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Sample records for case study polycyclic

  1. Differential scanning calorimetry method for purity determination: A case study on polycyclic aromatic hydrocarbons and chloramphenicol

    International Nuclear Information System (INIS)

    Kestens, V.; Zeleny, R.; Auclair, G.; Held, A.; Roebben, G.; Linsinger, T.P.J.

    2011-01-01

    Highlights: → Purity assessment of polycyclic aromatic hydrocarbons and chloramphenicol by DSC. → DSC results compared with traditional purity methods. → Different methods give different results, multiple method approach recommended. → DSC sensitive to impurities that have similar structures as main component. - Abstract: In this study the validity and suitability of differential scanning calorimetry (DSC) to determine the purity of selected polycyclic aromatic hydrocarbons and chloramphenicol has been investigated. The study materials were two candidate certified reference materials (CRMs), 6-methylchrysene and benzo[a]pyrene, and two different batches of commercially available highly pure chloramphenicol. The DSC results were compared with those obtained by other methods, namely gas and liquid chromatography with mass spectrometric detection, liquid chromatography with diode array detection, and quantitative nuclear magnetic resonance. The purity results obtained by these different analytical methods confirm the well-known challenges of comparing results of different method-defined measurands. In comparison with other methods, DSC has a much narrower working range. This limits the applicability of DSC as purity determination method, for instance during the assignment of the purity value of a CRM. Nevertheless, this study showed that DSC can be a powerful technique to detect impurities that are structurally very similar to the main purity component. From this point of view, and because of its good repeatability, DSC can be considered as a valuable technique to investigate the homogeneity and stability of candidate purity CRMs.

  2. Risk of human exposure to polycyclic aromatic hydrocarbons: A case study in Beijing, China

    International Nuclear Information System (INIS)

    Yu, Yanxin; Li, Qi; Wang, Hui; Wang, Bin; Wang, Xilong; Ren, Aiguo; Tao, Shu

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAHs) can cause adverse effects on human health. The relative contributions of their two major intake routes (diet and inhalation) to population PAH exposure are still unclear. We modeled the contributions of diet and inhalation to the overall PAH exposure of the population of Beijing in China, and assessed their human incremental lifetime cancer risks (ILCR) using a Mont Carlo simulation approach. The results showed that diet accounted for about 85% of low-molecular-weight PAH (L-PAH) exposure, while inhalation accounted for approximately 57% of high-molecular-weight PAH (H-PAH) exposure of the Beijing population. Meat and cereals were the main contributors to dietary PAH exposure. Both gaseous- and particulate-phase PAHs contributed to L-PAH exposure through inhalation, whereas exposure to H-PAHs was mostly from the particulate-phase. To reduce the cancer incidence of the Beijing population, more attention should be given to inhaled particulate-phase PAHs with considerable carcinogenic potential. - Highlights: • We modeled the contributions of diet and inhalation to population PAH exposure. • Diet contributed 85% of population exposure to low molecular-weight PAHs. • Inhalation contributed 57% of population exposure to high molecular-weight PAHs. • The PAH exposure level with body-weight adjustment decreased with age increasing. • The population cancer risk of PAH exposure is lower than the serious risk level. - The exposure of the Beijing population to carcinogenic polycyclic aromatic hydrocarbons was mainly from inhaled particulate matter

  3. Polycyclic aromatic acids are primary metabolites of alkyl-PAHs - a case study with Nereis diversicolor

    DEFF Research Database (Denmark)

    Malmquist, Linus Mattias Valdemar; Selck, Henriette; Jørgensen, Kåre Bredeli

    2015-01-01

    Although concentrations of alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) in oil-contaminated sediments are higher than those of unsubstituted PAHs, only little attention has been given to metabolism and ecotoxicity of alkyl-PAHs. In this study we demonstrated that metabolism of alkyl-PA...... that carboxylic acid metabolites of alkyl-PAHs have the potential of constituting a new class of contaminants in marine waters that needs attention in relation to ecological risk assessments.......Although concentrations of alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) in oil-contaminated sediments are higher than those of unsubstituted PAHs, only little attention has been given to metabolism and ecotoxicity of alkyl-PAHs. In this study we demonstrated that metabolism of alkyl...

  4. Regional modelling of polycyclic aromatic hydrocarbons: WRF-Chem-PAH model development and East Asia case studies

    Science.gov (United States)

    Mu, Qing; Lammel, Gerhard; Gencarelli, Christian N.; Hedgecock, Ian M.; Chen, Ying; Přibylová, Petra; Teich, Monique; Zhang, Yuxuan; Zheng, Guangjie; van Pinxteren, Dominik; Zhang, Qiang; Herrmann, Hartmut; Shiraiwa, Manabu; Spichtinger, Peter; Su, Hang; Pöschl, Ulrich; Cheng, Yafang

    2017-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are hazardous pollutants, with increasing emissions in pace with economic development in East Asia, but their distribution and fate in the atmosphere are not yet well understood. We extended the regional atmospheric chemistry model WRF-Chem (Weather Research Forecast model with Chemistry module) to comprehensively study the atmospheric distribution and the fate of low-concentration, slowly degrading semivolatile compounds. The WRF-Chem-PAH model reflects the state-of-the-art understanding of current PAHs studies with several new or updated features. It was applied for PAHs covering a wide range of volatility and hydrophobicity, i.e. phenanthrene, chrysene and benzo[a]pyrene, in East Asia. Temporally highly resolved PAH concentrations and particulate mass fractions were evaluated against observations. The WRF-Chem-PAH model is able to reasonably well simulate the concentration levels and particulate mass fractions of PAHs near the sources and at a remote outflow region of East Asia, in high spatial and temporal resolutions. Sensitivity study shows that the heterogeneous reaction with ozone and the homogeneous reaction with the nitrate radical significantly influence the fate and distributions of PAHs. The methods to implement new species and to correct the transport problems can be applied to other newly implemented species in WRF-Chem.

  5. Assessment of the toxicity of a substance under Canadian environmental protection act, a case study. Polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Nadon, B.; Germain, A.; Coillie, R. van [Environment Canada, Montreal (Canada)

    1995-12-31

    The Canadian Environmental Protection Act (CEPA) proclaimed in 1988 requires the Canadian Ministers of the Environment and of National Health and Welfare to assess the toxicity of different substances. A Priority Substances List containing 44 substances was developed and their assessments had to determine if they were `toxic`, according to the CEPA definition. This definition states that `a substance is toxic if it is entering or may enter the environment in a quantity or concentration or under conditions (a) having or that may have an immediate or long-term harmful effect on the environment, (b) constituting or that may constitute a danger to the environment on which human life depends; or (c) constituting or that may constitute a danger in Canada to human life of health.` This presentation use the assessment of the polycyclic aromatic hydrocarbons (PAHs) as an example of this procedure. (author)

  6. Assessment of the toxicity of a substance under Canadian environmental protection act, a case study. Polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Nadon, B; Germain, A; Coillie, R van [Environment Canada, Montreal (Canada)

    1996-12-31

    The Canadian Environmental Protection Act (CEPA) proclaimed in 1988 requires the Canadian Ministers of the Environment and of National Health and Welfare to assess the toxicity of different substances. A Priority Substances List containing 44 substances was developed and their assessments had to determine if they were `toxic`, according to the CEPA definition. This definition states that `a substance is toxic if it is entering or may enter the environment in a quantity or concentration or under conditions (a) having or that may have an immediate or long-term harmful effect on the environment, (b) constituting or that may constitute a danger to the environment on which human life depends; or (c) constituting or that may constitute a danger in Canada to human life of health.` This presentation use the assessment of the polycyclic aromatic hydrocarbons (PAHs) as an example of this procedure. (author)

  7. Photoacoustic spectroscopic studies of polycyclic aromatic hydrocarbons

    Science.gov (United States)

    Zaidi, Zahid H.; Kumar, Pardeep; Garg, R. K.

    1999-02-01

    Because of their involvement in environmental pollutants, in carcinogenic activity, plastics, pharmaceuticals, synthesis of some laser dyes and presence in interstellar space etc., Polycyclic aromatic hydrocarbons (PAHs) are important. As their structure and properties can be varied systematically, they form a beautiful class of molecules for experimental and quantum chemical investigations. These molecules are being studied for last several years by using conventional spectroscopy. In recent years, Photoacoustic (PA) spectroscopy has emerged as a new non-destructive technique with unique capability and sensitivity. The PA effect is the process of generation of acoustic waves in a sample resulting from the absorption of photons. This technique not only reveals non- radiative transitions but also provides information about forbidden singlet-triplet transitions which are not observed normally by the conventional spectroscopy. The present paper deals with the spectroscopic studies of some PAH molecules by PA spectroscopy in the region 250 - 400 nm. The CNDO/S-CI method is used to calculate the electronic transitions with the optimized geometries. A good agreement is found between the experimental and calculated results.

  8. Patterns of traffic polycyclic aromatic hydrocarbon pollution in mountain areas can be revealed by lichen biomonitoring: a case study in the Dolomites (Eastern Italian Alps).

    Science.gov (United States)

    Nascimbene, Juri; Tretiach, Mauro; Corana, Federica; Lo Schiavo, Fiorella; Kodnik, Danijela; Dainese, Matteo; Mannucci, Barbara

    2014-03-15

    In mountain areas of touristic interest the evaluation of the impact of human activities is crucial for ensuring long-term conservation of ecosystem biodiversity, functions and services. This study aimed at verifying the biological impact of polycyclic aromatic hydrocarbon (PAH) emissions due to traffic along the roads leading to seven passes of the Dolomites (SE Alps), which were recently declared a UNESCO World Heritage Site. Thalli of the epiphytic lichen Pseudevernia furfuracea, collected at increasing distances from the roads, were used as biomonitors. Our study revealed a gradient of decreasing PAH pollution within 300 m from the roads. Differences among passes were evident mainly for samples collected nearest to the roads, but PAH concentrations at 300 m were almost always higher than those of undisturbed reference sites, indicating that traffic PAH pollution may impact natural ecosystems and lichen diversity at relatively long distances from the emission source. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Distribution of Gas Phase Polycyclic Aromatic Hydrocarbons (PAHs in Selected Indoor and Outdoor Air Samples of Malaysia: a Case Study in Serdang, Selangor and Bachang, Malacca

    Directory of Open Access Journals (Sweden)

    Haris Hafizal Abd Hamid

    2017-07-01

    Full Text Available Distribution of 10 polycyclic aromatic hydrocarbons (PAHs in the gas phase of air from selected indoor and outdoor areas of Selangor and Malacca, Malaysia has been investigated. A locally designed Semi Permeable Membrane Device (SPMD was applied for passive air sampling for 37 days at selected locations. Cleanup was carried out with Gas Purge - Micro Syringe Extraction (GP-MSE and the final analysis was using Gas Chromatography-Mass Spectrometry (GC-MS. In this study, 6 indoor and 12 outdoor locations were selected for air sampling. A total of 10 compounds of PAHs (Ʃ10PAHs were determined in the range of 0.218 ng/m3 - 1.692 ng/m3 and 0.378 ng/m3 - 1.492 ng/m3 in outdoor and indoor samples respectively. In the outdoor samples, locations such as near a petrol station and heavy traffic showed the maximum levels of Ʃ10PAHs, while rooftop samples showed the lowest Ʃ10PAHs. The distribution of gas phase Ʃ10PAHs was influenced by vehicular emission. Low molecular weight (LMW compounds (2-3 rings were dominant in all samples (>70% indicating that SPMD has successfully sampled the gas phase of the air.

  10. A study of the microbiology and polycyclic aromatic hydrocarbons ...

    African Journals Online (AJOL)

    A study was carried out on the drill cuttings from three different oil and gas wells located at Ologbo Community at Edo State with respect to their microbiology and polycyclic aromatic hydrocarbons (PAHs) compositional profile and sources. Isolation and enumeration of heterotrophic bacteria and fungi was carried out using ...

  11. Dietary and inhalation exposure to polycyclic aromatic hydrocarbons and urinary excretion of monohydroxy metabolites – A controlled case study in Beijing, China

    International Nuclear Information System (INIS)

    Zhang, Yanyan; Ding, Junnan; Shen, Guofeng; Zhong, Junjun; Wang, Chen; Wei, Siye; Chen, Chaoqi; Chen, Yuanchen; Lu, Yan; Shen, Huizhong; Li, Wei; Huang, Ye; Chen, Han; Su, Shu; Lin, Nan; Wang, Xilong; Liu, Wenxin; Tao, Shu

    2014-01-01

    Daily dietary and inhalation exposures to 16 parent polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 13 monohydroxy metabolites (OHPAHs) were monitored for 12 non-smoking university students in Beijing, China, during a controlled feeding experiment. The relationship between the urinary excretion of OHPAHs and the uptake of PAHs was investigated. The results suggest severe exposure of the subjects to PAHs via both dietary and inhalation pathways. Large increase of most urinary OHPAHs occurred after the ingestion of lamb kabob. Higher concentrations of OHPAHs were observed for female subjects, with the intakes of parent PAHs lower than those by males, likely due to the gender differences in metabolism. It appears that besides 1-PYR, metabolites of PHE could also be used as biomarkers to indicate the short-term dietary exposure to PAHs and urinary 3-BaA may serve as the biomarker for inhalation intake of high molecular weight PAHs. Highlights: • The dependence of urinary OHPAHs on PAH intake was explored. • Consumption of lamb kabob resulted in large increase of most urinary OHPAHs. • Gender differences in PAH metabolism was observed. • Urinary metabolites of PHE and PYR can be used as biomarkers for dietary PAH intake. • Urinary 3-BaA may serve as the indicator for the inhalation exposure to BaP eq . -- Severe exposure to PAHs via dietary and inhalation pathways indicated by the intake of parent PAHs as well as the urinary excretion of OHPAHs, was observed for students in Beijing

  12. Exposure to polycyclic aromatic hydrocarbons (PAHs) and bladder cancer: evaluation from a gene-environment perspective in a hospital-based case-control study in the Canary Islands (Spain)

    Science.gov (United States)

    Boada, Luis D; Henríquez-Hernández, Luis A; Navarro, Patricio; Zumbado, Manuel; Almeida-González, Maira; Camacho, María; Álvarez-León, Eva E; Valencia-Santana, Jorge A; Luzardo, Octavio P

    2015-01-01

    Background: Exposure to polycyclic aromatic hydrocarbons (PAHs) has been linked to bladder cancer. Objective: To evaluate the role of PAHs in bladder cancer, PAHs serum levels were measured in patients and controls from a case-control study. Methods: A total of 140 bladder cancer patients and 206 healthy controls were included in the study. Sixteen PAHs were analyzed from the serum of subjects by gas chromatography–mass spectrometry. Results: Serum PAHs did not appear to be related to bladder cancer risk, although the profile of contamination by PAHs was different between patients and controls: pyrene (Pyr) was solely detected in controls and chrysene (Chry) was exclusively detected in the cases. Phenanthrene (Phe) serum levels were inversely associated with bladder cancer (OR = 0·79, 95%CI = 0·64–0·99, P = 0·030), although this effect disappeared when the allelic distribution of glutathione-S-transferase polymorphisms of the population was introduced into the model (multinomial logistic regression test, P = 0·933). Smoking (OR = 3·62, 95%CI = 1·93–6·79, P<0·0001) and coffee consumption (OR = 1·73, 95%CI = 1·04–2·86, P = 0·033) were relevant risk factors for bladder cancer. Conclusions: Specific PAH mixtures may play a relevant role in bladder cancer, although such effect seems to be highly modulated by polymorphisms in genes encoding xenobiotic-metabolizing enzymes. PMID:25291984

  13. Dissociation of polycyclic aromatic hydrocarbons: molecular dynamics studies

    Science.gov (United States)

    Simon, A.; Rapacioli, M.; Rouaut, G.; Trinquier, G.; Gadéa, F. X.

    2017-03-01

    We present dynamical studies of the dissociation of polycyclic aromatic hydrocarbon (PAH) radical cations in their ground electronic states with significant internal energy. Molecular dynamics simulations are performed, the electronic structure being described on-the-fly at the self-consistent-charge density functional-based tight binding (SCC-DFTB) level of theory. The SCC-DFTB approach is first benchmarked against DFT results. Extensive simulations are achieved for naphthalene , pyrene and coronene at several energies. Such studies enable one to derive significant trends on branching ratios, kinetics, structures and hints on the formation mechanism of the ejected neutral fragments. In particular, dependence of branching ratios on PAH size and energy were retrieved. The losses of H and C2H2 (recognized as the ethyne molecule) were identified as major dissociation channels. The H/C2H2 ratio was found to increase with PAH size and to decrease with energy. For , which is the most interesting PAH from the astrophysical point of view, the loss of H was found as the quasi-only channel for an internal energy of 30 eV. Overall, in line with experimental trends, decreasing the internal energy or increasing the PAH size will favour the hydrogen loss channels with respect to carbonaceous fragments. This article is part of the themed issue 'Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces'.

  14. Nucleobases in Space: Laboratory Studies of Polycyclic Aromatic Nitrogen Heterocycles

    Science.gov (United States)

    Elsila, Jamie; Mattioda, Andy; Bernstein, Max; Sandford, Scott; Hudgins, Doug

    2005-01-01

    Polycyclic Aromatic Nitrogen Heterocycles (PANHs) are heterocyclic aromatics Le., PAHs with carbon atoms replaced by a nitrogen atom. These molecules have been detected in meteorite extracts, and in general these nitrogen heterocycles are of astrobiological interest since this class of molecules include nucleobases, basic components of our nucleic acids. These compounds are predicted to be present in the interstellar medium and in Titan tholin, but have received relatively little attention. We will present spectra and reactions of PANHs, frozen in solid H2O at 12 K, conditions germane to astronomical observations. In contrast to simple PAHs, that do not interact strongly with solid H2O, the nitrogen atoms in PANHs are potentially capable of hydrogen bonding with H20 changing their spectra, complicating their remote detection on the surfaces of icy bodies. Moreover, we have studied the photo-chemistry of these interesting compounds under astrophysical conditions and will use our lab studies to assess a potential interstellar heritage of these compounds in carbonaceous chondrites.

  15. Polycyclic aromatic hydrocarbons in model bacterial membranes - Langmuir monolayer studies.

    Science.gov (United States)

    Broniatowski, Marcin; Binczycka, Martyna; Wójcik, Aneta; Flasiński, Michał; Wydro, Paweł

    2017-12-01

    High molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) are persistent organic pollutants which due to their limited biodegradability accumulate in soils where their increased presence can lead to the impoverishment of the decomposer organisms. As very hydrophobic PAHs easily penetrate cellular membranes of soil bacteria and can be incorporated therein, changing the membrane fluidity and other functions which in consequence can lead to the death of the organism. The structure and size of PAH molecule can be crucial for its membrane activity; however the correlation between PAH structure and its interaction with phospholipids have not been investigated so far. In our studies we applied phospholipid Langmuir monolayers as model bacterial membranes and investigated how the incorporation of six structurally different PAH molecules change the membrane texture and physical properties. In our studies we registered surface pressure and surface potential isotherms upon the monolayer compression, visualized the monolayer texture with the application of Brewster angle microscopy and searched the ordering of the film-forming molecules with molecular resolution with the application of grazing incidence X-ray diffraction (GIXD) method. It turned out that the phospholipid-PAH interactions are strictly structure dependent. Four and five-ring PAHs of the angular or cluster geometry can be incorporated into the model membranes changing profoundly their textures and fluidity; whereas linear or large cluster PAHs cannot be incorporated and separate from the lipid matrix. The observed phenomena were explained based on structural similarities of the applied PAHs with membrane steroids and hopanoids. Copyright © 2017. Published by Elsevier B.V.

  16. Theoretical studies of the structures and local aromaticity of conjugated polycyclic hydrocarbons using three aromatic indices

    Science.gov (United States)

    Sakai, Shogo; Kita, Yuki

    2013-07-01

    The structures and local aromaticity of some conjugated polycyclic hydrocarbons (from the butadienoid, acene, and phenylene series) are studied using ab initio MO and density functional methods. The aromaticities of the molecules are estimated using three indices: the nucleus-independent chemical shift (NICS), the harmonic oscillator model of aromaticity (HOMA), and the index of deviation from aromaticity (IDA). Assessment of the relationships between the structures and the aromatic indices shows that the IDA values correspond best to the characteristics of the conjugated polycyclic hydrocarbon structures.

  17. Particle in a Disk: A Spectroscopic and Computational Laboratory Exercise Studying the Polycyclic Aromatic Hydrocarbon Corannulene

    Science.gov (United States)

    Frey, E. Ramsey; Sygula, Andrzej; Hammer, Nathan I.

    2014-01-01

    This laboratory exercise introduces undergraduate chemistry majors to the spectroscopic and theoretical study of the polycyclic aromatic hydrocarbon (PAH), corannulene. Students explore the spectroscopic properties of corannulene using UV-vis and Raman vibrational spectroscopies. They compare their experimental results to simulated vibrational…

  18. Study of remobilization polycyclic aromatic hydrocarbons (PAHs) in contaminated matrices

    International Nuclear Information System (INIS)

    Belkessam, L.; Vessigaud, S.; Laboudigue, A.; Vessigaud, S.; Perrin-Ganier, C.; Schiavon, M.; Denys, S.

    2005-01-01

    Polycyclic aromatic hydrocarbons (PAHs) originate from many pyrolysis processes. They are widespread environmental pollutants because some of them present toxic and genotoxic properties. In coal pyrolysis sites such as former manufactured gas plants and coke production plants, coal tar is a major source of PAHs. The management of such sites requires better understanding of the mechanisms that control release of PAHs to the biosphere. Determining total PAH concentrations is not sufficient since it does not inform about the pollutants availability to environmental processes. The fate and transport of PAHs in soil are governed by sorption and microbial processes which are well documented. Globally, enhancing retention of the compounds by a solid matrix reduces the risk of pollutant dispersion, but decreases their accessibility to microbial microflora. Conversely, the remobilization of organics from contaminated solid matrices represents a potential hazard since these pollutants can reach groundwater resources. However the available data are often obtained from laboratory experiments in which many field parameters can not be taken into account (long term, temperature, co-pollution, ageing phenomenon, heterogenous distribution of pollution). The present work focuses on the influence assessment and understanding of some of these parameters on PAHs remobilization from heavily polluted matrices in near-field conditions (industrial contaminated matrices, high contact time, ..). Results concerning effects of temperature and physical state of pollution (dispersed among the soil or condensed in small clusters or in coal tar) are presented. (authors)

  19. Backflush HPLC for the isolation of polycyclic aromatic compounds - a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Oestman, C.E.; Colmsjoe, A.L.

    1987-12-01

    Semipreparative HPLC utilizing a polar bonded phase was applied to the isolation of polycyclic aromatic compounds (PAC) from complex samples using a backflush technique. Aminopropyl- and cyanopropyl-modified silica was tested. Aminopropyl-modified silica was found to be superior in achieving rapid, selective and non discriminating isolation of PAC. This was compared with the most commonly used isolation methods, dimethylsulfoxide (DMSO), dimethylformamide (DMF) and nitromethane liquid-liquid extractions, and silica and SephadexLH-20 open column chromatography. Strong discrimination of alkylated PAC and polycyclic aromatic nitrogen heterocyclics (PANH) was found for the liquid-liquid extractions and the LH-20 column chromatography. These comparisons were made using both standard compounds and a sample of used crank-case oil, indicating the necessity of using a real sample for evaluation of extraction methods. Recoveries of 42 PACs are reported.

  20. Stochastic fuzzy environmental risk characterization of uncertainty and variability in risk assessments: A case study of polycyclic aromatic hydrocarbons in soil at a petroleum-contaminated site in China

    International Nuclear Information System (INIS)

    Hu, Yan; Wang, Zesen; Wen, Jingya; Li, Yu

    2016-01-01

    Highlights: • Deal with environmental quality guidelines absence in risk characterization. • Quantitative represention of uncertainty from environmental quality guidelines. • Quantitative represention of variability from contaminant exposure concentrations. • Establishment of stochastic-fuzzy environmental risk characterization approach framework. - Abstract: Better decisions are made using risk assessment models when uncertainty and variability are explicitly acknowledged. Uncertainty caused by a lack of uniform and scientifically supported environmental quality guidelines and variability in the degree of exposure of environmental systems to contaminants are here incorporated in a stochastic fuzzy environmental risk characterization (SFERC) approach. The approach is based on quotient probability distribution and environmental risk level fuzzy membership function methods. The SFERC framework was used to characterize the environmental risks posed by 16 priority polycyclic aromatic hydrocarbons (PAHs) in soil at a typical petroleum-contaminated site in China. This relied on integrating data from the literature and field and laboratory experiments. The environmental risk levels posed by the PAHs under four risk scenarios were determined using the SFERC approach, using “residential land” and “industrial land” environmental quality guidelines under “loose” and “strict” strictness parameters. The results showed that environmental risks posed by PAHs in soil are primarily caused by oil exploitation, traffic emissions, and coal combustion. The SFERC approach is an effective tool for characterizing uncertainty and variability in environmental risk assessments and for managing contaminated sites.

