirs in those tissues during fetal growth, maturation and adult aging in rats exposed to natural lead levels.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. New mechanisms in lead biodynamics at ultra-low levels

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, C.; Settle, D. (California Institute of Technology, Pasadena (United States))

    It has been found that the mean concentration of 15 micrograms Pb/g bone ash in typical Americans today is 1000 times greater than the natural level of lead in Homo sapiens sapiens determined from analyses of ancient human bones. Since body burdens of lead only 3 to 5-fold greater than typical induce overtly poisonous effects, unrecognized dysfunctions caused by lead are probably widespread among Americans. Previous toxicological studies by others to delineate ill effects were made by comparisons of biological systems to which lead was added with systems to which no lead was added. It is now seen that such studies dealt entirely with unnatural mechanisms in lead biodynamics, and provided no knowledge of the operation of unperturbed natural mechanisms, because non-leaded controls were actually highly traumatized by unrecognized excessive lead exposures. New work should be carried out that would use an ultra-low lead diet to grow rats possessing natural lead levels which could be used as controls. Metabolisms of lead in these controls should be compared with metabolisms of lead in biological systems of rats traumatized by excessive lead exposures corresponding to typical levels within people today. Such comparisons would disclose previously unknown characteristics of intra-cellular processing of lead within osseous, neuronal, hepatic, renal and muscle tissues, and in red blood cells and sera, together with sizes and residence times of lead reservoirs in those tissues during fetal growth, maturation and adult aging in rats exposed to natural lead levels.

  4. Case report: Coccidiosis and lead poisoning in Canada geese

    Science.gov (United States)

    Locke, L.N.; Bagley, George E.

    1967-01-01

    Four dead Canada geese (Branta canadensis L.) collected at the Prime Hook National Wildlife Refuge, Delaware were found to have both marked duodenal lesions of coccidiosis and high levels of lead in the liver. Although only one goose had lead shot in the gizzard, all four had levels of lead in the liver suggestive of lead poisoning.

  5. Evaluation of lead concentration levels of children's paly ground in ...

    African Journals Online (AJOL)

    Leaded paint and lead from exhaust of vehicle have been observed to be the major contributors of lead contamination, resulting to soil contamination. African infants by way of culture have direct contact with contaminated soil. The study investigated, lead contamination of soil in children's playgrounds of some selected ...

  6. 24 CFR 891.325 - Lead-based paint requirements.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Lead-based paint requirements. 891... Section 811 Supportive Housing for Persons With Disabilities § 891.325 Lead-based paint requirements. The requirements of the Lead-Based Paint Poisoning Prevention Act (42 U.S.C. 4821-4846), the Residential Lead-Based...

  7. 24 CFR 598.408 - Lead-based paint requirements.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Lead-based paint requirements. 598... DESIGNATIONS Post-Designation Requirements § 598.408 Lead-based paint requirements. The Lead-Based Paint Poisoning Prevention Act (42 U.S.C. 4821-4846), the Residential Lead-Based Paint Hazard Reduction Act of...

  8. 40 CFR 52.1375 - Control strategy: Lead.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Lead. 52.1375 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Montana § 52.1375 Control strategy: Lead. Determination—EPA has determined that the East Helena Lead nonattainment area has attained the lead national...

  9. Environmental lead pollution and contamination in food around ...

    African Journals Online (AJOL)

    Exposure to lead (Pb) through food, water, or contaminated air has adverse health impacts that are particularly severe in children. Many countries have outlawed the use of leaded petrol, and enacted policies and regulations limiting lead pollution, and lead levels in foods. However, African countries, including Kenya, have ...

  10. 24 CFR 35.135 - Use of paint containing lead.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Use of paint containing lead. 35... Urban Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES General Lead-Based Paint Requirements and Definitions for All Programs. § 35.135 Use of paint containing lead. (a...

  11. Lead poisoning in ancient Rome | Retief | Acta Theologica

    African Journals Online (AJOL)

    Lead was known to the ancients from at least the 4th millennium BC, but its use increased markedly during Roman times, to the extent that it became a health hazard. Mines and foundry furnaces caused air pollution; lead was extensively used in plumbing; domestic utensils were made of lead and pewter, and lead salts ...

  12. [Study on lead absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Sun, Yong-Dong; Chen, Bi-Hua; Li, Xin-Zheng

    2008-07-01

    A study was carried out on the characteristic of lead absorption in pumpkin via atomic absorption spectrophotometer. The results showed that lead absorption amount in pumpkin increased with time, but the absorption rate decreased with time; And the lead absorption amount reached the peak in pH 7. Lead and cadmium have similar characteristic of absorption in pumpkin.

