Multiple causes of anaemia amongst children living near a lead smelter in Brazil

Energy Technology Data Exchange (ETDEWEB)

Carvalho, F M; Barreto, M L; Silvany-Neto, A M; Waldron, H A; Tavares, T M

1984-04-05

A prevalence study of anaemia was carried out amongst children, aged one to nine years, living near a lead smelter in Santo Amaro City, Northeast Brazil. It was found that the variation in haemoglobin levels was significantly associated with malnutrition and with the interaction between malnutrition and iron deficiency, but not with lead poisoning, iron deficiency, or hookworm infection, having allowed for the effects of age, area of residence, family per capita income and race. The effect of the interaction between malnutrition and iron deficiency on haemoglobin levels was most prominent amongst children aged one year and amongst those living in the most deprived area. The lack of demonstrable interaction between lead poisoning and iron deficiency in the causation of anaemia amongst these children is discussed.

Selective Sulfidation of Lead Smelter Slag with Sulfur

Science.gov (United States)

Han, Junwei; Liu, Wei; Wang, Dawei; Jiao, Fen; Qin, Wenqing

2016-02-01

The selective sulfidation of lead smelter slag with sulfur was studied. The effects of temperature, sulfur dosage, carbon, and Na salts additions were investigated based on thermodynamic calculation. The results indicated that more than 96 pct of zinc in the slag could be converted into sulfides. Increasing temperature, sulfur dosage, or Na salts dosage was conducive to the sulfidation of the zinc oxides in the slag. High temperature and excess Na salts would result in the more consumption of carbon and sulfur. Carbon addition not only promoted the selective sulfidation but reduced the sulfur dosage and eliminated the generation of SO2. Iron oxides had a buffering role on the sulfur efficient utilization. The transformation of sphalerite to wurtzite was feasible under reducing condition at high temperature, especially above 1273 K (1000 °C). The growth of ZnS particles largely depended upon the roasting temperature. They were significantly increased when the temperature was above 1273 K (1000 °C), which was attributed to the formation of a liquid phase.

Comparative results of copper flotation from smelter slag and granulated smelter slag

OpenAIRE

Milanović, Dragan; Stanujkić, Dragiša; Ignjatović, Miroslav R.

2013-01-01

Smelter slag is obtained in the process of metallurgical converting of copper concentrate in the Smelter Plant in Bor, Serbia. Today, the reserves of this material are evaluated at about more of a year, with the average copper content of 0.6-0.9%. Production of copper concentrate by flotation of smelter slag has started in 2001. Flotation concentrate goes to the Copper Smelter once more for production of copper cathodes and the rough flotation tailings go to the flotation tailing dump. Copper...

Decreasing emissions of a secondary lead smelter by installation of a battery breaker. Emissionsminderung einer Sekundaerbleihuette durch Integration einer Akkuschrott-Aufbereitung

Energy Technology Data Exchange (ETDEWEB)

Lamm, K F

1986-11-01

Dust and lead emissions of a secondary lead smelter mainly from the area of stockyards, handling, transport, charge preparing as well as the further treatment in rotary furnaces. A 60% decrease is obtained by compact assembling of covered battery stockyard, battery breaker and charge preparation and direct connection to the existing smelter area. The breaker itself contains a wet screen trommel and a filter press for separation of paste. The heavy-media sink-float-system has been replaced by dynamic water separation, which results in cleaner qualities of all fractions. In spite of a 100% wet separation plant, a bagfilter can be used with expected clean gas dust contents below 5 mg/m{sup 3} and below 2.5 mg Pb/m{sup 3}. Over a 2 years-period, dust and lead contents have been below 1 mg/m{sup 3}. (orig.) With 5 refs., 2 flowsheets, 10 figs.

Mapping airborne lead contamination near a metals smelter in Derbyshire, UK: spatial variation of Pb concentration and 'enrichment factor' for tree bark.

Science.gov (United States)

Bellis, D; Cox, A J; Staton, I; McLeod, C W; Satake, K

2001-10-01

Samples of tree bark, collected over an area of 4 km2 near a small non-ferrous metals smelter in Derbyshire, UK, were analysed for Pb and Al by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Analyte concentrations varied from 100 to over 25,000 mg kg-1 and 5 to 1000 mg kg-1, respectively. While an inverse relationship between the Pb content of bark and distance from the smelter was observed, concentrations fluctuated, indicating a variability in sample collection efficiency and problems in standardization. To overcome these effects, the Pb/Al ratio was calculated and subsequently normalized to the average Pb/Al ratio in continental crust (0.00015). On the assumption that the time-averaged concentration of airborne Al in this area is relatively constant and derived principally from wind-blown soil, the measurement represents an anthropogenic 'enrichment factor' (PbEF). PbEF varied from 10,000 to over 1,000,000, and showed a consistent reduction with distance from the smelter. Isolines of equal PbEF were subsequently defined on a map of the sampled area. Pb contamination was greatest in the vicinity of the smelter, and preferential transport along the NW-SE axis of the valley (in which the smelter is situated) was observed. The use of enrichment factors thus proved valuable in defining the relative level of airborne-derived Pb pollution.

Environmental lead exposure risks associated with children's outdoor playgrounds

International Nuclear Information System (INIS)

Taylor, Mark Patrick; Camenzuli, Danielle; Kristensen, Louise Jane; Forbes, Miriam; Zahran, Sammy

2013-01-01

This study examines exposure risks associated with lead smelter emissions at children's public playgrounds in Port Pirie, South Australia. Lead and other metal values were measured in air, soil, surface dust and on pre- and post-play hand wipes. Playgrounds closest to the smelter were significantly more lead contaminated compared to those further away (t(27.545) = 3.76; p = .001). Port Pirie post-play hand wipes contained significantly higher lead loadings (maximum hand lead value of 49,432 μg/m 2 ) than pre-play hand wipes (t(27) = 3.57, p = .001). A 1% increase in air lead (μg/m 3 ) was related to a 0.713% increase in lead dust on play surfaces (95% CI, 0.253–1.174), and a 0.612% increase in post-play wipe lead (95% CI, 0.257–0.970). Contaminated dust from smelter emissions is determined as the source and cause of childhood lead poisoning at a rate of approximately one child every third day. -- Highlights: •Spatial and temporal variations in lead exposure due to smelter emissions is examined. •Exposure to lead and other metals is evaluated using pre and post-play hand wipe measures. •The relationship of smelter emissions to surface and hand lead exposures is modelled. •A 1% increase in air lead (μg/m 3 ) was related to a 0.713% increase in lead dust on play surfaces. -- Playgrounds in Port Pirie are seriously contaminated by smelter emissions, with levels of surface dust and hand dust that pose a significant risk of harm to human health

The effect of the hemochromatosis (HFE) genotype on lead load and iron metabolism among lead smelter workers.

Science.gov (United States)

Fan, Guangqin; Du, Guihua; Li, Huijun; Lin, Fen; Sun, Ziyong; Yang, Wei; Feng, Chang; Zhu, Gaochun; Li, Yanshu; Chen, Ying; Jiao, Huan; Zhou, Fankun

2014-01-01

Both an excess of toxic lead (Pb) and an essential iron disorder have been implicated in many diseases and public health problems. Iron metabolism genes, such as the hemochromatosis (HFE) gene, have been reported to be modifiers for lead absorption and storage. However, the HFE gene studies among the Asian population with occupationally high lead exposure are lacking. To explore the modifying effects of the HFE genotype (wild-type, H63D variant and C282Y variant) on the Pb load and iron metabolism among Asian Pb-workers with high occupational exposure. Seven hundred and seventy-one employees from a lead smelter manufacturing company were tested to determine their Pb intoxication parameters, iron metabolic indexes and identify the HFE genotype. Descriptive and multivariate analyses were conducted. Forty-five H63D variant carriers and no C282Y variant carrier were found among the 771 subjects. Compared with subjects with the wild-type genotype, H63D variant carriers had higher blood lead levels, even after controlling for factors such as age, sex, marriage, education, smoking and lead exposure levels. Multivariate analyses also showed that the H63D genotype modifies the associations between the blood lead levels and the body iron burden/transferrin. No C282Y variant was found in this Asian population. The H63D genotype modified the association between the lead and iron metabolism such that increased blood lead is associated with a higher body iron content or a lower transferrin in the H63D variant. It is indicated that H63D variant carriers may be a potentially highly vulnerable sub-population if they are exposed to high lead levels occupationally.

Heavy metals in white-tailed deer living near a zinc smelter in Pennsylvania

Science.gov (United States)

Sileo, Louis; Beyer, W. Nelson

1985-01-01

White-tailed deer (Odocoileus virginianus (Zimmermann)) shot within 20 km of the zinc smelters in the Palmerton, Pennsylvania area contained extremely high renal concentrations of cadmium (372 ppm dry weight (dw)) and zinc (600 ppm dw). The deer with the highest renal zinc concentration was shot 4 km from the smelters and had joint lesions similar to those seen in zinc-poisoned horses from the same area. The highest concentrations of lead in both hard and soft tissues were relatively low, 10.9 ppm dw in a sample of teeth, 17.4 ppm dw in a metacarpus, and 4.9 ppm dw in a kidney.

Contamination and health risks of soil heavy metals around a lead/zinc smelter in southwestern China.

Science.gov (United States)

Li, Peizhong; Lin, Chunye; Cheng, Hongguang; Duan, Xiaoli; Lei, Kai

2015-03-01

Anthropogenic emissions of toxic metals from smelters are a global problem. The objective of this study was to investigate the distribution of toxic metals in soils around a 60 year-old Pb/Zn smelter in a town in Yunnan Province of China. Topsoil and soil core samples were collected and analyzed to determine the concentrations of various forms of toxic metals. The results indicated that approximately 60 years of Pb/Zn smelting has led to significant contamination of the local soil by Zn, Pb, Cd, As, Sb, and Hg, which exhibited maximum concentrations of 8078, 2485, 75.4, 71.7, 25.3, and 2.58mgkg(-1), dry wet, respectively. Other metals, including Co, Cr, Cu, Mn, Ni, Sc, and V, were found to originate from geogenic sources. The concentrations of smelter driven metals in topsoil decreased with increasing distance from the smelter. The main contamination by Pb, Zn, and Cd was found in the upper 40cm of soil around the Pb/Zn smelter, but traces of Pb, Zn, and Cd contamination were found below 100cm. Geogenic Ni in the topsoil was mostly bound in the residual fraction (RES), whereas anthropogenic Cd, Pb, and Zn were mostly associated with non-RES fractions. Therefore, the smelting emissions increased not only the concentrations of Cd, Pb, and Zn in the topsoil but also their mobility and bioavailability. The hazard quotient and hazard index showed that the topsoil may pose a health risk to children, primarily due to the high Pb and As contents of the soil. Copyright © 2014 Elsevier Inc. All rights reserved.

Heavy metal content of lichens in relation to distance from a nickel smelter in Sudbury, Ontario

Energy Technology Data Exchange (ETDEWEB)

Nieboer, E; Ahmed, H M; Puckett, K J; Richardson, D H.S.

1972-01-01

The Sudbury region of Ontario has large deposits of nickel, iron, and copper, and thus a number of smelting plants which produce sulfur dioxide and heavy metal pollution. Since lichens are good indicators of SO/sub 2/ pollution levels, the pattern of heavy metal content in lichen species in the area of a copper smelter in Sudbury was correlated with distance from the smelter to ascertain whether lichens might also be good indicators of the amount of heavy metal fallout. The lichens were analyzed qualitatively and quantitatively. All seven species of lichens contained copper, iron, zinc, nickel, manganese, and lead. Cadmium and cobalt were detected in two species. Neither gold nor silver could be identified in lichen material with the tests used. A pollution model was developed and compared to field results. The simple dilution of the stack effluent was consistent with the fact that the lichen metal content was related to the reciprocal of the distance from the pollution source. The lichens from the area could tolerate simultaneously high concentrations of several heavy metals that are known to be toxic to other plants. The mechanism of metal uptake was not clearly established. The study showed that lichens and other epiphytes are potentially the most useful indicators of heavy metal fallout around industrial plants.

The effect of the hemochromatosis (HFE genotype on lead load and iron metabolism among lead smelter workers.

Directory of Open Access Journals (Sweden)

Guangqin Fan

Full Text Available Both an excess of toxic lead (Pb and an essential iron disorder have been implicated in many diseases and public health problems. Iron metabolism genes, such as the hemochromatosis (HFE gene, have been reported to be modifiers for lead absorption and storage. However, the HFE gene studies among the Asian population with occupationally high lead exposure are lacking.To explore the modifying effects of the HFE genotype (wild-type, H63D variant and C282Y variant on the Pb load and iron metabolism among Asian Pb-workers with high occupational exposure.Seven hundred and seventy-one employees from a lead smelter manufacturing company were tested to determine their Pb intoxication parameters, iron metabolic indexes and identify the HFE genotype. Descriptive and multivariate analyses were conducted.Forty-five H63D variant carriers and no C282Y variant carrier were found among the 771 subjects. Compared with subjects with the wild-type genotype, H63D variant carriers had higher blood lead levels, even after controlling for factors such as age, sex, marriage, education, smoking and lead exposure levels. Multivariate analyses also showed that the H63D genotype modifies the associations between the blood lead levels and the body iron burden/transferrin.No C282Y variant was found in this Asian population. The H63D genotype modified the association between the lead and iron metabolism such that increased blood lead is associated with a higher body iron content or a lower transferrin in the H63D variant. It is indicated that H63D variant carriers may be a potentially highly vulnerable sub-population if they are exposed to high lead levels occupationally.

The conjoint influence of home enriched environment and lead exposure on children's cognition and behaviour in a Mexican lead smelter community.

Science.gov (United States)

Moodie, Sue; Ialongo, Nick; López, Patricia; Rosado, Jorge; García-Vargas, Gonzalo; Ronquillo, Dolores; Kordas, Katarzyna

2013-01-01

A range of studies has been conducted on the detrimental effects of lead in mining and smelting communities. The neurocognitive and behavioural health effects of lead on children are well known. This research characterized the conjoint influence of lead exposure and home enriched environment on neurocognitive function and behaviour for first-grade children living in a Mexican lead smelter community. Structural equation models were used for this analysis with latent outcome variables, Cognition and Behaviour, constructed based on a battery of assessments administered to the first-grade children, their parents, and teachers. Structural equation modelling was used to describe complex relationships of exposure and health outcomes in a manner that permitted partition of both direct and indirect effects of the factors being measured. Home Environment (a latent variable constructed from information on mother's education and support of school work and extracurricular activities), and child blood lead concentration each had a main significant effect on cognition and behaviour. However, there were no statistically significant moderation relationships between lead and Home Environment on these latent outcomes. Home Environment had a significant indirect mediation effect between lead and both Cognition and Behaviour (p-valueEnvironment has a moderate mediation effect with respect to lead effects on Behaviour (β=0.305) and a lower mediation effect on Cognition (β=0.184). The extent of home enrichment in this study was most highly related to the mother's support of schoolwork and slightly less by the mother's support of extracurricular activities or mother's education. Further research may be able to develop approaches to support families to make changes within their home and child rearing practices, or advocate for different approaches to support their child's behaviour to reduce the impact of lead exposure on children's cognitive and behavioural outcomes. Copyright © 2012

Arsenic pollution in the Yellowknife area from gold smelter activities

International Nuclear Information System (INIS)

Hutchinson, T.C.; Aufreiter, S.; Hancock, R.G.V.

1982-01-01

Gold mined at Yelloknife in the North West Territories of Canada is associated with arsenopyrite ores which necessitates the oxidation of the arsenic and sulphur by roasting at two Yellowknife smelters. As 2 O 3 and SO 2 are emitted into the atmosphere, and despite improvements in emission control, significant emissions still occur. In order to asses the arsenic contamination in the local environment and the potential exposures to man, soil samples and samples of the native vegetation were collected in and around Yellowknife and the two smelters. Arsenic and antimony analyses were done by instrumental neutron activation analysis using the SLOWPOKE facility at University of Toronto. Zinc, copper, lead and cadmium analyses were done by atomic adsorption spectrophotometry. Arsenic was found to be accumulated in the soils in the vicinity of the two smelters to levels of several thousand ppm. Antimony levels were about 10% of arsenic and were highly correlated with arsenic. Zinc occured to 500 ppm around the smelters. Soil arsenic levels are sufficiently high to inhibit root growth in soils over a very extensive area. (author)

Soil microbial effects of smelter induced heavy metal contamination

Energy Technology Data Exchange (ETDEWEB)

Nordgren, A

1986-01-01

The soil concentrations of Cu and Zn at the secondary smelter were 20 00 mu g/g dry soil. Close to the primary smelter the soil was contaminated with more than ten elements including Pb, Zn, Cu and As at levels ranging between 6000 and 1000 mu g/g dry soil. The correlations between the concentrations of the metals were high at both smelters. Soil respiration rate decreased by about 75% close to both smelters. Total and fluorescein diacetate stained mycelial lengths decrease with increasing heavy metal pollution at the secondary but not at the primary smelter. The fungal community structure was strongly affected by the contamination. General common in coniferous forest soils such as Penicillium and Oidiodendron virtually vanished, while less frequent species like Paecilomyces farinosus and Geomyces pannorum dominated the site close to the smelter. Colony forming units of a number of functional groups of bacteria were found to be very sensitive to metal contamination. The urease activity of the soil was inhibited. Multivariate statistical analyses showed that the metal contamination was the major environmental influence on the microbiotain the soils studied. A study of about 200 decomposition curves resulting from glutamic acid additions to the different soils produced four microbially related parameters: basal respiration rate, initial respiration rate after the addition of the glutamic acid, specific respiration rate during the exponential increase of the respiration rate and the lag time before the exponential phase. With 53 refs.

Generic assessment of radiation exposures to workers in a portable smelter and to the surrounding population

International Nuclear Information System (INIS)

Randolph, M.L.; Watson, A.P.; O'Donnell, F.R.

1978-10-01

A scenario for operation of a proposed portable smelter has been developed by National Lead Company of Ohio to recycle radioactively contaminated ferrous scrap arising from modifications at nuclear facilities of the Department of Energy. The current generic study complements that work by developing tables of radiation dose conversion factors for estimation of external whole-body doses and 50-year whole-body internal dose commitments to routine workers in the smelter and to the public within 50 miles of the smelter. Applications of the tables to specific cases require site-specific source terms consisting of amounts of radionuclides present in scrap metal, separation efficiency for radionuclides, concentration of contaminated airborne particulates, ingested amount of contaminated material, and amount of metal released through the stack. Equations relating doses to tabular values and these source terms are developed, and hypothetical sample calculations are given. Assumptions, approximations, and limitations of the methods are discussed as well as nonroutine operations and nonradioactive hazards

Use of neutron activation analysis to determine arsenic and antimony concentrations in creosote bushes collected near a lead smelter in El Paso, Texas

International Nuclear Information System (INIS)

Gardea-Torresdey, J.; Tiemann, K.J.; Parsons, J.G.; Landsberger, S.; O'Kelly, D.

2001-01-01

It his been found that some soils adjacent to a lead smelter in El Paso, Texas possess lead and copper concentrations as high as 5,067 mg/kg (parts per million) and 4,955 mg/kg, respectively. These concentrations are at least one order of magnitude higher than naturally occurring levels. The objective of this work is to determine the amount of metal accumulation within creosote bush, as it is found naturally growing in metal contaminated soils through analysis of soil and plant tissue samples. (R.P.)

Estimating mercury emissions from a zinc smelter in relation to China's mercury control policies

International Nuclear Information System (INIS)

Wang, S.X.; Song, J.X.; Li, G.H.; Wu, Y.; Zhang, L.; Wan, Q.; Streets, D.G.; Chin, Conrad K.; Hao, J.M.

2010-01-01

Mercury concentrations of flue gas at inlet/outlet of the flue gas cleaning, electrostatic demister, reclaiming tower, acid plant, and mercury contents in zinc concentrate and by-products were measured in a hydrometallurgical zinc smelter. The removal efficiency of flue gas cleaning, electrostatic demister, mercury reclaiming and acid plant was about 17.4%, 30.3%, 87.9% and 97.4% respectively. Flue gas cleaning and electrostatic demister captured 11.7% and 25.3% of the mercury in the zinc concentrate, respectively. The mercury reclaiming tower captured 58.3% of the mercury in the zinc concentrate. About 4.2% of the mercury in the zinc concentrate was captured by the acid plant. Consequently, only 0.8% of the mercury in the zinc concentrate was emitted to the atmosphere. The atmospheric mercury emission factor was 0.5 g t -1 of zinc produced for the tested smelter, indicating that this process offers the potential to effectively reduce mercury emissions from zinc smelting. - Modern scale production equipped with acid plant and Hg reclaiming tower will significantly reduce Hg emissions from zinc smelters in China.

Integrating science and business models of sustainability for environmentally-challenging industries such as secondary lead smelters: a systematic review and analysis of findings.

Science.gov (United States)

Genaidy, A M; Sequeira, R; Tolaymat, T; Kohler, J; Wallace, S; Rinder, M

2010-09-01

Secondary lead smelters (SLS) represent an environmentally-challenging industry as they deal with toxic substances posing potential threats to both human and environmental health, consequently, they operate under strict government regulations. Such challenges have resulted in the significant reduction of SLS plants in the last three decades. In addition, the domestic recycling of lead has been on a steep decline in the past 10 years as the amount of lead recovered has remained virtually unchanged while consumption has increased. Therefore, one may wonder whether sustainable development can be achieved among SLS. The primary objective of this study was to determine whether a roadmap for sustainable development can be established for SLS. The following aims were established in support of the study objective: (1) to conduct a systematic review and an analysis of models of sustainable systems with a particular emphasis on SLS; (2) to document the challenges for the U.S. secondary lead smelting industry; and (3) to explore practices and concepts which act as vehicles for SLS on the road to sustainable development. An evidence-based methodology was adopted to achieve the study objective. A comprehensive electronic search was conducted to implement the aforementioned specific aims. Inclusion criteria were established to filter out irrelevant scientific papers and reports. The relevant articles were closely scrutinized and appraised to extract the required information and data for the possible development of a sustainable roadmap. The search process yielded a number of research articles which were utilized in the systematic review. Two types of models emerged: management/business and science/mathematical models. Although the management/business models explored actions to achieve sustainable growth in the industrial enterprise, science/mathematical models attempted to explain the sustainable behaviors and properties aiming at predominantly ecosystem management. As such

Controls on Metal Leaching from Secondary Pb Smelter Air-Pollution-Control Residues

Czech Academy of Sciences Publication Activity Database

Ettler, V.; Šebek, O.; Grygar, Tomáš; Klementová, Mariana; Bezdička, Petr

2008-01-01

Roč. 42, č. 21 (2008), s. 7878-7884 ISSN 0013-936X Institutional research plan: CEZ:AV0Z40320502 Keywords : lead smelter * waste incineration * soils Subject RIV: CA - Inorganic Chemistry Impact factor: 4.458, year: 2008

Particle size distributions of lead measured in battery manufacturing and secondary smelter facilities and implications in setting workplace lead exposure limits.

Science.gov (United States)

Petito Boyce, Catherine; Sax, Sonja N; Cohen, Joel M

2017-08-01

Inhalation plays an important role in exposures to lead in airborne particulate matter in occupational settings, and particle size determines where and how much of airborne lead is deposited in the respiratory tract and how much is subsequently absorbed into the body. Although some occupational airborne lead particle size data have been published, limited information is available reflecting current workplace conditions in the U.S. To address this data gap, the Battery Council International (BCI) conducted workplace monitoring studies at nine lead acid battery manufacturing facilities (BMFs) and five secondary smelter facilities (SSFs) across the U.S. This article presents the results of the BCI studies focusing on the particle size distributions calculated from Personal Marple Impactor sampling data and particle deposition estimates in each of the three major respiratory tract regions derived using the Multiple-Path Particle Dosimetry model. The BCI data showed the presence of predominantly larger-sized particles in the work environments evaluated, with average mass median aerodynamic diameters (MMADs) ranging from 21-32 µm for the three BMF job categories and from 15-25 µm for the five SSF job categories tested. The BCI data also indicated that the percentage of lead mass measured at the sampled facilities in the submicron range (i.e., lead) was generally small. The estimated average percentages of lead mass in the submicron range for the tested job categories ranged from 0.8-3.3% at the BMFs and from 0.44-6.1% at the SSFs. Variability was observed in the particle size distributions across job categories and facilities, and sensitivity analyses were conducted to explore this variability. The BCI results were compared with results reported in the scientific literature. Screening-level analyses were also conducted to explore the overall degree of lead absorption potentially associated with the observed particle size distributions and to identify key issues

Impact of Site Elevation on Mg Smelter Design

Science.gov (United States)

Baker, Phillip W.

Site elevation has many surprising and significant impacts on the engineering design of metallurgical plant of all types. Electrolytic magnesium smelters maybe built at high elevation for a variety of reasons including availability of raw material, energy or electric power. Because of the unit processes they typically involve, Mg smelters can be extensively impacted by site elevation. In this paper, generic examples of the design changes required to adapt a smelter originally designed for sea level to operate at 2700 m are presented. While the examples are drawn from a magnesium plant design case, these changes are generically applicable to all industrial plants utilizing similar unit processes irrespective of product.

Long term insight into biodiversity of a smelter wasteland reclaimed with biosolids and by-product lime.

Science.gov (United States)

Siebielec, Sylwia; Siebielec, Grzegorz; Stuczyński, Tomasz; Sugier, Piotr; Grzęda, Emilia; Grządziel, Jarosław

2018-09-15

Smelter wastelands containing high amounts of zinc, lead, cadmium, and arsenic constitute a major problem worldwide. Serious hazards for human health and ecosystem functioning are related to a lack of vegetative cover, causing fugitive dust fluxes, runoff and leaching of metals, affecting post-industrial ecosystems, often in heavily populated areas. Previous studies demonstrated the short term effectiveness of assisted phytostabilisation of zinc and lead smelter slags, using biosolids and liming. However, a long term persistence of plant communities introduced for remediation and risk reduction has not been adequately evaluated. The work was aimed at characterising trace element solubility, plant and microbial communities of the top layer of the reclaimed zinc and lead smelter waste heaps in Piekary Slaskie, Poland, 20 years after the treatment and revegetation. The surface layer of the waste heaps treated with various rates of biosolids and the by-product lime was sampled for measuring chemical and biochemical parameters, which are indicative for metals bioavailability as well as for microorganisms activity. Microbial processes were characterised by enzyme activities, abundance of specific groups of microorganisms and identification of N fixing bacteria. Plant communities of the area were characterised by a percent coverage of the surface and by a composition of plant species and plant diversity. The study provides a strong evidence that the implemented remediation approach enables a sustainable functioning of the ecosystem established on the toxic waste heaps. Enzyme activities and the count of various groups of microorganisms were the highest in areas treated with both biosolids and lime, regardless their rates. A high plant species diversity and microbial activities are sustainable after almost two decades from the treatment, which is indicative of a strong resistance of the established ecosystem to a metal stress and a poor physical quality of the

Catchment liming creates recolonization opportunity for sensitive invertebrates in a smelter impacted landscape

Directory of Open Access Journals (Sweden)

John M. Gunn

2016-04-01

Full Text Available The response of a sensitive indicator species to the effects of catchment liming was assessed in a lake severely impacted by atmospheric emissions from a metal smelter in Sudbury, Canada. The lake chemistry recovered following the closure of the local smelter and major reductions (approximately 95% in acid and metal emissions from other area smelters, leading to recolonization of the lake with fish and other biota. However, the littoral macrobenthos community remain severely impoverished. The catchment liming sustained improved stream water quality for 20 years after the initial aerial treatment and created a littoral zone hot spot for the recolonization of Hyalella azteca. Colonization at delta sites of untreated catchment drainage areas, in the same lake, were low and highly variable, and these sites appeared to be impacted from soil erosion and episodic release of acid and metals. This study demonstrated the need to both reduce air pollutants and to conduct land reclamation in severely damaged watersheds, before lake ecosystems themselves can be fully recovered.

Mercury deposition/accumulation rates in the vicinity of a lead smelter as recorded by a peat deposit

Czech Academy of Sciences Publication Activity Database

Ettler, V.; Navrátil, Tomáš; Mihaljevič, M.; Rohovec, Jan; Zuna, M.; Šebek, O.; Strnad, L.; Hojdová, Maria

2008-01-01

Roč. 42, č. 24 (2008), s. 5968-5977 ISSN 1352-2310 R&D Projects: GA ČR GP526/07/P170 Institutional research plan: CEZ:AV0Z30130516 Keywords : mercury * deposition * Pb Smelter, * peat * historical record Subject RIV: DD - Geochemistry Impact factor: 2.890, year: 2008

Exposure to Fluoride in Smelter Workers in a Primary Aluminum Industry in India

Directory of Open Access Journals (Sweden)

AK Susheela

2013-04-01

Full Text Available Background: Fluoride is used increasingly in a variety of industries in India. Emission of fluoride dust and fumes from the smelters of primary aluminum producing industries is dissipated in the work environment and poses occupational health hazards. Objective: To study the prevalence of health complaints and its association with fluoride level in body fluids of smelter workers in a primary aluminum producing industry. Methods: In an aluminum industry, health status of 462 smelter workers, 60 supervisors working in the smelter unit, 62 non-smelter workers (control group 1 and 30 administration staff (control group 2 were assessed between 2007 and 2009. Their health complaints were recorded and categorized into 4 groups: 1 gastro-intestinal complaints; 2 non-skeletal manifestations; 3 skeletal symptoms; and (4 respiratory problems. Fluoride level in body fluids, nails, and drinking water was tested by an ion selective electrode; hemoglobin level was tested using HemoCue. Results: The total complaints reported by study groups were significantly higher than the control groups. Smelter workers had a significantly (p<0.001 higher urinary and serum fluoride level than non-smelter workers; the nail fluoride content was also higher in smelter workers than non-smelter workers (p<0.001. The smelter workers with higher hemoglobin level had a significantly (p<0.001 lower urinary fluoride concentration and complained less frequently of health problems. Only 1.4% of the smelter workers were consuming water with high fluoride concentrations. A high percentage of participants was using substances with high fluoride contents. Conclusions: Industrial emission of fluoride is not the only important sources of fluoride exposure—consumption of substance with high levels of fluoride is another important route of entry of fluoride into the body. Measurement of hemoglobin provides a reliable indicator for monitoring the health status of employees at risk of fluorosis.

Spatial clustering of toxic trace elements in adolescents around the Torreón, Mexico lead–zinc smelter

Science.gov (United States)

Garcia-Vargas, Gonzalo G.; Rothenberg, Stephen J.; Silbergeld, Ellen K.; Weaver, Virginia; Zamoiski, Rachel; Resnick, Carol; Rubio-Andrade, Marisela; Parsons, Patrick J.; Steuerwald, Amy J.; Navas-Acién, Ana; Guallar, Eliseo

2016-01-01

High blood lead (BPb) levels in children and elevated soil and dust arsenic, cadmium, and lead were previously found in Torreón, northern Mexico, host to the world’s fourth largest lead–zinc metal smelter. The objectives of this study were to determine spatial distributions of adolescents with higher BPb and creatinine-corrected urine total arsenic, cadmium, molybdenum, thallium, and uranium around the smelter. Cross-sectional study of 512 male and female subjects 12–15 years of age was conducted. We measured BPb by graphite furnace atomic absorption spectrometry and urine trace elements by inductively coupled plasma-mass spectrometry, with dynamic reaction cell mode for arsenic. We constructed multiple regression models including sociodemographic variables and adjusted for subject residence spatial correlation with spatial lag or error terms. We applied local indicators of spatial association statistics to model residuals to identify hot spots of significant spatial clusters of subjects with higher trace elements. We found spatial clusters of subjects with elevated BPb (range 3.6–14.7 µg/dl) and urine cadmium (0.18–1.14 µg/g creatinine) adjacent to and downwind of the smelter and elevated urine thallium (0.28–0.93 µg/g creatinine) and uranium (0.07–0.13 µg/g creatinine) near ore transport routes, former waste, and industrial discharge sites. The conclusion derived from this study was that spatial clustering of adolescents with high BPb and urine cadmium adjacent to and downwind of the smelter and residual waste pile, areas identified over a decade ago with high lead and cadmium in soil and dust, suggests that past and/or present plant operations continue to present health risks to children in those neighborhoods. PMID:24549228

Mortality study of lead workers

Energy Technology Data Exchange (ETDEWEB)

Cooper, W C; Gaffey, W R

1975-01-01

The mortality of 7,032 men employed for one or more years in lead production facilities or battery plants was followed over a 23-year period, 1947-70. Lead absorption in many of these men was greatly in excess of currently accepted standards based upon urinary and blood lead concentrations available for a portion of the group. There were 1,356 deaths reported. The standardized mortality ratio (SMR) for all causes was 107 for smelter workers and 99 for battery plant workers. Death from neoplasms were in slight excess in smelters, but not significantly increased in battery plants. There were no excess deaths from kidney tumors. The SMR for cardiovascular-renal disease was 96 for smelter workers and 101 for battery plant workers. There was definitely no excess in deaths from either stroke or hypertensive heart disease; however, deaths classified as other hypertensive disease and unspecified nephritis or renal sclerosis were higher than expected. The life expectancy of lead workers was calculated to be approximately the same as that of all U.S. males.

Exposure to fluoride in smelter workers in a primary aluminum industry in India.

Science.gov (United States)

Susheela, A K; Mondal, N K; Singh, A

2013-04-01

Fluoride is used increasingly in a variety of industries in India. Emission of fluoride dust and fumes from the smelters of primary aluminum producing industries is dissipated in the work environment and poses occupational health hazards. To study the prevalence of health complaints and its association with fluoride level in body fluids of smelter workers in a primary aluminum producing industry. In an aluminum industry, health status of 462 smelter workers, 60 supervisors working in the smelter unit, 62 non-smelter workers (control group 1) and 30 administration staff (control group 2) were assessed between 2007 and 2009. Their health complaints were recorded and categorized into 4 groups: 1) gastro-intestinal complaints; 2) non-skeletal manifestations; 3) skeletal symptoms; and (4) respiratory problems. Fluoride level in body fluids, nails, and drinking water was tested by an ion selective electrode; hemoglobin level was tested using HemoCue. The total complaints reported by study groups were significantly higher than the control groups. Smelter workers had a significantly (pworkers; the nail fluoride content was also higher in smelter workers than non-smelter workers (pworkers with higher hemoglobin level had a significantly (pworkers were consuming water with high fluoride concentrations. A high percentage of participants was using substances with high fluoride contents. Industrial emission of fluoride is not the only important sources of fluoride exposure--consumption of substance with high levels of fluoride is another important route of entry of fluoride into the body. Measurement of hemoglobin provides a reliable indicator for monitoring the health status of employees at risk of fluorosis.

Improved dust handling at Inco's Copper Cliff smelter

International Nuclear Information System (INIS)

Dutton, A.; Warner, A.E.M.; Humphris, M.J.

1989-01-01

The Cooper Cliff Smelter Complex comprises three major production departments - a Nickel Smelter for the processing of nickel concentrated to a low iron, nickel - copper sulphide (Bessemer) matte; a Matte Processing plant for the separation of matte sulphides and the production of market nickel oxides and refinery feeds and a Copper Smelter to process copper concentrates to blister copper. Annual production is currently -114,000 tonnes of copper as blister and -110,000 tonnes of nickel. The nickel concentrate (11-13% Ni, 2-3% Cu) is roasted in multi-hearth roasters, smelted in oxy-fuel fired reverberatory furnaces to a 30-35% CuNiCo matte and converted to Bessemer matte (75% CuNiCo) in Peirce-Smith converters. The Bessemer matte is slow cooled and crushed for subsequent separation by mineral dressing techniques in the Matte Processing plant into nickel (sulphide and metallic) concentrates and a copper (chalcocite) concentrate. Nickel sulphides are further processed in fluid bed reactors to oxide market product or refinery feedstock. The copper concentrate (29-30% Cu, 0.9% No.) is dried in fluid bed driers, smelted to a 40-50% copper matte in an Inco oxygen flash furnace and converted to blister copper in Peirce-Smith converters. The chalcocite concentrate from the matte separation stage is flash converted to a semi-blister (3-4% S, 4-5% Ni) and then finished to lighter conventionally. A schematic process flowsheet of the Smelter Complex is shown in this paper

Antimony distribution and environmental mobility at an historic antimony smelter site, New Zealand

International Nuclear Information System (INIS)

Wilson, N.J.; Craw, D.; Hunter, K.

2004-01-01

A historic antimony smelter site at Endeavour Inlet, New Zealand has smelter residues with up to 17 wt.% antimony. Residues include coarse tailings (cm scale particles, poorly sorted), sand tailings (well sorted) and smelter slag (blocks up to 30 cm across). All of this material has oxidised to some degree over the ca. 100 years since the site was abandoned. Oxidation has resulted in acidification of the residues down to pH 2-5. Smelter slag contains pyrrhotite (FeS) and metallic antimony, and oxidation is restricted to surfaces only. The coarse tailings are the most oxidised, and few sulfide grains persist. Unoxidised sand tailings contain 10-20 vol.% stibnite (Sb 2 S 3 ) containing up to 5% As, with subordinate arsenopyrite (FeAsS), and minor pyrite (FeS 2 ). The sand tailings are variably oxidised on a scale of 2-10 cm, but original depositional layering is preserved during oxidation and formation of senarmontite (Sb 2 O 3 ). Oxidation of sand tailings has resulted in localised mobility of both Sb and As on the cm scale, resulting in redistribution of these metalloids with iron oxyhydroxide around sand grain boundaries. Experiments demonstrate that Sb mobility decreases with time on a scale of days. Attenuation of both As and Sb occurs due to adsorption on to iron oxyhydroxides which are formed during oxidation of the smelter residues. There is no detectable loss of Sb or As from the smelter site into the adjacent river, <50 m away, which has elevated Sb (ca. 20 μg/l) and As (ca. 7 μg /l) from mineralised rocks upstream. Despite the high concentrations of Sb and As in the smelter residues, these metalloids are not being released into the environment. - High levels of antimony in primitive smelter soils remain largely immobile on the metre scale

76 FR 64943 - Proposed Cercla Administrative Cost Recovery Settlement; ACM Smelter and Refinery Site, Located...

Science.gov (United States)

2011-10-19

... Settlement; ACM Smelter and Refinery Site, Located in Cascade County, MT AGENCY: Environmental Protection... projected future response costs concerning the ACM Smelter and Refinery NPL Site (Site), Operable Unit 1..., Helena, MT 59626. Mr. Sturn can be reached at (406) 457-5027. Comments should reference the ACM Smelter...

Feasibility study of a portable smelter for scrap metals

International Nuclear Information System (INIS)

Cavendish, J.H.

1976-06-01

The use of a portable smelter to process uranium-contaminated scrap metals was studied. Objectives were to convert scrap metal located at many diverse sites into a form which would be suitable for unlicensed sale and reduce the problems associated with storing the scrap. The Foundry Design Company study indicated the portable smelter concept was feasible from an equipment and transportation standpoint. Capital costs for a 5-ton/hour (steel) nominal capacity unit were estimated to be $2,349,000. Technical evaluation indicates that all the common metals considered, i.e., iron, nickel, copper, and aluminum, are amenable to uranium decontamination by smelting except aluminum. An economic evaluation of the processing of the 30,000 tons of steel scrap to be generated by the Cascade Improvement Program by a portable smelter was made based upon information supplied by Foundry Design Company, plus the assumption that the product metal could be sold for $120.00 per ton. This evaluation indicated a net return of $2,424,000 to the government could be realized. The Health and Safety study indicated no major problems of this nature would be encountered in operating a portable smelter. The legal review indicated the proposed operation fell within the authority of existing regulations. Consideration of possible conflicts with regard to competition with the private sector was suggested

The influence of the intensity of smoking and years of work in the metallurgy on pro-oxidant/antioxidant balance in the blood of smelters.

Science.gov (United States)

Bizon, Anna; Antonowicz-Juchniewicz, Jolanta; Andrzejak, Ryszard; Milnerowicz, Halina

2013-03-01

The aim of this study was to investigate the effect of cigarette smoking and occupational exposure to heavy metals on the degree of pro-oxidant/antioxidant imbalance in smelters. The investigations were performed on the blood and urine of 400 subjects: 300 male copper smelters and 100 nonexposed male subjects. Biological material was divided into three groups: nonsmokers, those who smoked less than 20 cigarettes a day and those who smoked more than 20 cigarettes a day. The results showed a significant increase in the concentration of lead, cadmium and arsenic in the blood and urine of smelters, while smoking more than 20 cigarettes a day caused a further increase in the concentration of these metals. The level of malondialdehyde was approximately twofold higher in the plasma of the smelters compared to the control group. We have observed a disturbance in the level of antioxidants in erythrocyte lysate manifested by an increase in metallothionein and glutathione concentrations as well as superoxide dismutase and glutathione peroxidase activities and the decrease in glutathione S-transferase activity. Cigarette smoking, years of work in metallurgy and age of smelters were additional factors significantly affecting the pro-oxidant/antioxidant balance.

Bioavailability and uptake of smelter emissions in freshwater zooplankton in northeastern Washington, USA lakes using Pb isotope analysis and trace metal concentrations.

Science.gov (United States)

Child, A W; Moore, B C; Vervoort, J D; Beutel, M W

2018-07-01

The upper Columbia River and associated valley systems are highly contaminated with metal wastes from nearby smelting operations in Trail, British Columbia, Canada (Teck smelter), and to a lesser extent, Northport, Washington, USA (Le Roi smelter). Previous studies have investigated depositional patterns of airborne emissions from these smelters, and documented the Teck smelter as the primary metal contamination source. However, there is limited research directed at whether these contaminants are bioavailable to aquatic organisms. This study investigates whether smelter derived contaminants are bioavailable to freshwater zooplankton. Trace metal (Zn, Cd, As, Sb, Pb and Hg) concentrations and Pb isotope compositions of zooplankton and sediment were measured in lakes ranging from 17 to 144 km downwind of the Teck smelter. Pb isotopic compositions of historic ores used by both smelters are uniquely less radiogenic than local geologic formations, so when zooplankton assimilate substantial amounts of smelter derived metals their compositions deviate from local baseline compositions toward ore compositions. Sediment metal concentrations and Pb isotope compositions in sediment follow significant (p < 0.001) negative exponential and sigmoidal patterns, respectively, as distance from the Teck smelting operation increases. Zooplankton As, Cd, and Sb contents were related to distance from the Teck smelter (p < 0.05), and zooplankton Pb isotope compositions suggest As, Cd, Sb and Pb from historic and current smelter emissions are biologically available to zooplankton. Zooplankton from lakes within 86 km of the Teck facility display isotopic evidence that legacy ore pollution is biologically available for assimilation. However, without water column data our study is unable to determine if legacy contaminants are remobilized from lake sediments, or erosional pathways from the watershed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Selecting an oxygen plant for a copper smelter modernization

Science.gov (United States)

Larson, Kenneth H.; Hutchison, Robert L.

1994-10-01

The selection of an oxygen plant for the Cyprus Miami smelter modernization project began with a good definition of the use requirements and the smelter process variables that can affect oxygen demand. To achieve a reliable supply of oxygen with a reasonable amount of capital, critical equipment items were reviewed and reliability was added through the use of installed spares, purchase of insurance spare parts or the installation of equipment design for 50 percent of the production design such that the plant could operate with one unit while the other unit is being maintained. The operating range of the plant was selected to cover variability in smelter oxygen demand, and it was recognized that the broader operating range sacrificed about two to three percent in plant power consumption. Careful consideration of the plant "design point" was important to both the capital and operating costs of the plant, and a design point was specified that allowed a broad range of operation for maximum flexibility.

Incubation of air-pollution-control residues from secondary Pb smelter in deciduous and coniferous organic soil horizons: Leachability of lead, cadmium and zinc

Energy Technology Data Exchange (ETDEWEB)

Chrastny, Vladislav, E-mail: vladislavchrastny@seznam.cz [University of South Bohemia, Faculty of Science, Studentska 13, 370 05 Ceske Budejovice (Czech Republic); Czech University of Life Sciences Prague, Faculty of Environmental Sciences, Kamycka 129, 165 21 Prague 6 (Czech Republic); Vanek, Ales [Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Kamycka 129, 165 21 Praha 6 (Czech Republic); Komarek, Michael [Czech University of Life Sciences Prague, Faculty of Environmental Sciences, Kamycka 129, 165 21 Prague 6 (Czech Republic); Farkas, Juraj [Czech Geological Survey, Geologicka 6, 152 00 Praha 5 (Czech Republic); Drabek, Ondrej; Vokurkova, Petra [Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Kamycka 129, 165 21 Praha 6 (Czech Republic); Nemcova, Jana [University of South Bohemia, Faculty of Agriculture, Studentska 13, 370 05 Ceske Budejovice (Czech Republic)

2012-03-30

Highlights: Black-Right-Pointing-Pointer Pb smelter fly ash was incubated in forest soil horizons to assess metal mobility. Black-Right-Pointing-Pointer The metal mobilization depends on pH and the ratio of humic/fulvic acids to SOM. Black-Right-Pointing-Pointer The lowest mobilization of Pb, Zn and Cd took place in horizon H (coniferous forest). Black-Right-Pointing-Pointer A huge amount of Cd was found to have leached in the horizon F (deciduous forest). Black-Right-Pointing-Pointer More vulnerable to metal leaching from APC residues is soil from deciduous forest. - Abstract: The leachability of air-pollution-control (APC) residues from a secondary lead smelter in organic soil horizons (F and H) from a deciduous and a coniferous forest during incubation periods of 0, 3 and 6 months were compared in this work. While the concentration of Pb, Zn and Cd associated with the exchangeable/acid extractable fraction in the horizon F from the coniferous forest was higher compared to the deciduous, significantly lower concentrations in the humified horizon H was found. It is suggested that lower pH and a higher share of fulvic acids fraction (FAs) of solid phase soil organic matter (SOM) in the humified soil horizon H from the coniferous compared to the deciduous forest is responsible for a higher metal association with solid phase SOM and therefore a lower metal leaching in a soil system. From this point of view, the humified soil horizon H from the deciduous forest represents a soil system more vulnerable to Pb, Zn and Cd leaching from APC residues.

Aluminum smelter-derived polycyclic aromatic hydrocarbons and flatfish health in the Kitimat marine ecosystem, British Columbia, Canada.

Science.gov (United States)

Johnson, Lyndal L; Ylitalo, Gina M; Myers, Mark S; Anulacion, Bernadita F; Buzitis, Jon; Collier, Tracy K

2015-04-15

From 2000-2004 a monitoring study was conducted to evaluate the impacts of aluminum smelter-derived polycyclic aromatic hydrocarbons (PAHs) on the health of fish in the marine waters of Kitimat, British Columbia, Canada. These waters are part of the historical fishing grounds of the Haisla First Nation, and since the 1950s the Alcan Primary Metal Company has operated an aluminum smelter at the head of the Kitimat Arm embayment. As a result, adjacent marine and estuarine sediments have been severely contaminated with a mixture of smelter-associated PAHs in the range of 10,000-100,000 ng/g dry wt. These concentrations are above those shown to cause adverse effects in fish exposed to PAHs in urban estuaries, but it was uncertain whether comparable effects would be seen at the Kitimat site due to limited bioavailability of smelter-derived PAHs. Over the 5-year study we conducted biennial collections of adult English sole (Parophrys vetulus) and sediment samples at the corresponding capture sites. Various tissue samples (e.g. liver, kidney, gonad, stomach contents) and bile were taken from each animal to determine levels of exposure and biological effects, and compare the uptake and toxicity of smelter-derived PAHs with urban mixtures of PAHs. Results showed significant intersite differences in concentrations of PAHs. Sole collected at sites nearest the smelter showed increased PAH exposure, as well as significantly higher prevalences of PAH-associated liver disease, compared to sites within Kitimat Arm that were more distant from the smelter. However, measures of PAH exposure (e.g., bile metabolites) were surprisingly high in sole from the reference sites outside of Kitimat Arm, though sediment and dietary PAHs at these sites were low, and fish from the areas showed no biological injury. PAH uptake, exposure, and biological effects in Kitimat English sole were relatively lower when compared to English sole collected from urban sites contaminated with PAH mixtures from

Leaching Behavior of Slags from AN Old Lead Smelter in Chihuahua, Mexico: Metals, Chlorides, Nitrates, Sulfates and Tds Analyses

Science.gov (United States)

Espejel-Garcia, D.; Wenglas-Lara, G.; Villalobos-Aragon, A.; Espejel-Garcia, V. V.

2013-05-01

Waste materials (such as, smelter slags, waste glass, tires, plastics, rubbish, ashes, etc.), have a large potential to substitute natural materials, reducing costs, especially for the construction industry. Smelter slags are resistant and have better compression strength values in comparison to natural aggregates, and generally are far beyond of what the standard ratios need to qualify a material as a good one for construction. But this material has a big problem within it: the existence of toxic elements and compounds in high concentrations, which means that water and soil contamination can be present after water infiltrates through this material; so we perform leaching experiments to characterize and measure the possible contamination under controlled conditions. To perform the slags-leaching experiments, we used an EA-NEN-7375-2004 tank test standard from Netherlands. This test was selected because to our knowledge it is the only one which allows the use of coarse material, as the one utilized in construction. The leaching experiments sampling was performed at different times: 6, 24, 168 and 360 hours, to compare the leachate concentration at the two different pH's values (5 and 8) selected to simulate real conditions. For the leaching experiments, the slags were mixed with natural road base material (gravel-sands from volcanic rocks) at different proportions of 30% and 50%. In order to understand the slags' leaching behavior, other experiments were carried out with the pure material, for both (slags and natural aggregates). After analyses by ICP-OES , the slags from this smelter in Chihuahua contain Pb (0.5 - 4 wt.%), Zn (15-35 wt.%) and As (0.6 wt.%), as well such as: bicarbonates, chlorides, nitrates, sulfates, Mg, K, Na, Ca and TDS. Based on the results of the leaching analyses, via atomic absorption technique, we conclude that Pb and As concentrations are provided by the slags, meanwhile, the bicarbonates, chlorides, Na and Ca are contributed by the road

The heavy metal partition in size-fractions of the fine particles in agricultural soils contaminated by waste water and smelter dust

Energy Technology Data Exchange (ETDEWEB)

Zhang, Haibo, E-mail: hbzhang@yic.ac.cn [Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Luo, Yongming, E-mail: ymluo@yic.ac.cn [Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Makino, Tomoyuki [National Institute for Agro-Environmental Sciences, Tsukuba 3058604 (Japan); Wu, Longhua [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Nanzyo, Masami [Tohoku University, Sendai 9808576 (Japan)

2013-03-15

Highlights: ► A continuous flow ultra-centrifugation method has been developed to obtain fine particles from polluted agricultural soil. ► Pollution source affected the heavy metal fractionation in size-fractions by changing soil particle properties. ► The iron oxides affected the distribution of lead species more than other metals in the smelter dust polluted particles. -- Abstract: The partitioning of pollutant in the size-fractions of fine particles is particularly important to its migration and bioavailability in soil environment. However, the impact of pollution sources on the partitioning was seldom addressed in the previous studies. In this study, the method of continuous flow ultra-centrifugation was developed to separate three size fractions (<1 μm, <0.6 μm and <0.2 μm) of the submicron particles from the soil polluted by wastewater and smelter dust respectively. The mineralogy and physicochemical properties of each size-fraction were characterized by X-ray diffraction, transmission electron microscope etc. Total content of the polluted metals and their chemical speciation were measured. A higher enrichment factor of the metals in the fractions of <1 μm or less were observed in the soil contaminated by wastewater than by smelter dust. The organic substance in the wastewater and calcite from lime application were assumed to play an important role in the metal accumulation in the fine particles of the wastewater polluted soil. While the metal accumulation in the fine particles of the smelter dust polluted soil is mainly associated with Mn oxides. Cadmium speciation in both soils is dominated by dilute acid soluble form and lead speciation in the smelter dust polluted soil is dominated by reducible form in all particles. This implied that the polluted soils might be a high risk to human health and ecosystem due to the high bioaccessblity of the metals as well as the mobility of the fine particles in soil.

The heavy metal partition in size-fractions of the fine particles in agricultural soils contaminated by waste water and smelter dust

International Nuclear Information System (INIS)

Zhang, Haibo; Luo, Yongming; Makino, Tomoyuki; Wu, Longhua; Nanzyo, Masami

2013-01-01

Highlights: ► A continuous flow ultra-centrifugation method has been developed to obtain fine particles from polluted agricultural soil. ► Pollution source affected the heavy metal fractionation in size-fractions by changing soil particle properties. ► The iron oxides affected the distribution of lead species more than other metals in the smelter dust polluted particles. -- Abstract: The partitioning of pollutant in the size-fractions of fine particles is particularly important to its migration and bioavailability in soil environment. However, the impact of pollution sources on the partitioning was seldom addressed in the previous studies. In this study, the method of continuous flow ultra-centrifugation was developed to separate three size fractions (<1 μm, <0.6 μm and <0.2 μm) of the submicron particles from the soil polluted by wastewater and smelter dust respectively. The mineralogy and physicochemical properties of each size-fraction were characterized by X-ray diffraction, transmission electron microscope etc. Total content of the polluted metals and their chemical speciation were measured. A higher enrichment factor of the metals in the fractions of <1 μm or less were observed in the soil contaminated by wastewater than by smelter dust. The organic substance in the wastewater and calcite from lime application were assumed to play an important role in the metal accumulation in the fine particles of the wastewater polluted soil. While the metal accumulation in the fine particles of the smelter dust polluted soil is mainly associated with Mn oxides. Cadmium speciation in both soils is dominated by dilute acid soluble form and lead speciation in the smelter dust polluted soil is dominated by reducible form in all particles. This implied that the polluted soils might be a high risk to human health and ecosystem due to the high bioaccessblity of the metals as well as the mobility of the fine particles in soil

Hydrometallurgical treatment of copper smelter dusts. Desarsenification of leaching solutions

International Nuclear Information System (INIS)

Alguacil, F.J.; Magne, L.; Navarro, P.; Simpson, J.

1996-01-01

Copper smelter dusts contain along with this metal, which is amenable for its recovery, a number of other metals (especially arsenic) which are considered as toxic. Different alternatives have been proposed for the treatment of such metallurgical residues and among them Hydrometallurgy shows good perspectives for its application in this field. In the present work different hydrometallurgical processes proposed for the treatment of copper smelter dusts are described and evaluated together with different alternatives given for the Desarsenification of the leaching solutions. (Author) 36 refs

Speciation of Cr(VI) in environmental samples in the vicinity of the ferrochrome smelter.

Science.gov (United States)

Sedumedi, Hilda N; Mandiwana, Khakhathi L; Ngobeni, Prince; Panichev, Nikolay

2009-12-30

The impact of ferrochrome smelter on the contamination of its environment with toxic hexavalent chromium, Cr(VI), was assessed by analyzing smelter dusts, soil, grass and tree barks. For the separation of Cr(VI) from Cr(III), solid samples were treated with 0.1M Na(2)CO(3) and filtered through hydrophilic PDVF 0.45 microm filter prior to the determination of Cr(VI) by electrothermal atomic absorption spectrometry (ET-AAS). Ferrochrome smelter dust was found to contain significant levels of Cr(VI), viz. 43.5 microg g(-1) (cyclone dust), 2710 microg g(-1) (fine dust), and 7800 microg g(-1) (slimes dust) which exceeded the maximum acceptable risk concentration (20 microg g(-1)). The concentration of Cr(VI) in environmental samples of grass (3.4+/-0.2), soil (7.7+/-0.2), and tree bark (11.8+/-1.2) collected in the vicinity of the chrome smelter were higher as compared with the same kind of samples collected from uncontaminated area. The results of the investigation show that ferrochrome smelter is a source of environmental pollution with contamination factors of Cr(VI) ranging between 10 and 50.

Speciation of Cr(VI) in environmental samples in the vicinity of the ferrochrome smelter

International Nuclear Information System (INIS)

Sedumedi, Hilda N.; Mandiwana, Khakhathi L.; Ngobeni, Prince; Panichev, Nikolay

2009-01-01

The impact of ferrochrome smelter on the contamination of its environment with toxic hexavalent chromium, Cr(VI), was assessed by analyzing smelter dusts, soil, grass and tree barks. For the separation of Cr(VI) from Cr(III), solid samples were treated with 0.1 M Na 2 CO 3 and filtered through hydrophilic PDVF 0.45 μm filter prior to the determination of Cr(VI) by electrothermal atomic absorption spectrometry (ET-AAS). Ferrochrome smelter dust was found to contain significant levels of Cr(VI), viz. 43.5 μg g -1 (cyclone dust), 2710 μg g -1 (fine dust), and 7800 μg g -1 (slimes dust) which exceeded the maximum acceptable risk concentration (20 μg g -1 ). The concentration of Cr(VI) in environmental samples of grass (3.4 ± 0.2), soil (7.7 ± 0.2), and tree bark (11.8 ± 1.2) collected in the vicinity of the chrome smelter were higher as compared with the same kind of samples collected from uncontaminated area. The results of the investigation show that ferrochrome smelter is a source of environmental pollution with contamination factors of Cr(VI) ranging between 10 and 50.

Sulfur dioxide emissions from Peruvian copper smelters detected by the ozone monitoring instrument

NARCIS (Netherlands)

Carn, S.A.; Krueger, A.J.; Krotkov, N.A.; Yang, Kai; Levelt, P.F.

2007-01-01

We report the first daily observations of sulfur dioxide (SO2) emissions from copper smelters by a satellite-borne sensor - the Ozone Monitoring Instrument (OMI) on NASA's EOS/Aura spacecraft. Emissions from two Peruvian smelters (La Oroya and Ilo) were detected in up to 80% of OMI overpasses

Osmium isotopic tracing of atmospheric emissions from an aluminum smelter

Science.gov (United States)

Gogot, Julien; Poirier, André; Boullemant, Amiel

2015-09-01

We present for the first time the use of osmium isotopic composition as a tracer of atmospheric emissions from an aluminum smelter, where alumina (extracted from bauxite) is reduced through electrolysis into metallic aluminum using carbonaceous anodes. These anodes are consumed in the process; they are made of petroleum coke and pitch and have high Re/Os elementary ratio. Due to the relatively large geological age of their source material, their osmium shows a high content of radiogenic 187Os produced from in situ187Re radioactive decay. The radiogenic isotopic composition (187Os/188Os ∼ 2.5) of atmospheric particulate emissions from this smelter is different from that of other typical anthropogenic osmium sources (that come from ultramafic geological contexts with unradiogenic Os isotopes, e.g., 187Os/188Os < 0.2) and also different from average eroding continental crust 187Os/188Os ratios (ca. 1.2). This study demonstrates the capacity of osmium measurements to monitor particulate matter emissions from the Al-producing industry.

Cancer risk among workers of a secondary aluminium smelter.