  1. Stochastic fuzzy environmental risk characterization of uncertainty and variability in risk assessments: A case study of polycyclic aromatic hydrocarbons in soil at a petroleum-contaminated site in China

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yan [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing 100012 (China); Wang, Zesen [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Wen, Jingya [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Institute of Hydropower and Environment Research, Beijing 100012 (China); Li, Yu, E-mail: liyuxx8@hotmail.com [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China)

    2016-10-05

    Highlights: • Deal with environmental quality guidelines absence in risk characterization. • Quantitative represention of uncertainty from environmental quality guidelines. • Quantitative represention of variability from contaminant exposure concentrations. • Establishment of stochastic-fuzzy environmental risk characterization approach framework. - Abstract: Better decisions are made using risk assessment models when uncertainty and variability are explicitly acknowledged. Uncertainty caused by a lack of uniform and scientifically supported environmental quality guidelines and variability in the degree of exposure of environmental systems to contaminants are here incorporated in a stochastic fuzzy environmental risk characterization (SFERC) approach. The approach is based on quotient probability distribution and environmental risk level fuzzy membership function methods. The SFERC framework was used to characterize the environmental risks posed by 16 priority polycyclic aromatic hydrocarbons (PAHs) in soil at a typical petroleum-contaminated site in China. This relied on integrating data from the literature and field and laboratory experiments. The environmental risk levels posed by the PAHs under four risk scenarios were determined using the SFERC approach, using “residential land” and “industrial land” environmental quality guidelines under “loose” and “strict” strictness parameters. The results showed that environmental risks posed by PAHs in soil are primarily caused by oil exploitation, traffic emissions, and coal combustion. The SFERC approach is an effective tool for characterizing uncertainty and variability in environmental risk assessments and for managing contaminated sites.

  2. Study of nitro-polycyclic aromatic hydrocarbons in fine and coarse atmospheric particles

    Science.gov (United States)

    Teixeira, Elba Calesso; Garcia, Karine Oliveira; Meincke, Larissa; Leal, Karen Alam

    2011-08-01

    The purpose of the present study was to evaluate six nitro-polycyclic aromatic hydrocarbons (NPAHs) in fine (MAPA), RS, Brazil. The method used was of NPAHs isolation and derivatization, and subsequent gas chromatography by electron capture detection (CG/ECD). Results revealed a higher concentration of NPAHs, especially 3-nitrofluoranthene and 1-nitropyrene, in fine particles in the sampling sites studied within the MAPA. The diagnostic ratios calculated for PAHs and NPAHs identified the influence of heavy traffic, mainly of diesel emissions. The correlation of NPAHs with other pollutants (NO x, NO 2, NO and O 3) evidence the influence of vehicular emissions in the MAPA. The seasonal variation evidenced higher NPAHs concentrations in the fine particles during winter for most compounds studied.

  3. Geochronologic study of polycyclic rocks from Sao Vicente complex in anticlinorium of Caico and Florania - RN, Brazil

    International Nuclear Information System (INIS)

    Pessoa, D.A.R.

    1976-01-01

    The characterization of geochronologic standard in a polycyclic area, verifying the interpretative potentials of Rubidium-Strontium and Potassium-Argon methods is the main objective of this paper. The determinations of K/Ar were made in amphiboles, moscovites and biotites. Petrology studies were also made for verifying the composition of several lithological types. (author)

  4. CASE STUDY

    African Journals Online (AJOL)

    2011-06-02

    Jun 2, 2011 ... immunosuppression associated with HIV/AIDS puts them at a higher risk of developing oesophageal cancer. 47. CASE STUDY. A 49-year-old man was diagnosed as HIV infected, with a CD4 count of 60 cells/µl. He was started on an antiretroviral treatment regimen comprising zidovudine, lamivudine and ...

  5. Vehicular Traffic-Related Polycyclic Aromatic Hydrocarbon Exposure and Breast Cancer Incidence: The Long Island Breast Cancer Study Project (LIBCSP).

    Science.gov (United States)

    Mordukhovich, Irina; Beyea, Jan; Herring, Amy H; Hatch, Maureen; Stellman, Steven D; Teitelbaum, Susan L; Richardson, David B; Millikan, Robert C; Engel, Lawrence S; Shantakumar, Sumitra; Steck, Susan E; Neugut, Alfred I; Rossner, Pavel; Santella, Regina M; Gammon, Marilie D

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants, known human lung carcinogens, and potent mammary carcinogens in laboratory animals. However, the association between PAHs and breast cancer in women is unclear. Vehicular traffic is a major ambient source of PAH exposure. Our study aim was to evaluate the association between residential exposure to vehicular traffic and breast cancer incidence. Residential histories of 1,508 participants with breast cancer (case participants) and 1,556 particpants with no breast cancer (control participants) were assessed in a population-based investigation conducted in 1996-1997. Traffic exposure estimates of benzo[a]pyrene (B[a]P), as a proxy for traffic-related PAHs, for the years 1960-1995 were reconstructed using a model previously shown to generate estimates consistent with measured soil PAHs, PAH-DNA adducts, and CO readings. Associations between vehicular traffic exposure estimates and breast cancer incidence were evaluated using unconditional logistic regression. The odds ratio (95% CI) was modestly elevated by 1.44 (0.78, 2.68) for the association between breast cancer and long-term 1960-1990 vehicular traffic estimates in the top 5%, compared with below the median. The association with recent 1995 traffic exposure was elevated by 1.14 (0.80, 1.64) for the top 5%, compared with below the median, which was stronger among women with low fruit/vegetable intake [1.46 (0.89, 2.40)], but not among those with high fruit/vegetable intake [0.92 (0.53, 1.60)]. Among the subset of women with information regarding traffic exposure and tumor hormone receptor subtype, the traffic-breast cancer association was higher for those with estrogen/progesterone-negative tumors [1.67 (0.91, 3.05) relative to control participants], but lower among all other tumor subtypes [0.80 (0.50, 1.27) compared with control participants]. In our population-based study, we observed positive associations between vehicular traffic

  6. A study on the coagulation of polycyclic aromatic hydrocarbon clusters to determine their collision efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Raj, Abhijeet; Sander, Markus; Janardhanan, Vinod; Kraft, Markus [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom)

    2010-03-15

    This paper presents a theoretical study on the physical interaction between polycyclic aromatic hydrocarbons (PAHs) and their clusters of different sizes in laminar premixed flames. Two models are employed for this study: a detailed PAH growth model, referred to as the kinetic Monte Carlo - aromatic site (KMC-ARS) model [Raj et al., Combust. Flame 156 (2009) 896-913]; and a multivariate PAH population balance model, referred to as the PAH - primary particle (PAH-PP) model. Both the models are solved by kinetic Monte Carlo methods. PAH mass spectra are generated using the PAH-PP model, and compared to the experimentally observed spectra for a laminar premixed ethylene flame. The position of the maxima of PAH dimers in the spectra and their concentrations are found to depend strongly on the collision efficiency of PAH coagulation. The variation in the collision efficiency with various flame and PAH parameters is studied to determine the factors on which it may depend. A correlation for the collision efficiency is proposed by comparing the computed and the observed spectra for an ethylene flame. With this correlation, a good agreement between the computed and the observed spectra for a number of laminar premixed ethylene flames is found. (author)

  7. Vehicular Traffic?Related Polycyclic Aromatic Hydrocarbon Exposure and Breast Cancer Incidence: The Long Island Breast Cancer Study Project (LIBCSP)

    OpenAIRE

    Mordukhovich, Irina; Beyea, Jan; Herring, Amy H.; Hatch, Maureen; Stellman, Steven D.; Teitelbaum, Susan L.; Richardson, David B.; Millikan, Robert C.; Engel, Lawrence S.; Shantakumar, Sumitra; Steck, Susan E.; Neugut, Alfred I.; Rossner, Pavel; Santella, Regina M.; Gammon, Marilie D.

    2015-01-01

    Background Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants, known human lung carcinogens, and potent mammary carcinogens in laboratory animals. However, the association between PAHs and breast cancer in women is unclear. Vehicular traffic is a major ambient source of PAH exposure. Objectives Our study aim was to evaluate the association between residential exposure to vehicular traffic and breast cancer incidence. Methods Residential histories of 1,508 particip...

  8. Exploratory study of particle-bound polycyclic aromatic hydrocarbons in different environments of Mexico City

    Science.gov (United States)

    Velasco, Erik; Siegmann, Philip; Siegmann, Hans C.

    2004-09-01

    Several studies regarding particulate matter in air pollution have been performed in Mexico City, but none have focused on environment exposure to particle-bound polycyclic aromatic hydrocarbons (PPAH), which are related to the occurrence of cardiopulmonary diseases and mortality. On this account, this study presents measurements of personal exposure to PPAH in different outdoor and indoor environments, as well as along roadways in Mexico City. The measurements were done with portable sensors based on photoelectric charging and diffusion charging to determine the PPAH concentrations and the joint active surface of all particles, respectively. The use of these two sensors in parallel is a useful tool to qualitatively identify the major sources and to describe the physical and chemical characteristics of the particles. The highest exposures were found in ambient air near traffic sources, mainly at sites with great influence of diesel vehicles, such as urban transfer bus stations. Roadway measurements showed that Mexican PPAH pollution levels are between those in large cities in Europe and USA. For indoor environments such as residences, shopping centers, restaurants and hospitality venues, it was found that secondhand smoke is the major contributor, however badly calibrated pilot stoves, inefficient ventilation and faulty air-conditioning systems can be additional sources of PPAH.

  9. Study of geographical trends of polycyclic aromatic hydrocarbons using pine needles

    Science.gov (United States)

    Amigo, José Manuel; Ratola, Nuno; Alves, Arminda

    2011-10-01

    In this work, pine needles were used as polycyclic aromatic hydrocarbons (PAHs) markers to study the PAHs distribution over several geographical locations in Portugal and over time. Four pine needle sampling campaigns (winter, spring, summer and autumn 2007) were carried out in 29 sites, covering the major urban centres, some industrial points, smaller cities, rural areas and remote locations. Needles from Pinus pinaster Ait. and Pinus pinea L. trees were collected from 2005 and 2006 shoots, corresponding to one up to three years of exposure. Spatial trends of the incidence of PAHs indicate an increase from the remote to the urban and industrial sites. The mean values for the sum of 16 PAHs ranged from 96 ± 30 ng g -1 (dry weight) for remote sites to 866 ± 304 ng g -1 (dw) for industrial sites for P. pinaster needles and from 188 ± 117 ng g -1 (dw) for rural sites to 337 ± 153 ng g -1 (dw) for urban sites for P. pinea. Geographic information system tools and principal component analysis revealed that the contamination patterns of PAHs are somehow related to several socio-geographic parameters of the sampling sites. The geographical trend for the PAHs is similar between seasons in terms of PAH levels, but some diverse behaviour is found on the separation of lighter and heavier PAHs. Differences between P. pinaster and P. pinea needles are stronger in terms of PAH uptake loads than in the site type fingerprints.

  10. Removing polycyclic aromatic hydrocarbons from water using granular activated carbon: kinetic and equilibrium adsorption studies.

    Science.gov (United States)

    Eeshwarasinghe, Dinushika; Loganathan, Paripurnanda; Kalaruban, Mahatheva; Sounthararajah, Danious Pratheep; Kandasamy, Jaya; Vigneswaran, Saravanamuthu

    2018-05-01

    Polycyclic aromatic hydrocarbons (PAHs) constitute a group of highly persistent, toxic and widespread environmental micropollutants that are increasingly found in water. A study was conducted in removing five PAHs, specifically naphthalene, acenaphthylene, acenaphthene, fluorene and phenanthrene, from water by adsorption onto granular activated carbon (GAC). The pseudo-first-order (PFO) model satisfactorily described the kinetics of adsorption of the PAHs. The Weber and Morris diffusion model's fit to the data showed that there were faster and slower rates of intra-particle diffusion probably into the mesopores and micropores of the GAC, respectively. These rates were negatively related to the molar volumes of the PAHs. Batch equilibrium adsorption data fitted well to the Langmuir, Freundlich and Dubinin-Radushkevich models, of which the Freundlich model exhibited the best fit. The adsorption affinities were related to the hydrophobicity of the PAHs as determined by the log K ow values. Free energies of adsorption calculated from the Dubinin-Radushkevich model and the satisfactory kinetic data fitting to the PFO model suggested physical adsorption of the PAHs. Adsorption of naphthalene, acenaphthylene and acenaphthene in fixed-bed columns containing a mixture of GAC (0.5 g) + sand (24.5 g) was satisfactorily simulated by the Thomas model.

  11. Probing the spin multiplicity of gas-phase polycyclic aromatic hydrocarbons through their infrared emission spectrum: a theoretical study.

    Science.gov (United States)

    Falvo, Cyril; Calvo, Florent; Parneix, Pascal

    2012-08-14

    The anharmonic infrared emission spectrum following an optical excitation has been calculated for a variety of polycyclic aromatic hydrocarbon molecules in their ground singlet electronic state or in their triplet state. The computational protocol relies on second-order perturbation theory and involves a quartic vibrational Hamiltonian, the vibrational quantum numbers being sampled according to a Monte Carlo procedure. In the case of neutral naphthalene, the IR spectrum obtained in the (ground) singlet state differs significantly from the spectrum in the triplet state, especially for out-of-plane CH bending modes. Although not as prominent, spectral differences in larger molecules are still observable.

  12. Casing study

    Energy Technology Data Exchange (ETDEWEB)

    Roche, P.

    2000-12-01

    An unorthodox method of casing drilling used by Tesco Corporation at a gas well in Wyoming to drill deeper using casings as drillpipe is discussed. The process involves either rotating the casing as drill string or using a downhole mud motor to rotate the bit. In this instance, the surface hole and the production hole were casing-drilled to a record 8,312 feet by rotating the casing. The 8 1/2-inch surface hole was drilled with 7-inch casing to 1,200 feet using a Tesco underreamer and a polycrystalline pilot bit; drilling and cementing was completed in 12 1/2 hours. The 6 1/4-inch production hole was drilled with 4 1/2-inch casing and the bottomhole assembly was retrieved after 191 hours rotating. This case was the first in which the entire well was casing-drilled from surface to TD. Penetration rate compared favorably with conventional methods: 12 1/2 hours for casing-drilling to 18.9 hours for conventional drilling, despite the fact that the casing-drilling technology is still in its infancy. It is suggested that casing-drilling has the potential to eliminate the need for the drillpipe entirely. If these expectations were to be realised, casing-drilling could be one of the most radical drilling changes in the history of the oil and gas industry. 1 photo.

  13. Rotation-vibration interactions in the spectra of polycyclic aromatic hydrocarbons: Quinoline as a test-case species

    International Nuclear Information System (INIS)

    Pirali, O.; Gruet, S.; Kisiel, Z.; Goubet, M.; Martin-Drumel, M. A.; Cuisset, A.; Hindle, F.; Mouret, G.

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are highly relevant for astrophysics as possible, though controversial, carriers of the unidentified infrared emission bands that are observed in a number of different astronomical objects. In support of radio-astronomical observations, high resolution laboratory spectroscopy has already provided the rotational spectra in the vibrational ground state of several molecules of this type, although the rotational study of their dense infrared (IR) bands has only recently become possible using a limited number of experimental set-ups. To date, all of the rotationally resolved data have concerned unperturbed spectra. We presently report the results of a high resolution study of the three lowest vibrational states of quinoline C 9 H 7 N, an N-bearing naphthalene derivative. While the pure rotational ground state spectrum of quinoline is unperturbed, severe complications appear in the spectra of the ν 45 and ν 44 vibrational modes (located at about 168 cm −1 and 178 cm −1 , respectively). In order to study these effects in detail, we employed three different and complementary experimental techniques: Fourier-transform microwave spectroscopy, millimeter-wave spectroscopy, and Fourier-transform far-infrared spectroscopy with a synchrotron radiation source. Due to the high density of states in the IR spectra of molecules as large as PAHs, perturbations in the rotational spectra of excited states should be ubiquitous. Our study identifies for the first time this effect and provides some insights into an appropriate treatment of such perturbations

  14. Rotation-vibration interactions in the spectra of polycyclic aromatic hydrocarbons: Quinoline as a test-case species

    Science.gov (United States)

    Pirali, O.; Kisiel, Z.; Goubet, M.; Gruet, S.; Martin-Drumel, M. A.; Cuisset, A.; Hindle, F.; Mouret, G.

    2015-03-01

    Polycyclic aromatic hydrocarbons (PAHs) are highly relevant for astrophysics as possible, though controversial, carriers of the unidentified infrared emission bands that are observed in a number of different astronomical objects. In support of radio-astronomical observations, high resolution laboratory spectroscopy has already provided the rotational spectra in the vibrational ground state of several molecules of this type, although the rotational study of their dense infrared (IR) bands has only recently become possible using a limited number of experimental set-ups. To date, all of the rotationally resolved data have concerned unperturbed spectra. We presently report the results of a high resolution study of the three lowest vibrational states of quinoline C9H7N, an N-bearing naphthalene derivative. While the pure rotational ground state spectrum of quinoline is unperturbed, severe complications appear in the spectra of the ν45 and ν44 vibrational modes (located at about 168 cm-1 and 178 cm-1, respectively). In order to study these effects in detail, we employed three different and complementary experimental techniques: Fourier-transform microwave spectroscopy, millimeter-wave spectroscopy, and Fourier-transform far-infrared spectroscopy with a synchrotron radiation source. Due to the high density of states in the IR spectra of molecules as large as PAHs, perturbations in the rotational spectra of excited states should be ubiquitous. Our study identifies for the first time this effect and provides some insights into an appropriate treatment of such perturbations.

  15. A MOLECULAR DYNAMICS STUDY ON SLOW ION INTERACTIONS WITH THE POLYCYCLIC AROMATIC HYDROCARBON MOLECULE ANTHRACENE

    NARCIS (Netherlands)

    Postma, J.; Hoekstra, Ronnie; Tielens, A. G. G. M.; Schlathölter, Thomas

    2014-01-01

    Atomic collisions with polycyclic aromatic hydrocarbon (PAH) molecules are astrophysically particularly relevant for collision energies of less than 1 keV. In this regime, the interaction dynamics are dominated by elastic interactions. We have employed a molecular dynamics simulation based on

  16. A computational study of ethylene–air sooting flames: Effects of large polycyclic aromatic hydrocarbons

    KAUST Repository

    Selvaraj, Prabhu; Arias, Paul G.; Lee, Bok Jik; Im, Hong G.; Wang, Yu; Gao, Yang; Park, Sungwoo; Sarathy, Mani; Lu, Tianfeng; Chung, Suk-Ho

    2015-01-01

    formation to various chemical pathways for large polycyclic aromatic hydrocarbons (PAH). The gas-phase chemical mechanism adopted the KAUST-Aramco PAH Mech 1.0, which utilized the AramcoMech 1.3 for gas-phase reactions validated for up to C2 fuels

  17. A numerical and experimental study of polycyclic aromatic hydrocarbons in a laminar diffusion flame

    NARCIS (Netherlands)

    Vogels - Verhoeven, L.M.; Andrade Oliveira, de M.H.; Lantz, A.; Li, B.; Li, Z.S.; Luijten, C.C.M.; Oijen, van J.A.; Aldén, M.; Goey, de L.P.H.

    2013-01-01

    During the process of biomass gasification tars are formed which exit the gasifier in vapor phase. Tar condensation creates problems like fouling and plugging of after-treatment, conversion and end-use equipment. Gasification tars consist mainly of Polycyclic Aromatic Hydrocarbons (PAHs). Former

  18. CASE STUDY

    African Journals Online (AJOL)

    HIV infection has several oral manifestations, including oral candidiasis and oral hairy leucoplakia. Occasionally unusual presentations requiring rigorous investigations are seen, and in these cases the diagnosis sometimes remains a dilemma owing to limited investigation facilities.1-3 We present the case of a patient who.

  19. A computational study of ethylene–air sooting flames: Effects of large polycyclic aromatic hydrocarbons

    KAUST Repository

    Selvaraj, Prabhu

    2015-11-05

    An updated reduced gas-phase kinetic mechanism was developed and integrated with aerosol models to predict soot formation characteristics in ethylene nonpremixed and premixed flames. A primary objective is to investigate the sensitivity of the soot formation to various chemical pathways for large polycyclic aromatic hydrocarbons (PAH). The gas-phase chemical mechanism adopted the KAUST-Aramco PAH Mech 1.0, which utilized the AramcoMech 1.3 for gas-phase reactions validated for up to C2 fuels. In addition, PAH species up to coronene (C24H12 or A7) were included to describe the detailed formation pathways of soot precursors. In this study, the detailed chemical mechanism was reduced from 397 to 99 species using directed relation graph with expert knowledge (DRG-X) and sensitivity analysis. The method of moments with interpolative closure (MOMIC) was employed for the soot aerosol model. Counterflow nonpremixed flames at low strain rate sooting conditions were considered, for which the sensitivity of soot formation characteristics to different nucleation pathways were investigated. Premixed flame experiment data at different equivalence ratios were also used for validation. The findings show that higher PAH concentrations result in a higher soot nucleation rate, and that the total soot volume and average size of the particles are predicted in good agreement with experimental results. Subsequently, the effects of different pathways, with respect to pyrene- or coronene-based nucleation models, on the net soot formation rate were analyzed. It was found that the nucleation processes (i.e., soot inception) are sensitive to the choice of PAH precursors, and consideration of higher PAH species beyond pyrene is critical for accurate prediction of the overall soot formation.

  20. Rotation-vibration interactions in the spectra of polycyclic aromatic hydrocarbons: Quinoline as a test-case species

    Energy Technology Data Exchange (ETDEWEB)

    Pirali, O.; Gruet, S. [AILES Beamline, Synchrotron SOLEIL, l’Orme des Merisiers, Saint-Aubin, 91192 Gif-sur-Yvette cedex (France); Institut des Sciences Moléculaires d’Orsay, UMR8214 CNRS – Université Paris-Sud, Bât. 210, 91405 Orsay cedex (France); Kisiel, Z. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland); Goubet, M. [Laboratoire de Physique des Lasers, Atomes et Molécules, UMR 8523 CNRS - Université Lille 1, Bâtiment P5, F-59655 Villeneuve d’Ascq Cedex (France); Martin-Drumel, M. A.; Cuisset, A.; Hindle, F.; Mouret, G. [Laboratoire de Physico-Chimie de l’Atmosphère, EA-4493, Université du Littoral – Côte d’Opale, 59140 Dunkerque (France)

    2015-03-14

    Polycyclic aromatic hydrocarbons (PAHs) are highly relevant for astrophysics as possible, though controversial, carriers of the unidentified infrared emission bands that are observed in a number of different astronomical objects. In support of radio-astronomical observations, high resolution laboratory spectroscopy has already provided the rotational spectra in the vibrational ground state of several molecules of this type, although the rotational study of their dense infrared (IR) bands has only recently become possible using a limited number of experimental set-ups. To date, all of the rotationally resolved data have concerned unperturbed spectra. We presently report the results of a high resolution study of the three lowest vibrational states of quinoline C{sub 9}H{sub 7}N, an N-bearing naphthalene derivative. While the pure rotational ground state spectrum of quinoline is unperturbed, severe complications appear in the spectra of the ν{sub 45} and ν{sub 44} vibrational modes (located at about 168 cm{sup −1} and 178 cm{sup −1}, respectively). In order to study these effects in detail, we employed three different and complementary experimental techniques: Fourier-transform microwave spectroscopy, millimeter-wave spectroscopy, and Fourier-transform far-infrared spectroscopy with a synchrotron radiation source. Due to the high density of states in the IR spectra of molecules as large as PAHs, perturbations in the rotational spectra of excited states should be ubiquitous. Our study identifies for the first time this effect and provides some insights into an appropriate treatment of such perturbations.

  1. case study

    African Journals Online (AJOL)

    Elton

    particularly in patients who commence ART with low CD4 counts and established opportunistic infections. IRIS results from a pathological inflammatory response to pre-existing infective, host or other antigens, alive or dead, causing clinical deterioration in HIV-infected patients after initiating ART.1 A case definition for IRIS ...

  2. CASE STUDY

    African Journals Online (AJOL)

    2010-09-01

    Sep 1, 2010 ... of the two diseases surgery can be successful, recovery can be similar to that .... lymphocytes predominated in 68% of cases, and that there was an .... using ferritin is the fact that it acts as an acute-phase reactant and will be ...

  3. The Composition of Cigarette Smoke: A Chronology of the Studies of Four Polycyclic Aromatic Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Rodgman A

    2014-12-01

    Full Text Available Among the polycyclic aromatic hydrocarbons (PAHs, a major class of identified cigarette mainstream smoke (MSS components, are several shown to be tumorigenic in laboratory animals and suspect as possible tumorigens to humans. To date, nearly 540 PAHs have been completely or partially identified in tobacco smoke [Rodgman and Perfetti (1]. A detailed chronology is presented of studies on four much discussed PAHs identified in tobacco smoke, namely, benz[a]anthracene (B[a]A, its 7,12-dimethyl derivative (DMB[a]A, dibenz[a, h]anthracene (DB[a, h]A, and benzo[a]pyrene (B[a]P. Of the four, DMB[a]A, DB[a, h]A, and B[a]P are considered to be potently tumorigenic on mouse skin painting and subcutaneous injection. Opinions on the tumorigenicity of B[a]A to mouse skin vary. DMB[a]A is frequently used in tumorigenicity studies as an initiator. Examination of the number of tobacco smoke-related citations listed for these four PAHs reveals the enormous effort devoted since the early 1950s to B[a]P vs. the other three. An annotated chronology from 1886 to date describes the tobacco smoke-related research pertinent to these four PAHs, their discovery, isolation and/or identification, quantitation, and contribution to the observed biological activity of MSS or cigarette smoke condensate (CSC. Much of the major literature on these four PAHs in tobacco smoke is presented in order to permit the reader to decide whether the current evidence is sufficient to classify them as a health risk to smokers. There has certainly been a tremendous effort by researchers to learn about these PAHs over the past several decades. Each of these PAHs when tested individually has been shown to possess the following biological properties: 1 Mutagenicity in certain bacterial situations, 2 tumorigenicity in certain animal species, to varying degrees under various administration modes, and 3 a threshold limit below which no tumorigenesis occurs. For more than five decades, it has been

  4. Case Study: Testing with Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman

    2015-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses using case studies to test for knowledge or lessons learned.