  13. Statistics and Epidemiology of Lead Poisoning (FY 72-L1).

    Science.gov (United States)

    Morrison, John H., Jr.; And Others

    This report is the first in a quarterly series which will contain statistics and epidemiologic notes on lead poisoning at both the national and local levels. This report contains (a) statistics on childhood lead poisoning; (b) a status report on the Community Lead Poisoning Data System, which was designed to assist local lead control programs and…

  14. Strategic Plan for the Elimination of Childhood Lead Poisoning.

    Science.gov (United States)

    Binder, Sue; Falk, Henry

    This document describes an agenda for the first 5 years of a comprehensive effort to eliminate childhood lead poisoning. In 1984, between 3 and 4 million children were estimated to have blood lead levels high enough to adversely affect intelligence and behavior. Lead in the home environment, especially lead-based paint, is the major source of lead…

  15. 40 CFR 141.84 - Lead service line replacement requirements.

    Science.gov (United States)

    2010-07-01

    ... PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and Copper § 141.84 Lead... portion would be precluded by State, local or common law. A water system that does not replace the entire...-replaced lead service line that is representative of the water in the service line for analysis of lead...

  16. 21 CFR 872.1850 - Lead-lined position indicator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lead-lined position indicator. 872.1850 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1850 Lead-lined position indicator. (a) Identification. A lead-lined position indicator is a cone-shaped device lined with lead that is attached to a...

  17. 49 CFR 192.471 - External corrosion control: Test leads.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Test leads. 192.471... Control § 192.471 External corrosion control: Test leads. (a) Each test lead wire must be connected to the pipeline so as to remain mechanically secure and electrically conductive. (b) Each test lead wire must be...

  18. Percutaneous extraction of transvenous permanent pacemaker/defibrillator leads.

    Science.gov (United States)

    Paraskevaidis, Stylianos; Konstantinou, Dimitrios; Vassilikos, Vassilios; Theofilogiannakos, Efstratios; Mantziari, Lilian; Megarisiotou, Athanasia; Galitsianos, Ioannis; Karvounis, Charalambos

    2014-01-01

    Widespread use of cardiovascular implantable electronic devices has inevitably increased the need for lead revision/replacement. We report our experience in percutaneous extraction of transvenous permanent pacemaker/defibrillator leads. Thirty-six patients admitted to our centre from September 2005 through October 2012 for percutaneous lead extraction were included. Lead removal was attempted using Spectranetics traction-type system (Spectranetics Corp., Colorado, CO, USA) and VascoExtor countertraction-type system (Vascomed GmbH, Weil am Rhein, Germany). Lead extraction was attempted in 59 leads from 36 patients (27 men), mean ± SD age 61 ± 5 years, with permanent pacemaker (n = 25), defibrillator (n = 8), or cardiac resynchronisation therapy (n = 3) with a mean ± SD implant duration of 50 ± 23 months. The indications for lead removal included pocket infection (n = 23), endocarditis (n = 2), and ventricular (n = 10) and atrial lead dysfunction (n = 1). Traction device was used for 33 leads and countertraction device for 26 leads. Mean ± SD fluoroscopy time was 4 ± 2 minutes/lead for leads implanted lead for leads implanted >48 months (n = 21), P = 0.03. Complete procedural success rate was 91.7% and clinical procedural success rate was 100%, while lead procedural success rate was 95%. In conclusion, percutaneous extraction of transvenous permanent pacemaker/defibrillator leads using dedicated removal tools is both feasible and safe.

  19. 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.

  20. Lead in women's and children's vitamins.

    Science.gov (United States)

    Mindak, William R; Cheng, John; Canas, Benjamin J; Bolger, P Michael

    2008-08-27

    A survey was conducted to determine the extent of lead (Pb) contamination in vitamins labeled for use by women and children. The Pb content of 324 multivitamin-mineral products was determined using microwave assisted nitric acid digestion and inductively coupled plasma mass spectrometry. Cryogenic grinding was used to composite soft samples such as oil filled capsules and candy-like products such as gummies and jelly beans. Estimates of Pb exposures from consumption of these products were derived for four population groups: young children (0-6 yrs), older children (7+ yrs), pregnant or lactating women, and adult women. The estimated median and maximum Pb exposures were 0.123 and 2.88 microg/day for young children, 0.356 and 1.78 microg/day for older children, 0.845 and 8.97 microg/day for pregnant and lactating women, and 0.842 and 4.92 microg/day for adult women. The overall median value for Pb exposure was 0.576 microg/day. Five samples would have provided exposures that exceeded 4 microg/day. Estimates of exposures were assessed with respect to safe/tolerable exposure levels that have been developed for the specific age and sex groups. These safe/tolerable levels are referred to as the provisional total tolerable intake levels (PTTI) and are 6, 15, 25, and 75 microg Pb/day for young children, older children, pregnant or lactating women, and adult women, respectively. Estimates of Pb exposures were below the PTTI levels for the four population groups. Median and maximum values were used instead of the mean and standard deviation because of the skewed distribution of results toward lower mass fraction and exposure.