Science.gov (United States)

Maltseva, A; Serra, C; Kogevinas, M

2016-07-01

Cancer risk in secondary aluminium production is not well described. Workers in this industry are exposed to potentially carcinogenic agents from secondary smelters that reprocess aluminium scrap. To evaluate cancer risk in workers in a secondary aluminium plant in Spain. Retrospective cohort study of male workers employed at an aluminium secondary smelter (1960-92). Exposure histories and vital status through 2011 were obtained through personal interviews and hospital records, respectively. Standardized mortality (SMRs) and incidence ratios (SIRs) were calculated. The study group consisted of 98 workers. We found increased incidence and mortality from bladder cancer [SIR = 2.85, 95% confidence interval (CI) 1.23-5.62; SMR = 5.90, 95% CI 1.58-15.11]. Increased incidence was also observed for prostate cancer and all other cancers but neither were statistically significant. No increased risk was observed for lung cancer. Results of this study suggest that work at secondary aluminium smelters is associated with bladder cancer risk. Identification of occupational carcinogens in this industry is needed. © The Author 2016. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Some effects of smelter pollution northeast of Falconbridge, Ontario

Energy Technology Data Exchange (ETDEWEB)

Gorham, E

1960-01-01

A study along a line northwest from the metal smelter at Falconbridge, Ontario, reveals that strong sulphate accumulation in the surface soil occurs only within about one mile of the chimneys emitting sulphur dioxide pollution while effects upon the soil drainage waters are marked to a distance of nearly two miles, and still clearly evident 10 or more miles away. The number of species present in the flora declines sharply within about four miles of the smelter, but certain species (e.g. Pinus strobus, Vaccinium myrtilloides) disappear at much greater distances. Among the most tolerant species are Acer rubrum, Quercus rubra, Sambucus pubens, and Polygonum cilinode.

Speciation of Cr(VI) in environmental samples in the vicinity of the ferrochrome smelter

Energy Technology Data Exchange (ETDEWEB)

Sedumedi, Hilda N. [Department of Chemistry, Tshwane University of Technology, P.O. Box 56208, Arcadia, 0007, Pretoria (South Africa); Mandiwana, Khakhathi L., E-mail: MandiwanaKL@tut.ac.za [Department of Chemistry, Tshwane University of Technology, P.O. Box 56208, Arcadia, 0007, Pretoria (South Africa); Ngobeni, Prince; Panichev, Nikolay [Department of Chemistry, Tshwane University of Technology, P.O. Box 56208, Arcadia, 0007, Pretoria (South Africa)

2009-12-30

The impact of ferrochrome smelter on the contamination of its environment with toxic hexavalent chromium, Cr(VI), was assessed by analyzing smelter dusts, soil, grass and tree barks. For the separation of Cr(VI) from Cr(III), solid samples were treated with 0.1 M Na{sub 2}CO{sub 3} and filtered through hydrophilic PDVF 0.45 {mu}m filter prior to the determination of Cr(VI) by electrothermal atomic absorption spectrometry (ET-AAS). Ferrochrome smelter dust was found to contain significant levels of Cr(VI), viz. 43.5 {mu}g g{sup -1} (cyclone dust), 2710 {mu}g g{sup -1} (fine dust), and 7800 {mu}g g{sup -1} (slimes dust) which exceeded the maximum acceptable risk concentration (20 {mu}g g{sup -1}). The concentration of Cr(VI) in environmental samples of grass (3.4 {+-} 0.2), soil (7.7 {+-} 0.2), and tree bark (11.8 {+-} 1.2) collected in the vicinity of the chrome smelter were higher as compared with the same kind of samples collected from uncontaminated area. The results of the investigation show that ferrochrome smelter is a source of environmental pollution with contamination factors of Cr(VI) ranging between 10 and 50.

Metal Accumulation, Blood δ-Aminolevulinic Acid Dehydratase Activity and Micronucleated Erythrocytes of Feral pigeons (Columba Livia Living Near Former Lead-Zinc Smelter “ Trepça” – Kosovo

Directory of Open Access Journals (Sweden)

Elezaj I. R.

2013-04-01

Full Text Available The concentration of lead in blood and tibia (Pb, zinc (Zn and cupper (Cu in tibia, blood δ- aminolevulinic acid dehydratase (ALA-D; EC: 4.2.1.24 activity, hematocrit value (Hct and micronuclei frequency (MN of peripheral erythrocytes have been determinated in three different populations of feral pigeons (Columba livia; forma urbana and forma domestica, collected in Mitrovica town (situated close to smelter “Trepça”, down closed in 2000 year and in rural area (Koshare willage . The blood lead level in feral pigeons from Mitrovica (forma urbana was 3 times higher (149.6; 50.5 μg% in comparison with that in feral pigeons from Mitrovica (forma domestica and 27.7 times higher (5.4 μg% in comparison with pigeons from rural area. The Pb concentration of tibia of feral pigeons (froma urbana and forma domestica, from Mitrovica town was significantly higher (P<0.001 in comparison with control. The concentration of Zn in tibia of feral pigeons from Mitrovica town (forma urbana, was significantly higher (P<0.006 in comparison with control. The blood ALA-D activity of feral pigeons from Mitrovica town (forma urbana and froma domestica, was significantly inhibited in comparison with control. The blood ALA-D activity of feral pigeons –forma urbana from Mitrovica town was significantly inhibited (P<0.001 in comparison with the blood ALA-D activity of feral pigeons-forma domestica from Mitrovica town. The erythrocyte MN frequency of feral pigeons from Mitrovica was significantly higher (P <0.001 in comparison with controls. The smelter “Trepça” ten year after closed down pose a threat to the local environment, biota and people’s health.

Socio-demographic characteristics of traditional gold smelters in Makassar, south Sulawesi, Indonesia

Science.gov (United States)

Habo Abbas, Hasriwiani; Sakakibara, Masayuki; Hakim Arma, Lukmanul; Hardi Yanti, Iva

2017-06-01

The traditional gold smelting in Makassar, South Sulawesi, Indonesia, is an informal work with the manufacture of gold jewelry as the core activity. Stages of the gold processing include panning, smelting, and refining with mercury. In the current study, we used a social demography analysis to classify the traditional gold smelter workers in this region. Data (e.g. sex, age, education level, time working, and income) were obtained from a questionnaire survey of 58 smelter workers in the Wajo and Tallo Sub-districts of Makassar. Results showed that 84.5% of the workers were males aged from 21 to 50 years with on the average 15 year of work. The gold smelter were last educated in elementary school (31.0%), junior high school (36.2%), and senior high school (27.6%) levels whereas 5.1% have no education. We found that the monthly income of an un-skilled worker was ∼Rp. 2 million (USD 147.0) whereas that of a skilled worker was between Rp. 2.5 million (USD 183.76) and Rp. 5 million (USD 367.51). An owner could earn over Rp. 5 million (USD 367.51) per month. The result suggested that the traditional gold smelting used rudimentary technique and attracted young people with a low education level. This business continues to exist because the worker earn sufficient income and may higher through mastering gold smelter proficiency.

Diel cycles in dissolved barium, lead, iron, vanadium, and nitrite in a stream draining a former zinc smelter site near Hegeler, Illinois

Science.gov (United States)

Kay, R.T.; Groschen, G.E.; Cygan, G.; Dupre, David H.

2011-01-01

Diel variations in the concentrations of a number of constituents have the potential to substantially affect the appropriate sampling regimen in acidic streams. Samples taken once during the course of the day cannot adequately reflect diel variations in water quality and may result in an inaccurate understanding of biogeochemical processes, ecological conditions, and of the threat posed by the water to human health and the associated wildlife. Surface water and groundwater affected by acid drainage were sampled every 60 to 90. min over a 48-hour period at a former zinc smelter known as the Hegeler Zinc Superfund Site, near Hegeler, Illinois. Diel variations related to water quality in the aquifer were not observed in groundwater. Diel variations were observed in the temperature, pH, and concentration of dissolved oxygen, nitrite, barium, iron, lead, vanadium, and possibly uranium in surface water. Temperature, dissolved oxygen, nitrite, barium, lead, and uranium generally attained maximum values during the afternoon and minimum values during the night. Iron, vanadium, and pH generally attained minimum values during the afternoon and maximum values during the night. Concentrations of dissolved oxygen were affected by the intensity of photosynthetic activity and respiration, which are dependent upon insolation. Nitrite, an intermediary in many nitrogen reactions, may have been formed by the oxidation of ammonium by dissolved oxygen and converted to other nitrogen species as part of the decomposition of organic matter. The timing of the pH cycles was distinctly different from the cycles found in Midwestern alkaline streams and likely was the result of the photoreduction of Fe3+ to Fe 2+ and variations in the intensity of precipitation of hydrous ferric oxide minerals. Diel cycles of iron and vanadium also were primarily the result of variations in the intensity of precipitation of hydrous ferric oxide minerals. The diel variation in the concentrations of lead, uranium

Heavy metals in the atmosphere coming from a copper smelter in Chile

Science.gov (United States)

Romo-Kröger, C. M.; Morales, J. R.; Dinator, M. I.; Llona, F.; Eaton, L. C.

The Chilean mine El Teniente is the world's largest underground copper mine. It operates a giant smelter at Caletones (34° 7' S, 70° 27' W) and we have found it is the major source of air contamination in the region. In August 1991 a special circumstance occurred due to a labor strike, with total cessation of activities. A time series analysis of airborne particles collected at a site about 13 km from the smelter was performed in a period including the strike. The PIXE method and other techniques were used to analyse fine (Elemental characterization of soil samples by radioactive source analysis demonstrated that this group of elements did not come from airborne soil dust. Cluster analyses of the interelement correlation matrices, resulting from PIXE data, showed one group (Si, K, Ca, Fe) with main origin in soil and another group (S, Cu, Zn, As) coming from the copper smelter.

Health and Safety Laboratory environmental quarterly, March 1, 1977--June 1, 1977. [Air pollution in environs of Cu smelter and fallout radionuclides in food chains

Energy Technology Data Exchange (ETDEWEB)

Hardy, E.P. Jr.

1977-07-01

This report presents current information from the HASL environmental programs, The Technical University of Wroclaw, Poland, and the Radiological and Environmental Research Division of Argonne National Laboratory. The initial section consists of interpretive reports and notes on environmental levels of lead and mercury in the area of a copper smelter, radionuclide uptake by cultivated dusts in crops, and fallout strontium-90 in diet through 1976. Subsequent sections include tabulations of radionuclide concentrations in stratospheric air, radionuclide and stable lead concentrations in surface air, strontium-90 in deposition, milk, diet, and tapwater and cesium-137 in diet and tapwater. A bibliography of recent publications related to environmental studies is also presented.

Minimizing lead release levels in secondary smelters slags

International Nuclear Information System (INIS)

Shenkler, E.S.; Graham, S.; Ghosh, R.; Greenhut, V.A.

1991-01-01

Five lead-containing slags and four mattes were analyzed to reveal microstructure, semi-quantitative microchemistry, and phases present. To determine if the slags could be incorporated as a glass so that lead release levels could be stabilized, glass batches were formulated based on slag compositions. Leaching tests showed that all materials that were fritted in a glass batch had lower lead release levels than non-adjusted materials, and all could satisfy EPA test requirements. The mole ratio of glass modifiers to glass formers played an important role in the extent of lead release. Small additions of phosphate to a batch had a significant effect on lowering lead release levels

Effects of zinc smelter emissions on farms and gardens at Palmerton, PA

Science.gov (United States)

Chaney, R.L.; Beyer, W.N.; Gifford, C.H.; Sileo, L.

1988-01-01

In 1979, before the primary Zn smelter at Palmerton was closed due to excessive Zn and Cd emissions and change in the price of Zn, we were contacted by a local veterinarian regarding death of foals (young horses) on farms near the smelter. To examine whether Zn or Cd contamination of forage or soils could be providing potentially toxic levels of Zn or other elements in the diets of foals, we measured metals in forages, soils, and feces of grazing livestock on two farms near Palmerton. The farms were about 2.5 and about 10 km northeast of the East stack. Soils, forages, and feces were greatly increased in Zn and Cd. Soil, forage, and fecal Zn were near 1000 mg/kg and Cd, 10-20 mg/kg at farm A (2.5 km) compared to normal background levels of 43 mg Zn and 0.2 mg Cd/kg, respectively. Liver and kidney of cattle raised on Farm A were increased in Zn and Cd, indicating that at least part of the Zn and Cd in smelter contaminated forages was bioavailable. During the farm sampling, we obtained soil from one garden in Palmerton within 200 m of the primary (West) smelter. The Borough surrounds the smelter facility in a valley. Because soil Cd was near 100 mg/kg, we sampled garden soils and vegetables from over 40 gardens in 6 randomly selected blocks and in rural areas at different distances from the smelter during September, 1980. All homes were contacted on each sampled block. Nearly all homes had some garden, while at least 2 appeared to grow over 50% of their annual vegetable and potato consumption. Palmerton garden soils averaged 76 mg Cd/kg and 5830 mg Zn/kg. Gardeners had been taught to add limestone and organic fertilizers to counteract yield reduction and chlorosis due to the excessive soil Zn. Gardens with over 5000 mg Zn/kg were nearly allover pH 7, and many were calcareous. Because the smelter had not yet ceased operations in 1980, crops could have been polluted by aerosol Zn and Cd emitted by the smelter. Crop Zn and Cd were extremely high, about 100 times normal

The mineralogy of bauxite for producing smelter-grade alumina

Science.gov (United States)

Authier-Martin, M.; Forte, G.; Ostap, S.; See, J.

2001-12-01

Aluminum-producing companies rely on low-cost, high-purity, smelter-grade alumina (aluminum oxide), and alumina production utilizes the bulk of bauxites mined world-wide. The mineralogy of the bauxites has a significant impact on the operation of the Bayer process for alumina production. Typically, the Bayer process produces smelter-grade alumina of 99.5% Al2O3, starting from bauxite containing 30% to 60% Al2O3. The main objective of the Bayer process is to extract the maximum amount of aluminum from the bauxite at as high an aluminate concentration in solution as possible, while limiting any troublesome side reactions. Only with a better understanding of the chemistry of the mineral species and a strict control of the operating/processing conditions can the Bayer process produce efficiently, a low cost, high-quality alumina with minimum detrimental environmental impact.

Mercury contamination in vicinity of secondary copper smelters in Fuyang, Zhejiang Province, China: Levels and contamination in topsoils

International Nuclear Information System (INIS)

Yin Xuebin; Yao Chunxia; Song Jing; Li Zhibo; Zhang Changbo; Qian Wei; Bi De; Li Chenxi; Teng Ying; Wu Longhua; Wan Hongdong; Luo Yongming

2009-01-01

In the present study, we aim to investigate the extent of soil contamination by Hg, particularly by anthropogenic Hg, and tentatively estimate the total Hg (Hg T ) accumulation in topsoils (0-15 cm) in Fuyang, Zhejiang Province-a secondary Cu smelter of China. The results show that the levels of soil Hg in the vicinity of the smelters have been substantially elevated following local smelting activities. The spatial distribution of soil Hg in this area reveals a rapid decrease as the distance from the smelter reaches 1.5 km, which is probably due to the quick deposition process of particulate Hg and reactive gaseous Hg emitted from the smelters. The total accumulation of Hg T in the topsoils of the study area of 10.9 km 2 is approximately 365-561 kg and of which 346-543 kg might be contributed by anthropogenic emission alone with an annual emission of 17.3-27.2 kg Hg to the topsoils. - Secondary copper smelters in Fuyang release a considerable amount of mercury into topsoils.

Incubation of air-pollution-control residues from secondary Pb smelter in deciduous and coniferous organic soil horizons: leachability of lead, cadmium and zinc.

Science.gov (United States)

Chrastný, Vladislav; Vaněk, Aleš; Komárek, Michael; Farkaš, Juraj; Drábek, Ondřej; Vokurková, Petra; Němcová, Jana

2012-03-30

The leachability of air-pollution-control (APC) residues from a secondary lead smelter in organic soil horizons (F and H) from a deciduous and a coniferous forest during incubation periods of 0, 3 and 6 months were compared in this work. While the concentration of Pb, Zn and Cd associated with the exchangeable/acid extractable fraction in the horizon F from the coniferous forest was higher compared to the deciduous, significantly lower concentrations in the humified horizon H was found. It is suggested that lower pH and a higher share of fulvic acids fraction (FAs) of solid phase soil organic matter (SOM) in the humified soil horizon H from the coniferous compared to the deciduous forest is responsible for a higher metal association with solid phase SOM and therefore a lower metal leaching in a soil system. From this point of view, the humified soil horizon H from the deciduous forest represents a soil system more vulnerable to Pb, Zn and Cd leaching from APC residues. Copyright © 2012 Elsevier B.V. All rights reserved.

A Heavy Metal Atmospheric Deposition Study Around the Lead and Copper-Zinc Smelters in Baia Mare, Romania, Employing the Moss Biomonitoring Technique, ENAA and FAAS

CERN Document Server

Culicov, O A; Steinnes, E; Okina, O S; Santa, Z; Todoran, R

2001-01-01

The mosses Pleurozium schreberi, Pseudoscleropodium purum and Rhytidiadelphus squarrosus were used as biomonitors to study the atmospheric deposition of metals around the lead and copper-zinc smelters in Baia Mare. Samples representing the last three years' growth of moss or its green part, collected on the ground at 28 sites located 2-20 km from the source area, were analyzed by instrumental neutron activation analysis using epithermal neutrons (ENAA) and by flame atomic absorption spectrometry (FAAS). A total of 30 elements were determined, including most of the heavy metals known to be released into the air from this kind of industry. Obtained concentrations for As and Cu are comparable with those observed in Karabash, South Ural Mountains, one of the most polluted regions in Europe. Besides, these two elements correlate very well with each other. The mean values for Zn (136 ppm) and Pb (41 ppm) are substantially higher than those normally found in the literature. The highest value for Pb (175 ppm) was obs...

Contrasting isotopic signatures between anthropogenic and geogenic Zn and evidence for post-depositional fractionation processes in smelter-impacted soils from Northern France

Science.gov (United States)

Juillot, Farid; Maréchal, Chloe; Morin, Guillaume; Jouvin, Delphine; Cacaly, Sylvain; Telouk, Philipe; Benedetti, Marc F.; Ildefonse, Philippe; Sutton, Steve; Guyot, François; Brown, Gordon E., Jr.

2011-05-01

Zinc isotopes have been studied along two smelter-impacted soil profiles sampled near one of the largest Pb and Zn processing plants in Europe located in northern France, about 50 km south of Lille. Mean δ 66Zn values along these two soil profiles range from +0.22 ± 0.17‰ (2 σ) to +0.34 ± 0.17‰ (2 σ) at the lowest horizons and from +0.38 ± 0.45‰ (2 σ) to +0.76 ± 0.14‰ (2 σ) near the surface. The δ 66Zn values in the lowest horizons of the soils are interpreted as being representative of the local geochemical background (mean value +0.31 ± 0.38‰), whereas heavier δ 66Zn values near the surface of the two soils are related to anthropogenic Zn. This anthropogenic Zn occurs in the form of franklinite (ZnFe 2O 4)-bearing slag grains originating from processing wastes at the smelter site and exhibiting δ 66Zn values of +0.81 ± 0.20‰ (2 σ). The presence of franklinite is indicated by EXAFS analysis of the topsoil samples from both soil profiles as well as by micro-XANES analysis of the surface horizon of a third smelter-impacted soil from a distant site. These results indicate that naturally occurring Zn and smelter-derived Zn exhibit significantly different δ 66Zn values, which suggests that zinc isotopes can be used to distinguish between geogenic and anthropogenic sources of Zn in smelter-impacted soils. In addition to a possible influence of additional past sources of light Zn (likely Zn-sulfides and Zn-sulfates directly emitted by the smelter), the light δ 66Zn values in the surface horizons compared to smelter-derived slag materials are interpreted as resulting mainly from fractionation processes associated with biotic and/or abiotic pedological processes (Zn-bearing mineral precipitation, Zn complexation by organic matter, and plant uptake of Zn). This conclusion emphasizes the need for additional Zn isotopic studies before being able to use Zn isotopes to trace sources and pathways of this element in surface environments.

Influence of smelter fumes on the growth of white pine in the Sudbury region

Energy Technology Data Exchange (ETDEWEB)

Linzon, S N

1958-01-01

An additional study was started in 1949 to determine the effects on neighboring white pine forests of sulfur fumes discharged from large smelters operated by two mining companies in the Sudbury district of Ontario. A number of sample timber areas, near to, farther removed, and remote from the sources of the fumes, were placed under observation. Approximately 7000 white pine trees in the vigorous age class of 50 to 90 years had been examined annually by 1954. Foliage on the white pine trees located less than 25 miles northeast of Sudbury showed more extensive injuries every year than foliage on trees located at greater distances from the smelters. Studies of diameter increment showed that there was a gradual decline in the annual growth of white pine in the areas near to the smelters, whereas a constant pattern was maintained in areas located farther from the sources of smoke. Further, in the areas close to the smelters, the volume of white pine lost through excessive tree mortality of all crown class sizes exceeded the volume added by the surviving trees. However, at distances beyond 25 to 30 miles northeast of Sudbury in the direction of the prevailing wind the condition of white pine improved remarkably. It is indicated that the combination of concentration frequency, and duration of atmospheric sulfur dioxide visitations has here declined to a threshold value for the inhibition of growth of white pine. 25 references, 25 figures, 23 tables.

Patterns of insect communities along a stress gradient following decommissioning of a Cu-Ni smelter

International Nuclear Information System (INIS)

Babin-Fenske, Jennifer; Anand, Madhur

2011-01-01

The diversity, estimated richness and abundance of terrestrial insect communities were examined along a stress gradient of past pollution in the region of Sudbury, Ontario, Canada. This gradient represents the natural recovery and lingering effects of a decommissioned copper-nickel smelting complex. Ant genera and sixteen higher taxonomic groups (family and order) had the highest abundance at the sites with intermediate stress. Eight families increased in abundance with distance from the decommissioned source of pollution and eleven families decreased reflecting a complex response of diversity to pollution. Carabid beetles show an increase in diversity further from the smelter; however, examination of the species composition reveals a distinct carabid community closest to the smelter, emphasizing the unique habitat created by severe pollution. Although almost forty years since decomissioning of the smelter complex, the terrestrial insect community in the vicinity remains significantly impacted suggesting slow recovery. - Highlights: → Several taxonomic groups had highest abundance at intermediate stress. → Eight families increased in abundance with distance from the source of pollution. → Eleven families decreased in abundance with distance. → Species composition reveals a distinct carabid community closest to the smelter. → Terrestrial insect community still significantly impacted suggesting slow recovery. - Our study finds both unexpected and expected responses of insect communities to a landscape gradient of past pollution suggesting the emergence of novel ecosystems.

Metal pollution around an iron smelter complex in northern Norway at different modes of operation

International Nuclear Information System (INIS)

Steinnes, E.; Sjoebakk, T.E.; Frontas'eva, M.V.; Varskog, P.

2003-01-01

The moss biomonitoring technique was employed to study the atmospheric deposition in and around the town of Mo i Rana, northern Norway, before and after closing an iron smelter and establishing alternative ferrous metal industries. Samples of Hylocomium splendens were collected from the same sites in 1989 and 1993. A combination of instrumental neutron activation analysis (INAA) and atomic absorption spectrometry was used to obtain data for 38 elements in these moss samples, and the analytical data were subjected to factor analysis. In general, the deposition was higher when the iron smelter was still in operation, in particular for Fe and for many elements normally associated with crustal matter. For Cr there was a substantially increased deposition due to the operation of a new ferrochrome smelter. Also for Ni and Au an increased deposition was observed, whereas for metals such as Mn, Co, Ag, Sb, and W there was no appreciable change. INAA proved to be a powerful tool for this kind of study. The regional distribution of pollutants was strongly dependent on the local topography. Samples of natural surface soils collected simultaneously with the first moss series showed clear signs of contamination with a number of metals from atmospheric deposition. The approach described in this work could be advantageously used to study atmospheric deposition of heavy metals around iron smelters in Russia and elsewhere

Patterns of insect communities along a stress gradient following decommissioning of a Cu-Ni smelter

Energy Technology Data Exchange (ETDEWEB)

Babin-Fenske, Jennifer [Department of Biology, Laurentian University, Sudbury, Ontario, P3E 2C6 (Canada); Anand, Madhur, E-mail: manand@uoguelph.ca [School of Environmental Sciences, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada)

2011-10-15

The diversity, estimated richness and abundance of terrestrial insect communities were examined along a stress gradient of past pollution in the region of Sudbury, Ontario, Canada. This gradient represents the natural recovery and lingering effects of a decommissioned copper-nickel smelting complex. Ant genera and sixteen higher taxonomic groups (family and order) had the highest abundance at the sites with intermediate stress. Eight families increased in abundance with distance from the decommissioned source of pollution and eleven families decreased reflecting a complex response of diversity to pollution. Carabid beetles show an increase in diversity further from the smelter; however, examination of the species composition reveals a distinct carabid community closest to the smelter, emphasizing the unique habitat created by severe pollution. Although almost forty years since decomissioning of the smelter complex, the terrestrial insect community in the vicinity remains significantly impacted suggesting slow recovery. - Highlights: > Several taxonomic groups had highest abundance at intermediate stress. > Eight families increased in abundance with distance from the source of pollution. > Eleven families decreased in abundance with distance. > Species composition reveals a distinct carabid community closest to the smelter. > Terrestrial insect community still significantly impacted suggesting slow recovery. - Our study finds both unexpected and expected responses of insect communities to a landscape gradient of past pollution suggesting the emergence of novel ecosystems.

Metal Pollution Around an Iron Smelter Complex in Northern Norway at Different Modes of Operation

CERN Document Server

Steinnes, E; Eidhammer-Sjobakk, T; Varskog, P

2003-01-01

The moss biomonitoring technique was employed to study the atmospheric deposition in and around the town of Mo i Rana, northern Norway, before and after closing an iron smelter and establishing alternative ferrous metal industries. Samples of Hylocomium splendens were collected from the same sites in 1989 and 1993. A combination of instrumental neutron activation analysis (INAA) and atomic absorption spectrometry was used to obtain data for 38 elements in these moss samples, and the analytical data were subjected to factor analysis. In general, the deposition was higher when the iron smelter was still in operation, in particular for Fe and for many elements normally associated with crustal matter. For Cr there was a substantially increased deposition due to the operation of a new ferrochrome smelter. Also for Ni and Au an increased deposition was observed, whereas for metals such as Mn, Co, Ag, Sb, and W there was no appreciable change. INAA proved to be a powerful tool for this kind of study. The regional di...

The impact of a copper smelter on adjacent soil zinc and cadmium fractions and soil organic carbon

Energy Technology Data Exchange (ETDEWEB)

Liu Ling; Wu Longhua; Luo Yongming [Key Lab. of Soil Environment and Pollution Remediation, Chinese Academy of Sciences, NJ (China); Zhang Changbo [Shanghai Academy of Environmental Sciences, SH (China); Jiang Yugen; Qiu Xiya [Soils and Fertilisers Div., Fuyang City Agricultural Bureau, Hangzhou, ZJ (China)

2010-07-15

Purpose: We investigated the chemical fractions of Zn, Cd and Cu in soils collected from positions at different distances from a copper smelter and studied the relationships between distribution patterns of Zn, Cd and Cu, fractions and soil organic carbon (SOC), especially ''black carbon'' (BC), in contaminated soils. The relationships between soil particle size and concentrations of Zn and Cd in contaminated soil were also examined. Materials and methods: Soil samples were collected from field sites at different distances from the copper smelter, air-dried and passed through 0.25-mm and 0.149-mm nylon mesh sieves. The SOC and BC were determined. Aqua regia and sequentially extracted Zn, Cd and Cu fractions in soil and the different sizes of soil particles, and metal concentrations (Zn, Cd and Cu) in BC were also determined. Results and discussion: The soils were heavily contaminated by fly ash from the copper smelter. Concentrations of Zn, Cd and Cu in soil and SOC decreased with increasing distance from the smelter. Concentrations of Zn and Cd in the surface soil (0-15 cm) decreased from 27,017 to 892 mg kg{sup -1} and from 18.7 to 1.04 mg kg{sup -1}, respectively. Soil BC and concentrations of Zn, Cd and Cu in the BC fraction showed significant and positive relationships with the corresponding aqua regia metal concentrations in soil. Soil Zn and Cd occurred predominantly in the exchangeable and reducible fractions, but residual and oxidisable fractions of Cu that were not considered mobile or bioavailable were predominant (>60%). Concentrations of Zn and Cd in the soil particle size fractions tended to increase with decreasing particle size. Conclusions: The Cd and Zn and BC were all derived from the fly ash of the smelter. Concentrations of Zn and Cd and BC in the soil decreased significantly with increasing distance from the smelter. Zinc and Cd in contaminated soils increased as particle size decreased, and were mainly in highly available

The structure of spruce-fir tree stands mortality under impact of the Middle Ural copper smelter emissions

Directory of Open Access Journals (Sweden)

I. E. Bergman

2015-04-01

Full Text Available The influence of industrial pollution on mortality values (dead fallen wood and dead standing trees and its distribution by degrees of decomposition were investigated in spruce-fir forest stands in the vicinity of the Middle Ural copper smelter (the city of Revda, Sverdlovsk region. The total mortality and mortality in each size category did not depend on the distance to the source of pollution. At the same time, the amount of dead fallen wood was significantly greater (1.9 times in the polluted area (2 and 4 km from the smelter as compared with the background territory (30 km from the smelter. Mortality proportion out of the total number of the trees (both live and dead did not differ significantly between the sites, although this parameter tended to increase nearer the smelter. The distribution of mortality by size categories revealed significant differences between background territory and site with average level of contamination, as well as background territory and highly contaminated site. Observed differences are associated with an increased proportion of lesser mortality near the smelter (by 15 % and 12 % as compared with areas of background and middle levels of contamination, respectively, as well as because of double-declining of medium- and large-sized mortality near the smelter. The distribution of the living tree stands by size categories also has a connection with level of contamination. The average diameters of the living tree stand and the elements of coarse woody debris (dead fallen wood and dead standing trees do not differ significantly between sites with different levels of contamination. For the small-sized dead fallen wood, the proportion of weakly decomposed stems increased with the level of pollution, while proportion of strongly decomposed stems decreased. The distribution of medium- and large-sized dead fallen wood on the stages of decomposition does not vary between sites with different levels of pollution.

Lead Effect on Aminolevulinic Acid Dehydratase Activity of Feral Pigeon (Columba livia in Drenas

Directory of Open Access Journals (Sweden)

Albana Plakiqi Milaimi

2015-09-01

Full Text Available This study was aimed to investigate the effects of environmental pollution with heavy metals from ferro-nickel smelter on Aminolevulinic Acid Dehydratase (ALAD activity, and to analyze the blood lead level of feral pigeon (Columba livia in ferro-nickel smelter courtyard in Drenas City, Republic of Kosovo. For this purpose, twenty specimens of feral pigeon (20 birds, males and females, were collected in Drenas city which were living in ferro-nickel smelter courtyard, and 20 specimens in Lubizhdë village as control group (non-contaminated area. ALAD activity in Drenas group was significantly inhibited (P<0.001, compared with ALAD activity of controls. The blood lead level was significantly increased (P=0.015 compared to control group. Correlation between ALAD and blood lead level in Drenas group was negative (r=-0.117; P>0.050 and positive in Lubizhdë group (r=0.452; P> 0.050, but not in significant difference between the input groups. Feral pigeons can play an important role as bioindicators, which can used to monitor the environmental pollution with heavy metals that may originate from Nickel metallurgy.

Integration of the predictions of two models with dose measurements in a case study of children exposed to the emissions of a lead smelter

Energy Technology Data Exchange (ETDEWEB)

Bonnard, R.; McKone, T.E.

2009-03-01

The predictions of two source-to-dose models are systematically evaluated with observed data collected in a village polluted by a currently operating secondary lead smelter. Both models were built up from several sub-models linked together and run using Monte-Carlo simulation, to calculate the distribution children's blood lead levels attributable to the emissions from the facility. The first model system is composed of the CalTOX model linked to a recoded version of the IEUBK model. This system provides the distribution of the media-specific lead concentrations (air, soil, fruit, vegetables and blood) in the whole area investigated. The second model consists of a statistical model to estimate the lead deposition on the ground, a modified version of the model HHRAP and the same recoded version of the IEUBK model. This system provides an estimate of the concentration of exposure of specific individuals living in the study area. The predictions of the first model system were improved in terms of accuracy and precision by performing a sensitivity analysis and using field data to correct the default value provided for the leaf wet density. However, in this case study, the first model system tends to overestimate the exposure due to exposed vegetables. The second model was tested for nine children with contrasting exposure conditions. It managed to capture the blood levels for eight of them. In the last case, the exposure of the child by pathways not considered in the model may explain the failure of the model. The interest of this integrated model is to provide outputs with lower variance than the first model system, but at the moment further tests are necessary to conclude about its accuracy.

Impact of mercury mine and smelter St. Ana – Podljubelj on spatial distribution of chemical elements in soil

Directory of Open Access Journals (Sweden)

Tamara Teršič

2005-06-01

Full Text Available The objective of the research project was to establish the extension of Hg pollution as a consequence of mining and smelting activities in a narrow Alpine valley. The St. Ana mine was first exploited as early as in 1557 and was finally abandoned in 1902. The entire operating period yielded about 110.000 tons of ore, from which 360 tons of Hg was produced. By soil sampling it was established that on about 9 ha the Hg contents in soil exceed the Slovenian critical values for soil (10 mg/kg. The estimated mercury mean for the studied area is 1.3 mg/kg (0.17 – 718 mg/kg. The highest contents of mercury in soilswere found in the area of the mercury smelter.That is a consequence of former atmospheric emissions and technological losses. High values of Hg were found also in soil on the mine and smelter waste dump. The highest determined contents of Hg (108 mg/kg in this area are almost 7-times lower than thecontents of Hg in the area of the smelter. Mercury in soils generally decrease with depth and distance from the mine and smelter. Apart from the area around the former mine and smelter, mercury appear in higher concentrations also along the road that runs along thevalley, which is due to the use of Hg bearing mine tailings in road construction.

Reductive-sulfurizing smelting treatment of smelter slag for copper and cobalt recovery

Directory of Open Access Journals (Sweden)

Li Y.

2018-01-01

Full Text Available Recovery of copper and cobalt from smelter slag using reductive-sulfurizing smelting method was performed in this study. The effects of reductive agent (coke, sulfurizing agent (pyrite, slag modifier (CaO and smelting temperature and duration on the extractive efficiencies of Cu, Co and Fe were discussed. The phase compositions and microstructure of the materials, copper-cobalt matte and cleaned slag were determined. The results showed that copper and cobalt contents in cleaned slag could decrease averagely to 0.18% and 0.071% respectively after cleaning. 91.99% Cu and 92.94% Co and less than 38.73% Fe were recovered from the smelter slag under the optimum conditions: 6 wt.% coke, 20 wt.% pyrite and 6 wt.% CaO addition to the smelter slag, smelting temperature of 1350°C and smelting duration of 3h. The addition of CaO can increase the selectivity of Co recovery. The cleaning products were characterized by XRD and SEM-EDS analysis. The results showed that the main phases of copper-cobalt matte were iron sulfide (FeS, geerite (Cu8S5, iron cobalt sulfide (Fe0.92Co0.08S and Fe-Cu-Co alloy. The cleaned slag mainly comprised fayalite (Fe2SiO4, hedenbergite (CaFe(Si2O6 and magnetite (Fe3O4.

The Feasibility of Using Lead in Hair Concentration in Monitoring Environmental Exposure in Children

NARCIS (Netherlands)

Wibowo, A.A.E.; Brunekreef, B.; Lebret, E.; Pieters, H.

1980-01-01

The feasibility of lead in hair as an indicator of lead exposure has been compared to that of lead in blood and zinc protoporphyrin in blood levels in 1-3 year-old children living within 1 km of a lead smelter. Lead exposure was measured as lead in house dust, outdoor and indoor lead in air

Treatment of metallurgical wastes : recovery of metal values from smelter slags by pressure oxidative leaching

Energy Technology Data Exchange (ETDEWEB)

Li, Y.; Perederiy, I.; Papangelakis, V.G. [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry

2008-07-01

Vast quantities of slag are produced and dumped as waste by-products during the production of base metals by smelting operations. These slags contain large amounts of valuable metals which lead to a decrease in metal yield and, combined with the entrapped sulphur, pose a danger to the environment. The dissolution of fayalite is important for the selective recovery of valuable metals and the cleanup of slags in high pressure oxidative leaching. The nature of base metals and iron in solidified slag must be investigated in order to understand the mechanism of the process. This paper discussed the application of powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) for the characterization of a smelter slag microstructure. The study used leaching tests with the same smelter slag to measure and monitor the results of leaching, including metal extraction levels, the extent of iron dissolution as well as impurity contents. The paper provided information on the experiment with particular reference to slag leaching, chemical analysis, and characterization. It was concluded that slag consists of several solid phases with base metal sulfide and oxide droplets entrapped in the fayalite matrix or silica regions. Therefore, nickel, copper, cobalt, and zinc need to be exposed either chemically or mechanically to promote their recovery. 21 refs., 4 tabs., 5 figs.

Assessment of a remediation technique using the replacement of contaminated soils in kitchen gardens nearby a former lead smelter in Northern France.

Science.gov (United States)

Douay, F; Roussel, H; Pruvot, C; Loriette, A; Fourrier, H

2008-08-15

Vegetables cultivated in kitchen gardens that are strongly contaminated by heavy metals (Pb, Cd) may represent to consumers a means of exposure to these metals. This exposure is more problematic for those families that include a large quantity of home-grown vegetables in their diet. Researchers have shown that the majority of vegetables produced in kitchen gardens in the vicinity of the Metaleurop Nord smelter (Northern France) do not conform to European regulations. This study was carried out in three of these kitchen gardens. The concentrations of Cd and Pb in the topsoils were up to 24 and 3300 mg kg(-1) respectively. The method consisted of delineating a surface area of about 50 to 100 m(2) for each garden, then removing the contaminated soil and replacing it with a clean one. Seven species of vegetables were cultivated from 2003 to 2005 in the original contaminated soils and the remediated ones. The data showed a clear improvement of the quality of the vegetables cultivated in remediated soils, although 17% of them were still over the European legislative limits for foodstuffs. This suggested that there was a foliar contamination due to contaminated dust fallout coming from the closed smelter site and the adjacent polluted soils. In addition, the measurement of the Cd and Pb concentrations in the dust fallout showed that the substantial rise in metal concentrations in the remediated soil was not only due to atmospheric fallout. These results raise questions about possible technical, economic and sociological problems associated with this kind of remediation.

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....

Preliminary studies of airborne particulate emmisions from the Ampellum S.A. copper smelter, Zlatna, Romania

Directory of Open Access Journals (Sweden)

Ben J. Williamson

2003-04-01

Full Text Available Preliminary studies have been carried on the characterization of particulate emissions from the Ampellum S.A. copper smelter in the town of Zlatna, Romania. The particulates studied were collected on polycarbonate filters using air pump apparatus and on the surfaces of lichens. Mass of total suspended particulates (TSP and PM10 varied from 19 to 230 μg/m3 and 3 to 146 μg/m3, respectively (PM10/TSP = 0.14 to 1.0, depending on wind direction and proximity to the smelter. Particulates on collection filters from a site directly downwind from the smelter have a mean equivalent spherical diameter (ESD of 0.94 μm (s.d. 1.1 and are dominantly made up of material with the composition of anglesite (PbSO4. The remainder of the material is a heterogeneous mixture of silicates and Fe-, Pb- and Cu-bearing phases. Particulates > 5 μm ESD are rare on the TSP filters, mainly due to the restricted sampling durations possible with the equipment used (<3 hours. Particulates have therefore been studied in the lichen Acarospora smaragdula, which was growing on posts downwind from the smelter and which was found to contain high levels and a broader range of particulates compared with the filters (<5 to 100 μm in diameter. Larger particles include 20-30 μm diameter Fe-rich spherules, which occasionally have Pb- and S-rich encrustations on their surfaces. The nature and possible health effects of the particulates are discussed and recommendations made for future studies.

Visualisation and quantification of heavy metal accessibility in smelter slags: The influence of morphology on availability

International Nuclear Information System (INIS)

Morrison, Anthony L.; Swierczek, Zofia; Gulson, Brian L.

2016-01-01

The Imperial Smelting Furnace (ISF) for producing lead and zinc simultaneously has operated on four continents and in eleven countries from the 1950's. One of the process changes that the ISF introduced was the production of a finely granulated slag waste. Although this slag contained significant amounts of residual lead (Pb) and zinc (Zn), because of its glassy nature it was considered environmentally benign. From the Cockle Creek smelter near Boolaroo at the northern end of Lake Macquarie, NSW, Australia, it is estimated that around 2.1 million tonnes of the fine slag was distributed into the community and most remains where it was originally utilised. Residual tonnages of slag of this magnitude are common worldwide wherever the ISF operated. Studies of base metal smelting slags have concluded that mineralogical and morphological characteristics of the slag play a critical role in moderating environmental release of toxic elements. Scanning electron microscopy (SEM) and microanalysis of the ISF slags has shown that the Pb and associated elements are present as discrete nodules (∼6–22 μm) in the slag and that they are not associated with Zn which is contained in the glass slag phase. Using an automated SEM and analysis technique (QEMSCAN"®) to “map” the mineralogical structure of the particles, it was possible to quantitatively determine the degree of access infiltrating fluids might have to the reaction surface of the Pb phases. The level of access decreases with increasing particle size, but in even the largest sized particles (−3350 + 2000 μm) nearly 80% of the Pb-containing phases were totally or partially accessible. These results provide evidence that the toxic elements in the slags are not contained by the glassy phase and will be vulnerable to leaching over time depending on their individual phase reactivity. - Highlights: • QEMSCAN"® allowed determination of access to infiltrating fluids to Pb in smelter slags. • Pb and associated

Comparative Hepatotoxicity Test of Cadmium and Lead in Rats ...

African Journals Online (AJOL)

Background: Adverse environmental impacts include contamination of water, soil, and phytotoxicity from excessive heavy metals dispersed from mines and smelter sites leading to potential risk to human health. This study investigated the comparative hepatotoxicity test of mining pond waters used for domestic purposes in ...

Ammonia leaching of copper smelter dust and precipitation as copper sulphide; Lixiviacion amoniacal de polvos de fundicion de cobre y precipitacion como sulfuro de cobre

Energy Technology Data Exchange (ETDEWEB)

Morales, A.; Hevia, J. F.; Cifuentes, G.

2009-07-01

The effect of ammonia on the leaching of copper smelter dust and copper precipitation from these solutions as sulphide using sulfur and sulfur dioxide was studied. The precipitation was done in ammoniacal media because this solution produced more satisfactory results at room temperature that a sulphuric media. A solid was precipitated containing 60 % of copper of the dust smelter. The other waste generated contained around 80 % of the arsenic of the original copper smelter dust. Based on the preliminary results obtained in this work it will propose a procedure for the recovery of copper as sulphide from copper smelter dust with parallel confinement of arsenic. (Author) 14 refs.

New insight into atmospheric mercury emissions from zinc smelters using mass flow analysis.

Science.gov (United States)

Wu, Qingru; Wang, Shuxiao; Hui, Mulin; Wang, Fengyang; Zhang, Lei; Duan, Lei; Luo, Yao

2015-03-17

The mercury (Hg) flow paths from three zinc (Zn) smelters indicated that a large quantity of Hg, approximately 38.0-57.0% of the total Hg input, was stored as acid slag in the landfill sites. Approximately 15.0-27.1% of the Hg input was emitted into water or stored as open-dumped slags, and 3.3-14.5% of the Hg input ended in sulfuric acid. Atmospheric Hg emissions, accounting for 1.4-9.6% of the total Hg input, were from both the Zn production and waste disposal processes. Atmospheric Hg emissions from the waste disposal processes accounted for 40.6, 89.6, and 94.6% of the total atmospheric Hg emissions of the three studied smelters, respectively. The Zn production process mainly contributed to oxidized Hg (Hg2+) emissions, whereas the waste disposal process generated mostly elemental Hg (Hg0) emissions. When the emissions from these two processes are considered together, the emission proportion of the Hg2+ mass was 51, 46, and 29% in smelters A, B, and C, respectively. These results indicated that approximately 10.8±5.8 t of atmospheric Hg emissions from the waste disposal process were ignored in recent inventories. Therefore, the total atmospheric Hg emissions from the Zn industry of China should be approximately 50 t.

Influences of smelter fumes upon the chemical composition of lake waters near Sudbury, Ontario, and upon the surrounding vegetation

Energy Technology Data Exchange (ETDEWEB)

Gorham, E; Gordon, A G

1960-01-01

Analyses for sulphate, calcium, and pH have been made on surface waters from 102 lakes and ponds in the Sudbury metal-smelting district, and data are presented for 35 of these. Sulphur pollution is frequently high within about 5 miles of the three smelters, many ponds exhibiting more than three times the sulphate concentration normal for this area, and three waters more than 10 times this level. Outside about 15 miles distance the influence of smelter pollution upon sulphate concentrations in surface waters is negligible. As expected, many of the most polluted waters are strongly acid, with pH values going as low as 3.3. Sulphuric acid from air pollution has also led to increased weathering of calcium from soils and rocks, so that this ion tends to rise in concentration not only in waters above pH 6 (as expected) but also in those below pH 5. Damage to terrestrial vegetation is frequently marked within about 5 miles of the smelters, while it is seldom obvious to the untrained eye beyond this distance. Severe damage occurs chiefly within about 2 miles of the smelters.

Spatial distribution and risk assessment of heavy metals in soil near a Pb/Zn smelter in Feng County, China.

Science.gov (United States)

Shen, Feng; Liao, Renmei; Ali, Amjad; Mahar, Amanullah; Guo, Di; Li, Ronghua; Xining, Sun; Awasthi, Mukesh Kumar; Wang, Quan; Zhang, Zengqiang

2017-05-01

A large scale survey and a small scale continuous monitoring was conducted to evaluate the impact of Pb/Zn smelting on soil heavy metals (HMs) accumulation and potential ecological risk in Feng County, Shaanxi province of China. Soil parameters including pH, texture, CEC, spatial and temporal distribution of HMs (Cd, Cu, Ni, Pb and Zn), and BCR fractionation were monitored accordingly. The results showed the topsoil in the proximity of smelter, especially the smelter area and county seat, were highly polluted by HMs in contrast to the river basins. Fractionation of Cd and Zn in soil samples revealed higher proportion of mobile fractions than other HMs. The soil Cd and Zn contents decreased vertically, but still exceeded the second level limits of Environmental Quality Standard for Soils of China (EQSS) within 80cm. The dominated soil pollutant (Cd) had higher ecological risk than Cu, Ni, Zn and Pb. The potential ecological risk (PER) factor of Cd were 65.7% and 100% in surrounding county and smelter area, respectively. The long-term smelter dust emission mainly contributed to the HMs pollution and posed serious environment risk to living beings. Copyright © 2017 Elsevier Inc. All rights reserved.

Ultra-Wideband Tracking System Design for Relative Navigation

Science.gov (United States)

Ni, Jianjun David; Arndt, Dickey; Bgo, Phong; Dekome, Kent; Dusl, John

2011-01-01

This presentation briefly discusses a design effort for a prototype ultra-wideband (UWB) time-difference-of-arrival (TDOA) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being designed for use in localization and navigation of a rover in a GPS deprived environment for surface missions. In one application enabled by the UWB tracking, a robotic vehicle carrying equipments can autonomously follow a crewed rover from work site to work site such that resources can be carried from one landing mission to the next thereby saving up-mass. The UWB Systems Group at JSC has developed a UWB TDOA High Resolution Proximity Tracking System which can achieve sub-inch tracking accuracy of a target within the radius of the tracking baseline [1]. By extending the tracking capability beyond the radius of the tracking baseline, a tracking system is being designed to enable relative navigation between two vehicles for surface missions. A prototype UWB TDOA tracking system has been designed, implemented, tested, and proven feasible for relative navigation of robotic vehicles. Future work includes testing the system with the application code to increase the tracking update rate and evaluating the linear tracking baseline to improve the flexibility of antenna mounting on the following vehicle.

Transformation of arsenic-rich copper smelter flue dust in contrasting soils: A 2-year field experiment.

Science.gov (United States)

Jarošíková, Alice; Ettler, Vojtěch; Mihaljevič, Martin; Penížek, Vít; Matoušek, Tomáš; Culka, Adam; Drahota, Petr

2018-06-01

Dust emissions from copper smelters processing arsenic-bearing ores represent a risk to soil environments due to the high levels of As and other inorganic contaminants. Using an in situ experiment in four different forest and grassland soils (pH 3.2-8.0) we studied the transformation of As-rich (>50 wt% As) copper smelter dust over 24 months. Double polyamide bags with 1 g of flue dust were buried at different depths in soil pits and in 6-month intervals; then those bags, surrounding soil columns, and soil pore waters were collected and analysed. Dust dissolution was relatively fast during the first 6 months (5-34%), and mass losses attained 52% after 24 months. The key driving forces affecting dust dissolution were not only pH, but also the water percolation/retention in individual soils. Primary arsenolite (As 2 O 3 ) dissolution was responsible for high As release from the dust (to 72%) and substantial increase of As in the soil (to a 56 × increase; to 1500 mg kg -1 ). Despite high arsenolite solubility, this phase persisted in the dust after 2 years of exposure. Mineralogical investigation indicated that mimetite [Pb 5 (AsO 4 ) 3 (Cl,OH)], unidentified complex Ca-Pb-Fe-Zn arsenates, and Fe oxyhydroxides partly controlled the mobility of As and other metal(loid)s. Compared to As, other less abundant contaminants (Bi, Cu, Pb, Sb, Zn) were released into the soil to a lesser extent (8-40% of total). The relatively high mobility of As in the soil can be seen from decreases of bulk As concentrations after spring snowmelt, high water-extractable fractions with up to ∼50% of As(III) in extracts, and high As concentrations in soil pore waters. Results indicate that efficient controls of emissions from copper smelters and flue dust disposal sites are needed to prevent extensive contamination of nearby soils by persistent As. Copyright © 2018 Elsevier Ltd. All rights reserved.

Arsenic accumulation in people working with and living near a gold smelter

International Nuclear Information System (INIS)

Jervis, R.E.; Tiefenbach, B.; Toronto Univ., Ontario

1979-01-01

The processing of arsenic-containing ores for the recovery of metals such as gold, copper or lead can cause both an occupational health hazard to smelter workers and an environmental health problem to persons living downwind from the refineries. The study reported is a follow-up to preliminary investigations of possible arsenic ingestion by native children living near a gold refinery at Yellowknife, N.W.T., Canada and of a few mine-mill workers. Instrumental neutron activation of lake water and melted snow used as drinking water as well as of scalp hair gave evidence of appreciable intake of arsenic and some mercury. A further set of 67 hair samples was obtained from most of the smelter workers and from children in a native settlement who were considered most vulnerable, augmented by a set of 26 control samples from steel workers and children living in a comparable (but arsenic-free) northern area about 1000 km distance at Whitehorse, Yukon. Hair arsenic levels were consistently elevated above the controls, ranging to 280 ppm in one worker. The water supplies ranged up to 3 ppm, well above the 0.05 ppm MPC for drinking water. A larger epidemiological study of the area and of Hay River, N.W.T. controls, done in association with electromyography, was just completed and involved a further 414 children and workers from Yellowknife and 105 from the control area. The mean hair arsenic of 6.7 ppm for the former was quite different from a result of 0.33 ppm for the Hay River group, and 33% of the Yellowknife subjects were elevated above 1 ppm but none of the controls were above this concentration. Four workers were above 100 ppm, ranging as high as 620 ppm hair arsenic

Bioindication of air pollution effects near a copper smelter in Brazil using mango trees and soil microbiological properties

International Nuclear Information System (INIS)

Klumpp, Andreas; Hintemann, Therese; Santana Lima, Josanidia; Kandeler, Ellen

2003-01-01

A field study near the copper smelter of a large industrial complex examined air pollution effects on vegetation and soil parameters in Camacari (northeast Brazil). Close to the smelter, soil pH-value was lower and total acidity as well as organic carbon contents were higher compared with a site far from the source and two reference sites. The acidification of top soil particularly and the drastically enhanced plant-available copper concentrations were caused by atmospheric deposition. High sulphur and copper deposition significantly reduced microbial biomass and altered functional diversity of soil microorganisms (arylsulphatase and xylanase). Large accumulations of sulphur, arsenic and copper were detected in mango leaves (Mangifera indica) growing downwind from the smelter suggesting potential food chain-mediated risk. - Atmospheric emissions in northeast Brazil have transformed soil pH, accumulated in soil and plants as sulphur and heavy metals, and affected the functional diversity of soil microorganisms

Bioindication of air pollution effects near a copper smelter in Brazil using mango trees and soil microbiological properties

Energy Technology Data Exchange (ETDEWEB)

Klumpp, Andreas; Hintemann, Therese; Santana Lima, Josanidia; Kandeler, Ellen

2003-12-01

A field study near the copper smelter of a large industrial complex examined air pollution effects on vegetation and soil parameters in Camacari (northeast Brazil). Close to the smelter, soil pH-value was lower and total acidity as well as organic carbon contents were higher compared with a site far from the source and two reference sites. The acidification of top soil particularly and the drastically enhanced plant-available copper concentrations were caused by atmospheric deposition. High sulphur and copper deposition significantly reduced microbial biomass and altered functional diversity of soil microorganisms (arylsulphatase and xylanase). Large accumulations of sulphur, arsenic and copper were detected in mango leaves (Mangifera indica) growing downwind from the smelter suggesting potential food chain-mediated risk. - Atmospheric emissions in northeast Brazil have transformed soil pH, accumulated in soil and plants as sulphur and heavy metals, and affected the functional diversity of soil microorganisms.

Composition and fate of mine- and smelter-derived particulates in soils from humid subtropical and semiarid areas

Science.gov (United States)

Ettler, Vojtech; Kribek, Bohdan; Mihaljevic, Martin; Vanek, Ales; Penizek, Vit; Sracek, Ondra; Mapani, Ben; Kamona, Fred; Nyambe, Imasiku

2017-04-01

Soils in the vicinity of non-ferrous metal smelters are often highly polluted by inorganic contaminants released from particulate emissions, which undergo weathering processes and release contaminants when deposited in soils. We studied the heavy mineral fraction, separated from mining- and smelter-affected topsoils, from both a humid subtropical area in the Zambian Copperbelt and a hot semi-arid area in the northern Namibia. High concentrations of metal(loid)s were detected in the studied soils: up to 1450 ppm As, 8980 ppm Cu, 4640 ppm Pb, 2620 ppm Zn. A combination of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM/EDS), and electron probe microanalysis (EPMA) helped to identify the phases forming individual metal(loid)-bearing particles. Whereas spherical particles originate from the smelting and flue gas cleaning processes, angular particles either have geogenic origins or they are windblown from the mining operations and mine waste disposal sites. Sulphides from ores and mine tailings often exhibit weathering rims in contrast to smelter-derived high-temperature sulphides (chalcocite [Cu2S], digenite [Cu9S5], covellite [CuS], non-stoichiometric quenched Cu-Fe-S phases). Soils from humid subtropical areas exhibit higher available concentrations of metal(loids), and higher frequencies of weathering features (especially for copper-bearing oxides such as delafossite [CuFeO2]) are observed. In contrast, metal(loid)s are efficiently retained in semi-arid soils, where a high proportion of non-weathered smelter slag particles and low-solubility Ca-Cu-Pb arsenates occur. Our results indicate that compared to semi-arid areas (where inorganic contaminants were rather immobile in soils despite their high concentrations) a higher potential risk exists for agriculture in mine- and smelter-affected humid subtropical areas (where metal(loid) contaminants can be highly available for the uptake by crops). This study was supported by the Czech Science

Heavy metal tolerance in Agropyron repens (L. P. Bauv. populations from the Legnica copper smelter area, Lower Silesia

Directory of Open Access Journals (Sweden)

Teresa Brej

2014-01-01

Full Text Available The copper smelter "Legnica" is one of the oldest plants in Lower Silesia. Among the few weed species spontaneously migrating to the area around the emitter there is couch grass (Agropyron repens (L. P. Bauv.. The purpose of this study was to analyse whether the local couch grass populations, growing at various distances from the smelter, differ in tolerance to heavy metals occurring in this area. The populations were tested for tolerance to five metals (Cu, Zn, Pb, Cd, Ni using the root elongation method. The highest tolerance to Pb developed in two populations localized nearest the smelter. Similarly, all populations of couch grass from the vicinity of the smelter show a high tolerance to copper, particularly the plants from the most contaminated site. The IT for the latter population is almost 1509r, even at the highest dose of Cu. For Zn a nearing IT as for Cu was obtained. Comparing the shape of IT curves for Cd, special emphasis is put on the fact that a fixed tolerance to cadmium occurs only in the population localized closest to the emitter. The analysis of Ni-tolerance curves, of which the content in local soil is minimal, does not confirm the thesis on possibility of development of co-tolerance in the surveyed populations. It appeared that stress conditions existing near the smelter do not inhibit seed production in couch grass, but prevent a successful course of their germination on polluted soil. The improvement of soil even by 50% (addition of unpolluted soil does not improve the poor process of germination in couch grass growing nearest to the smelter. Of importance is the fact that the highest number of seeds germinated on their own, polluted soil. The need of metals' content for plant germination in populations most distant from the smelter is evidenced by an almost 30% reduction of germination ability of local seeds after addition of unpolluted soil. Another significant observation was the fact that, in spite of a poor

Composition and fate of mine- and smelter-derived particles in soils of humid subtropical and hot semi-arid areas

Energy Technology Data Exchange (ETDEWEB)

Ettler, Vojtěch, E-mail: ettler@natur.cuni.cz [Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic); Johan, Zdenek [BRGM, Avenue Claude Guillemin, 45082 Orléans Cedex 2 (France); Kříbek, Bohdan; Veselovský, František [Czech Geological Survey, Geologická 6, 152 00 Praha 5 (Czech Republic); Mihaljevič, Martin [Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic); Vaněk, Aleš; Penížek, Vít [Department of Soil Science and Soil Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 21 Praha 6 (Czech Republic); Majer, Vladimír [Czech Geological Survey, Geologická 6, 152 00 Praha 5 (Czech Republic); Sracek, Ondra [Department of Geology, Faculty of Science, Palacký University in Olomouc, 17. listopadu 12, 771 46 Olomouc (Czech Republic); Mapani, Ben; Kamona, Fred [Department of Geology, Faculty of Science, University of Namibia, Private Bag 13301, Windhoek (Namibia); Nyambe, Imasiku [University of Zambia, School of Mines, P. O. Box 32 379, Lusaka (Zambia)

2016-09-01

We studied the heavy mineral fraction, separated from mining- and smelter-affected topsoils, from both a humid subtropical area (Mufulira, Zambian Copperbelt) and a hot semi-arid area (Tsumeb, Namibia). High concentrations of metal(loid)s were detected in the studied soils: up to 1450 mg As kg{sup −1}, 8980 mg Cu kg{sup −1}, 4640 mg Pb kg{sup −1}, 2620 mg Zn kg{sup −1}. A combination of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM/EDS), and electron probe microanalysis (EPMA) helped to identify the phases forming individual metal(loid)-bearing particles. Whereas spherical particles originate from the smelting and flue gas cleaning processes, angular particles have either geogenic origins or they are windblown from the mining operations and mine waste disposal sites. Sulphides from ores and mine tailings often exhibit weathering rims in contrast to smelter-derived high-temperature sulphides (chalcocite [Cu{sub 2}S], digenite [Cu{sub 9}S{sub 5}], covellite [CuS], non-stoichiometric quenched Cu–Fe–S phases). Soils from humid subtropical areas exhibit higher available concentrations of metal(loids), and higher frequencies of weathering features (especially for copper-bearing oxides such as delafossite [Cu{sup 1+} Fe{sup 3+} O{sub 2}]) are observed. In contrast, metal(loid)s are efficiently retained in semi-arid soils, where a high proportion of non-weathered smelter slag particles and low-solubility Ca–Cu–Pb arsenates occur. Our results indicate that compared to semi-arid areas (where inorganic contaminants were rather immobile in soils despite their high concentrations) a higher potential risk exists for agriculture in mine- and smelter-affected humid subtropical areas (where metal(loid) contaminants can be highly available for the uptake by crops). - Highlights: • Mining- and smelter-derived particles identified in subtropical and semi-arid soils • Sulphides, oxides, and metal-bearing arsenates most frequently encountered �

40 CFR Appendix A to Part 57 - Primary Nonferrous Smelter Order (NSO) Application

Science.gov (United States)

2010-07-01

.... Background information on the firm's organizational structure and its associated accounting and financial.... Interim control waiver requests based on the smelter's projected inability to earn adequate income after installation of interim pollution control equipment will be subject to the permanent waiver test. 1.2.3...