  5. Bioactivity Studies of β-Lactam Derived Polycyclic Fused Pyrroli-Dine/Pyrrolizidine Derivatives in Dentistry: In Vitro, In Vivo and In Silico Studies.

    Directory of Open Access Journals (Sweden)

    Gowri Meiyazhagan

    Full Text Available The antibacterial activity of β-lactam derived polycyclic fused pyrrolidine/pyrrolizidine derivatives synthesized by 1, 3-dipolar cycloaddition reaction was evaluated against microbes involved in dental infection. Fifteen compounds were screened; among them compound 3 showed efficient antibacterial activity in an ex vivo dentinal tubule model and in vivo mice infectious model. In silico docking studies showed greater affinity to penicillin binding protein. Cell damage was observed under Scanning Electron Microscopy (SEM which was further proved by Confocal Laser Scanning Microscope (CLSM and quantified using Flow Cytometry by PI up-take. Compound 3 treated E. faecalis showed ROS generation and loss of membrane integrity was quantified by flow cytometry. Compound 3 was also found to be active against resistant E. faecalis strains isolated from failed root canal treatment cases. Further, compound 3 was found to be hemocompatible, not cytotoxic to normal mammalian NIH 3T3 cells and non mutagenic. It was concluded that β-lactam compound 3 exhibited promising antibacterial activity against E. faecalis involved in root canal infections and the mechanism of action was deciphered. The results of this research can be further implicated in the development of potent antibacterial medicaments with applications in dentistry.

  6. Bioactivity Studies of β-Lactam Derived Polycyclic Fused Pyrroli-Dine/Pyrrolizidine Derivatives in Dentistry: In Vitro, In Vivo and In Silico Studies

    Science.gov (United States)

    Winfred, Sofi Beaula; Mannivanan, Bhavani; Bhoopalan, Hemadev; Shankar, Venkatesh; Sekar, Sathiya; Venkatachalam, Deepa Parvathi; Pitani, Ravishankar; Nagendrababu, Venkateshbabu; Thaiman, Malini; Devivanayagam, Kandaswamy; Jayaraman, Jeyakanthan; Ragavachary, Raghunathan; Venkatraman, Ganesh

    2015-01-01

    The antibacterial activity of β-lactam derived polycyclic fused pyrrolidine/pyrrolizidine derivatives synthesized by 1, 3-dipolar cycloaddition reaction was evaluated against microbes involved in dental infection. Fifteen compounds were screened; among them compound 3 showed efficient antibacterial activity in an ex vivo dentinal tubule model and in vivo mice infectious model. In silico docking studies showed greater affinity to penicillin binding protein. Cell damage was observed under Scanning Electron Microscopy (SEM) which was further proved by Confocal Laser Scanning Microscope (CLSM) and quantified using Flow Cytometry by PI up-take. Compound 3 treated E. faecalis showed ROS generation and loss of membrane integrity was quantified by flow cytometry. Compound 3 was also found to be active against resistant E. faecalis strains isolated from failed root canal treatment cases. Further, compound 3 was found to be hemocompatible, not cytotoxic to normal mammalian NIH 3T3 cells and non mutagenic. It was concluded that β-lactam compound 3 exhibited promising antibacterial activity against E. faecalis involved in root canal infections and the mechanism of action was deciphered. The results of this research can be further implicated in the development of potent antibacterial medicaments with applications in dentistry. PMID:26185985

  7. Polycyclic Aromatic Hydrocarbons Adsorption onto Graphene: A DFT and AIMD Study

    Directory of Open Access Journals (Sweden)

    Bing Li

    2018-05-01

    Full Text Available Density functional theory (DFT calculations and ab-initio molecular dynamics (AIMD simulations were performed to understand graphene and its interaction with polycyclic aromatic hydrocarbons (PAHs molecules. The adsorption energy was predicted to increase with the number of aromatic rings in the adsorbates, and linearly correlate with the hydrophobicity of PAHs. Additionally, the analysis of the electronic properties showed that PAHs behave as mild n-dopants and introduce electrons into graphene; but do not remarkably modify the band gap of graphene, indicating that the interaction between PAHs and graphene is physisorption. We have also discovered highly sensitive strain dependence on the adsorption strength of PAHs onto graphene surface. The AIMD simulation indicated that a sensitive and fast adsorption process of PAHs can be achieved by choosing graphene as the adsorbent. These findings are anticipated to shed light on the future development of graphene-based materials with potential applications in the capture and removal of persistent aromatic pollutants.

  8. WHY DOES 5-METHYL CHRYSENE INTERACT WITH DNA LIKE BOTH A PLANAR AND A NON-PLANAR POLYCYCLIC AROMATIC HYDROCARBON? QUANTUM MECHANICAL STUDIES

    Science.gov (United States)

    Polycyclic aromatic hydrocarbons are a large class of anthropogenic chemicals found in the environment. Some class members are potent animal carcinogens while other similar class members show little carcinogenic activity. When considering a series of in vitro studies of the int...

  9. Sediment baseline study of levels and sources of polycyclic aromatic hydrocarbons and heavy metals in Lake Nicaragua

    DEFF Research Database (Denmark)

    Scheibye, Katrine; Weisser, Johan Juhl; Borggaard, Ole K.

    2014-01-01

    Selected metals and polycyclic aromatic hydrocarbons (PAHs) were analyzed in sediment samples from 24 sites in Lake Nicaragua sampled May 2010 to provide a baseline of pollution levels. Cu exceeded the Consensus-Based Sediment Quality Guideline (CBSQG) Threshold Effect Concentrations (TECs) at 21...... showed that the CBSQG TECs were exceeded by naphthalene at five sites. The sum concentrations of the 16 US EPA priority PAHs (∑PAH16) ranged from 0.01mgkg(-1)dw to 0.64mgkg(-1)dw. The highest ∑PAH16 concentration was found upstream in River Mayales and the PAH composition revealed a heavy PAH fraction (e....... This study concluded that areas of Lake Nicaragua represent an important pollution baseline for future studies in this lake and other tropical lakes....

  10. CASE STUDY CRITIQUE; UPPER CLINCH CASE STUDY

    Science.gov (United States)

    Case study critique: Upper Clinch case study (from Research on Methods for Integrating Ecological Economics and Ecological Risk Assessment: A Trade-off Weighted Index Approach to Integrating Economics and Ecological Risk Assessment). This critique answers the questions: 1) does ...

  11. Receptor modelling study of polycyclic aromatic hydrocarbons in Jeddah, Saudi Arabia.

    Science.gov (United States)

    Alghamdi, Mansour A; Alam, Mohammed S; Yin, Jianxin; Stark, Christopher; Jang, Eunhwa; Harrison, Roy M; Shamy, Magdy; Khoder, Mamdouh I; Shabbaj, Ibrahim I

    2015-02-15

    Measurements of 14 polycyclic aromatic hydrocarbons (PAH) have been made in Jeddah, Saudi Arabia, with a view to establishing the concentrations in this major city, and quantifying the contributions of major sources. Particulate and vapour forms have been sampled and analysed separately. The concentrations are compared to measurements from other sites in the Middle Eastern region and are towards the lower end of the range, being far lower than concentrations reported from Riyadh (Saudi Arabia), Assiut (Egypt) and Tehran (Iran) but broadly similar to those measured in Damascus (Syria) and higher than those measured in Kuwait. The partitioning between vapour and particle phases is similar to that in data from Egypt and China, but with many compounds showing a higher particle-associated percentage than in Birmingham (UK) possibly reflecting a higher concentration of airborne particulate matter in the former countries. Concentrations in Jeddah were significantly higher at a site close to the oil refinery and a site close to a major ring road than at a suburban site to the north of the city. Application of positive matrix factorisation to the pooled data elicited three factors accounting respectively for 17%, 33% and 50% of the measured sum of PAH and these are interpreted as arising from gasoline vehicles, industrial sources, particularly the oil refinery, and to diesel/fuel oil combustion. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Laboratory studies of the remediation of polycyclic aromatic hydrocarbon contaminated soil by in-vessel composting

    International Nuclear Information System (INIS)

    Antizar-Ladislao, Blanca; Lopez-Real, Joseph; Beck, Angus J.

    2005-01-01

    The biodegradation of 16 polycyclic aromatic hydrocarbons (PAHs), listed as priority pollutants by the USEPA, present in a coal-tar-contaminated soil from a former manufactured gas plant site was investigated using laboratory-scale in-vessel composting reactors to determine the suitability of this approach as a bioremediation technology. Preliminary investigations were conducted over 16 weeks to determine the optimum soil composting temperature (38, 55 and 70 deg. C). Three tests were performed; firstly, soil was composted with green-waste, with a moisture content of 60%. Secondly, microbial activity was HgCl 2 -inhibited in the soil green-waste mixture with a moisture content of 60%, to evaluate abiotic losses, while in the third experiment only soil was incubated at the three different temperatures. PAHs and microbial populations were monitored. PAHs were lost from all treatments with 38 deg. C being the optimum temperature for both PAH removal and microbial activity. Calculated activation energy values (E a ) for total PAHs suggested that the main loss mechanism in the soil-green waste reactors was biological, whereas in the soil reactors it was chemical. Total PAH losses in the soil-green waste composting mixtures were by pseudo-first order kinetics at 38 deg. C (k = 0.013 day -1 , R 2 = 0.95), 55 deg. C (k = 0.010 day -1 , R 2 = 0.76) and at 70 deg. C (k = 0.009 day -1 , R 2 = 0.73)

  13. Removal of polycyclic aromatic hydrocarbons from aged-contaminated soil using cyclodextrins: Experimental study

    International Nuclear Information System (INIS)

    Viglianti, Christophe; Hanna, Khalil; Brauer, Christine de; Germain, Patrick

    2006-01-01

    The removal of polycyclic aromatic hydrocarbons (PAHs) from soil using water as flushing agent is relatively ineffective due to their low aqueous solubility. However, addition of cyclodextrin (CD) in washing solutions has been shown to increase the removal efficiency several times. Herein are investigated the effectiveness of cyclodextrin to remove PAH occurring in industrially aged-contaminated soil. β-Cyclodextrin (BCD), hydroxypropyl-β-cyclodextrin (HPCD) and methyl-β-cyclodextrin (MCD) solutions were used for soil flushing in column test to evaluate some influent parameters that can significantly increase the removal efficiency. The process parameters chosen were CD concentration, ratio of washing solution volume to soil weight, and temperature of washing solution. These parameters were found to have a significant and almost linear effect on PAH removal from the contaminated soil, except the temperature where no significant enhancement in PAH extraction was observed for temperature range from 5 to 35 o C. The PAHs extraction enhancement factor compared to water was about 200. - An innovative method using a biodegradable and non-toxic flushing agent for the depollution of industrially aged-contaminated soil

  14. Double-tagged fluorescent bacterial bioreporter for the study of polycyclic aromatic hydrocarbon diffusion and bioavailability.

    Science.gov (United States)

    Tecon, Robin; Binggeli, Olivier; van der Meer, Jan R

    2009-09-01

    Bacterial degradation of polycyclic aromatic hydrocarbons (PAHs), ubiquitous contaminants from oil and coal, is typically limited by poor accessibility of the contaminant to the bacteria. In order to measure PAH availability in complex systems, we designed a number of diffusion-based assays with a double-tagged bacterial reporter strain Burkholderia sartisoli RP037-mChe. The reporter strain is capable of mineralizing phenanthrene (PHE) and induces the expression of enhanced green fluorescent protein (eGFP) as a function of the PAH flux to the cell. At the same time, it produces a second autofluorescent protein (mCherry) in constitutive manner. Quantitative epifluorescence imaging was deployed in order to record reporter signals as a function of PAH availability. The reporter strain expressed eGFP proportionally to dosages of naphthalene or PHE in batch liquid cultures. To detect PAH diffusion from solid materials the reporter cells were embedded in 2 cm-sized agarose gel patches, and fluorescence was recorded over time for both markers as a function of distance to the PAH source. eGFP fluorescence gradients measured on known amounts of naphthalene or PHE served as calibration for quantifying PAH availability from contaminated soils. To detect reporter gene expression at even smaller diffusion distances, we mixed and immobilized cells with contaminated soils in an agarose gel. eGFP fluorescence measurements confirmed gel patch diffusion results that exposure to 2-3 mg lampblack soil gave four times higher expression than to material contaminated with 10 or 1 (mg PHE) g(-1).

  15. Receptor modelling study of polycyclic aromatic hydrocarbons in Jeddah, Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Alghamdi, Mansour A. [Department of Environmental Sciences, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah (Saudi Arabia); Alam, Mohammed S., E-mail: m.s.alam@bham.ac.uk [Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Yin, Jianxin; Stark, Christopher; Jang, Eunhwa [Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Harrison, Roy M., E-mail: r.m.harrison@bham.ac.uk [Department of Environmental Sciences, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah (Saudi Arabia); Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Shamy, Magdy; Khoder, Mamdouh I.; Shabbaj, Ibrahim I. [Department of Environmental Sciences, Faculty of Meteorology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah (Saudi Arabia)

    2015-02-15

    Measurements of 14 polycyclic aromatic hydrocarbons (PAH) have been made in Jeddah, Saudi Arabia, with a view to establishing the concentrations in this major city, and quantifying the contributions of major sources. Particulate and vapour forms have been sampled and analysed separately. The concentrations are compared to measurements from other sites in the Middle Eastern region and are towards the lower end of the range, being far lower than concentrations reported from Riyadh (Saudi Arabia), Assiut (Egypt) and Tehran (Iran) but broadly similar to those measured in Damascus (Syria) and higher than those measured in Kuwait. The partitioning between vapour and particle phases is similar to that in data from Egypt and China, but with many compounds showing a higher particle-associated percentage than in Birmingham (UK) possibly reflecting a higher concentration of airborne particulate matter in the former countries. Concentrations in Jeddah were significantly higher at a site close to the oil refinery and a site close to a major ring road than at a suburban site to the north of the city. Application of positive matrix factorisation to the pooled data elicited three factors accounting respectively for 17%, 33% and 50% of the measured sum of PAH and these are interpreted as arising from gasoline vehicles, industrial sources, particularly the oil refinery, and to diesel/fuel oil combustion. - Highlights: • Measurements of 14 PAH compounds in vapour and particulate phases at three sites. • Comparison of concentrations across Jeddah and Middle Eastern regions. • Application of positive matrix factorisation to identify possible sources.

  16. Double-tagged fluorescent bacterial bioreporter for the study of polycyclic aromatic hydrocarbon diffusion and bioavailability

    Energy Technology Data Exchange (ETDEWEB)

    Tecon, R.; Binggeli, O.; van der Meer, J.R. [University of Lausanne, Lausanne (Switzerland). Dept. of Fundamental Microbiology

    2009-09-15

    Bacterial degradation of polycyclic aromatic hydrocarbons (PAHs), ubiquitous contaminants from oil and coal, is typically limited by poor accessibility of the contaminant to the bacteria. In order to measure PAH availability in complex systems, we designed a number of diffusion-based assays with a double-tagged bacterial reporter strain Burkholderia sartisoli RP037-mChe. The reporter strain is capable of mineralizing phenanthrene (PHE) and induces the expression of enhanced green fluorescent protein (eGFP) as a function of the PAH flux to the cell. At the same time, it produces a second autofluorescent protein (mCherry) in constitutive manner. Quantitative epifluorescence imaging was deployed in order to record reporter signals as a function of PAH availability. The reporter strain expressed eGFP proportionally to dosages of naphthalene or PHE in batch liquid cultures. To detect PAH diffusion from solid materials the reporter cells were embedded in 2 cm-sized agarose gel patches, and fluorescence was recorded over time for both markers as a function of distance to the PAH source. eGFP fluorescence gradients measured on known amounts of naphthalene or PHE served as calibration for quantifying PAH availability from contaminated soils. To detect reporter gene expression at even smaller diffusion distances, we mixed and immobilized cells with contaminated soils in an agarose gel. eGFP fluorescence measurements confirmed gel patch diffusion results that exposure to 2-3 mg lampblack soil gave four times higher expression than to material contaminated with 10 or 1 (mg PHE) g{sup -1}.

  17. Receptor modelling study of polycyclic aromatic hydrocarbons in Jeddah, Saudi Arabia

    International Nuclear Information System (INIS)

    Alghamdi, Mansour A.; Alam, Mohammed S.; Yin, Jianxin; Stark, Christopher; Jang, Eunhwa; Harrison, Roy M.; Shamy, Magdy; Khoder, Mamdouh I.; Shabbaj, Ibrahim I.

    2015-01-01

    Measurements of 14 polycyclic aromatic hydrocarbons (PAH) have been made in Jeddah, Saudi Arabia, with a view to establishing the concentrations in this major city, and quantifying the contributions of major sources. Particulate and vapour forms have been sampled and analysed separately. The concentrations are compared to measurements from other sites in the Middle Eastern region and are towards the lower end of the range, being far lower than concentrations reported from Riyadh (Saudi Arabia), Assiut (Egypt) and Tehran (Iran) but broadly similar to those measured in Damascus (Syria) and higher than those measured in Kuwait. The partitioning between vapour and particle phases is similar to that in data from Egypt and China, but with many compounds showing a higher particle-associated percentage than in Birmingham (UK) possibly reflecting a higher concentration of airborne particulate matter in the former countries. Concentrations in Jeddah were significantly higher at a site close to the oil refinery and a site close to a major ring road than at a suburban site to the north of the city. Application of positive matrix factorisation to the pooled data elicited three factors accounting respectively for 17%, 33% and 50% of the measured sum of PAH and these are interpreted as arising from gasoline vehicles, industrial sources, particularly the oil refinery, and to diesel/fuel oil combustion. - Highlights: • Measurements of 14 PAH compounds in vapour and particulate phases at three sites. • Comparison of concentrations across Jeddah and Middle Eastern regions. • Application of positive matrix factorisation to identify possible sources

  18. A study on the separation and extraction of polycyclic aromatic hydrocarbons in water sample by gas chromatography/mass spectrometry

    International Nuclear Information System (INIS)

    Lee, Won; Hong, Jee Eun; Park, Song Ja; Pyo, Hee Soo; Kim, In Hwan

    1998-01-01

    The separation and sample extraction methods of 19 polycyclic aromatic hydrocarbons (PAH S ) in water samples were investigated by gas chromatography/mass spectrometry (GC/MS) and some ex-traction methods involved liquid-liquid extraction, disk extraction and solid-phase extraction methods. The separation of 19 PAH s was possible by partial variation of oven temperature of GC/MS in temperature range 80∼310.deg.C. Extraction procedures of PAH s in water samples were somewhat modified and com-pared as extraction recoveries and the simplicity of methods. Extraction recoveries of PAH s were 71.3∼109.5% by liquid-liquid extraction method. By using disk extraction, good extraction recoveries (80.7∼94.9%) were obtained in case of C 1 8 disk extraction method by filtration. And extraction recoveries of PAH s by C 1 8 solid-phase were in the range of 51.8∼77.9%. Method detection limits (S/N=5) of 19 PAH s were in the range of 0.25∼6.25 ppb by liquid-liquid extraction and solid-phase extraction and 0.05∼1.25 ppb by disk extraction methods

  19. Polycyclic aromatic hydrocarbons and molecular hydrogen in oxygen-rich planetary nebulae: the case of NGC 6720.

    Science.gov (United States)

    Cox, N L J; Pilleri, P; Berné, O; Cernicharo, J; Joblin, C

    2016-02-11

    Evolved stars are primary sources for the formation of polycyclic aromatic hydrocarbons (PAHs) and dust grains. Their circumstellar chemistry is usually designated as either oxygen-rich or carbon-rich, although dual-dust chemistry objects, whose infrared spectra reveal both silicate- and carbon-dust features, are also known. The exact origin and nature of this dual-dust chemistry is not yet understood. Spitzer -IRS mid-infrared spectroscopic imaging of the nearby, oxygen-rich planetary nebula NGC 6720 reveals the presence of the 11.3 μ m aromatic (PAH) emission band. It is attributed to emission from neutral PAHs, since no band is observed in the 7-8 μ m range. The spatial distribution of PAHs is found to closely follow that of the warm clumpy molecular hydrogen emission. Emission from both neutral PAHs and warm H 2 is likely to arise from photo-dissociation regions associated with dense knots that are located within the main ring. The presence of PAHs together with the previously derived high abundance of free carbon (relative to CO) suggest that the local conditions in an oxygen-rich environment can also become conducive to in-situ formation of large carbonaceous molecules, such as PAHs, via a bottom-up chemical pathway. In this scenario, the same stellar source can enrich the interstellar medium with both oxygen-rich dust and large carbonaceous molecules.

  20. Pollution and pollution tolerance in the case of polycyclic aromatic hydrocarbons (PAH); Belastung durch Polyzyklische aromatische Kohlenwasserstoffe (PAK)

    Energy Technology Data Exchange (ETDEWEB)

    Renger, M.; Mekiffer, B. [Technische Univ. Berlin (Germany). Inst. fuer Oekologie-Bodenkunde

    1997-12-31

    The purpose of the present follow-up project was to examine the contamination with polycyclic aromatic hydrocarbons (PAH) of different anthropogenic urban soils including clay soils containing demolition waste, household waste, ash, and residues from a coking plant. A further task was to analyse, or infer from other part-projects, standard soil parameters such as organic carbon content, pH, and anion levels in order to clarify any relationships between PAH contamination and the more easily determinable soil characteristics. Furthermore, the sorption behaviour for PAH of selected anthropogenic urban soils was to be characterised by means of batch experiments. [Deutsch] Im Rahmen des Anschlussvorhabens sollte die Kontamination von anthropogenen Stadtboeden- darunter Truemmerschutt-, Hausmuell-, Asche- sowie Kokereilehmboden- durch polyzyklische aromatische Kohlenwasserstoffe (PAK) untersucht werden. Zusaetzlich sollten die bodenkundlichen Standardparameter Corg, pH-Wert, Anionengehalte und KAKpot analysiert bzw. von den anderen Teilvorhaben uebernommen werden, um Zusammenhaenge zwischen der PAK-Kontamination und relativ leicht zu bestimmenden bodenkundlichen Kennwerten klaeren zu koennen. Das Sorptionsverhalten ausgewaehlter anthropogener Stadtboeden fuer PAK sollte durch Batchversuche charakterisiert werden. (orig./SR)

  1. Project management case studies

    CERN Document Server

    Kerzner, Harold R

    2013-01-01

    A new edition of the most popular book of project management case studies, expanded to include more than 100 cases plus a ""super case"" on the Iridium Project Case studies are an important part of project management education and training. This Fourth Edition of Harold Kerzner''s Project Management Case Studies features a number of new cases covering value measurement in project management. Also included is the well-received ""super case,"" which covers all aspects of project management and may be used as a capstone for a course. This new edition:Contains 100-plus case studies drawn from re

  2. Case Study Research Methodology

    Directory of Open Access Journals (Sweden)

    Mark Widdowson

    2011-01-01

    Full Text Available Commenting on the lack of case studies published in modern psychotherapy publications, the author reviews the strengths of case study methodology and responds to common criticisms, before providing a summary of types of case studies including clinical, experimental and naturalistic. Suggestions are included for developing systematic case studies and brief descriptions are given of a range of research resources relating to outcome and process measures. Examples of a pragmatic case study design and a hermeneutic single-case efficacy design are given and the paper concludes with some ethical considerations and an exhortation to the TA community to engage more widely in case study research.

  3. Polycyclic aromatic hydrocarbons - fate and long-range atmospheric transport studied using a global model, EMAC-SVOC

    Science.gov (United States)

    Octaviani, Mega; Tost, Holger; Lammel, Gerhard

    2017-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are emitted by incomplete combustion from fossil fuel, vehicles, and biomass burning. They may persist in environmental compartments, pose a health hazard and may bio accumulate along food chains. The ECHAM/MESSy Atmospheric Chemistry (EMAC) model had been used to simulate global tropospheric, stratospheric chemistry and climate. In this study, we improve the model to include simulations of the transport and fate of semi-volatile organic compounds (SVOC). The EMAC-SVOC model takes into account essential environmental processes including gas-particle partitioning, dry and wet deposition, chemical and bio-degradation, and volatilization from sea surface, soils, vegetation, and snow. The model was evaluated against observational data in the Arctic, mid-latitudes, and tropics, and further applied to study total environmental lifetime and long-range transport potential (LRTP) of PAHs. We selected four compounds for study, spanning a wide range of volatility, i.e., phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene. Several LRTP indicators were investigated, including the Arctic contamination potential, meridional spreading, and zonal and meridional fluxes to remote regions.

  4. Black carbon and polycyclic aromatic hydrocarbon emissions from vehicles in the United States-Mexico border region: pilot study.