Modelling assessment of regional groundwater contamination due to historic smelter emissions of heavy metals

NARCIS (Netherlands)

Grift, B. van der; Griffioen, J.

2008-01-01

Historic emissions from ore smelters typically cause regional soil contamination. We developed a modelling approach to assess the impact of such contamination on groundwater and surface water load, coupling unsaturated zone leaching modelling with 3D groundwater transport modelling. Both historic

Impacts of landscape remediation on the heavy metal pollution dynamics of a lake surrounded by non-ferrous smelter waste

Energy Technology Data Exchange (ETDEWEB)

Blake, William H. [Department of Geography, University of Wales, Swansea SA2 8PP (United Kingdom)]. E-mail: william.blake@plymouth.ac.uk; Walsh, Rory P.D. [Department of Geography, University of Wales, Swansea SA2 8PP (United Kingdom); Reed, Jane M. [Department of Geography, University of Hull, Cottingham Road, Hull HU6 7RX (United Kingdom); Barnsley, Michael J. [Department of Geography, University of Wales, Swansea SA2 8PP (United Kingdom); Smith, Jamie [Department of Geography, University of Wales, Swansea SA2 8PP (United Kingdom)

2007-07-15

Heavy metal concentrations and potential bioavailability are reported for sediment in a shallow flood detention lake surrounded by reclaimed, smelter-contaminated land. A range of sediment column proxy indicators is used to explore changes in pollution dynamics with remediation. Sediment concentrations of Pb and Zn are high at {approx}600 and 20 000 mg kg{sup -1}, respectively. Less than 7% of total Pb is potentially bioavailable following sequential extraction as opposed to 47% of Zn. Metal transfer mechanisms to lake sediment include detrital inputs, scavenging by particulates and biogeochemical precipitation. Sedimentary evidence indicates that detrital inputs to the lake declined following land reclamation after which it is proposed that dissolved inputs increased with leaching of reworked waste material. Whilst downcore metal profiles may be subject to post-depositional change, diatom analysis suggests more recent improvements in water quality. The potential for post-remediation pollution episodes relating to metal release from historic sedimentary stores should be considered in future remediation strategies. - The contaminant hydrology of reworked smelter spoil is complex.

Impacts of landscape remediation on the heavy metal pollution dynamics of a lake surrounded by non-ferrous smelter waste

International Nuclear Information System (INIS)

Blake, William H.; Walsh, Rory P.D.; Reed, Jane M.; Barnsley, Michael J.; Smith, Jamie

2007-01-01

Heavy metal concentrations and potential bioavailability are reported for sediment in a shallow flood detention lake surrounded by reclaimed, smelter-contaminated land. A range of sediment column proxy indicators is used to explore changes in pollution dynamics with remediation. Sediment concentrations of Pb and Zn are high at ∼600 and 20 000 mg kg -1 , respectively. Less than 7% of total Pb is potentially bioavailable following sequential extraction as opposed to 47% of Zn. Metal transfer mechanisms to lake sediment include detrital inputs, scavenging by particulates and biogeochemical precipitation. Sedimentary evidence indicates that detrital inputs to the lake declined following land reclamation after which it is proposed that dissolved inputs increased with leaching of reworked waste material. Whilst downcore metal profiles may be subject to post-depositional change, diatom analysis suggests more recent improvements in water quality. The potential for post-remediation pollution episodes relating to metal release from historic sedimentary stores should be considered in future remediation strategies. - The contaminant hydrology of reworked smelter spoil is complex

Identification of historical lead sources in roof dust and recent lake sediments from an industrialized are: Indications from lead isotopes

International Nuclear Information System (INIS)

Chenhall, B.E.; Depers, A.M.; Jones, B.G.; Chiaradia, M.

1997-01-01

X-ray fluorescence and stable lead (Pb) isotopic analyses have been undertaken on dusts, known from microscopic investigation to contain significant quantities of industrially- and urban-derived particulate matter, present in the roof cavities of houses in the Illawarra region (N.S.W., Australia), with the objective of examining the historic record of Pb pollution. All investigated houses contained in excess of 250 μg g -1 Pb, with dwellings close to a copper smelter, in a large industrial complex including a major steelworks, containing higher (>2500 μg g -1 ) Pb concentrations. The isotopic composition in the dusts, expressed here as 206 Pb/ 204 Pb, is relatively constant at 17.0, irrespective of dwelling age or distance from the industrial complex. Contamination of the dusts by Pb sourced from paint cannot explain the isotopic uniformity of the dust samples. Isotopic modelling indicates that the dusts contain Pb derived from the copper smelter, gasoline-air Pb and a minor contribution from the steelworks. Isotopic calculations, together with records of particulate pollution emission, indicate a link between the Pb in roof dusts and Pb contamination of the near surface lagoonal sediments. Over the last five decades, atmospheric fallout of Pb-bearing particulate matter appears to have been the dominant pathway for addition of Pb to the lagoon and dwellings in the Illawarra region

Strategies for implementing zero discharge in an industrial smelter : 1. Managing fluroide in groundwater

Science.gov (United States)

Stagnitti, F.; Salzman, S.; Thwaites, L.; Allinson, G.; Le Blanc, M.; Hill, J.; Doerr, S.; de Rooij, G.

2003-04-01

The Portland Aluminium smelter produces approximately 75 ML of process wastewater each year. This is combined with storm water runoff from the site to give an annual production of 715 ML. In common with many other smelters, this wastewater stream is currently discharged to the ocean. However, although the quality of the water Portland Aluminium discharges currently meets all Australian Environmental Protection Agency license requirements, this mode of release is unlikely to be acceptable in the near future, and alternative disposal options for the water are required. The Portland smelter has developed strategies which will enable it to achieve zero-discharge within 5 years. These strategies include separating process water from storm water, recycling storm water, construction of evaporation ponds to receive process water, irrigation of process water and storm water on lands within the site and maintenance of important wetland functions. The poster presents a summary of the management strategies currently being trialed and in particular focuses on modeling the spatial and temporal variations of fluoride found in the shallow groundwater and the implications of achieving zero-discharge. The poster also discusses the possible impacts on the distribution of fluoride and other solutes in the vadose zone by the irrigation of treated process water on blue-gum plantations. Computer simulations indicate that irrigation of process water (either treated or untreated) on the land poses no significant long-term threat to regional or surficial groundwater. However the impacts of increased solute transport through the vadose zone on changes in soil structure and nutrition require further investigation.

Negotiating Family Tracking

DEFF Research Database (Denmark)

Albrechtslund, Anders; Bøge, Ask Risom; Sonne Damkjær, Maja

This presentation explores the question: What motivates the use of tracking technologies in families, and how does the use transform the relations between parent and child? The purpose is to investigate why tracking technologies are used in families and how these technologies potentially change...... the relation between parents and children. The use of tracking technologies in families implicate negotiations about the boundaries of trust and intimacy in parent-child relations which can lead to strategies of resistance or modification (Fotel and Thomsen, 2004; Rooney, 2010; Steeves and Jones, 2010......). In the presentation, we report from a qualitative study that focuses on intergenerational relations. The study draws on empirical data from workshops with Danish families as well as individual and group interviews. We aim to gain insights about the sharing habits and negotiations in intimate family relations...

Detection and removal of fluorine in the waste gases of a steel smelter and measuring air quality in its surroundings

Energy Technology Data Exchange (ETDEWEB)

Graue, G; Nagel, H

1968-01-01

Plant damage in the Duisburg area was attributed to the action of fluoride supposedly originating in industrial waste gases, particularly of steel smelters. Air quality measurements were taken near a large steel smelter for a period of three years. After eliminating errors the total concentration of fluoride in the course of 3 years was established as between 2 and 6 mg/m/sup 2/ per day. Clearly, no free fluorine is emitted by steel smelters, although gaseous fluoride compounds can occur. Downstream from metallurgical furnaces, particularly where brown smoke is emitted, this fluoride is almost completely adsorbed by the dust. Ores and other raw materials in steel smelters are liable to contain fluorides, usually in the form of fluorite. Only a small proportion of this is liberated on the sintering band. However, since the sintering waste gases are acid, less fluoride is adsorbed by dust at this point and separated during dust collection. The use of desulfurization units downstream of the sintering bands could solve this problem. If, for the time being, nothing is done in this direction, it is because the fluoride contents of these gases do not play a significant role, due to the height of the stacks in use. This is supported by the results of extensive air purity measurements in the Duisburg region, in which fluoride levels between 1 and 3 ..mu..g were found per m/sup 3/ STP of air.

Environmental impact of active and abandoned mines and metal smelters in Slovenia

Directory of Open Access Journals (Sweden)

Tomaž Budkovič

2003-06-01

Full Text Available Slovenia has long been known for its numerous mines and ore processing. From the times of the Roman Empire to now, 49 mines and open pits were opened, four of them were large (Idrija, Mežica – Topla, Litija and Žirovski vrh. There were also 25 oreprocessing plants and smelters, which were operating mostly in the vicinity of larger mines (Idrija, Žerjav, Celje. Due to the lack of written sources, we probably haven succeeded in making a complete list of them. There were 33 iron works operating in the vicinity ofmines and open pits, three large ones have further developed and are still operating (Jesenice, Ravne na Koroškem and Štore. As the ore processing capacities have far exceeded the capacities of the Slovenian mining, ore has long been imported and only processed in Slovenia. On the basis of the results of our investigations in the vicinity of larger mines and smelters we estimated that in Slovenia the areas in which critical limit for heavy metal content is exceeded sums up to about 80 km2.

Metal contamination in wildlife living near two zinc smelters

Science.gov (United States)

Beyer, W.N.; Pattee, O.H.; Sileo, L.; Hoffman, D.J.; Mulhern, B.M.

1985-01-01

Wildlife in an oak forest on Blue Mountain was studied 10 km upwind (Bake Oven Knob site) and 2 km downwind (Palmerton site) of two zinc smelters in eastern Pennsylvania, USA. Previous studies at sites near these smelters had shown changes in populations of soil microflora, lichens, green plants and litter-inhabiting arthropods. The 02 soil litter horizon at Palmerton was heavily contaminated with Pb (2700 mg kg-1), Zn (24000 mg kg-1), and Cd (710 mg kg-1), and to a lesser extent with Cu (440 mg kg-1). Various kinds of invertebrates (earthworms, slugs and millipedes) that feed on soil litter or soil organic matter were rare at, or absent from, the Palmerton site. Those collected at Bake Oven Knob tended to have much higher concentrations of metals than did other invertebrates. Frogs, toads and salamanders were very rare at, or absent from, the Palmerton site, but were present at Bake Oven Knob and at other sites on Blue Mountain farther from the smelters. Metal concentrations (dry wt) in different organisms from Palmerton were compared. Concentrations of Pb were highest in shrews (110 mg kg-1), followed by songbirds (56 mg kg-1), leaves (21 mg kg-1), mice (17 mg kg-1), carrion insects (14 mg kg-1), berries (4.0 mg kg-1), moths (4,3 mg kg-1) and fungi (3.7 mg kg-1). Concentrations of Cd, in contrast, were highest in carrion insects (25 mg kg-1 ),followed by fungi (9.8 mg kg-1), leaves (8.1 mg kg-1), shrews (7.3 mg kg-I), moths (4.9 mg kg-1), mice (2.6 mg kg -1), songbirds (2.5 mg kg -1) and berries (1.2 mg kg-1). Concentrations of Zn and Cu tended to be highest in the same organisms that had the highest concentrations of Cd. Only a small proportion of the metals in the soil became incorporated into plant foliage, and much of the metal contamination detected in the biota probably came from aerial deposition. The mice from both sites seemed to be healthy. Shrews had higher concentrations of metals than did mice, and one shrew showed evidence of Pb poisoning; its red

Transformation of arsenic-rich copper smelter flue dust in contrasting soils: A 2-year field experiment

Czech Academy of Sciences Publication Activity Database

Jarošíková, A.; Ettler, V.; Mihaljevič, M.; Penížek, V.; Matoušek, Tomáš; Culka, A.; Drahota, P.

2018-01-01

Roč. 237, JUN (2018), s. 83-92 ISSN 0269-7491 Institutional support: RVO:68081715 Keywords : arsenic * smelter dust * soil Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 5.099, year: 2016

Thyroid function in smelters after long-term exposure to heavy metals; Funkcja tarczycy u hutnikow dlugoletnio narazonych na metale ciezkie

Energy Technology Data Exchange (ETDEWEB)

Andrzejak, R.; Antonowicz, J.; Bolanowska, B.; Kabacinska-Knapik, D.; Hebdzinski, L.; Smolik, R. [Przychodnia Przyzakladowa Huty Miedzi `Legnica`, Legnica (Poland)

1996-12-31

In the year 1995 in a group of 93 male workers of a copper smelter (mean age = 40.7 years, exposure time = 8.5 years) following parameters were measured: blood levels of: lead and cadmium; serum levels of copper, zinc, calcium and magnesium-with use of atomic absorption spectrophotometry; FEP -with Piomelli`s method; and T3, T4 and TSH in serum with radioimmunometric method. Mean blood lead level was 38.2 micrograms/dl, and concentrations of other metals and hormones were within norm limits. Mean level of FEP was slightly above norm (FEP = 106.5 micrograms/100 ml E). We found no correlation between investigated hormones (T3, T4 and TSH) and age, length of exposure nor blood lead level. We found a significant inverse correlation between FEP and TSH (r = -0.207; p < 0.047). This correlation could point to the fact that lead burden (expressed not in the actual blood level but in the FEP concentration) could negatively influence endocrine functions through hypothalamic-pituitary axis. (author). 18 refs, 1 fig., 1 tab.

Assessment of Fluoride Concentration of Soil and Vegetables in Vicinity of Zinc Smelter, Debari, Udaipur, Rajasthan.

Science.gov (United States)

Bhat, Nagesh; Jain, Sandeep; Asawa, Kailash; Tak, Mridula; Shinde, Kushal; Singh, Anukriti; Gandhi, Neha; Gupta, Vivek Vardhan

2015-10-01

As of late, natural contamination has stimulated as a reaction of mechanical and other human exercises. In India, with the expanding industrialization, numerous unsafe substances are utilized or are discharged amid generation as cleans, exhaust, vapours and gasses. These substances at last are blended in the earth and causes health hazards. To determine concentration of fluoride in soils and vegetables grown in the vicinity of Zinc Smelter, Debari, Udaipur, Rajasthan. Samples of vegetables and soil were collected from areas situated at 0, 1, 2, 5, and 10 km distance from the zinc smelter, Debari. Three samples of vegetables (i.e. Cabbage, Onion and Tomato) and 3 samples of soil {one sample from the upper layer of soil (i.e. 0 to 20 cm) and one from the deep layer (i.e. 20 - 40 cm)} at each distance were collected. The soil and vegetable samples were sealed in clean polythene bags and transported to the laboratory for analysis. One sample each of water and fertilizer from each distance were also collected. The mean fluoride concentration in the vegetables grown varied between 0.36 ± 0.69 to 0.71 ± 0.90 ppm. The fluoride concentration in fertilizer and water sample from various distances was found to be in the range of 1.4 - 1.5 ppm and 1.8 - 1.9 ppm respectively. The fluoride content of soil and vegetables was found to be higher in places near to the zinc smelter.

Analysis of metal(loid)s contamination and their continuous input in soils around a zinc smelter: Development of methodology and a case study in South Korea.

Science.gov (United States)

Yun, Sung-Wook; Baveye, Philippe C; Kim, Dong-Hyeon; Kang, Dong-Hyeon; Lee, Si-Young; Kong, Min-Jae; Park, Chan-Gi; Kim, Hae-Do; Son, Jinkwan; Yu, Chan

2018-07-01

Soil contamination due to atmospheric deposition of metals originating from smelters is a global environmental problem. A common problem associated with this contamination is the discrimination between anthropic and natural contributions to soil metal concentrations: In this context, we investigated the characteristics of soil contamination in the surrounding area of a world class smelter. We attempted to combine several approaches in order to identify sources of metals in soils and to examine contamination characteristics, such as pollution level, range, and spatial distribution. Soil samples were collected at 100 sites during a field survey and total concentrations of As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, and Zn were analyzed. We conducted a multivariate statistical analysis, and also examined the spatial distribution by 1) identifying the horizontal variation of metals according to particular wind directions and distance from the smelter and 2) drawing a distribution map by means of a GIS tool. As, Cd, Cu, Hg, Pb, and Zn in the soil were found to originate from smelter emissions, and As also originated from other sources such as abandoned mines and waste landfill. Among anthropogenic metals, the horizontal distribution of Cd, Hg, Pb, and Zn according to the downwind direction and distance from the smelter showed a typical feature of atmospheric deposition (regression model: y = y 0  + αe -βx ). Lithogenic Fe was used as an indicator, and it revealed the continuous input and accumulation of these four elements in the surrounding soils. Our approach was effective in clearly identifying the sources of metals and analyzing their contamination characteristics. We believe this study will provide useful information to future studies on soil pollution by metals around smelters. Copyright © 2018 Elsevier Ltd. All rights reserved.

NA49 event display of the reconstructed tracks emanating from the "little bang" created in a central collision of Lead projectile with a Lead nucleus

CERN Document Server

1996-01-01

When a 33 TeV Lead nucleous projectile hits head on a Lead target it creates for a brief instant of time a system of quarks and gluons that more than 100'000 times hotter than the sun. As this fireball expands it reconstitutes normal matter creating thousands of particles (pions, kaons, protons, ....). The NA49 Time Projection Chambers extending over 13 m can record a large majority of the produced charged particles. The result of a complex analysis is shown here in a event display of the reconstructed tracks. The blue lines represent the boundaries of the detectors in a perspective view from the far end of the experiment towards the interaction point, where all the tracks originate.

Lead exposure of the child population in Greece.

Science.gov (United States)

Maravelias, C; Athanaselis, S; Poulos, L; Alevisopoulos, G; Ewers, U; Koutselinis, A

1994-12-18

Lead exposure of the child population was studied in three different areas in Greece: Kalamata which is a rural area of Southern Greece; Tavros, a district of Athens with a considerable industrial activity; and Lavrion, a small city near Athens where a lead-zinc mining and smelting industrial complex has existed for more than 90 years. The results were evaluated with respect to a number of individual, social and environmental variables (i.e. smelter, occupation of the father) especially those concerning the area of Lavrion which is the most heavily polluted area in Greece. The results of this study can be considered as an index for the extent of the lead pollution problem in the named areas of Greece.

Relative tracking control of constellation satellites considering inter-satellite link

Science.gov (United States)

Fakoor, M.; Amozegary, F.; Bakhtiari, M.; Daneshjou, K.

2017-11-01

In this article, two main issues related to the large-scale relative motion of satellites in the constellation are investigated to establish the Inter Satellite Link (ISL) which means the dynamic and control problems. In the section related to dynamic problems, a detailed and effective analytical solution is initially provided for the problem of satellite relative motion considering perturbations. The direct geometric method utilizing spherical coordinates is employed to achieve this solution. The evaluation of simulation shows that the solution obtained from the geometric method calculates the relative motion of the satellite with high accuracy. Thus, the proposed analytical solution will be applicable and effective. In the section related to control problems, the relative tracking control system between two satellites will be designed in order to establish a communication link between the satellites utilizing analytical solution for relative motion of satellites with respect to the reference trajectory. Sliding mode control approach is employed to develop the relative tracking control system for body to body and payload to payload tracking control. Efficiency of sliding mode control approach is compared with PID and LQR controllers. Two types of payload to payload tracking control considering with and without payload degree of freedom are designed and suitable one for practical ISL applications is introduced. Also, Fuzzy controller is utilized to eliminate the control input in the sliding mode controller.

Sampling strong tracking nonlinear unscented Kalman filter and its application in eye tracking

International Nuclear Information System (INIS)

Zu-Tao, Zhang; Jia-Shu, Zhang

2010-01-01

The unscented Kalman filter is a developed well-known method for nonlinear motion estimation and tracking. However, the standard unscented Kalman filter has the inherent drawbacks, such as numerical instability and much more time spent on calculation in practical applications. In this paper, we present a novel sampling strong tracking nonlinear unscented Kalman filter, aiming to overcome the difficulty in nonlinear eye tracking. In the above proposed filter, the simplified unscented transform sampling strategy with n + 2 sigma points leads to the computational efficiency, and suboptimal fading factor of strong tracking filtering is introduced to improve robustness and accuracy of eye tracking. Compared with the related unscented Kalman filter for eye tracking, the proposed filter has potential advantages in robustness, convergence speed, and tracking accuracy. The final experimental results show the validity of our method for eye tracking under realistic conditions. (classical areas of phenomenology)

Effects of emission reductions from the smelters in Sudbury on recovery of lakes within the metal deposition zone

Energy Technology Data Exchange (ETDEWEB)

Keller, W.; Heneberry, J.; Clark, M.; Malette, M.; Gunn, J. [Laurentian Univ., Sudbury, ON (Canada) Dept. of Biology

1999-07-01

Recent trends are examined in the chemistry of Sudbury lakes for evidence of further chemical recovery, as well as some of the biological characteristics of recovering Sudbury lakes. Preliminary results are provided from studies investigating physical, chemical and biological factors that may influence the lake recovery process with a focus on the lakes close to Sudbury that were historically the most severely affected. Smelter emission reductions in the Sudbury area have led to substantial changes in the water quality of area lakes, and decreases in acidity, sulfate, and copper and nickel concentrations followed the substantial decreases in emissions during the 1970s and similar trends are continuing after the implementation of large additional smelter emission reductions in the 1990s. Some of the most highly affected lakes close to the Sudbury smelters have showed very dramatic reductions in acidity and metal concentrations during the 1990s. Evaluation of the direct effects of the recent emissions reductions is confounded by the potential continuing effects of previous emission reductions and the effects of weather variations on chemistry time trends in Sudbury lakes. Continued monitoring of Sudbury lakes is essential to evaluate the ultimate effect of emission reduction programs, to develop an understanding of the recovery process, and to determine the need for any additional emission reduction requirements. 38 refs., 7 figs.

Economic cost of electricity sold to new aluminium smelters

International Nuclear Information System (INIS)

Belanger, G.; Bernard, J.T.

2008-01-01

Low cost electricity was a key factor for establishing an aluminium industry in Quebec. Smelters in the province use 50 terawatt hours of electricity per year, which represents 25 per cent of the total consumed in Quebec. This article assessed the profitability of new industrial projects that require large quantities of electricity at a time when the cost of new power plants is increasing. However, electricity is being sold below cost and the difference is subsidized by the government. The investment is justified by the government because these new projects create high paying jobs. The authors presented cases of 2 new aluminium plants, and concluded that they represented a very high economic cost for the province. 1 tab

Removal of Arsenic from Wastewaters by Airlift Electrocoagulation: Part 3: Copper Smelter Wastewater Treatment

DEFF Research Database (Denmark)

Hansen, H.K.; Ottosen, Lisbeth M.

2010-01-01

The arsenic content in wastewater is of major concern for copper smelters. A typical complex wastewater treatment is needed with a combination of chemical and physical processes. Electrocoagulation (EC) has shown its potential for arsenic removal due to the formation of ferric hydroxide-arsenate ...... threshold value for wastewater discharge could rapidly be reached when the conventional method did not clean the wastewater sufficiently....

Editorial: Lead Risk Assessment and Health Effects

Directory of Open Access Journals (Sweden)

Howard W. Mielke

2016-06-01

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

Track reconstruction in the emulsion-lead target of the OPERA experiment using the ESS microscope

Science.gov (United States)

Arrabito, L.; Bozza, C.; Buontempo, S.; Consiglio, L.; Cozzi, M.; D'Ambrosio, N.; DeLellis, G.; DeSerio, M.; Di Capua, F.; Di Ferdinando, D.; Di Marco, N.; Ereditato, A.; Esposito, L. S.; Fini, R. A.; Giacomelli, G.; Giorgini, M.; Grella, G.; Ieva, M.; Janicsko Csathy, J.; Juget, F.; Kreslo, I.; Laktineh, I.; Manai, K.; Mandrioli, G.; Marotta, A.; Migliozzi, P.; Monacelli, P.; Moser, U.; Muciaccia, M. T.; Pastore, A.; Patrizii, L.; Petukhov, Y.; Pistillo, C.; Pozzato, M.; Romano, G.; Rosa, G.; Russo, A.; Savvinov, N.; Schembri, A.; Scotto Lavina, L.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Strolin, P.; Tioukov, V.; Waelchli, T.

2007-05-01

The OPERA experiment, designed to conclusively prove the existence of νμ→ντ oscillations in the atmospheric sector, makes use of a massive lead-nuclear emulsion target to observe the appearance of ντ's in the CNGS νμ beam. The location and analysis of the neutrino interactions in quasi real-time required the development of fast computer-controlled microscopes able to reconstruct particle tracks with sub-micron precision and high efficiency at a speed of ~20 cm2/h. This paper describes the performance in particle track reconstruction of the European Scanning System, a novel automatic microscope for the measurement of emulsion films developed for OPERA.

Track reconstruction in the emulsion-lead target of the OPERA experiment using the ESS microscope

International Nuclear Information System (INIS)

Arrabito, L; Bozza, C; Buontempo, S

2007-01-01

The OPERA experiment, designed to conclusively prove the existence of ν μ →ν τ oscillations in the atmospheric sector, makes use of a massive lead-nuclear emulsion target to observe the appearance of ν τ 's in the CNGS ν μ beam. The location and analysis of the neutrino interactions in quasi real-time required the development of fast computer-controlled microscopes able to reconstruct particle tracks with sub-micron precision and high efficiency at a speed of ∼20 cm 2 /h. This paper describes the performance in particle track reconstruction of the European Scanning System, a novel automatic microscope for the measurement of emulsion films developed for OPERA

Better track leads to new particles

CERN Multimedia

2006-01-01

"Dutch researcher Thijs Cornelissen developed an algorithm to reconstruct the particle tracks and that is being used in a European research institute for particle physics. His method provides greater insights into the origine of particles that arise as a result of collisions." (1/2 page)

Arsenic exposure to smelter workers. Clinical and neurophysiological studies

Energy Technology Data Exchange (ETDEWEB)

Blom, S.; Lagerkvist, B.; Linderholm, H.

1985-08-01

Forty-seven copper smelter workers, exposed to airborne arsenic for 8-40 years, were examined clinically with electromyography, and the motor and sensory conduction velocities in their arms and legs were determined. Fifty age-matched industrial workers not exposed to arsenic formed a reference group. The level of arsenic in the air at the smeltery was estimated to be below 500 micrograms/mT before 1975 and approximately 50 micrograms/mT thereafter. Urine analyses of arsenic showed a mean value of 71 micrograms/l (1 mumol/l) in the exposed group; this value is lower than that found in earlier studies reporting clinically detectable neuropathy. A slightly reduced nerve conduction velocity in two or more peripheral nerves was more common among the arsenic workers than the referents, and a statistically significant correlation between cumulative exposure to arsenic and reduced nerve conduction velocity in three peripheral motor nerves was found. This occurrence was interpreted as a sign of slight subclinical neuropathy. In conclusion the risk of clinically significant neuropathy is small when exposure is kept below 50 micrograms/mT in workroom air. The subclinical findings may be of interest in relation to the prevention of early adverse health effects from arsenic exposure.

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

The potential of elemental and isotopic analysis of tree bark for discriminating sources of airborne lead contamination in the UK.

Science.gov (United States)

Bellis, D; McLeod, C W; Satake, K

2001-02-01

Samples of tree bark, which accumulate airborne material, were collected from seven locations in the UK to provide an indication of the magnitude and source of lead pollution. Measurement of the Pb content and 206/207Pb stable isotope ratio by inductively coupled plasma mass spectrometry revealed significant differences between the sites. The concentration of Pb varied over almost four orders of magnitude from 7.2 to 9,600 micrograms g-1, the maximum values being found near a 'secondary' Pb smelter. The 206/207Pb isotope ratios varied from 1.108 +/- 0.002 to 1.169 +/- 0.001. The lowest Pb concentrations and highest isotope ratios were detected in bark samples from the Scilly Isles, reflecting the low-level of industry and road traffic. In contrast, samples obtained from a city centre (Sheffield) and near a motorway (M1) contained 25-46 micrograms g-1 Pb and recorded the lowest 206/207Pb ratios. Higher concentrations in the vicinity of a coal-fired power station recorded a 206/207Pb ratio of 1.14, suggesting a significant contribution from fly-ash. The relative contribution of lead from petrol (206/207Pb = 1.08) and other sources such as coal (206/207Pb = 1.18) were thus estimated using mass balance equations. Tree bark near the lead smelter recorded an intermediate 206/207Pb ratio of 1.13 reflecting the processing of material of mixed origin.

Tracking health-related Sustainable Development Goals (SDGs in Nepal

Directory of Open Access Journals (Sweden)

Meghnath Dhimal

2017-07-01

Full Text Available Sustainable Development Goals (SDGs comprise of 17 goals and 169 targets. All SDGs are interlinked to produce synergetic eff ects and emphasize health in all policies. Among the 17 Goals, Goal 3 has a central focus on health, which is underpinned by 13 targets. The other 16 goals are also directly or indirectly related to health and will contribute to achieving the associated targets for Goal 3. The ambitious SDG agenda and their progress can be tracked by measuring numerous goals, targets, and indicators. The main objective of this paper is to provide an overview about how health- related SDGs and their targets and indicators are being tracked in the national context of Nepal. Adequate investment in research for knowledge generation, capacity building and innovation, and continous research communication among policy makers, researchers and external development partners will contribute to tracking the progress of SDGs in Nepal.

Preliminary analysis of levels of arsenic and other metalic elements in PM10 sampled near Copper Smelter Bor (Serbia

Directory of Open Access Journals (Sweden)

Renata Kovačević

2010-09-01

Full Text Available In this paper, the levels of twenty one elements (Ag, Al, As, B, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, S, Se, Sr and Zn in PM10 are presented, as well as SO2 concentration, measured at the sampling site in an urban area of the town of Bor (40,000 inhabitants in eastern Serbia. The sampling site was located in a densely populated city center about 0.65 km away from one of the largest copper mines and copper smelters in Europe. For the first time PM10 was collected using the European standard sampler, during a preliminary campaign in duration of 7 days in early spring 2009. PM10 were sampled on PTFE membrane filters and element concentrations were quantified by GF AAS and ICP AES. Concentration levels and correlations within trace elements, PM10 and SO2 indicated that industrial activities underpinned with meteorological conditions of low wind speed (calm are the main factors that influence air pollution in a densely populated area. It was evident that both PM10 mass concentration and SO2 concentration once exceeded the daily limit values during a measuring period of seven days. Strong relationship was found between PM10 and Mn, Mg, Ca and B daily average concentrations. On the other hand, SO2 correlated strongly with As, Pb, Cd, Cu and S daily average concentrations. These results confirm the relationship between emissions of SO2 from the Copper Smelter Bor and calm meteorological conditions (wind speed less than 0.5 m/sec with the concentration levels of carcinogenic substances of arsenic, lead and cadmium in ambient air.

Smelters as Analogs for a Volcanic Eruption at Yucca Mountain

International Nuclear Information System (INIS)

Ross, Benjamin

2004-01-01

The distribution of trace radionuclides in secondary metal smelters provides an analog for spent fuel released from packages during a volcanic eruption. The fraction of the inventory of a radionuclide that would be released into the air in a volcanic eruption is called the dust partitioning factor. In consequence analyses of a volcanic eruption at Yucca Mountain, a value of one has been used for this parameter for all elements. This value is too high for the refractory elements. Reducing the dust partitioning factor for refractory elements to a value equal to the fraction of the magma that becomes ash would still yield conservative estimates of how much radioactivity would be released in an eruption

Tracking historical lead pollution in the coastal area adjacent to the Yangtze River Estuary using lead isotopic compositions

International Nuclear Information System (INIS)

Hao Yunchao; Guo Zhigang; Yang Zuosheng; Fan, Dejiang; Fang Ming; Li Xiangdong

2008-01-01

The rapid economic development in the Yangtze River Delta (YRD), China in the last three decades has had a significant impact on the environment of the East China Sea (ECS). Lead isotopic compositions of a 210 Pb dated sediment core collected from the coastal ECS adjacent to the Yangtze River Estuary were analyzed to track the Pb pollution in the region. The baseline Pb concentration in the coastal ECS sediments before the industrialization in China was 32 μg g -1 , and the corresponding 206 Pb/ 207 Pb ratio was 1.195. The high-resolution profiles of Pb flux and 206 Pb/ 207 Pb ratios had close relationships with the economic development and the history of the use of leaded gasoline in China, and they were clearly different from those of most European countries and United States. - The combination of Pb concentration, sedimentary flux, Pb isotopic composition and 210 Pb dating in the coastal ECS sediments revealed the historical Pb pollution in China

Characterisation of airborne particulate pollution in the Cu smelter and former mining town of Karabash, South Ural Mountains of Russia.

Science.gov (United States)

Williamson, B J; Udachin, V; Purvis, O W; Spiro, B; Cressey, G; Jones, G C

2004-11-01

Airborne total suspended particulates (TSP), dusts from smelter blast furnace and converter stacks, and filtrates of snow melt waters have been characterised in the Cu smelter and former mining town of Karabash, Russia. TSP was collected at sites up- and downwind of the smelter and large waste and tailings dumps (Oct. 2000 and July 2001). Methods for particle size, mineralogical and elemental determinations have been tested and described, and a new PSD-MicroSOURCE XRD technique developed for the mineralogical analysis of microsamples on filter substrates. TSP in downwind samples has a mean equivalent spherical diameter of 0.5 microm (s.d. = 0.2) and was found to be 100% respirable. The main element of human health/environmental concern, above Russian maximum permitted levels (1 microg m(-3), average over any time period), was Pb which was measured at 16-30 microg m(-3) in downwind samples. Individual particulates mainly consisted of complex mixtures of anglesite (PbSO4), Zn2SnO4 and poorly ordered Zn sulphates. From experimental and theoretical considerations, a high proportion of contained Pb, Zn, Cd and As in this material is considered to be in a readily bioavailable form. Chemical and mineralogical differences between the TSP, stack dusts and snow samples are discussed, as well as the implications for human and regional environmental health.

Lead and cadmium in mushrooms from the vicinity of two large emission sources in Slovenia

International Nuclear Information System (INIS)

Petkovšek, Samar Al Sayegh; Pokorny, Boštjan

2013-01-01

Cd and Pb contents were determined in 699 samples of fruiting bodies of 55 mushrooms species, collected in the period 2000–2007 in the vicinity of the largest Slovenian thermal power plant (the Šalek Valley) and near an abandoned lead smelter (the Upper Meža Valley). The present study is the first regarding lead and cadmium in mushrooms from those exposed areas. Therefore, there was a significant lack of prior data. Among 55 studied mushroom species 36 species are edible and important from an ecotoxicological perspective. However, the remaining non-edible species are important for bioindication and allowed us to compare our results with other studies carried out in other polluted areas in Europe. The highest contents of Cd were found in Agaricus arvensis Schff.: Fr. (117 mg/kg dw) and Agaricus silvicola L.: Fr. (67.9 mg/kg dw), while the highest contents of Pb were found in Macrolepiota procera (Scop.) Singer (53.8 mg/kg dw) and Lycoperdon perlatum Pers. (50 mg/kg dw), respectively. Considering the high contents of both metals in fruiting bodies of edible fungi, together with FAO/WHO directives on tolerable levels of weekly intake of Pb/Cd by humans, it is evident that consumption of some mushroom species originating from both study areas may pose a significant human health risk. A. arvensis Schff.: Fr., A. silvicola L.: Fr. and Cortinarius caperatus (Pers.) Fr. originating from the Šalek Valley, and Armillaria mellea Vahl. P. Kumm., Boletus edulis Bull., L. perlatum Pers., Leccinum versipelle (Fr. and Hök) Snell, and M. procera (Scop.) Singer originating from the Upper Meža Valley should not be consumed at all. Our findings are consistent with some other studies, which emphasized that mushrooms from heavily polluted areas, such as in the vicinity of smelters, accumulate extremely high amounts of metals, and should therefore be omitted from human consumption. - Highlights: ► The Pb contents were higher in saprophytic fungi in comparison with mycorrhizal

76 FR 49324 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

Science.gov (United States)

2011-08-10

... operated copper and lead smelters and a lead-zinc flotation mill. In the early years of IS&R operation... tailing impoundment. The copper smelter was closed in 1946, followed by the closure of the lead-zinc flotation mill in 1968 and the lead smelter in 1972. With the exception of a few incidental buildings, the...

Stability and leaching of cobalt smelter fly ash

DEFF Research Database (Denmark)

Vítková, Martina; Hyks, Jiri; Ettler, Vojtěch

2013-01-01

The leaching behaviour of fly ash from a Co smelter situated in the Zambian Copperbelt was studied as a function of pH (5–12) using the pH-static leaching test (CEN/TS 14997). Various experimental time intervals (48h and 168h) were evaluated. The leaching results were combined with the ORCHESTRA...... modelling framework and a detailed mineralogical investigation was performed on the original FA and leached solid residues. The largest amounts of Co, Cu, Pb and Zn were leached at pH 5, generally with the lowest concentrations between pH 9 and 11 and slightly increased concentrations at pH 12. For most...... detected using SEM/EDS and/or TEM/EDS. The leaching of metals was mainly attributed to the dissolution of metallic particles. Partial dissolution of silicate and glass fractions was assumed to significantly influence the release of Ca, Mg, Fe, K, Al and Si as well as Cu, Co and Zn. The formation of illite...

Isotopically constrained lead sources in fugitive dust from unsurfaced roads in the southeast Missouri mining district

Science.gov (United States)

Witt, Emitt C.; Pribil, Michael; Hogan, John P; Wronkiewicz, David

2016-01-01

The isotopic composition of lead (Pb) in fugitive dust suspended by a vehicle from 13 unsurfaced roads in Missouri was measured to identify the source of Pb within an established long-term mining area. A three end-member model using 207Pb/206Pb and concentration as tracers resulted in fugitive dust samples plotting in the mixing field of well characterized heterogeneous end members. End members selected for this investigation include the 207Pb/206Pb for 1) a Pb-mixture representing mine tailings, 2) aerosol Pb-impacted soils within close proximity to the Buick secondary recycling smelter, and 3) an average of soils, rock cores and drill cuttings representing the background conditions. Aqua regia total concentrations and 207Pb/206Pb of mining area dust suggest that 35.4–84.3% of the source Pb in dust is associated with the mine tailings mixture, 9.1–52.7% is associated with the smelter mixture, and 0–21.6% is associated with background materials. Isotope ratios varied minimally within the operational phases of sequential extraction suggesting that mixing of all three Pb mixtures occurs throughout. Labile forms of Pb were attributed to all three end members. The extractable carbonate phase had as much as 96.6% of the total concentration associated with mine tailings, 51.8% associated with smelter deposition, and 34.2% with background. The next most labile geochemical phase (Fe + Mn Oxides) showed similar results with as much as 85.3% associated with mine tailings, 56.8% associated with smelter deposition, and 4.2% associated with the background soil.

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...

Bio-processing of copper from combined smelter dust and flotation concentrate: A comparative study on the stirred tank and airlift reactors

Energy Technology Data Exchange (ETDEWEB)

Vakylabad, Ali Behrad, E-mail: alibehzad86@yahoo.co.uk [Department of Mining Engineering, Shahid Bahonar University, Kerman (Iran, Islamic Republic of); Engineers of Nano and Bio Advanced Sciences Company (ENBASCo.), ATIC, Mohaghegh University (Iran, Islamic Republic of); Schaffie, Mahin [Department of Chemical Engineering, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Mineral Industries Research Centre (MIRC), Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Ranjbar, Mohammad [Department of Mining Engineering, Shahid Bahonar University, Kerman (Iran, Islamic Republic of); Mineral Industries Research Centre (MIRC), Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Manafi, Zahra [Sarcheshmeh Copper Complex, National Iranian Copper Industry Company (Iran, Islamic Republic of); Darezereshki, Esmaeel [Mineral Industries Research Centre (MIRC), Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Energy and Environmental Engineering Research Center (EERC), Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of)

2012-11-30

Highlights: Black-Right-Pointing-Pointer Flotation concentrate and smelter dust were sampled and combined. Black-Right-Pointing-Pointer Copper bioleaching from the combined was investigated. Black-Right-Pointing-Pointer Two bio-reactors were investigated and optimized: stirred and airlift. Black-Right-Pointing-Pointer STRs had better technical conditions and situations for bacterial leaching. - Abstract: To scrutinize the influence of the design and type of the bioreactors on the bioleaching efficiency, the bioleaching were evaluated in a batch airlift and a batch stirred tank bioreactors with mixed mesophilic and mixed moderately thermophilic bacteria. According to the results, maximum copper recoveries were achieved using the cultures in the stirred tank bioreactors. It is worth noting that the main phase of the flotation concentrate was chalcopyrite (as a primary sulphide), but the smelter dust mainly contained secondary copper sulphides such as Cu{sub 2}S, CuS, and Cu{sub 5}FeS{sub 4}.Under optimum conditions, copper dissolution from the combined flotation concentrate and smelter dust (as an environmental hazard) reached 94.50% in the STR, and 88.02% in the airlift reactor with moderately thermophilic, after 23 days. Also, copper extractions calculated for the bioleaching using mesophilic bacteria were 48.73% and 37.19% in the STR (stirred tank reactor) and the airlift bioreactor, respectively. In addition, the SEM/EDS, XRD, chemical, and mineralogical analyses and studies confirmed the above results.

Bio-processing of copper from combined smelter dust and flotation concentrate: A comparative study on the stirred tank and airlift reactors

International Nuclear Information System (INIS)

Vakylabad, Ali Behrad; Schaffie, Mahin; Ranjbar, Mohammad; Manafi, Zahra; Darezereshki, Esmaeel

2012-01-01

Highlights: ► Flotation concentrate and smelter dust were sampled and combined. ► Copper bioleaching from the combined was investigated. ► Two bio-reactors were investigated and optimized: stirred and airlift. ► STRs had better technical conditions and situations for bacterial leaching. - Abstract: To scrutinize the influence of the design and type of the bioreactors on the bioleaching efficiency, the bioleaching were evaluated in a batch airlift and a batch stirred tank bioreactors with mixed mesophilic and mixed moderately thermophilic bacteria. According to the results, maximum copper recoveries were achieved using the cultures in the stirred tank bioreactors. It is worth noting that the main phase of the flotation concentrate was chalcopyrite (as a primary sulphide), but the smelter dust mainly contained secondary copper sulphides such as Cu 2 S, CuS, and Cu 5 FeS 4 .Under optimum conditions, copper dissolution from the combined flotation concentrate and smelter dust (as an environmental hazard) reached 94.50% in the STR, and 88.02% in the airlift reactor with moderately thermophilic, after 23 days. Also, copper extractions calculated for the bioleaching using mesophilic bacteria were 48.73% and 37.19% in the STR (stirred tank reactor) and the airlift bioreactor, respectively. In addition, the SEM/EDS, XRD, chemical, and mineralogical analyses and studies confirmed the above results.

Probing the distribution and contamination levels of 10 trace metal/metalloids in soils near a Pb/Zn smelter in Middle China.

Science.gov (United States)

Li, Zhonggen; Feng, Xinbin; Bi, Xiangyang; Li, Guanghui; Lin, Yan; Sun, Guangyi

2014-03-01

The horizontal and vertical distribution patterns and contamination status of ten trace metal/metalloids (Ag, Bi, Co, Cr, Ge, In, Ni, Sb, Sn, Tl) in soils around one of the largest Chinese Pb-Zn smelter in Zhuzhou City, Central China, were revealed. Different soil samples were collected from 11 areas, including ten agricultural areas and one city park area, with a total of 83 surface soil samples and six soil cores obtained. Trace metal/metalloids were determined by inductively coupled plasma-mass spectrometry after digestion by an acid mixture of HF and HNO3. The results showed that Ag, Bi, In, Sb, Sn, and Tl contents decreased both with the distance to the Pb-Zn smelter as well as the soil depth, hinting that these elements were mainly originated from the Pb-Zn smelting operations and were introduced into soils through atmospheric deposition. Soil Ge was influenced by the smelter at a less extent, while the distributions of Co, Cr, and Ni were roughly even among most sampling sites and soil depths, suggesting that they were primarily derived from natural sources. The contamination status, as revealed by the geo-accumulation index (I geo), indicated that In and Ag were the most enriched elements, followed by Sb, Bi, and Sn. In general, Cr, Tl, Co, Ni, and Ge were of an uncontaminated status.

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

Science.gov (United States)

Sullivan, Marianne; Green, Donna

2016-01-06

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

The Impact of a Nickel-Copper Smelter on Concentrations of Toxic Elements in Local Wild Food from the Norwegian, Finnish, and Russian Border Regions.

Science.gov (United States)

Hansen, Martine D; Nøst, Therese H; Heimstad, Eldbjørg S; Evenset, Anita; Dudarev, Alexey A; Rautio, Arja; Myllynen, Päivi; Dushkina, Eugenia V; Jagodic, Marta; Christensen, Guttorm N; Anda, Erik E; Brustad, Magritt; Sandanger, Torkjel M

2017-06-28

Toxic elements emitted from the Pechenganickel complex on the Kola Peninsula have caused concern about potential effects on local wild food in the border regions between Norway, Finland and Russia. The aim of this study was to assess Ni, Cu, Co, As, Pb, Cd, and Hg concentrations in local wild foods from these border regions. During 2013-2014, we collected samples of different berry, mushroom, fish, and game species from sites at varying distances from the Ni-Cu smelter in all three border regions. Our results indicate that the Ni-Cu smelter is the main source of Ni, Co, and As in local wild foods, whereas the sources of Pb and Cd are more complex. We observed no consistent trends for Cu, one of the main toxic elements emitted by the Ni-Cu smelter; nor did we find any trend for Hg in wild food. Concentrations of all investigated toxic elements were highest in mushrooms, except for Hg, which was highest in fish. EU maximum levels of Pb, Cd, and Hg were exceeded in some samples, but most had levels considered safe for human consumption. No international thresholds exist for the other elements under study.

Local survival of pied flycatcher males and females in a pollution gradient of a Cu smelter

International Nuclear Information System (INIS)

Eeva, T.; Hakkarainen, H.; Belskii, E.

2009-01-01

Survival is one of the most central population measures when the effects of the pollution are studied in natural bird populations. However, only few studies have actually measured rigorous survival estimates on adult birds. In recent years there has been a methodological advance in survival analyses by mark-recapture models. We modelled local survival (including mortality and emigration) with the program MARK in a population of a small insectivorous passerine bird, the pied flycatcher (Ficedula hypoleuca), around a point source of heavy metals. The local survival of females in the polluted area was about 50% lower than in the other areas. Males, however, survived relatively well in the heavily polluted area, but showed somewhat lower survival in the moderately polluted area. Different pollution effects between two sexes might be due to pollution-related differences in reproductive effort in females and males, and/or more intensive uptake of heavy metals by laying females. - Female pied flycatchers (Ficedula hypoleuca) show decreased local survival around a copper smelter.

Optimized swimmer tracking system based on a novel multi-related-targets approach

Science.gov (United States)

Benarab, D.; Napoléon, T.; Alfalou, A.; Verney, A.; Hellard, P.

2017-02-01

Robust tracking is a crucial step in automatic swimmer evaluation from video sequences. We designed a robust swimmer tracking system using a new multi-related-targets approach. The main idea is to consider the swimmer as a bloc of connected subtargets that advance at the same speed. If one of the subtargets is partially or totally occluded, it can be localized by knowing the position of the others. In this paper, we first introduce the two-dimensional direct linear transformation technique that we used to calibrate the videos. Then, we present the classical tracking approach based on dynamic fusion. Next, we highlight the main contribution of our work, which is the multi-related-targets tracking approach. This approach, the classical head-only approach and the ground truth are then compared, through testing on a database of high-level swimmers in training, national and international competitions (French National Championships, Limoges 2015, and World Championships, Kazan 2015). Tracking percentage and the accuracy of the instantaneous speed are evaluated and the findings show that our new appraoach is significantly more accurate than the classical approach.

Oxidative damage of DNA in subjects occupationally exposed to lead.

Science.gov (United States)

Pawlas, Natalia; Olewińska, Elżbieta; Markiewicz-Górka, Iwona; Kozłowska, Agnieszka; Januszewska, Lidia; Lundh, Thomas; Januszewska, Ewa; Pawlas, Krystyna

2017-09-01

Exposure to lead (Pb) in environmental and occupational settings continues to be a serious public health problem and may pose an elevated risk of genetic damage. The aim of this study was to assess the level of oxidative stress and DNA damage in subjects occupationally exposed to lead. We studied a population of 78 male workers exposed to lead in a lead and zinc smelter and battery recycling plant and 38 men from a control group. Blood lead levels were detected by graphite furnace atomic absorption spectrophotometry and plasma lead levels by inductively coupled plasma-mass spectrometry. The following assays were performed to assess the DNA damage and oxidative stress: comet assay, determination of 8-hydroxy-2'-deoxyguanosine (8-OHdG), lipid peroxidation and total antioxidant status (TAS). The mean concentration of lead in the blood of the exposed group was 392 ± 103 μg/L and was significantly higher than in the control group (30.3 ± 29.4 μg/L, p lead exposure [lead in blood, lead in plasma, zinc protoporphyrin (ZPP)] and urine concentration of 8-OHdG. The level of oxidative damage of DNA was positively correlated with the level of lipid peroxidation (TBARS) and negatively with total anti-oxidative status (TAS). Our study suggests that occupational exposure causes an increase in oxidative damage to DNA, even in subjects with relatively short length of service (average length of about 10 years). 8-OHdG concentration in the urine proved to be a sensitive and non-invasive marker of lead induced genotoxic damage.

Effects of air pollution on landscape and land-use around Norwegian aluminium smelters

Energy Technology Data Exchange (ETDEWEB)

Gilbert, O L

1975-01-01

Investigations around three aluminium smelters in Norway revealed that air pollution emanating from the works was affecting landscape and land-use for a distance of several kilometers. A zonal pattern of damage to the total flora is described in sufficient detail to act as a field guide for the recognition of this type of fume damage. Reasons for believing the observed effects to be due to fluorides are given and the visual and ecological consequences discussed. It is important that when expansion of the aluminium producing industry occurs this is undertaken in full realization of the possible consequences.

Safeguarding Self-Governance: A Grounded Theory of Older Patients’ Pattern of Behavior in Relation to their Relatives in Fast-track Programs

DEFF Research Database (Denmark)

Berthelsen, Connie B.; Frederiksen, Kirsten; Lindhardt Damsgaard, Tove

2014-01-01

Abstract The aim of this study was to generate a grounded theory of older patients’ pattern of behavior in relation to their relatives’ involvement in fast-track programs during total joint replacement. Sixteen patients were recruited in orthopedic wards. Data collection included 11 interviews......, shielding, distancing, and masking. Keywords: Fast-track program, grounded theory, older patients, relatives, total joint replacement.......-governance emerged in the analysis as the core category of our theory and pattern of behavior of the older patients in relation to their relatives. The older patients’ main concern was to complete the fast-track program while maintaining autonomy, which they resolved through four strategies of actions: embracing...

Comparison of ETF´s performance related to the tracking error

Directory of Open Access Journals (Sweden)

Michaela Dorocáková

2017-12-01

Full Text Available With the development of financial markets, there is also immediate expansion of fund industry, which is a representative issue of collective investment. The purpose of index funds is to replicate returns and risk of underling index to the largest possible extent, with tracking error being one of the most monitored performance indicator of these passively managed funds. The aim of this paper is to describe several perspectives concerning indexing, index funds and exchange-traded funds, to explain the issue of tracking error with its examination and subsequent comparison of such funds provided by leading investment management companies with regard to different methods used for its evaluation. Our research shows that the decisive factor for occurrence of copy deviation is fund size and fund´s stock consolidation. In addition, performance differences between exchange-traded fund and its benchmark tend to show the signs of seasonality in the sense of increasing in the last months of a year.

78 FR 33409 - Proposed Information Collection Request; Comment Request; See Item Specific ICR Titles Provided...

Science.gov (United States)

2013-06-04

... Production (40 CFR Part 60, Subpart M), Primary Copper Smelters (40 CFR Part 60, Subpart P), Primary Zinc... bronze production facilities, primary copper smelters, primary zinc smelters, primary lead smelters... ID Number: EPA-HQ-OECA-2013-0314; Title: NSPS for Phosphate Rock Plants (40 CFR Part 60, Subpart NN...

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...... and knowledge building as related to relational leading. The practices developed in the thesis research demonstrate that it is possible to create organizational learning and development through collaborative, dialogic practices in groups and teams, for instance combined with the use of roleplaying. In the work...... 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...

AS SPECIATION AND EFFECTS OF PH AND PHOSPHATE ON THE MOBILIZATION OF AS IN SOILS FROM A LEAD SMELTING SITE. PUBLISHED IN ADVANCED PHOTON SOURCE ACTIVITY REPORT 2003.

Science.gov (United States)

Arsenic in soils from the Asarco lead smelter in East Helena, Montana was characterized by X-ray absorption spectroscopy (XAS). Arsenic oxidation state and mineralogy were analyzed as a function of depth and surface distribution using bulk and microprobe XAS. These results were c...

The impact of aluminium smelter shut-down on the concentration of fluoride in vegetation and soils

International Nuclear Information System (INIS)

Brougham, Kate M.; Roberts, Stephen R.; Davison, Alan W.; Port, Gordon R.

2013-01-01

Although a great deal is known about the deposition of fluoride on vegetation, and the hazards associated with uptake by grazing herbivores, little is known about what happens to the concentration of fluoride in vegetation and soil at polluted sites once deposition ceases. The closure of Anglesey Aluminium Metals Ltd smelter, in September 2009, provided a unique opportunity to study fluoride loading once deposition stopped. Fluoride was monitored in plants and soil within 1 km of the former emission source. Fluoride concentrations in a range of plant material had decreased to background levels of 10 mg F kg −1 after 36 weeks. Concentrations of fluoride in mineral-rich soils decreased steadily demonstrating their limited potential to act as contaminating sources of fluoride for forage uptake. There were significant differences in the rate of decline of fluoride concentrations between plant species. -- Highlights: •The impact of aluminium smelter closure on fluoride concentrations was investigated. •Concentrations in forage decreased rapidly to safe levels for livestock grazing. •The concentrations in some species declined to background levels within a year. •Significant interspecies differences in fluoride decline are described. •Mineral-rich soils have limited potential as contaminating sources for forage. -- Fluoride is hazardous to grazing herbivores, but when deposition stops, F-levels in plants and soil fall rapidly, some returning to background concentrations within a year

Modeling and evaluation of urban pollution events of atmospheric heavy metals from a large Cu-smelter.

Science.gov (United States)

Chen, Bing; Stein, Ariel F; Castell, Nuria; Gonzalez-Castanedo, Yolanda; Sanchez de la Campa, A M; de la Rosa, J D

2016-01-01

Metal smelting and processing are highly polluting activities that have a strong influence on the levels of heavy metals in air, soil, and crops. We employ an atmospheric transport and dispersion model to predict the pollution levels originated from the second largest Cu-smelter in Europe. The model predicts that the concentrations of copper (Cu), zinc (Zn), and arsenic (As) in an urban area close to the Cu-smelter can reach 170, 70, and 30 ng m−3, respectively. The model captures all the observed urban pollution events, but the magnitude of the elemental concentrations is predicted to be lower than that of the observed values; ~300, ~500, and ~100 ng m−3 for Cu, Zn, and As, respectively. The comparison between model and observations showed an average correlation coefficient of 0.62 ± 0.13. The simulation shows that the transport of heavy metals reaches a peak in the afternoon over the urban area. The under-prediction in the peak is explained by the simulated stronger winds compared with monitoring data. The stronger simulated winds enhance the transport and dispersion of heavy metals to the regional area, diminishing the impact of pollution events in the urban area. This model, driven by high resolution meteorology (2 km in horizontal), predicts the hourly-interval evolutions of atmospheric heavy metal pollutions in the close by urban area of industrial hotspot.

Human dietary exposure and levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DL-PCBs) and non-dioxin-like polychlorinated biphenyls (NDL-PCBs) in free-range eggs close to a secondary aluminum smelter, Northern Italy

International Nuclear Information System (INIS)

Squadrone, S.; Brizio, P.; Nespoli, R.; Stella, C.; Abete, M.C.

2015-01-01

PCDD/Fs and PCBs are environmentally persistent substances that have been associated with adverse effects on human health. Contamination of soils, animal feed and pastures leads to their bioaccumulation of in food products of animal origin, which are considered the major source of intake of these contaminants in humans. We analyzed eggs from free-range hens, sampled from small farms, located within a distance of 4.5 km from a secondary aluminum smelter in Northern Italy. The concentrations of PCDD/Fs, DL-PCBs and NDL-PCBs were higher in eggs from locations close to the plant, and strongly exceeded the limits set by EU Regulation 1259/2011 (2.5 pg WHO TEQ fat g"−"1 for PCDD/Fs, 5.0 pg WHO TEQ g"−"1 for PCDD/Fs and DL-PCBs L, 40 ng g"−"1 for NDL-PCBs). Consuming contaminated eggs may pose a risk for human health, especially for children (≤9 years) and infants (≤3 years), due to the 2-fold excess of the current exposure limits. - Highlights: • We analyzed free-range eggs from farms close to a secondary aluminum smelter (ALS). • Concentrations of dioxins and PCBs strongly exceeded the limit set by EU Regulation. • Concentrations decrease at increasing distances from the plant. • Consuming contaminated eggs may pose a health risk for humans. - Concentrations of PCDD/Fs, DL-PCBs and NDL-PCBs are of concern in free-range eggs close to a secondary aluminum smelter.

Relating Tropical Cyclone Track Forecast Error Distributions with Measurements of Forecast Uncertainty

Science.gov (United States)

2016-03-01

CYCLONE TRACK FORECAST ERROR DISTRIBUTIONS WITH MEASUREMENTS OF FORECAST UNCERTAINTY by Nicholas M. Chisler March 2016 Thesis Advisor...March 2016 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE RELATING TROPICAL CYCLONE TRACK FORECAST ERROR DISTRIBUTIONS...WITH MEASUREMENTS OF FORECAST UNCERTAINTY 5. FUNDING NUMBERS 6. AUTHOR(S) Nicholas M. Chisler 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES

The environmental rules of economic development: Governing air pollution from smelters in Chuquicamata and La Oroya

OpenAIRE

Orihuela, José Carlos

2015-01-01

Why and how do societies transform the environmental rules of economic development, or fail to do so? This article compares the experiences of Chile and Peru in the regulation of smelting activities between 1990 and 2010. Air pollution from smelters in  Chuquicamata  and  La Oroya, each emblematic of the two countries’ mining industries, did not give rise to nationally destabilising protest. Nevertheless, despite the absence of pressing discontent with pollution, the environmental rules for m...