    Science.gov (United States)

    Kelly, Kerry; Wagner, David; Lighty, JoAnn; Quintero Núñez, Margarito; Vazquez, F Adrian; Collins, Kimberly; Barud-Zubillaga, Alberto

    2006-03-01

    The investigators developed a system to measure black carbon (BC) and particle-bound polycyclic aromatic hydrocarbon (PAH) emission factors during roadside sampling in four cities along the United States-Mexico border, Calexico/Mexicali and El Paso/Juarez. The measurement system included a photoacoustic analyzer for BC, a photoelectric aerosol sensor for particle-bound PAHs, and a carbon dioxide (CO2) analyzer. When a vehicle with measurable emissions passed the system probe, corresponding BC, PAH, and CO2 peaks were evident, and a fuel-based emission factor was estimated. A picture of each vehicle was also recorded with a digital camera. The advantage of this system, compared with other roadside methods, is the direct measurement of particulate matter components and limited interference from roadside dust. The study revealed some interesting trends: Mexican buses and all medium-duty trucks were more frequently identified as high emitters of BC and PAH than heavy-duty trucks or passenger vehicles. In addition, because of the high daily mileage of buses, they are good candidates for additional study. Mexican trucks and buses had higher average emission factors compared with U.S. trucks and buses, but the differences were not statistically significant. Few passenger vehicles had measurable BC and PAH emissions, although the highest emission factor came from an older model passenger vehicle licensed in Baja California.

  5. Comparative study of polycyclic aromatic hydrocarbons in coral tissues and the ambient sediments from Kenting National Park, Taiwan

    International Nuclear Information System (INIS)

    Ko, Fung-Chi; Chang, Chiung-Wen; Cheng, Jing-O.

    2014-01-01

    Surface sediments and corals (Acropora sp. and Montipora sp.) from the coastline of Kenting were analyzed in 2009 and 2010 for content levels of polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry. The total PAH concentrations (t-PAH) in corasls (143–1715 ng g −1 dw) were significantly higher than in the ambient sediments (2–59 ng g −1 dw) indicating the bioaccumulation of PAHs in corals. The spatial and seasonal variation in PAH levels suggested that land-loaded contaminants may be the main source of PAHs in the Kenting coral reefs. Based on molecular indices, PAHs were substantially of petroleum origin. The major PAH components were phenanthrene, pyrene and fluorine, but PAH congeners in corals and sediments still have characteristic composition patterns which would be altered by the bio/accumulation mechanisms. Further study is essential to assess and understand the impacts of these chemicals on coral reefs. Highlights: • PAH concentrations in Kenting coral reefs ranked minor in the worldwide comparison. • Isomeric ratios of PAHs suggested an important contribution of petrogenic sources. • PAHs have characteristic composition patterns which would be altered by the bio/accumulation mechanisms. • Higher levels of PAHs were found in coral tissues than in sediments (bioaccumulation). • Coral body burdens of PAHs were significantly correlated to adjacent sediments only at the areas with higher levels of PAHs. -- PAH levels in coral tissues were higher than in adjacent sediments (bioaccumulation)

  6. Study on the occurrence of polycyclic aromatic hydrocarbons in milk and meat/fish based baby food available in Italy.

    Science.gov (United States)

    Santonicola, Serena; Albrizio, Stefania; Murru, Nicoletta; Ferrante, Maria Carmela; Mercogliano, Raffaelina

    2017-10-01

    The study compared the profile of 14 polycyclic aromatic hydrocarbons, frequently occurred in food, in milk (N = 22) and meat/fish based (N = 18) baby foods available on the Italian market. PAH total levels, markers (Regulation EC/835/2011) and carcinogenic PAHs were determined by high- performance liquid chromatography with fluorescence detector (HPLC-FD). The average of total PAHs was 52.25 μg kg -1 in milk and 11.82 μg kg -1 in meat/fish based baby foods. The levels of PAH markers were higher than the permissible EU limits of 1 μg kg -1 in 18.2% and 77.7% milk, and 5.6% and 44.4% meat/fish based baby foods. Milk based samples showed significant higher values (P carcinogenic and possible carcinogenic hydrocarbons than meat/fish based products. The Margins of Exposure (MOE) value of milk based baby food samples indicated a potential concern for consumer health. Monitoring programs, and good agriculture and manufacture practices should be recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Long-term study of liver damage following subcutaneous injection of airborne particle extracts and polycyclic aromatic hydrocarbon fractions

    Energy Technology Data Exchange (ETDEWEB)

    Meiss, R.; Heinrich, U.; Offermann, M.; Themann, H.

    1982-02-01

    Female NMRI mice aged 9-12 weeks were each given a single subcutaneous injection of 0.5 ml of a suspension containing either the total extracts or the polycyclic aromatic hydrocarbon (PAH) fraction of airborne particles. Both the total extracts and PAH fractions contain 3 microgram benzopyrene. After about 15 months the livers were removed from the animals, which had by that time developed tumors at the injection site, and were subjected to electron-microscopical study. The essential alterations were observed in the nucleoli and the cell nuclei, which had greatly proliferated and exhibited irregular nuclear membranes. Advanced fibrosis was observed in central liver specimens of all groups. Marked alterations were also observed in the mitochondria and the mitochondrial cristae as well as in the bile canaliculi, Intracytoplasmic glycogen usually occurred densely clustered along the periphery of the cell. It may be concluded from the observations that both the total extract of atmospheric suspended particulate matter and the PAH fraction cause hematogenic damage to the liver following subcutaneous injection, a finding which cannot be interpreted as metastatic carcinoma.

  8. Long-term study of liver damage following subcutaneous injection of airborne particle extracts and polycyclic aromatic hydrocarbon fractions

    Energy Technology Data Exchange (ETDEWEB)

    Meiss, R.; Heinrich, U.; Offermann, M.; Themann, H.

    1982-02-01

    Female NMRI mice aged 9-12 weeks were each given a single subcutaneous injection of 0.5 ml of a suspension containing either the total extracts or the polycyclic aromatic hydrocarbon (PAH) fraction of airborne particles. Both the total extracts and PAH fractions contain 3 ..mu..g benzopyrene. After about 15 months the livers were removed from the animals, which had by that time developed tumors at the injection site, and were subjected to electron-microscopical study. The essential alterations were observed in the nucleoli and the cell nuclei, which had greatly proliferated and exhibited irregular nuclear membranes. Advanced fibrosis was observed in central liver specimens of all groups. Marked alterations were also observed in the mitochondria and the mitochondrial cristae as well as in the bile canaliculi. Intracytoplasmic glycogen usually occurred densely clustered along the periphery of the cell. It may be concluded from the observations that both the total extract of atmospheric suspended particulate matter and the PAH fraction cause hematogenic damage to the liver following subcutaneous injection, a finding which cannot be interpreted as metastatic carcinoma.

  9. Equilibrium passive sampling as a tool to study polycyclic aromatic hydrocarbons in Baltic Sea sediment pore-water systems

    DEFF Research Database (Denmark)

    Lang, Susann-Cathrin; Hursthouse, Andrew; Mayer, Philipp

    2015-01-01

    Solid Phase Microextraction (SPME) was applied to provide the first large scale dataset of freely dissolved concentrations for 9 polycyclic aromatic hydrocarbons (PAHs) in Baltic Sea sediment cores. Polydimethylsiloxane (PDMS) coated glass fibers were used for ex-situ equilibrium sampling followed...

  10. Polycyclic aromatic hydrocarbon-DNA adducts in cervix of women infected with carcinogenic human papillomavirus types: An immunohistochemistry study

    International Nuclear Information System (INIS)

    Pratt, M. Margaret; Sirajuddin, Paul; Poirier, Miriam C.; Schiffman, Mark; Glass, Andrew G.; Scott, David R.; Rush, Brenda B.; Olivero, Ofelia A.; Castle, Philip E.

    2007-01-01

    Among women infected with carcinogenic human papillomavirus (HPV), there is a two- to five-fold increased risk of cervical precancer and cancer in women who smoke compared to those who do not smoke. Because tobacco smoke contains carcinogenic polycyclic aromatic hydrocarbons (PAHs), it was of interest to examine human cervical tissue for PAH-DNA adduct formation. Here, we measured PAH-DNA adduct formation in cervical biopsies collected in follow-up among women who tested positive for carcinogenic HPV at baseline. A semi-quantitative immunohistochemistry (IHC) method using antiserum elicited against DNA modified with r7,t8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE) was used to measure nuclear PAH-DNA adduct formation. Cultured human cervical keratinocytes exposed to 0, 0.153, or 0.331 μM BPDE showed dose-dependent increases in r7,t8,t9-trihydroxy-c-10-(N 2 deoxyguanosyl)-7,8,9, 10-tetrahydro-benzo[a]pyrene (BPdG) adducts. For BPdG adduct analysis, paraffin-embedded keratinocytes were stained by IHC with analysis of nuclear color intensity by Automated Cellular Imaging System (ACIS) and, in parallel cultures, extracted DNA was assayed by quantitative BPDE-DNA chemiluminescence immunoassay (CIA). For paraffin-embedded samples from carcinogenic HPV-infected women, normal-appearing cervical squamous epithelium suitable for scoring was found in samples from 75 of the 114 individuals, including 29 cases of cervical precancer or cancer and 46 controls. With a lower limit of detection of 20 adducts/10 8 nucleotides, detectable PAH-DNA adduct values ranged from 25 to 191/10 8 nucleotides, with a median of 75/10 8 nucleotides. PAH-DNA adduct values above 150/10 8 nucleotides were found in eight samples, and in three samples adducts were non-detectable. There was no correlation between PAH-DNA adduct formation and either smoking or case status. Therefore, PAH-DNA adduct formation as measured by this methodology did not appear related to the increased risk

  11. Studies of Polycyclic Aromatic Hydrocarbons in Cigarette Mainstream Smoke: Identification, Tobacco Precursors, Control of Levels: A Review

    Directory of Open Access Journals (Sweden)

    Rodgman A

    2014-12-01

    Full Text Available During the period of tobacco smoke research from the early 1950s to the mid-1960s it was repeatedly asserted that a tobacco and many tobacco components were involved in the pyrogenesis of polycyclic aromatic hydrocarbons (PAHs, several of which were reported to initiate tumors on the skin of laboratory animals and b tobacco additives (flavorants, casing materials, humectants were highly likely to be similarly involved in PAH pyrogenesis. Extensive knowledge on PAHs was deemed highly necessary because of their claimed importance in the smoking-health issue. The numerous assertions about the generation of PAHs in cigarette mainstream smoke (MSS triggered extensive and intensive research both within and outside the Tobacco Industry to define the nature of the PAHs, their per cigarette MSS delivery amounts, their precursors, etc. It was not until 1960 that VAN DUUREN et al. (1 reported three specific aza-arenes in cigarette MSS that were asserted to be involved in smokers’ respiratory tract cancer. As noted in a recent Letter to the Editors (2, the presence of these three aza-arenes in tobacco smoke has never been confirmed. Between 1960 and 1965, other MSS components (phenols as promoters, polonium-210, N-nitrosamines, ciliastatic compounds were asserted to be responsible for smoking related diseases. However, no major assertions were made that phenols, polonium-210, or the N-nitrosamines were derived from flavorants, casing materials, or humectants. Some investigators did report that several ciliastats were derived from added sugars and glycerol. The ciliastat proposal was drastically diminished in importance by the findings in the 1960s that only a relatively small proportion of the ciliastats reached the smoker's cilia. During that time, pertinent skills and competencies in research on tobacco smoke composition, particularly the PAH fraction, have been developed. Such skills permitted the isolation in crystalline form of 14 PAHs and the

  12. Polycyclic aromatic hydrocarbon-DNA adducts in cervix of women infected with carcinogenic human papillomavirus types: An immunohistochemistry study

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, M. Margaret [Carcinogen-DNA Interactions Section, LCBG, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD (United States)], E-mail: prattm@mail.nih.gov; Sirajuddin, Paul; Poirier, Miriam C. [Carcinogen-DNA Interactions Section, LCBG, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD (United States); Schiffman, Mark [Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, MD (United States); Glass, Andrew G.; Scott, David R.; Rush, Brenda B. [Northwest Kaiser Permanente, Portland, OR (United States); Olivero, Ofelia A. [Carcinogen-DNA Interactions Section, LCBG, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD (United States); Castle, Philip E. [Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, MD (United States)

    2007-11-01

    Among women infected with carcinogenic human papillomavirus (HPV), there is a two- to five-fold increased risk of cervical precancer and cancer in women who smoke compared to those who do not smoke. Because tobacco smoke contains carcinogenic polycyclic aromatic hydrocarbons (PAHs), it was of interest to examine human cervical tissue for PAH-DNA adduct formation. Here, we measured PAH-DNA adduct formation in cervical biopsies collected in follow-up among women who tested positive for carcinogenic HPV at baseline. A semi-quantitative immunohistochemistry (IHC) method using antiserum elicited against DNA modified with r7,t8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE) was used to measure nuclear PAH-DNA adduct formation. Cultured human cervical keratinocytes exposed to 0, 0.153, or 0.331 {mu}M BPDE showed dose-dependent increases in r7,t8,t9-trihydroxy-c-10-(N{sup 2}deoxyguanosyl)-7,8,9, 10-tetrahydro-benzo[a]pyrene (BPdG) adducts. For BPdG adduct analysis, paraffin-embedded keratinocytes were stained by IHC with analysis of nuclear color intensity by Automated Cellular Imaging System (ACIS) and, in parallel cultures, extracted DNA was assayed by quantitative BPDE-DNA chemiluminescence immunoassay (CIA). For paraffin-embedded samples from carcinogenic HPV-infected women, normal-appearing cervical squamous epithelium suitable for scoring was found in samples from 75 of the 114 individuals, including 29 cases of cervical precancer or cancer and 46 controls. With a lower limit of detection of 20 adducts/10{sup 8} nucleotides, detectable PAH-DNA adduct values ranged from 25 to 191/10{sup 8} nucleotides, with a median of 75/10{sup 8} nucleotides. PAH-DNA adduct values above 150/10{sup 8} nucleotides were found in eight samples, and in three samples adducts were non-detectable. There was no correlation between PAH-DNA adduct formation and either smoking or case status. Therefore, PAH-DNA adduct formation as measured by this methodology did not appear

  13. Electronic and optical properties of families of polycyclic aromatic hydrocarbons: A systematic (time-dependent) density functional theory study

    International Nuclear Information System (INIS)

    Malloci, G.; Cappellini, G.; Mulas, G.; Mattoni, A.

    2011-01-01

    Graphical abstract: Electronic absorption spectra of the neutral molecules of the four PAH classes considered, as computed using the real-time real-space TD-DFT. Highlights: →We present a systematic comparative study of families of PAHs. → We computed electronic, optical, and transport properties as a function of size. → We considered oligoacenes, phenacenes, circumacenes, and oligorylenes. → Circumacenes have the best transport properties compared to the other classes. → Oligorylenes are much more efficient in absorbing low-energy photons. - Abstract: Homologous classes of polycyclic aromatic hydrocarbons (PAHs) in their crystalline state are among the most promising materials for organic opto-electronics. Following previous works on oligoacenes we present a systematic comparative study of the electronic, optical, and transport properties of oligoacenes, phenacenes, circumacenes, and oligorylenes. Using density functional theory (DFT) and time-dependent DFT we computed: (i) electron affinities and first ionization energies; (ii) quasiparticle correction to the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap; (iii) molecular reorganization energies and (iv) electronic absorption spectra of neutral and ±1 charged systems. The excitonic effects are estimated by comparing the optical gap and the quasiparticle corrected HOMO-LUMO energy gap. For each molecular property computed, general trends as a function of molecular size and charge state are discussed. Overall, we find that circumacenes have the best transport properties, displaying a steeper decrease of the molecular reorganization energy at increasing sizes, while oligorylenes are much more efficient in absorbing low-energy photons in comparison to the other classes.

  14. Polycyclic aromatic hydrocarbons exposure decreased sperm mitochondrial DNA copy number: A cross-sectional study (MARHCS) in Chongqing, China.

    Science.gov (United States)

    Ling, Xi; Zhang, Guowei; Sun, Lei; Wang, Zhi; Zou, Peng; Gao, Jianfang; Peng, Kaige; Chen, Qing; Yang, Huan; Zhou, Niya; Cui, Zhihong; Zhou, Ziyuan; Liu, Jinyi; Cao, Jia; Ao, Lin

    2017-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants that have adverse effects on the male reproductive function. Many studies have confirmed that PAHs preferentially accumulate in mitochondria DNA relative to nuclear DNA and disrupt mitochondrial functions. However, it is rare whether exposure to PAHs is associated with mitochondrial damage and dysfunction in sperm. To evaluate the effects of PAHs on sperm mitochondria, we measured mitochondrial membrane potential (MMP), mitochondrial DNA copy number (mtDNAcn) and mtDNA integrity in 666 individuals from the Male Reproductive Health in Chongqing College Students (MARHCS) study. PAHs exposure was estimated by measuring eight urinary PAH metabolites (1-OHNap, 2-OHNap, 1-OHPhe, 2-OHPhe, 3-OHPhe, 4-OHPhe, 2-OHFlu and 1-OHPyr). The subjects were divided into low, median and high exposure groups using the tertile levels of urinary PAH metabolites. In univariate analyses, the results showed that increased levels of 2-OHPhe, 3-OHPhe, ∑Phe metabolites and 2-OHFlu were found to be associated with decreased sperm mtDNAcn. After adjusting for potential confounders, significantly negative associations of these metabolites remained (p = 0.039, 0.012, 0.01, 0.035, respectively). Each 1 μg/g creatinine increase in 2-OHPhe, 3-OHPhe, ∑Phe metabolites and 2-OHFlu was associated with a decrease in sperm mtDNAcn of 9.427%, 11.488%, 9.635% and 11.692%, respectively. There were no significant associations between urinary PAH metabolites and sperm MMP or mtDNA integrity. The results indicated that the low exposure levels of PAHs can cause abnormities in sperm mitochondria. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. 451 Case studies Cardiac

    African Journals Online (AJOL)

    Marinda

    Case Studies. 29 ... A case of a 26-year-old ASA I physical status male undergoing septoplasty had an abrupt ... myocardial infarction, severe hypertensive crisis, cerebral .... or no formal management is required in an ASA I patient.8 One.

  16. Polycyclic aromatic hydrocarbons and their derivatives in indoor and outdoor air in an eight-home study

    Science.gov (United States)

    Chuang, Jane C.; Mack, Gregory A.; Kuhlman, Michael R.; Wilson, Nancy K.

    A pilot field study was performed in Columbus, OH, during the winter of 1986/1987. The objectives were to determine the feasibility of the use of a newly developed quiet sampler in indoor air sampling for particles and semivolatile organic compounds (SVOC) and to measure the concentrations of polycyclic aromatic hydrocarbons (PAH), PAH derivatives, and nicotine in air in selected residences. Eight homes were chosen for sampling on the basis of these characteristics: electric/gas heating system, electric/gas cooking appliances, and the absence/presence of environmental tobacco smoke (ETS). The indoor sampler was equipped with a quartz-fiber filter to collect particles followed by XAD-4 resin to trap SVOC. A PS-1 sampler with a similar sampling module was used outdoors. The indoor air was sampled in the kitchen and living room areas over two consecutive 8-h periods. The outdoor air was sampled concurrently with the indoor samples over a 16-h period. Fifteen PAH, five nitro-PAH, five oxygenated PAH, and three nitrogen heterocyclic compounds were determined in these samples. The most abundant PAH found indoors was naphthalene. The indoor concentrations of PAH derivatives were lower than those of their parent compounds. Average concentrations of all but three target compounds (naphthalene dicarboxylic acid anhydride, pyrene dicarboxylic acid anhydride, and 2-nitrofluoranthene) were higher indoors than outdoors. Environmental tobacco smoke was the most significant influence on indoor pollutant levels. Homes with gas heating systems had higher indoor pollutant levels than homes with electric heating systems. However, the true effects of heating and cooking systems were not characterized as accurately as the effects of ETS because of the small sample sizes and the lack of statistical significance for most pollutant differences in the absence of ETS. The concentrations of PAH marker compounds (phenanthrene, fluoranthene, and pyrene) correlated well with the concentrations

  17. Urinary polycyclic aromatic hydrocarbons as a biomarker of exposure to PAHs in air: a pilot study among pregnant women.

    Science.gov (United States)

    Nethery, Elizabeth; Wheeler, Amanda J; Fisher, Mandy; Sjödin, Andreas; Li, Zheng; Romanoff, Lovisa C; Foster, Warren; Arbuckle, Tye E

    2012-01-01

    Recent studies have linked increased polycyclic aromatic hydrocarbons (PAHs) in air and adverse fetal health outcomes. Urinary PAH metabolites are of interest for exposure assessment if they can predict PAHs in air. We investigated exposure to PAHs by collecting air and urine samples among pregnant women pre-selected as living in "high" (downtown and close to steel mills, n=9) and "low" (suburban, n=10) exposure areas. We analyzed first-morning urine voids from all 3 trimesters of pregnancy for urinary PAH metabolites and compared these to personal air PAH/PM(2.5)/NO(2)/NO(X) samples collected in the 3rd trimester. We also evaluated activities and home characteristics, geographic indicators and outdoor central site PM(2.5)/NO(2)/NO(X) (all trimesters). Personal air exposures to the lighter molecular weight (MW) PAHs were linked to indoor sources (candles and incense), whereas the heavier PAHs were related to outdoor sources. Geometric means of all personal air measurements were higher in the "high" exposure group. We suggest that centrally monitored heavier MW PAHs could be used to predict personal exposures for heavier PAHs only. Urine metabolites were only directly correlated with their parent air PAHs for phenanthrene (Pearson's r=0.31-0.45) and fluorene (r=0.37-0.58). Predictive models suggest that specific metabolites (3-hydroyxyfluorene and 3-hydroxyphenanthrene) may be related to their parent air PAH exposures. The metabolite 2-hydroxynaphthalene was linked to smoking and the metabolite 1-hydroxypyrene was linked to dietary exposures. For researchers interested in predicting exposure to airborne lighter MW PAHs using urinary PAH metabolites, we propose that hydroxyfluorene and hydroxyphenanthrene metabolites be considered.

  18. [Case and studies].

    Science.gov (United States)

    Schubert, András

    2015-11-15

    Case studies and case reports form an important and ever growing part of scientific and scholarly literature. The paper deals with the share and citation rate of these publication types on different fields of research. In general, evidence seems to support the opinion that an excessive number of such publications may negatively influence the impact factor of the journal. In the literature of scientometrics, case studies (at least the presence of the term "case study" in the titles of the papers) have a moderate share, but their citation rate is practically equal to that of other publication types.

  19. Geostatistical characterization of soil pollution at industrial sites Case of polycyclic aromatic hydrocarbons at former coking plants; Caracterisation geostatistique de pollutions industrielles de sols cas des hydrocarbures aromatiques polycycliques sur d'anciens sites de cokeries

    Energy Technology Data Exchange (ETDEWEB)

    Jeannee, N

    2001-05-15

    Estimating polycyclic aromatic hydrocarbons concentrations in soil at former industrial sites poses several practical problems on account of the properties of the contaminants and the history of site: 1)collection and preparation of samples from highly heterogeneous material, 2) high short scale variability, particularly in presence of backfill, 3) highly contrasted grades making the vario-gram inference complicated. The sampling strategy generally adopted for contaminated sites is based on the historical information. Systematic sampling recommended for geostatistical estimation is often considered to be excessive and unnecessary. Two former coking plants are used as test cases for comparing several geostatistical methods for estimating (i) in situ concentrations and (ii) the probability that they are above a pollution threshold. Several practical and methodological questions are considered: 1) the properties of various estimators of the experimental vario-gram and the validity of the results; 2) the use of soft data, such as historical information, organoleptic observations and semi-quantitative methods, with a view to improve the precision of the estimates; 3) the comparison of standard sampling strategies, taking into account vertical repartition of grades and the history of the site. Multiple analyses of the same sample give an approximation of the sampling error. Short scale sampling shows the difficulty of selecting soils in the absence of a spatial structure. Sensitivity studies are carried out to assess how densely sampled soft data can improve estimates. By using mainly existing models, this work aims at giving practical recommendations for the characterization of soil pollution. (author)

  20. Geostatistical characterization of soil pollution at industrial sites Case of polycyclic aromatic hydrocarbons at former coking plants; Caracterisation geostatistique de pollutions industrielles de sols cas des hydrocarbures aromatiques polycycliques sur d'anciens sites de cokeries

    Energy Technology Data Exchange (ETDEWEB)

    Jeannee, N.

    2001-05-15

    Estimating polycyclic aromatic hydrocarbons concentrations in soil at former industrial sites poses several practical problems on account of the properties of the contaminants and the history of site: 1)collection and preparation of samples from highly heterogeneous material, 2) high short scale variability, particularly in presence of backfill, 3) highly contrasted grades making the vario-gram inference complicated. The sampling strategy generally adopted for contaminated sites is based on the historical information. Systematic sampling recommended for geostatistical estimation is often considered to be excessive and unnecessary. Two former coking plants are used as test cases for comparing several geostatistical methods for estimating (i) in situ concentrations and (ii) the probability that they are above a pollution threshold. Several practical and methodological questions are considered: 1) the properties of various estimators of the experimental vario-gram and the validity of the results; 2) the use of soft data, such as historical information, organoleptic observations and semi-quantitative methods, with a view to improve the precision of the estimates; 3) the comparison of standard sampling strategies, taking into account vertical repartition of grades and the history of the site. Multiple analyses of the same sample give an approximation of the sampling error. Short scale sampling shows the difficulty of selecting soils in the absence of a spatial structure. Sensitivity studies are carried out to assess how densely sampled soft data can improve estimates. By using mainly existing models, this work aims at giving practical recommendations for the characterization of soil pollution. (author)

  1. Septic Systems Case Studies

    Science.gov (United States)

    A collection of septic systems case studies to help community planners, elected officials, health department staff, state officials, and interested citizens explore alternatives for managing their decentralized wastewater treatment systems.

  2. HYDROGEOLOGIC CASE STUDIES

    Science.gov (United States)

    Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

  3. A Psychobiographical Case Study

    African Journals Online (AJOL)

    man, and cancer fighter. This psychobiographical case study entailed a psychosocial-historical ... does not draw more attention as a research method, as this approach has .... of the applied Levinsonian theory to the life of Jobs against the ...

  4. Qualitative Case Study Guidelines

    Science.gov (United States)

    2013-11-01

    Introduction to Sociological Methods. 2nd ed. New York, McGraw-Hill 14. Denzin , N. K. and Lincoln , Y. S. (2011) The SAGE Handbook of Qualitative...The Art of Science. In: Denzin , N. K. and Lincoln , Y. S. (eds.) Handbook of Qualitative Research. Thousand Oaks, Sage 19. GAO (1990) Case Study...Rinehart & Winston 39. Stake, R. E. (1994) Case Studies. In: Denzin , N. K. and Lincoln , Y. S. (eds.) Handbook of Qualitative Research. Thousand Oaks, Sage

  5. Polycyclic Aromatic Hydrocarbons

    Science.gov (United States)

    Salama, Farid

    2010-01-01

    Carbonaceous materials play an important role in space. Polycyclic Aromatic Hydrocarbons (PAHs) are a ubiquitous component of the carbonaceous materials. PAHs are the best-known candidates to account for the IR emission bands. They are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge is to reproduce in the laboratory the physical conditions that exist in the emission and absorption interstellar zones. The harsh physical conditions of the ISM -low temperature, collisionless, strong UV radiation fields- are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions and radicals are formed from the neutral precursors in an isolated environment at low temperature and probed with high-sensitivity cavity ringdown spectroscopy in the NUV-NIR range. Carbon nanoparticles are also formed during the short residence time of the precursors in the plasma and are characterized with time-offlight mass spectrometry. These experiments provide unique information on the spectra of large carbonaceous molecules and ions in the gas phase that can now be directly compared to interstellar and circumstellar observations (IR emission bands, DIBs, extinction curve). These findings also hold great potential for understanding the formation process of interstellar carbonaceous grains. We will review recent progress in the experimental and theoretical studies of PAHs, compare the laboratory data with astronomical observations and discuss the global implications.

  6. A comparative study on fluorescence quenching of CdTe nanocrystals with a serial of polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Baslak, Canan, E-mail: cananbaslak@gmail.com [Advanced Technology Research and Application Center, Selcuk University, 42075 Konya (Turkey); Department of Chemistry, Faculty of Science, Selcuk University, 42075 Konya (Turkey); Kus, Mahmut, E-mail: mahmutkus1@gmail.com [Advanced Technology Research and Application Center, Selcuk University, 42075 Konya (Turkey); Department of Chemical Engineering, Faculty of Engineering, Selcuk University, 42075 Konya (Turkey); Cengeloglu, Yunus [Department of Chemistry, Faculty of Science, Selcuk University, 42075 Konya (Turkey); Ersoz, Mustafa [Advanced Technology Research and Application Center, Selcuk University, 42075 Konya (Turkey); Department of Chemistry, Faculty of Science, Selcuk University, 42075 Konya (Turkey)

    2014-09-15

    We report sensing different polycyclic aromatic hydrocarbons (PAHs) with colloidal CdTe nanocrystals. The effect of molecular structure on quenching rate for 2-hyroxy-1-naphthaldehyde (2H–1N), 9,10-phenanthraquinone (PQ), 9-anthracenecarboxaldehyde (9-AC) and quinoline (Q) is presented. The quenching rate constants are observed to be strongly dependent on the molecular structure. PQ, consisting of two carbonyl groups, shows the highest rate constant while Q shows the worst one. Both static and dynamic quenching are simultaneously observed for PQ and 2H–1N. Therefore extended Stern–Volmer equations are used to calculate rate constants. Results showed that dynamic quenching is a dominant process. The rate constants for PQ, 2H–1N, 9-AC and Q are calculated to be 64.84, 10.73, 10.66 and 1.85 respectively. - Highlights: • We report the fluorescence quenching of colloidal CdTe nanocrystals with different polycyclic aromatic hydrocarbons. • The quenching rate constants are observed to be strongly dependent on the molecular structure. • Static and dynamic quenching are simultaneously observed. • The best quenching was observed for 9,10-phenanthraquinone.

  7. Remediation of soil contaminated with polycyclic aromatic ...

    African Journals Online (AJOL)

    user

    2011-02-14

    Feb 14, 2011 ... The aim of this study was to determine ways of remediating soils contaminated with polycyclic aromatic hydrocarbons (PAHs) associated with crude oil. The study involves the use of planted cowpeas, mushrooms, algae, dead vegetable and live earthworm, and fire-heating of the contaminated garden soil ...

  8. Objectivist case study research

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner; Fachner, Jörg

    2016-01-01

    be achieved through the use of objectivist case study research. The strength of the case study design is that it allows for uncovering or suggesting causal relationships in real-life settings through an intensive and rich collection of data. According to Hilliard (1993), the opposite applies for extensive......In order to comprehend the impact of music therapy or music therapy processes, a researcher might look for an approach where the topic under investigation can be understood within a broader context. This calls for a rich inclusion of data and consequently a limited number of participants and may...... designs, in which a small amount of data is gathered on a large number of subjects. With the richness of data, the intensive design is ―the primary pragmatic reason for engaging in single-case or small N research‖ (p. 374) and for working from an idiographic rather than a nomothetic perspective....

  9. Bioremediation of Polycyclic Aromatic Hydrocarbon contaminated ...

    African Journals Online (AJOL)

    This study investigates the effect of lead and chromium on the rate of bioremediation of polycyclic aromatic hydrocarbon (PAH) contaminated clay soil. Naphthalene was used as a target PAH. The soil was sterilized by heating at 120oC for one hour. 100g of the soil was contaminated with lead, chromium, nickel and mercury ...

  10. Case Studies - Cervical Cancer

    Centers for Disease Control (CDC) Podcasts

    Dr. Alan Waxman, a professor of obstetrics and gynecology at the University of New Mexico and chair of the American College of Obstetricians and Gynecologists (ACOG) committee for the underserved, talks about several case studies for cervical cancer screening and management.

  11. Nuclear forensics case studies

    International Nuclear Information System (INIS)

    Fedchenko, Vitaly

    2016-01-01

    The objective of this presentation is to share three case studies from the Institute of Transuranium Elements (ITU) which describe the application of nuclear forensics to events where nuclear and other radioactive material was found to be out of regulatory control

  12. SCA12 case study

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 88; Issue 1. Utilizing linkage disequilibrium information from Indian Genome Variation Database for mapping mutations: SCA12 case study. Samira Bahl Ikhlak Ahmed The Indian Genome Variation Consortium Mitali Mukerji. Research Article Volume 88 Issue 1 April 2009 pp 55- ...

  13. national Case study

    African Journals Online (AJOL)

    This national case study reports on the development of a national network, ... system under the new policy), tends to be limited by content on problems and ... 20 credit programme; and within two Post Graduate Certificate of Education contexts, ...... descriptive with an issues focus (empirical) towards awareness production to.

  14. MRI case studies

    International Nuclear Information System (INIS)

    Huggett, S.; Barber, J.

    1989-01-01

    Three case studies are presented to show the value of magnetic resonance imaging used in conjunction with other imaging techniques. In each case MRI proved a vital diagnostic tool and superior to CT in showing firstly the haematoma in a patient with aphasia and right-sided weakness, secondly the size of the disc herniation in a patient with severe leg and ankle pains and thirdly the existence of a metastatic lesion in a patient with a previous history of breast cancer. 11 figs

  15. Study of polycyclic aromatic hydrocarbon contamination of major rivers in the Czech Republic using biliary metabolite in chub, Leuciscus cephalus L.

    Science.gov (United States)

    Blahova, Jana; Leontovycova, Drahomira; Kodes, Vit; Svobodova, Zdenka

    2013-05-01

    The aim of the present study was to evaluate polycyclic aromatic hydrocarbon (PAH) contamination of the major rivers in the Czech Republic using 1-hydroxypyrene (1-OHP) content in chub bile as a biomarker. The highest concentration of 1-OHP was found in the Otava River at Topělec (80.5 ng mg protein(-1)); the lowest content of 1-OHP was found in the Vltava at Zelčín (9.6 ng mg protein(-1)). At all sites, bottom sediment samples were collected and analyzed for PAH content. The PAH content ranged between 1.2 and 15.2 mg kg dry mass(-1) at all sites. Statistically significant positive correlations (p < 0.05) between biliary 1-OHP and sediment PAH content were found. Correlation coefficients for total and individual priority PAHs ranged from 0.63 to 0.77.

  16. Effects of polycyclic aromatic hydrocarbons (PAHs) in environmental pollution on exogenous and oxidative DNA damage (EXPAH project): description of the population under study.

    Science.gov (United States)

    Taioli, Emanuela; Sram, Radim J; Garte, Seymour; Kalina, Ivan; Popov, Todor A; Farmer, Peter B

    2007-07-01

    The EXPAH project was a molecular epidemiology study whose aims were to evaluate the hypothesis that polycyclic aromatic hydrocarbons (PAHs) are a major source of genotoxic activities of organic mixtures associated with air pollution. Biomarkers of exposure, effects and susceptibility, and oxidative DNA damage were measured in three PAH-exposed populations from Prague (Czech Republic), Kosice (Slovakia) and Sofia (Bulgaria). Control populations were included from each city. In total 356 individuals were enrolled. A questionnaire was used to determine life style/dietary factors. Ambient air exposure was measured by stationary monitoring, and personal exposure monitoring was also carried out. The characteristics of the population are described in this paper together with their personal exposure to carcinogenic PAHs (c-PAHs). The dose of c-PAH exposure was found to vary between the occupationally exposed (e.g. policemen and bus drivers) and the control populations in each country, and also varied from country to country.

  17. Case study - Czechoslovakia

    International Nuclear Information System (INIS)

    Kovar, P.

    1986-01-01

    In the lecture Case Study - Czechoslovakia with the sub-title 'Unified System of Personnel Preparation for Nuclear Programme in Czechoslovakia' the actual status and the current experience of NPP personnel training and preparation in Czechoslovakia are introduced. The above mentioned training system is presented and demonstrated by the story of a proxy person who is going to become shift engineer in a nuclear power plant in Czechoslovakia. (orig./HP)

  18. Case Studies - Cervical Cancer

    Centers for Disease Control (CDC) Podcasts

    2010-10-15

    Dr. Alan Waxman, a professor of obstetrics and gynecology at the University of New Mexico and chair of the American College of Obstetricians and Gynecologists (ACOG) committee for the underserved, talks about several case studies for cervical cancer screening and management.  Created: 10/15/2010 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP), Division of Cancer Prevention and Control (DCPC).   Date Released: 6/9/2010.

  19. H2 EJECTION FROM POLYCYCLIC AROMATIC HYDROCARBONS: INFRARED MULTIPHOTON DISSOCIATION STUDY OF PROTONATED ACENAPHTHENE AND 9,10-DIHYDROPHENANTHRENE

    International Nuclear Information System (INIS)

    Szczepanski, Jan; Vala, Martin T.; Oomens, Jos; Steill, Jeffrey D.

    2011-01-01

    The infrared multiple-photon dissociation (IRMPD) spectra of protonated acenaphthene ([ACN+H] + ) and 9,10-dihydrophenanthrene ([DHP+H] + ) have been recorded using an infrared free electron laser after the compounds were protonated by electrospray ionization and trapped in a Fourier transform ion cyclotron mass spectrometer. In both compounds, the loss of two mass units is predominant. Density functional calculations (B3LYP/6-311++G(d,p)) of the infrared spectra of all possible protonated isomers of each species showed that the observed IRMPD spectra are best fit to the isomer with the largest proton affinity and lowest relative electronic energy. Potential energy surfaces of the most stable isomers of [ACN+H] + and [DHP+H] + have been calculated for H and H 2 loss. The lowest energy barriers are for loss of H 2 , with predicted energies 4.28 and 4.15 eV, respectively. After H 2 ejection, the adjacent aliphatic hydrogens migrate to the bare ejection site and stabilize the remaining fragment. Single H loss may occur from [ACN+H] + but the energy required is higher. No single H loss is predicted from [DHP+H] + , only H migration around the carbon skeleton. The vibrational bands in the parent closed-shell protonated polycyclic aromatic hydrocarbons are compared to bands observed from the interstellar medium.

  20. Case Study - Alpha

    Directory of Open Access Journals (Sweden)

    Stephen Leybourne

    2016-11-01

    Full Text Available This case study was developed from an actual scenario by Dr. Steve Leybourne of Boston University.  The case documents the historical evolution of an organization, and has been used successfully in courses dealing with organizational and cultural change, and the utilization of ‘soft skills’ in project-based management. This is a short case, ideal for classroom use and discussion.  The issues are easily accessible to students, and there is a single wide ranging question that allows for the inclusion of many issues surrounding strategic decision-making, and behavioural and cultural change. Alpha was one of the earlier companies in the USA to invest in large, edge-of-town superstores, with plentiful free vehicle parking, selling food and related household products. Alpha was created in the 1950s as a subsidiary of a major publicly quoted retail group.  It started business by opening a string of very large discount stores in converted industrial and warehouse premises in the south of the United States. In the early days shoppers were offered a limited range of very competitively priced products. When Alpha went public in 1981 it was the fourth largest food retailer in the US, selling an ever-widening range of food and non-food products.  Its success continued to be based on high volume, low margins and good value for money, under the slogan of ‘Alpha Price.’

  1. NOx trade. Case studies

    International Nuclear Information System (INIS)

    Jantzen, J.

    2002-01-01

    Some of the questions with respect to the trade of nitrogen oxides that businesses in the Netherlands have to deal with are dealt with: should a business buy or sell rights for NOx emission; which measures must be taken to reduce NOx emission; how much must be invested; and how to deal with uncertainties with regard to prices. Simulations were carried out with the MOSES model to find the answers to those questions. Results of some case studies are presented, focusing on the chemical sector in the Netherlands. Finally, the financial (dis)advantages of NOx trade and the related uncertainties for a single enterprise are discussed [nl

  2. OBSESSIONS: CASE REPORT STUDY

    Directory of Open Access Journals (Sweden)

    Miloš Židanik

    2004-01-01

    Full Text Available Background. Obsessions are one of the most refractory psychiatric disorders. The therapeutic guidelines include a psychopharmacotherapy and the use of behavioural and supportive psychotherapy.Methods. This case report study presents a patient with a homicide obsessions at the forefront and narcissistic personality disorder in background. The use of analytical oriented psychotherapy, which helped to resolve axis-1 symptoms, is described.Conclusions. In the therapy of patients it is important to have the knowledge about the national therapeutic guidelines and critical distance toward them as well. Which therapy to use should be decided by the individual patient’s needs.

  3. Critical point measurement of some polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Nikitin, Eugene D.; Popov, Alexander P.

    2015-01-01

    Highlights: • Critical properties of five polycyclic aromatic hydrocarbons were measured. • These hydrocarbons decompose at near-critical temperatures. • Pulse-heating method with short residence times was used. - Abstract: The critical temperatures and the critical pressures of five polycyclic aromatic compounds, namely, acenaphthene, fluorene, anthracene, phenanthrene, and pyrene have been measured. All the compounds studied decompose at near-critical temperatures. A pulse-heating technique applicable to measuring the critical properties of thermally unstable compounds has been used. The times from the beginning of a heating pulse to the moment of reaching the critical temperature were from (0.06 to 0.85) ms. The short residence times provide little degradation of the substances in the course of the experiments. The experimental critical parameters of the polycyclic aromatic compounds have been compared with those estimated by five predictive methods. The acentric factors of polycyclic aromatic compounds studied have been calculated

  4. Bioassay of polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Van Kirk, E.A.

    1980-08-01

    A positive relationship was found between the photodynamic activity of 24 polycyclic aromatic hydrocarbons versus published results on the mutagenicity, carcinogenicity, and initiation of unscheduled DNA synthesis. Metabolic activation of benzo(a)pyrene resulted in detection of increased mutagenesis in Paramecium tetraurelia as found also in the Ames Salmonella assay. The utility of P. tetraurelia as a biological detector of hazardous polycyclic aromatic hydrocarbons is discussed.

  5. Goiania incident case study

    International Nuclear Information System (INIS)

    Petterson, J.S.

    1988-06-01

    The reasons for wanting to document this case study and present the findings are simple. According to USDOE technical risk assessments (and our own initial work on the Hanford socioeconomic study), the likelihood of a major accident involving exposure to radioactive materials in the process of site characterization, construction, operation, and closure of a high-level waste repository is extremely remote. Most would agree, however, that there is a relatively high probability that a minor accident involving radiological contamination will occur sometime during the lifetime of the repository -- for example, during transport, at an MRS site or at the permanent site itself during repacking and deposition. Thus, one of the major concerns of the Yucca Mountain Socioeconomic Study is the potential impact of a relatively minor radiation-related accident. A large number of potential impact of a relatively minor radiation-related accident. A large number of potential accident scenarios have been under consideration (such as a transportation or other surface accident which results in a significant decline in tourism, the number of conventions, or the selection of Nevada as a retirement residence). The results of the work in Goiania make it clear, however, that such a significant shift in established social patterns and trends is not likely to occur as a direct outcome of a single nuclear-related accident (even, perhaps, a relatively major one), but rather, are likely to occur as a result of the enduring social interpretations of such an accident -- that is, as a result of the process of understanding, communicating, and socially sustaining a particular set of associations with respect to the initial incident

  6. FMCT verification: Case studies

    International Nuclear Information System (INIS)

    Hui Zhang

    2001-01-01

    Full text: How to manage the trade-off between the need for transparency and the concern about the disclosure of sensitive information would be a key issue during the negotiations of FMCT verification provision. This paper will explore the general concerns on FMCT verification; and demonstrate what verification measures might be applied to those reprocessing and enrichment plants. A primary goal of an FMCT will be to have the five declared nuclear weapon states and the three that operate unsafeguarded nuclear facilities become parties. One focus in negotiating the FMCT will be verification. Appropriate verification measures should be applied in each case. Most importantly, FMCT verification would focus, in the first instance, on these states' fissile material production facilities. After the FMCT enters into force, all these facilities should be declared. Some would continue operating to produce civil nuclear power or to produce fissile material for non- explosive military uses. The verification measures necessary for these operating facilities would be essentially IAEA safeguards, as currently being applied to non-nuclear weapon states under the NPT. However, some production facilities would be declared and shut down. Thus, one important task of the FMCT verifications will be to confirm the status of these closed facilities. As case studies, this paper will focus on the verification of those shutdown facilities. The FMCT verification system for former military facilities would have to differ in some ways from traditional IAEA safeguards. For example, there could be concerns about the potential loss of sensitive information at these facilities or at collocated facilities. Eventually, some safeguards measures such as environmental sampling might be seen as too intrusive. Thus, effective but less intrusive verification measures may be needed. Some sensitive nuclear facilities would be subject for the first time to international inspections, which could raise concerns

  7. Polycyclic hydrocarbons - occurrence and determination

    International Nuclear Information System (INIS)

    Drzewicz, P.

    2007-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are a special group of atmospheric contaminants included in the persistent toxic substances (PTS) and also in the volatile organic compounds (VOC) groups. PAHs are present in the atmosphere and their origin can be due to anthropogenic activities. The main source of emission of PAH is the combustion of fossil fuels. Their specific characteristics, high volatility, mutagenic and carcinogenic power, easily transportable for long distances with the wind, make them important contaminants despite of the fact that they are present at very low concentrations. The report provides a review of main analytical methods applied in the determination of PAH in air. Special attention was devoted to heterocyclic PAH which contain one or more heteroatom (sulphur, oxygen, nitrogen) in the multiple-fused ring. The presence of heterocyclic PAH requires very complex, laborious and long lasting sample separation methods before analysis. In some cases, application of different temperature programs in gas chromatography allows to determine PAH and heterocyclic PAH in gaseous samples without sample pretreatment. Gas chromatography methods for the determination of PAH and heterocyclic PAH in the gas from combustion of light heating oil has been optimized. (author) [pl

  8. Final report on case studies

    DEFF Research Database (Denmark)

    Ljungberg, Daniel; McKelvey, Maureen; Lassen, Astrid Heidemann

    2012-01-01

    Case study as a research design means investigating a single or multiple instance(s) or setting(s) (i.e. a case) and its entire context to explain a phenomenon and its processes. This is achieved through detailed understanding, usually comprised of multiple sources of information. In this way, case...... studies attempt to provide as a complete an understanding of a (complex) phenomenon as possible. Within the AEGIS project, survey and case study research are complementary. They are complementary in the sense that the former can provide more generalizable evidence on a phenomenon in terms of cross......-sectional data, while the latter can provide more in-depth (qualitative) understanding on specific issues. In systematically examining the case studies, however, this report goes beyond a typical single case study. Here we provide a synthesis of 86 case studies. Multiple case studies, following similar focus...

  9. Antihistamine medication may alleviate negative effects of prenatal exposure to polycyclic aromatic hydrocarbons (PAH) on lung function in children. Birth cohort prospective study.

    Science.gov (United States)

    Jedrychowski, Wieslaw A; Perera, Frederica P; Maugeri, Umberto; Majewska, Renata; Spengler, Jack; Mroz, Elzbieta; Flak, Elzbieta; Klimaszewska-Rembiasz, Maria; Camman, David

    2015-05-01

    The main purpose of the present study was to test the hypothesis that the depressed lung growth attributable to prenatal exposure to polycyclic aromatic hydrocarbons (PAH) may be modified by the intake of antihistamine medications. Individual prenatal PAH exposure was assessed by personal air monitoring in 176 children who were followed over nine years, in the course of which outdoor residential air monitoring, allergic skin tests for indoor allergens, lung function tests (FVC, FEV(1), FEV(05), and FEF(25-75)) were performed. The analysis with the General Estimated Equation (GEE) showed no association between prenatal PAH exposure and lung function in the group of children who were reported to be antihistamine users. However, in the group of antihistamine non-users all lung function tests except for FEF(25-75) were significantly and inversely associated with prenatal airborne PAH exposure. The results of the study suggest that the intake of antihistamine medications in early childhood may inhibit the negative effect of fetal PAH exposure on lung growth and provides additional indirect evidence for the hypothesis that lung alterations in young children resulting from PAH exposure may be caused by the allergic inflammation within lung. © 2014 Wiley Periodicals, Inc.

  10. Feasibility of treating aged polycyclic aromatic hydrocarbons (PAHs)-contaminated soils using ethyl lactate-based Fenton treatment via parametric and kinetic studies.

    Science.gov (United States)

    Yap, Chiew Lin; Gan, Suyin; Ng, Hoon Kiat

    2015-01-01

    This study focuses on the feasibility of treating aged polycyclic aromatic hydrocarbons (PAHs)-contaminated soils using ethyl lactate (EL)-based Fenton treatment via a combination of parametric and kinetic studies. An optimised operating condition was observed at 66.7 M H2O2 with H2O2/Fe(2+) of 40:1 for low soil organic carbon (SOC) content and mildly acidic soil (pH 6.2), and 10:1 for high SOC and very acidic soil (pH 4.4) with no soil pH adjustment. The desorption kinetic was only mildly shifted from single equilibrium to dual equilibrium of the first-order kinetic model upon ageing. Pretreatment with EL fc = 0.60 greatly reduced the mass transfer coefficient especially for the slow desorbed fraction (kslow) of high molecular weight (HMW) PAHs, largely contributed by the concentration gradient created by EL-enhanced solubility. As the major desorption obstacle was almost fully overcome by the pretreatment, the pseudo-first-order kinetic reaction rate constant of PAHs degradation of aged soils was statistically discernible from that of freshly contaminated soils but slightly reduced in high SOC and high acidity soil. Stabilisation of H2O2 by EL addition in combination with reduced Fe(2+) catalyst were able to slow the decomposition rate of H2O2 even at higher soil pH.

  11. Gaseous polycyclic aromatic hydrocarbon concentrations are higher in urban forests than adjacent open areas during summer but not in winter – Exploratory study

    International Nuclear Information System (INIS)

    Viippola, Viljami; Rantalainen, Anna-Lea; Yli-Pelkonen, Vesa; Tervo, Peatta; Setälä, Heikki

    2016-01-01

    While the potential of plants to uptake polycyclic aromatic hydrocarbons (PAHs) is widely acknowledged, empirical evidence of the effects of this process on local atmospheric PAH concentrations and human health is tenuous. We measured gaseous PAH concentrations using passive samplers in urban tree-covered areas and adjacent open, treeless areas in a near-road environment in Finland to gain information on the ability of urban vegetation to improve air quality. The ability of urban, mostly deciduous, vegetation to affect PAHs was season dependent: during summer, concentrations were significantly higher in tree-covered areas, while in the fall, concentrations in open areas exceeded those in tree-covered areas. During winter, concentrations in tree-covered areas were either lower or did not differ from those in open areas. Results of this study imply that the commonly believed notion that trees unequivocally improve air quality does not apply to PAHs studied here. - Highlights: • Urban tree-cover increases gaseous PAH concentrations during summertime. • Elevated PAH concentrations do not clearly correspond with vegetation properties. • Tree-cover attenuates seasonal PAH concentration fluctuation. - Higher ambient gaseous PAH concentrations were detected within urban tree cover as compared to open areas during summertime.