Observations on the geometries of etched fission and alpha-recoil tracks with reference to models of track revelation in minerals

International Nuclear Information System (INIS)

Jonckheere, R.; Enkelmann, E.; Stuebner, K.

2005-01-01

The kinetic and atomistic theories of crystal growth and dissolution are used to interpret the shapes and orientations of fission-track, recoil-track and dislocation etch pits in tri-octahedral phlogopite and di-octahedral muscovite. An atomistic approach combined with symmetry considerations lead to the identification of the periodic bond chains that determine the etch pit morphologies and relative etch rates at a chemical level: O-Mg-O in phlogopite, O-Mg-O-Fe in biotite and O-Al-O in muscovite. Using first-order estimates of the bond strengths, it is possible to account for the relative track etch rates in these minerals. The reported, sometimes simultaneous, occurrence of triangular, polygonal and hexagonal etch pit contours in phlogopite, some of which violate the crystal symmetry, suggests that the cohesion of the phlogopite lattice is lost over a much larger radius than that of the track core around the trajectories of particles for which the energy loss exceeds a threshold value. This is interpreted as an indication of pronounced sublattice and anisotropic effects during track registration

The lead and lead-acid battery industries during 2002 and 2007 in China

Energy Technology Data Exchange (ETDEWEB)

Chen, H.Y.; Li, A.J.; Finlow, D.E. [Key Lab of Electrochemical Technology on Energy Storage and Power Generation in Guangdong Universities, School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)

2009-06-01

In the past 15 years, the center of the international lead market has shifted to China. China has become the largest producer of raw and refined lead, plus the largest consumer. This paper reviews the status of the lead and lead-acid battery industries in China, including lead mining, lead refining, secondary lead production, the lead-acid battery industry, new opportunities for lead-acid batteries, and the environmental problems associated with lead and lead-acid batteries. The output of raw and refined lead has increased annually in China, and now accounts for more than 30% of the world total. As a result of a change in the Chinese government's policy regarding the export of lead, plus an increase in the price of lead, the profits of Chinese lead manufacturers were significantly reduced, the trade deficit of the Chinese lead industry increased, the operating rates of lead smelter enterprises greatly reduced, and some small enterprises were forced to shut down. At the present time, an increasing number of enterprises have begun to produce secondary lead, and the scale of production has expanded from tens of tons to tens of thousands of tons. In 2006, the output of secondary lead in China reached 700,000 tons, but outdated technology and equipment limited development of the secondary lead industry. Because of serious pollution problems, raw material shortages, and fierce price competition in the battery market, changes in the development of the lead-acid battery industry have been dramatic; approximately one thousand medium-sized and small lead-acid battery producers have been closed in the past 3 years. The output of large lead-acid battery enterprises has not been reduced, however, as a result of their manufacturing technology and equipment being comparable to those in other advanced industrial countries. In China, the flourishing development of electric bicycles, electric tricycles, and photovoltaic energy systems should provide ongoing opportunities for

The lead and lead-acid battery industries during 2002 and 2007 in China

International Nuclear Information System (INIS)

Chen, H.Y.; Li, A.J.; Finlow, D.E.

2009-01-01

In the past 15 years, the center of the international lead market has shifted to China. China has become the largest producer of raw and refined lead, plus the largest consumer. This paper reviews the status of the lead and lead-acid battery industries in China, including lead mining, lead refining, secondary lead production, the lead-acid battery industry, new opportunities for lead-acid batteries, and the environmental problems associated with lead and lead-acid batteries. The output of raw and refined lead has increased annually in China, and now accounts for more than 30% of the world total. As a result of a change in the Chinese government's policy regarding the export of lead, plus an increase in the price of lead, the profits of Chinese lead manufacturers were significantly reduced, the trade deficit of the Chinese lead industry increased, the operating rates of lead smelter enterprises greatly reduced, and some small enterprises were forced to shut down. At the present time, an increasing number of enterprises have begun to produce secondary lead, and the scale of production has expanded from tens of tons to tens of thousands of tons. In 2006, the output of secondary lead in China reached 700,000 tons, but outdated technology and equipment limited development of the secondary lead industry. Because of serious pollution problems, raw material shortages, and fierce price competition in the battery market, changes in the development of the lead-acid battery industry have been dramatic; approximately one thousand medium-sized and small lead-acid battery producers have been closed in the past 3 years. The output of large lead-acid battery enterprises has not been reduced, however, as a result of their manufacturing technology and equipment being comparable to those in other advanced industrial countries. In China, the flourishing development of electric bicycles, electric tricycles, and photovoltaic energy systems should provide ongoing opportunities for the

40 CFR Appendix Xi to Part 266 - Lead-Bearing Materials That May be Processed in Exempt Lead Smelters

Science.gov (United States)

2010-07-01

... PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR THE MANAGEMENT OF SPECIFIC HAZARDOUS... pallets Water treatment sludges, filter cakes, residues, and solids Emission control dusts, sludges, filter cakes, residues, and solids from lead-associated industries (e.g., K069 and D008 wastes) Spent...

Differences in antimony and arsenic releases from lead smelter fly ash in soils

Czech Academy of Sciences Publication Activity Database

Ettler, V.; Mihaljevič, M.; Šebek, O.; Valigurova, R.; Klementová, Mariana

2012-01-01

Roč. 72, Supp. 4 (2012), s. 15-22 ISSN 0009-2819 Institutional research plan: CEZ:AV0Z40320502 Keywords : Antimony * Arsenic * Lead smelting * Fly ash * Soil * Mobility Subject RIV: CA - Inorganic Chemistry Impact factor: 1.351, year: 2012

Toxicity of smelter slag-contaminated sediments from Upper Lake Roosevelt and associated metals to early life stage White Sturgeon (Acipenser transmontanus Richardson, 1836)

Science.gov (United States)

Little, E.E.; Calfee, R.D.; Linder, G.

2014-01-01

The toxicity of five smelter slag-contaminated sediments from the upper Columbia River and metals associated with those slags (cadmium, copper, zinc) was evaluated in 96-h exposures of White Sturgeon (Acipenser transmontanus Richardson, 1836) at 8 and 30 days post-hatch. Leachates prepared from slag-contaminated sediments were evaluated for toxicity. Leachates yielded a maximum aqueous copper concentration of 11.8 μg L−1 observed in sediment collected at Dead Man's Eddy (DME), the sampling site nearest the smelter. All leachates were nonlethal to sturgeon that were 8 day post-hatch (dph), but leachates from three of the five sediments were toxic to fish that were 30 dph, suggesting that the latter life stage is highly vulnerable to metals exposure. Fish maintained consistent and prolonged contact with sediments and did not avoid contaminated sediments when provided a choice between contaminated and uncontaminated sediments. White Sturgeon also failed to avoid aqueous copper (1.5–20 μg L−1). In water-only 96-h exposures of 35 dph sturgeon with the three metals, similar toxicity was observed during exposure to water spiked with copper alone and in combination with cadmium and zinc. Cadmium ranging from 3.2 to 41 μg L−1 or zinc ranging from 21 to 275 μg L−1 was not lethal, but induced adverse behavioral changes including a loss of equilibrium. These results suggest that metals associated with smelter slags may pose an increased exposure risk to early life stage sturgeon if fish occupy areas contaminated by slags.

Studying of metals distribution in the Pinus Sylvestris bark and needles in a zone of influence the gradient polluted air stream from Cu-smelter

International Nuclear Information System (INIS)

Aminov, P.G.; Lonshchakova, G.F.

2008-01-01

In the paper the features of accumulation for heavy metals by pine needles and bark in the gradient dispersion area of technogenic elements and using of the bark as the bioindicator to establish influencing zones of smelter on environment are represented

Bio-processing of copper from combined smelter dust and flotation concentrate: a comparative study on the stirred tank and airlift reactors.

Science.gov (United States)

Vakylabad, Ali Behrad; Schaffie, Mahin; Ranjbar, Mohammad; Manafi, Zahra; Darezereshki, Esmaeel

2012-11-30

To scrutinize the influence of the design and type of the bioreactors on the bioleaching efficiency, the bioleaching were evaluated in a batch airlift and a batch stirred tank bioreactors with mixed mesophilic and mixed moderately thermophilic bacteria. According to the results, maximum copper recoveries were achieved using the cultures in the stirred tank bioreactors. It is worth noting that the main phase of the flotation concentrate was chalcopyrite (as a primary sulphide), but the smelter dust mainly contained secondary copper sulphides such as Cu(2)S, CuS, and Cu(5)FeS(4).Under optimum conditions, copper dissolution from the combined flotation concentrate and smelter dust (as an environmental hazard) reached 94.50% in the STR, and 88.02% in the airlift reactor with moderately thermophilic, after 23 days. Also, copper extractions calculated for the bioleaching using mesophilic bacteria were 48.73% and 37.19% in the STR (stirred tank reactor) and the airlift bioreactor, respectively. In addition, the SEM/EDS, XRD, chemical, and mineralogical analyses and studies confirmed the above results. Copyright © 2012 Elsevier B.V. All rights reserved.

Maintaining Unity - relatives in older patients' fast-track treatment programmes. A grounded theory study.

Science.gov (United States)

Berthelsen, Connie Bøttcher; Lindhardt, Tove; Frederiksen, Kirsten

2014-12-01

To generate a substantive grounded theory of relatives' pattern of behaviour in older patients' fast-track treatment programmes during total hip or knee replacement. Fast-track treatment programmes are designed to make total hip and knee replacements more efficient through recovery improvements. The support of relatives during older patients' trajectory is important. However, knowledge is needed on the relatives' pattern of behaviour to strengthen their involvement in fast-track treatment programmes. We used a Glaserian grounded theory approach based on a systematic generation of theory from data to explain the latent pattern of behaviour of relatives. Data were collected from 2010-2011 in orthopaedic wards at two Danish university hospitals and consisted of 14 non-participant observations, 14 postobservational interviews and five interviews. Seven relatives of patients over 70 years of age participated. The constant comparative method was the guiding principle for simultaneous data collection, data analysis and coding, while theoretically sampling and writing memos. Maintaining Unity emerged as the relatives' pattern of behaviour through which they resolved their main concern: preventing the patients from feeling alone. The relatives resolved their main concern through three interchangeable behavioural modes: Protecting Mode, by providing loving and respectful support; Substituting Mode, with practical and cognitive support; and an Adapting Mode, by trying to fit in with the patients' and health professionals' requirements. The substantive theory of Maintaining Unity offers knowledge of relatives' strong desire to provide compassionate and loving support for the older patients during fast-track treatment programmes. © 2014 John Wiley & Sons Ltd.

A comparison of tracking with visual and kinesthetic-tactual displays

Science.gov (United States)

Jagacinski, R. J.; Flach, J. M.; Gilson, R. D.

1981-01-01

Recent research on manual tracking with a kinesthetic-tactual (KT) display suggests that under appropriate conditions it may be an effective means of providing visual workload relief. In order to better understand how KT tracking differs from visual tracking, both a critical tracking task and stationary single-axis tracking tasks were conducted with and without velocity quickening. On the critical tracking task, the visual displays were superior; however, the KT quickened display was approximately equal to the visual unquickened display. Mean squared error scores in the stationary tracking tasks for the visual and KT displays were approximately equal in the quickened conditions, and the describing functions were very similar. In the unquickened conditions, the visual display was superior. Subjects using the unquickened KT display exhibited a low frequency lead-lag that may be related to sensory adaptation.

Geochemical position of Pb, Zn and Cd in soils near the Olkusz mine/smelter, South Poland: effects of land use, type of contamination and distance from pollution source.

Science.gov (United States)

Chrastný, Vladislav; Vaněk, Aleš; Teper, Leslaw; Cabala, Jerzy; Procházka, Jan; Pechar, Libor; Drahota, Petr; Penížek, Vít; Komárek, Michael; Novák, Martin

2012-04-01

The soils adjacent to an area of historical mining, ore processing and smelting activities reflects the historical background and a mixing of recent contamination sources. The main anthropogenic sources of metals can be connected with historical and recent mine wastes, direct atmospheric deposition from mining and smelting processes and dust particles originating from open tailings ponds. Contaminated agriculture and forest soil samples with mining and smelting related pollutants were collected at different distances from the source of emission in the Pb-Zn-Ag mining area near Olkusz, Upper Silesia to (a) compare the chemical speciation of metals in agriculture and forest soils situated at the same distance from the point source of pollution (paired sampling design), (b) to evaluate the relationship between the distance from the polluter and the retention of the metals in the soil, (c) to describe mineralogy transformation of anthropogenic soil particles in the soils, and (d) to assess the effect of deposited fly ash vs. dumped mining/smelting waste on the mobility and bioavailability of metals in the soil. Forest soils are much more affected with smelting processes than agriculture soils. However, agriculture soils suffer from the downward metal migration more than the forest soils. The maximum concentrations of Pb, Zn, and Cd were detected in a forest soil profile near the smelter and reached about 25 g kg(- 1), 20 g kg(- 1) and 200 mg kg(- 1) for Pb, Zn and Cd, respectively. The metal pollutants from smelting processes are less stable under slightly alkaline soil pH then acidic due to the metal carbonates precipitation. Metal mobility ranges in the studied forest soils are as follows: Pb > Zn ≈ Cd for relatively circum-neutral soil pH (near the smelter), Cd > Zn > Pb for acidic soils (further from the smelter). Under relatively comparable pH conditions, the main soil properties influencing metal migration are total organic carbon and cation exchange

Time evolution of hadronization and grey tracks in DIS off nuclei

International Nuclear Information System (INIS)

Ciofi degli Atti, C.; Kopeliovich, B.Z.

2005-01-01

The analysis of the grey tracks produced in deep inelastic scattering (DIS) off nuclei provides important information on the space-time development of hadronization in nuclear medium. This method is complementary to the measurement of nuclear attenuation of leading inclusive hadrons. While the latter is focused on the hadronization dynamics for the quite rare process of leading hadrons production, the former covers the main bulk of inelastic events, and its Q 2 dependence is a very sensitive tool to discriminate between different models of hadronization. Employing the model of perturbative hadronization developed earlier, we calculate the Q 2 and x Bj dependences of the number of collisions and relate it to the mean number of grey tracks, using an empirical relation obtained from the analysis of data from the Fermilab E665 experiment on DIS of muons off the Xe nucleus. We found the number of grey tracks to rise steeply with Q 2 in good agreement with the experimental data

Trace Element Concentrations in Tree Leaves and Lichen Collected Along a Metal Pollution Gradient Near Olkusz (Southern Poland).

Science.gov (United States)

Zakrzewska, Marta; Klimek, Beata

2018-02-01

The aim of the study was to assess the metal pollution in the vicinity of the Bukowno smelter near Olkusz in southern Poland. Birch and oak leaves, pine needles and a lichen Hypogymnia physodes, overgrowing pine bark were collected at stands at different distances from the smelter and analysed for cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) content. Concentrations of metals in the lichen were usually higher than in the tree leaves/needles and decreased with distance from the smelter, apart from the Cu content. The strongest correlation was noticed between Cd and Pb concentrations, which indicates a common pollution source (the smelter). Our results show that birch leaves can be potentially useful as a bioindicator of Zn air pollution since this species was shown to accumulate high amounts of zinc, related to environmental pollution with that metal, in their leaves.

Modifications of the sympathetic skin response in workers chronically exposed to lead

Directory of Open Access Journals (Sweden)

D.B. Nora

2007-01-01

Full Text Available The long-term effects of low-level lead intoxication are not known. The sympathetic skin response (SSR was evaluated in a group of 60 former workers of a primary lead smelter, located in Santo Amaro, BA, Brazil. The individuals participating in the study were submitted to a clinical-epidemiological evaluation including questions related to potential risk factors for intoxication, complaints related to peripheral nervous system (PNS involvement, neurological clinical examination, and also to electromyography and nerve conduction studies and SSR evaluation. The sample consisted of 57 men and 3 women aged 34 to 69 years (mean ± SD: 46.8 ± 6.9. The neurophysiologic evaluation showed the presence of lumbosacral radiculopathy in one of the individuals (1.7%, axonal sensorimotor polyneuropathy in 2 (3.3%, and carpal tunnel syndrome in 6 (10%. SSR was abnormal or absent in 12 cases, representing 20% of the sample. More than half of the subjects (53.3% reported a history of acute abdominal pain requiring hospitalization during the period of work at the plant. A history of acute palsy of radial and peroneal nerves was reported by about 16.7 and 8.3% of the individuals, respectively. Mean SSR amplitude did not differ significantly between patients presenting or not the various characteristics in the current neurological situation, except for diaphoresis. The results suggest that chronic lead intoxication induces PNS damage, particularly affecting unmyelinated small fibers. Further systematic study is needed to more precisely define the role of lead in inducing PNS injury.

The UIC 406 capacity method used on single track sections

DEFF Research Database (Denmark)

Landex, Alex; Kaas, Anders H.; Jacobsen, Erik M.

2007-01-01

This paper describes the relatively new UIC 406 capacity method which is an easy and effective way of calculating capacity consumption on railway lines. However, it is possible to expound the method in different ways which can lead to different capacity consumptions. This paper describes the UIC...... 406 method for single track lines and how it is expounded in Denmark. Many capacity analyses using the UIC 406 capacity method for double track lines have been carried out and presented internationally but only few capacity analyses using the UIC 406 capacity method on single track lines have been...... presented. Therefore, the differences between capacity analysis for double track lines and single track lines are discussed in the beginning of this paper. Many of the principles of the UIC 406 capacity analyses on double track lines can be used on single track lines – at least when more than one train...

Arsenic and cadmium exposure in children living near a smelter complex in San Luis Potosi, Mexico

Energy Technology Data Exchange (ETDEWEB)

Diaz-Barriga, F.; Santos, M.A.; Mejia, J.J.; Batres, L.; Yanez, L.; Carrizales, L.; Vera, E.; del Razo, L.M.; Cebrian, M.E. (Universidad Autonoma de San Luis Potosi (Mexico))

1993-08-01

The main purpose of this study was to assess environmental contamination by arsenic and cadmium in a smelter community (San Luis Potosi City, Mexico) and its possible contribution to an increased body burden of these elements in children. Arsenic and cadmium were found in the environment (air, soil, and household dust, and tap water) as well as in the urine and hair from children. The study was undertaken in three zones: Morales, an urban area close to the smelter complex; Graciano, an urban area 7 km away from the complex; and Mexquitic, a small rural town 25 km away. The environmental study showed that Morales is the most contaminated of the zones studied. The range of arsenic levels in soil (117-1396 ppm), dust (515-2625 ppm), and air (0.13-1.45 micrograms/m3) in the exposed area (Morales) was higher than those in the control areas. Cadmium concentrations were also higher in Morales. Estimates of the arsenic ingestion rate in Morales (1.0-19.8 micrograms/kg/day) were equal to or higher than the reference dose of 1 microgram/kg/day calculated by the Environmental Protection Agency. The range of arsenic levels in urine (69-594 micrograms/g creatinine) and hair (1.4-57.3 micrograms/g) and that of cadmium in hair (0.25-3.5 micrograms/g) indicated that environmental exposure has resulted in an increased body burden of these elements in children, suggesting that children living in Morales are at high risk of suffering adverse health effects if exposure continues.

Micro-spatial variation of soil metal pollution and plant recruitment near a copper smelter in Central Chile

International Nuclear Information System (INIS)

Ginocchio, Rosanna; Carvallo, Gaston; Toro, Ignacia; Bustamante, Elena; Silva, Yasna; Sepulveda, Nancy

2004-01-01

Soil chemical changes produced by metal smelters have mainly been studied on a large scale. In terms of plant survival, determination of small scale variability may be more important because less toxic microhabitats may represent safe sites for successful recruitment and thus for plant survival. Three dominant microhabitats (open spaces and areas below the canopy of Sphaeralcea obtusiloba and Baccharis linearis shrubs) were defined in a heavily polluted area near a copper smelter and characterised in terms of microclimate, general soil chemistry, total and extractable metal concentrations in the soil profile (A 0 horizon, 0-5 and 15-20 cm depth), and seedling densities. Results indicated a strong variability in microclimate and soil chemistry not only in the soil profile but also among microhabitats. Air/soil temperatures, radiation and wind speed were much lower under the canopy of shrubs, particularly during the plant growth season. Soil acidification was detected on top layers (0-5 cm depth) of all microhabitats while higher concentrations of N, Cu and Cd were detected on litter and top soil layers below shrubs when compared to open spaces; however, high organic matter content below shrubs decreased bioavailability of metals. Plant recruitment was concentrated under shrub canopies; this may be explained as a result of the nursery effect exerted by shrubs in terms of providing a more favourable microclimate, along with better soil conditions in terms of macronutrients and metal bioavailability. - Metal availability was different under shrub canopies than in open spaces

Bitumen stabilized ballast: a potential solution for railway track-bed

OpenAIRE

D'Angelo, Giacomo; Thom, Nicholas; Lo Presti, Davide

2016-01-01

Railway ballast degradation under dynamic loads progressively leads to loss of mechanical performance and geometry of the track, so that maintenance interventions are frequently needed. In order to systematically avoid this issue, recently solutions have been proposed to reinforce track-bed by using polyurethane and/or resins as well as asphalt layers among others. Nonetheless, their main limitations are related to the high initial cost and low productivity.\\ud To cope with these limitations,...

A reengineering success story: process improvement in emergency department x-ray cycle time, leading to breakthrough performance in the ED ambulatory care (Fast Track) process.

Science.gov (United States)

Espinosa, J A; Treiber, P M; Kosnik, L

1997-01-01

This article describes the journey of a multidisciplinary reengineering team, which worked to reduce a critical, high-leverage process in an emergency department setting. The process selected was emergency department radiology services. This process was selected on a rational basis. The team knew tht 60 percent of our emergency department patients were truly ambulatory, and that most could be seen in a "fast track" process as part of our emergency department's core mission. However, we knew from customer satisfaction data, that patients would like to be "in and out" of emergency department Fast Track in less than an hour. Over half of our Fast Track patients require x-rays. For most, this was their sole reason for seeking emergency care. Our state, at the start of the project, included an average x-ray cycle time of over 60 minutes. The associated Fast-Track cycle time was over 90 minutes median. It was clear to the emergency department leadership, as well as to members of the Fast-Track management team, that a cycle time of 30 minutes or less for x-ray service was needed as a necessary condition to an hour or less Fast Track cycle time. It was also felt that a more rapid x-ray cycle time would allow for more rapid turn over of ED rooms, leading to a virtual greater capacity to the ED. It was hoped that this would lead to a reduction in the time from arrival to treatment by the emergency physician for all patients.

Effects of dietary lead exposure on vitamin levels in great tit nestlings – An experimental manipulation

International Nuclear Information System (INIS)

Ruiz, Sandra; Espín, Silvia; Rainio, Miia; Ruuskanen, Suvi; Salminen, Juha-Pekka; Lilley, Thomas M.; Eeva, Tapio

2016-01-01

Exposure to metal pollution negatively affects animal physiology, including nutrient metabolism, but in the wild an effect can seldom be attributed to a single metal. Moreover, little is known about how the metabolism of vitamins, essential micronutrients for developing juveniles, is affected by toxic metals. Therefore we experimentally investigated the effects of lead (Pb), a widespread toxic metal, on four fat-soluble vitamins A (total and retinol), D 3 , E (total and α-tocopherol) and K and carotenoids (lutein, zeaxanthin and unidentified) in great tit (Parus major) nestlings. In addition to a control group where no Pb was provided, two Pb-dosed groups were compared to a metal exposed group in the vicinity of a Ni–Cu smelter. We examined whether Pb treatment affects vitamin homeostasis and how the response of Pb-treated birds relates to that of a population under industrial exposure of Pb and other metals. For this purpose, vitamin and carotenoid levels were quantified with UPLC-MS from plasma of 7 days-old nestlings. All metal exposed groups showed increased vitamin A and retinol levels. However, vitamin levels were not directly associated with fecal Pb levels, with the exception of retinol, which was positively correlated with fecal Pb. Alpha-tocopherol, lutein and zeaxanthin levels were positively associated with body mass and wing growth rate. To conclude, Pb exposure increased plasma vitamin A and retinol levels while the levels of other vitamins and carotenoids rather reflected secondary pollution effects via differences in habitat and diet quality at the smelter site. Our findings suggest Pb exposed nestlings may allocate the vitamins needed for growth and development to fight the physiological stress thus compromising their fitness. - Highlights: • Pb effects on vitamins A, D 3 , E and K in wild great tit nestlings were investigated. • Four treatment groups were established: Control, Low-Pb, High-Pb and Smelter. • Pb concentrations measured in

Comparison of two indices of exposure to polycyclic aromatic hydrocarbons in a retrospective aluminium smelter cohort

Energy Technology Data Exchange (ETDEWEB)

Friesen, M.C.; Demers, P.A.; Spinelli, J.J.; Lorenzi, M.F.; Le, N.D. [University of British Columbia, Vancouver, BC (Canada)

2007-04-15

The association between coal tar-derived substances, a complex mixture of polycyclic aromatic hydrocarbons, and cancer is well established. However, the specific aetiological agents are unknown. The paper compares the dos-response relationships for two common measures of coal tar-derived substances, benzene-soluble material (BSM) and benzo (a) pyrene (BaP), and to evaluate which among these is more strongly related to the health outcomes. The study population consisted of 6423 men with {gt} 3 years of work experience at an aluminium smelter (1954 - 97). Three health outcomes identified from national mortality and cancer databases were evaluated: incidence of bladder cancer (n = 90), incidence of lung cancer (n = 147) and mortality due to acute myocardial infarction (AMI, n = 184). The shape, magnitude and precision of the dose - response relationships and cumulative exposure levels for BSM and BaP were evaluated. Two model structures were assessed, where 1n (relative risk) increased with cumulative exposure (log-linear model) or with log- transformed cumulative exposure (log-log model). It was found that BaP and BSM were both strongly associated with bladder and lung cancer and modestly associated with AMI. Similar conclusions regarding the associations could be made regardless of the exposure metric.

Application of nuclear track detectors for radon related measurments

International Nuclear Information System (INIS)

Abu-Jarad, F.A.

1988-01-01

The application of nuclear track detectors for radon related measurements is discussed. The ''Can Technique'', used for measuring radon emanation from building materials, walls and soil; the ''Working Level Monitor'', used for measuring short period working levels of radon daughters in houses; and ''Passive Radon Dosimeters'', used to measure radon levels in houses for long term (few months) periods are described. Application of nuclear track detectors for measuring the radon daughters plate-out on the surface of mixing fan blades and walls are discussed. The uranium content of some wall papers was found to be 6 ppm. The variation of radon progeny concentration in the same room was measured and supported by another study through Gas Chromatograph measurements. The independence of radon concentration on room level in high-rise buildings was established. The effect of sub-floor radon emanation on radon concentration in houses is dependent on whether there is sub-floor ventilation or not. (author)

Tracks, spurs, blobs and delta-rays

International Nuclear Information System (INIS)

Magee, J.L.; Chatterjee, A.

1983-01-01

The track of a high-energy particle is the collection of all transient species created by the particle in the total degradation of its energy. Visible electron tracks are called delta rays. A microscopic description of the track with all its knocked-out electrons leads to spurs, blobs, and short tracks. Energy deposition criteria for these three track entities are 6 to 100 eV, 100 to 500 eV, and 500 eV to 5 keV, respectively

Relations between Scots pine needle element concentrations and decreased needle longevity along pollution gradients

International Nuclear Information System (INIS)

Lamppu, Jukka; Huttunen, Satu

2003-01-01

Deceased needle longevity was related to increased heavy metal concentrations. - Scots pine (Pinus sylvestris L.) shoots were sampled along transects near one urban pollution source and two smelters. Needle Mg, P and K concentrations decreased from the second to the fourth age class linearly with needle survival along the urban pollution gradient. Still, over 80% of the average concentration of these nutrients remained in the fourth needle age class. Decreased needle longevity was closely related to the increased heavy metal concentrations near the smelters. Near the urban pollution source, it was related to the increased annual needle mass and the increased needle nutrient concentrations. Decreased Mn accumulation along with needle age was detected near all pollution sources. Leaching of Mn from needles and especially from soil as a cause of decreased needle concentrations is discussed

Decontaminate feature for tracking: adaptive tracking via evolutionary feature subset

Science.gov (United States)

Liu, Qiaoyuan; Wang, Yuru; Yin, Minghao; Ren, Jinchang; Li, Ruizhi

2017-11-01

Although various visual tracking algorithms have been proposed in the last 2-3 decades, it remains a challenging problem for effective tracking with fast motion, deformation, occlusion, etc. Under complex tracking conditions, most tracking models are not discriminative and adaptive enough. When the combined feature vectors are inputted to the visual models, this may lead to redundancy causing low efficiency and ambiguity causing poor performance. An effective tracking algorithm is proposed to decontaminate features for each video sequence adaptively, where the visual modeling is treated as an optimization problem from the perspective of evolution. Every feature vector is compared to a biological individual and then decontaminated via classical evolutionary algorithms. With the optimized subsets of features, the "curse of dimensionality" has been avoided while the accuracy of the visual model has been improved. The proposed algorithm has been tested on several publicly available datasets with various tracking challenges and benchmarked with a number of state-of-the-art approaches. The comprehensive experiments have demonstrated the efficacy of the proposed methodology.

76 FR 38024 - Standards of Performance for New Stationary Sources

Science.gov (United States)

2011-06-29

... January 20, 1983. O Sewage Treatment Plants X X P Primary Copper Smelters X X Q Primary Zinc Smelters X X R Primary Lead Smelters X X S Primary Aluminum Reduction Plants X X T Phosphate Fertilizer Industry: X X Wet Process Phosphoric Acid Plants. U Phosphate Fertilizer Industry: X X Superphosphoric Acid...

Fast-track totalknæalloplastik

DEFF Research Database (Denmark)

Gromov, Kirill; Kristensen, Billy B; Jørgensen, Christoffer Calov

2017-01-01

patients are eligible for fast-track TKA, and hence the fast-track concept should be standard at all joint replacement facilities. Future challenges of fast-track TKA include safe introduction of outpatient protocols, acute and chronic pain after surgery and optimal utilization of post......Fast-track total knee arthroplasty (TKA) is a well-established concept including optimized logistics and evidence-based treatment, focusing on minimizing surgical stress and improved post-operative recovery, thus leading to lower mortality and morbidity as well as high patient satisfaction. All...

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.

Alcan Kitimat smelter modernization project remedial action scheme functional requirements

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-09-09

This paper identified remedial actions for reducing islanding and voltage collapse at the Alcan Kitimat smelter modernization project. The study was conducted after an earlier study indicated that the proposed project significantly increased electricity loads and stresses on Alcan's power system. Remedial actions included shedding the appropriate number of Kemano (KMO) generators; reducing Kitimat potline loads by de-saturating saturable reactors and lowering tap changers; and shedding potlines to preserve the Kitimat auxiliary load and facilitate power restoration. Power flow and transient stability studies were conducted to evaluate the impact of the remedial actions on the KMO generators and the transmission system. Results showed that fast load reduction improved power system response. Load reduction by changing the converter transformer tap reduced significant amounts of loads, but was too slow to be effective during fast voltage collapse. The study showed that although the remedial action scheme (RAS) reduced the impact of various contingencies on the Alcan system, performance was degraded due to the significant load increase. Fast load shedding capability was also reduced. It was concluded that further research is needed to develop and implement the RAS. 3 tabs., 7 figs.

Visualisation and quantification of heavy metal accessibility in smelter slags: The influence of morphology on availability.

Science.gov (United States)

Morrison, Anthony L; Swierczek, Zofia; Gulson, Brian L

2016-03-01

The Imperial Smelting Furnace (ISF) for producing lead and zinc simultaneously has operated on four continents and in eleven countries from the 1950's. One of the process changes that the ISF introduced was the production of a finely granulated slag waste. Although this slag contained significant amounts of residual lead (Pb) and zinc (Zn), because of its glassy nature it was considered environmentally benign. From the Cockle Creek smelter near Boolaroo at the northern end of Lake Macquarie, NSW, Australia, it is estimated that around 2.1 million tonnes of the fine slag was distributed into the community and most remains where it was originally utilised. Residual tonnages of slag of this magnitude are common worldwide wherever the ISF operated. Studies of base metal smelting slags have concluded that mineralogical and morphological characteristics of the slag play a critical role in moderating environmental release of toxic elements. Scanning electron microscopy (SEM) and microanalysis of the ISF slags has shown that the Pb and associated elements are present as discrete nodules (∼6-22 μm) in the slag and that they are not associated with Zn which is contained in the glass slag phase. Using an automated SEM and analysis technique (QEMSCAN(®)) to "map" the mineralogical structure of the particles, it was possible to quantitatively determine the degree of access infiltrating fluids might have to the reaction surface of the Pb phases. The level of access decreases with increasing particle size, but in even the largest sized particles (-3350 + 2000 μm) nearly 80% of the Pb-containing phases were totally or partially accessible. These results provide evidence that the toxic elements in the slags are not contained by the glassy phase and will be vulnerable to leaching over time depending on their individual phase reactivity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Minimum and Full Fluidization Velocity for Alumina Used in the Aluminum Smelter

Directory of Open Access Journals (Sweden)

Paulo Douglas S. de Vasconcelos

2011-11-01

Full Text Available Fluidization is an engineering unit operation that occurs when a fluid (liquid or gas ascends through a bed of particles, and these particles get a velocity of minimum fluidization enough to stay in suspension, but without carrying them in the ascending flow. As from this moment the powder behaves as liquid at boiling point, hence the term “fluidization”. This operation is widely used in the aluminum smelter processes, for gas dry scrubbing (mass transfer and in a modern plant for continuous alumina pot feeding (particles’ momentum transfer. The understanding of the alumina fluoride rheology is of vital importance in the design of fluidized beds for gas treatment and fluidized pipelines for pot feeding. This paper shows the results of the experimental and theoretical values of the minimum and full fluidization velocities for the alumina fluoride used to project the state of the art round non‐metallic air‐fluidized conveyor of multiples outlets.

Lead-Related Genetic Loci, Cumulative Lead Exposure and Incident Coronary Heart Disease: The Normative Aging Study

Science.gov (United States)

Weisskopf, Marc G.; Sparrow, David; Schwartz, Joel; Hu, Howard; Park, Sung Kyun

2016-01-01

Background Cumulative exposure to lead is associated with cardiovascular outcomes. Polymorphisms in the δ-aminolevulinic acid dehydratase (ALAD), hemochromatosis (HFE), heme oxygenase-1 (HMOX1), vitamin D receptor (VDR), glutathione S-transferase (GST) supergene family (GSTP1, GSTT1, GSTM1), apolipoprotein E (APOE),angiotensin II receptor-1 (AGTR1) and angiotensinogen (AGT) genes, are believed to alter toxicokinetics and/or toxicodynamics of lead. Objectives We assessed possible effect modification by genetic polymorphisms in ALAD, HFE, HMOX1, VDR, GSTP1, GSTT1, GSTM1, APOE, AGTR1 and AGT individually and as the genetic risk score (GRS) on the association between cumulative lead exposure and incident coronary heart disease (CHD) events. Methods We used K-shell-X-ray fluorescence to measure bone lead levels. GRS was calculated on the basis of 22 lead-related loci. We constructed Cox proportional hazard models to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CHD. We applied inverse probability weighting to account for potential selection bias due to recruitment into the bone lead sub-study. Results Significant effect modification was found by VDR, HMOX1, GSTP1, APOE, and AGT genetic polymorphisms when evaluated individually. Further, the bone lead-CHD associations became larger as GRS increases. After adjusting for potential confounders, a HR of CHD was 2.27 (95%CI: 1.50–3.42) with 2-fold increase in patella lead levels, among participants in the top tertile of GRS. We also detected an increasing trend in HRs across tertiles of GRS (p-trend = 0.0063). Conclusions Our findings suggest that lead-related loci as a whole may play an important role in susceptibility to lead-related CHD risk. These findings need to be validated in a separate cohort containing bone lead, lead-related genetic loci and incident CHD data. PMID:27584680

Long-term dynamics of heavy metals in the upper horizons of soils in the region of a copper smelter impacts during the period of reduced emission

Science.gov (United States)

Vorobeichik, E. L.; Kaigorodova, S. Yu.

2017-08-01

The 23-year-long dynamics of actual acidity (pHwater) and acid-soluble heavy metals (Cu, Pb, Cd, Zn) in the forest litter and humus horizon of soils in spruce-fir forests were studied in the area subjected to the long-term (since 1940) pollution with atmospheric emissions from the Middle Ural Copper Smelter (Revda, Sverdlovsk oblast). For this purpose, 25 permanent sample plots were established on lower slopes at different distances from the enterprise (30, 7, 4, 2, and 1 km; 5 plots at each distance) in 1989. The emissions from the smelter have decreased since the early 1990s. In 2012, the emissions of sulfur dioxide and dust decreased by 100 and 40 times, respectively, as compared with the emissions in 1980. Samples of litter and humus horizons were collected on permanent plots in 1989, 1999, and 2012. The results indicate that the pH of the litter and humus horizons restored to the background level 10 and 23 years after the beginning of the reduction in emissions, respectively. However, these characteristics in the impact zone still somewhat differ from those in the background area. In 2012, the content of Cu in the litter decreased compared to 1989 on all the plots; the content of Cu in the humus horizon decreased only in the close vicinity of the smelter. The contents of other metals in the litter and humus horizons remain constant or increased (probably because of the pH-dependent decrease in migration capacity). The absence of pronounced removal of metals from soils results in the retention of high contamination risk and the conservation of the suppressed state of biota within the impact zone.

Alteration of podzolized tills by acid load near Ni-Cu smelters at Monchegorsk, Kola Peninsula, Russia

Directory of Open Access Journals (Sweden)

Räisänen, M.L.

1994-06-01

Full Text Available Mineralogy and geochemistry of podzolized tills was studied in the area of dieback forest near the Ni-Cu smelters at Monchegorsk, and less extensively forest damage near by Apatity and Kirovsk in the Russian Kola Peninsula. The abundances of main elements (Si, Al, Fe, Mg, Ca, K, Na in the <64 μm fraction were determined by the hot aqua regia digestion method and inductively coupled plasma spectrometry. The clay mineralogy of the silt plus clay fraction was examined by X-ray diffraction after selective extraction and heating treatments. At all study sites, trioctahedral mica and chlorite were totally weathered from the silt and clay fraction (<64 μm of the eluvial layer, leaving behind interstratified mica-vermiculite-smectite clays. In general, the mixed-layer clay of the eluvial layer had low levels of hydroxy interlayering. Illuviated layers were characterized by hydroxy interlayered vermiculite-chlorite. The abundance of chlorite and mica was greater, and the degree of interlayering lower, in parent tills than in the overlying illuviated layers. Regardless of differences in bedrock and till geochemistry, the weathering sequence throughout the podzolized till profile was coherent at most of the sampling sites. Exceptionally, in a few profiles sampled at the totally destroyed forest site, the swelling mixed-layer clay of the eluvial layer displayed a neochloritized structure. On the basis of XRD patterns and geochemistry of the samples, it was inferred that a short-term decomposition of plagioclase had promoted, via inputs of Al-hydroxides, the transformation of mica-vermiculite-smectite to a poorly crystalline interstratification of chlorite-aluminous montmorillonite. The accelerated weathering occurring occasionally in exposed places was probably activated by the strongly acidic load in the vicinity of the smelters and the city of Monchegorsk.

Advanced alignment of the ATLAS tracking system

CERN Document Server

AUTHOR|(CDS)2085334; The ATLAS collaboration

2016-01-01

In order to reconstruct the trajectories of charged particles, the ATLAS experiment exploits a tracking system built using different technologies, silicon planar modules or microstrips (PIX and SCT detectors) and gaseous drift tubes (TRT), all embedded in a 2T solenoidal magnetic field. Misalignments of the active detector elements and deformations of the structures (which can lead to \\textit{Weak Modes}) deteriorate resolution of the track reconstruction and lead to systematic biases on the measured track parameters. The applied alignment procedures exploit various advanced techniques in order to minimise track-hit residuals and remove detector deformations. For the LHC Run II, the Pixel Detector has been refurbished and upgraded with the installation of a new pixel layer, the Insertable B-layer (IBL).

Neuropsychological studies in children with elevated tooth-lead concentrations. II. Extended study

Energy Technology Data Exchange (ETDEWEB)

Winneke, G; Kraemer, U; Brockhaus, A; Ewers, U; Kujanek, G; Lechner, H; Janke, W

1983-01-01

Results from neuropsychological tests, collected under double-blind-precautions, were evaluated for 115 schoolage children (mean age: 9.4 years) living in a lead smelter area (Stolberg, FRG). Tooth-lead concentrations (PbT) from shed incisor teeth as measures of longtime lead-exposure were available for these children (mean . 6.16 ppm; range: 1.9-38.5 ppm), and for 83 of them blood-lead concentrations (PbB) were available as well (mean . 14.3 micrograms/dl; range: 6.8-33.8 micrograms/dl). The following functional capacities were tested: intelligence (German WISC), perceptual-motor integration (Goettinger Formreproduktionstest . GFT, Diagnosticum for Cerebralschaedigung . DCS), reaction performance (Wiener Determinationsgeraet), finger-wrist tapping-speed, and repetitive cancellation-performance (Differentieller Leistungstest). In addition standardized behavior ratings were obtained by the examiners, the mothers, and the teachers. Multiple stepwise regression-analysis (forced solution) was calculated for outcome-variables and Pb-tooth, including age, sex, duration of labor, and socio-hereditary background as covariates. The results are discussed within the framework of attention-deficit disorder, and compared to neurobehavioral Pb-effects from animal-experiments, which provide suggestive evidence for a causal relationship between developmental lead-exposure and certain neurobehavioral deficits.

78 FR 25185 - Delegation of New Source Performance Standards and National Emission Standards for Hazardous Air...

Science.gov (United States)

2013-04-30

... Sewage Treatment Plants X X X X P Primary Copper Smelters X X X X Q Primary Zinc Smelters X X X X R Primary Lead Smelters X X X X S Primary Aluminum Reduction Plants.... X X X X T Phosphate Fertilizer Industry: Wet X X X X Process Phosphoric Acid Plants. U Phosphate Fertilizer Industry: X X X X...

Rapid Analysis of Copper Ore in Pre-Smelter Head Flow Slurry by Portable X-ray Fluorescence.

Science.gov (United States)

Burnett, Brandon J; Lawrence, Neil J; Abourahma, Jehad N; Walker, Edward B

2016-05-01

Copper laden ore is often concentrated using flotation. Before the head flow slurry can be smelted, it is important to know the concentration of copper and contaminants. The concentration of copper and other elements fluctuate significantly in the head flow, often requiring modification of the concentrations in the slurry prior to smelting. A rapid, real-time analytical method is needed to support on-site optimization of the smelter feedstock. A portable, handheld X-ray fluorescence spectrometer was utilized to determine the copper concentration in a head flow suspension at the slurry origin. The method requires only seconds and is reliable for copper concentrations of 2.0-25%, typically encountered in such slurries. © The Author(s) 2016.

Analysis of copper losses throughout weak acid effluent flows generated during off-gas treatment in the New Copper Smelter RTB Bor

Directory of Open Access Journals (Sweden)

Dragana Ivšić-Bajčeta

2013-09-01

Full Text Available The previous inadequate treatment of off-gas in RTB Bor in Serbia has resulted in serious pollution of the environment and the possibly high losses of copper through the effluent flows. The project of New Copper Smelter RTB Bor, besides the new flash smelting furnace (FSF and the reconstruction of Pierce-Smith converter (PSC, includes more effective effluent treatment. Paper presents an analysis of the new FSF and PSC off-gas treatment, determination of copper losses throughout generated wastewaters and discussion of its possible valorization. Assumptions about the solubility of metals phases present in the FSF and PSC off-gas, obtained by the treatment process simulation, were compared with the leaching results of flue dusts. Determined wastewaters characteristics indicate that the PSC flow is significantly richer in copper, mostly present in insoluble metallic/sulfide form, while the FSF flow has low concentration of copper in the form of completely soluble oxide/sulfate. The possible scenario for the copper valorization, considering arsenic and lead as limiting factors, is the separation of the FSF and PSC flows, return of the metallic/sulfide solid phase to the smelting process and recovery from the sulfate/oxide liquid phase.

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.......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...

Inhibiting Interference - a grounded theory of health professionals' pattern of behaviour related to the relatives of older patients in fast-track treatment programmes

DEFF Research Database (Denmark)

Berthelsen, Connie Bøttcher; Lindhardt, Tove; Frederiksen, Kirsten

2014-01-01

AIM: To generate a grounded theory explaining health professionals' pattern of behaviour and experience related to the relatives of older patients in fast-track treatment programmes during total joint replacement. BACKGROUND: Health professionals uphold standardised care for patients, and effect...... on quality is seen when relatives support patients during total joint replacement. Since health professionals often have problematic relationships with relatives, knowledge is needed of the health professionals' pattern of behaviour in relation to relatives of older patients in fast-track treatment programme....... DESIGN: Grounded theory according to Glaser's methodology was used to generate substantive theory of health professionals' pattern of behaviour. METHODS: Data were collected from 2010 to 2011 by 44 health professionals in orthopaedic wards at two Danish hospitals. Data from nonparticipant observations...

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.

Plant reactions as indicators of air pollution in the vicinity of a copper smelter

Directory of Open Access Journals (Sweden)

Jerzy Fabiszewski

2014-01-01

Full Text Available Several higher plant species and epiphytic lichen Hypogymnia physodes (L. Nyl. were examined in the vicinity of a copper smelter. The investigations included field experiments. Ecological surveys of some biotests and bioreactions using exposure of higher plants and transplanted lichens were critically appraised. Such basic processes of plants as photosynthesis and respiration, as well as the quantitative composition of chlorophyll pigments were used as biotests. The results indicate that the photosynthesis intensity is the most useful measure for the estimation of the effect of both heavy metal and SO2 pollutants. The degrees of chlorophyll degradation were in keeping with visual symptoms of injuries. For the ecological monitoring the measurement of respiration intensity, especially in lichens is not recommended. All applied biotests are presented in maps illustrating the degree of degradation of the area examined.

Multiparametric electronic devices based on nuclear tracks

Energy Technology Data Exchange (ETDEWEB)

Fink, D. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany)], E-mail: FINK@HMI.DE; Saad, A. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Basic Science Department, Faculty of Science, Al Balqa University, Salt (Jordan); Dhamodaran, S. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); School of Physics, University of Hyderabad, Hyderabad 500 046 (India); Chandra, A. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Department of Physics and Astrophysics, University of Delhi, Delhi 110 007 (India); Fahrner, W.R. [Chair of Electronic Devices, Institute of Electrotechnique, Fernuniversitaet, Hagen (Germany); Hoppe, K. [South Westfalia University of Applied Sciences, Hagen (Germany); Chadderton, L.T. [Institute of Advanced Studies, ANU Canberra, GPO Box 4, ACT (Australia)

2008-08-15

An overview is given on a family of novel electronic devices consisting of an insulating layer containing conducting or semiconducting nuclear tracks, deposited on a semiconducting substrate, and connected by at least one back and two surface contacts. Conducting and semiconducting latent tracks may emerge directly from swift heavy ion irradiation. Etched tracks in insulators can be filled with adequate materials to make them conducting or semiconducting. For this purpose metallic or semiconducting nanoclusters were deposited. We have denoted termed these devices made with latent tracks as 'tunable electronic anisotropic material on semiconductor' (TEAMS), if based on latent ion tracks, and as 'tunable electronic material in pores in oxide on semiconductor' (TEMPOS), if based on etched tracks. Depending on the band-to-band transition between tracks and substrate and on the ratio of surface to track conductivity, the current/voltage characteristics of TEAMS and TEMPOS structures can be modified in many different ways leading to tunable resistors, capacitors and diodes. Both devices show negative differential resistances. This should enable tunable tunneldiodes. TEAMS or TEMPOS structures can be controlled by various external physical and/or chemical parameters leading to sensors. It is even possible to combine different input currents and/or external parameters according to AND/OR logics. The currents through a clustered layer on a TEMPOS structure can be described by the Barbasi-Albert model of network theory enabling to calculate a 'radius of influence'r{sub ROI} around each surface contact, beyond which neighboring contacts do not influence each other. The radius of influence can be well below 1{mu}m leading to nanometric TEMPOS structures.

Multiparametric electronic devices based on nuclear tracks

International Nuclear Information System (INIS)

Fink, D.; Saad, A.; Dhamodaran, S.; Chandra, A.; Fahrner, W.R.; Hoppe, K.; Chadderton, L.T.

2008-01-01

An overview is given on a family of novel electronic devices consisting of an insulating layer containing conducting or semiconducting nuclear tracks, deposited on a semiconducting substrate, and connected by at least one back and two surface contacts. Conducting and semiconducting latent tracks may emerge directly from swift heavy ion irradiation. Etched tracks in insulators can be filled with adequate materials to make them conducting or semiconducting. For this purpose metallic or semiconducting nanoclusters were deposited. We have denoted termed these devices made with latent tracks as 'tunable electronic anisotropic material on semiconductor' (TEAMS), if based on latent ion tracks, and as 'tunable electronic material in pores in oxide on semiconductor' (TEMPOS), if based on etched tracks. Depending on the band-to-band transition between tracks and substrate and on the ratio of surface to track conductivity, the current/voltage characteristics of TEAMS and TEMPOS structures can be modified in many different ways leading to tunable resistors, capacitors and diodes. Both devices show negative differential resistances. This should enable tunable tunneldiodes. TEAMS or TEMPOS structures can be controlled by various external physical and/or chemical parameters leading to sensors. It is even possible to combine different input currents and/or external parameters according to AND/OR logics. The currents through a clustered layer on a TEMPOS structure can be described by the Barbasi-Albert model of network theory enabling to calculate a 'radius of influence'r ROI around each surface contact, beyond which neighboring contacts do not influence each other. The radius of influence can be well below 1μm leading to nanometric TEMPOS structures

Lead isotopic fingerprinting of aerosols to characterize the sources of atmospheric lead in an industrial city of India

Science.gov (United States)

Sen, Indra S.; Bizimis, Michael; Tripathi, Sachchida Nand; Paul, Debajyoti

2016-03-01

Anthropogenic Pb in the environment is primarily sourced from combustion of fossil fuel and high-temperature industries such as smelters. Identifying the sources and pathways of anthropogenic Pb in the environment is important because Pb toxicity is known to have adverse effects on human health. Pb pollution sources for America, Europe, and China are well documented. However, sources of atmospheric Pb are unknown in India, particularly after leaded gasoline was phased out in 2000. India has a developing economy with a rapidly emerging automobile and high temperature industry, and anthropogenic Pb emission is expected to rise in the next decade. In this study, we report on the Pb-isotope compositions and trace metal ratios of airborne particulates collected in Kanpur, a large city in northern part of India. The study shows that the PM10 aerosols had elevated concentration of Cd, Pb, Zn, As, and Cu in the Kanpur area, however their concentrations are well below the United States Environmental Protection Agency chronic exposure limit. Lead isotopic and trace metal data reveal industrial emission as the plausible source of anthropogenic Pb in the atmosphere in Kanpur. However, Pb isotopic compositions of potential source end-members are required to fully evaluate Pb contamination in India over time. This is the first study that characterizes the isotopic composition of atmospheric Pb in an Indian city after leaded gasoline was phased out by 2000.

American-Soviet Track and Field Exchanges as a Tool of Shaping Bilateral Political Relations

Directory of Open Access Journals (Sweden)

Michał Marcin Kobierecki

2017-04-01

Full Text Available The aim of the research is to investigate the track and field exchanges between the United States and the Soviet Union in the Cold War era, in search of their role in shaping bilateral relations between the two states. Particular attention has been paid to the motivation of respective subjects. The research allowed to test the hypothesis stating that the track and field exchanges were an attempt to bring the two countries closer and to achieve propaganda benefits simultaneously.

A Relative View on Tracking Error

NARCIS (Netherlands)

W.G.P.M. Hallerbach (Winfried); I. Pouchkarev (Igor)

2005-01-01

textabstractWhen delegating an investment decisions to a professional manager, investors often anchor their mandate to a specific benchmark. The manager’s exposure to risk is controlled by means of a tracking error volatility constraint. It depends on market conditions whether this constraint is

Future changes in extratropical storm tracks and baroclinicity under climate change

International Nuclear Information System (INIS)

Lehmann, Jascha; Coumou, Dim; Frieler, Katja; Eliseev, Alexey V; Levermann, Anders

2014-01-01

The weather in Eurasia, Australia, and North and South America is largely controlled by the strength and position of extratropical storm tracks. Future climate change will likely affect these storm tracks and the associated transport of energy, momentum, and water vapour. Many recent studies have analyzed how storm tracks will change under climate change, and how these changes are related to atmospheric dynamics. However, there are still discrepancies between different studies on how storm tracks will change under future climate scenarios. Here, we show that under global warming the CMIP5 ensemble of coupled climate models projects only little relative changes in vertically averaged mid-latitude mean storm track activity during the northern winter, but agree in projecting a substantial decrease during summer. Seasonal changes in the Southern Hemisphere show the opposite behaviour, with an intensification in winter and no change during summer. These distinct seasonal changes in northern summer and southern winter storm tracks lead to an amplified seasonal cycle in a future climate. Similar changes are seen in the mid-latitude mean Eady growth rate maximum, a measure that combines changes in vertical shear and static stability based on baroclinic instability theory. Regression analysis between changes in the storm tracks and changes in the maximum Eady growth rate reveal that most models agree in a positive association between the two quantities over mid-latitude regions. (letter)

PROGNOSTIC QUALITY OF MOTOR AND MORPHOLOGICAL FACTORS IN RELATION TO TRACK AND FIELD EVENTS OF SPRINT AND JUMPING TYPE

Directory of Open Access Journals (Sweden)

Kemal Idrizović

2009-11-01

Full Text Available Assessment of the impact of motor manifestations and morphological features on the quality in the realization of track and field events of sprint and jumping type was the main issue of this research. The aim of the paper was to establish the impact of the ap- plied predictor systems of variables, motor and morphological ones, on the criteria va- riables, the results in track and field events: long jump and 60m sprint event. The results obtained in this research lead to the conclusion that this type of track and field events, or the quality of their realization in the motor sense mostly depends on the locomotive complexes of similar structure. However, in the morphological sense, such impact is va- riable.

The relationship between fission track length and track density in apatite

International Nuclear Information System (INIS)

Laslett, G.M.; Gleadow, A.J.W.; Duddy, I.R.

1984-01-01

Fission track dating is based upon an age equation derived from a random line segment model for fission tracks. This equation contains the implicit assumption of a proportional relationship between the true mean length of fission tracks and their track density in an isotropic medium. Previous experimental investigation of this relationship for both spontaneous and induced tracks in apatite during progressive annealment model in an obvious fashion. Corrected equations relating track length and density for apatite, an anisotropic mineral, show that the proportionality in this case is between track density and a length factor which is a generalization of the mean track length combining the actual length and crystallographic orientation of the track. This relationship has been experimentally confirmed for induced tracks in Durango apatite, taking into account bias in sampling of the track lengths, and the effect of the bulk etching velocity. (author)

[An epidemiological survey on saturnism among children due to lead pollution released from township enterprise].

Science.gov (United States)

Li, Heng-xin; Song, Ya-li; Li, Hong-guang; Yuan, Yong-xin; Xu, Qing; Liu, En-xu; Li, Jin-song

2008-03-01

To understand the current situations of saturnism and blood lead levels of children resided in village and circumjacent areas, and to know its relations with sex, age and other factors on children' s health as to providing some evidences for prevention and control. An epidemiological survey was conducted for finding out the pollution sources and for a better understanding of the surrounding environment. All 221 children under 14 years old, from the lead pollution villages and surrounding establishments were enrolled, and their blood lead levels were detected by graphite atomizer absorption spectrophotometer method. Symptoms of the saturnism were investigated through a standardized questionnaire. SPSS13.0 software was administrated for data analysis. High blood lead level identification rate was 66.06% (146/221), and saturnism rate 32.13% (71/221). The children's blood lead levels among group 1, group 2, group 3 in this village and jade factory were (161.20 +/- 32.94), (176.60 +/- 43.62), (258.00 +/-106.08) and (238.01 +/- 55.20) microg/L respectively and the significant differences were observed through Kruskal-Wallis test (chi2 = 51.84, df= 3, Plead levels of children from group 3 in this village and the jade factory were higher than those of other two groups. No correlation was found between children's age and blood lead level (r = 0.10, P = 0.13). There was a significant difference in blood lead levels between boys and girls (t' = 3.83, Plead levels rising, the occurrence rate of main saturnism symptoms was significantly increased. This survey suggested that the pollution source was a coarse lead smelter. The blood lead level should ke overwhelmingly increased among children who live nearby the higher level of lead blood, that living nearby the lead smeltery,might result in stautnism and negative effect on children's healthy.

Deaths related to lead poisoning in the United States, 1979-1998

International Nuclear Information System (INIS)

Kaufmann, R.B.; Staes, Catherine J.; Matte, Thomas D.

2003-01-01

This study was conducted to describe trends in US lead poisoning-relate deaths between 1979 and 1998. The predictive value of relevant ICD-9 codes was also evaluated. Multiple cause-of-death files were searched for record containing relevant ICD-9 codes, and underlying causes and demographic characteristics were assessed. For 1979-1988, death certificates were reviewed; lead source information was abstracted and accuracy of coding was determined. An estimated 200 lead poisoning-related deaths occurred from 1979 to 1998. Most were among males (74%), Blacks (67%), adults of age ≥45 years (76%), and Southerners (70%). The death rate was significantly lower in more recent years. An alcohol-related code was a contributing cause for 28% of adults. Only three of nine ICD-9 codes for lead poisoning were highl predictive of lead poisoning-related deaths. In conclusion, lead poisoning-related death rates have dropped dramatically since earlier decades and are continuing to decline. However, the findings imply that moonshine ingestion remains a source of high-dose lead exposure in adults

A simplified Track Assembler I/O for the Muon Trigger Track Finder

CERN Document Server

Dallavalle, Gaetano-Marco; Genchev, Vladimir; Grandi, Claudio; Neumeister, Norbert; Porth, Paul; Rohringer, Herbert

1998-01-01

One of the architectural concerns in the present design of the Muon Trigger Track Finder ( MTTF) is the large number of inputs to the Track Assembler ( TA). In the TA block, input track segment pairs from many Extrapolation Units ( EU) are associated into tracks. The relative contribution of these inputs to the assembled tracks is studied with simulated track patterns for low and high pt muons over the entire eta, phi acceptance of the CMS barrel. A pruning of the EUs is proposed which does not alter the performance of the Track Finder and minimizes the interconnections between azimuthal wedges.