  12. 425 Case study

    African Journals Online (AJOL)

    Marinda

    Anaesthesia management of acute aortic dissection type B in ... of a severe, constant abdominal and chest pain radiating to the ... Continuous spinal anaesthesia was induced ... these cases surgical intervention is critical.1,2 Type B of AAD is.

  13. Polycyclic aromatic hydrocarbons emitted from a hot-mix drum, asphalt plant: study of the influence from use of recycled bitumen

    Energy Technology Data Exchange (ETDEWEB)

    Ventura, A.; Jullien, A.; Moneron, P. [Lab. Central des Ponts et Chaussees, Div. Technologie du Genie Civil et Environnement, Section Developpement Durable, Bouguenais (France)

    2007-11-15

    A study was conducted to determine if the use of recycled asphalt aggregate influences emissions of polycyclic aromatic hydrocarbons (PAH). Hot bitumen contains PAH compounds which have been gaining increasing attention due to their toxicity. In addition, the energy consumed during asphalt mixing can reach 60 per cent of the total energy needed for the construction and maintenance of a road over a 30-year service life. Asphalt hot mixing is one of the most common processes found in the road sector. It requires warming and drying aggregate through combustion. In order to minimize emissions, the major influential parameters must be identified. A joint research program involving several institutions has been launched to conduct an experimental campaign on the Blois Hot Mix Asphalt plant, with quantification of the 16 PAH listed by the United States Environmental Protection Agency. Variations in asphalt recycling rate favour emissions of heavy molecular weight PAH, among those analysed. It was determined that specific markers of combustion and materials may contribute to a better understanding of the entire hot asphalt mixing process. It was suggested that chemical characterization of bitumen may help in predicting PAH emissions. 24 refs., 6 tabs., 5 figs.

  14. Influence of the method of production of eggs on the daily intake of polycyclic aromatic hydrocarbons and organochlorine contaminants: an independent study in the Canary Islands (Spain).

    Science.gov (United States)

    Luzardo, Octavio P; Rodríguez-Hernández, Angel; Quesada-Tacoronte, Yohana; Ruiz-Suárez, Norberto; Almeida-González, Maira; Henríquez-Hernández, Luis Alberto; Zumbado, Manuel; Boada, Luis D

    2013-10-01

    Analysis of 16 polycyclic aromatic hydrocarbons (PAHs), 20 organochlorine pesticides (OCPs) and 18 polychlorinated biphenyls (PCBs) were performed on eggs from three different production types (conventional, free-run and organic) collected from the markets of the Canary Islands (Spain). Unlike other studies we did not found differences in the content of PCBs or OCPs of eggs in relation to its production type. Median ∑OCPs content was 3.87 ng g⁻¹ fat, being dieldrin, dicofol, hexachlorobenzene, p,p'-DDE and p,p'-DDT the most frequently detected. Median ∑PCBs value was 3.93 ng g⁻¹ fat, with 79.9% of this amount coming from the marker PCBs. Two samples, one free-run and one organic, greatly exceeded the current European Commission (EC) limit of 2.5 pg TEQ(PCDD/F) g⁻¹ lipid, but the rest were well below of this limit. The concentrations of PAHs in conventionally produced eggs were almost 4 times higher than in free-run or organic eggs. Mean dietary intake estimates of the organochlorine contaminants based on consumption of eggs, regardless of the type chosen, is negligible for the Canary Islands' population. However, the median dietary intake estimates of PAHs greatly depend on the type of eggs chosen, being much lower when free-run and organic eggs are consumed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Emotion, Engagement, and Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman; Terry, David R.; Lemons, Paula; Armstrong, Norris; Brickman, Peggy; Ribbens, Eric

    2014-01-01

    Three college faculty taught large general biology classes using case studies and personal response systems (clickers). Each instructor taught the same eight cases in two different sections, except the questions within the cases differed. In one section the questions were lower order (LO) factual inquiries, and in the other they were largely…

  16. Molecular epidemiology studies of carcinogenic environmental pollutants. Effects of polycyclic aromatic hydrocarbons (PAHs) in environmental pollution on exogenous and oxidative DNA damage.

    Science.gov (United States)

    Farmer, Peter B; Singh, Rajinder; Kaur, Balvinder; Sram, Radim J; Binkova, Blanka; Kalina, Ivan; Popov, Todor A; Garte, Seymour; Taioli, Emanuela; Gabelova, Alena; Cebulska-Wasilewska, Antonina

    2003-11-01

    Exposure to high levels of environmental air pollution is known to be associated with an increased carcinogenic risk. The individual contribution to this risk derived from specific carcinogenic chemicals within the complex mixture of air pollution is less certain, but may be explored by the use of molecular epidemiological techniques. Measurements of biomarkers of exposure, of effect and of susceptibility provide information of potential benefit for epidemiological and cancer risk assessment. The application of such techniques has been mostly concerned in the past with the carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) that are associated with particulate matter in air pollution, and has showed clear evidence of genotoxic effects, such as DNA adducts, chromosome aberrations (CA) and ras oncogene overexpression, in environmentally exposed Czech and Polish populations. We are currently extending these studies by an investigation of populations exposed to environmental pollution in three European countries, Czech Republic, Slovak Republic and Bulgaria. This pays particular attention to PAHs, but also investigates the extent of radically induced (oxidative) DNA damage in the exposed populations. Policemen, bus drivers and controls, who carried personal monitors to determine their exposures to PAHs have been studied, and blood and urine were collected. Antioxidant and dietary status were assessed in these populations. Stationary monitors were also used for ambient air monitoring. Amongst the parameters studied in the biological samples were: (a) exposure biomarkers, such as PAH adducts with DNA, p53 and p21(WAF1) protein levels, (b) oxidative DNA damage, (c) the biological effect of the exposure by measurement of chromosome damage by fluorescence in situ hybridisation (FISH) or conventional methods, and (d) polymorphisms in carcinogen metabolising and DNA repair enzymes. Repair ability was also measured by the Comet assay. In vitro systems are being evaluated to

  17. Building theories from case study research: the progressive case study

    NARCIS (Netherlands)

    Steenhuis, H.J.; de Bruijn, E.J.

    2006-01-01

    Meredith (1998) argues for more case and field research studies in the field of operations management. Based on a literature review, we discuss several existing approaches to case studies and their characteristics. These approaches include; the Grounded Theory approach which proposes no prior

  18. Theory Testing Using Case Studies

    DEFF Research Database (Denmark)

    Møller, Ann-Kristina Løkke; Dissing Sørensen, Pernille

    2014-01-01

    The appropriateness of case studies as a tool for theory testing is still a controversial issue, and discussions about the weaknesses of such research designs have previously taken precedence over those about its strengths. The purpose of the paper is to examine and revive the approach of theory...... testing using case studies, including the associated research goal, analysis, and generalisability. We argue that research designs for theory testing using case studies differ from theorybuilding case study research designs because different research projects serve different purposes and follow different...... research paths....

  19. Birds and polycyclic aromatic hydrocarbons

    Science.gov (United States)

    Albers, P.H.

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAH) are present throughout the global environment and are produced naturally and by activities of humans. Effects of PAH on birds have been determined by studies employing egg injection, egg immersion, egg shell application, single and multiple oral doses, subcutaneous injection, and chemical analysis of field-collected eggs and tissue. The four-to six-ring aromatic compounds are the most toxic to embryos, young birds, and adult birds. For embryos, effects include death, developmental abnormalities, and a variety of cellular and biochemical responses. For adult and young birds, effects include reduced egg production and hatching, increased clutch or brood abandonment, reduced growth, increased organweights, and a variety of biochemical responses. Trophic level accumulation is unlikely. Environmental exposure to PAH in areas of high human population or habitats affected by recent petroleum spills might be sufficient to adversely affect reproduction. Evidence of long-term effects of elevated concentrations of environmental PAH on bird populations is very limited and the mechanisms of effect are unclear.

  20. Air pollution in relation to US cancer mortality rates: an ecological study; likely role of carbonaceous aerosols and polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Grant, W.B. [Sunlight Nutrients & Health Research Center SUNARC, San Francisco, CA (United States)

    2009-09-15

    There are large geographical variations of cancer mortality rates in the United States. In a series of ecological studies in the U.S., a number of risk-modifying factors including alcohol, diet, ethnic background, poverty, smoking, solar ultraviolet-B (UVB), and urban/rural residence have been linked to many types of cancer. Air pollution also plays a role in cancer risk. Cancer mortality rates averaged by state for two periods, 1950-1969 and 1970-1994, were used in multiple-linear regression analyses with respect to many, of the risk-modifying factors mentioned with the addition of an air pollution index in the form of a map of acid deposition in 1985. This index is correlated with emissions from coal-fired power plants. In addition, lung cancer mortality rates for five-Year periods from 1970-74 to 1990-94 were used in multiple linear regression analyses including air pollution and cigarette smoking. The air pollution index correlated with respiratory, digestive tract, urogenital, female, blood and skin cancer. Air pollution was estimated to account for 5% of male cancer deaths and 3% of female cancer deaths between 1970-1994. Solar UVB was inversely correlated with all these types of cancer except the respirator, skin and cervical cancer. Cigarette smoking was directly linked to lung cancer but not to other types of cancer in this study. Combustion of coal, diesel fuel and wood is the likely source of air pollution that affects cancer risk on a large scale, through production of black carbon aerosols with adsorbed polycyclic aromatic hydrocarbons.

  1. Depressed height gain of children associated with intrauterine exposure to polycyclic aromatic hydrocarbons (PAH) and heavy metals: the cohort prospective study.

    Science.gov (United States)

    Jedrychowski, Wiesław A; Perera, Frederica P; Majewska, Renata; Mrozek-Budzyn, Dorota; Mroz, Elżbieta; Roen, Emily L; Sowa, Agata; Jacek, Ryszard

    2015-01-01

    Fetal exposure to environmental toxicants may program the development of children and have long-lasting health impacts. The study tested the hypothesis that depressed height gain in childhood is associated with prenatal exposure to airborne polycyclic aromatic hydrocarbons (PAH) and heavy metals (lead and mercury). The study sample comprised 379 children born to non-smoking mothers among whom a total of 2011 height measurements were carried out over the 9-year follow-up period. Prenatal airborne PAH exposure was assessed by personal air monitoring of the mother in the second trimester of pregnancy and heavy metals were measured in cord blood. At the age of 3 residential air monitoring was done to evaluate the level of airborne PAH, and at the age 5 the levels of heavy metals were measured in capillary blood. The effect estimates of prenatal PAH exposure on height growth over the follow-up were adjusted in the General Estimated Equation (GEE) models for a wide set of relevant covariates. Prenatal exposure to airborne PAH showed a significant negative association with height growth, which was significantly decreased by 1.1cm at PAH level above 34.7 ng/m(3) (coeff.=-1.07, p=0.040). While prenatal lead exposure was not significantly associated with height restriction, the effect of mercury was inversely related to cord blood mercury concentration above 1.2 μg/L (coeff.=-1.21, p=0.020), The observed negative impact of prenatal PAH exposure on height gain in childhood was mainly mediated by shorter birth length related to maternal PAH exposure during pregnancy. The height gain deficit associated with prenatal mercury exposure was not seen at birth, but the height growth was significantly slower at later age. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Prenatal exposure to airborne polycyclic aromatic hydrocarbons and children's intelligence at 5 years of age in a prospective cohort study in Poland.

    Science.gov (United States)

    Edwards, Susan Claire; Jedrychowski, Wieslaw; Butscher, Maria; Camann, David; Kieltyka, Agnieszka; Mroz, Elzbieta; Flak, Elzbieta; Li, Zhigang; Wang, Shuang; Rauh, Virginia; Perera, Frederica

    2010-09-01

    In this prospective cohort study of Caucasian mothers and children in Krakow, Poland, we evaluated the role of prenatal exposure to urban air pollutants in the pathogenesis of neurobehavioral disorders. The objective of this study was to investigate the relationship between prenatal polycyclic aromatic hydrocarbon (PAH) exposure and child intelligence at 5 years of age, controlling for potential confounders suspected to play a role in neurodevelopment. A cohort of pregnant, healthy, nonsmoking women was enrolled in Krakow, Poland, between 2001 and 2006. During pregnancy, participants were invited to complete a questionnaire and undergo 48-hr personal air monitoring to estimate their babies' exposure, and to provide a blood sample and/or a cord blood sample at the time of delivery. Two hundred fourteen children were followed through 5 years of age, when their nonverbal reasoning ability was assessed using the Raven Coloured Progressive Matrices (RCPM). We found that higher (above the median of 17.96 ng/m3) prenatal exposure to airborne PAHs (range, 1.8-272.2 ng/m3) was associated with decreased RCPM scores at 5 years of age, after adjusting for potential confounding variables (n = 214). Further adjusting for maternal intelligence, lead, or dietary PAHs did not alter this association. The reduction in RCPM score associated with high airborne PAH exposure corresponded to an estimated average decrease of 3.8 IQ points. These results suggest that prenatal exposure to airborne PAHs adversely affects children's cognitive development by 5 years of age, with potential implications for school performance. They are consistent with a recent finding in a parallel cohort in New York City.

  3. Theory testing using case studies

    DEFF Research Database (Denmark)

    Dissing Sørensen, Pernille; Løkke Nielsen, Ann-Kristina

    2006-01-01

    on the strengths of theory-testing case studies. We specify research paths associated with theory testing in case studies and present a coherent argument for the logic of theoretical development and refinement using case studies. We emphasize different uses of rival explanations and their implications for research...... design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive......Case studies may have different research goals. One such goal is the testing of small-scale and middle-range theories. Theory testing refers to the critical examination, observation, and evaluation of the 'why' and 'how' of a specified phenomenon in a particular setting. In this paper, we focus...

  4. Fuzzy-Set Case Studies

    Science.gov (United States)

    Mikkelsen, Kim Sass

    2017-01-01

    Contemporary case studies rely on verbal arguments and set theory to build or evaluate theoretical claims. While existing procedures excel in the use of qualitative information (information about kind), they ignore quantitative information (information about degree) at central points of the analysis. Effectively, contemporary case studies rely on…

  5. Methodology for the case studies

    NARCIS (Netherlands)

    Smits, M.J.W.; Woltjer, G.B.

    2017-01-01

    This document is about the methodology and selection of the case studies. It is meant as a guideline for the case studies, and together with the other reports in this work package can be a source of inform ation for policy officers, interest groups and researchers evaluating or performing impact

  6. Case study - Argentina

    International Nuclear Information System (INIS)

    Diaz, E.

    1986-01-01

    Antecedents and experience of nuclear activities in Argentina; the Atomic Energy Commission (CNEA). First development and research activities. Research reactors and radioisotopes plants. Health physics and safety regulations. - Feasibility studies for the first nuclear power plant. Awarding the first plant CNA I (Atucha I). Relevant data related to the different project stages. Plant performance. - Feasibility study for the second nuclear power plant. Awarding the second plant CNE (Central Nuclear Embalse). Relevant data related to established targets. Differences compared with the first station targets. Local participation. Plant performance. (orig./GL)

  7. Case Study: Shiraz Women

    Directory of Open Access Journals (Sweden)

    Bijan Khajehnoori

    2011-04-01

    Full Text Available This study investigated the relationship between lifestyle which seems as a scale of globalization process with body image. Required data was collected by systematic random sampling among 508 women in Shiraz. Based on existing theories and studies theoretical framework has constituted based on Giddens theory. Six hypotheses have been established. For collecting information, survey method and self reported questionnaire were used. In data analysis and explanation, multiple regression and unilateral dispersion analyses were used. The result showed that among effective factors on body image, modern musical lifestyle, religious' lifestyle, leisure lifestyle and participative lifestyle explained 23 percent of variations of body image. Among these variables, only religious lifestyle had negative relationship with body image and other variables had positive relationship with dependant variable.

  8. Centrifugal compressor case study

    Energy Technology Data Exchange (ETDEWEB)

    Eckert, B.

    2010-10-15

    Three centrifugal compressors at a pipeline station were retrofitted with higher head impellers in 2008. The owners of the station experienced vibration problems over the following 2 years that caused transmitter and position failures that were assumed to be flow-induced pulsations. A vibration and pulsation analysis indicated that the shell mode piping vibration excited by the blade pass pulsation was responsible for the failures. This study outlined factors that contributed to the vibration problem. Interferences between the compressor and shell mode piping natural frequencies were predicted, and potential excitation sources were examined. The study demonstrated how centrifugal vibration analyses can be used during the design phase to avoid costly adjustments. Recommendations included the addition of stiffeners to alter the shell modes, and the addition of constrained layer damping material to reduce resonant responses. 2 refs., 1 tab., 12 figs.

  9. Case study: Tourism marketing

    OpenAIRE

    Kennell, James

    2014-01-01

    Tourism can be a challenging subject for students because it is both dynamic and susceptible to economic turbulence and shifts in trends. Tourism: A Modern Synthesis is an essential textbook for tourism students looking for a clear and comprehensive introduction to their studies which helps overcome these challenges. The authors apply a strong business approach to the subject reflecting developments in the teaching and content of modern courses and the text covers both key principles and cont...

  10. Case Study: Derechos Digitales

    Directory of Open Access Journals (Sweden)

    Cameron Neylon

    2017-10-01

    Full Text Available Derechos Digitales is a Latin American advocacy and research network focussed on freedom on the internet, privacy and copyright reform. For the pilot project a specific IDRC funded project was the notional focus of study. However in practice the effort for considering data sharing was aimed at being organisation wide. The organisation already shares reports and other resources (particularly images and infographics by default. While open data was described as being “in the DNA of the organisation” there was little practice across the network of sharing preliminary and in-process materials. Some aspects of data collection on research projects, particularly to do with copyright and legal issues, have significant privacy issues and as the organisation focuses on privacy as one of its advocacy areas this is taken very seriously. Many materials from research projects are not placed online at all. Derechos Digitales run distributed projects and this creates challenges for consistent management. Alongside this the main contact at DD changed during the course of the pilot. This exchange exemplified the challenges of maintaining organisational systems and awareness through a personnel change.

  11. Epoxide-Opening Cascades in the Synthesis of Polycyclic Polyether Natural Products

    Science.gov (United States)

    2009-01-01

    The group of polycyclic polyether natural products is of special interest due to the fascinating structure and biological effects displayed by its members. The latter includes potentially therapeutic antibiotic, antifungal, and anticancer properties, as well as extreme lethality. The polycyclic structural features of this family can, in some cases, be traced to their biosynthetic origin, but in others that are less well understood, only to proposed biosynthetic pathways that feature dramatic, yet speculative, epoxide–opening cascades. In this review we summarize how such epoxide–opening cascade reactions have been used in the synthesis of polycyclic polyethers and related natural products. PMID:19572302

  12. Case study: Khoramdareh County

    Directory of Open Access Journals (Sweden)

    Vahid Riahi Riahi

    2016-10-01

    Full Text Available Environmental sustainability of rural settlements based on a systematic viewpoint may be defined as a realization of sustainable development in different social, economic and environmental aspects of rural areas. Achieving this goal requires that we pay more attention to effective elements and factors through a set of sustainability indices. This research was meant to analyze sustainable factors of rural settlement in three dimensions: environmental, social and economic context using multi-criteria decision analysis and explanation of the relationships between its active and effective factors in the rural area of the Khorramdarreh County in the province of Zanjan. The research method used is the descriptive analytic approach. Data from 287 households were sampled randomly from a total of 1143 households in the four villages including: Rahmat Abad, Alvand, Baghdareh and, Sukhariz (out of 15 villages in the Khorramdarreh County. In the process of doing this research and after calculating the weights, the difference in the sustainability of environmental, social, economic and physical aspects in rural areas of this county have been determined. Data was collected using library and field research through questionnaires. Data analysis was performed by the One-Sample t Test and the Vikur and path analysis techniques, using statistical software SPSS. The findings show that environmental sustainability in the study area is half desirable. Among the different aspects of environmental sustainability, the most effective factors are physical, economic, social and environmental aspects, respectively. Little attention of policy-making –system to socio-cultural and environmental aspects, especially in practice, and rapid and unplanned utilization of production resources are the most important factors affecting this situation in two given dimensions. Although, in programmed documents the planning system agents emphasize on the socio-cultural sustainability

  13. Mild acid and alkali treated clay minerals enhance bioremediation of polycyclic aromatic hydrocarbons in long-term contaminated soil: A 14C-tracer study.

    Science.gov (United States)

    Biswas, Bhabananda; Sarkar, Binoy; Rusmin, Ruhaida; Naidu, Ravi

    2017-04-01

    Bioremediation of polycyclic aromatic hydrocarbon (PAH)-contaminated soils requires a higher microbial viability and an increased PAH bioavailability. The clay/modified clay-modulated bacterial degradation could deliver a more efficient removal of PAHs in soils depending on the bioavailability of the compounds. In this study, we modified clay minerals (smectite and palygorskite) with mild acid (HCl) and alkali (NaOH) treatments (0.5-3 M), which increased the surface area and pore volume of the products, and removed the impurities without collapsing the crystalline structure of clay minerals. In soil incubation studies, supplements with the clay products increased bacterial growth in the order: 0.5 M HCl ≥ unmodified ≥ 0.5 M NaOH ≥ 3 M NaOH ≥ 3 M HCl for smectite, and 0.5 M HCl ≥ 3 M NaOH ≥ 0.5 M NaOH ≥ 3 M HCl ≥ unmodified for palygorskite. A 14 C-tracing study showed that the mild acid/alkali-treated clay products increased the PAH biodegradation (5-8%) in the order of 0.5 M HCl ≥ unmodified > 3 M NaOH ≥ 0.5 M NaOH for smectite, and 0.5 M HCl > 0.5 M NaOH ≥ unmodified ≥ 3 M NaOH for palygorskite. The biodegradation was correlated (r = 0.81) with the bioavailable fraction of PAHs and microbial growth as affected particularly by the 0.5 M HCl and 0.5 M NaOH-treated clay minerals. These results could be pivotal in developing a clay-modulated bioremediation technology for cleaning up PAH-contaminated soils and sediments in the field. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Case studies of uncommon headaches.

    Science.gov (United States)

    Evans, Randolph W

    2006-05-01

    The following interesting and uncommon headache disorders are presented through case studies: exploding head syndrome, hypnic headache, neck-tongue syndrome, "Alice in Wonderland" syndrome, nummular headache, red ear syndrome, burning mouth syndrome, spontaneous intracranial hypotension syndrome, and cardiac cephalalgia.

  15. HYDROGEOLOGIC CASE STUDIES (DENVER PRESENTATION)

    Science.gov (United States)

    Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

  16. HYDROGEOLOGIC CASE STUDIES (CHICAGO, IL)

    Science.gov (United States)

    Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

  17. Hydrogeologic Case Studies (Seattle, WA)

    Science.gov (United States)

    Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

  18. a case study ondo state

    African Journals Online (AJOL)

    user

    the design of a Government Cloud (G-Cloud) network for Ondo State Government which will ... network for a developing economy; a case study of ... France is one of those countries that favour .... Arequipa city. .... Where region 0 = Akure, 1 =.

  19. One-year study of polycyclic aromatic compounds at an urban site in Grenoble (France): Seasonal variations, gas/particle partitioning and cancer risk estimation

    Energy Technology Data Exchange (ETDEWEB)

    Tomaz, Sophie [Institut National de l' Environnement industriel et des RISques (INERIS), Parc Technologique Alata BP2, 60550 Verneuil en Halatte (France); CNRS, EPOC, UMR 5805, F-33405 Talence Cedex (France); Université de Bordeaux, EPOC, UMR 5805, F-33405, Talence Cedex (France); Shahpoury, Pourya [Max Planck Institute for Chemistry, Multiphase Chemistry Department, Mainz (Germany); Jaffrezo, Jean-Luc [Laboratoire de Glaciologie et Géophysiques de l' Environnement (LGGE), Université de Grenoble-Alpes/CNRS, Grenoble (France); Lammel, Gerhard [Max Planck Institute for Chemistry, Multiphase Chemistry Department, Mainz (Germany); Masaryk University, Research Centre for Toxic Compounds in the Environment, Brno (Czech Republic); Perraudin, Emilie; Villenave, Eric [CNRS, EPOC, UMR 5805, F-33405 Talence Cedex (France); Université de Bordeaux, EPOC, UMR 5805, F-33405, Talence Cedex (France); Albinet, Alexandre, E-mail: alexandre.albinet@gmail.com [Institut National de l' Environnement industriel et des RISques (INERIS), Parc Technologique Alata BP2, 60550 Verneuil en Halatte (France)

    2016-09-15

    21 PAHs, 27 oxy-PAHs and 32 nitro-PAHs were measured every third day over a year in both gaseous (G) and particulate PM{sub 10} (P) phases in ambient air of Grenoble (France). Mean total concentrations (G + P) of PAHs and oxy-PAHs were in the same range and about 10 ng m{sup −3}. Nitro-PAHs were 50 to 100 times less concentrated averaging 100 pg m{sup −3}. Polycyclic aromatic compound (PAC) concentrations were 5 to 7 times higher in “cold” period (October to March) than in “warm” period (April to September). Seasonal variations may be explained by higher primary emissions from residential heating, especially biomass burning in “cold” season. Meteorological conditions and influence of the geomorphology around Grenoble, with the formation of thermal inversion layers leading to the stagnation of pollutants, were additional key parameters. Maximum individual PAC concentrations were observed during two PM{sub 10} pollution events in December and February–March. Chemical processes and secondary formation of oxy- and nitro-PAH were probably enhanced by the accumulation of the pollutants during these events. PAC gas/particle partitioning depended on compound molecular weight and vapour pressure. Gas/particle partitioning of oxy- and nitro-PAHs were evaluated using a multi-phase poly-parameter linear free energy relationship model. The PAC cancer risk was assessed using toxic equivalency factors available in the literature (19 PAHs, 10 nitro-PAHs and 1 oxy-PAH). Overall, particle-bound PACs contributed about 76% of the cancer risk. While PAHs accounted for most of the total PAC cancer risk, oxy- and nitro-PAHs could account for up to 24%. The risk quantification across substance classes is limited by toxicological data availability. - Highlights: • The most comprehensive study about PAH, nitro- and oxy-PAH in ambient air. • 80 species studied in gaseous and particle phases over a year at French urban site. • Concentration seasonality governed by

  20. Impact of barbecued meat consumed in pregnancy on birth outcomes accounting for personal prenatal exposure to airborne polycyclic aromatic hydrocarbons: Birth cohort study in Poland.

    Science.gov (United States)

    Jedrychowski, Wieslaw; Perera, Frederica P; Tang, Deliang; Stigter, Laura; Mroz, Elzbieta; Flak, Elzbieta; Spengler, John; Budzyn-Mrozek, Dorota; Kaim, Irena; Jacek, Ryszard

    2012-04-01

    We previously reported an association between prenatal exposure to airborne polycyclic aromatic hydrocarbons (PAH) and lower birth weight, birth length, and head circumference. The main goal of the present analysis was to assess the possible impact of coexposure to PAH-containing barbecued meat consumed during pregnancy on birth outcomes. The birth cohort consisted of 432 pregnant women who gave birth at term (>36 wk of gestation). Only non-smoking women with singleton pregnancies, 18-35 y of age, and who were free from chronic diseases such as diabetes and hypertension, were included in the study. Detailed information on diet over pregnancy was collected through interviews and the measurement of exposure to airborne PAHs was carried out by personal air monitoring during the second trimester of pregnancy. The effect of barbecued meat consumption on birth outcomes (birth weight, length, and head circumference at birth) was adjusted in multiple linear regression models for potential confounding factors such as prenatal exposure to airborne PAHs, child's sex, gestational age, parity, size of mother (maternal prepregnancy weight, weight gain in pregnancy), and prenatal environmental tobacco smoke. The multivariable regression model showed a significant deficit in birth weight associated with barbecued meat consumption in pregnancy (coeff = -106.0 g; 95%CI: -293.3, -35.8). The effect of exposure to airborne PAHs was about the same magnitude order (coeff. = -164.6 g; 95%CI: -172.3, -34.7). Combined effect of both sources of exposure amounted to birth weight deficit of 214.3 g (95%CI: -419.0, -9.6). Regression models performed for birth length and head circumference showed similar trends but the estimated effects were of borderline significance level. As the intake of barbecued meat did not affect the duration of pregnancy, the reduced birth weight could not have been mediated by a shortened gestation period. In conclusion, the study results provided epidemiologic

  1. Effect of Prenatal Polycyclic Aromatic Hydrocarbons Exposure on Birth Outcomes: The Polish Mother and Child Cohort Study

    Directory of Open Access Journals (Sweden)

    Kinga Polanska

    2014-01-01

    Full Text Available The aim of this study was to assess the impact of PAH exposure on various anthropometric measures of birth outcomes. The study population consisted of 210 nonsmoking pregnant women. Urine samples collected between 20th and 24th week of pregnancy were used for analysis of the following PAH metabolites: 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene (1-, 2-, 3-, 4-, and 9-OH-PHE, 1-hydroxypyrene (1-OH-PYR, 1,6 + 1,8-dihydroxypyrene (DI-OH-PYR, phenanthrene trans-1,2-dihydrodiol (PHE-1,2-diol, and phenanthrene trans-9,10-dihydrodiol (PHE-9,10-diol by gas chromatography-mass spectrometry. Environmental tobacco smoke exposure (ETS was assessed by cotinine level in saliva using a stable isotope dilution LC-ESI-MS/MS method. The mean PAH metabolite concentrations were in the range of 0.15 µg/g creatinine for 9-OH-PHE to 5.9 µg/g creatinine for PHE-9,10-diol. It was shown that none of the individual PAH exposure markers demonstrate a statistically significant influence on birth outcomes. Interestingly a statistically significant association was found between the sum of OH-PHE along with cotinine level and the cephalization index after adjusting for potential confounders (P=0.04. This study provides evidence that combined exposure of pregnant women to common environmental pollutants such as PAH and ETS might adversely affect fetal development. Thus, reduction of human exposure to these mixtures of hazardous compounds would in particular result in substantial health benefits for newborns.

  2. Effect of prenatal polycyclic aromatic hydrocarbons exposure on birth outcomes: the Polish mother and child cohort study.

    Science.gov (United States)

    Polanska, Kinga; Dettbarn, Gerhard; Jurewicz, Joanna; Sobala, Wojciech; Magnus, Per; Seidel, Albrecht; Hanke, Wojciech

    2014-01-01

    The aim of this study was to assess the impact of PAH exposure on various anthropometric measures of birth outcomes. The study population consisted of 210 nonsmoking pregnant women. Urine samples collected between 20th and 24th week of pregnancy were used for analysis of the following PAH metabolites: 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene (1-, 2-, 3-, 4-, and 9-OH-PHE), 1-hydroxypyrene (1-OH-PYR), 1,6 + 1,8-dihydroxypyrene (DI-OH-PYR), phenanthrene trans-1,2-dihydrodiol (PHE-1,2-diol), and phenanthrene trans-9,10-dihydrodiol (PHE-9,10-diol) by gas chromatography-mass spectrometry. Environmental tobacco smoke exposure (ETS) was assessed by cotinine level in saliva using a stable isotope dilution LC-ESI-MS/MS method. The mean PAH metabolite concentrations were in the range of 0.15 µg/g creatinine for 9-OH-PHE to 5.9 µg/g creatinine for PHE-9,10-diol. It was shown that none of the individual PAH exposure markers demonstrate a statistically significant influence on birth outcomes. Interestingly a statistically significant association was found between the sum of OH-PHE along with cotinine level and the cephalization index after adjusting for potential confounders (P = 0.04). This study provides evidence that combined exposure of pregnant women to common environmental pollutants such as PAH and ETS might adversely affect fetal development. Thus, reduction of human exposure to these mixtures of hazardous compounds would in particular result in substantial health benefits for newborns.

  3. Assessment of polycyclic aromatic hydrocarbons (PAHs) pollution in soil of suburban areas in Tianjin, China.

    Science.gov (United States)

    Lv, Jungang; Shi, Rongguang; Cai, Yanming; Liu, Yong

    2010-07-01

    Soil contamination with polycyclic aromatic hydrocarbons is an increasing problem and has aroused more and more concern in many countries, including China. In this study, representative soil samples (n = 87) of suburban areas in Tianjin (Xiqing, Dongli, Jinnan, Beichen) were evaluated for 16 polycyclic aromatic hydrocarbons. Surface soil samples were air-dried and sieved. Microwave assisted extraction was used for polycyclic aromatic hydrocarbons preparation prior to analysis with gas chromatography-mass spectrometry. The total concentrations of tested polycyclic aromatic hydrocarbons in Xiqing, Dongli, Jinnan, Beichen ranged in 58.5-2,748.3, 36.1-6,734.7, 58.5-4,502.5, 29.7-852.5 ng/g and the averages of total concentration of polycyclic aromatic hydrocarbons were 600.5, 933.6, 640.8, 257.3 ng/g, respectively. Spatial variation of polycyclic aromatic hydrocarbons in soil was illustrated; Pollution status and comparison to other cities were also investigated. Serious polycyclic aromatic hydrocarbons soil pollution was found in Dongli district, on the contrary, Bap in most sites in Beichen did not exceed relative standards and most sites in Beichen should be classified as non-contaminated soil. Principal component analysis was used to identify the possible sources of different districts. It turned out that coal combustion still was the most important sources in three districts except Beichen. Coking, traffic, cooking, biomass combustion also accounted for polycyclic aromatic hydrocarbons pollution to certain extent in different districts. These data can be further used to assess the health risk associated with soils polluted with polycyclic aromatic hydrocarbons and help local government find proper way to reduce polycyclic aromatic hydrocarbons pollution in soils.

  4. Teaching Case: Enterprise Architecture Specification Case Study

    Science.gov (United States)

    Steenkamp, Annette Lerine; Alawdah, Amal; Almasri, Osama; Gai, Keke; Khattab, Nidal; Swaby, Carval; Abaas, Ramy

    2013-01-01

    A graduate course in enterprise architecture had a team project component in which a real-world business case, provided by an industry sponsor, formed the basis of the project charter and the architecture statement of work. The paper aims to share the team project experience on developing the architecture specifications based on the business case…

  5. Theory Testing Using Case Studies

    DEFF Research Database (Denmark)

    Sørensen, Pernille Dissing; Løkke, Ann-Kristina

    2006-01-01

    design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive...

  6. Microbial Degradation of Polycyclic Aromatic Hydrocarbons and Characterization of Bacteria

    Science.gov (United States)

    Tikilili, P. V.; Chirwa, E. M. N.

    2010-01-01

    Biodegradation of polycyclic aromatic hydrocarbons was studied. Naphthalene was used as a model compound to represent these compounds. Low initial concentrations of naphthalene in a range of 30-60 mg/L were completely degraded after incubation for 15 hrs by consortia from a landfill soil while consortia from minewater took more that 29 hrs to reach complete degradation.

  7. Photolytic and radiolytic destruction of natural polycyclic mycotoxins

    International Nuclear Information System (INIS)

    Mammadov, Kh. F

    2011-01-01

    Full text: The kinetics of degradation of natural polycyclic toxins in grains and dried fruits under the influence of UV-light and ionizing radiation 60 C and the probability of radiolytic detoxication of these products has been studied for the first time

  8. Effect of smoking on Polycyclic Aromatic Hydrocarbons (PAHS ...

    African Journals Online (AJOL)

    The effects of smoking on proximate composition, energy values and concentrations of polycyclic aromatic hydrocarbons (PAHs) were studied in raw and smoked samples of catfish (Clarias gariepinus) and tilapia (Oreochromis niloticus). Crude protein was higher in the tilapia sample for both raw and smoked samples.

  9. Case Study of 'moral injury' : Format Dutch Case Studies Project

    NARCIS (Netherlands)

    Korver, Sjaak; Walton, Martin N.; van Loenen, Guus

    2017-01-01

    The case study ‘Moral Injury’ traces care provided by a chaplain in a mental health institution to a former military marksman named Hans. Hans was in care at a specialized unit for military veterans with traumas. He sought contact with a chaplain “to set things right with God” and wanted the

  10. eCompetence Case Studies

    DEFF Research Database (Denmark)

    Jensen, Helle Bækkelund

    2006-01-01

    In this paper we present some details of the processes undertaken in the European eCompetence Initiative. We present two illustrative and representative case studies. The research aims to identify and understand patterns of individual and organisational eCompetence approaches.......In this paper we present some details of the processes undertaken in the European eCompetence Initiative. We present two illustrative and representative case studies. The research aims to identify and understand patterns of individual and organisational eCompetence approaches....

  11. Case Study on Logistics Performance

    Directory of Open Access Journals (Sweden)

    Shahryar Sorooshian

    2013-05-01

    Full Text Available The paper presents research carried out at a medium‐size manufacturing organization in east Asia. The study tries to highlight the importance of supply chain management; specifically, our aim for this study is to understand logistics and performance measurement in the logistics and supply chain, and we include a theoretical discussion of online data collected and a case study of the logistic performance of a real organization. The study also examines the performance of the selected company, identifies the problems and provides recommendations for improvements. This study can be a guide for business advisers and those interested in analysing company performance, especially from a logistics viewpoint. We also suggest the methodology of this case study for those who want to have a better understanding of a business environment before starting their own business, or for benchmarking practice during strategic planning.

  12. BioFleet case studies

    International Nuclear Information System (INIS)

    2007-01-01

    These six case studies examined the use of different biodiesel blends as fuel supply sources for businesses in British Columbia (BC). In the first case study, 6 municipalities participated in a pilot program designed to compare the performance of biodiesel and diesel fuels. Each municipality operated 2 base vehicles running on conventional diesel along with 2 similar vehicles which used biodiesel. Real time emissions tests and analyses of the vehicles using biodiesel were also conducted by 2 of the participating municipalities. All municipalities participating in the study agreed to purchase significant volumes of biodiesel. The second case study described a pilot study conducted by the City of Vancouver's equipment services branch in 2004. As a result of the study, the city now has over 530 types of equipment that use biodiesel. The third case study described a program designed by TSI Terminals in Vancouver to assess the emission reduction impact of using biodiesel at its port facility. Six different pieces of equipment were used to confirm that biodiesel could be used throughout the terminal. Test results confirmed that biodiesel blends could be used to reduce emissions. Overall emissions were reduced by 30 per cent. The fourth case study described a waste renderer that used a fleet of 36 trucks to deliver raw products to its plants. The company made the decision to use only biodiesel for its entire fleet of trucks. Since July 2005, the company has logged over 1.7 million km using biodiesel blends. The fifth case study described a salmon hatchery that switched from diesel to biodiesel in order to reduce emissions. The biodiesel blends are used to fuel the hatchery's 2 diesel generators. The hatchery has reduced emissions of greenhouse gases (GHGs) by an estimated 1800 tonnes annually. The sixth case study described how the Township of Langley has started using biodiesel for its entire fleet of of approximately 250 pieces of equipment. The township has not

  13. The effects of polycyclic aromatic hydrocarbons on the immune system of fish: A review

    International Nuclear Information System (INIS)

    Reynaud, S.; Deschaux, P.

    2006-01-01

    Polycyclic aromatic hydrocarbons are an important class of environmental pollutants that are known to be carcinogenic and immunotoxic. This review summarizes the diverse literature on the effects of these pollutants on innate and acquired immunity in fish and the mechanism of PAH-induced immunotoxicity. Among innate immune parameters, many authors have focused on macrophage activities in fish exposed to polycyclic aromatic hydrocarbons. Macrophage respiratory burst appears especially sensitive to polycyclic aromatic hydrocarbons. Among acquired immune parameters, lymphocyte proliferation appears highly sensitive to polycyclic aromatic hydrocarbon exposure. However, the effects of polycyclic aromatic hydrocarbons on both specific and non-specific immunity are contradictory and depend on the mode of exposure, the dose used or the species studied. In contrast to mammals, fewer studies have been done in fish to determine the mechanism of polycyclic aromatic hydrocarbon-induced toxicity. This phenomenon seems to implicate different intracellular mechanisms such as metabolism by cytochrome P4501A, binding to the Ah-receptor, or increased intracellular calcium. Advances in basic knowledge of fish immunity should lead to improvements in monitoring fish health and predicting the impact of polycyclic aromatic hydrocarbons on fish populations, which is a fundamental ecotoxicological goal

  14. The effects of polycyclic aromatic hydrocarbons on the immune system of fish: A review

    Energy Technology Data Exchange (ETDEWEB)

    Reynaud, S. [Laboratoire d' Ecologie Alpine. UMR CNRS 5553. Universite Joseph Fourier. BP 53. 38041 Grenoble cedex 9 (France) and Laboratory of General and Comparative Immunophysiology, Science Teaching and Research Unit, 123, av. Albert Thomas, 87060 Limoges (France)]. E-mail: stephane.reynaud@ujf-grenoble.fr; Deschaux, P. [Laboratory of General and Comparative Immunophysiology, Science Teaching and Research Unit, 123, av. Albert Thomas, 87060 Limoges (France)

    2006-05-01

    Polycyclic aromatic hydrocarbons are an important class of environmental pollutants that are known to be carcinogenic and immunotoxic. This review summarizes the diverse literature on the effects of these pollutants on innate and acquired immunity in fish and the mechanism of PAH-induced immunotoxicity. Among innate immune parameters, many authors have focused on macrophage activities in fish exposed to polycyclic aromatic hydrocarbons. Macrophage respiratory burst appears especially sensitive to polycyclic aromatic hydrocarbons. Among acquired immune parameters, lymphocyte proliferation appears highly sensitive to polycyclic aromatic hydrocarbon exposure. However, the effects of polycyclic aromatic hydrocarbons on both specific and non-specific immunity are contradictory and depend on the mode of exposure, the dose used or the species studied. In contrast to mammals, fewer studies have been done in fish to determine the mechanism of polycyclic aromatic hydrocarbon-induced toxicity. This phenomenon seems to implicate different intracellular mechanisms such as metabolism by cytochrome P4501A, binding to the Ah-receptor, or increased intracellular calcium. Advances in basic knowledge of fish immunity should lead to improvements in monitoring fish health and predicting the impact of polycyclic aromatic hydrocarbons on fish populations, which is a fundamental ecotoxicological goal.

  15. Case Studies in Sports Nutrition.

    Science.gov (United States)

    Clark, Nancy

    1988-01-01

    This article presents case studies of two athletes who wanted to affect a change in their body weight in order to enhance athletic performance. Each athlete's problem and the nutrition approach used to solve it are discussed. Caloric values of fast foods are listed. (JL)

  16. Shea case study Burkina Faso

    NARCIS (Netherlands)

    S. Drost (Sarah); J.C.A.C. van Wijk (Jeroen); S.R. Vellema (Sietze)

    2012-01-01

    textabstractThis shea case study is part of a larger Partnerships Resource Centre (PrC) project elaborated in tandem with two Dutch non-governmental organisations (NGOs); ICCO and Oxfam Novib. The endeavour of this ‘action research’ project is to combine the expert knowledge of development

  17. The reflexive case study method

    DEFF Research Database (Denmark)

    Rittenhofer, Iris

    2015-01-01

    This paper extends the international business research on small to medium-sized enterprises (SME) at the nexus of globalization. Based on a conceptual synthesis across disciplines and theoretical perspectives, it offers management research a reflexive method for case study research of postnational...

  18. Determination of carcinogenic polycyclic aromatic hydrocarbons in ...

    African Journals Online (AJOL)

    Determination of carcinogenic polycyclic aromatic hydrocarbons in air samples in Irbid, north Jordan. A Al-Gawadreh Sat, M.B. Gasim, A.R. Hassan, A Azid. Abstract. Air samples were collected at an urban site and a rural (BERQESH) site during February (2017) until March (2017) to determine concentrations of polycyclic ...

  19. Flow cytometry detection of planktonic cells with polycyclic aromatic hydrocarbons sorbed to cell surfaces

    KAUST Repository

    Cerezo, Maria I.; Linden, Matthew; Agusti, Susana

    2017-01-01

    Polycyclic aromatic hydrocarbons are very important components of oil pollution. These pollutants tend to sorb to cell surfaces, exerting toxic effects on organisms. Our study developed a flow cytometric method for the detection of PAHs sorbed

  20. Multispecies and monoculture rhizoremediation of polycyclic aromatic hydrocarbons (PAHs) from the soil

    CSIR Research Space (South Africa)

    Maila, MP

    2005-01-01

    Full Text Available In this study, the authors investigated the potential of multispecies rhizoremediation and monoculture rhizoremediation in decontaminating polycyclic aromatic hydrocarbon (PAH) contaminated soil. Plant-mediated PAH dissipation was evaluated using...

  1. Investigation of sulfur-polycyclic aromatic hydrocarbon in coal derived tars of pyrolysis and hydropyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.; Li, B.; Zhang, B. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion

    1999-07-01

    A study was undertaken to characterize sulphur forms in coal derived tars from pyrolysis and hydropyrolysis of bituminous coal and lignite. The pyrolysis tars were analyzed for content of polycyclic aromatic sulfur hydrocarbons (PASH). 5 refs., 3 figs., 3 tabs.

  2. Ex-situ bioremediation of polycyclic aromatic hydrocarbons in sewage sludge

    DEFF Research Database (Denmark)

    Larsen, Sille Bendix; Karakashev, Dimitar Borisov; Angelidaki, Irini

    2009-01-01

    Polycyclic aromatic hydrocarbons (PAH) are regarded as environmental pollutants. A promising approach to reduce PAH pollution is based on the implementation of the natural potential of some microorganisms to utilize hydrocarbons. In this study Proteiniphilum acetatigenes was used for bioaugmentat...

  3. Institutional total energy case studies

    Energy Technology Data Exchange (ETDEWEB)

    Wulfinghoff, D.

    1979-07-01

    Profiles of three total energy systems in institutional settings are provided in this report. The plants are those of Franciscan Hospital, a 384-bed facility in Rock Island, Illinois; Franklin Foundation Hospital, a 100-bed hospital in Franklin, Louisiana; and the North American Air Defense Command Cheyenne Mountain Complex, a military installation near Colorado Springs, Colorado. The case studies include descriptions of plant components and configurations, operation and maintenance procedures, reliability, relationships to public utilities, staffing, economic efficiency, and factors contributing to success.

  4. Stochastic efficiency: five case studies

    International Nuclear Information System (INIS)

    Proesmans, Karel; Broeck, Christian Van den

    2015-01-01

    Stochastic efficiency is evaluated in five case studies: driven Brownian motion, effusion with a thermo-chemical and thermo-velocity gradient, a quantum dot and a model for information to work conversion. The salient features of stochastic efficiency, including the maximum of the large deviation function at the reversible efficiency, are reproduced. The approach to and extrapolation into the asymptotic time regime are documented. (paper)

  5. Case Study: Guidelines for Producing Videos to Accompany Flipped Cases

    Science.gov (United States)

    Prud'homme-Généreux, Annie; Schiller, Nancy A.; Wild, John H.; Herreid, Clyde Freeman

    2017-01-01

    Three years ago, the "National Center for Case Study Teaching in Science" (NCCSTS) was inspired to merge the case study and flipped classroom approaches. The resulting project aimed to create the materials required to teach a flipped course in introductory biology by assigning videos as homework and case studies in the classroom. Three…

  6. CAREM X INPRO case study

    International Nuclear Information System (INIS)

    Florido, P.C.; Brasnarof, D.; Delmastro, D.; Azpitarte, O.E.

    2004-01-01

    In order to assess and compare the performance of innovative nuclear energy systems INPRO has defined a set of basic principles, user requirements and criteria to be met in different areas (economics, sustainability and environment, safety, waste management and proliferation). This paper illustrates the use of INPRO methodology to a particular reactor system. Argentina is performing CAREM X Nuclear System Case Study based on CAREM nuclear reactor and Once Through Fuel Cycle, using SIGMA for enriched uranium production, and a deep geological repository for final disposal of high level waste after surface intermediate storage in horizontal natural convection silos, to verify INPRO (International Project on Innovative Nuclear Reactors and Fuel Cycles) methodology. 6 aspects have been considered: 1) enrichment based on Sigma enrichment plant (gas diffusion technology), 2) conversion to UO 2 , 3) fuel manufacturing, 4) CAREM-300 based reactor technology, 5) intermediate spent fuel storage, and 6) deep geological repository of spent fuels. Projections show that developing countries could play a crucial role in the deployment of nuclear energy, in the next fifty years. This case study will be highly useful for checking INPRO methodology for this scenario. In this paper, the preliminary findings of the Case Study are presented, including proposals to improve the INPRO methodology

  7. The distribution and sources of polycyclic aromatic hydrocarbons in shallow groundwater from an alluvial-diluvial fan of the Hutuo River in North China

    Science.gov (United States)

    Wang, Jincui; Zhao, Yongsheng; Sun, Jichao; Zhang, Ying; Liu, Chunyan

    2018-06-01

    This paper has investigated the concentration and distribution of polycyclic aromatic hydrocarbons in shallow groundwater from an alluvial-diluvial fan of the Hutuo River in North China. Results show that the concentration levels of 16 priority polycyclic aromatic hydrocarbons range from 0 to 92.06 ng/L, do not conform to drinking water quality standards in China (GB 5749- 2006). However, the concentration figures of priority polycyclic aromatic hydrocarbons are much lower than that of other studies conducted elsewhere in China. In addition, highly-concentrated polycyclic aromatic hydrocarbons (50-92 ng/L) are fragmentarily distributed. The composition of polycyclic aromatic hydrocarbons from this study indicates that low molecular polycyclic aromatic hydrocarbons are predominant in groundwater samples, medium molecular compounds occur at low concentrations, and high molecular hydrocarbons are not detected. The polycyclic aromatic hydrocarbon composition in groundwater samples is basically the same as that of gaseous samples in the atmosphere in this study. Therefore, the atmospheric input is assumed to be an important source of polycyclic aromatic hydrocarbons, no less than wastewater discharge, adhesion on suspended solids, and surface water leakage. Ratios of specific polycyclic aromatic hydrocarbons demonstrate that they mainly originate from wood or coal combustion as well as natural gas and partially from petroleum according to the result of principal component analysis. On the whole, conclusions are drawn that the contamination sources of these polycyclic aromatic hydrocarbons are likely petrogenic and pyrolytic inputs. Future investigations by sampling topsoil, vadose soil, and the atmosphere can further verify aforementioned conclusions.