A test of the stability of Cd, Cu, Hg, Pb and Zn profiles over two decades in lake sediments near the Flin Flon Smelter, Manitoba, Canada

Energy Technology Data Exchange (ETDEWEB)

Percival, J.B.; Outridge, P.M., E-mail: outridge@nrcan.gc.ca

2013-06-01

Lake sediments are valuable archives of atmospheric metal deposition, but the stability of some element profiles may possibly be affected by diagenetic changes over time. In this extensive case study, the stability of sedimentary Cd, Cu, Hg, Pb and Zn profiles was assessed in dated sediment cores that were collected in 2004 from four smelter-affected lakes near Flin Flon, Manitoba, which had previously been cored in 1985. Metal profiles determined in 1985 were in most cases clearly reproduced in the corresponding sediment layers in 2004, although small-scale spatial heterogeneity in metal distribution complicated the temporal comparisons. Pre-smelter (i.e. pre-1930) increases in metal profiles were likely the result of long-range atmospheric metal pollution, coupled with particle mixing at the 1930s sediment surface. However, the close agreement between key inflection points in the metal profiles sampled two decades apart suggests that metals in most of the lakes, and Hg and Zn in the most contaminated lake (Meridian), were stable once the sediments were buried below the surface mixed layer. Cadmium, Cu and Pb profiles in Meridian Lake did not agree as well between studies, showing evidence of upward remobilization over time. Profiles of redox-indicator elements (Fe, Mn, Mo and U) suggested that the rate of Mn oxyhydroxide recycling within sediment was more rapid in Meridian Lake, which may have caused the Cd, Cu and Pb redistribution. - Highlights: • Sedimentary Cd, Cu, Hg, Pb and Zn profiles in four lakes were mostly unchanged over 19 years. • In one lake, Cd, Cu and Pb profiles were offset relative to the originals. • The offset could indicate diagenetic upcore dispersal of these metals.

Comparison of the U.S. lead recycling industry in 1998 and 2011

Science.gov (United States)

Wilburn, David R.

2014-01-01

Since 1998, the structure of the lead recycling industry has changed and trade patterns of the domestic lead recycling industry have shifted. Although the domestic demand for lead has remained relatively constant since 1998, production of lead has increasingly shifted to the domestic secondary lead industry. The last primary lead smelter in the United States closed at the end of 2013, at which time the secondary lead industry became the sole source of domestic lead production. The amount of lead recovered annually from scrap batteries generally increased from about 900,000 metric tons in 1995 to more than 1,100,000 metric tons in 2012. The percentage of total U.S. lead production attributed to battery scrap increased from 65 percent in 1995 to 87 percent in 2012. Since the North American Free Trade Agreement took effect in 1994, trade patterns among the United States, Canada, and Mexico have changed for recycled lead products. In the late 1990s, the principal sources of lead waste and scrap not derived from batteries were Canada, Mexico, and South America; by 2011, the principal sources were Central America and Asia, with decreasing amounts from Canada and South America. Since 1998, the amount of lead derived from imported batteries and scrap from Canada has ranged from 50 to 90 percent, and the amount imported from Mexico has ranged from 3 to 20 percent. Canada received about 50 percent of the lead contained in spent lead-acid batteries and scrap exported from the United States in 1998, and Mexico received about 4 percent. By 2012, however, the amount of lead scrap exported to Canada had decreased to about 10 percent, and the amount of lead-based scrap products, primarily batteries, exported to Mexico from the United States had increased to 47 percent. Vertical integration of the domestic secondary lead industry and higher costs required to implement more stringent ambient air standards in the United States have led some companies to shift lead recycling

Dependence of yield of nuclear track-biosensors on track radius and analyte concentration

Science.gov (United States)

García-Arellano, H.; Muñoz H., G.; Fink, D.; Vacik, J.; Hnatowicz, V.; Alfonta, L.; Kiv, A.

2018-04-01

In swift heavy ion track-based polymeric biosensor foils with incorporated enzymes one exploits the correlation between the analyte concentration and the sensor current, via the enrichment of charged enzymatic reaction products in the track's confinement. Here we study the influence of the etched track radius on the biosensor's efficiency. These sensors are analyte-specific only if both the track radii and the analyte concentration exceed certain threshold values of ∼15 nm and ∼10-6 M (for glucose sensing), respectively. Below these limits the sensor signal stems un-specifically from any charge carrier. In its proper working regime, the inner track walls are smoothly covered by enzymes and the efficiency is practically radius independent. Theory shows that the measured current should be slightly sub-proportional to the analyte concentration; the measurements roughly reconfirm this. Narrower tracks (∼5-15 nm radius) with reduced enzyme coverage lead to decreasing efficiency. Tiny signals visible when the tracks are etched to effective radii between 0 and ∼5 nm are tentatively ascribed to enzymes bonded to surface-near nano-cracks in the polymer foil, resulting from its degradation due to aging, rather than to the tracks. Precondition for this study was the accurate determination of the etched track radii, which is possible only by a nanofluidic approach. This holds to some extent even for enzyme-covered tracks, though in this case most of the wall charges are compensated by enzyme bonding.

Tracking adaptation and measuring development

Energy Technology Data Exchange (ETDEWEB)

Brooks, Nick; Anderson, Simon; Ayers, Jessica; Burton, Ian; Tellam, Ian

2011-11-15

This is the first paper in the new IIED Climate Change Working Paper series. As adaptation to climate change becomes the focus of increasing attention and the target of significant spending, there is a growing need for frameworks and tools that enable organisations to track and assess the outcomes of adaptation interventions. This paper presents a coherent framework for climate change adaptation programming, including potential indicators, or indicator categories/types, for tracking and evaluating the success of adaptation support and adaptation interventions. The paper begins with a discussion of some of the key issues related to the evaluation of adaptation, and outlines some of the main difficulties and constraints with respect to the development of adaptation indicators. Next, an evaluation framework is proposed and indicator categories or 'domains' are identified. Lastly, key conclusions are provided and a theory of change is outlined that shows how development and use of the framework could lead to more effective adaptation investments for climate resilient development.

Tracking black holes in numerical relativity

International Nuclear Information System (INIS)

Caveny, Scott A.; Anderson, Matthew; Matzner, Richard A.

2003-01-01

This work addresses the problem of generically tracking black hole event horizons in computational simulation of black hole interactions. Solutions of the hyperbolic eikonal equation, solved on a curved spacetime manifold containing black hole sources, are employed in development of a robust tracking method capable of continuously monitoring arbitrary changes of topology in the event horizon as well as arbitrary numbers of gravitational sources. The method makes use of continuous families of level set viscosity solutions of the eikonal equation with identification of the black hole event horizon obtained by the signature feature of discontinuity formation in the eikonal's solution. The method is employed in the analysis of the event horizon for the asymmetric merger in a binary black hole system. In this first such three dimensional analysis, we establish both qualitative and quantitative evidence for our method and its application to the asymmetric problem. We focus attention on (1) the topology of the throat connecting the holes following merger, (2) the time of merger, and (3) continuing to account for the surface of section areas of the black hole sources

ANNOTATION SUPPORTED OCCLUDED OBJECT TRACKING

Directory of Open Access Journals (Sweden)

Devinder Kumar

2012-08-01

Full Text Available Tracking occluded objects at different depths has become as extremely important component of study for any video sequence having wide applications in object tracking, scene recognition, coding, editing the videos and mosaicking. The paper studies the ability of annotation to track the occluded object based on pyramids with variation in depth further establishing a threshold at which the ability of the system to track the occluded object fails. Image annotation is applied on 3 similar video sequences varying in depth. In the experiment, one bike occludes the other at a depth of 60cm, 80cm and 100cm respectively. Another experiment is performed on tracking humans with similar depth to authenticate the results. The paper also computes the frame by frame error incurred by the system, supported by detailed simulations. This system can be effectively used to analyze the error in motion tracking and further correcting the error leading to flawless tracking. This can be of great interest to computer scientists while designing surveillance systems etc.

Modeling self-occlusions in dynamic shape and appearance tracking

KAUST Repository

Yang, Yanchao

2013-12-01

We present a method to track the precise shape of a dynamic object in video. Joint dynamic shape and appearance models, in which a template of the object is propagated to match the object shape and radiance in the next frame, are advantageous over methods employing global image statistics in cases of complex object radiance and cluttered background. In cases of complex 3D object motion and relative viewpoint change, self-occlusions and disocclusions of the object are prominent, and current methods employing joint shape and appearance models are unable to accurately adapt to new shape and appearance information, leading to inaccurate shape detection. In this work, we model self-occlusions and dis-occlusions in a joint shape and appearance tracking framework. Experiments on video exhibiting occlusion/dis-occlusion, complex radiance and background show that occlusion/dis-occlusion modeling leads to superior shape accuracy compared to recent methods employing joint shape/appearance models or employing global statistics. © 2013 IEEE.

Gender, age, and sport differences in relative age effects among US Masters swimming and track and field athletes.

Science.gov (United States)

Medic, Nikola; Young, Bradley W; Starkes, Janet L; Weir, Patricia L; Grove, J Robert

2009-12-01

A relative age effect has been identified in Masters sports (Medic, Starkes, & Young, 2007). Since gender, age, and type of sport have been found to influence the relative age effect in youth sports (Musch & Grondin, 2001), we examined how these three variables influenced possible relative age effects among Masters swimmers and track and field athletes. Using archived data between 1996 and 2006, frequency of participation entries and record-setting performances at the US Masters championships were examined as a function of an individual's constituent year within any 5-year age category. Study 1 investigated the frequency of Master athletes who participated; Study 2 examined the frequency of performance records that were set across constituent years within an age category, while accounting for the distribution of participation frequencies. Results showed that a participation-related relative age effect in Masters sports is stronger for males, that it becomes progressively stronger with each successive decade of life, and that it does not differ across track and field and swimming. In addition, a performance-related relative age effect in Masters sport seems to be stronger for swimming than track and field, but it does not differ across gender and decades of life.

Possible use of electron beam treatment for removal of SO2 in off-gases from copper smelters. Preliminary tests results

International Nuclear Information System (INIS)

Villanueva, L.; Ahumanda, L.; Chmielewski, A.; Zimek, A.; Budka, S.; Licki, J.

1996-01-01

The Chilean Nuclear Energy Commission is currently performing a previous feasibility study concerning possible utilization of electron-beam process for removal of SO 2 from different types of sulfurous streams from copper smelters. First part of the project was related to verify, in a experimental line at Institute of Nuclear Chemistry and Technology, INCT, Poland, the behaviour of the process for simulated off-gases with very high SO 2 content, between 5% to 15% by volume. Tests were performed at laboratory stage and with flowrate of 5 Nm 3 /hr, using an ILU-6 electron accelerator, with the following results: High removal efficiencies of SO 2 , up to 90% were achieved for simulated off-gases containing up to 15% of SO 2 ; Required dose was in the range 5 to 8 kGy; Big influence of NH 3 stoichiometry and gas humidity on SO 2 removal efficiency; Rapid generation of sub-micron solid by-product, in great amount, that causes deposits on ducts and filtration units. This work presents the experimental results and discuss is technical projections in the field of interest. (author)

Particle tracking

International Nuclear Information System (INIS)

Mais, H.; Ripken, G.; Wrulich, A.; Schmidt, F.

1986-02-01

After a brief description of typical applications of particle tracking in storage rings and after a short discussion of some limitations and problems related with tracking we summarize some concepts and methods developed in the qualitative theory of dynamical systems. We show how these concepts can be applied to the proton ring HERA. (orig.)

Eye tracking in user experience design

CERN Document Server

Romano Bergstorm, Jennifer

2014-01-01

Eye Tracking for User Experience Design explores the many applications of eye tracking to better understand how users view and interact with technology. Ten leading experts in eye tracking discuss how they have taken advantage of this new technology to understand, design, and evaluate user experience. Real-world stories are included from these experts who have used eye tracking during the design and development of products ranging from information websites to immersive games. They also explore recent advances in the technology which tracks how users interact with mobile devices, large-screen displays and video game consoles. Methods for combining eye tracking with other research techniques for a more holistic understanding of the user experience are discussed. This is an invaluable resource to those who want to learn how eye tracking can be used to better understand and design for their users. * Includes highly relevant examples and information for those who perform user research and design interactive experi...

Tracking a convoy of multiple targets using acoustic sensor data

Science.gov (United States)

Damarla, T. R.

2003-08-01

In this paper we present an algorithm to track a convoy of several targets in a scene using acoustic sensor array data. The tracking algorithm is based on template of the direction of arrival (DOA) angles for the leading target. Often the first target is the closest target to the sensor array and hence the loudest with good signal to noise ratio. Several steps were used to generate a template of the DOA angle for the leading target, namely, (a) the angle at the present instant should be close to the angle at the previous instant and (b) the angle at the present instant should be within error bounds of the predicted value based on the previous values. Once the template of the DOA angles of the leading target is developed, it is used to predict the DOA angle tracks of the remaining targets. In order to generate the tracks for the remaining targets, a track is established if the angles correspond to the initial track values of the first target. Second the time delay between the first track and the remaining tracks are estimated at the highest correlation points between the first track and the remaining tracks. As the vehicles move at different speeds the tracks either compress or expand depending on whether a target is moving fast or slow compared to the first target. The expansion and compression ratios are estimated and used to estimate the predicted DOA angle values of the remaining targets. Based on these predicted DOA angles of the remaining targets the DOA angles obtained from the MVDR or Incoherent MUSIC will be appropriately assigned to proper tracks. Several other rules were developed to avoid mixing the tracks. The algorithm is tested on data collected at Aberdeen Proving Ground with a convoy of 3, 4 and 5 vehicles. Some of the vehicles are tracked and some are wheeled vehicles. The tracking algorithm results are found to be good. The results will be presented at the conference and in the paper.

Lead phytotoxicity in soils and nutrient solutions is related to lead induced phosphorus deficiency

International Nuclear Information System (INIS)

Cheyns, Karlien; Peeters, Sofie; Delcourt, Dorien; Smolders, Erik

2012-01-01

This study was set up to relate lead (Pb) bioavailability with its toxicity to plants in soils. Tomato and barley seedlings were grown in six different PbCl 2 spiked soils (pH: 4.7–7.4; eCEC: 4.2–41.7 cmol c /kg). Soils were leached and pH corrected after spiking to exclude confounding factors. Plant growth was halved at 1600–6500 mg Pb/kg soil for tomato and at 1900–8300 mg Pb/kg soil for barley. These soil Pb threshold were unrelated to soil pH, organic carbon, texture or eCEC and neither soil solution Pb nor Pb 2+ ion activity adequately explained Pb toxicity among soils. Shoot phosphorus (P) concentrations significantly decreased with increasing soil Pb concentrations. Tomato grown in hydroponics at either varying P supply or at increasing Pb (equal initial P) illustrated that shoot P explained growth response in both scenarios. The results suggest that Pb toxicity is partially related to Pb induced P deficiency, likely due to lead phosphate precipitation. - Highlights: ► Tomato and barley shoot growth was affected by Pb toxicity in six different soils. ► Soil properties did not explain differences in plant Pb toxicity among soils. ► Neither soil solution Pb nor Pb 2+ ion activity explained Pb toxicity among soils. ► Shoot phosphorus concentration decreased with increasing soil Pb concentrations. ► Lead induced a P deficiency in plants, likely due to lead phosphate precipitation. - Soil properties did not explain differences in plant lead toxicity among different soils. Shoot phosphorus concentration decreased with increasing soil lead concentrations.

Designing and Simulation of a Two-Axis Solar Tracking System by Exact Relations of Solar Angles

Directory of Open Access Journals (Sweden)

Faezeh Esmaili Ranjbar

2013-01-01

Full Text Available In this study, a system has been designed and simulated to track sunlight, which identifies sun location based on the exact relations of solar angles and without any optical sensor. In fact the relations which have been used in this study are far more accurate compared to similar cases, because of using the "equation of time" and reducing the tracking time of every 15 minutes. In this system, an economical micro-controller has been used to generate the necessary orders to control system and two stepper motors for powering solar array. By adding a real-time clock IC (RTC to angle differentiation circuit, dynamic plane has improved.

How Visual Search Relates to Visual Diagnostic Performance: A Narrative Systematic Review of Eye-Tracking Research in Radiology

Science.gov (United States)

van der Gijp, A.; Ravesloot, C. J.; Jarodzka, H.; van der Schaaf, M. F.; van der Schaaf, I. C.; van Schaik, J. P.; ten Cate, Th. J.

2017-01-01

Eye tracking research has been conducted for decades to gain understanding of visual diagnosis such as in radiology. For educational purposes, it is important to identify visual search patterns that are related to high perceptual performance and to identify effective teaching strategies. This review of eye-tracking literature in the radiology…

Magnetic properties of alluvial soils contaminated with lead, zinc and cadmium

Science.gov (United States)

Petrovský, E.; Kapička, A.; Jordanova, N.; Borůvka, L.

2001-09-01

Several proxy methods have been used recently to outline increased levels of pollution. One of them is based on measurements of the concentration of (ferri)magnetic minerals of anthropogenic origin. This method has been used recently in the mapping of both polluted and unpolluted areas. In order to validate this method, a more detailed study of links between magnetic parameters characterising the physical shape of magnetic minerals and concentrations of heavy metals is needed. In this study, we analysed the magnetic characteristics of alluvial soils, formed as a result of several breakdowns of wet deposit sink of ashes from a lead ore smelter. The soils were previously analysed for concentration of lead, zinc and cadmium. Our results show that in this case of a shared source of heavy metals and magnetic minerals, simple measurements of magnetic susceptibility discriminate well between polluted and clean areas. In addition, the concentration pattern agrees with the concentrations of the heavy metals studied in deeper soil layers that were not affected by post-depositional changes due to climate and remediation efforts.

ALICE: Simulated lead-lead collision

CERN Multimedia

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.

Study of the effects induced by lead on the emulsion films of the OPERA experiment

CERN Document Server

Anokhina, A.; Ariga, A.; Arrabito, L.; Autiero, D.; Badertscher, A.; Bay, F.; Bergnoli, A.; Bersani Greggio, F.; Besnier, M.; Bick, D.; Bozza, C.; Brugiere, T.; Brugnera, R.; Brunetti, G.; Buontempo, S.; Carrara, E.; Cazes, A.; Chaussard, L.; Chernyavsky, M.; Chiarella, V.; Chon-Sen, N.; Chukanov, A.; Consiglio, L.; Cozzi, M.; Dal Corso, F.; D'Amato, G.; D'Ambrosio, N.; De Lellis, G.; Declais, Y.; De Serio, M.; Di Capua, F.; Di Ferdinando, D.; Di Giovanni, A.; Di Marco, N.; Di Troia, C.; Dmitrievski, S.; Dominjon, A.; Dracos, M.; Duchesneau, D.; Dulach, B.; Dusini, S.; Ebert, J.; Egorov, O.; Enikeev, R.; Ereditato, A.; Esposito, L.S.; Favier, J.; Felici, G.; Ferber, T.; Fini, R.; Franceschi, A.; Fukuda, T.; Fukushima, C.; Galkin, V.I.; Galkin, V.A.; Garfagnini, A.; Giacomelli, G.; Giorgini, M.; Goellnitz, C.; Golubkov, D.; Gornoushkin, Y.; Grella, G.; Grianti, F.; Guler, M.; Gusev, G.; Gustavino, C.; Hagner, Caren; Hara, T.; Hierholzer, M.; Hiramatsu, S.; Hoshino, Kaoru; Ieva, M.; Jakovcic, K.; Janicsko Csathy, J.; Janutta, B.; Jollet, C.; Juget, F.; Kawai, T.; Kazuyama, M.; Kim, S.H.; Kimura, M.; Knuesel, J.; Kodama, K.; Komatsu, M.; Kose, U.; Kreslo, I.; Laktineh, I.; Lazzaro, C.; Lenkeit, J.; Ljubicic, A.; Longhin, Andrea; Lutter, G.; Manai, K.; Mandrioli, G.; Manzoor, S.; Marotta, A.; Marteau, J.; Matsuoka, H.; Mauri, N.; Meisel, F.; Meregaglia, A.; Messina, M.; Migliozzi, P.; Miyamoto, S.; Monacelli, P.; Morishima, K.; Moser, U.; Muciaccia, M.T.; Naganawa, N.; Naka, T.; Nakamura, M.; Nakamura, T.; Nakano, T.; Nikitina, V.; Niwa, K.; Nonoyama, Y.; Ogawa, S.; Osedlo, V.; Ossetski, D.; Paoloni, A.; Park, B.D.; Park, I.G.; Pastore, A.; Patrizii, L.; Pennacchio, E.; Pessard, H.; Pistillo, C.; Polukhina, N.; Pozzato, M.; Pretzl, K.; Publichenko, P.; Pupilli, F.; Roganova, T.; Rosa, G.; Rostovtseva, I.; Rubbia, A.; Russo, A.; Ryazhskaya, O.; Ryzhikov, D.; Sato, Y.; Sato, O.; Saveliev, V.; Sazhina, G.; Schembri, A.; Scotto Lavina, L.; Shibuya, H.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Song, J.S.; Spinetti, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Strauss, T.; Strolin, Paolo Emilio; Sugonyaev, V.; Taira, Y.; Takahashi, S.; Tenti, M.; Terranova, F.; Tioukov, V.; Togo, V.; Tolun, P.; Tsarev, V.; Tufanli, S.; Ushida, N.; Valieri, C.; Vilain, P.; Vladimirov, M.; Votano, L.; Vuilleumier, J.L.; Wilquet, G.; Wonsak, B.; Wurtz, J.; Yoon, C.S.; Yoshida, J.; Zaitsev, Y.; Zemskova, S.; Zghiche, A.; Zimmermann, R.

2008-01-01

The OPERA neutrino oscillation experiment is based on the use of the Emulsion Cloud Chamber (ECC). In the OPERA ECC, nuclear emulsion films acting as very high precision tracking detectors are interleaved with lead plates providing a massive target for neutrino interactions. We report on studies related to the effects occurring from the contact between emulsion and lead. A low radioactivity lead is required in order to minimize the number of background tracks in emulsions and to achieve the required performance in the reconstruction of neutrino events. It was observed that adding other chemical elements to the lead, in order to improve the mechanical properties, may significantly increase the level of radioactivity on the emulsions. A detailed study was made in order to choose a lead alloy with good mechanical properties and an appropriate packing technique so as to have a low enough effective radioactivity.

Characterizing Zinc Speciation in Soils from a Smelter-Affected Boreal Forest Ecosystem.

Science.gov (United States)

Hamilton, Jordan G; Farrell, Richard E; Chen, Ning; Feng, Renfei; Reid, Joel; Peak, Derek

2016-03-01

HudBay Minerals, Inc., has mined and/or processed Zn and Cu ore in Flin Flon, MB, Canada, since the 1930s. The boreal forest ecosystem and soil surrounding these facilities have been severely impacted by mixed metal contamination and HSO deposition. Zinc is one of the most prevalent smelter-derived contaminants and has been identified as a key factor that may be limiting revegetation. Metal toxicity is related to both total concentrations and speciation; therefore, X-ray absorption spectroscopy and X-ray fluorescence mapping were used to characterize Zn speciation in soils throughout the most heavily contaminated areas of the landscape. Zinc speciation was linked to two distinct soil types. Group I soils consist of exposed soils in weathered positions of bedrock outcrops with Zn present primarily as franklinite, a (ZnFeO) spinel mineral. Group II soils are stabilized by an invasive metal-tolerant grass species, with Zn found as a mixture of octahedral (Fe oxides) and tetrahedral Mn oxides) adsorption complexes with a franklinite component. Soil erosion influences Zn speciation through the redistribution of Zn and soil particulates from Group I landscape positions to Group II soils. Despite Group II soils having the highest concentrations of CaCl-extractable Zn, they support metal-tolerant plant growth. The metal-tolerant plants are probably preferentially colonizing these areas due to better soil and nutrient conditions as a result of soil deposition from upslope Group I areas. Zinc concentration and speciation appears to not influence the colonization by metal-tolerant grasses, but the overall soil properties and erosion effects prevent the revegetation by native boreal forest species. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Development and validation of a lead emission inventory for the Greater Cairo area

Directory of Open Access Journals (Sweden)

Zeinab Safar

2014-09-01

Full Text Available Studies that investigate the environmental health risks to Cairo residents invariably conclude that lead is one of the area’s major health hazards. The Cairo Air Improvement Project (CAIP, which was implemented by a team led by Chemonics International, funded by USAID in partnership with the Egyptian Environmental Affairs Agency (EEAA, started developing a lead emission inventory for the greater Cairo (GC area in 1998. The inventory contains a list by major source of the annual lead emissions in the GC area. Uses of the inventory and associated database include developing effective regulatory and control strategies, assessing emissions trends, and conducting modeling exercises. This paper describes the development of the current lead emissions inventory (1999–2010, along with an approach to develop site specific emission factors and measurements to validate the inventory. This paper discusses the major sources of lead in the GC area, which include lead smelters, Mazout (heavy fuel oil combustion, lead manufacturing batteries factories, copper foundries, and cement factories. Included will be the trend in the lead emissions inventory with regard to the production capacity of each source category. In addition, the lead ambient measurements from 1999 through 2010 are described and compared with the results of Source Attribution Studies (SAS conducted in 1999, 2002, and 2010. Due to EEAA/CAIP efforts, a remarkable decrease in more than 90% in lead emissions was attained for 2007.

Interpreting major industrial landscapes: Social follow-up on meanings, the case of two aluminium smelters, Alcan (Alma, Canada) and Pechiney (Dunkirk, France)

International Nuclear Information System (INIS)

Fortin, Marie-Jose; Gagnon, Christiane

2006-01-01

Landscape is becoming an object of growing social concern and, as such, an object of mediation between major industrial producers and local communities. The question of the capacity of environmental assessment to address this issue is thus raised. Until now, landscape studies have focused on visual aspects, although subjective dimensions such as perceptions and meanings have been recognised. The research in this article concerns the subjective dimensions, and is presented with a view to further the understanding of the process of the social interpretation of landscape as it relates to heavy industrial sites. Within a socioconstructivist perspective, two case studies (a longitudinal follow-up and an ex-post) of two aluminum smelters, one in Alma (Quebec, Canada) and the other in Dunkirk (France) were conducted. The results show that nearby residents' interpretations of landscape varied according to three sets of factors related to 1) the dynamics of regional development and the historical place of industry in the community, 2) the relationship between residents and the industry and local governance capacities, and 3) the social impacts experienced. To conclude, three ways of using qualitative methodologies for social and environmental follow-up in a socioconstructivist approach to landscape are proposed

Final Scientific/Technical Report for Subseasonal to Seasonal Prediction of Extratropical Storm Track Activity over the U.S. using NMME data

Energy Technology Data Exchange (ETDEWEB)

Chang, Edmund Kar-Man [Stony Brook Univ., NY (United States)

2017-10-30

The goals of the project are: 1) To develop and assess subseasonal to seasonal prediction products for storm track activity derived from NMME data; 2) Assess how much of the predictable signal can be associated with ENSO and other modes of large scale low frequency atmosphere-ocean variability; and 3) Further explore the link between storm track variations and extreme weather statistics. Significant findings of this project include the followings: 1) Our assessment of NMME reforecasts of storm track variability has demonstrated that NMME models have substantial skill in predicting storm track activity in the vicinity of North America - Subseasonal skill is high only for leads of less than 1 month. However, seasonal (winter) prediction skill near North America is high even out to 4 to 5 months lead - Much of the skill for leads of 1 month or longer is related to the influence of ENSO - Nevertheless, lead 0 NMME predictions are significantly more skillful than those based on ENSO influence 2) Our results have demonstrated that storm track variations highly modulate the frequency of occurrence of weather extremes - Extreme cold, high wind, and extreme precipitation events in winter - Extreme heat events in summer - These results suggest that NMME storm track predictions can be developed to serve as a useful guidance to assist the formulation of monthly/seasonal outlooks

Coupling geochemical, mineralogical and microbiological approaches to assess the health of contaminated soil around the Almalyk mining and smelter complex, Uzbekistan

International Nuclear Information System (INIS)

Shukurov, Nosir; Kodirov, Obidjon; Peitzsch, Mirko; Kersten, Michael; Pen-Mouratov, Stanislav; Steinberger, Yosef

2014-01-01

This study describes the impact of airborne pollution resulting from mining and smelting activities on the soils of the Almalyk mining and industrial area (NE Uzbekistan). Samples were collected along a transect downwind of the industrial area. Enriched contents of some metals were found in the upper soil layers near the metallurgical complex (Zn ≤ 3010 mg kg −1 , Pb ≤ 630 mg kg −1 , Cd ≤ 30 mg kg −1 ) which suggests that these metals were derived from local stack emissions. The morphology and internal microstructure of metal-bearing spherical particles found in the heavy mineral fraction suggest that these particles were probably a result of inefficient flue gas cleaning technique of the smelter. The highest metal concentrations were found also in soil solutions and exchangeable solid fractions from the first three locations, and decreased with increasing distance from the pollution source along transect. Thermodynamic equilibrium calculations suggest that the mobile metal pool in the contaminated soil is mainly controlled by dissolution of metal carbonates formed as weathering product of the metalliferous particles. The health of the microbiological soil ecosystem was assessed by measurements of basal respiration, nematode abundance, biomass-related C and N content, and microbial metabolic quotient qCO 2 . Significant correlations were found between the dissolved metal content and the microbiological health parameters, a negative one for C mic /C org ratio, and a positive one for qCO 2 . A negative correlation was found between the amount of nematodes and the metal contents suggesting that the contaminated soil has significant impact on the functioning of the microbiological community. A better understanding of the spatial variations in the whole ecosystem functioning due to airborne impact could be very useful for establishing suitable land use and best management practices for the polluted areas. - Highlights: • Soil samples were collected along a

Coupling geochemical, mineralogical and microbiological approaches to assess the health of contaminated soil around the Almalyk mining and smelter complex, Uzbekistan

Energy Technology Data Exchange (ETDEWEB)

Shukurov, Nosir; Kodirov, Obidjon; Peitzsch, Mirko [Geosciences Institute, Johannes Gutenberg University, Mainz 55099 (Germany); Kersten, Michael, E-mail: kersten@uni-mainz.de [Geosciences Institute, Johannes Gutenberg University, Mainz 55099 (Germany); Pen-Mouratov, Stanislav; Steinberger, Yosef [The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900 (Israel)

2014-04-01

This study describes the impact of airborne pollution resulting from mining and smelting activities on the soils of the Almalyk mining and industrial area (NE Uzbekistan). Samples were collected along a transect downwind of the industrial area. Enriched contents of some metals were found in the upper soil layers near the metallurgical complex (Zn ≤ 3010 mg kg{sup −1}, Pb ≤ 630 mg kg{sup −1}, Cd ≤ 30 mg kg{sup −1}) which suggests that these metals were derived from local stack emissions. The morphology and internal microstructure of metal-bearing spherical particles found in the heavy mineral fraction suggest that these particles were probably a result of inefficient flue gas cleaning technique of the smelter. The highest metal concentrations were found also in soil solutions and exchangeable solid fractions from the first three locations, and decreased with increasing distance from the pollution source along transect. Thermodynamic equilibrium calculations suggest that the mobile metal pool in the contaminated soil is mainly controlled by dissolution of metal carbonates formed as weathering product of the metalliferous particles. The health of the microbiological soil ecosystem was assessed by measurements of basal respiration, nematode abundance, biomass-related C and N content, and microbial metabolic quotient qCO{sub 2}. Significant correlations were found between the dissolved metal content and the microbiological health parameters, a negative one for C{sub mic}/C{sub org} ratio, and a positive one for qCO{sub 2}. A negative correlation was found between the amount of nematodes and the metal contents suggesting that the contaminated soil has significant impact on the functioning of the microbiological community. A better understanding of the spatial variations in the whole ecosystem functioning due to airborne impact could be very useful for establishing suitable land use and best management practices for the polluted areas. - Highlights: • Soil

Elastic tracking versus neural network tracking for very high multiplicity problems

International Nuclear Information System (INIS)

Harlander, M.; Gyulassy, M.

1991-04-01

A new Elastic Tracking (ET) algorithm is proposed for finding tracks in very high multiplicity and noisy environments. It is based on a dynamical reinterpretation and generalization of the Radon transform and is related to elastic net algorithms for geometrical optimization. ET performs an adaptive nonlinear fit to noisy data with a variable number of tracks. Its numerics is more efficient than that of the traditional Radon or Hough transform method because it avoids binning of phase space and the costly search for valid minima. Spurious local minima are avoided in ET by introducing a time-dependent effective potential. The method is shown to be very robust to noise and measurement error and extends tracking capabilities to much higher track densities than possible via local road finding or even the novel Denby-Peterson neural network tracking algorithms. 12 refs., 2 figs

Photovoltaic High-Frequency Pulse Charger for Lead-Acid Battery under Maximum Power Point Tracking

Directory of Open Access Journals (Sweden)

Hung-I. Hsieh

2013-01-01

Full Text Available A photovoltaic pulse charger (PV-PC using high-frequency pulse train for charging lead-acid battery (LAB is proposed not only to explore the charging behavior with maximum power point tracking (MPPT but also to delay sulfating crystallization on the electrode pores of the LAB to prolong the battery life, which is achieved due to a brief pulse break between adjacent pulses that refreshes the discharging of LAB. Maximum energy transfer between the PV module and a boost current converter (BCC is modeled to maximize the charging energy for LAB under different solar insolation. A duty control, guided by a power-increment-aided incremental-conductance MPPT (PI-INC MPPT, is implemented to the BCC that operates at maximum power point (MPP against the random insolation. A 250 W PV-PC system for charging a four-in-series LAB (48 Vdc is examined. The charging behavior of the PV-PC system in comparison with that of CC-CV charger is studied. Four scenarios of charging statuses of PV-BC system under different solar insolation changes are investigated and compared with that using INC MPPT.

The Relation Between Blood Lead Levels and Osteoporosis in Turkish Women

Directory of Open Access Journals (Sweden)

Nurver Turfaner Ertürk

2004-03-01

Full Text Available Lead is a toxic heavy element which is to 90% deposited in bone until the 6th decade and is given to the blood with pregnancy, lactation and physiologic osteoporosis. When it is over certain amounts it may cause osteoporosis and an increase in cardiac events and cancer. In order to evaluate the effect of menopause and osteoporosis on blood lead 20 post-menopausal osteoporotic, 19 non-osteoporotic and 21 pre-menopausal women were selected and their blood levels were measured. In post-menopausal women, its relation with bone mineral density was also investigated. There was no difference between osteoporotic and non-osteoporotic women and pre and postmenopausal women in terms of blood lead (Pb. There was no relation between age and Pb levels but in non-osteoporotic postmenopausal women there was a negative correlation between Pb levels and duration of menopause. There was no relation between bone mineral density and blood lead whereas blood lead and environmental pollution displayed a meaningful correlation.

How visual search relates to visual diagnostic performance: a narrative systematic review of eye-tracking research in radiology.

Science.gov (United States)

van der Gijp, A; Ravesloot, C J; Jarodzka, H; van der Schaaf, M F; van der Schaaf, I C; van Schaik, J P J; Ten Cate, Th J

2017-08-01

Eye tracking research has been conducted for decades to gain understanding of visual diagnosis such as in radiology. For educational purposes, it is important to identify visual search patterns that are related to high perceptual performance and to identify effective teaching strategies. This review of eye-tracking literature in the radiology domain aims to identify visual search patterns associated with high perceptual performance. Databases PubMed, EMBASE, ERIC, PsycINFO, Scopus and Web of Science were searched using 'visual perception' OR 'eye tracking' AND 'radiology' and synonyms. Two authors independently screened search results and included eye tracking studies concerning visual skills in radiology published between January 1, 1994 and July 31, 2015. Two authors independently assessed study quality with the Medical Education Research Study Quality Instrument, and extracted study data with respect to design, participant and task characteristics, and variables. A thematic analysis was conducted to extract and arrange study results, and a textual narrative synthesis was applied for data integration and interpretation. The search resulted in 22 relevant full-text articles. Thematic analysis resulted in six themes that informed the relation between visual search and level of expertise: (1) time on task, (2) eye movement characteristics of experts, (3) differences in visual attention, (4) visual search patterns, (5) search patterns in cross sectional stack imaging, and (6) teaching visual search strategies. Expert search was found to be characterized by a global-focal search pattern, which represents an initial global impression, followed by a detailed, focal search-to-find mode. Specific task-related search patterns, like drilling through CT scans and systematic search in chest X-rays, were found to be related to high expert levels. One study investigated teaching of visual search strategies, and did not find a significant effect on perceptual performance. Eye

Development of etched nuclear tracks

International Nuclear Information System (INIS)

Somogyi, G.

1980-01-01

The theoretical description of the evolution of etched tracks in solid state nuclear track detectors is considered for different initial conditions, for the cases of constant and varying track etch rates, isotropic and anisotropic bulk etching as well as for thick and thin detectors. It is summarized how one can calculate the main parameters of etch-pit geometry, the track length, the axes of a surface track opening, track profile and track contour. The application of the theory of etch-track evolution is demonstrated with selected practical problems. Attention is paid to certain questions related to the determination of unknown track parameters and calculation of surface track sizes. Finally, the theory is extended to the description of the perforation and etch-hole evolution process in thin detectors, which is of particular interest for track radiography and nuclear filter production. (orig.)

Development of etched nuclear tracks

International Nuclear Information System (INIS)

Somogyi, G.

1979-01-01

The theoretical description of the evolution of etched tracks in solid state nuclear track detectors is considered for different initial conditions, for the cases of constant and varying track etch rates, isotopic and unisotropic bulk etching as well as for thick and thin detectors. It is summarized how the main parameters of etch-pit geometry, the track length, the axes of a surface track opening, the track profile and the track contour can be calculated. The application of the theory of etch-track evolution is demonstrated with selected practical problems. Attention is paid to certain questions related to the determination of unknown track parameters and calculation of surface track sizes. Finally, the theory is extended to the description of the perforation and etch-hole evolution process in thin detectors, which is of particular interest for track radiography and nuclear filter production. (author)

Self-Tracking: Reflections from the BodyTrack Project.

Science.gov (United States)

Wright, Anne

2016-07-06

Based on the author's experiences the practice of self-tracking can empower individuals to explore and address issues in their lives. This work is inspired by examples of people who have reclaimed their wellness through an iterative process of noticing patterns of ups and downs, trying out new ideas and strategies, and observing the results. In some cases, individuals have realized that certain foods, environmental exposures, or practices have unexpected effects for them, and that adopting custom strategies can greatly improve quality of life, overcoming chronic problems. Importantly, adopting the role of investigator of their own situation appears to be transformative: people who embarked on this path changed their relationship to their health situation even before making discoveries that helped lead to symptom improvement. The author co-founded the BodyTrack project in 2010 with the goal of empowering a broader set of people to embrace this investigator role in their own lives and better address their health and wellness concerns, particularly those with complex environmental or behavioral components. The core of the BodyTrack system is an open source web service called Fluxtream ( https://fluxtream.org ) that allows users to aggregate, visualize, and reflect on data from myriad sources on a common timeline. The project is also working to develop and spread peer coaching practices to help transfer the culture and skills of self-tracking while mentoring individuals in how to self-assess their own situation and guide the process for themselves.

Eye tracking social preferences

NARCIS (Netherlands)

Jiang, Ting; Potters, Jan; Funaki, Yukihiko

We hypothesize that if people are motivated by a particular social preference, then choosing in accordance with this preference will lead to an identifiable pattern of eye movements. We track eye movements while subjects make choices in simple three-person distribution experiments. We characterize

Statistical modelling of railway track geometry degradation using Hierarchical Bayesian models

International Nuclear Information System (INIS)

Andrade, A.R.; Teixeira, P.F.

2015-01-01

Railway maintenance planners require a predictive model that can assess the railway track geometry degradation. The present paper uses a Hierarchical Bayesian model as a tool to model the main two quality indicators related to railway track geometry degradation: the standard deviation of longitudinal level defects and the standard deviation of horizontal alignment defects. Hierarchical Bayesian Models (HBM) are flexible statistical models that allow specifying different spatially correlated components between consecutive track sections, namely for the deterioration rates and the initial qualities parameters. HBM are developed for both quality indicators, conducting an extensive comparison between candidate models and a sensitivity analysis on prior distributions. HBM is applied to provide an overall assessment of the degradation of railway track geometry, for the main Portuguese railway line Lisbon–Oporto. - Highlights: • Rail track geometry degradation is analysed using Hierarchical Bayesian models. • A Gibbs sampling strategy is put forward to estimate the HBM. • Model comparison and sensitivity analysis find the most suitable model. • We applied the most suitable model to all the segments of the main Portuguese line. • Tackling spatial correlations using CAR structures lead to a better model fit

Automated vehicle for railway track fault detection

Science.gov (United States)

Bhushan, M.; Sujay, S.; Tushar, B.; Chitra, P.

2017-11-01

For the safety reasons, railroad tracks need to be inspected on a regular basis for detecting physical defects or design non compliances. Such track defects and non compliances, if not detected in a certain interval of time, may eventually lead to severe consequences such as train derailments. Inspection must happen twice weekly by a human inspector to maintain safety standards as there are hundreds and thousands of miles of railroad track. But in such type of manual inspection, there are many drawbacks that may result in the poor inspection of the track, due to which accidents may cause in future. So to avoid such errors and severe accidents, this automated system is designed.Such a concept would surely introduce automation in the field of inspection process of railway track and can help to avoid mishaps and severe accidents due to faults in the track.

[The influence of occupational lead exposure on transmural repolarization dispersion].

Science.gov (United States)

Zyśko, Dorota; Gajek, Jacek; Chlebda, Ewa; Mazurek, Walentyna

2005-02-01

The parts of QT interval: time from Q wave to the peak of T wave (QTp) representing the de- and repolarization of subepicardial layer and the time from the peak of T wave to its end (QTp-e) building the transmural dispersion of repolarization enable more exact assessment of repolarization period of the heart muscle. Occupational exposure to lead influences the electrophysiologic properties of the heart. The aim of our study was to assess the QTp and QTp-e interval in workers occupationally exposed to lead. The study was carried out in 22 copper smelters aged 41.8 +/- 8.7 years, occupationally exposed to lead. The control group consisted of 14 healthy men. In all studied subjects blood lead concentration (Pb) and the concentration of free protoporphyrins in erytrocytes were assessed. 24-hour ECG holter monitoring was done to study rhythm disturbances and the duration in lead CM5 of QT interval, QTp interval, RR interval preceding the assessed QT interval (pRR) during sleep, rest during the awake state and moderate daily activity. The QTp-e interval is the difference between the duration of QT and QTp interval. The duration of QTp and QTp-e in occupationally exposed workers and healthy persons did not differ significantly. These parameters were significantly lower in both groups during moderately physical activity comparing to the values during sleep. The QTp-e/ QTp ratio in occupationally exposed workers during night hours was significantly lower than during daily activity what was not the case in control persons. Occupational exposure to lead do not change significantly the transmural dispersion of repolarization. Occupational exposure to lead diminishes the QTp-e/QTp ratio during the night.

FORMATION OF CHLOROPYROMORPHITE IN A LEAD-CONTAMINATED SOIL AMENDED WITH HYDROXYAPATITE

Science.gov (United States)

To evaluate conversion of soil Pb to pyromorphite, a Pb contaminated soil collected adjacent to a historical smelter was reacted with hydroxyapatite in a traditional incubation experiment and in a dialysis system in which the soil and hydroxyapatite solids were separated by a dia...

Relatives in older patients' fast-track treatment programme during total hip or knee replacement. A grounded theory study

DEFF Research Database (Denmark)

Berthelsen, Connie Bøttcher

and considerate support in concern for the patients; Substituting mode, with practical and cognitive support; and Adapting mode, by trying to fit in with the patients’ and health professionals’ requirements. Study II: 16 patients aged 70 to 94 were included and data was collected through 15 non......The aim of this Ph.D.-dissertation was to generate grounded theories of relatives, patients, and health professionals’ pattern of behaviour, respectively, in relation to the relatives of older patients’ fast-track treatment programmes during total hip or knee replacement. The dissertation includes...... to the older patients’ self-determination of being autonomous and how they adapt and are perceived in the health professionals’ environment. This may be useful to the health professionals in orthopaedic fast-track treatment programmes and their future collaboration with older patients and their relatives....

Multi-criteria Analysis of Air Pollution with SO(2) and PM(10) in Urban Area Around the Copper Smelter in Bor, Serbia.

Science.gov (United States)

Nikolić, Djordje; Milošević, Novica; Mihajlović, Ivan; Zivković, Zivan; Tasić, Viša; Kovačević, Renata; Petrović, Nevenka

2010-02-01

This work presents the results of 4 years long monitoring of concentrations of SO(2) gas and PM(10) in the urban area around the copper smelter in Bor. The contents of heavy metals Pb, Cd, Cu, Ni, and As in PM(10) were determined and obtained values were compared to the limit values provided in EU Directives. Manifold excess concentrations of all the components in the atmosphere of the urban area of the townsite Bor were registered. Through application of a multi-criteria analysis by using PROMETHEE/GAIA method, the zones were ranked according to the level of pollution.

The railway track and its long term behaviour a handbook for a railway track of high quality

CERN Document Server

Tzanakakis, Konstantinos

2013-01-01

A proper quality of a track and other infrastructure objects represents a basic requirement for train safety and punctuality. Most of the physical systems and their components deteriorate over time. This affects performance and may lead to failures. Albert Einstein said, “You have to learn the rules of the game. And then you have to play better than anyone else.” Only if we understand how the whole system works, taking into account its imperfections and how they influence its quality and performance will we be able to learn the rules of the game and “play better.” The book provides the readers with the necessary functional knowledge of track behaviour and comprehensively covers the function of the various track components, their interaction as elements of the track system, as well as the interaction of the track with railway vehicles. By presenting important tools for a deep understanding of track-behaviour this book aims to be a reference guide for infrastructure managers and to help them to find way...

Binomial distribution of Poisson statistics and tracks overlapping probability to estimate total tracks count with low uncertainty

International Nuclear Information System (INIS)

Khayat, Omid; Afarideh, Hossein; Mohammadnia, Meisam

2015-01-01

In the solid state nuclear track detectors of chemically etched type, nuclear tracks with center-to-center neighborhood of distance shorter than two times the radius of tracks will emerge as overlapping tracks. Track overlapping in this type of detectors causes tracks count losses and it becomes rather severe in high track densities. Therefore, tracks counting in this condition should include a correction factor for count losses of different tracks overlapping orders since a number of overlapping tracks may be counted as one track. Another aspect of the problem is the cases where imaging the whole area of the detector and counting all tracks are not possible. In these conditions a statistical generalization method is desired to be applicable in counting a segmented area of the detector and the results can be generalized to the whole surface of the detector. Also there is a challenge in counting the tracks in densely overlapped tracks because not sufficient geometrical or contextual information are available. It this paper we present a statistical counting method which gives the user a relation between the tracks overlapping probabilities on a segmented area of the detector surface and the total number of tracks. To apply the proposed method one can estimate the total number of tracks on a solid state detector of arbitrary shape and dimensions by approximating the tracks averaged area, whole detector surface area and some orders of tracks overlapping probabilities. It will be shown that this method is applicable in high and ultra high density tracks images and the count loss error can be enervated using a statistical generalization approach. - Highlights: • A correction factor for count losses of different tracks overlapping orders. • For the cases imaging the whole area of the detector is not possible. • Presenting a statistical generalization method for segmented areas. • Giving a relation between the tracks overlapping probabilities and the total tracks

Fast-track knee arthroplasty – status and future challenges

DEFF Research Database (Denmark)

Kehlet, Henrik; Thienpont, Emmanuel

2013-01-01

Fast-track programs have been developed for different surgical procedures leading to higher patient satisfaction and lower morbidity. This concept has been extended to knee arthroplasty in recent years. The purpose of this narrative review was to discuss the different aspects of fast-track knee...... arthroplasty....

Tissue metal levels in Muskrat (Ondatra zibethica) collected near the Sudbury (Ontario) ore-smelters; prospects for biomonitoring marsh pollution

Energy Technology Data Exchange (ETDEWEB)

Parker, G.H

2004-05-01

An examination of tissue metal levels in Sudbury-area muskrat (Ondatra zibethica) revealed that animals collected in the vicinity of the local ore-smelters contained elevated burdens of Cd and Ni in their liver and kidneys. Respective tissue concentrations averaged 2-fold and 3- to 6-fold higher than background values and are believed to reflect accumulations resulting from food chain contamination in regional marshes, including that reportedly characterizing Typha latifolia stands--their primary food source--and adherent sediments which may be consumed inadvertently while feeding. No evidence of site-influence or enhanced tissue metal levels was seen for Cu, Pb or Zn. While Cd : Ni accumulations were positively correlated in both the liver (r=0.78) and the kidneys (r=0.65), between-tissue comparisons indicated that hepatic : renal burdens were significantly correlated (r=0.75) only in the case of Ni. With the exception of 30-35% lower hepatic Zn levels in females relative to males within the Sudbury population, tissue metal levels did not vary according to sex or age class at either site. Our findings substantiate the potential of muskrat to serve as useful bioindicators/monitors of metal pollution in semi-aquatic environments. - Muskrats appear to be useful bioindicators of metal pollution in semi-aquatic environments.

Tissue metal levels in Muskrat (Ondatra zibethica) collected near the Sudbury (Ontario) ore-smelters; prospects for biomonitoring marsh pollution

International Nuclear Information System (INIS)

Parker, G.H.

2004-01-01

An examination of tissue metal levels in Sudbury-area muskrat (Ondatra zibethica) revealed that animals collected in the vicinity of the local ore-smelters contained elevated burdens of Cd and Ni in their liver and kidneys. Respective tissue concentrations averaged 2-fold and 3- to 6-fold higher than background values and are believed to reflect accumulations resulting from food chain contamination in regional marshes, including that reportedly characterizing Typha latifolia stands--their primary food source--and adherent sediments which may be consumed inadvertently while feeding. No evidence of site-influence or enhanced tissue metal levels was seen for Cu, Pb or Zn. While Cd : Ni accumulations were positively correlated in both the liver (r=0.78) and the kidneys (r=0.65), between-tissue comparisons indicated that hepatic : renal burdens were significantly correlated (r=0.75) only in the case of Ni. With the exception of 30-35% lower hepatic Zn levels in females relative to males within the Sudbury population, tissue metal levels did not vary according to sex or age class at either site. Our findings substantiate the potential of muskrat to serve as useful bioindicators/monitors of metal pollution in semi-aquatic environments. - Muskrats appear to be useful bioindicators of metal pollution in semi-aquatic environments

Lead in residential soil and dust in a mining and smelting district in northern Armenia: a pilot study

International Nuclear Information System (INIS)

Petrosyan, Varduhi; Orlova, Anna; Dunlap, Charles E.; Babayan, Emil; Farfel, Mark; Braun, Margrit von

2004-01-01

This pilot study of sources of lead exposure in residential settings was conducted in a mining and smelting district in northern Armenia. Samples of exterior soil and dust and interior house dust were collected in and around apartment buildings in Alaverdi where the country's largest polymetallic smelter is located, and in nearby mining towns of Aghtala and Shamlugh. The NITON XL-723 Multi-Element XRF analyzer was used for lead testing. Lead levels in samples from Alaverdi were higher than those in Shamlugh and Aghtala. In all three towns, the highest lead levels were found in loose exterior dust samples, and lead concentrations in yard soil were higher than those in garden soil. Many soil samples (34%) and the majority of loose dust samples (77%) in Alaverdi exceeded the US Environmental Protection Agency standard of 400 mg/kg for bare soil in children's play areas. In addition, 36% of floor dust samples from apartments in Alaverdi exceeded the US Environmental Protection Agency standard of 40 μg/ft 2 for lead loading in residential floor dust. The Armenian Ministry of Health and other interested agencies are being informed about the findings of the study so that they can consider and develop educational and preventive programs including blood lead screening among sensitive populations

Determination of Nuclear Track Parameters for LR-115 Detector by Using of MATLAB Software Technique

International Nuclear Information System (INIS)

AL-Jomaily, F.M.; AL-joburi, H.A.; Mheemeed, A.K.

2013-01-01

The nuclear track detector parameters, such as nuclear track diameter D(μm), number of track N T and area of track A T were determined by using MATLAB software technique for IR-115 detector irradiated by alpha particle from 241 Am source under 1.5, 2.5 and 3.5 MeV at etching time T B of 90, 120, 150 and 180 min.By using the image analysis of MATLAB software for nuclear track, the full width at half maximum FWHM and relative resolution R% were calculated for each energy of alpha particles.In this study, it was shown that increasing the alpha energy on the IR-115 detector leads to increased etching time T B and the dropping of R% to minimum value, and then reach a stable value before dropping at values 1.5, 2.5 MeV and unstable at 3.5 MeV. Imaging analysis by MATLAB technique which used in this study reflect good and accurate results for nuclear track detector parameters and we recommend using this technique for determination of these parameters

Evaluation of a video-based head motion tracking system for dedicated brain PET

Science.gov (United States)

Anishchenko, S.; Beylin, D.; Stepanov, P.; Stepanov, A.; Weinberg, I. N.; Schaeffer, S.; Zavarzin, V.; Shaposhnikov, D.; Smith, M. F.

2015-03-01

Unintentional head motion during Positron Emission Tomography (PET) data acquisition can degrade PET image quality and lead to artifacts. Poor patient compliance, head tremor, and coughing are examples of movement sources. Head motion due to patient non-compliance can be an issue with the rise of amyloid brain PET in dementia patients. To preserve PET image resolution and quantitative accuracy, head motion can be tracked and corrected in the image reconstruction algorithm. While fiducial markers can be used, a contactless approach is preferable. A video-based head motion tracking system for a dedicated portable brain PET scanner was developed. Four wide-angle cameras organized in two stereo pairs are used for capturing video of the patient's head during the PET data acquisition. Facial points are automatically tracked and used to determine the six degree of freedom head pose as a function of time. The presented work evaluated the newly designed tracking system using a head phantom and a moving American College of Radiology (ACR) phantom. The mean video-tracking error was 0.99±0.90 mm relative to the magnetic tracking device used as ground truth. Qualitative evaluation with the ACR phantom shows the advantage of the motion tracking application. The developed system is able to perform tracking with accuracy close to millimeter and can help to preserve resolution of brain PET images in presence of movements.

The isotopic composition of lead in man and the environment in Finland: isotope ratios of lead as indicators of pollutant source

International Nuclear Information System (INIS)

Keinonen, M.

1989-01-01

The isotopic composition of lead was determined in samples from the Helsinki area: in emission sources (gasoline, incinerator and lead smelter emissions, coal), in sources of intake to man (air, diet), in samples representing long-term deposition (lichen, soil, lake sediments) and in human tissue. The measurements of the isotope ratios 206 Pb/ 204 Pb and 206 Pb/ 207 Pb were done by thermal ionization mass spectrometry after chemical separation of lead by anion exchange and cathodic electrodeposition. The origin of lead in man and the environment in the Helsinki area was evaluated by using the differences in the measured isotope ratios as an indicator. The means of the ratios in gasoline ( 206 Pb/ 207 Pb 1.124+-0.026, 206 Pb/ 204 Pb 17.45+-0.42) and the ratios in other emission sources in Helsinki ( 206 Pb/ 207 Pb 1.149-1.226, 206 Pb/ 204 Pb 17.94-19.24) were significantly different. Lead in air samples from Helsinki (1.123+-0.013) could be attributed to gasoline, as lead in soil near a highway (1.136+-0.003). By contrast, isotope ratios measured in lichen (1.148+-0.006) indicated considerable amounts of lead from sources with higher 206 Pb abundances, evidently industrial sources. The isotope ratios in human liver, lung, and bone ( 206 Pb/ 207 Pb 1.142+-0.015, 1.151+-0.011, and 1.156+-0.013, respectively and 206 Pb/ 204 Pb 17.76+-0.28, 17.91+-0.20, and 17.96+-0.09, respectively) were practically the same and no significant dependence of the isotope ratios on age or concentration of lead was seen. In lake sediment cores a correlation was found between the isotope ratios, lead concentration, and depth. The non-anthropogenic lead of high isotope ratios from bedrock was the major component at depths dated older than 100 years. At the surface of the sediment atmospheric lead prevailed, with ratios similar to those of gasoline, air samples and lichen. In the post-1900 layers, anthropogenic lead made up about 40-60% of the total sedimentary lead

Processing of plastic track detectors

International Nuclear Information System (INIS)

Somogyi, G.

1977-01-01

A survey of some actual problems of the track processing methods available at this time for plastics is presented. In the case of the conventional chemical track-etching technique, mainly the etching situations related to detector geometry, and the relationship between registration sensitivity and the etching parameters are considered. Special attention is paid to the behaviour of track-revealing by means of electrochemical etching. Finally, some properties of a promising new track processing method based on graft polymerization are discussed. (author)

Processing of plastic track detectors

International Nuclear Information System (INIS)

Somogyi, G.

1976-01-01

A survey of some actual problems of the track processing methods available at this time for plastics is presented. In the case of the conventional chemical track etching technique mainly the etching situations related to detector geometry and the relationship of registration sensitivity and the etching parameters are considered. A special attention is paid to the behaviour of track revealing by means of electrochemical etching. Finally, some properties of a promising new track processing method based on graft polymerization is discussed. (orig.) [de

Sources of variation in concentrations of nickel and copper in mountain birch foliage near a nickel-copper smelter at Monchegorsk, north-western Russia: results of long-term monitoring

International Nuclear Information System (INIS)

Kozlov, Mikhail V.

2005-01-01

Concentrations of nickel and copper, two principal metal pollutants of the 'Severonikel' smelter at Monchegorsk, NW Russia, were measured in unwashed leaves of mountain birch, Betula pubescens subsp. czerepanovii, collected in eight study sites along the pollution gradient during 1991-2003. In spite of significant decline in metal emissions, concentrations of foliar metals in most of the study sites did not decrease, indicating that soil contamination remains extremely high. Multiyear mean values peaked at 6.6 km S of the smelter, where they were 20-25 times higher than in the most distant study site. Concentrations of both metals demonstrated pronounced annual variation, which was explained by the meteorological conditions of early summer: higher precipitation in May increased foliar concentrations of both metals, whereas higher precipitation in June resulted in lower foliar concentrations of nickel. These data suggest that ecotoxicological situation in metal-contaminated areas can be modified by the expected climate change. In heavily polluted sites individual birch trees generally retained their ranks in terms of metal contamination during 1995-2003, demonstrating that the use of the same set of trees can significantly increase the accuracy of the monitoring data. - Foliar concentrations of nickel and copper did not reflect emission decline during 1991-2003; annual variation was explained by weather conditions

EYE GAZE TRACKING

DEFF Research Database (Denmark)

2017-01-01

This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of: detecting the position of at least three reflections on said eye, transforming said positions to spanning...... a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation, detecting the position of said center of the eye relative to the position...... of said reflections and transforming this position to said normalized coordinate system, tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system. Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided...

Contaminated lead environments of man: reviewing the lead isotopic evidence in sediments, peat, and soils for the temporal and spatial patterns of atmospheric lead pollution in Sweden.

Science.gov (United States)

Bindler, Richard

2011-08-01

atmospherically deposited lead is ~2-5 g Pb m(-2) and ~1 g Pb m(-2) in the "pristine" north. Half of this cumulative total was deposited before industrialization. (4) In the vicinity of the Rönnskär smelter in northern Sweden, a major point source during the twentieth century, there is an isotopic pattern that deviates from the general trends elsewhere, reflecting the particular history of ore usage at Rönnskär, which further demonstrates the chronological record of lead loading recorded in peat and in soil mor horizons.

Persistent Aerial Tracking system for UAVs

KAUST Repository

Mueller, Matthias; Sharma, Gopal; Smith, Neil; Ghanem, Bernard

2016-01-01

In this paper, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by ‘handing over the camera’ from one UAV to another. We evaluate several state-of-the-art trackers on the VIVID aerial video dataset and additional sequences that are specifically tailored to low altitude UAV target tracking. Based on the evaluation, we select the leading tracker and improve upon it by optimizing for both speed and performance, integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

Persistent Aerial Tracking system for UAVs

KAUST Repository

Mueller, Matthias

2016-12-19

In this paper, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by ‘handing over the camera’ from one UAV to another. We evaluate several state-of-the-art trackers on the VIVID aerial video dataset and additional sequences that are specifically tailored to low altitude UAV target tracking. Based on the evaluation, we select the leading tracker and improve upon it by optimizing for both speed and performance, integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

Orthostatic intolerance during early mobilization after fast-track hip arthroplasty

DEFF Research Database (Denmark)

Jans, O; Bundgaard-Nielsen, M; Solgaard, S

2012-01-01

has not been established after THA. This study evaluated the cardiovascular response and tissue oxygenation to mobilization before and after surgery in relation to OI in fast-track THA patients. METHODS: /st>OI and the cardiovascular response to standing were evaluated with a standardized mobilization......BACKGROUND: /st>Early postoperative mobilization is a cornerstone in fast-track total hip arthroplasty (THA), but postoperative orthostatic intolerance (OI) may delay early recovery or lead to fainting, falls, and prosthesis dislocation or fracture. However, the prevalence and pathophysiology of OI...... protocol, before, 6, and 24 h after surgery in 26 patients undergoing THA with spinal anaesthesia and an opioid-sparing analgesic regime. Haemoglobin, fluid balance, and opioid use were recorded. Systolic (SAP) and diastolic (DAP) arterial pressure, heart rate (HR), stroke volume (SV), cardiac output (CO...

Lightning Jump Algorithm and Relation to Thunderstorm Cell Tracking, GLM Proxy and Other Meteorological Measurements

Science.gov (United States)

Schultz, Christopher J.; Carey, Lawrence D.; Cecil, Daniel J.; Bateman, Monte

2012-01-01

The lightning jump algorithm has a robust history in correlating upward trends in lightning to severe and hazardous weather occurrence. The algorithm uses the correlation between the physical principles that govern an updraft's ability to produce microphysical and kinematic conditions conducive for electrification and its role in the development of severe weather conditions. Recent work has demonstrated that the lightning jump algorithm concept holds significant promise in the operational realm, aiding in the identification of thunderstorms that have potential to produce severe or hazardous weather. However, a large amount of work still needs to be completed in spite of these positive results. The total lightning jump algorithm is not a stand-alone concept that can be used independent of other meteorological measurements, parameters, and techniques. For example, the algorithm is highly dependent upon thunderstorm tracking to build lightning histories on convective cells. Current tracking methods show that thunderstorm cell tracking is most reliable and cell histories are most accurate when radar information is incorporated with lightning data. In the absence of radar data, the cell tracking is a bit less reliable but the value added by the lightning information is much greater. For optimal application, the algorithm should be integrated with other measurements that assess storm scale properties (e.g., satellite, radar). Therefore, the recent focus of this research effort has been assessing the lightning jump's relation to thunderstorm tracking, meteorological parameters, and its potential uses in operational meteorology. Furthermore, the algorithm must be tailored for the optically-based GOES-R Geostationary Lightning Mapper (GLM), as what has been observed using Very High Frequency Lightning Mapping Array (VHF LMA) measurements will not exactly translate to what will be observed by GLM due to resolution and other instrument differences. Herein, we present some of

A solidification/stabilization process for wastewater treatment sludge from a primary copper smelter

Directory of Open Access Journals (Sweden)

Ivšić-Bajčeta Dragana

2013-01-01

Full Text Available Wastewater treatment sludge from primary copper smelter is characterized as hazardous waste that requires treatment prior disposal due to significant amount of heavy metals and arsenic. The aim of the presented study was to investigate the feasibility and the effectiveness of solidification/stabilization process of the sludge using fly ash and lime as binders. The effectiveness of the process was evaluated by Unconfined Compressive Strength (UCS testing, leaching tests (EN 12457-4 and Toxicity Characteristic Leaching Procedure (TCLP and Acid Neutralization Capacity (ANC test. All samples reached target UCS of 0.35 MPa. Calcium to silicon concentration ratio (cCa/cSi, determined by X-Ray Fluorescence (XRF analysis, was identified as main factor governing strength development. Inductively coupled plasma-optical emission spectrometry (ICP-OES analyses of solutions after leaching tests showed excellent stabilization of Cu, Ni, Pb and Zn (above 99 % and arsenic (above 90 % in samples with high Ca(OH2 content. Results of ANC test indicated that buffering capacity of solidified material linearly depended on Ca concentration in FA and lime. Sample with 20 % of binder heaving 50 % of FA and 50 % of lime met all requirements to be safely disposed. [Projekat Ministarstva nauke Republike Srbije, br. 34033

Visual tracking speed is related to basketball-specific measures of performance in NBA players.

Science.gov (United States)

Mangine, Gerald T; Hoffman, Jay R; Wells, Adam J; Gonzalez, Adam M; Rogowski, Joseph P; Townsend, Jeremy R; Jajtner, Adam R; Beyer, Kyle S; Bohner, Jonathan D; Pruna, Gabriel J; Fragala, Maren S; Stout, Jeffrey R

2014-09-01

The purpose of this study was to determine the relationship between visual tracking speed (VTS) and reaction time (RT) on basketball-specific measures of performance. Twelve professional basketball players were tested before the 2012-13 season. Visual tracking speed was obtained from 1 core session (20 trials) of the multiple object tracking test, whereas RT was measured by fixed- and variable-region choice reaction tests, using a light-based testing device. Performance in VTS and RT was compared with basketball-specific measures of performance (assists [AST]; turnovers [TO]; assist-to-turnover ratio [AST/TO]; steals [STL]) during the regular basketball season. All performance measures were reported per 100 minutes played. Performance differences between backcourt (guards; n = 5) and frontcourt (forward/centers; n = 7) positions were also examined. Relationships were most likely present between VTS and AST (r = 0.78; p basketball-specific performance measures. Backcourt players were most likely to outperform frontcourt players in AST and very likely to do so for VTS, TO, and AST/TO. In conclusion, VTS seems to be related to a basketball player's ability to see and respond to various stimuli on the basketball court that results in more positive plays as reflected by greater number of AST and STL and lower turnovers.

A mass spectrographic investigation of the methods for obtaining quantitative analyses for the mass balance of P and B through a submerged arc silicon smelter

International Nuclear Information System (INIS)

Rogers, D.E.C.; Jones, D.S.; Wegman, J.W.; Brain, L.; Van Wamelen, J.

1983-11-01

Mass spectrographic analyses of silica, silicon and silica reducing agents have been made using an arc discharge mass spectrograph. Analyses of certified standards and standard mixtures are given. An evaluation of doping techniques shows that the solid doping technique is satisfactory and that the liquid doping technique leads to significant errors. The amount of liquid dopant absorbed onto the substrate matrix varied from one compound to another and from one matrix to another. Comparison of analyses of solid-doped and undoped certified standards shows that all of the solid dopant is taken up by the sample. Analysis of silica reducing agents used in the arc reduction furnace shows that the major source of contamination by B and P is likely to be the coal and wood. Silica contains 0.4 ppm of B and 4 ppm of P and is a minor source of contamination. The levels in silicon are about 10 ppm for B and 20 ppm for P. A mass balance on P cannot be made and the missing amount is larger than the inaccuracy of the analysis. For analyses of feedstocks where the smelter outlet fumes are not sampled an accuracy of analysis to a factor of two is sufficient for the analysis of the coal and wood chips

Advanced Alignment of the ATLAS Tracking System

CERN Document Server

Butti, P; The ATLAS collaboration

2014-01-01

In order to reconstruct the trajectories of charged particles, the ATLAS experiment exploits a tracking system built using different technologies, planar silicon modules or microstrips (PIX and SCT detectors) and gaseous drift tubes (TRT), all embedded in a 2T solenoidal magnetic field. Misalignments and deformations of the active detector elements deteriorate the track reconstruction resolution and lead to systematic biases on the measured track parameters. The alignment procedures exploits various advanced tools and techniques in order to determine for module positions and correct for deformations. For the LHC Run II, the system is being upgraded with the installation of a new pixel layer, the Insertable B-layer (IBL).

Seasonal and circadian biases in bird tracking with solar GPS-tags

OpenAIRE

Silva, Rafa; Afán, Isabel; Gil, Juan A.; Bustamante, Javier

2017-01-01

Global Positioning System (GPS) tags are nowadays widely used in wildlife tracking. This geolocation technique can suffer from fix loss biases due to poor satellite GPS geometry, that result in tracking data gaps leading to wrong research conclusions. In addition, new solar-powered GPS tags deployed on birds can suffer from a new "battery drain bias" currently ignored in movement ecology analyses. We use a GPS tracking dataset of bearded vultures (Gypaetus barbatus), tracked for several years...

The use of advanced tracking technologies for the analysis of mobility in Alzheimer's disease and related cognitive diseases

Directory of Open Access Journals (Sweden)

Wahl Hans-Werner

2008-03-01

Full Text Available Abstract Background One of the more common behavioral manifestations of dementia-related disorders is severe problems with out-of-home mobility. Various efforts have been attempted to attain a better understanding of mobility behavior, but most studies are based on institutionalized patients and the assessment usually relies on reports of caregivers and institutional staff, using observational approaches, activity monitoring, or behavioral checklists. The current manuscript describes the research protocol of a project that measures mobility in Alzheimer's disease and related cognitive disorders in an innovative way, by taking advantage of advanced tracking technologies. Methods/design Participants are 360 demented persons, mildly cognitively impaired persons, and unimpaired controls aged ≥ 65 in Israel and Germany. Data regarding space-time activities will be collected via a GPS tracking kit for a period of 4 weeks in 3 waves (one year apart with the same participants (using a repeated measures design. Participants will be interviewed by use of a battery of instruments prior to and following GPS data collection. Further, a family member will complete a questionnaire both before and after data tracking. Statistical analyses will strive to explain differences in mobility based on a wide range of socio-structural, clinical, affect-related and environmental variables. We will also assess the impact of the use of advanced tracking technology on the quality of life of dementia patients and care givers, as well as its potential as a diagnostic tool. Systematic assessment of ethical issues involved in the use of tracking technology will be an integral component of the project. Discussion This project will be able to make a substantial contribution to basic as well as applied and clinical aspects in the area of mobility and cognitive impairment research. The innovative technologies applied in this study will allow for assessing a range of dimensions of

Risk assessment of metals and PAHs for receptor organisms in differently polluted areas in Slovenia.

Science.gov (United States)

Al Sayegh Petkovšek, Samar; Kopušar, Nataša; Tome, Davorin; Kryštufek, Boris

2015-11-01

Samples from receptor organisms (small mammals, passerine birds) and their food sources (herbaceous plants, leaves and fruits of wood plants, earthworms) were collected during 2011-2014 from the vicinity of a former lead smelter, from the vicinity of the largest Slovenian thermal power plant, from along a state road and also from a reference area. The samples were then analysed to determine the degree of contamination with the metals (Pb, Cd, Zn, Hg, Cu, Mo) and with polycyclic aromatic hydrocarbons (PAHs). This study provides the first data on metal and PAH exposure to small mammals and passerine birds in southeast Europe, focussing on the transfer of metals and PAHs through the food chain and on risk assessment for differently polluted areas in Slovenia. The results indicate that: (i) earthworms and herbaceous plants (especially roots) can be a source of metal exposure for organisms higher in the food chain; (ii) a risk from Pb and Cd (HQ > 1) in the vicinity of the former lead smelter exists for Myodes glareolus feeding in part on roots and for Apodemus flavicollis and Parus major feeding in part on earthworms; and (iii) mean Pb and Cd concentrations in the liver of small mammal species inhabiting the vicinity of the lead smelter reach effect concentrations in a significant proportion of the specimens (Pb: 40%, Cd: 67%); (iv) the results for P. major confirm that the study area is exposed to Pb, Cd, Hg; (v) metals contribute the major part of the total risk for receptor organisms from vicinity of lead smelter. On the contrary, the risk of PAHs for small mammals trapped close to the state road is insignificant. We can summarize, that the hazards experienced by the local ecosystem due to metal exposure may persist for decades in the vicinity of large emission sources (especially smelters). Copyright © 2015 Elsevier B.V. All rights reserved.

Dose-Response Relationship between Cumulative Occupational Lead Exposure and the Associated Health Damages: A 20-Year Cohort Study of a Smelter in China.

Science.gov (United States)

Wu, Yue; Gu, Jun-Ming; Huang, Yun; Duan, Yan-Ying; Huang, Rui-Xue; Hu, Jian-An

2016-03-16

Long-term airborne lead exposure, even below official occupational limits, has been found to cause lead poisoning at higher frequencies than expected, which suggests that China's existing occupational exposure limits should be reexamined. A retrospective cohort study was conducted on 1832 smelting workers from 1988 to 2008 in China. These were individuals who entered the plant and came into continuous contact with lead at work for longer than 3 months. The dose-response relationship between occupational cumulative lead exposure and lead poisoning, abnormal blood lead, urinary lead and erythrocyte zinc protoporphyrin (ZPP) were analyzed and the benchmark dose lower bound confidence limits (BMDLs) were calculated. Statistically significant positive correlations were found between cumulative lead dust and lead fumes exposures and workplace seniority, blood lead, urinary lead and ZPP values. A dose-response relationship was observed between cumulative lead dust or lead fumes exposure and lead poisoning (p lead dust and fumes doses were 0.68 mg-year/m³ and 0.30 mg-year/m³ for lead poisoning, respectively. The BMDLs of workplace airborne lead concentrations associated with lead poisoning were 0.02 mg/m³ and 0.01 mg/m³ for occupational exposure lead dust and lead fume, respectively. In conclusion, BMDLs for airborne lead were lower than occupational exposure limits, suggesting that the occupational lead exposure limits need re-examination and adjustment. Occupational cumulative exposure limits (OCELs) should be established to better prevent occupational lead poisoning.

Some hallways lead to other hallways and some lead to dead ends

OpenAIRE

Tam, Nancy Y.S

2013-01-01

Some Hallways Lead To Other Hallways And Some Lead To Dead Ends is a one-hour long synchronized audio tour for ten people. Listening to their assigned tracks played through headphones, the audience is mobilized through the SFU Woodward’s building. The aural content is comprised of choreographic instructions and my personal stories as a third culture kid in finding home. Appendix A is a research paper written for FPA 812, where I examine Henri Lefebvre’s ideas of space and how these ideas are ...

Quantitative diffusion tensor fiber tracking of age-related changes in the limbic system

International Nuclear Information System (INIS)

Stadlbauer, Andreas; Salomonowitz, Erich; Strunk, Guido; Hammen, Thilo; Ganslandt, Oliver

2008-01-01

Cerebral white matter is known to undergo degradation with aging, and diffusion tensor imaging (DTI) is capable of revealing the white matter integrity. We assessed age-related changes of quantitative diffusivity parameters and fiber characteristics within the fornix and the cingulum. Thirty-eight healthy subjects aged 18-88 years were examined at 3 Tesla using a 1.9-mm isotropic DTI sequence. Quantitative fiber tracking was performed for 3D-segmentation of the fornix and the cingulum to determine fractional anisotropy (FA), mean diffusivity (MD), eigenvalues (λ 1 , λ 2 , and λ 3 ), number of fibers (NoF), and mean NoF/voxel (FpV). In the fornix, all diffusivity parameters (FA, MD, and eigenvalues) were moderately correlated with age. Strong and moderate negative correlations for NoF and FpV were found, respectively. In the cingulum, no correlation was observed between FA and age, and only weak correlations for the other quantitative parameters. Differences in correlations between the fornix and the cingulum were significant for all diffusivity parameters and for NoF, but not for FpV. The strongest relative changes per decade of age were found in the fornix: FA -2.1%, MD 4.2%, NoF -10.6%, and FpV -4.6%. Our quantitative 3D fiber tracking approach shows that the cingulum is resistant to aging while the fornix is not. (orig.)

Development of a Hough transformation track finder for time projection chambers

International Nuclear Information System (INIS)

Heinze, Isa

2013-12-01

The International Linear Collider (ILC) is a planned particle physics experiment. One of the two detector concepts is the International Large Detector (ILD) concept for which a time projection chamber is foreseen as the main tracking device. In the ILD the particle flow concept is followed which leads to special requirements for the detector. Especially for the tracking system a very good momentum resolution is required. Several prototypes were build to prove that it is possible to build a TPC which fulfills the requirements for a TPC in the ILD. One is the Large Prototype with which different readout technologies currently under development are tested. In parallel reconstruction software is developed for the reconstruction of Large Prototype data. In this thesis the development of a track finding algorithm based on the Hough transformation is described. It can find curved tracks (with magnetic field) as well as straight tracks (without magnetic field). This package was mainly developed for Large Prototype testbeam data but was also tested on Monte Carlo simulation of tracks in the ILD TPC. Furthermore the analysis of testbeam data regarding the single point resolution is presented. The data were taken with the Large Prototype and a readout module with GEM (gas electron multiplier) amplification. For the reconstruction of these data the software package mentioned above was used. The single point resolution is directly related to the momentum resolution of the detector, thus a good single point resolution is needed to achieve a good momentum resolution.

Development of a Hough transformation track finder for time projection chambers

Energy Technology Data Exchange (ETDEWEB)

Heinze, Isa

2013-12-15

The International Linear Collider (ILC) is a planned particle physics experiment. One of the two detector concepts is the International Large Detector (ILD) concept for which a time projection chamber is foreseen as the main tracking device. In the ILD the particle flow concept is followed which leads to special requirements for the detector. Especially for the tracking system a very good momentum resolution is required. Several prototypes were build to prove that it is possible to build a TPC which fulfills the requirements for a TPC in the ILD. One is the Large Prototype with which different readout technologies currently under development are tested. In parallel reconstruction software is developed for the reconstruction of Large Prototype data. In this thesis the development of a track finding algorithm based on the Hough transformation is described. It can find curved tracks (with magnetic field) as well as straight tracks (without magnetic field). This package was mainly developed for Large Prototype testbeam data but was also tested on Monte Carlo simulation of tracks in the ILD TPC. Furthermore the analysis of testbeam data regarding the single point resolution is presented. The data were taken with the Large Prototype and a readout module with GEM (gas electron multiplier) amplification. For the reconstruction of these data the software package mentioned above was used. The single point resolution is directly related to the momentum resolution of the detector, thus a good single point resolution is needed to achieve a good momentum resolution.

Lead exposure from lead pellets: age-related accumulation in mute swans

Energy Technology Data Exchange (ETDEWEB)

Eskildsen, J.; Grandjean, P.

1984-05-01

In a cross-sectional study of adult swans and their successfully fledged young in Ringkobing Fjord, West Jutland, Denmark, 128 venous blood samples were taken during the moulting period and analyzed for lead. While the juveniles generally showed blood lead levels below 15 micrograms/100 ml (median, 11 micrograms/100 ml), the values were significantly higher in adults (median, 25 micrograms/100 ml). Adult females showed slightly higher levels than did adult males. None of the birds examined showed signs of acute lead toxicity, and increased blood levels in adults may reflect increased lead body burdens from previous ingestion of lead shot as gizzard stones.

A Data Warehouse Solution for Analyzing RFID-Based Baggage Tracking Data

DEFF Research Database (Denmark)

Ahmed, Tanvir; Pedersen, Torben Bach; Lu, Hua

2013-01-01

spatio-temporal Radio Frequency Identification (RFID) baggage tracking data. Analysis of this data can yield interesting results on baggage flow, the causes of baggage mishandling, and the parties responsible for the mishandling(airline, airport, handler,...), which can ultimately lead to improved...... with the appropriate tracking data from the data sources. The presented concepts are generalizable to other types of multi-site indoor tracking systems based on Bluetooth and RFID. The system has been tested with large amount of real-world RFID-based baggage tracking data from a major industry initiative...

Graph Model Based Indoor Tracking

DEFF Research Database (Denmark)

Jensen, Christian Søndergaard; Lu, Hua; Yang, Bin

2009-01-01

The tracking of the locations of moving objects in large indoor spaces is important, as it enables a range of applications related to, e.g., security and indoor navigation and guidance. This paper presents a graph model based approach to indoor tracking that offers a uniform data management...

Childhood lead poisoning data for California by county, age, and blood lead level for the years 2007-2009; and age of housing data for 2000.

Data.gov (United States)

California Environmental Health Tracking Program — This dataset contains counts and percentages of blood lead levels among children tested for lead poisoning during 2007-2009 within California . The data are...

Size-resolved dust and aerosol contaminants associated with copper and lead smelting emissions: Implications for emission management and human health

Energy Technology Data Exchange (ETDEWEB)

Csavina, Janae [Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Taylor, Mark P. [Environmental Science, Faculty of Science, Macquarie University, North Ryde, Sydney, NSW 2109 (Australia); Félix, Omar [Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Rine, Kyle P. [Department of Atmospheric Sciences, The University of Arizona, Tucson, AZ 85721 (United States); Eduardo Sáez, A., E-mail: esaez@email.arizona.edu [Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 (United States); Betterton, Eric A., E-mail: betterton@atmo.arizona.edu [Department of Atmospheric Sciences, The University of Arizona, Tucson, AZ 85721 (United States)

2014-09-15

Mining operations, including crushing, grinding, smelting, refining, and tailings management, are a significant source of airborne metal and metalloid contaminants such as As, Pb and other potentially toxic elements. In this work, we show that size-resolved concentrations of As and Pb generally follow a bimodal distribution with the majority of contaminants in the fine size fraction (< 1 μm) around mining activities that include smelting operations at various sites in Australia and Arizona. This evidence suggests that contaminated fine particles (< 1 μm) are the result of vapor condensation and coagulation from smelting operations while coarse particles are most likely the result of windblown dust from contaminated mine tailings and fugitive emissions from crushing and grinding activities. These results on the size distribution of contaminants around mining operations are reported to demonstrate the ubiquitous nature of this phenomenon so that more effective emission management and practices that minimize health risks associated with metal extraction and processing can be developed. - Highlights: • Lead and copper smelting produce significant atmospheric concentrations of lead and arsenic. • Atmospheric lead and arsenic concentrations depend on particle size. • Lead isotopic analysis can be used to assess source of atmospheric contamination from smelters.

Combining Stereo SECCHI COR2 and HI1 Images for Automatic CME Front Edge Tracking

Science.gov (United States)

Kirnosov, Vladimir; Chang, Lin-Ching; Pulkkinen, Antti

2016-01-01

COR2 coronagraph images are the most commonly used data for coronal mass ejection (CME) analysis among the various types of data provided by the STEREO (Solar Terrestrial Relations Observatory) SECCHI (Sun-Earth Connection Coronal and Heliospheric Investigation) suite of instruments. The field of view (FOV) in COR2 images covers 215 solar radii (Rs) that allow for tracking the front edge of a CME in its initial stage to forecast the lead-time of a CME and its chances of reaching the Earth. However, estimating the lead-time of a CME using COR2 images gives a larger lead-time, which may be associated with greater uncertainty. To reduce this uncertainty, CME front edge tracking should be continued beyond the FOV of COR2 images. Therefore, heliospheric imager (HI1) data that covers 1590 Rs FOV must be included. In this paper, we propose a novel automatic method that takes both COR2 and HI1 images into account and combine the results to track the front edges of a CME continuously. The method consists of two modules: pre-processing and tracking. The pre-processing module produces a set of segmented images, which contain the signature of a CME, for both COR2 and HI1 separately. In addition, the HI1 images are resized and padded, so that the center of the Sun is the central coordinate of the resized HI1 images. The resulting COR2 andHI1 image set is then fed into the tracking module to estimate the position angle (PA) and track the front edge of a CME. The detected front edge is then used to produce a height-time profile that is used to estimate the speed of a CME. The method was validated using 15 CME events observed in the period from January 1, 2008 to August 31, 2009. The results demonstrate that the proposed method is effective for CME front edge tracking in both COR2 and HI1 images. Using this method, the CME front edge can now be tracked automatically and continuously in a much larger range, i.e., from 2 to 90 Rs, for the first time. These improvement scan greatly

Local Fields in Human Subthalamic Nucleus Track the Lead-up to Impulsive Choices

Directory of Open Access Journals (Sweden)

John M. Pearson

2017-11-01

Full Text Available The ability to adaptively minimize not only motor but cognitive symptoms of neurological diseases, such as Parkinson's Disease (PD and obsessive-compulsive disorder (OCD, is a primary goal of next-generation deep brain stimulation (DBS devices. On the basis of studies demonstrating a link between beta-band synchronization and severity of motor symptoms in PD, the minimization of beta band activity has been proposed as a potential training target for closed-loop DBS. At present, no comparable signal is known for the impulsive side effects of PD, though multiple studies have implicated theta band activity within the subthalamic nucleus (STN, the site of DBS treatment, in processes of conflict monitoring and countermanding. Here, we address this challenge by recording from multiple independent channels within the STN in a self-paced decision task to test whether these signals carry information sufficient to predict stopping behavior on a trial-by-trial basis. As in previous studies, we found that local field potentials (LFPs exhibited modulations preceding self-initiated movements, with power ramping across multiple frequencies during the deliberation period. In addition, signals showed phasic changes in power around the time of decision. However, a prospective model that attempted to use these signals to predict decision times showed effects of risk level did not improve with the addition of LFPs as regressors. These findings suggest information tracking the lead-up to impulsive choices is distributed across multiple frequency scales in STN, though current techniques may not possess sufficient signal-to-noise ratios to predict—and thus curb—impulsive behavior on a moment-to-moment basis.

Motion Tracking for Medical Imaging: A Non-Visible Structured Light Tracking Approach

DEFF Research Database (Denmark)

Olesen, Oline Vinter; Paulsen, Rasmus Reinhold; Højgaard, Liselotte

2012-01-01

We present a system for head motion tracking in 3D brain imaging. The system is based on facial surface reconstruction and tracking using a structured light (SL) scanning principle. The system is designed to fit into narrow 3D medical scanner geometries limiting the field of view. It is tested......, is that it is not necessary to place markers on the patient. This provides a simpler workflow and eliminates uncertainties related to marker attachment and stability. We show proof of concept of a marker less tracking system especially designed for clinical use with promising results....... in a clinical setting on the high resolution research tomograph (HRRT), Siemens PET scanner with a head phantom and volunteers. The SL system is compared to a commercial optical tracking system, the Polaris Vicra system, from NDI based on translatory and rotary ground truth motions of the head phantom...

Distribution of lead in teeth

Energy Technology Data Exchange (ETDEWEB)

Fremlin, J H; Tanti-Wipawin, W [Birmingham Univ. (UK). Dept. of Physics

1976-07-01

There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an ..cap alpha.. emitter, half-life 8 d. These ..cap alpha.. particles can be recorded by a plastic solid-state track detector.

Distribution of lead in teeth

International Nuclear Information System (INIS)

Fremlin, J.H.; Tanti-Wipawin, W.

1976-01-01

There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an α emitter, half-life 8 d. These α particles can be recorded by a plastic solid-state track detector. (U.K.)

Contamination of the O2 soil horizon by zinc smelting and its effect on woodlouse survival

Science.gov (United States)

Beyer, W.N.; Miller, G.W.; Cromartie, E.J.

1984-01-01

Samples of litter from the 02 horizon of Dekalb soil (loamyskeletal, mixed, mesic Typic Dystrochrept) were collected from 18 ridgetop sites on a transect that ran by two Zn smelters in Palmerton, Pa. Metal concentrations increased by regular gradations from a minimum at a site 105 km west of the smelters (67 mg/kg Zn, 0.85 mg/kg Cd, 150 mg/kg Pb, 11 mg/kg Cu) to a maximum 1.2 km east of the smelters (35,000 mg/kg Zn, 1300 mg/kg Cd, 3200 mg/kg Pb, 280 mg/kg Cu), and then decreased until they reached an eastern minimum at the easternmost site, 19 km from the smelters. An increase in the P concentrations near the smelters showed that the emissions were disrupting nutrient flow through the ecosystem. An increase in the pH near the smelters was attributed to the high concentrations of Zn. The log of the distance of the sites from the smelters was significantly correlated (r = - 0.80, p Zinc, cadmium, lead, copper, and sulfur were experimentally added, alone or in combination, to 02 litter collected far from any known source of metal emissions. The highest concentration of Zn added (20,000 mg/kg) was toxic enough to account for the mortality observed in the earlier test. A lower concentration of Zn (5000 mg/kg) as well as the concentration of Cd (500 mg/kg) tested also significantly (p < 0.05) increased the mortality of woodlice.

Impact of a lead mining-smelting complex on the forest-floor litter arthropod fauna in the new lead belt region of southeast Missouri

Energy Technology Data Exchange (ETDEWEB)

Watson, A.P.; Van Hook, R.I.; Jackson, D.R.; Reichle, D.E.

1976-07-01

Studies of biological activity within the litter horizons of a watershed contaminated by emissions from a lead-ore processing complex focused on the litter-arthropod food chain as a means of detecting perturbations in a heavy-metal contaminated ecosystem. Both point sources (smelter stack emissions) and fugitive sources (ore-handling processes, yard dusts, and exposed concentrate piles) contributed to the Pb, Zn, Cu, and Cd levels in the study area. Arthropod trophic level density, biomass, and heavy metal content were determined by analysis of specimens removed from litter by von Tullgren funnel extraction, taxonomically classified, and segregated into the trophic categories. Changes in litter decomposition were reflected in the dynamics of the litter arthropod community. Food-chain dilution of Pb, Zn, Cu, and Cd from litter to litter consumer was occurring, as indicated by the mean concentration factors. Accumulation of Pb by litter consumers was much less than that found for the other three heavy metals. In contrast, predatory arthropods on Crooked Creek Watershed either concentrated or equilibrated with respect to Pb, Zn, and Cd from their prey, as indicated by mean total predator concentration factors. A significant depression of the Ca, Mg, and K content litter occurred relative to the control within 0.8 km of the stack. Two mechanisms were postulated to explain this result: increased leaching of cations through the litter induced by a loss of cation exchange capacity, a decrease in pH, and a decrease in microbial immobilization of macronutrients; and a decreased uptake of macronutrients due to root damage produced by heavy-metal concentrations.

A comparison of visual and kinesthetic-tactual displays for compensatory tracking

Science.gov (United States)

Jagacinski, R. J.; Flach, J. M.; Gilson, R. D.

1983-01-01

Recent research on manual tracking with a kinesthetic-tactual (KT) display suggests that under certain conditions it can be an effective alternative or supplement to visual displays. In order to understand better how KT tracking compares with visual tracking, both a critical tracking and stationary single-axis tracking tasks were conducted with and without velocity quickening. In the critical tracking task, the visual displays were superior, however, the quickened KT display was approximately equal to the unquickened visual display. In stationary tracking tasks, subjects adopted lag equalization with the quickened KT and visual displays, and mean-squared error scores were approximately equal. With the unquickened displays, subjects adopted lag-lead equalization, and the visual displays were superior. This superiority was partly due to the servomotor lag in the implementation of the KT display and partly due to modality differences.

COMBINING INDEPENDENT VISUALIZATION AND TRACKING SYSTEMS FOR AUGMENTED REALITY

Directory of Open Access Journals (Sweden)

P. Hübner

2018-05-01

Full Text Available The basic requirement for the successful deployment of a mobile augmented reality application is a reliable tracking system with high accuracy. Recently, a helmet-based inside-out tracking system which meets this demand has been proposed for self-localization in buildings. To realize an augmented reality application based on this tracking system, a display has to be added for visualization purposes. Therefore, the relative pose of this visualization platform with respect to the helmet has to be tracked. In the case of hand-held visualization platforms like smartphones or tablets, this can be achieved by means of image-based tracking methods like marker-based or model-based tracking. In this paper, we present two marker-based methods for tracking the relative pose between the helmet-based tracking system and a tablet-based visualization system. Both methods were implemented and comparatively evaluated in terms of tracking accuracy. Our results show that mobile inside-out tracking systems without integrated displays can easily be supplemented with a hand-held tablet as visualization device for augmented reality purposes.

Transmission electron microscopy porometry of track membranes

International Nuclear Information System (INIS)

Reutov, V.F.; Dmitriev, S.N.; Sokhatskij, A.S.; Akap'ev, G.N.

1998-01-01

A fast method has been developed for the preparation of a sample appropriate for both SEM and TEM porometry of track membranes with pore channels of various geometric profiles and of size 10 nm and above. The method leads to the electrochemical deposition in the pore channels of a precipitate of monocrystalline copper directly on the surface of a copper foil disk bent into a spherical shape. The tight clamping of the track membrane on the disk surface is carried out by the creation of a vacuum in the space between them

Effect of track etch rate on geometric track characteristics for polymeric track detectors

International Nuclear Information System (INIS)

Abdel-Naby, A.A.; El-Akkad, F.A.

2001-01-01

Analysis of the variable track etch rate on geometric track characteristic for polymeric track detectors has been applied to the case of LR-155 II SSNTD. Spectrometric characteristics of low energy alpha particles response by the polymeric detector have been obtained. The track etching kinematics theory of development of minor diameter of the etched tracks has been applied. The calculations show that, for this type of detector, the energy dependence of the minor track diameter d is linear for small-etched removal layer h. The energy resolution gets better for higher etched removal layer

Effect of fast-track cardiac anesthesia on myocardial oxidative damage, inflammation and nerve related peptides of patients undergoing cardiac operation

Directory of Open Access Journals (Sweden)

Xing-Tao Cai

2016-01-01

Full Text Available Objective: To study the effect of fast-track cardiac anesthesia on myocardial oxidative damage, inflammation and nerve related peptides of patients undergoing cardiac operation. Methods: Sixty patients with rheumatic heart disease undergoing heart valve surgery were randomly divided into the fast track group (n=30 and conventional group (n=30. Then myocardial injury indicators, mitochondrial oxidative stress indicators, inflammation indicators and nerverelated peptides of both groups were analyzed. Results: cTnI contents at T2-T4 points in time of both groups showed an increasing trend and the increasing trend of fast track group was weaker than that of conventional group; SOD contents as well as mitochondrial tristate respiratory function, respiratory control ratios and phosphorus oxygen ratios in myocardial tissue of fast track group were higher than those of conventional group, and MDA contents was lower than those of conventional group; plasma TNF-α, IL-6, IL-8, NSE, S100β and Aβ contents of fast track group were lower than those of conventional group. Conclusions: Fasttrack cardiac anesthesia can protect myocardial cells, reduce mitochondrial oxidative stress, relieve inflammation and improve nerve function; it is an ideal anesthesia method for cardiac operation.

Magnetoresistance sensitivity mapping of the localized response of contiguous and lead-overlaid sensors

International Nuclear Information System (INIS)

Sankar, Sandra

2003-01-01

Magnetoresistance sensitivity mapping (MSM) was used to investigate the local response of magnetic recording sensors without convolution of the writer, magnetic media and data channel. From a 2D map of the local sensor response, the intrinsic pulse shape and magnetic track profile are readily obtained. Pulse-width is a concern for high data rate since if pulse-width is too broad, individual transitions become difficult to distinguish. Track profiles are important because due to the small difference between magnetic write-width and magnetic read-width, side reading will lead to an increase in noise. Three experiments are discussed: the dependence of the pulse-width (PW50) of the standard contiguous junction (CJ) design on shield-to-shield spacing; a comparison of the pulse shape of lead-overlaid (LOL) and CJ designs; and a comparison of the magnetic track profile (including track-width and skirt ratio) of LOL and CJ designs. The LOL design offers an increased sensitivity; however, as seen from MSM, the penalties are broadening of the track and pulse profiles. These are a direct result of the finite current in the lead overlay region and an increased shield-to-shield spacing in that region. The MSM image shows a curvature, which is associated with the topography of the top shield due to the lead overlay

ACTS: from ATLAS software towards a common track reconstruction software

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00349786; The ATLAS collaboration; Salzburger, Andreas; Kiehn, Moritz; Hrdinka, Julia; Calace, Noemi

2017-01-01

Reconstruction of charged particles' trajectories is a crucial task for most particle physics experiments. The high instantaneous luminosity achieved at the LHC leads to a high number of proton-proton collisions per bunch crossing, which has put the track reconstruction software of the LHC experiments through a thorough test. Preserving track reconstruction performance under increasingly difficult experimental conditions, while keeping the usage of computational resources at a reasonable level, is an inherent problem for many HEP experiments. Exploiting concurrent algorithms and using multivariate techniques for track identification are the primary strategies to achieve that goal. Starting from current ATLAS software, the ACTS project aims to encapsulate track reconstruction software into a generic, framework- and experiment-independent software package. It provides a set of high-level algorithms and data structures for performing track reconstruction tasks as well as fast track simulation. The software is de...

Study of the contamination of forages and legumes by lead and heavy metals

Energy Technology Data Exchange (ETDEWEB)

Delcarte, E; Impens, R; Kirchmann, R; Nangniot, P; Fagniart, E

1975-01-01

A description of the methods used by the authors for their study of contamination of the environment and of the food chain by heavy metals is presented with particular reference to lead, cadmium and zinc. The first phase consists of taking samples, in industrial and urban areas and in the vicinity of highways, of soil and various common plants, including Plantago major L. (greater plantain), Ligustrum sp. (privet), Trifolium repens L. (white clover) and Tussilago farfara L. (coltsfoot). Concentrations of metal substances in these samples are measured by means of oscillopolarography at a set voltage. Risk areas are thus demarcated where fodder, vegetable and fruit samples are taken regularly throughout the vegetation period. A watch is kept on the progress and extent of Zn, Cd, Pb, Ni, Co and Cu fall-out in vegetable gardens and orchards in the vicinity of smelters in the Meuse valley. The results are compared with those obtained in the suburbs of Brussels near highway intersections and in a control area, away from any source of pollution. These results reveal that there is a serious risk of chronic poisoning in human beings and animals which feed on contaminated plants. Parallel laboratory tests are being carried out on the absorption, retention and toxicity of these metal substances in plants. The results obtained using stable lead and /sup 210/lead in Zea mays L. (maize) are discussed. Finally, dairy cattle are being experimentally fed on fodder which has been artificially enriched with stable lead and /sup 210/lead. The aim is to calculate the rate of alimentary lead transfer to the milk, urine and feces.

Satellite and acoustic tracking device

KAUST Repository

Berumen, Michael L.

2014-02-20

The present invention relates a method and device for tracking movements of marine animals or objects in large bodies of water and across significant distances. The method and device can track an acoustic transmitter attached to an animal or object beneath the ocean surface by employing an unmanned surface vessel equipped with a hydrophone array and GPS receiver.

Satellite and acoustic tracking device

KAUST Repository

Berumen, Michael L.; De la Torre, Pedro

2014-01-01

The present invention relates a method and device for tracking movements of marine animals or objects in large bodies of water and across significant distances. The method and device can track an acoustic transmitter attached to an animal or object beneath the ocean surface by employing an unmanned surface vessel equipped with a hydrophone array and GPS receiver.

Underwater Acoustic Target Tracking: A Review

Science.gov (United States)

Han, Ying; Fan, Liying

2018-01-01

Advances in acoustic technology and instrumentation now make it possible to explore marine resources. As a significant component of ocean exploration, underwater acoustic target tracking has aroused wide attention both in military and civil fields. Due to the complexity of the marine environment, numerous techniques have been proposed to obtain better tracking performance. In this paper, we survey over 100 papers ranging from innovative papers to the state-of-the-art in this field to present underwater tracking technologies. Not only the related knowledge of acoustic tracking instrument and tracking progress is clarified in detail, but also a novel taxonomy method is proposed. In this paper, algorithms for underwater acoustic target tracking are classified based on the methods used as: (1) instrument-assisted methods; (2) mode-based methods; (3) tracking optimization methods. These algorithms are compared and analyzed in the aspect of dimensions, numbers, and maneuvering of the tracking target, which is different from other survey papers. Meanwhile, challenges, countermeasures, and lessons learned are illustrated in this paper. PMID:29301318

Exploiting target amplitude information to improve multi-target tracking

Science.gov (United States)

Ehrman, Lisa M.; Blair, W. Dale

2006-05-01

Closely-spaced (but resolved) targets pose a challenge for measurement-to-track data association algorithms. Since the Mahalanobis distances between measurements collected on closely-spaced targets and tracks are similar, several elements of the corresponding kinematic measurement-to-track cost matrix are also similar. Lacking any other information on which to base assignments, it is not surprising that data association algorithms make mistakes. One ad hoc approach for mitigating this problem is to multiply the kinematic measurement-to-track likelihoods by amplitude likelihoods. However, this can actually be detrimental to the measurement-to-track association process. With that in mind, this paper pursues a rigorous treatment of the hypothesis probabilities for kinematic measurements and features. Three simple scenarios are used to demonstrate the impact of basing data association decisions on these hypothesis probabilities for Rayleigh, fixed-amplitude, and Rician targets. The first scenario assumes that the tracker carries two tracks but only one measurement is collected. This provides insight into more complex scenarios in which there are fewer measurements than tracks. The second scenario includes two measurements and one track. This extends naturally to the case with more measurements than tracks. Two measurements and two tracks are present in the third scenario, which provides insight into the performance of this method when the number of measurements equals the number of tracks. In all cases, basing data association decisions on the hypothesis probabilities leads to good results.

Latent tracks in polymeric etched track detectors

International Nuclear Information System (INIS)

Yamauchi, Tomoya

2013-01-01

Track registration properties in polymeric track detectors, including Poly(allyl diglycol carbonate), Bispenol A polycarbonate, Poly(ethylen terephtarate), and Polyimide, have been investigated by means of Fourie transform Infararede FT-IR spectrometry. Chemical criterion on the track formation threshold has been proposes, in stead of the conventional physical track registration models. (author)

Quality of Slab Track Construction - Track Alignment Design and Track Geometry

Science.gov (United States)

Šestáková, Janka

2015-05-01

The slab track superstructure design (without ballast) is a perspective construction especially for building tunnels and bridges in the modernized sections of railway tracks in Slovakia. Monitoring of the structure described in this article is focused on the transition areas between standard structure with ballast and slab track construction.

Tracking the formation of methylammonium lead triiodide perovskite

International Nuclear Information System (INIS)

Liu, Lijia; McLeod, John A.; Wang, Rongbin; Shen, Pengfei; Duhm, Steffen

2015-01-01

The formation mechanism of perovskite methylammonium lead triiodide (CH 3 NH 3 PbI 3 ) was studied with in situ X-ray photoelectron spectroscopy (XPS) on successive depositions of thermally evaporated methylammonium iodide (CH 3 NH 3 I) on a lead iodide (PbI 2 ) film. This deposition method mimics the “two-step” synthesis method commonly used in device fabrication. We find that several competing processes occur during the formation of perovskite CH 3 NH 3 PbI 3 . Our most important finding is that during vapour deposition of CH 3 NH 3 I onto PbI 2 , at least two carbon species are present in the resulting material, while only one nitrogen species is present. This suggests that CH 3 NH 3 I can dissociate during the transition to a perovskite phase, and some of the resulting molecules can be incorporated into the perovskite. The effect of partial CH 3 NH 3 substitution with CH 3 was evaluated, and electronic structure calculations show that CH 3 defects would impact the photovoltaic performance in perovskite solar cells. The possibility that not all A sites in the APbI 3 perovskite are occupied by CH 3 NH 3 is therefore an important consideration when evaluating the performance of organometallic trihalide solar cells synthesized using typical approaches

Faster, higher, stronger, older: Relative age effects are most influential during the youngest age grade of track and field athletics in the United Kingdom.

Science.gov (United States)

Kearney, Philip E; Hayes, Philip R; Nevill, Alan

2018-03-07

The relative age effect (RAE) is a common phenomenon in youth sport, whereby children born early in the selection year are more likely to experience success and to sustain participation. There is a lack of research investigating variables which influence RAEs within track and field athletics. Such information is vital to guide policies in relation to competition structure, youth development squads and coach education. A database of competition results was analysed to determine the extent to which RAEs were present in track and field athletics in the United Kingdom. Subsequent analyses examined whether age, sex, event and skill level influenced the RAE. Examination of 77,571 records revealed that RAEs were widespread, but most pronounced during Under 13 (U13) competitions; that is, during athletes' first exposure to formal track and field competition. Sex, event and skill level further influenced the existence and magnitude of RAEs at different age grades. Relative age is a key influencing factor within track and field athletics, especially at the youngest age category. Consequently, national governing bodies need to consider what administrative and stakeholder initiatives are necessary to minimise the effects of RAEs on young athletes' early experiences of competition.

How visual search relates to visual diagnostic performance : a narrative systematic review of eye-tracking research in radiology

NARCIS (Netherlands)

van der Gijp, A; Ravesloot, C J; Jarodzka, H; van der Schaaf, M F; van der Schaaf, I C; van Schaik, J P J; ten Cate, Olle

Eye tracking research has been conducted for decades to gain understanding of visual diagnosis such as in radiology. For educational purposes, it is important to identify visual search patterns that are related to high perceptual performance and to identify effective teaching strategies. This review

Effect of task-related continuous auditory feedback during learning of tracking motion exercises

Directory of Open Access Journals (Sweden)

Rosati Giulio

2012-10-01

Full Text Available Abstract Background This paper presents the results of a set of experiments in which we used continuous auditory feedback to augment motor training exercises. This feedback modality is mostly underexploited in current robotic rehabilitation systems, which usually implement only very basic auditory interfaces. Our hypothesis is that properly designed continuous auditory feedback could be used to represent temporal and spatial information that could in turn, improve performance and motor learning. Methods We implemented three different experiments on healthy subjects, who were asked to track a target on a screen by moving an input device (controller with their hand. Different visual and auditory feedback modalities were envisaged. The first experiment investigated whether continuous task-related auditory feedback can help improve performance to a greater extent than error-related audio feedback, or visual feedback alone. In the second experiment we used sensory substitution to compare different types of auditory feedback with equivalent visual feedback, in order to find out whether mapping the same information on a different sensory channel (the visual channel yielded comparable effects with those gained in the first experiment. The final experiment applied a continuously changing visuomotor transformation between the controller and the screen and mapped kinematic information, computed in either coordinate system (controller or video, to the audio channel, in order to investigate which information was more relevant to the user. Results Task-related audio feedback significantly improved performance with respect to visual feedback alone, whilst error-related feedback did not. Secondly, performance in audio tasks was significantly better with respect to the equivalent sensory-substituted visual tasks. Finally, with respect to visual feedback alone, video-task-related sound feedback decreased the tracking error during the learning of a novel

Statistical fluctuations in heavy-charged-particle tracks

International Nuclear Information System (INIS)

Hamm, R.N.; Turner, J.E.; Wright, H.A.

1985-01-01

We present the results of the following Monte Carlo track-segment calculations for protons with energies of 1, 2, 5, and 10 MeV in liquid water: (1) radial dose around a long segment of a proton track; (2) energy-loss straggling distributions for protons of different energies in 1 μm of water; (3) the distribution in the average absorbed dose around track segments of various lengths; (4) the relative standard deviations in these distributions as functions of the length of the track segments. Calculations such as those presented here are useful for studying track phenomena on a microdosimetric scale, where statistical fluctuations are substantial

Thinking Tracks for Multidisciplinary System Design

Directory of Open Access Journals (Sweden)

Gerrit Maarten Bonnema

2016-11-01

Full Text Available Systems engineering is, for a large part, a process description of how to bring new systems to existence. It is valuable as it directs the development effort. Tools exist that can be used in this process. System analysis investigates existing and/or desired situations. However, how to create a system that instantiates the desired situation depends significantly on human creativity and insight; the required human trait here is commonly called systems thinking. In literature, this trait is regularly used, but information on how to do systems thinking is scarce. Therefore, we have introduced earlier twelve thinking tracks that are concrete and help system designers to make an optimal fit between the system under design, the identified issue, the user, the environment and the rest of the world. The paper provides the scientific rationale for the thinking tracks based on literature. Secondly, the paper presents three cases of application, leading to the conclusion that the tracks are usable and effective.

Tracking the formation of methylammonium lead triiodide perovskite

Energy Technology Data Exchange (ETDEWEB)

Liu, Lijia, E-mail: ljliu@suda.edu.cn, E-mail: jmcleod@suda.edu.cn; McLeod, John A., E-mail: ljliu@suda.edu.cn, E-mail: jmcleod@suda.edu.cn; Wang, Rongbin; Shen, Pengfei; Duhm, Steffen [Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, 199 Ren' ai Road, Suzhou, Jiangsu 215123 (China)

2015-08-10

The formation mechanism of perovskite methylammonium lead triiodide (CH{sub 3}NH{sub 3}PbI{sub 3}) was studied with in situ X-ray photoelectron spectroscopy (XPS) on successive depositions of thermally evaporated methylammonium iodide (CH{sub 3}NH{sub 3}I) on a lead iodide (PbI{sub 2}) film. This deposition method mimics the “two-step” synthesis method commonly used in device fabrication. We find that several competing processes occur during the formation of perovskite CH{sub 3}NH{sub 3}PbI{sub 3}. Our most important finding is that during vapour deposition of CH{sub 3}NH{sub 3}I onto PbI{sub 2}, at least two carbon species are present in the resulting material, while only one nitrogen species is present. This suggests that CH{sub 3}NH{sub 3}I can dissociate during the transition to a perovskite phase, and some of the resulting molecules can be incorporated into the perovskite. The effect of partial CH{sub 3}NH{sub 3} substitution with CH{sub 3} was evaluated, and electronic structure calculations show that CH{sub 3} defects would impact the photovoltaic performance in perovskite solar cells. The possibility that not all A sites in the APbI{sub 3} perovskite are occupied by CH{sub 3}NH{sub 3} is therefore an important consideration when evaluating the performance of organometallic trihalide solar cells synthesized using typical approaches.

History of the bubble chamber and related active- and internal-target nuclear tracking detectors

International Nuclear Information System (INIS)

Becchetti, F.D.

2015-01-01

Donald Glaser, 1960 Nobel laureate in Physics, recently passed away (2013), as have many of his colleagues who were involved with the early development of bubble chambers at the University of Michigan. In this paper I will review those early years and the subsequent wide-spread application of active-target (AT) bubble chambers that dominated high-energy physics (HEP) research for over thirty years. Some of the related, but more modern nuclear tracking detectors being used in HEP, neutrino astrophysics and dark-matter searches also will be discussed

New ways of polymeric ion track characterization

International Nuclear Information System (INIS)

Fink, D.; Mueller, M.; Ghosh, S.; Dwivedi, K.K.; Vacik, J.; Hnatowicz, V.; Cervena, J.; Kobayashi, Y.; Hirata, K.

1999-01-01

New ways have been applied for characterization of ion tracks in polymers in the last few years, which are essentially related to depth profile determinations of ions, molecules, or positrons penetrating into these tracks. In combination with tomography, the first three-dimensional results have been obtained. Extensive diffusion simulations accompanying the measurements have enabled us to obtain a better understanding of the transport processes going on in ion tracks. This paper gives an overview about the range of new possibilities accessible by these techniques, and summarizes the presently obtained understanding of ion tracks in polymers

Inferring animal densities from tracking data using Markov chains.

Science.gov (United States)

Whitehead, Hal; Jonsen, Ian D

2013-01-01

The distributions and relative densities of species are keys to ecology. Large amounts of tracking data are being collected on a wide variety of animal species using several methods, especially electronic tags that record location. These tracking data are effectively used for many purposes, but generally provide biased measures of distribution, because the starts of the tracks are not randomly distributed among the locations used by the animals. We introduce a simple Markov-chain method that produces unbiased measures of relative density from tracking data. The density estimates can be over a geographical grid, and/or relative to environmental measures. The method assumes that the tracked animals are a random subset of the population in respect to how they move through the habitat cells, and that the movements of the animals among the habitat cells form a time-homogenous Markov chain. We illustrate the method using simulated data as well as real data on the movements of sperm whales. The simulations illustrate the bias introduced when the initial tracking locations are not randomly distributed, as well as the lack of bias when the Markov method is used. We believe that this method will be important in giving unbiased estimates of density from the growing corpus of animal tracking data.

Inferring animal densities from tracking data using Markov chains.

Directory of Open Access Journals (Sweden)

Hal Whitehead

Full Text Available The distributions and relative densities of species are keys to ecology. Large amounts of tracking data are being collected on a wide variety of animal species using several methods, especially electronic tags that record location. These tracking data are effectively used for many purposes, but generally provide biased measures of distribution, because the starts of the tracks are not randomly distributed among the locations used by the animals. We introduce a simple Markov-chain method that produces unbiased measures of relative density from tracking data. The density estimates can be over a geographical grid, and/or relative to environmental measures. The method assumes that the tracked animals are a random subset of the population in respect to how they move through the habitat cells, and that the movements of the animals among the habitat cells form a time-homogenous Markov chain. We illustrate the method using simulated data as well as real data on the movements of sperm whales. The simulations illustrate the bias introduced when the initial tracking locations are not randomly distributed, as well as the lack of bias when the Markov method is used. We believe that this method will be important in giving unbiased estimates of density from the growing corpus of animal tracking data.

Effect of cross-correlation on track-to-track fusion

Science.gov (United States)

Saha, Rajat K.

1994-07-01

Since the advent of target tracking systems employing a diverse mixture of sensors, there has been increasing recognition by air defense system planners and other military system analysts of the need to integrate these tracks so that a clear air picture can be obtained in a command center. A popular methodology to achieve this goal is to perform track-to-track fusion, which performs track-to-track association as well as kinematic state vector fusion. This paper seeks to answer analytically the extent of improvement achievable by means of kinetic state vector fusion when the tracks are obtained from dissimilar sensors (e.g., Radar/ESM/IRST/IFF). It is well known that evaluation of the performance of state vector fusion algorithms at steady state must take into account the effects of cross-correlation between eligible tracks introduced by the input noise which, unfortunately, is often neglected because of added computational complexity. In this paper, an expression for the steady-state cross-covariance matrix for a 2D state vector track-to-track fusion is obtained. This matrix is shown to be a function of the parameters of the Kalman filters associated with the candidate tracks being fused. Conditions for positive definiteness of the cross-covariance matrix have been derived and the effect of positive definiteness on performance of track-to-track fusion is also discussed.

Person and gesture tracking with smart stereo cameras

Science.gov (United States)

Gordon, Gaile; Chen, Xiangrong; Buck, Ron

2008-02-01

Physical security increasingly involves sophisticated, real-time visual tracking of a person's location inside a given environment, often in conjunction with biometrics and other security-related technologies. However, demanding real-world conditions like crowded rooms, changes in lighting and physical obstructions have proved incredibly challenging for 2D computer vision technology. In contrast, 3D imaging technology is not affected by constant changes in lighting and apparent color, and thus allows tracking accuracy to be maintained in dynamically lit environments. In addition, person tracking with a 3D stereo camera can provide the location and movement of each individual very precisely, even in a very crowded environment. 3D vision only requires that the subject be partially visible to a single stereo camera to be correctly tracked; multiple cameras are used to extend the system's operational footprint, and to contend with heavy occlusion. A successful person tracking system, must not only perform visual analysis robustly, but also be small, cheap and consume relatively little power. The TYZX Embedded 3D Vision systems are perfectly suited to provide the low power, small footprint, and low cost points required by these types of volume applications. Several security-focused organizations, including the U.S Government, have deployed TYZX 3D stereo vision systems in security applications. 3D image data is also advantageous in the related application area of gesture tracking. Visual (uninstrumented) tracking of natural hand gestures and movement provides new opportunities for interactive control including: video gaming, location based entertainment, and interactive displays. 2D images have been used to extract the location of hands within a plane, but 3D hand location enables a much broader range of interactive applications. In this paper, we provide some background on the TYZX smart stereo cameras platform, describe the person tracking and gesture tracking systems

NucliTrack: an integrated nuclei tracking application.

Science.gov (United States)

Cooper, Sam; Barr, Alexis R; Glen, Robert; Bakal, Chris

2017-10-15

Live imaging studies give unparalleled insight into dynamic single cell behaviours and fate decisions. However, the challenge of reliably tracking single cells over long periods of time limits both the throughput and ease with which such studies can be performed. Here, we present NucliTrack, a cross platform solution for automatically segmenting, tracking and extracting features from fluorescently labelled nuclei. NucliTrack performs similarly to other state-of-the-art cell tracking algorithms, but NucliTrack's interactive, graphical interface makes it significantly more user friendly. NucliTrack is available as a free, cross platform application and open source Python package. Installation details and documentation are at: http://nuclitrack.readthedocs.io/en/latest/ A video guide can be viewed online: https://www.youtube.com/watch?v=J6e0D9F-qSU Source code is available through Github: https://github.com/samocooper/nuclitrack. A Matlab toolbox is also available at: https://uk.mathworks.com/matlabcentral/fileexchange/61479-samocooper-nuclitrack-matlab. sam@socooper.com. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

Trigger tracking for the LHCb upgrade

CERN Multimedia

Dungs, K

2014-01-01

This poster presents a trigger system for the upgraded LHCb detector, scheduled to begin operation in 2020. The proposed trigger system is implemented entirely in software. We show that track reconstruction of a similar quality to that available in the offline algorithms can be performed on the full inelastic pp-collision rate. A track finding efficiency of 98.8% relative to offline can be achieved for good trigger tracks. The CPU time required for this reconstruction is less than 60% of the available budget.

Further promotion of the use of mosses and lichens for studies of atmospheric deposition of trace elements

International Nuclear Information System (INIS)

Steinnes, Eiliv

2001-01-01

Some recent and ongoing studies related to the use of mosses as biomonitors of atmospheric metal deposition are briefly reviewed. Issues discussed in particular are the conversion of concentration in moss to absolute deposition values, introduction of a second-generation ICP-MS instrument for moss analysis, determination of stable lead isotope ratios in mosses for source apportionment, and temporal trends of lead and cadmium deposition in Norway. A novel nuclear technique for the determination of fluorine in mosses surrounding an aluminium smelter is presented. (author)

Maximum-likelihood-based extended-source spatial acquisition and tracking for planetary optical communications

Science.gov (United States)

Tsou, Haiping; Yan, Tsun-Yee

1999-04-01

This paper describes an extended-source spatial acquisition and tracking scheme for planetary optical communications. This scheme uses the Sun-lit Earth image as the beacon signal, which can be computed according to the current Sun-Earth-Probe angle from a pre-stored Earth image or a received snapshot taken by other Earth-orbiting satellite. Onboard the spacecraft, the reference image is correlated in the transform domain with the received image obtained from a detector array, which is assumed to have each of its pixels corrupted by an independent additive white Gaussian noise. The coordinate of the ground station is acquired and tracked, respectively, by an open-loop acquisition algorithm and a closed-loop tracking algorithm derived from the maximum likelihood criterion. As shown in the paper, the optimal spatial acquisition requires solving two nonlinear equations, or iteratively solving their linearized variants, to estimate the coordinate when translation in the relative positions of onboard and ground transceivers is considered. Similar assumption of linearization leads to the closed-loop spatial tracking algorithm in which the loop feedback signals can be derived from the weighted transform-domain correlation. Numerical results using a sample Sun-lit Earth image demonstrate that sub-pixel resolutions can be achieved by this scheme in a high disturbance environment.

A polymorphism in AGT and AGTR1 gene is associated with lead-related high blood pressure.

Science.gov (United States)

Kim, Hyung-Ki; Lee, Hwayoung; Kwon, Jun-Tack; Kim, Hak-Jae

2015-12-01

We investigated the association of polymorphisms in two renin-angiotensin system-related genes, expressed as angiotensinogen (AGT) and angiotensin II type 1 receptor (AGTR1), with blood lead levels and lead-related blood pressure in lead-exposed male workers in Korea. A cross-sectional study involving 808 lead-exposed male workers in Korea was conducted using a restriction fragment length polymorphism-based strategy to differentiate the various genotypes of polymorphisms in the AGT and AGTR1 genes. The association of clinical characteristics with genotypes as modifiers was estimated after adjustment for age, smoking status, drinking status, body mass index and job duration of each subject. Genotype and allele frequencies of the M235T polymorphism in AGT were associated with lead-related high blood pressure status. Moreover, blood lead levels were associated with allele frequencies of the AGT M235T polymorphism. These results suggested that the M/M genotype and M allele of AGT are risk factors for lead-related high blood pressure. © The Author(s) 2014.

Quality of Slab Track Construction – Track Alignment Design and Track Geometry

Directory of Open Access Journals (Sweden)

Šestáková Janka

2015-05-01

Full Text Available The slab track superstructure design (without ballast is a perspective construction especially for building tunnels and bridges in the modernized sections of railway tracks in Slovakia. Monitoring of the structure described in this article is focused on the transition areas between standard structure with ballast and slab track construction.

Management of Work–Related Injuries Leading to Amputation and Its Relation with Treatment Outcome

Directory of Open Access Journals (Sweden)

Iravan Masoudi-Asl

2011-04-01

Full Text Available Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal" mso-tstyle-rowband-size:0 mso-tstyle-colband-size:0 mso-style-noshow:yes mso-style-priority:99 mso-style-parent:"" mso-padding-alt:0mm 5.4pt 0mm 5.4pt mso-para-margin-top:0mm mso-para-margin-right:0mm mso-para-margin-bottom:10.0pt mso-para-margin-left:0mm line-height:115% mso-pagination:widow-orphan font-size:11.0pt font-family:"Calibri","sans-serif" mso-ascii-font-family:Calibri mso-ascii-theme-font:minor-latin mso-hansi-font-family:Calibri mso-hansi-theme-font:minor-latin mso-bidi-font-family:Arial mso-bidi-theme-font:minor-bidi}   Objective: Work related accidents are considered as a significant health problem of working population. The goal of this study was to determine relation of treatment management with treatment outcome of Work-Related injuries leading to amputation.   Materials & Methods: current study was based on correlation method which was evidence based and was based on actual data of medical records of occupational accidents leading to amputations. Study population included all injuries that suffered limb amputation due to work and were referred to Laleh hospital during 2005 to 2009 (N=135. The data were collected by check list and analyzed by descriptive and inferential Statistics.   Results: Taking care method had a considerable effect on success of replant operation of that limb (P<0.001 so that in 95.23% of injuries whom principles of primary care had been done for them during transportation of amputated limb to hospital, had a successful operation. Treatment results of injuries in large limbs have had a strong relation to interval of incident occurrence to start of operation (P=0.038 How to refer injuries to hospital has not had a meaningful impact on treatment outcome (P=0.469 although referring injuries from health centers of workplace directly to hospital had more successful result comparing to

Mobilized plasma lead as an index of lead body burden and its relation to the heme-related indices.

Science.gov (United States)

Sakai, T; Ushio, K; Ikeya, Y

1998-07-01

Plasma lead (Pb-P) from workers were distributed in two main fractions: a protein bound fraction and low molecular weight fractions. Lead mobilized into plasma by CaEDTA was mainly observed in the low molecular weight fraction corresponding to lead disodium ethylenediamine tetraacetic acid (PbEDTA). The peak levels of Pb-P was attained around 1.5 and 2.5 hours after the start of CaEDTA injection. Pb-P and blood lead levels (Pb-B) at 2 h after the injection were 4.26 (+/- 2.84) and 0.96 (+/- 0.27) fold of the initial levels just before the injection. Pb-P concentrations at 2 hours after the start of CaEDTA injection (MPb-P) were well correlated (r = 0.740) with amounts of lead excreted in urine for 24 h thereafter (MPb-U). log MPb-P as well as log MPb-U were correlated with Pb-B (r = 0.765 and 0.817, respectively). Correlation coefficients of lead body burden (MPb-P or MPb-U) vs the logarithms of the effect indices (delta-aminolevulinic acid (ALA) dehydratase, ALA in urine, coproporphyrin in urine, and erythrocyte zinc protoporphyrin) were higher than the correlation coefficients of exposure indices (Pb-B or Pb-U) vs the logarithms of the effect indices. Thus the biological effect monitoring is significant and reliable for evaluating the functional components of lead body burden (MPb-P or MPb-U).

Fluorescent nanodiamond tracking reveals intraneuronal transport abnormalities induced by brain-disease-related genetic risk factors

Science.gov (United States)

Haziza, Simon; Mohan, Nitin; Loe-Mie, Yann; Lepagnol-Bestel, Aude-Marie; Massou, Sophie; Adam, Marie-Pierre; Le, Xuan Loc; Viard, Julia; Plancon, Christine; Daudin, Rachel; Koebel, Pascale; Dorard, Emilie; Rose, Christiane; Hsieh, Feng-Jen; Wu, Chih-Che; Potier, Brigitte; Herault, Yann; Sala, Carlo; Corvin, Aiden; Allinquant, Bernadette; Chang, Huan-Cheng; Treussart, François; Simonneau, Michel

2017-05-01

Brain diseases such as autism and Alzheimer's disease (each inflicting >1% of the world population) involve a large network of genes displaying subtle changes in their expression. Abnormalities in intraneuronal transport have been linked to genetic risk factors found in patients, suggesting the relevance of measuring this key biological process. However, current techniques are not sensitive enough to detect minor abnormalities. Here we report a sensitive method to measure the changes in intraneuronal transport induced by brain-disease-related genetic risk factors using fluorescent nanodiamonds (FNDs). We show that the high brightness, photostability and absence of cytotoxicity allow FNDs to be tracked inside the branches of dissociated neurons with a spatial resolution of 12 nm and a temporal resolution of 50 ms. As proof of principle, we applied the FND tracking assay on two transgenic mouse lines that mimic the slight changes in protein concentration (∼30%) found in the brains of patients. In both cases, we show that the FND assay is sufficiently sensitive to detect these changes.

An ensemble classifier to predict track geometry degradation

International Nuclear Information System (INIS)

Cárdenas-Gallo, Iván; Sarmiento, Carlos A.; Morales, Gilberto A.; Bolivar, Manuel A.; Akhavan-Tabatabaei, Raha

2017-01-01

Railway operations are inherently complex and source of several problems. In particular, track geometry defects are one of the leading causes of train accidents in the United States. This paper presents a solution approach which entails the construction of an ensemble classifier to forecast the degradation of track geometry. Our classifier is constructed by solving the problem from three different perspectives: deterioration, regression and classification. We considered a different model from each perspective and our results show that using an ensemble method improves the predictive performance. - Highlights: • We present an ensemble classifier to forecast the degradation of track geometry. • Our classifier considers three perspectives: deterioration, regression and classification. • We construct and test three models and our results show that using an ensemble method improves the predictive performance.

Robust Model Predictive Control Schemes for Tracking Setpoints

Directory of Open Access Journals (Sweden)

Vu Trieu Minh

2010-01-01

Full Text Available This paper briefly reviews the development of nontracking robust model predictive control (RMPC schemes for uncertain systems using linear matrix inequalities (LMIs subject to input saturated and softened state constraints. Then we develop two new tracking setpoint RMPC schemes with common Lyapunov function and with zero terminal equality subject to input saturated and softened state constraints. The novel tracking setpoint RMPC schemes are able to stabilize uncertain systems once the output setpoints lead to the violation of the state constraints. The state violation can be regulated by changing the value of the weighting factor. A brief comparative simulation study of the two tracking setpoint RMPC schemes is done via simple examples to demonstrate the ability of the softened state constraint schemes. Finally, some features of future research from this study are discussed.

Energy indicators for tracking sustainability in developing countries

International Nuclear Information System (INIS)

Kemmler, Andreas; Spreng, Daniel

2007-01-01

Due to the fact that human activities and most sustainability issues are closely related to energy use, the energy system is a sound framework for providing lead indicators for sustainable development. Common energy-economic models enable the estimation of future states of the energy system. An energy system-based lead indicator set can be used to develop consistent and coherent future indicator estimates and to track sustainability, a clear advantage over existing sets. In developed countries, the sustainability discussion is focused on environmental topics, while in developing countries the issues of poverty and equity are equally important. Consequently, for measuring sustainable development in a developing country, the inclusion of a poverty indicator in a set of lead indicators is essential. By correlation and descriptive analysis, it is shown that reliable energy-based indicators of poverty can be created. Although no one-dimensional indicator is a comprehensive measure of poverty, the explanatory power of energy poverty indicators is comparable to that of other poverty indicators. Thus, the use of energy indicators is not restricted to environmental and economic issues but is also relevant for social issues

Online Simulation of Radiation Track Structure Project

Science.gov (United States)

Plante, Ianik

2015-01-01

Space radiation comprises protons, helium and high charged and energy (HZE) particles. High-energy particles are a concern for human space flight, because they are no known options for shielding astronauts from them. When these ions interact with matter, they damage molecules and create radiolytic species. The pattern of energy deposition and positions of the radiolytic species, called radiation track structure, is highly dependent on the charge and energy of the ion. The radiolytic species damage biological molecules, which may lead to several long-term health effects such as cancer. Because of the importance of heavy ions, the radiation community is very interested in the interaction of HZE particles with DNA, notably with regards to the track structure. A desktop program named RITRACKS was developed to simulate radiation track structure. The goal of this project is to create a web interface to allow registered internal users to use RITRACKS remotely.

MRI-guided tumor tracking in lung cancer radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Cervino, Laura I; Jiang, Steve B [Center for Advanced Radiotherapy Technology and Department of Radiation Oncology, University of California San Diego, 3960 Health Sciences Dr., La Jolla, CA 92093-0865 (United States); Du, Jiang, E-mail: lcervino@ucsd.edu [Department of Radiology, University of California San Diego, 200 West Arbor Dr., San Diego, CA 92103-8226 (United States)

2011-07-07

Precise tracking of lung tumor motion during treatment delivery still represents a challenge in radiation therapy. Prototypes of MRI-linac hybrid systems are being created which have the potential of ionization-free real-time imaging of the tumor. This study evaluates the performance of lung tumor tracking algorithms in cine-MRI sagittal images from five healthy volunteers. Visible vascular structures were used as targets. Volunteers performed several series of regular and irregular breathing. Two tracking algorithms were implemented and evaluated: a template matching (TM) algorithm in combination with surrogate tracking using the diaphragm (surrogate was used when the maximum correlation between the template and the image in the search window was less than specified), and an artificial neural network (ANN) model based on the principal components of a region of interest that encompasses the target motion. The mean tracking error e and the error at 95% confidence level e{sub 95} were evaluated for each model. The ANN model led to e = 1.5 mm and e{sub 95} = 4.2 mm, while TM led to e = 0.6 mm and e{sub 95} = 1.0 mm. An extra series was considered separately to evaluate the benefit of using surrogate tracking in combination with TM when target out-of-plane motion occurs. For this series, the mean error was 7.2 mm using only TM and 1.7 mm when the surrogate was used in combination with TM. Results show that, as opposed to tracking with other imaging modalities, ANN does not perform well in MR-guided tracking. TM, however, leads to highly accurate tracking. Out-of-plane motion could be addressed by surrogate tracking using the diaphragm, which can be easily identified in the images.

Visual Vehicle Tracking Based on Deep Representation and Semisupervised Learning

Directory of Open Access Journals (Sweden)

Yingfeng Cai

2017-01-01

Full Text Available Discriminative tracking methods use binary classification to discriminate between the foreground and background and have achieved some useful results. However, the use of labeled training samples is insufficient for them to achieve accurate tracking. Hence, discriminative classifiers must use their own classification results to update themselves, which may lead to feedback-induced tracking drift. To overcome these problems, we propose a semisupervised tracking algorithm that uses deep representation and transfer learning. Firstly, a 2D multilayer deep belief network is trained with a large amount of unlabeled samples. The nonlinear mapping point at the top of this network is subtracted as the feature dictionary. Then, this feature dictionary is utilized to transfer train and update a deep tracker. The positive samples for training are the tracked vehicles, and the negative samples are the background images. Finally, a particle filter is used to estimate vehicle position. We demonstrate experimentally that our proposed vehicle tracking algorithm can effectively restrain drift while also maintaining the adaption of vehicle appearance. Compared with similar algorithms, our method achieves a better tracking success rate and fewer average central-pixel errors.

Performance measurement of the upgraded D0 central track trigger

International Nuclear Information System (INIS)

Mommsen, Remigius K.; Manchester U.

2006-01-01

The D0 experiment was upgraded in spring 2006 to harvest the full physics potential of the Tevatron accelerator at Fermi National Accelerator Laboratory, Batavia, Illinois, USA. It is expected that the peak luminosity delivered by the accelerator will increase to over 300 x 10 30 cm -2 s -1 . One of the upgraded systems is the Central Track Trigger (CTT). The CTT uses the Central Fiber Tracker (CFT) and Preshower detectors to identify central tracks with p T > 1.5GeV at the first trigger level. Track candidates are formed by comparing fiber hits to predefined track equations. In order to minimize latency, this operation is performed in parallel using combinatorial logic implemented in FPGAs. Limited hardware resources prevented the use of the full granularity of the CFT. This leads to a high fake track rate as the occupancy increases. In order to mitigate the problem, new track-finding hardware was designed and commissioned. We report on the upgrade and the improved performance of the CTT system

TAGGING, TRACKING AND LOCATING WITHOUT GPS

Energy Technology Data Exchange (ETDEWEB)

Cordaro, J.; Coleman, T.; Shull, D.

2012-07-08

The Savannah River National Laboratory (SRNL) was requested to lead a Law Enforcement Working Group that was formed to collaborate on common operational needs. All agencies represented on the working group ranked their need to tag, track, and locate a witting or unwitting target as their highest priority. Specifically, they were looking for technologies more robust than Global Positioning Satellite (GPS), could communicate back to the owner, and worked where normal cell phone communications did not work or were unreliable. SRNL brought together multiple technologies in a demonstration that was held in in various Alaska venues, including metropolitan, wilderness, and at-sea that met the working group's requirements. Using prototypical technologies from Boeing, On Ramp, and Fortress, SRNL was able to demonstrate the ability to track personnel and material in all scenarios including indoors, in heavily wooden areas, canyons, and in parking garages. In all cases GPS signals were too weak to measure. Bi-directional communication was achieved in areas that Wi-Fi, cell towers, or traditional radios would not perform. The results of the exercise will be presented. These technologies are considered ideal for tracking high value material such has nuclear material with a platform that allows seamless tracking anywhere in the world, indoors or outdoors.

Automatic tracking of cells for video microscopy in patch clamp experiments.

Science.gov (United States)

Peixoto, Helton M; Munguba, Hermany; Cruz, Rossana M S; Guerreiro, Ana M G; Leao, Richardson N

2014-06-20

Visualisation of neurons labeled with fluorescent proteins or compounds generally require exposure to intense light for a relatively long period of time, often leading to bleaching of the fluorescent probe and photodamage of the tissue. Here we created a technique to drastically shorten light exposure and improve the targeting of fluorescent labeled cells that is specially useful for patch-clamp recordings. We applied image tracking and mask overlay to reduce the time of fluorescence exposure and minimise mistakes when identifying neurons. Neurons are first identified according to visual criteria (e.g. fluorescence protein expression, shape, viability etc.) and a transmission microscopy image Differential Interference Contrast (DIC) or Dodt contrast containing the cell used as a reference for the tracking algorithm. A fluorescence image can also be acquired later to be used as a mask (that can be overlaid on the target during live transmission video). As patch-clamp experiments require translating the microscope stage, we used pattern matching to track reference neurons in order to move the fluorescence mask to match the new position of the objective in relation to the sample. For the image processing we used the Open Source Computer Vision (OpenCV) library, including the Speeded-Up Robust Features (SURF) for tracking cells. The dataset of images (n = 720) was analyzed under normal conditions of acquisition and with influence of noise (defocusing and brightness). We validated the method in dissociated neuronal cultures and fresh brain slices expressing Enhanced Yellow Fluorescent Protein (eYFP) or Tandem Dimer Tomato (tdTomato) proteins, which considerably decreased the exposure to fluorescence excitation, thereby minimising photodamage. We also show that the neuron tracking can be used in differential interference contrast or Dodt contrast microscopy. The techniques of digital image processing used in this work are an important addition to the set of microscopy

Quantifying the effect of seasonal and vertical habitat tracking on planktonic foraminifera proxies

Directory of Open Access Journals (Sweden)

L. Jonkers

2017-06-01

Full Text Available The composition of planktonic foraminiferal (PF calcite is routinely used to reconstruct climate variability. However, PF ecology leaves a large imprint on the proxy signal: seasonal and vertical habitats of PF species vary spatially, causing variable offsets from annual mean surface conditions recorded by sedimentary assemblages. PF seasonality changes with temperature in a way that minimises the environmental change that individual species experience and it is not unlikely that changes in depth habitat also result from such habitat tracking. While this behaviour could lead to an underestimation of spatial or temporal trends as well as of variability in proxy records, most palaeoceanographic studies are (implicitly based on the assumption of a constant habitat. Up to now, the effect of habitat tracking on foraminifera proxy records has not yet been formally quantified on a global scale. Here we attempt to characterise this effect on the amplitude of environmental change recorded in sedimentary PF using core top δ18O data from six species. We find that the offset from mean annual near-surface δ18O values varies with temperature, with PF δ18O indicating warmer than mean conditions in colder waters (on average by −0.1 ‰ (equivalent to 0.4 °C per °C, thus providing a first-order quantification of the degree of underestimation due to habitat tracking. We use an empirical model to estimate the contribution of seasonality to the observed difference between PF and annual mean δ18O and use the residual Δδ18O to assess trends in calcification depth. Our analysis indicates that given an observation-based model parametrisation calcification depth increases with temperature in all species and sensitivity analysis suggests that a temperature-related seasonal habitat adjustment is essential to explain the observed isotope signal. Habitat tracking can thus lead to a significant reduction in the amplitude of recorded environmental change

LHCb Run II tracking performance and prospects for the Upgrade

CERN Multimedia

2016-01-01

The LHCb tracking system consists of a Vertex Locator around the interaction point, a tracking station with four layers of silicon strip detectors in front of the magnet, and three tracking stations, using either straw-tubes or silicon strip detectors, behind the magnet. This system allows to reconstruct charged particles with a high efficiency (typically > 95% for particles with momentum > 5 GeV) and an excellent momentum resolution (0.5% for particles with momentum < 20 GeV). The high momentum resolution results in very narrow mass peaks, leading to a very good signal-to-background ratio in such key channels as $B_s\\to\\mu^+\\mu^-$. Furthermore an optimal decay time resolution is an essential element in the studies of time dependent CP violation. For Run II a novel reconstruction strategy was adopted, allowing to run the same track reconstruction in the software trigger as offline. This convergence was possible due to a staged approach in the track reconstruction and a large reduction in the processing tim...

Enhancement of tracking performance in electro-optical system based on servo control algorithm

Science.gov (United States)

Choi, WooJin; Kim, SungSu; Jung, DaeYoon; Seo, HyoungKyu

2017-10-01

Modern electro-optical surveillance and reconnaissance systems require tracking capability to get exact images of target or to accurately direct the line of sight to target which is moving or still. This leads to the tracking system composed of image based tracking algorithm and servo control algorithm. In this study, we focus on the servo control function to minimize the overshoot in the tracking motion and do not miss the target. The scheme is to limit acceleration and velocity parameters in the tracking controller, depending on the target state information in the image. We implement the proposed techniques by creating a system model of DIRCM and simulate the same environment, validate the performance on the actual equipment.

Calibration of Nuclear Track Detectors

International Nuclear Information System (INIS)

Vukovic, J.B; Antanasijevic, R.; Novakovic, V.; Tasic, M.

1998-01-01

In this work we compare some of our preliminary results relating to the calibration Nuclear Track Detectors (NTD) with corresponding results obtained from other participants at the First International Intercomparison of Image Analyzers (III 97/98). Thirteen laboratories from Algeria, China, Czech Rep., France. Germany, Greece, Hungary, India, Italy, Mexico, Saudi Arabia, Slovenia and Yugoslavia participated in the III A 97/98. The NTD was 'Tustrack', Bristol. This type of CR-39 detector was etched by the organizer (J.Paltarey of al, Atomic Energy Research Institute, HPD, Budapest, Hungary). Etching condition was: 6N NaOH, 70 0C . Seven series detectors were exposed with the sources: B(n,a)Li, Am-241, Pu-Be(n,p), Radon and Am-Cm-Pu. Following parameters of exposed detectors were measured: track density of different sorts of tracks (circular, elliptical, track overlapping, their diameters, major and minor axis and other). (authors)

Maximum power point tracking

International Nuclear Information System (INIS)

Enslin, J.H.R.

1990-01-01

A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

The ship-borne infrared searching and tracking system based on the inertial platform

Science.gov (United States)

Li, Yan; Zhang, Haibo

2011-08-01

As a result of the radar system got interferenced or in the state of half silent ,it can cause the guided precision drop badly In the modern electronic warfare, therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings, but when interference is in the process of radar leading ,especially the electro-optical equipment is influenced by the roll, pitch and yaw rotation ,it can affect the target appear outside of the field of optoelectronic devices for a long time, so the infrared optoelectronic equipment can not exert the superiority, and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly , the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene, the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing

Community- and family-level factors influence care-giver choice to screen blood lead levels of children in a mining community.

Science.gov (United States)

Moodie, S M; Tsui, E K; Silbergeld, E K

2010-07-01

Bunker Hill, in Kellogg, Idaho, formerly a lead mine (1884-1981) and smelter (1917-1981), is now a Superfund site listed on the Environmental Protection Agency's (EPA) National Priorities List. Lead contamination from the site is widespread due to past smelter discharges to land, water, and air, placing children at risk for both exposure to lead and resultant health effects of lead. Since 1983, the EPA has used child blood lead levels to inform the clean-up standards for the Bunker Hill Superfund site. This study was undertaken to examine factors that have contributed to the significant fall-off in the rates and numbers of children being screened for blood lead in Kellogg (number screened decreased from 195 to 8 from 2002 to 2007). The goal of this research project was to define community- and family-level factors which influence care-giver choice to screen blood lead levels of their children in this environment. This formative research study used mixed methods and was comprised of three research components: (1) preliminary interviews using community-based participatory research methods to define key research questions of relevance to community members, government and NGOs working in relation to the Bunker Hill clean-up; (2) a quantitative analysis of a cross-sectional household survey conducted with adult care-givers about child blood lead screening in Kellogg; and (3) ethnographic community rapid assessment methods formed the in-depth interview process and qualitative analysis. The survey showed the likelihood of blood lead screening that for children under the age of 18 years increases 34% with each one-year increase in current age of the child (95% CI, 1.08-1.67, p-value=0.009), and decreases 45% with annual household income greater than $10,000 (95% CI, 0.35-0.88, p-value=0.013). Sibling birth order increased the likelihood of blood lead screening by 61% (95% CI, 1.04-2.48, p-value=0.032) for each successive child. Female children were rated by their care

Studies of cadmium, mercury and lead in man. The value of X-ray fluorescence measurements in vivo

Energy Technology Data Exchange (ETDEWEB)

Boerjesson, J

1996-10-01

Two XRF methods have been used for in vivo studies of mercury, cadmium and lead. Persons with a history of long-term occupational mercury exposure had elevated mercury concentrations in their kidneys (up to 65 {mu}g/g). The minimum detectable concentration varied between 12 and 45 {mu}g/g. Battery plant workers had elevated cadmium concentrations in their kidneys (up to 350 {mu}g/g) and liver (up to 80 {mu}g/g), with mean values about 3-5 times higher than the general population. The mean ratio between concentrations of cadmium in kidney and liver was 7. Levels in kidney and liver indicated that a simple integration of cadmium in work-place air is not sufficient to describe the body burden. Fingerbone lead in smelters was 6-8 times higher than in members of the general population. The half-time of bone lead in active workers was estimated to about 5 years during the accumulation phase. A model for description of a person`s lead exposure in terms of lead in fingerbone, lead in blood and time of exposure has been developed and can be used, e.g. for retrospective blood lead estimates if the period of exposure and the current fingerbone lead is known. This will be of value for the evaluation of toxic effects of long-term lead exposure when data on previous lead levels are lacking. In total, in vivo measurements of mercury, cadmium and lead give unique information, which has shown to be an important tool for understanding of metal kinetics and toxicity. If the precision and accuracy of the method can be further improved, the technique will also have a given place in the clinical practice. 168 refs, 9 figs, 3 tabs

Nanoscale measurements of proton tracks using fluorescent nuclear track detectors

Energy Technology Data Exchange (ETDEWEB)

Sawakuchi, Gabriel O., E-mail: gsawakuchi@mdanderson.org; Sahoo, Narayan [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and Graduate School of Biomedical Sciences, The University of Texas, Houston, Texas 77030 (United States); Ferreira, Felisberto A. [Department of Nuclear Physics, University of Sao Paulo, SP 05508-090 (Brazil); McFadden, Conor H. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Hallacy, Timothy M. [Biophysics Program, Harvard University, Cambridge, Massachusetts 02138 (United States); Granville, Dal A. [Department of Medical Physics, The Ottawa Hospital Cancer Centre, Ottawa, Ontario K1H 8L6 (Canada); Akselrod, Mark S. [Crystal Growth Division, Landauer, Inc., Stillwater, Oklahoma 74074 (United States)

2016-05-15

Purpose: The authors describe a method in which fluorescence nuclear track detectors (FNTDs), novel track detectors with nanoscale spatial resolution, are used to determine the linear energy transfer (LET) of individual proton tracks from proton therapy beams by allowing visualization and 3D reconstruction of such tracks. Methods: FNTDs were exposed to proton therapy beams with nominal energies ranging from 100 to 250 MeV. Proton track images were then recorded by confocal microscopy of the FNTDs. Proton tracks in the FNTD images were fit by using a Gaussian function to extract fluorescence amplitudes. Histograms of fluorescence amplitudes were then compared with LET spectra. Results: The authors successfully used FNTDs to register individual proton tracks from high-energy proton therapy beams, allowing reconstruction of 3D images of proton tracks along with delta rays. The track amplitudes from FNTDs could be used to parameterize LET spectra, allowing the LET of individual proton tracks from therapeutic proton beams to be determined. Conclusions: FNTDs can be used to directly visualize proton tracks and their delta rays at the nanoscale level. Because the track intensities in the FNTDs correlate with LET, they could be used further to measure LET of individual proton tracks. This method may be useful for measuring nanoscale radiation quantities and for measuring the LET of individual proton tracks in radiation biology experiments.

The effect of the lead from the ambient air and health evaluation of the school children population

International Nuclear Information System (INIS)

Kochubovski, Mihail Vasil

2003-01-01

Veles with its geographic position, atmospheric specifics, urban and industrial concentration with wrong location of the Lead and Zink Smelter-opposite to the Wind Rose, multiplied by inconvenient power plants is analysedhydro-topographic factors has all predispositions for huge and continuous air pollution (3 decades) with specific agent-lead. There is statistically high significant difference by Student t-test (t = 15.14; p 3 ), related to the control area-v.lvankovci (x = 0.03 μg/m 3 ) . Registered average annual concentration of lead in the ambient air is 89% higher than the recommended value from WHO and EU (0.5 μg/m 3 ). Increased concentration of lead in the ambient air, represent high risk factor for the health of the exposed children population in the city of Veles. There has been registered statistically significant difference (t = 3.96; p 20 μg/dl). Pearson test of correlation between registered values of EEG and the intelligence quotient, has shown negative moderate correlation (r = -0.31; p < 0.05). With Pearson test of correlation between registered values of EEG and blood-lead levels, has been got low correlation (r = 0.12; p < 0.05). It can be concluded that all registered outputs in the examined children can be reversible, and still they are in compensatory phase without clear clinical sign of disease. Electromyography has not shown any disorder in neuromuscular conductivity in selected children. Pearson test of correlation between registered values of SEMG and blood-lead levels, has shown negative correlation (r = -0.07; p < 0.05). Results shows that selected children are with normal activity of the autonomous nervous system and they adequately respond to the stress situation. It can be concluded that there is an obvious environmental-health risk in Veles, with enough evidences for the pollution of the environment in Veles, as well the impact of higher blood-lead levels to NAG, IQ, graphomotoric ability in the examined children, as well to EEG

Nuclear Fragmentation Induced by Relativistic Projectiles Studied in the 4$\\pi$ Configuration of Plastic Track Detectors

CERN Multimedia

2002-01-01

% EMU19 \\\\ \\\\ The collisions of heavy ions at relativistic energies have been studied to explore a number of questions related with hot and dense nuclear matter in order to extend our knowledge of nuclear equation-of-state. There are other aspects of these interactions which are studied to expound the process of projectile and/or target disintegrations. The disintegrations in question could be simply binary fissions or more complex processes leading to spallation or complete fragmentation. These important aspects of nuclear reactions are prone to investigations with nuclear track detectors. \\\\ \\\\One of the comparatively new track detector materials, CR-39, is sensitive enough to record particles of Z~$\\geq$~6 with almost 100\\% efficiency up to highly relativistic energies. The wide angle acceptance and exclusive measurements possible with plastic track detectors offer an opportunity to use them in a variety of situations in which high energy charged fragments are produced. The off-line nature of measuring tra...

Dose-Response Relationship between Cumulative Occupational Lead Exposure and the Associated Health Damages: A 20-Year Cohort Study of a Smelter in China

OpenAIRE

Yue Wu; Jun-Ming Gu; Yun Huang; Yan-Ying Duan; Rui-Xue Huang; Jian-An Hu

2016-01-01

Long-term airborne lead exposure, even below official occupational limits, has been found to cause lead poisoning at higher frequencies than expected, which suggests that China’s existing occupational exposure limits should be reexamined. A retrospective cohort study was conducted on 1832 smelting workers from 1988 to 2008 in China. These were individuals who entered the plant and came into continuous contact with lead at work for longer than 3 months. The dose-response relationship between o...

Tracking errors in a prototype real-time tumour tracking system

International Nuclear Information System (INIS)

Sharp, Gregory C; Jiang, Steve B; Shimizu, Shinichi; Shirato, Hiroki

2004-01-01

In motion-compensated radiation therapy, radio-opaque markers can be implanted in or near a tumour and tracked in real-time using fluoroscopic imaging. Tracking these implanted markers gives highly accurate position information, except when tracking fails due to poor or ambiguous imaging conditions. This study investigates methods for automatic detection of tracking errors, and assesses the frequency and impact of tracking errors on treatments using the prototype real-time tumour tracking system. We investigated four indicators for automatic detection of tracking errors, and found that the distance between corresponding rays was most effective. We also found that tracking errors cause a loss of gating efficiency of between 7.6 and 10.2%. The incidence of treatment beam delivery during tracking errors was estimated at between 0.8% and 1.25%

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

Science.gov (United States)

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

2012-12-01

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

Multi-rate h2 tracking control with mixed continuous-discrete performance criteria

International Nuclear Information System (INIS)

Kahane, A.C.; Palmor, Z.J.; Mirkin, L.

1998-01-01

Control goals defined both in continuous and discrete time arise naturally in many sampled-data tracking control problems. The design methods found in the literature deal with each kind of those control goals separately, over-emphasizing one kind at the expense of the other. We formulate and solve these tracking control problems as an H2 optimization problem with a mixed continuous/discrete performance criterion. It is argued that the proposed setup enables tradeoff between the various control goals in a natural manner and thus leads to better tracking characteristics

Alpha particle and proton relative thermoluminescence efficiencies in LiF:Mg, Cu, P:is track structure theory up to the task?

International Nuclear Information System (INIS)

Horowitz, Y. S.; Siboni, D.; Oster, L.; Livingstone, J.; Guatelli, S.; Rosenfeld, A.; Emfietzoglou, D.; Bilski, P.; Obryk, B.

2008-01-01

Low-energy alpha particle and proton heavy charged particle (HCP) relative thermoluminescence (TL) efficiencies are calculated for the major dosimetric glow peak in LiF:Mg, Cu, P (MCP-N) in the framework of track structure theory (TST). The calculations employ previously published TRIPOS-E Monte Carlo track segment values of the radial dose in condensed phase LiF calculated at the Instituto National de Investigaciones Nucleares (Mexico) and experimentally measured normalised 60 Co gamma-induced TL dose-response functions, f(D), carried out at the Inst. of Nuclear Physics (Poland). The motivation for the calculations is to test the validity of TST in a TL system in which f(D) is not supra-linear (f(D) >1) and is not significantly dependent on photon energy contrary to the behaviour of the dose-response of composite peak 5 in the glow curve of LiF:Mg, Ti (TLD-100). The calculated HCP relative efficiencies in LiF:MCP-N are 23-87 % lower than the experimentally measured values, indicating a weakness in the major premise of TST which exclusively relates HCP effects to the radiation action of the secondary electrons liberated by the HCP slowing down. However, an analysis of the uncertainties involved in the TST calculations and experiments (i.e. experimental measurement of f(D) at high levels of dose, sample light self-absorption and accuracy in the estimation of D R, especially towards the end of the HCP track) indicate that these may be too large to enable a definite conclusion. More accurate estimation of sample light self-absorption, improved measurements of f(D) and full-track Monte Carlo calculations of D R incorporating improvements of the low-energy electron transport are indicated in order to reduce uncertainties and enable a final conclusion. (authors)

Alpha particle and proton relative thermoluminescence efficiencies in LiF:Mg,Cu,P:is track structure theory up to the task?

Science.gov (United States)

Horowitz, Y S; Siboni, D; Oster, L; Livingstone, J; Guatelli, S; Rosenfeld, A; Emfietzoglou, D; Bilski, P; Obryk, B

2012-07-01

Low-energy alpha particle and proton heavy charged particle (HCP) relative thermoluminescence (TL) efficiencies are calculated for the major dosimetric glow peak in LiF:Mg,Cu,P (MCP-N) in the framework of track structure theory (TST). The calculations employ previously published TRIPOS-E Monte Carlo track segment values of the radial dose in condensed phase LiF calculated at the Instituto National de Investigaciones Nucleares (Mexico) and experimentally measured normalised (60)Co gamma-induced TL dose-response functions, f(D), carried out at the Institute of Nuclear Physics (Poland). The motivation for the calculations is to test the validity of TST in a TL system in which f(D) is not supralinear (f(D) >1) and is not significantly dependent on photon energy contrary to the behaviour of the dose-response of composite peak 5 in the glow curve of LiF:Mg,Ti (TLD-100). The calculated HCP relative efficiencies in LiF:MCP-N are 23-87% lower than the experimentally measured values, indicating a weakness in the major premise of TST which exclusively relates HCP effects to the radiation action of the secondary electrons liberated by the HCP slowing down. However, an analysis of the uncertainties involved in the TST calculations and experiments (i.e. experimental measurement of f(D) at high levels of dose, sample light self-absorption and accuracy in the estimation of D(r), especially towards the end of the HCP track) indicate that these may be too large to enable a definite conclusion. More accurate estimation of sample light self-absorption, improved measurements of f(D) and full-track Monte Carlo calculations of D(r) incorporating improvements of the low-energy electron transport are indicated in order to reduce uncertainties and enable a final conclusion.

Radiation damage to DNA: The importance of track structure

CERN Document Server

Hill, M A

1999-01-01

A wide variety of biological effects are induced by ionizing radiation, from cell death to mutations and carcinogenesis. The biological effectiveness is found to vary not only with the absorbed dose but also with the type of radiation and its energy, i.e., with the nature of radiation tracks. An overview is presented of some of the biological experiments using different qualities of radiation, which when compared with Monte Carlo track structure studies, have highlighted the importance of the localized spatial properties of stochastic energy deposition on the nanometer scale at or near DNA. The track structure leads to clustering of damage which may include DNA breaks, base damage etc., the complexity of the cluster and therefore its biological repairability varying with radiation type. The ability of individual tracks to produce clustered damage, and the subsequent biological response are important in the assessment of the risk associated with low-level human exposure. Recent experiments have also shown that...

Correlation Filter Learning Toward Peak Strength for Visual Tracking.

Science.gov (United States)

Sui, Yao; Wang, Guanghui; Zhang, Li

2018-04-01

This paper presents a novel visual tracking approach to correlation filter learning toward peak strength of correlation response. Previous methods leverage all features of the target and the immediate background to learn a correlation filter. Some features, however, may be distractive to tracking, like those from occlusion and local deformation, resulting in unstable tracking performance. This paper aims at solving this issue and proposes a novel algorithm to learn the correlation filter. The proposed approach, by imposing an elastic net constraint on the filter, can adaptively eliminate those distractive features in the correlation filtering. A new peak strength metric is proposed to measure the discriminative capability of the learned correlation filter. It is demonstrated that the proposed approach effectively strengthens the peak of the correlation response, leading to more discriminative performance than previous methods. Extensive experiments on a challenging visual tracking benchmark demonstrate that the proposed tracker outperforms most state-of-the-art methods.

Natural environment in the area of copper smelter plants. Trend of changes

Directory of Open Access Journals (Sweden)

Łucja Strzelec

2012-06-01

Full Text Available Findings of air quality are brought forward in the area of copper industry impact with particular attention paid to copper smelter plants located in Legnica and Głogów area covering the period from 1980 to 2010. The paper identifies occurring changes and trends in the course of years. Lowering of dust-gaseous emissions from the most crucial sources in the area of LegnicaGłogów Copper Mining Region improved air quality in this region in the significant way. The fact is also of some importance that emission of pollutants from big sources combusting fuels for energy generation was reduced either by rundown of production or liquidation of some plants. Based on the conducted state environmental monitoring it is concluded that at present emission of pollutants from industrial sources affects air quality to a lesser degree. There are still problems of air protection waiting to be solved which are connected with: – emission of gaseous-dust pollutants from domestic-municipal sector i. e. so called low emission from individual heating of dwellings. The sources are low emitters where often coal is combusted together with various types of waste. Therefore after starting the period of centrally heated dwellings air quality monitoring stations recorded evidently the increase of dust and gaseous pollutants including benzo (a pirene. – pollutants emission from road transport which is the cause of high concentration of nitrogen oxides, carbon monoxide and hydrocarbons particularly in the vicinity of roads and streets of big road traffic density. Materials and methods: The base of the study were findings obtained from District Inspectorate of Environmental Protection in Legnica in the framework of carried out since 1991 the state environmental monitoring in national, regional and local network. In the period from 1980 till 1990 the studies performed Research Centre of Environmental Control in Legnica.

The Establishment of a Formal Midwest Renewable Energy Tracking System (M-RETS) Organization

Energy Technology Data Exchange (ETDEWEB)

Maria Redmond; Chela Bordas O' Connor

2010-06-30

The objectives identified in requesting and utilizing this funding has been met. The goal was to establish a formal, multi-jurisdictional organization to: (1) ensure the policy objectives of the participating jurisdictions are addressed through increased tradability of the Renewable Energy Credits (RECs) from M-RETS and to eliminate the possibility that a single jurisdiction will be the sole arbiter of the operation of the system; (2) facilitate the establishment of REC standards including the attributes related to, the creation, trading, and interaction with other trading and tracking systems; and (3) have a centralized and established organization that will be responsible for the contracting and governance responsibilities of a multi-jurisdictional tracking system. The M-RETS Inc. Board ensures that the system remains policy neutral; that the attributes of generation are tracked in a way that allows the system users to easily identify and trade relevant RECs; that the system can add jurisdictions as needed or desired; and that the tracking system operate in such a way to allow for the greatest access possible for those participating in other tracking or trading systems by allowing those systems to negotiate with a single M-RETS entity for the import and export of RECs. M-RETS as an organizational body participates and often leads the discussions related to the standardization of RECs and increasing the tradability of M-RETS RECs. M-RETS is a founding member of the Environmental Trading Network of North America (ETNNA) and continues to take a leadership role in the development of processes to facilitate trading among tracking systems and to standardize REC definitions. The Board of Directors of M-RETS, Inc., the non-profit corporation, continues to hold telephone/internet Board meetings. Legal counsel continues working with the board and APX management on a new agreement with APX. The board expects to have an agreement and corresponding fee structure in place by

Electrophoretic growth of lead zirconate titanate nanorods

Energy Technology Data Exchange (ETDEWEB)

Limmer, S.J.; Seraji, S.; Forbess, M.J.; Wu Yun; Chou, T.P.; Nguyen, C.; Cao Guozhong [Washington Univ., Seattle, WA (United States). Dept. of Materials Science and Engineering

2001-08-16

Nanorods of lead zirconate titanate (PZT)-a ferro- and piezoelectric material-up to 10 {mu}m in length and 70 to 150 nm in diameter are produced by sol-gel electrophoresis of PZT in a track-etched polycarbonate membrane, which is used as a template. (orig.)

Coupling meteorology, metal concentrations, and Pb isotopes for source attribution in archived precipitation samples.

Science.gov (United States)

Graney, Joseph R; Landis, Matthew S

2013-03-15

A technique that couples lead (Pb) isotopes and multi-element concentrations with meteorological analysis was used to assess source contributions to precipitation samples at the Bondville, Illinois USA National Trends Network (NTN) site. Precipitation samples collected over a 16month period (July 1994-October 1995) at Bondville were parsed into six unique meteorological flow regimes using a minimum variance clustering technique on back trajectory endpoints. Pb isotope ratios and multi-element concentrations were measured using high resolution inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) on the archived precipitation samples. Bondville is located in central Illinois, ~250km downwind from smelters in southeast Missouri. The Mississippi Valley Type ore deposits in Missouri provided a unique multi-element and Pb isotope fingerprint for smelter emissions which could be contrasted to industrial emissions from the Chicago and Indianapolis urban areas (~125km north and east, of Bondville respectively) and regional emissions from electric utility facilities. Differences in Pb isotopes and element concentrations in precipitation corresponded to flow regime. Industrial sources from urban areas, and thorogenic Pb from coal use, could be differentiated from smelter emissions from Missouri by coupling Pb isotopes with variations in element ratios and relative mass factors. Using a three endmember mixing model based on Pb isotope ratio differences, industrial processes in urban airsheds contributed 56±19%, smelters in southeast Missouri 26±13%, and coal combustion 18±7%, of the Pb in precipitation collected in Bondville in the mid-1990s. Copyright © 2012 Elsevier B.V. All rights reserved.

Large angle tracking and high discriminating tracking in nuclear emulsion

International Nuclear Information System (INIS)

Matsuo, Tomokazu; Shibuya, Hiroshi; Ogawa, Satoru; Fukuda, Tsutomu; Mikado, Shoji

2015-01-01

Nuclear emulsion is a high resolution and re-analyzable detector. Conventional “Track Selector” which have angle acceptance |tan θ|<0.6 are widely used to find tracks in emulsion. We made a new track selector “Fine Track Selector” (FTS) which has large angle acceptance and high discriminating ability. The FTS reduces fake tracks using new algorithms, navigation etc. FTS also keeps finding efficiency of tracks around 90% in an angle range of |tan θ| < 3.5. FTS was applied to the τ candidate in OPERA and no additional tracks found. FTS will be useful to our new J-PARC emulsion experiment.

Track structure in biological models.

Science.gov (United States)

Curtis, S B

1986-01-01

High-energy heavy ions in the galactic cosmic radiation (HZE particles) may pose a special risk during long term manned space flights outside the sheltering confines of the earth's geomagnetic field. These particles are highly ionizing, and they and their nuclear secondaries can penetrate many centimeters of body tissue. The three dimensional patterns of ionizations they create as they lose energy are referred to as their track structure. Several models of biological action on mammalian cells attempt to treat track structure or related quantities in their formulation. The methods by which they do this are reviewed. The proximity function is introduced in connection with the theory of Dual Radiation Action (DRA). The ion-gamma kill (IGK) model introduces the radial energy-density distribution, which is a smooth function characterizing both the magnitude and extension of a charged particle track. The lethal, potentially lethal (LPL) model introduces lambda, the mean distance between relevant ion clusters or biochemical species along the track. Since very localized energy depositions (within approximately 10 nm) are emphasized, the proximity function as defined in the DRA model is not of utility in characterizing track structure in the LPL formulation.

EVOLUTIONARY TRACKS OF TRAPPED, ACCRETING PROTOPLANETS: THE ORIGIN OF THE OBSERVED MASS-PERIOD RELATION

International Nuclear Information System (INIS)

Hasegawa, Yasuhiro; Pudritz, Ralph E.

2012-01-01

The large number of observed exoplanets (∼>700) provides important constraints on their origin as deduced from the mass-period diagram of planets. The most surprising features in the diagram are (1) the (apparent) pileup of gas giants at a period of ∼500 days (∼1 AU) and (2) the so-called mass-period relation, which indicates that planetary mass is an increasing function of orbital period. We construct the evolutionary tracks of growing planets at planet traps in evolving protoplanetary disks and show that they provide a good physical understanding of how these observational properties arise. The fundamental feature of our model is that inhomogeneities in protoplanetary disks give rise to multiple (up to 3) trapping sites for rapid (type I) planetary migration of planetary cores. The viscous evolution of disks results in the slow radial movement of the traps and their cores from large to small orbital periods. In our model, the slow inward motion of planet traps is coupled with the standard core accretion scenario for planetary growth. As planets grow, type II migration takes over. Planet growth and radial movement are ultimately stalled by the dispersal of gas disks via photoevaporation. Our model makes a number of important predictions: that distinct sub-populations of planets that reflect the properties of planet traps where they have grown result in the mass-period relation, that the presence of these sub-populations naturally explains a pileup of planets at ∼1 AU, and that evolutionary tracks from the ice line do put planets at short periods and fill an earlier claimed p lanet desert — a sparse population of planets in the mass-semimajor axis diagram.

Passive target tracking using marginalized particle filter

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A marginalized particle filtering(MPF)approach is proposed for target tracking under the background of passive measurement.Essentially,the MPF is a combination of particle filtering technique and Kalman filter.By making full use of marginalization,the distributions of the tractable linear part of the total state variables are updated analytically using Kalman filter,and only the lower-dimensional nonlinear state variable needs to be dealt with using particle filter.Simulation studies are performed on an illustrative example,and the results show that the MPF method leads to a significant reduction of the tracking errors when compared with the direct particle implementation.Real data test results also validate the effectiveness of the presented method.

Influence of tracks densities in solid state nuclear track detectors

International Nuclear Information System (INIS)

Guedes O, S.; Hadler N.; Lunes, P.; Saenz T, C.

1996-01-01

When Solid State Nuclear Track Detectors (SSNTD) is employed to measure nuclear tracks produced mainly by fission fragments and alpha particles, it is considered that the tracks observation work is performed under an efficiency, ε 0 , which is independent of the track density (number of tracks/area unit). There are not published results or experimental data supporting such an assumption. In this work the dependence of ε 0 with track density is studied basing on experimental data. To perform this, pieces of CR-39 cut from a sole 'mother sheet' were coupled to thin uranium films for different exposition times and the resulting ratios between track density and exposition time were compared. Our results indicate that ε 0 is constant for track densities between 10 3 and 10 5 cm -2 . At our etching conditions track overlapping makes impossible the counting for densities around 1.7 x 10 5 cm -2 . For track densities less than 10 3 cm -2 , ε 0 , was not observed to be constant. (authors). 4 refs., 2 figs

How to Simply Demonstrate Diamagnetic Levitation with Pencil Lead

Science.gov (United States)

Koudelkova, Vera

2016-01-01

A new simple arrangement how to demonstrate diamagnetic levitation is presented. It uses pencil lead levitating in a track built from neodymium magnets. This arrangement can also be used as a classroom experiment.

Liquid nitrogen enhancement of partially annealed fission tracks in glass

International Nuclear Information System (INIS)

Pilione, L.J.; Gold, D.P.

1976-01-01

It is known that the number density of fission tracks in solids is reduced if the sample is heated before chemical etching, and the effect of annealing must be allowed for before an age can be assigned to the sample. The extent of annealing can be determined by measuring the reduction of track parameters (diameter and/or length) and comparison with unannealed tracks. Correct ages can be obtained by careful calibration studies of track density reduction against track diameter or length reduction at different annealing temperatures and times. For crystallised minerals, however, the resulting correction techniques are not generally valid. In the experimental work described glass samples were partially annealed and then immersed in liquid N 2 for various periods, and it was shown that the properties of the glass and the track parameters could be altered so as to observe tracks that would normally be erased by annealing. The results of track density measurements against liquid N 2 immersion times are shown graphically. A gain of about 40% was achieved after 760 hours immersion time. The size of the tracks was not noticeably affected by the immersion. It was thought that thermal shock might be the cause of the track enhancement, but it was found that repeated immersion for about 2 hours did not lead to an increase in track density. Other studies suggest that the mechanism that erases the tracks through annealing may be partially reversed when the temperature of the sample is significantly lowered for a sufficient length of time. Further work is under way to find whether or not the process of enhancement is a reversal of the annealing process. Similar enhancement effects using liquid N 2 have been observed for d-particle tracks in polycarbonate detectors. (U.K.)

Track reconstruction for the P2 experiment

Energy Technology Data Exchange (ETDEWEB)

Tyukin, Alexey [JGU, Mainz (Germany); Collaboration: P2-Collaboration

2016-07-01

The P2 experiment at the future MESA accelerator in Mainz will measure elastically scattered electrons from a hydrogen or lead target in order to determine the parity violating asymmetry for different beam polarisations, which is created due to the weak charge of the target. The asymmetry can provide access to the Weinberg angle and the neutron skin of heavy nuclei. These quantities depend heavily on the momentum transfer Q{sup 2}, thus a reconstruction of single electron tracks in an inhomogeneous magnetic field is necessary. For this, the P2 detector will have four tracking planes of thin high voltage monolithic active pixel sensors (HV-MAPS). The scattered electrons propagate through a magnetic field and hit all four planes. In order to fit the hit positions the General Broken Lines method is used. As a fast propagator, a variation of the Runge-Kutta algorithm is applied, which solves the equation of motion in an inhomogeneous magnetic field numerically, such that the final state momentum and scattering angle can be reconstructed. The initial momentum and incident angle can vary strongly due to the thickness of the target, limiting the reconstruction quality. The average single track Q{sup 2} value of 0.006 GeV{sup 2}/c{sup 2} can be reconstructed with about 4 % uncertainty in a first analysis of the Geant4 simulation, leading to a high total precision due to large electron numbers in the experiment.

ACTS: from ATLAS software towards a common track reconstruction software

Science.gov (United States)

Gumpert, C.; Salzburger, A.; Kiehn, M.; Hrdinka, J.; Calace, N.; ATLAS Collaboration

2017-10-01

Reconstruction of charged particles’ trajectories is a crucial task for most particle physics experiments. The high instantaneous luminosity achieved at the LHC leads to a high number of proton-proton collisions per bunch crossing, which has put the track reconstruction software of the LHC experiments through a thorough test. Preserving track reconstruction performance under increasingly difficult experimental conditions, while keeping the usage of computational resources at a reasonable level, is an inherent problem for many HEP experiments. Exploiting concurrent algorithms and using multivariate techniques for track identification are the primary strategies to achieve that goal. Starting from current ATLAS software, the ACTS project aims to encapsulate track reconstruction software into a generic, framework- and experiment-independent software package. It provides a set of high-level algorithms and data structures for performing track reconstruction tasks as well as fast track simulation. The software is developed with special emphasis on thread-safety to support parallel execution of the code and data structures are optimised for vectorisation to speed up linear algebra operations. The implementation is agnostic to the details of the detection technologies and magnetic field configuration which makes it applicable to many different experiments.

Automated tracking and quantification of angiogenic vessel formation in 3D microfluidic devices.

Science.gov (United States)

Wang, Mengmeng; Ong, Lee-Ling Sharon; Dauwels, Justin; Asada, H Harry

2017-01-01

Angiogenesis, the growth of new blood vessels from pre-existing vessels, is a critical step in cancer invasion. Better understanding of the angiogenic mechanisms is required to develop effective antiangiogenic therapies for cancer treatment. We culture angiogenic vessels in 3D microfluidic devices under different Sphingosin-1-phosphate (S1P) conditions and develop an automated vessel formation tracking system (AVFTS) to track the angiogenic vessel formation and extract quantitative vessel information from the experimental time-lapse phase contrast images. The proposed AVFTS first preprocesses the experimental images, then applies a distance transform and an augmented fast marching method in skeletonization, and finally implements the Hungarian method in branch tracking. When applying the AVFTS to our experimental data, we achieve 97.3% precision and 93.9% recall by comparing with the ground truth obtained from manual tracking by visual inspection. This system enables biologists to quantitatively compare the influence of different growth factors. Specifically, we conclude that the positive S1P gradient increases cell migration and vessel elongation, leading to a higher probability for branching to occur. The AVFTS is also applicable to distinguish tip and stalk cells by considering the relative cell locations in a branch. Moreover, we generate a novel type of cell lineage plot, which not only provides cell migration and proliferation histories but also demonstrates cell phenotypic changes and branch information.

Alterations of lead speciation by sulfate from addition of flue gas desulfurization gypsum (FGDG) in two contaminated soils

Science.gov (United States)

This is the first study to evaluate the potential application of FGDG as an in situ Pb stabilizer in contaminated soils with two different compositions and to explain the underlying mechanisms. A smelter Pb contaminated soil (SM-soil), rich in ferrihydrite bound Pb (FH-Pb), ceru...

Symplectic Tracking of Multi-Isotopic Heavy-Ion Beams in SixTrack

CERN Document Server

Hermes, Pascal; De Maria, Riccardo

2016-01-01

The software SixTrack provides symplectic proton tracking over a large number of turns. The code is used for the tracking of beam halo particles and the simulation of their interaction with the collimators to study the efficiency of the LHC collimation system. Tracking simulations for heavy-ion beams require taking into account the mass to charge ratio of each particle because heavy ions can be subject to fragmentation at their passage through the collimators. In this paper we present the derivation of a Hamiltonian for multi-isotopic heavy-ion beams and symplectic tracking maps derived from it. The resulting tracking maps were implemented in the tracking software SixTrack. With this modification, SixTrack can be used to natively track heavy-ion beams of multiple isotopes through a magnetic accelerator lattice.

The seam visual tracking method for large structures

Science.gov (United States)

Bi, Qilin; Jiang, Xiaomin; Liu, Xiaoguang; Cheng, Taobo; Zhu, Yulong

2017-10-01

In this paper, a compact and flexible weld visual tracking method is proposed. Firstly, there was the interference between the visual device and the work-piece to be welded when visual tracking height cannot change. a kind of weld vision system with compact structure and tracking height is researched. Secondly, according to analyze the relative spatial pose between the camera, the laser and the work-piece to be welded and study with the theory of relative geometric imaging, The mathematical model between image feature parameters and three-dimensional trajectory of the assembly gap to be welded is established. Thirdly, the visual imaging parameters of line structured light are optimized by experiment of the weld structure of the weld. Fourth, the interference that line structure light will be scatters at the bright area of metal and the area of surface scratches will be bright is exited in the imaging. These disturbances seriously affect the computational efficiency. The algorithm based on the human eye visual attention mechanism is used to extract the weld characteristics efficiently and stably. Finally, in the experiment, It is verified that the compact and flexible weld tracking method has the tracking accuracy of 0.5mm in the tracking of large structural parts. It is a wide range of industrial application prospects.

Predictors of environmental lead exposure among pregnant women – a prospective cohort study in Poland

Directory of Open Access Journals (Sweden)

Kinga Polańska

2014-03-01

Full Text Available Blood lead levels (BLL in women of child-bearing age have been decreasing in recent decades, but still remains a concern for long-term effects of child psychomotor development. The aim of the study was to characterize lead exposure among Polish pregnant women and assess the relationship between BLL and selected socio-demographic, economic and lifestyle factors. The study population consisted of 594 pregnant women who had been the subjects of the prospective Polish Mother and Child Cohort Study (REPRO_PL. The women were interviewed three times during pregnancy (once in each trimester. Lead concentration in the blood collected during the second trimester of pregnancy was analyzed using graphite furnace atomic absorption spectrometry (GF-AAS, or inductively coupled plasma mass spectrometry (ICP-MS. Active and passive smoking was analyzed by the cotinine level in saliva using liquid chromatography with tandem mass spectrometry (LC-MS/MS. The lead level in the blood ranged from 0.3 – 5.7 μg/dL, with a geometric mean (GM of 1.1 μg/dL (GSD }0.2 μg/dL. Statistically significant associations were found between BLL and factors such as maternal age (β=0.01; p=0.02, education (β=0.08; p=0.04 and prepregnancy BMI (β=0.1; p=0.001. Additionally, BLL increased with increasing cotinine level in saliva (β=0.02; p=0.06 and decreased with the increasing distance from the copper smelter (β=-0.1; p=0.009. Public health interventions, especially in regions with a higher level of exposure to lead, among women with lower SES and among smokers, are still reasonable.

Bioaccumulation of heavy metals, metalloids, and chlorine in ectomycorrhizae from smelter-polluted area.

Science.gov (United States)

Cejpková, Jaroslava; Gryndler, Milan; Hršelová, Hana; Kotrba, Pavel; Řanda, Zdeněk; Synková, Iva; Borovička, Jan

2016-11-01

Ectomycorrhizal (ECM) fungi contribute to the survival of host trees on metal-rich soils by reducing the transfer of toxic metals into roots. However, little is known about the ability of ECM fungi to accumulate elements in ectomycorrhizae (ECMs). Here we report Ag, As, Cd, Cl, Cu, Sb, V, and Zn contents in wild-grown Norway spruce ECMs collected in a smelter-polluted area at Lhota near Příbram, Czech Republic. The ECMs data were compared with the element concentrations determined in the corresponding non-mycorrhizal fine roots, soils, and soil extracts. Bioaccumulation factors were calculated to differentiate the element accumulation ability of ECMs inhabited by different mycobionts, which were identified by ITS rDNA sequencing. Among the target elements, the highest contents were observed for Ag, Cl, Cd, and Zn; Imleria badia ECMs showed the highest capability to accumulate these elements. ECMs of Amanita muscaria, but not of other species, accumulated V. The analysis of the proportions of I. badia and A. muscaria mycelia in ECMs by using species-specific quantitative real-time PCR revealed variable extent of the colonization of roots, with median values close to 5% (w/w). Calculated Ag, Cd, Zn and Cl concentrations in the mycelium of I. badia ECMs were 1 680, 1 510, 2 670, and 37,100 mg kg -1 dry weight, respectively, indicating substantial element accumulation capacity of hyphae of this species in ECMs. Our data strengthen the idea of an active role of ECM fungi in soil-fungal-plant interactions in polluted environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

PolarTrack: Optical Outside-In Device Tracking that Exploits Display Polarization

DEFF Research Database (Denmark)

Rädle, Roman; Jetter, Hans-Christian; Fischer, Jonathan

2018-01-01

PolarTrack is a novel camera-based approach to detecting and tracking mobile devices inside the capture volume. In PolarTrack, a polarization filter continuously rotates in front of an off-the-shelf color camera, which causes the displays of observed devices to periodically blink in the camera feed....... The periodic blinking results from the physical characteristics of current displays, which shine polarized light either through an LC overlay to produce images or through a polarizer to reduce light reflections on OLED displays. PolarTrack runs a simple detection algorithm on the camera feed to segment...... displays and track their locations and orientations, which makes PolarTrack particularly suitable as a tracking system for cross-device interaction with mobile devices. Our evaluation of PolarTrack's tracking quality and comparison with state-of-the-art camera-based multi-device tracking showed a better...

Relative potentials of concentrating and two-axis tracking flat-plate photovoltaic arrays for central-station applications

Science.gov (United States)

Borden, C. S.; Schwartz, D. L.

1984-01-01

The purpose of this study is to assess the relative economic potentials of concenrating and two-axis tracking flat-plate photovoltaic arrays for central-station applications in the mid-1990's. Specific objectives of this study are to provide information on concentrator photovoltaic collector probabilistic price and efficiency levels to illustrate critical areas of R&D for concentrator cells and collectors, and to compare concentrator and flat-plate PV price and efficiency alternatives for several locations, based on their implied costs of energy. To deal with the uncertainties surrounding research and development activities in general, a probabilistic assessment of commercially achievable concentrator photovoltaic collector efficiencies and prices (at the factory loading dock) is performed. The results of this projection of concentrator photovoltaic technology are then compared with a previous flat-plate module price analysis (performed early in 1983). To focus this analysis on specific collector alternatives and their implied energy costs for different locations, similar two-axis tracking designs are assumed for both concentrator and flat-plate options.

Lead Contamination and Source Characterization in Soils Around a Lead-Zinc Smelting Plant in a Near-Urban Environment in Baoji, China.

Science.gov (United States)

Deng, Wenbo; Li, Xuxiang; An, Zhisheng; Yang, Liu

2016-11-01

Economic reforms in China since 1978 have promoted nationwide socioeconomic advancement but led to a considerable amount of environmental pollution. The distribution and sources of Pb in a typical peri-urban industrial part of Baoji, China, were assessed by determining the Pb contents and isotopic compositions in 52 topsoil samples from the study area. The topsoil samples were polluted averagely with 40.88 mg Pb kg -1 , was 1.86 times higher than the Pb content of local background soil (22.04 mg kg -1 ). Pb isotopic compositions were determined by analyzing samples prepared using total digestion and acid extraction methods. Radiogenic isotopes contributed more to the Pb concentrations in the acid extracts than in the total digests. This was shown by the 207/206 Pb and 208/206 Pb ratios, which were 0.845-0.88 and 2.088-2.128, respectively, in the acid extracts and 0.841-0.875 and 2.086-2.125, respectively, in the total digests. This indicates that anthropogenic sources of Pb could be identified more sensitively in acid extracts than in total digests. The Pb isotope ratios showed that burning coal and smelting ore are the predominant anthropogenic sources of Pb in the study area, i.e., a lead-zinc smelter and a coking plant are major sources of Pb in the study area.

Occlusion Handling in Videos Object Tracking: A Survey

International Nuclear Information System (INIS)

Lee, B Y; Liew, L H; Cheah, W S; Wang, Y C

2014-01-01

Object tracking in video has been an active research since for decades. This interest is motivated by numerous applications, such as surveillance, human-computer interaction, and sports event monitoring. Many challenges related to tracking objects still remain, this can arise due to abrupt object motion, changing appearance patterns of objects and the scene, non-rigid object structures and most significant are occlusion of tracked object be it object-to-object or object-to-scene occlusions. Generally, occlusion in object tracking occur under three situations: self-occlusion, inter-object occlusion by background scene structure. Self-occlusion occurs most frequently while tracking articulated objects when one part of the object occludes another. Inter-object occlusion occurs when two objects being tracked occlude each other whereas occlusion by the background occurs when a structure in the background occludes the tracked objects. Typically, tracking methods handle occlusion by modelling the object motion using linear and non-linear dynamic models. The derived models will be used to continuously predicting the object location when a tracked object is occluded until the object reappears. Example of these method are Kalman filtering and Particle filtering trackers. Researchers have also utilised other features to resolved occlusion, for example, silhouette projections, colour histogram and optical flow. We will present some result from a previously conducted experiment when tracking single object using Kalman filter, Particle filter and Mean Shift trackers under various occlusion situation in this paper. We will also review various other occlusion handling methods that involved using multiple cameras. In a nutshell, the goal of this paper is to discuss in detail the problem of occlusion in object tracking and review the state of the art occlusion handling methods, classify them into different categories, and identify new trends. Moreover, we discuss the important

Occlusion Handling in Videos Object Tracking: A Survey

Science.gov (United States)

Lee, B. Y.; Liew, L. H.; Cheah, W. S.; Wang, Y. C.

2014-02-01

Object tracking in video has been an active research since for decades. This interest is motivated by numerous applications, such as surveillance, human-computer interaction, and sports event monitoring. Many challenges related to tracking objects still remain, this can arise due to abrupt object motion, changing appearance patterns of objects and the scene, non-rigid object structures and most significant are occlusion of tracked object be it object-to-object or object-to-scene occlusions. Generally, occlusion in object tracking occur under three situations: self-occlusion, inter-object occlusion by background scene structure. Self-occlusion occurs most frequently while tracking articulated objects when one part of the object occludes another. Inter-object occlusion occurs when two objects being tracked occlude each other whereas occlusion by the background occurs when a structure in the background occludes the tracked objects. Typically, tracking methods handle occlusion by modelling the object motion using linear and non-linear dynamic models. The derived models will be used to continuously predicting the object location when a tracked object is occluded until the object reappears. Example of these method are Kalman filtering and Particle filtering trackers. Researchers have also utilised other features to resolved occlusion, for example, silhouette projections, colour histogram and optical flow. We will present some result from a previously conducted experiment when tracking single object using Kalman filter, Particle filter and Mean Shift trackers under various occlusion situation in this paper. We will also review various other occlusion handling methods that involved using multiple cameras. In a nutshell, the goal of this paper is to discuss in detail the problem of occlusion in object tracking and review the state of the art occlusion handling methods, classify them into different categories, and identify new trends. Moreover, we discuss the important

Properties of Polyethylene Naphthalate Track Membranes

CERN Document Server

Akimenko, S N; Orelovich, O L; Maekawa, J; Ioshida, M; Apel, P Yu

2002-01-01

Basic characteristics of track membranes made of polyethylene naphthalate (which is a polyester synthesized from dimethyl naphthalate and ethylene glycol) are studied and presented. Polyethylene naphthalate possesses some properties (mechanical strength, thermal and chemical stability), which make this polymer a promising material for the production of track membranes. Water flow rate and air flow rate characteristics, burst strength, wettability, and amount of extractables are determined. Surface structure and pore structure are examined using scanning electron microscopy. It is found that the pores in the membranes are cylindrical in shape. The measured water and air flow rates follow known theoretical relations for the transport in narrow capillaries. The burst strength of polyethylene naphthalate membranes is found to be similar to that of polyethylene terephthalate track membranes. Polyethylene naphthalate track membranes can be categorized as moderately hydrophilic. Being treated with boiling water, pol...

Improvements to ATLAS Track Reconstruction for Run-II

CERN Document Server

Cairo, Valentina Maria; The ATLAS collaboration

2015-01-01

Run-II of the LHC will provide new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. In addition, the Insertable B-layer (IBL) is a fourth pixel layer, which has been inserted at the centre of ATLAS during the shutdown of the LHC. We will discuss improvements to track reconstruction developed during the two year shutdown of the LHC. These include novel techniques developed to improve the performance in the dense cores of jets, optimisation for the expected conditions, and a big software campaign which lead to more than a factor of three decrease in the CPU time needed to process each recorded event.

SU-E-T-494: Influence of Proton Track-Cell Nucleus Incidence Angle On Relative Biological Effectiveness

Energy Technology Data Exchange (ETDEWEB)

Pater, P; Backstrom, G; Enger, S; Seuntjens, J; El Naqa, I [McGill University, Montreal, Quebec (Canada); Villegas, F; Ahnesjo, A [Uppsala University, Uppsala (Sweden)

2015-06-15

Purpose: To explain a Monte Carlo (MC) simulation artifact whereby differences in relative biological effectiveness (RBE) in the induction of initial double strand breaks are observed as a function of the proton track incidence angles in a geometric cell nucleus model. Secondly, to offer an alternative isotropic irradiation procedure to mitigate this effect. Methods: MC tracks of 1 MeV protons were generated in an event-by-event mode. They were overlaid on a cylindrical model of a cell nucleus containing 6×109 nucleotide base pairs. The tracks incidence angle θ with respect to the cell nucleus’s axis was varied in 10 degrees intervals, each time generating one hundred fractions of ∼2 Gy. Strand breaks were scored in the modeled DNA sugar-phosphate groups and further sub-classified into single or double strand breaks (ssbs or dsbs). For each angle, an RBE for the induction of initial dsbs with reference to Co-60 was calculated. Results: Our results show significant angular dependencies of RBE, with maximum values for incidence angles parallel to the nucleus central axis. Further examination shows that the higher cross-sections for the creation of dsbs is due to the preferential alignment of tracks with geometrical sub-parts of the cell nucleus model, especially the nucleosomes containing the sugar-phosphate groups. To alleviate the impact of this simulation artifact, an average RBE was calculated with a procedure based on a weighted sampling of the angular data. Conclusion: This work demonstrates a possible numerical artifact in estimated RBE if the influence of the particle incidence angle is not correctly taken into account. A correction procedure is presented to better conform the simulations to real-life experimental conditions. We would like to acknowledge support from the Fonds de recherche du Quebec Sante (FRQS), from the CREATE Medical Physics Research Training Network grant (number 432290) of NSERC, support from NSERC under grants RGPIN 397711-11 and

Dual track or academic route for auditors: does it matter?

NARCIS (Netherlands)

Jonker, N.; van Ophem, H.; Hartog, J.

2006-01-01

In the Netherlands auditors can be trained in a part-time educational track in which students combine working and studying or in a full-time educational track. The former training is relatively firm-specific whereas the latter training is relatively general. Applying human capital theory, we expect

Remediation of contaminated agricultural soils near a former Pb/Zn smelter in Austria: Batch, pot and field experiments

International Nuclear Information System (INIS)

Friesl, W.; Friedl, J.; Platzer, K.; Horak, O.; Gerzabek, M.H.

2006-01-01

Metal contaminated crops from contaminated soils are possible hazards for the food chain. The aim of this study was to find practical and cost-effective measures to reduce metal uptake in crops grown on metal contaminated soils near a former metal smelter in Austria. Metal-inefficient cultivars of crop plants commonly grown in the area were investigated in combination with in-situ soil amendments. A laboratory batch experiment using 15 potential amendments was used to select 5 amendments to treat contaminated soil in a pot study using two Barley (Hordeum vulgare L.) cultivars that differed in their ability to accumulate cadmium. Results from this experiment identified 3 of these amendments for use in a field trial. In the pot experiment a reduction in ammonium nitrate extractable Cd (<41%) and Pb (<49%) compared to the controls was measured, with a concurrent reduction of uptake into barley grain (Cd < 62%, Pb < 68%). In the field extractable fractions of Cd, Pb, and Zn were reduced by up to 96%, 99%, and 99%, respectively in amended soils. - Gravel sludge and red mud, combined with metal-excluding cultivars, can improve contaminated land

Urban quality of life and industrial project management: the case of Alcan aluminium smelter in Alma, Quebec, Canada

International Nuclear Information System (INIS)

Simard, M.

2003-01-01

This quality-of-life study involving the population of Alma (30 126 inhabitants) is part of a five-year, multidisciplinary research program entitled 'Modelisation du suivi des impacts sociaux de l'aluminerie Alma'. The goal of this research program is to document the social impacts arising from the establishment of the Alcan industrial mega-complex in Alma (see Map 1). The Alma smelter began operation in 2001. It employs 865 people and has a production capacity of 407 000 MT of aluminium ingots. The research program is being carried out in parallel with the project, rather than retroactively. Thus, various thematic reports have been published on topics such as the project's economic spin-off and changes in the housing and transportation sectors. More specifically, this study aims to gauge the perceptions of Alma residents regarding their quality of life as stakeholders. In order to ensure that the study produced a more accurate indication of the community's evolution and to tie the study in with the various phases of the implementation of this industrial mega-project, it was conducted in three parts, i.e., in 1998, 2000 and 2002, corresponding to the planning, construction and operation phases. (author)

Tube collector with integrated tracking parabolic concentrator

Energy Technology Data Exchange (ETDEWEB)

Grass, C.; Benz, N.; Hacker, Z.; Timinger, A. [ZAE Bayern, Bavarian Centre for Applied Energy Research, Muenchen (Germany)

2000-07-01

Low concentrating CPC collectors usually do not track the sun and are mounted in east-west direction with a latitude dependent slope angle. They are most suitable for maximum working temperatures up to 200 250 deg. C. We present a novel evacuated tube-collector with a trough-like concentrating mirror. Single-axis tracking of the mirror is realized with a magnetic mechanism. The mirror is mounted inside the evacuated tube and hence protected from environmental influences. One axis tracking in combination with a small acceptance angle allows for higher concentration as compared to non-tracking concentrating collectors. Ray-tracing analysis shows a half acceptance angle of about 5 deg. at a geometrical concentration ratio of 3.2. The losses of evacuated tube collectors are dominated by the radiation losses of the absorber. Hence, reducing the absorber size can lead to higher efficiencies at high operating temperature levels. With the presented collector we aim for operating temperatures up to 400 deg. C. At temperatures of 300 deg. C we expect efficiencies of 65 %. This allows for application in industrial process heat generation, high efficient solar cooling and power generation. A first prototype was tested at the ZAE Bayern. The optical efficiency was measured to be 75 %. (au)

A Systematic Review of Pliance, Tracking, and Augmenting

NARCIS (Netherlands)

Kissi, Ama; Hughes, Sean; Mertens, Gaëtan; Barnes-Holmes, Dermot; De Houwer, Jan; Crombez, Geert

Within relational frame theory, a distinction has been made between three types of rule-governed behavior known as pliance, tracking, and augmenting. This review examined whether there is support for the concepts of pliance, tracking, and augmenting in the experimental analysis of behavior; whether

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

Science.gov (United States)

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

1999-07-01

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

Representation of Northern Hemisphere winter storm tracks in climate models

Energy Technology Data Exchange (ETDEWEB)

Greeves, C.Z.; Pope, V.D.; Stratton, R.A.; Martin, G.M. [Met Office Hadley Centre for Climate Prediction and Research, Exeter (United Kingdom)

2007-06-15

Northern Hemisphere winter storm tracks are a key element of the winter weather and climate at mid-latitudes. Before projections of climate change are made for these regions, it is necessary to be sure that climate models are able to reproduce the main features of observed storm tracks. The simulated storm tracks are assessed for a variety of Hadley Centre models and are shown to be well modelled on the whole. The atmosphere-only model with the semi-Lagrangian dynamical core produces generally more realistic storm tracks than the model with the Eulerian dynamical core, provided the horizontal resolution is high enough. The two models respond in different ways to changes in horizontal resolution: the model with the semi-Lagrangian dynamical core has much reduced frequency and strength of cyclonic features at lower resolution due to reduced transient eddy kinetic energy. The model with Eulerian dynamical core displays much smaller changes in frequency and strength of features with changes in horizontal resolution, but the location of the storm tracks as well as secondary development are sensitive to resolution. Coupling the atmosphere-only model (with semi-Lagrangian dynamical core) to an ocean model seems to affect the storm tracks largely via errors in the tropical representation. For instance a cold SST bias in the Pacific and a lack of ENSO variability lead to large changes in the Pacific storm track. Extratropical SST biases appear to have a more localised effect on the storm tracks. (orig.)

Track reconstruction at the ILC: the ILD tracking software

International Nuclear Information System (INIS)

Gaede, Frank; Aplin, Steven; Rosemann, Christoph; Voutsinas, Georgios; Glattauer, Robin

2014-01-01

One of the key requirements for Higgs physics at the International Linear Collider ILC is excellent track reconstruction with very good momentum and impact parameter resolution. ILD is one of the two detector concepts at the ILC. Its central tracking system comprises of an outer Si-tracker, a highly granular TPC, an intermediate silicon tracker and a pixel vertex detector, and it is complemented by silicon tracking disks in the forward direction. Large hit densities from beam induced coherent electron-positron pairs at the ILC pose an additional challenge to the pattern recognition algorithms. We present the recently developed new ILD tracking software, the pattern recognition algorithms that are using clustering techniques, Cellular Automatons and Kalman filter based track extrapolation. The performance of the ILD tracking system is evaluated using a detailed simulation including dead material, gaps and imperfections.

A Pilot Study of Children's Blood Lead Levels in Mount Isa, Queensland.

Science.gov (United States)

Green, Donna; Sullivan, Marianne; Cooper, Nathan; Dean, Annika; Marquez, Cielo

2017-12-13

Mount Isa, Queensland, is one of three Australian cities with significant lead emissions due to nonferrous mining and smelting. Unlike the two other cities with lead mines or smelters, Mount Isa currently has no system of annual, systematic, community-wide blood lead level testing; and testing rates among Indigenous children are low. In previous screenings, this group of children has been shown to have higher average blood lead levels than non-Indigenous children. The first aim of this study was to assess whether parents and children would participate in less invasive, rapid point-of-care capillary testing. The second aim was to measure blood lead levels among a range of children that roughly reflected the percentage of the Indigenous/non-Indigenous population. This pilot study is based on a convenience sample of children between the ages of 12 and 83 months who were recruited to participate by staff at a Children and Family Centre. Over three half-days, 30 children were tested using capillary blood samples and the LeadCare II Point-of-Care testing system. Rapid point-of-care capillary testing was well tolerated by the children. Of 30 children tested, 40% ( n = 12) had blood lead levels ≥5 µg/dL and 10% had levels ≥10 µg/dL. The highest blood lead level measured was 17.3 µg/dL. The percentage of children with blood lead levels ≥5 µg/dL was higher among Indigenous children compared to non-Indigenous (64.2% compared to 18.8%) as was the geometric mean level (6.5 (95% CI, 4.7, 9.2) versus 2.4 (95% CI, 1.8, 3.1)), a statistically significant difference. Though based on a small convenience sample, this study identified 12 children (40%) of the sample with blood lead levels ≥5 µg/dL. Due to historical and ongoing heavy metal emissions from mining and smelting in Mount Isa, we recommend a multi-component program of universal blood lead level testing, culturally appropriate follow-up and intervention for children who are identified with blood lead levels ≥5

Tracking clinical competencies on the web.

Science.gov (United States)

Hobbs, Dan L

2005-01-01

The American Registry of Radiologic Technologists (ARRT) has defined several core examinations that student radiographers must perform to demonstrate competency. Furthermore, the ARRT has left the method of tracking competency exams to educators. This article describes a Web-based system that can be used to track clinical competencies. The pedagogy employed in designing a meaningful and successful Web site to track competencies can be overwhelming. Considerations include selecting software, the design and implementation process, and providing security to protect confidential information. The Web-based system described in this article is innovative, sensible and relatively easy to adopt. This tracking method provides faculty members with instantaneous access and a quick review of the student's competency examinations. Students' competency information for the entire program is contained in 1 electronic file. With minor modification, the system can be used in a variety of educational and administrative settings.

FAST-TRACK HIP AND KNEE ARTHROPLASTY (LITERATURE REVIEW

Directory of Open Access Journals (Sweden)

A. M. Ageenko

2017-01-01

Full Text Available In the present paper the authors discuss the history of fast-track formation, its development and current status. Fast-track advantages in comparison to other rehabilitation options are analyzed. The focus is placed on methods of accelerated rehabilitation after total hip and knee arthroplasty in the leading European and American clinics. Fast-track protocols of surgical centers of Denmark and Hospital for special surgery in the US are described, factors that determine time of hospital stay after total hip and knee arthroplasty are considered, predictors of hospital stay and patients satisfaction after the surgery are examined. The paper reflects the results of the comparison of frequency of thromboembolic and other complications as well as readmission rate after traditional rehabilitation and after fast-track. The paper considers fast-track in bilateral total knee replacement. The authors conclude that further research on acceleration of rehabilitation and reduction of hospital stay after total hip and knee arthroplasty needs to be focused on the optimization of pain relief, especially after discharge, blood preservation techniques, supplementation of fluids loss and strengthening of muscles. Literature analysis demonstrated that the implementation of the Protocol for accelerated recovery after joint arthroplasty in Russia is at an insufficient level. Data of foreign multicenter studies during recent years indicate a high efficacy and safety of this technique in different groups of patients.

Tracking in Dense Environments for the HL-LHC ATLAS Detector

CERN Document Server

Cormier, Felix; The ATLAS collaboration

2018-01-01

Tracking in dense environments, such as in the cores of high-energy jets, will be key for new physics searches as well as measurements of the Standard Model at the High Luminosity LHC (HL-LHC). The HL-LHC will operate in challenging conditions with large radiation doses and high pile-up (up to $\\mu=200$). The current tracking detector will be replaced with a new all-silicon Inner Tracker for the Phase II upgrade of the ATLAS detector. In this talk, characterization of the HL-LHC tracker performance for collimated, high-density charged particles arising from high-momentum decays is presented. In such decays the charged-particle separations are of the order of the tracking detector granularity, leading to challenging reconstruction. The ability of the HL-LHC ATLAS tracker to reconstruct the tracks in such dense environments is discussed and compared to ATLAS Run-2 performance for a variety of relevant physics processes.

Radiation damage to DNA: The importance of track structure

International Nuclear Information System (INIS)

Hill, M.A.

1999-01-01

A wide variety of biological effects are induced by ionizing radiation, from cell death to mutations and carcinogenesis. The biological effectiveness is found to vary not only with the absorbed dose but also with the type of radiation and its energy, i.e., with the nature of radiation tracks. An overview is presented of some of the biological experiments using different qualities of radiation, which when compared with Monte Carlo track structure studies, have highlighted the importance of the localized spatial properties of stochastic energy deposition on the nanometer scale at or near DNA. The track structure leads to clustering of damage which may include DNA breaks, base damage etc., the complexity of the cluster and therefore its biological repairability varying with radiation type. The ability of individual tracks to produce clustered damage, and the subsequent biological response are important in the assessment of the risk associated with low-level human exposure. Recent experiments have also shown that biological response to radiation is not always restricted to the 'hit' cell but can sometimes be induced in 'un-hit' cells near by

Local tracking in the ATLAS muon spectrometer

CERN Document Server

Primor, David; Mikenberg, Giora

2007-01-01

The LHC, the largest hadron collider accelerator ever built, presents new challenges for scientists and engineers. With the anticipated luminosity of the LHC, it is expected to have as many as one billion total collisions per second, of which at most 10 to 100 per second might be of potential scientific interest. One of the two major, general-purpose experiments at LHC is called ATLAS. Since muons are one of the important signs of new physics, the need of their detection has lead to the construction of a stand- alone Muon Spectrometer. This system is located in a high radiation background environment (mostly neutrons and photons) which makes the muon tracking a very challenging task. The Muon Spectrometer consists of two types of precision chambers, the Monitor Drift Tube (MDT) chambers, and the Cathode Strip Chambers (CSC). In order to detect the muon and estimate its track parameters, it is very important to detect and precisely estimate its local tracks within the CSC and MDT chambers. Using advanced signa...

Fission tracks diameters in glasses

International Nuclear Information System (INIS)

Garzon Ruiperez, L.; Veiguela, J.

1974-01-01

Standard glass microscope slides have been irradiated with fission fragments from the uranium. The etching track conditions have been the same for the series, having changed the etching time only for each specimen. For each glass, a minimum of 250 measurements of the tracks diameters have been made, the distributions of which are the bimodal type. Diameters-etching dependence with time is roughly lineal. Energy determinations have been made with the help of the diameters-energy relations. The calculated values agree very well with the know ones. (author) [es

A Bayesian solution to multi-target tracking problems with mixed labelling

NARCIS (Netherlands)

Aoki, E.H.; Boers, Y.; Svensson, Lennart; Mandal, Pranab K.; Bagchi, Arunabha

In Multi-Target Tracking (MTT), the problem of assigning labels to tracks (track labelling) is vastly covered in literature and has been previously formulated using Bayesian recursion. However, the existing literature lacks an appropriate measure of uncertainty related to the assigned labels which

Shape tracking with occlusions via coarse-to-fine region-based sobolev descent

KAUST Repository

Yang, Yanchao

2015-05-01

We present a method to track the shape of an object from video. The method uses a joint shape and appearance model of the object, which is propagated to match shape and radiance in subsequent frames, determining object shape. Self-occlusions and dis-occlusions of the object from camera and object motion pose difficulties to joint shape and appearance models in tracking. They are unable to adapt to new shape and appearance information, leading to inaccurate shape detection. In this work, we model self-occlusions and dis-occlusions in a joint shape and appearance tracking framework. Self-occlusions and the warp to propagate the model are coupled, thus we formulate a joint optimization problem. We derive a coarse-to-fine optimization method, advantageous in tracking, that initially perturbs the model by coarse perturbations before transitioning to finer-scale perturbations seamlessly. This coarse-to-fine behavior is automatically induced by gradient descent on a novel infinite-dimensional Riemannian manifold that we introduce. The manifold consists of planar parameterized regions, and the metric that we introduce is a novel Sobolev metric. Experiments on video exhibiting occlusions/dis-occlusions, complex radiance and background show that occlusion/dis-occlusion modeling leads to superior shape accuracy. © 2014 IEEE.

Assessment of the pseudo-tracking approach for the calculation of material acceleration and pressure fields from time-resolved PIV: part II. Spatio-temporal filtering

Science.gov (United States)

van Gent, P. L.; Schrijer, F. F. J.; van Oudheusden, B. W.

2018-04-01

The present study characterises the spatio-temporal filtering associated with pseudo-tracking. A combined theoretical and numerical assessment is performed that uses the relatively simple flow case of a two-dimensional Taylor vortex as analytical test case. An additional experimental assessment considers the more complex flow of a low-speed axisymmetric base flow, for which time-resolved tomographic PIV measurements and microphone measurements were obtained. The results of these assessments show how filtering along Lagrangian tracks leads to amplitude modulation of flow structures. A cut-off track length and spatial resolution are specified to support future applications of the pseudo-tracking approach. The experimental results show a fair agreement between PIV and microphone pressure data in terms of fluctuation levels and pressure frequency spectra. The coherence and correlation between microphone and PIV pressure measurements were found to be substantial and almost independent of the track length, indicating that the low-frequency behaviour of the flow could be reproduced regardless of the track length. It is suggested that a spectral analysis can be used inform the selection of a suitable track length and to estimate the local error margin of reconstructed pressure values.

Robust online tracking via adaptive samples selection with saliency detection

Science.gov (United States)

Yan, Jia; Chen, Xi; Zhu, QiuPing

2013-12-01

Online tracking has shown to be successful in tracking of previously unknown objects. However, there are two important factors which lead to drift problem of online tracking, the one is how to select the exact labeled samples even when the target locations are inaccurate, and the other is how to handle the confusors which have similar features with the target. In this article, we propose a robust online tracking algorithm with adaptive samples selection based on saliency detection to overcome the drift problem. To deal with the problem of degrading the classifiers using mis-aligned samples, we introduce the saliency detection method to our tracking problem. Saliency maps and the strong classifiers are combined to extract the most correct positive samples. Our approach employs a simple yet saliency detection algorithm based on image spectral residual analysis. Furthermore, instead of using the random patches as the negative samples, we propose a reasonable selection criterion, in which both the saliency confidence and similarity are considered with the benefits that confusors in the surrounding background are incorporated into the classifiers update process before the drift occurs. The tracking task is formulated as a binary classification via online boosting framework. Experiment results in several challenging video sequences demonstrate the accuracy and stability of our tracker.

Nuclear track-based biosensors with the enzyme laccase

Energy Technology Data Exchange (ETDEWEB)

García-Arellano, H. [Departamento de Ciencias Ambientales, División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana-Lerma, Av. de las Garzas No. 10, Col. El Panteón, Lerma de Villada, Municipio de Lerma, Estado de México, C.P. 52005 (Mexico); Fink, D., E-mail: fink@xanum.uam.mx [Division de Ciencias Naturales e Ingeneria, Universidad Autónoma Metropolitana-Cuajimalpa, Artificios 40, Col. Hidalgo, Del. Álvaro Obregón C.P. 01120, México, D.F. (Mexico); Nuclear Physics Institute, 25068 Řež (Czech Republic); Muñoz Hernández, G. [Division de Ciencias Naturales e Ingeneria, Universidad Autónoma Metropolitana-Cuajimalpa, Artificios 40, Col. Hidalgo, Del. Álvaro Obregón C.P. 01120, México, D.F. (Mexico); Departamento de Fisica, Universidad Autónoma Metropolitana-Iztapalapa, PO Box 55-534, 09340 México, D.F. (Mexico); Vacík, J.; Hnatowicz, V. [Nuclear Physics Institute, 25068 Řež (Czech Republic); Alfonta, L. [Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Ben-Gurion University of the Negev, PO Box 653, Beer-Sheva 84105 (Israel)

2014-08-15

Highlights: • We construct a biosensor using polymer foils with laccase-clad etched nuclear tracks. • We use the biosensor for quantitation of phenolic compounds. • The biosensor can detect picomolar concentrations for some phenolic compounds. - Abstract: A new type of biosensors for detecting phenolic compounds is presented here. These sensors consist of thin polymer foils with laccase-clad etched nuclear tracks. The presence of suitable phenolic compounds in the sensors leads to the formation of enzymatic reaction products in the tracks, which differ in their electrical conductivities from their precursor materials. These differences correlate with the concentrations of the phenolic compounds. Corresponding calibration curves have been established for a number of compounds. The sensors thus produced are capable to cover between 5 and 9 orders of magnitude in concentration – in the best case down to some picomoles. The sensor's detection sensitivity strongly depends on the specific compound. It is highest for caffeic acid and acid blue 74, followed by ABTS and ferulic acid.

Multithreaded hybrid feature tracking for markerless augmented reality.

Science.gov (United States)

Lee, Taehee; Höllerer, Tobias

2009-01-01

We describe a novel markerless camera tracking approach and user interaction methodology for augmented reality (AR) on unprepared tabletop environments. We propose a real-time system architecture that combines two types of feature tracking. Distinctive image features of the scene are detected and tracked frame-to-frame by computing optical flow. In order to achieve real-time performance, multiple operations are processed in a synchronized multi-threaded manner: capturing a video frame, tracking features using optical flow, detecting distinctive invariant features, and rendering an output frame. We also introduce user interaction methodology for establishing a global coordinate system and for placing virtual objects in the AR environment by tracking a user's outstretched hand and estimating a camera pose relative to it. We evaluate the speed and accuracy of our hybrid feature tracking approach, and demonstrate a proof-of-concept application for enabling AR in unprepared tabletop environments, using bare hands for interaction.

Improvements to ATLAS track reconstruction for Run II

Energy Technology Data Exchange (ETDEWEB)

Cairo, Valentina Maria Martina, E-mail: valentina.maria.cairo@cern.ch [University of Calabria, Arcavacata di Rende (Italy); CERN, Meyrin (Switzerland)

2016-07-11

Run II of the LHC will provide new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. A major change to the Inner Detector layout during the shutdown period has been the installation of the Insertable B-Layer, a fourth pixel layer located at a radius of 33 mm. This contribution discusses improvements to track reconstruction developed during the two year shutdown of the LHC. These include novel techniques developed to improve the performance in the dense cores of jets, optimisation for the expected conditions, and a big software campaign which lead to more than a factor of three decrease in the CPU time needed to process each recorded event.

Objective Identification of Environmental Patterns Related to Tropical Cyclone Track Forecast Errors

National Research Council Canada - National Science Library

Sanabia, Elizabeth R

2006-01-01

The increase in skill of numerical model guidance and the use of consensus forecast techniques have led to significant improvements in the accuracy of tropical cyclone track forecasts at ranges beyond 72 hours...

78 FR 46141 - Approval and Disapproval of Air Quality State Implementation Plans; Arizona; Regional Haze and...

Science.gov (United States)

2013-07-30

... for BART: ASARCO Hayden Smelter (Hayden Smelter); Freeport-McMoRan Inc. Miami Smelter (Miami Smelter..., we proposed to approve revisions to the sets of BART-eligible units at the Hayden and Miami Smelters... the Miami Smelter is exempt from a BART analysis for nitrogen oxides (NO X ), and that the Hayden...

Reallocating attention during multiple object tracking.

Science.gov (United States)

Ericson, Justin M; Christensen, James C

2012-07-01

Wolfe, Place, and Horowitz (Psychonomic Bulletin & Review 14:344-349, 2007) found that participants were relatively unaffected by selecting and deselecting targets while performing a multiple object tracking task, such that maintaining tracking was possible for longer durations than the few seconds typically studied. Though this result was generally consistent with other findings on tracking duration (Franconeri, Jonathon, & Scimeca Psychological Science 21:920-925, 2010), it was inconsistent with research involving cuing paradigms, specifically precues (Pylyshyn & Annan Spatial Vision 19:485-504, 2006). In the present research, we broke down the addition and removal of targets into separate conditions and incorporated a simple performance model to evaluate the costs associated with the selection and deselection of moving targets. Across three experiments, we demonstrated evidence against a cost being associated with any shift in attention, but rather that varying the type of cue used for target deselection produces no additional cost to performance and that hysteresis effects are not induced by a reduction in tracking load.

Methods and sensitivity for pass-by measurement of track decay rates

NARCIS (Netherlands)

Dittrich, M.G.

2012-01-01

Track decay rates are measured to characterize the track dynamics for railway noise type testing, but also for other purposes in relation to railway noise. They are often measured statically using hammer response functions on unloaded track, but can also be derived from rail vibrations on loaded

Image analysis used to count and measure etched tracks from ionizing radiation

Science.gov (United States)

Blanford, George E.; Schulz, Cindy K.

1995-01-01

We have developed techniques to use digitized scanning electron micrographs and computer image analysis programs to measure track densities in lunar soil grains and plastic dosimeters. Tracks in lunar samples are formed by highly ionizing solar energetic particles and cosmic rays during near surface exposure on the Moon. The track densities are related to the exposure conditions (depth and time). Distributions of the number of grains as a function of their track densities can reveal the modality of soil maturation. We worked on two samples identified for a consortium study of lunar weathering effects, 61221 and 67701. They were prepared by the lunar curator's staff as polished grain mounts that were etched in boiling 1 N NaOH for 6 h to reveal tracks. We determined that backscattered electron images taken at 10 percent contrast and approximately 50 percent brightness produced suitable high contrast images for analysis. We used the NIH Image program to cut out areas that were unsuitable for measurement such as edges, cracks, etc. We ascertained a gray-scale threshold of 25 to separate tracks from background. We used the computer to count everything that was two pixels or greater in size and to measure the area to obtain track densities. We found an excellent correlation with manual measurements for track densities below 1 x 10(exp 8) cm(exp -2). For track densities between 1 x 10(exp 8) cm(exp -2) to 1 x 10(exp 9) cm(exp -2) we found that a regression formula using the percentage area covered by tracks gave good agreement with manual measurements. We determined the track density distributions for 61221 and 67701. Sample 61221 is an immature sample, but not pristine. Sample 67701 is a submature sample that is very close to being fully mature. Because only 10 percent of the grains have track densities less than 10(exp 9) cm(exp -2), it is difficulty to determine whether the sample matured in situ or is a mixture of a mature and a submature soil. Although our analysis

Computer image analysis of etched tracks from ionizing radiation

Science.gov (United States)

Blanford, George E.

1994-01-01

I proposed to continue a cooperative research project with Dr. David S. McKay concerning image analysis of tracks. Last summer we showed that we could measure track densities using the Oxford Instruments eXL computer and software that is attached to an ISI scanning electron microscope (SEM) located in building 31 at JSC. To reduce the dependence on JSC equipment, we proposed to transfer the SEM images to UHCL for analysis. Last summer we developed techniques to use digitized scanning electron micrographs and computer image analysis programs to measure track densities in lunar soil grains. Tracks were formed by highly ionizing solar energetic particles and cosmic rays during near surface exposure on the Moon. The track densities are related to the exposure conditions (depth and time). Distributions of the number of grains as a function of their track densities can reveal the modality of soil maturation. As part of a consortium effort to better understand the maturation of lunar soil and its relation to its infrared reflectance properties, we worked on lunar samples 67701,205 and 61221,134. These samples were etched for a shorter time (6 hours) than last summer's sample and this difference has presented problems for establishing the correct analysis conditions. We used computer counting and measurement of area to obtain preliminary track densities and a track density distribution that we could interpret for sample 67701,205. This sample is a submature soil consisting of approximately 85 percent mature soil mixed with approximately 15 percent immature, but not pristine, soil.

Exploratory joint and separate tracking of geographically related time series

Science.gov (United States)

Balasingam, Balakumar; Willett, Peter; Levchuk, Georgiy; Freeman, Jared

2012-05-01

Target tracking techniques have usually been applied to physical systems via radar, sonar or imaging modalities. But the same techniques - filtering, association, classification, track management - can be applied to nontraditional data such as one might find in other fields such as economics, business and national defense. In this paper we explore a particular data set. The measurements are time series collected at various sites; but other than that little is known about it. We shall refer to as the data as representing the Megawatt hour (MWH) output of various power plants located in Afghanistan. We pose such questions as: 1. Which power plants seem to have a common model? 2. Do any power plants change their models with time? 3. Can power plant behavior be predicted, and if so, how far to the future? 4. Are some of the power plants stochastically linked? That is, do we observed a lack of power demand at one power plant as implying a surfeit of demand elsewhere? The observations seem well modeled as hidden Markov. This HMM modeling is compared to other approaches; and tests are continued to other (albeit self-generated) data sets with similar characteristics. Keywords: Time-series analysis, hidden Markov models, statistical similarity, clustering weighted

40 CFR 268.2 - Definitions applicable in this part.

Science.gov (United States)

2010-07-01

... radioactive lead solids; process residuals such as smelter slag and residues from the treatment of waste... Standards, except fluoride, selenium, sulfides, vanadium, and zinc, which can reasonably be expected to be...

Intelligent Sun Tracking for a CPV Power Plant

International Nuclear Information System (INIS)

Maqsood, Ishtiaq; Emziane, Mahieddine

2010-01-01

The output of a solar panel is strongly dependent on the amount of perpendicular light flux falling on its surface, and a tracking system tries to parallel the vector area of the solar panel surface to the incident solar flux. We present a tracking technique based on a two-axis sun sensor which can be used to increase the power output from a number of CPV arrays connected together in a solar power plant. The outdoor testing procedure of the developed two-axis sun sensor is discussed. The detail of the algorithm used together with the related sun tracking equipment is also presented and discussed for the new two axes sun tracking system.

Neutron-induced complex reaction analysis with 3D nuclear track simulation

International Nuclear Information System (INIS)

Sajo-Bohus, L.; Palfalvi, J.K.; Akatov, Yu.; Arevalo, O.; Greaves, E.D.; Nemeth, P.; Palacios, D.; Szabo, J.; Eoerdoegh, I.

2005-01-01

Complex (multiple) etched tracks are analysed through digitised images and 3D simulation by a purpose-built algorithm. From a binary track image an unfolding procedure is followed to generate a 3D track model, from which several track parameters are estimated. The method presented here allows the deposited energy, that originated from particle fragmentation or carbon spallation by means of induced tracks in commercially available PADC detectors, to be estimated. Results of evaluated nuclear tracks related to 12 C (n,3αn ' ) reaction are presented here. The detectors were exposed on the ISS in 2001

Exploring differences in speech processing among elderly hearing-impaired listeners with or without hearing aid experience: Eye-tracking and fMRI measurements

DEFF Research Database (Denmark)

Habicht, Julia; Behler, Oliver; Kollmeier, Birger

2018-01-01

on the cognitive processes underlying speech comprehension. Eye-tracking and functional magnetic resonance imaging (fMRI) measurements were carried out with acoustic sentence-in-noise (SIN) stimuli complemented by pairs of pictures that either correctly (target) or incorrectly (competitor) depicted the sentence...... meanings. For the eye-tracking measurements, the time taken by the participants to start fixating the target picture (the ‘processing time’) was measured. For the fMRI measurements, brain activation inferred from blood oxygenation level dependent (BOLD) responses following sentence comprehension...... frontal areas for SIN relative to noise-only stimuli in the eHA group compared to the iHA group. Together, these results imply that HA experience leads to faster speech-in-noise processing, possibly related to less recruitment of brain regions outside the core sentence-comprehension network. Follow...

The RASNIK real-time relative alignment monitor for the CDF inner tracking detectors

International Nuclear Information System (INIS)

Goldstein, David; Saltzberg, David

2003-01-01

We describe the design and operation of the RASNIK optical relative alignment system designed for and installed on the CDF inner tracking detectors. The system provides low-cost minute-by-minute alignment monitoring with submicron precision. To reduce ambiguities, we modified the original three-element RASNIK design to a two-element one. Since the RASNIKs are located within 10-40 cm of the beam line, the systems were built from low-mass and radiation-hard components and are operated in a mode which reduces damage from radiation. We describe the data-acquisition system, which has been running without interruption since before the CDF detector was rolled into its collision hall in March 2001. We evaluate what has been learned about sources of detector motion from almost 2 years of RASNIK data and discuss possible improvements to the system

Ion track etching revisited: II. Electronic properties of aged tracks in polymers

Czech Academy of Sciences Publication Activity Database

Fink, Dietmar; Hernandez, G. M.; Cruz, S. A.; Garcia-Arellano, H.; Vacík, Jiří; Hnatowicz, Vladimír; Kiv, A.; Alfonta, L.

2018-01-01

Roč. 173, 1-2 (2018), s. 148-164 ISSN 1042-0150 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:61389005 Keywords : polymers * ion tracks * etching * conductometry * rectification * phase shift Subject RIV: JF - Nuclear Energetics OBOR OECD: Nuclear related engineering Impact factor: 0.443, year: 2016

Readability of Spine-Related Patient Education Materials From Leading Orthopedic Academic Centers.

Science.gov (United States)

Ryu, Justine H; Yi, Paul H

2016-05-01

Cross-sectional analysis of online spine-related patient education materials from leading academic centers. To assess the readability levels of spine surgery-related patient education materials available on the websites of academic orthopedic surgery departments. The Internet is becoming an increasingly popular resource for patient education. Yet many previous studies have found that Internet-based orthopedic-related patient education materials from subspecialty societies are written at a level too difficult for the average American; however, no prior study has assessed the readability of spine surgery-related patient educational materials from leading academic centers. All spine surgery-related articles from the online patient education libraries of the top five US News & World Report-ranked orthopedic institutions were assessed for readability using the Flesch-Kincaid (FK) readability test. Mean readability levels of articles amongst the five academic institutions and articles were compared. We also determined the number of articles with readability levels at or below the recommended sixth- or eight-grade levels. Intraobserver and interobserver reliability of readability assessment were assessed. A total of 122 articles were reviewed. The mean overall FK grade level was 11.4; the difference in mean FK grade level between each department varied significantly (range, 9.3-13.4; P Online patient education materials related to spine from academic orthopedic centers are written at a level too high for the average patient, consistent with spine surgery-related patient education materials provided by the American Academy of Orthopaedic Surgeons and spine subspecialty societies. This study highlights the potential difficulties patients might have in reading and comprehending the information in publicly available education materials related to spine. N/A.

Evidence-based surgical care and the evolution of fast-track surgery

DEFF Research Database (Denmark)

Kehlet, H.; Wilmore, D.W.

2008-01-01

, randomized studies, and meta-analyses, the concept of the "fast-track methodology" has uniformly provided a major enhancement in recovery leading to decreased hospital stay and with an apparent reduction in medical morbidity but unaltered "surgery-specific" morbidity in a variety of procedures. However......BACKGROUND: Optimization of postoperative outcome requires the application of evidence-based principles of care carefully integrated into a multimodal rehabilitation program. OBJECTIVE: To assess, synthesize, and discuss implementation of "fast-track" recovery programs. DATA SOURCES: Medline MBASE...... (January 1966-May 2007) and the Cochrane library (January 1966-May 2007) were searched using the following keywords: fast-track, enhanced recovery, accelerated rehabilitation, and multimodal and perioperative care. In addition, the synthesis on the many specific interventions and organizational...

Atmospheric deposition study in the area of Kardzhali lead-zinc plant based on moss analysis

International Nuclear Information System (INIS)

Hristozova, G.; Marinova, S.; Strelkova, L.P.; Goryajnova, Z.; Frontas'eva, M.V.; Stafilov, T.

2015-01-01

For the first time the moss biomonitoring technique was used to assess the environmental situation in the area affected by the lead-zinc plant as one of the most hazardous enterprises in Bulgaria. 77 Hypnum cupressiforme moss samples were collected in the Kardzhali municipality in the summer and autumn of 2011. The concentrations of a total of 47 elements were determined by means of instrumental epithermal neutron activation analysis (ENAA), atomic absorption spectrometry (AAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Multivariate statistics was applied to characterize the sources of elements detected in the samples. Four groups of elements were found. In comparison to the data averaged for the area outside of the town, the atmospheric deposition loads for the elements of industrial origin in Kardzhali, where the smelter chimney is located, were found to be much higher. Median levels of the measured concentrations of the most toxic metals (Pb, Zn, Cd, As, Cu, In, Sb) were extremely high in this hot spot when compared to the median Bulgarian cross-country data from the 2010-2011 European moss survey. GIS technology was used to produce element distribution maps illustrating deposition patterns of element pollutants in the study area. The results obtained contribute to the Bulgarian environmental research used to study and control the manufacturing processes of the lead-zinc plant in the town of Kardzhali.

A Pilot Study of Children’s Blood Lead Levels in Mount Isa, Queensland

Directory of Open Access Journals (Sweden)

Donna Green

2017-12-01

Full Text Available Mount Isa, Queensland, is one of three Australian cities with significant lead emissions due to nonferrous mining and smelting. Unlike the two other cities with lead mines or smelters, Mount Isa currently has no system of annual, systematic, community-wide blood lead level testing; and testing rates among Indigenous children are low. In previous screenings, this group of children has been shown to have higher average blood lead levels than non-Indigenous children. The first aim of this study was to assess whether parents and children would participate in less invasive, rapid point-of-care capillary testing. The second aim was to measure blood lead levels among a range of children that roughly reflected the percentage of the Indigenous/non-Indigenous population. This pilot study is based on a convenience sample of children between the ages of 12 and 83 months who were recruited to participate by staff at a Children and Family Centre. Over three half-days, 30 children were tested using capillary blood samples and the LeadCare II Point-of-Care testing system. Rapid point-of-care capillary testing was well tolerated by the children. Of 30 children tested, 40% (n = 12 had blood lead levels ≥5 µg/dL and 10% had levels ≥10 µg/dL. The highest blood lead level measured was 17.3 µg/dL. The percentage of children with blood lead levels ≥5 µg/dL was higher among Indigenous children compared to non-Indigenous (64.2% compared to 18.8% as was the geometric mean level (6.5 (95% CI, 4.7, 9.2 versus 2.4 (95% CI, 1.8, 3.1, a statistically significant difference. Though based on a small convenience sample, this study identified 12 children (40% of the sample with blood lead levels ≥5 µg/dL. Due to historical and ongoing heavy metal emissions from mining and smelting in Mount Isa, we recommend a multi-component program of universal blood lead level testing, culturally appropriate follow-up and intervention for children who are identified with blood lead

Mineralogy and environmental stability of slags from the Tsumeb smelter, Namibia

International Nuclear Information System (INIS)

Ettler, Vojtech; Johan, Zdenek; Kribek, Bohdan; Sebek, Ondrej; Mihaljevic, Martin

2009-01-01

Three types of smelting slags originating from historically different smelting technologies in the Tsumeb area (Namibia) were studied: (i) slags from processing of carbonate/oxide ore in a Cu-Pb smelter (1907-1948), (ii) slags from Cu and Pb smelting of sulphide ores (1963-1970) and (iii) granulated Cu smelting slags (1980-2000). Bulk chemical analyses of slags were combined with detailed mineralogical investigation using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM/EDS) and electron microprobe (EPMA). The slags are significantly enriched in metals and metalloids: Pb (0.97-18.4 wt.%), Cu (0.49-12.2 wt.%), Zn (2.82-12.09 wt.%), Cd (12-6940 mg/kg), As (930-75,870 mg/kg) and Sb (67-2175 mg/kg). Slags from the oldest technology are composed of primary Ca- and Pb-bearing feldspars, spinels, complex Cu-Fe and Cu-Cr oxides, delafossite-mcconnellite phases and Ca-Pb arsenates. The presence of arsenates indicates that these slags underwent long-term alteration. More recent slags are composed of high-temperature phases: Ca-Fe alumosilicates (olivine, melilite), Pb- and Zn-rich glass, spinel oxides and small sulphide/metallic inclusions embedded in glass. XRD and SEM/EDS were used to study secondary alteration products developed on the surface of slags exposed for decades to weathering on the dumps. Highly soluble complex Cu-Pb-(Ca) arsenates (bayldonite, lammerite, olivenite, lavendulan) associated with litharge and hydrocerussite were detected. To determine the mineralogical and geochemical parameters governing the release of inorganic contaminants from slags, two standardized short-term batch leaching tests (European norm EN 12457 and USEPA TCLP), coupled with speciation-solubility modelling using PHREEQC-2 were performed. Arsenic in the leachate exceeded the EU regulatory limit for hazardous waste materials (2.5 mg/L). The toxicity limits defined by USEPA for the TCLP test were exceeded for Cd, Pb and As. The PHREEQC-2 calculation predicted that

Advanced Alignment of the ATLAS Tracking System

CERN Document Server

Pedraza Lopez, S; The ATLAS collaboration

2012-01-01

In order to reconstruct trajectories of charged particles, ATLAS is equipped with a tracking system built using different technologies embedded in a 2T solenoidal magnetic field. ATLAS physics goals require high resolution, unbiased measurement of all charged particle kinematic parameters in order to assure accurate invariant mass reconstruction and interaction and decay vertex finding. These critically depend on the systematic effects related to the alignment of the tracking system. In order to eliminate malicious systematic deformations, various advanced tools and techniques have been put in place. These include information from known mass resonances, energy of electrons and positrons measured by the electromagnetic calorimeters, etc. Despite being stable under normal running conditions, ATLAS tracking system responses to sudden environ-mental changes (temperature, magnetic field) by small collective deformations. These have to be identified and corrected in order to assure uniform, highest quality tracking...

An auxiliary frequency tracking system for general purpose lock-in amplifiers

Science.gov (United States)

Xie, Kai; Chen, Liuhao; Huang, Anfeng; Zhao, Kai; Zhang, Hanlu

2018-04-01

Lock-in amplifiers (LIAs) are designed to measure weak signals submerged by noise. This is achieved with a signal modulator to avoid low-frequency noise and a narrow-band filter to suppress out-of-band noise. In asynchronous measurement, even a slight frequency deviation between the modulator and the reference may lead to measurement error because the filter’s passband is not flat. Because many commercial LIAs are unable to track frequency deviations, in this paper we propose an auxiliary frequency tracking system. We analyze the measurement error caused by the frequency deviation and propose both a tracking method and an auto-tracking system. This approach requires only three basic parameters, which can be obtained from any general purpose LIA via its communications interface, to calculate the frequency deviation from the phase difference. The proposed auxiliary tracking system is designed as a peripheral connected to the LIA’s serial port, removing the need for an additional power supply. The test results verified the effectiveness of the proposed system; the modified commercial LIA (model SR-850) was able to track the frequency deviation and continuous drift. For step frequency deviations, a steady tracking error of less than 0.001% was achieved within three adjustments, and the worst tracking accuracy was still better than 0.1% for a continuous frequency drift. The tracking system can be used to expand the application scope of commercial LIAs, especially for remote measurements in which the modulation clock and the local reference are separated.

Solar tracking system

Science.gov (United States)

Okandan, Murat; Nielson, Gregory N.

2016-07-12

Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

Qualitative Video Analysis of Track-Cycling Team Pursuit in World-Class Athletes.

Science.gov (United States)

Sigrist, Samuel; Maier, Thomas; Faiss, Raphael

2017-11-01

Track-cycling team pursuit (TP) is a highly technical effort involving 4 athletes completing 4 km from a standing start, often in less than 240 s. Transitions between athletes leading the team are obviously of utmost importance. To perform qualitative video analyses of transitions of world-class athletes in TP competitions. Videos captured at 100 Hz were recorded for 77 races (including 96 different athletes) in 5 international track-cycling competitions (eg, UCI World Cups and World Championships) and analyzed for the 12 best teams in the UCI Track Cycling TP Olympic ranking. During TP, 1013 transitions were evaluated individually to extract quantitative (eg, average lead time, transition number, length, duration, height in the curve) and qualitative (quality of transition start, quality of return at the back of the team, distance between third and returning rider score) variables. Determination of correlation coefficients between extracted variables and end time allowed assessment of relationships between variables and relevance of the video analyses. Overall quality of transitions and end time were significantly correlated (r = .35, P = .002). Similarly, transition distance (r = .26, P = .02) and duration (r = .35, P = .002) were positively correlated with end time. Conversely, no relationship was observed between transition number, average lead time, or height reached in the curve and end time. Video analysis of TP races highlights the importance of quality transitions between riders, with preferably swift and short relays rather than longer lead times for faster race times.

Management of three-dimensional intrafraction motion through real-time DMLC tracking

International Nuclear Information System (INIS)

Sawant, Amit; Venkat, Raghu; Srivastava, Vikram; Carlson, David; Povzner, Sergey; Cattell, Herb; Keall, Paul

2008-01-01

Tumor tracking using a dynamic multileaf collimator (DMLC) represents a promising approach for intrafraction motion management in thoracic and abdominal cancer radiotherapy. In this work, we develop, empirically demonstrate, and characterize a novel 3D tracking algorithm for real-time, conformal, intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT)-based radiation delivery to targets moving in three dimensions. The algorithm obtains real-time information of target location from an independent position monitoring system and dynamically calculates MLC leaf positions to account for changes in target position. Initial studies were performed to evaluate the geometric accuracy of DMLC tracking of 3D target motion. In addition, dosimetric studies were performed on a clinical linac to evaluate the impact of real-time DMLC tracking for conformal, step-and-shoot (S-IMRT), dynamic (D-IMRT), and VMAT deliveries to a moving target. The efficiency of conformal and IMRT delivery in the presence of tracking was determined. Results show that submillimeter geometric accuracy in all three dimensions is achievable with DMLC tracking. Significant dosimetric improvements were observed in the presence of tracking for conformal and IMRT deliveries to moving targets. A gamma index evaluation with a 3%-3 mm criterion showed that deliveries without DMLC tracking exhibit between 1.7 (S-IMRT) and 4.8 (D-IMRT) times more dose points that fail the evaluation compared to corresponding deliveries with tracking. The efficiency of IMRT delivery, as measured in the lab, was observed to be significantly lower in case of tracking target motion perpendicular to MLC leaf travel compared to motion parallel to leaf travel. Nevertheless, these early results indicate that accurate, real-time DMLC tracking of 3D tumor motion is feasible and can potentially result in significant geometric and dosimetric advantages leading to more effective management of intrafraction motion

Analysis of the hematological and biochemical parameters related to lead intoxication.

Science.gov (United States)

Yılmaz, Hınç; Keten, Alper; Karacaoğlu, Emre; Tutkun, Engin; Akçan, Ramazan

2012-11-01

In parallel with industrial advancements, number of the occupational diseases secondary to chemical exposure is increasing. The chemical agents in the work places affect various organ and tissue systems, leading to chronic diseases. In this study, the cases diagnosed with occupational disease due to exposure to lead were studied and importance of the environmental forensic sciences on this issue was emphasized. A hundred and ninety patients diagnosed with occupational disease related to lead intoxication in Ankara Occupational Diseases Hospital between 01/01/2009 and 31/12/2009 were included in the study. Twenty cases were used as the controls. Sociodemographic characteristics, serum chemical parameters and hematological parameters of the patients were retrospectively assessed. Mean age of the cases included in the study was 35.3±8.69. Hemoglobin (Hb) (p=0.018) and Mean corpuscular volume (MCV) (plead exposure than in the controls. Gamma glutamyl transferase (GGT) was significantly lower in the patients with lead exposure than in the controls (p=0.002), whereas alkaline phosphatase (ALP) was found higher (plead exposure than in the control group (p=0.01), while Thyrotrophin-stimulating hormone (TSH) levels were lower (plead (Pb) was correlated positively with ALP values and negatively with Hb, MCV and TSH. Considering its effects on the biochemical and hematological parameters, a detailed investigation should be carried out in the cases with lead exposure, which occupies an important place among the occupational diseases. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

The use of a break-even analysis: financial analysis of a fast-track program.

Science.gov (United States)

Saywell, R M; Cordell, W H; Nyhuis, A W; Giles, B K; Culler, S D; Woods, J R; Chu, D K; McKinzie, J P; Rodman, G H

1995-08-01

To calculate the financial break-even point and illustrate how changes in third-party reimbursement and eligibility could affect a program's fiscal standing. Demographic, clinical, and financial data were collected retrospectively for 446 patients treated in a fast-track program during June 1993. The fast-track program is located within the confines of the emergency medicine and trauma center at a 1,050-bed tertiary care Midwestern teaching hospital and provides urgent treatment to minimally ill patients. A financial break-even analysis was performed to determine the point where the program generated enough revenue to cover its total variable and fixed costs, both direct and indirect. Given the relatively low average collection rate (62%) and high percentage of uninsured patients (31%), the analysis showed that the program's revenues covered its direct costs but not all of the indirect costs. Examining collection rates or payer class mix without examining both costs and revenues may lead to an erroneous conclusion about a program's fiscal viability. Sensitivity analysis also shows that relatively small changes in third-party coverage or eligibility (income) requirements can have a large impact on the program's financial solvency and break-even volumes.

Science and technology with nuclear tracks in solids

CERN Document Server

Buford-Price, P

2005-01-01

Fission track dating has greatly expanded its usefulness to geology over the last 40 years. It is central to thermochronology—the use of shortened fission tracks to decipher the thermal history, movement, and provenance of rocks. When combined with other indicators, such as zircon color and (U–Th)/He, a range of temperatures from C to C can be studied. Combining fission track analysis with cosmogenic nuclide decay rates, one can study landscape development and denudation of passive margins. Technological applications have expanded from biological filters, radon mapping, and dosimetry to the use of ion track microtechnology in microlithography, micromachining by ion track etching, microscopic field emission tips, magnetic nanowires as magnetoresistive sensors, microfluidic devices, physiology of ion channels in single cells, and so on. In nuclear and particle physics, relatively insensitive glass detectors have been almost single-handedly responsible for our knowledge of cluster radioactivity, and plastic ...

In vivo x-ray fluorescence of bone lead in the study of human lead metabolism: Serum lead, whole blood lead, bone lead, and cumulative exposure

International Nuclear Information System (INIS)

Cake, K.M.; Chettle, D.R.; Webber, C.E.; Gordon, C.L.

1995-01-01

Traditionally, clinical studies of lead's effect on health have relied on blood lead levels to indicate lead exposure. However, this is unsatisfactory because blood lead levels have a half-life of approximately 5 weeks, and thus reflect recent exposure. Over 90% of the lead body burden is in bone, and it is thought to have a long residence time, thus implying that measurements of bone lead reflect cumulative exposure. So, measurements of bone lead are useful in understanding the long-term health effects of lead. Ahlgren reported the first noninvasive measurements of bone lead in humans, where γ-rays from 57 Co were used to excite the K series x-rays of lead. The lead detection system at McMaster University uses a 109 Cd source which is positioned at the center of the detector face (HPGe) and a near backscatter (∼160 degrees) geometry. This arrangement allows great flexibility, since one can sample lead in a range of different bone sites due to a robust normalization technique which eliminates the need to correct for bone geometry, thickness of overlying tissue, and other related factors. The effective radiation dose to an adult during an x-ray fluorescence bone lead measurement is extremely low, being 35 nSv. This paper addresses the issue of how bone, whole blood, and serum lead concentrations can be related in order to understand a person's lead exposure history