  8. A case study of Impetigo

    Directory of Open Access Journals (Sweden)

    Mansouri P

    1993-05-01

    Full Text Available This is a report of a case study on 234 patients with impetigo who referred to Razi Dermatology Hospital from April to November, 1989. Treatment was started immediately after obtaining direct smear and performing culture and antibiotic sensitivity test. The most common organism responsible for impetigo was the coagulase-positive staphylococcus (71%. In 13.7% of the cases, the coagulase-negative staphylococcus was grown on culture media, but none of the cultures showed streptococcus as the main organism. Treatment was started with oral penicillin V, oral erythromycin, benzathine penicillin G injection, oral cephalexin, and topical fuccidin. Clinical and bacteriological evaluation after 3-7 days showed that it is preferable to use oral cephalexin instead of other protocols such as oral erythromycin, which has previously been the drug of choice for impetigo. In addition, topical fuccidin with a 75% curative rate was the first drug for treatment, with the same effect as the oral cephalexin

  9. MULTIPLE PERSONALITY: CASE REPORT STUDY

    Directory of Open Access Journals (Sweden)

    Miloš Židanik

    2004-07-01

    Full Text Available Background. Multiple personality disorder is characterised by splited individual ego-states and splited professional community arguing whether this disorder actually exists or not.Methods. In this case report study a supportive psychodynamic psychotherapy of a patient with multiple personality disorder is presented, that lasted for 4.5 years and resulted in ego-reintegration.Conclusions. The spliting between different ego-states is powered by unneutralised aggression with the possibility of hetero- and autoaggressive behaviour. Therefore the patient in the analytically oriented psychotherapeutic process is at high risk and a safe therapeutic (e. g. in-patient setting has to be provided.

  10. Overview of the Case Studies

    DEFF Research Database (Denmark)

    Cameron, Ian; Gani, Rafiqul

    2011-01-01

    A series of case studies are used to illustrate many of the underlying modelling principles within the book. To facilitate this, the ICAS-MoT modelling tool has been used. A wide range of application areas have been chosen to ensure that the principal concepts of effective and efficient modelling...... are exercised. Conceptual frameworks for single and multiscale problems are given and explained. The importance of the steps is also explained, through annotated schematic diagrams. The important issues around workflow and data flow are given in diagrammatic form....

  11. Hospital Waste Management - Case Study

    Directory of Open Access Journals (Sweden)

    Beatriz Edra

    2017-07-01

    Full Text Available The importance of waste management in hospitals is indisputable in preserving the environment and protecting public health, but management models are rarely discussed. This study presents the legal and conceptual frameworks of good waste management practices applicable to hospitals and associated indicators. As a case study, the overall performance of Hospital Centre of São João, in Porto, was analysed based on published reports. Data on the production of waste in their different typologies were collected from 2010 to 2016, enabling a correlation of the waste production with the kg/bed/day indicator. The aim of this study was to gather data and discuss trends in a real scenario of evolution over a six-year period in order to contribute to a future research proposal on indicators that can be used as reference for benchmarking the construction of methodological guides for hospital waste management.

  12. Qualitative Case Study Research as Empirical Inquiry

    Science.gov (United States)

    Ellinger, Andrea D.; McWhorter, Rochell

    2016-01-01

    This article introduces the concept of qualitative case study research as empirical inquiry. It defines and distinguishes what a case study is, the purposes, intentions, and types of case studies. It then describes how to determine if a qualitative case study is the preferred approach for conducting research. It overviews the essential steps in…

  13. A parathyroid scintigraphy case study

    International Nuclear Information System (INIS)

    O'Leary, Desiree

    2005-01-01

    Background: There has been much debate concerning the most suitable protocol for parathyroid scintigraphy; the merits of various radiopharmaceuticals versus the correct imaging protocol to visualise both ectopic and anatomically placed adenomas against the various equipment choices have been debated. Aim: To demonstrate, through the use of a case study, the necessity of changing imaging protocols for parathyroid scintigraphy where a definitive imaging diagnosis is absent in the face of strong clinical suspicion. Method: Use is made of Tc99mMIBI, full field chest scintigraphy, a clearly defined imaging protocol and SPECT imaging to locate ectopic parathyroid tissue in a female patient with significant symptoms of parathyroid hyperfunction. Results: A single hyperfunctioning adenoma is located in the pre-carinal area of the mediastinum. Using a radioguided surgical technique the hyperfunctioning tissue is excised and confirmed by histopathology. Conclusion: Whilst a dramatic reduction in patient symptoms was not seen immediately in this patient, the symptoms of the illness have been subsiding since January 2003. This case study demonstrates the necessity of changing imaging protocols for parathyroid scintigraphy where a definitive imaging diagnosis is absent in the face of strong clinical suspicion

  14. Photodynamic activity of polycyclic hydrocarbon

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, S S

    1963-01-01

    Exposure of Paramecium caudatum to suspensions of 3,4-benzopyrene, followed by long wave ultraviolet irradiation, results in cell death at times related, inter alia, to carcinogen concentration. Prior to death, the cells exhibit progressive immobilization and blebbing. This photodynamic response is a sensitized photo-oxidation, as it is oxygen-dependent and inhibited by anti-oxidants, such as butylated hydroxy anisole and ..cap alpha..-tocopherol. Protection is also afforded by other agents, including Tweens, tryptophan and certain fractions of plasma proteins. No evidence was found for the involvement of peroxides or sulfhydryl groups. The correlations between photodynamic toxicity and carcinogenicity in a large series of polycyclic hydrocarbons is under investigation. Assays of air extracts for photodynamic toxicity are in progress. Significant toxicity has been found in oxygenated besides aromatic fractions.

  15. Using Correspondence Analysis in Multiple Case Studies

    NARCIS (Netherlands)

    Kienstra, Natascha; van der Heijden, Peter G.M.

    2015-01-01

    In qualitative research of multiple case studies, Miles and Huberman proposed to summarize the separate cases in a so-called meta-matrix that consists of cases by variables. Yin discusses cross-case synthesis to study this matrix. We propose correspondence analysis (CA) as a useful tool to study

  16. Using correspondence analysis in multiple case studies

    NARCIS (Netherlands)

    Kienstra, N.H.H.; van der Heijden, P.G.M.

    2015-01-01

    In qualitative research of multiple case studies, Miles and Huberman proposed to summarize the separate cases in a so-called meta-matrix that consists of cases by variables. Yin discusses cross-case synthesis to study this matrix. We propose correspondence analysis (CA) as a useful tool to study

  17. Environmental forensic principals for sources allocation of polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    O'Sullivan, G.; Martin, E.; Sandau, C.D.

    2008-01-01

    Polycyclic aromatic hydrocarbons (PAH) are organic compounds which include only carbon and hydrogen with a fused ring structure containing at least two six-sided benzene rings but may also contain additional fused rings that are not six-sided. The environmental forensic principals for sources allocation of PAHs were examined in this presentation. Specifically, the presentation addressed the structure and physiochemical properties of PAHs; sources and sinks; fate and behaviour; analytical techniques; conventional source identification techniques; and toxic equivalent fingerprinting. It presented a case study where residents had been allegedly exposed to dioxins, PAHs and metals released from a railroad tie treatment plant. The classification of PAHs is governed by thermodynamic properties such as biogenic, petrogenic, and pyrogenic properties. A number of techniques were completed, including chemical fingerprinting; molecular diagnostic ratios; cluster analysis; principal component analysis; and TEF fingerprinting. These techniques have shown that suspected impacted sites do not all share similar PAH signatures indicating the potential for various sources. Several sites shared similar signatures to background locations. tabs., figs

  18. Polycyclic aromatic hydrocarbons (PAHs) degradation by laccase ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... Full Length Research Paper. Polycyclic aromatic ... production of paper, feeds, chemicals and fuels there is ... microbes with the production of lignin-modifying enzymes ... enable white rot fungi to degrade a variety of toxic.

  19. Case Study: A Picture Worth a Thousand Words? Making a Case for Video Case Studies

    Science.gov (United States)

    Pai, Aditi

    2014-01-01

    A picture, they say, is worth a thousand words. If a mere picture is worth a thousand words, how much more are "moving pictures" or videos worth? The author poses this not merely as a rhetorical question, but because she wishes to make a case for using videos in the traditional case study method. She recommends four main approaches of…

  20. Case studies in ultrasonic testing

    International Nuclear Information System (INIS)

    Prasad, V.; Satheesh, C.; Varde, P.V.

    2015-01-01

    Ultrasonic testing is widely used Non Destructive Testing (NDT) method and forms the essential part of In-service inspection programme of nuclear reactors. Main application of ultrasonic testing is for volumetric scanning of weld joints followed by thickness gauging of pipelines and pressure vessels. Research reactor Dhruva has completed the first In Service Inspection programme in which about 325 weld joints have been volumetrically scanned, in addition to thickness gauging of 300 meters of pipe lines of various sizes and about 24 nos of pressure vessels. Ultrasonic testing is also used for level measurements, distance measurements and cleaning and decontamination of tools. Two case studies are brought out in this paper in which ultrasonic testing is used successfully for identification of butterfly valve opening status and extent of choking in pipe lines in Dhruva reactor systems

  1. STS Case Study Development Support

    Science.gov (United States)

    Rosa de Jesus, Dan A.; Johnson, Grace K.

    2013-01-01

    The Shuttle Case Study Collection (SCSC) has been developed using lessons learned documented by NASA engineers, analysts, and contractors. The SCSC provides educators with a new tool to teach real-world engineering processes with the goal of providing unique educational materials that enhance critical thinking, decision-making and problem-solving skills. During this third phase of the project, responsibilities included: the revision of the Hyper Text Markup Language (HTML) source code to ensure all pages follow World Wide Web Consortium (W3C) standards, and the addition and edition of website content, including text, documents, and images. Basic HTML knowledge was required, as was basic knowledge of photo editing software, and training to learn how to use NASA's Content Management System for website design. The outcome of this project was its release to the public.

  2. Analysis of Polycyclic Aromatic Hydrocarbons in Ambient Aerosols by Using One-Dimensional and Comprehensive Two-Dimensional Gas Chromatography Combined with Mass Spectrometric Method: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Yun Gyong Ahn

    2018-01-01

    Full Text Available Advanced separation technology paired with mass spectrometry is an ideal method for the analysis of atmospheric samples having complex chemical compositions. Due to the huge variety of both natural and anthropogenic sources of organic compounds, simultaneous quantification and identification of organic compounds in aerosol samples represents a demanding analytical challenge. In this regard, comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS has become an effective analytical method. However, verification and validation approaches to quantify these analytes have not been critically evaluated. We compared the performance of gas chromatography with quadrupole mass spectrometry (GC-qMS and GC×GC-TOFMS for quantitative analysis of eighteen target polycyclic aromatic hydrocarbons (PAHs. The quantitative obtained results such as limits of detection (LODs, limits of quantification (LOQs, and recoveries of target PAHs were approximately equivalent based on both analytical methods. Furthermore, a larger number of analytes were consistently identified from the aerosol samples by GC×GC-TOFMS compared to GC-qMS. Our findings suggest that GC×GC-TOFMS would be widely applicable to the atmospheric and related sciences with simultaneous target and nontarget analysis in a single run.

  3. On a complete topological inverse polycyclic monoid

    Directory of Open Access Journals (Sweden)

    S. O. Bardyla

    2016-12-01

    Full Text Available We give sufficient conditions when a topological inverse $\\lambda$-polycyclic monoid $P_{\\lambda}$ is absolutely $H$-closed in the class of topological inverse semigroups. For every infinite cardinal $\\lambda$ we construct the coarsest semigroup inverse topology $\\tau_{mi}$ on $P_\\lambda$ and give an example of a topological inverse monoid $S$ which contains the polycyclic monoid $P_2$ as a dense discrete subsemigroup.

  4. Generalised Multiplicative Indices of Polycyclic Aromatic Hydrocarbons and Benzenoid Systems

    Science.gov (United States)

    Kulli, V. R.; Stone, Branden; Wang, Shaohui; Wei, Bing

    2017-05-01

    Many types of topological indices such as degree-based topological indices, distance-based topological indices, and counting-related topological indices are explored during past recent years. Among degree-based topological indices, Zagreb indices are the oldest one and studied well. In the paper, we define a generalised multiplicative version of these indices and compute exact formulas for Polycyclic Aromatic Hydrocarbons and jagged-rectangle Benzenoid systems.

  5. Carcinogenic activity of polycyclic hydrocarbons on man and animals

    Energy Technology Data Exchange (ETDEWEB)

    Shabad, L M

    1976-03-01

    Basic facts are reported on the carcinogenic activity of polycyclic aromatic hydrocarbons (PAH) towards humans and animals. Benzyprene (BP) is taken as a standard indicator for PAH. Studies of the distribution of BP in atmosphere, hydrosphere, in soil, in plants, and in animals led to an understanding of the accumulation and breakdown of this chemical. On this basis, safety limits were set as a prophylactic measure.

  6. Five Misunderstandings About Case-Study Research

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    2006-01-01

    This article examines five common misunderstandings about case-study research: (a) theoretical knowledge is more valuable than practical knowledge; (b) one cannot generalize from a single case, therefore, the single-case study cannot contribute to scientific development; (c) the case study is most...... useful for generating hypotheses, whereas other methods are more suitable for hypotheses testing and theory building; (d) the case study contains a bias toward verification; and (e) it is often difficult to summarize specific case studies. This article explains and corrects these misunderstandings one...

  7. Oxidation kinetics of polycyclic aromatic hydrocarbons by permanganate.

    Science.gov (United States)

    Forsey, Steven P; Thomson, Neil R; Barker, James F

    2010-04-01

    The reactivity of permanganate towards polycyclic aromatics hydrocarbons (PAHs) is well known but little kinetic information is available. This study investigated the oxidation kinetics of a selected group of coal tar creosote compounds and alkylbenzenes in water using permanganate, and the correlation between compound reactivity and physical/chemical properties. The oxidation of naphthalene, phenanthrene, chrysene, 1-methylnaphthalene, 2-methylnaphthalene, acenaphthene, fluorene, carbazole isopropylbenzene, ethylbenzene and methylbenzene closely followed pseudo first-order reaction kinetics. The oxidation of pyrene was initially very rapid and did not follow pseudo first-order kinetics at early times. Fluoranthene was only partially oxidized and the oxidation of anthracene was too fast to be captured. Biphenyl, dibenzofuran, benzene and tert-butylbenzene were non-reactive under the study conditions. The oxidation rate was shown to increase with increasing number of polycyclic rings because less energy is required to overcome the aromatic character of a polycyclic ring than is required for benzene. Thus the rate of oxidation increased in the series naphthalenepermanganate. 2010 Elsevier Ltd. All rights reserved.

  8. [Case-non case studies: Principles, methods, bias and interpretation].

    Science.gov (United States)

    Faillie, Jean-Luc

    2017-10-31

    Case-non case studies belongs to the methods assessing drug safety by analyzing the disproportionality of notifications of adverse drug reactions in pharmacovigilance databases. Used for the first time in the 1980s, the last few decades have seen a significant increase in the use of this design. The principle of the case-non case study is to compare drug exposure in cases of a studied adverse reaction with that of cases of other reported adverse reactions and called "non cases". Results are presented in the form of a reporting odds ratio (ROR), the interpretation of which makes it possible to identify drug safety signals. This article describes the principle of the case-non case study, the method of calculating the ROR and its confidence interval, the different modalities of analysis and how to interpret its results with regard to the advantages and limitations of this design. Copyright © 2017 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.

  9. Bacterial and human cell mutagenicity study of some C[sub 18]H[sub 10] cyclopenta-fused polycyclic aromatic hydrocarbons associated with fossil fuels combustion

    Energy Technology Data Exchange (ETDEWEB)

    Lafleur, A.L.; Longwell, J.P.; Marr, J.A.; Monchamp, P.A.; Thilly, W.G. (Massachusetts Institute of Technology, Cambridge (United States)); Mulder, P.P.Y.; Boere, B.B.; Cornelisse, J.; Lugtenburg, J. (Univ. of Leiden (Netherlands))

    1993-06-01

    A number of isomeric C[sub 18]H[sub 10] polycyclic aromatic hydrocarbons (PAHs), thought to be primarily cyclopenta-fused PAHs, are produced during the combustion and pyrolysis of fossil fuels. To determine the importance of their contributions to the total mutagenic activity of combustion and pyrolysis samples in which they are found, we characterized reference quantities of four C[sub 18]H[sub 10] CP-PAHs: benzol [ghi] fluoranthene (BF), cyclopenta [cd] pyrene (CPP), cyclopent [hi] acephenanthrylene (CPAP), and cyclopent [hi] acaenthrylene (CPAA). Synthesis of CPAA and CPAP is described. The availability of reference samples of these isomers also proved to be an essential aid in the identification of the C[sub 18]H[sub 10] species often found in combustion and pyrolysis samples. Chemical analysis of selected combustion and pyrolysis samples showed that CPP was generally the most abundant C[sub 18]H[sub 10] isomer, followed by CPAP and BF. CPAA was detected only in pyrolysis products from pure PAHs. We tested the four C[sub 18]H[sub 10] PAHs for mutagenicity in a forward mutation assay using S. typhimurium. CPP, BF, and CPAA were roughly twice as mutagenic as benzo[a]pyrene (BaP), whereas CPAP was only slightly active. These PAHs were also tested for mutagenic activity in human cells. In this assay, CPP and CPAA were strongly mutagenic but less active than BaP, whereas CPAP and BF were inactive at the dose levels tested. Also, the bacterial and human cell mutagenicity of CPAA and CPAP were compared with the mutagenicity of their monocyclopenta-fused analogs, aceanthrylene and acephenanthrylene. Although the mutagenicities of CPAP and acephenanthrylene are similar, the mutagenic activity of CPAA is an order of magnitude greater than that of aceanthrylene.

  10. Long term trends in atmospheric concentrations of polycyclic aromatic hydrocarbons and nitropolycyclic aromatic hydrocarbons: A study of Japanese cities from 1997 to 2014.

    Science.gov (United States)

    Hayakawa, Kazuichi; Tang, Ning; Nagato, Edward Gou; Toriba, Akira; Sakai, Shigekatsu; Kano, Fumio; Goto, Sumio; Endo, Osamu; Arashidani, Kei-Ichi; Kakimoto, Hitoshi

    2018-02-01

    Total suspended particulate matter (TSP) was collected during the summer and winter in five Japanese cities spanning Hokkaido to Kyushu (Sapporo, Kanazawa, Tokyo, Sagamihara and Kitakyushu) from 1997 to 2014. Nine polycyclic aromatic hydrocarbons (PAHs) with four to six rings, including pyrene (Pyr) and benzo[a]pyrene (BaP), were identified using high-performance liquid chromatography (HPLC) with fluorescence detection. Two nitropolycyclic aromatic hydrocarbons (NPAHs), 1-nitropyrene (1-NP) and 6-nitrobenzo[a]pyrene (6-NBaP), were identified by HPLC with chemiluminescence detection. A comparison of PAH and NPAH concentrations and [NPAH]/[PAH] ratios such as [1-NP]/[Pyr] and [6-NBaP]/[BaP] revealed the following characteristics in the five cities: (1) In Sapporo, Kanazawa, Tokyo and Sagamihara, the concentrations of PAHs and NPAHs were high at the beginning of the sampling period and then steadily decreased, with NPAHs decreasing faster than PAHs. The large initial [1-NP]/[Pyr] ratios suggest that the major contributor was automobiles but subsequent decreases in this ratio suggest decreased automobile contributions. (2) By contrast, PAH concentrations in Kitakyushu did not decrease during the sampling period, though concentrations of NPAHs decreased. The consistently smaller [1-NP]/[Pyr] ratio and larger [6-NBaP]/[BaP] ratio in Kitakyushu suggests that the major contributor of PAHs was not automobiles but iron manufacturing which uses a large amount of coal. The sudden increase in atmospheric PAH concentrations in the winter of 2014 may also be due to iron manufacturing. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Concentrated photovoltaics, a case study

    Directory of Open Access Journals (Sweden)

    Antonini Piergiorgio

    2014-01-01

    Full Text Available Concentrated Photovoltaics (CPV, once a niche technology, has now reached the maturity and reliability for large scale power generation. Especially in regions where temperatures are very high, the use of high efficiency triple junction solar cells with concentrating optics allows stable energy yield. Thus CPV can be seen as complementary and not in concurrence with silicon photovoltaics. The state of the art, the advantages and limitations of this technology will be shown. Among the main advantages of CPV is the possibility of a much higher energy supply, when compared to silicon photovoltaics, both comparing CPV and silicon with same area or the same installed power. The use of recycled and recyclable materials allows a more environmentally friendly production. The possibility to couple CPV with desalination facilities, energy storage will be analysed. As an example a case study of a CPV installation in Northern Italy is discussed. Here the use of mature technologies, derived from automotive and lighting sectors resulted in a simple and efficient module.

  12. Case Studies of Environmental Visualization

    Directory of Open Access Journals (Sweden)

    Panagiotis Patlakas

    2017-09-01

    Full Text Available The performance gap between simulation and reality has been identified as a major challenge to achieving sustainability in the Built Environment. While Post-Occupancy Evaluation (POE surveys are an integral part of better understanding building performance, and thus addressing this issue, the importance of POE remains relatively unacknowledged within the wider Built Environment community. A possible reason that has been highlighted is that POE survey data is not easily understood and utilizable by non-expert stakeholders, including designers. A potential method by which to address this is the visualization method, which has well established benefits for communication of big datasets. This paper presents two case studies where EnViz (short for “Environmental Visualization”, a prototype software application developed for research purposes, was utilized and its effectiveness tested via a range of analysis tasks. The results are discussed and compared with those of previous work that utilized variations of the methods presented here. The paper concludes by presenting the lessons drawn from the five-year period of EnViz, emphasizing the potential of environmental visualization for decision support in environmental design and engineering for the built environment, and suggests directions for future development.

  13. Catalog of NASA-Related Case Studies

    Data.gov (United States)

    National Aeronautics and Space Administration — The OCKO has developed over 50 case studies to enhance learning at workshops, training, retreats and conferences. Case studies make mission knowledge attractive and...

  14. a South African case study

    African Journals Online (AJOL)

    User

    learn different algorithms to solve problems, but in many cases cannot solve .... centre of Piaget‟s work is a fundamental cognitive process, which he termed ..... concept definition of continuity in calculus through collaborative instructional ...

  15. Case Study: The Chemistry of Cocaine

    Science.gov (United States)

    Dewprashad, Brahmadeo

    2011-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's case study focuses on the chemistry of cocaine to teach a number of core concepts in organic chemistry. It also requires that students read and analyze an original research paper on…

  16. Writing case studies in information systems research

    NARCIS (Netherlands)

    van der Blonk, H.C.

    Case study research can be reported in different ways. This paper explores the various ways in which researchers may choose to write down their case studies and then introduces a subsequent typology of writing case studies. The typology is based on a 2 x 2 matrix, resulting in four forms of writing

  17. Summary of case studies for cooperation mechanisms

    DEFF Research Database (Denmark)

    Longa, Francesco Dalla; Klinge Jacobsen, Henrik; Hansen, Lise-Lotte Pade

    2012-01-01

    This document is a summary report highlighting the main aspect analyzed in the RES4LESS case studies. The document starts with an introductory chapter where the background that led to the selection of the case studies is outlined. In the following three chapters the case studies are presented, hi...

  18. Determination of chlorinated polycyclic aromatic hydrocarbons in water by solid-phase extraction coupled with gas chromatography and mass spectrometry.

    Science.gov (United States)

    Wang, Xianli; Kang, Haiyan; Wu, Junfeng

    2016-05-01

    Given the potential risks of chlorinated polycyclic aromatic hydrocarbons, the analysis of their presence in water is very urgent. We have developed a novel procedure for determining chlorinated polycyclic aromatic hydrocarbons in water based on solid-phase extraction coupled with gas chromatography and mass spectrometry. The extraction parameters of solid-phase extraction were optimized in detail. Under the optimal conditions, the proposed method showed wide linear ranges (1.0-1000 ng/L) with correlation coefficients ranging from 0.9952 to 0.9998. The limits of detection and the limits of quantification were in the range of 0.015-0.591 and 0.045-1.502 ng/L, respectively. Recoveries ranged from 82.5 to 102.6% with relative standard deviations below 9.2%. The obtained method was applied successfully to the determination of chlorinated polycyclic aromatic hydrocarbons in real water samples. Most of the chlorinated polycyclic aromatic hydrocarbons were detected and 1-monochloropyrene was predominant in the studied water samples. This is the first report of chlorinated polycyclic aromatic hydrocarbons in water samples in China. The toxic equivalency quotients of chlorinated polycyclic aromatic hydrocarbons in the studied tap water were 9.95 ng the toxic equivalency quotient m(-3) . 9,10-Dichloroanthracene and 1-monochloropyrene accounted for the majority of the total toxic equivalency quotients of chlorinated polycyclic aromatic hydrocarbons in tap water. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Lymphedema during pregnancy - case study

    Directory of Open Access Journals (Sweden)

    Katarzyna Korabiusz

    2017-06-01

    Full Text Available Pregnancy is a period when woman’s body undergoes a lot of changes in her hormonal balance, lymphatic system, musculoskeletal system and cardiovascular system. As a result of disorders in defense mechanisms, a significant amount of liquid accumulates in spaces between tissues. A clinical manifestation of this condition is swelling located around ankles and lower legs. Sedentary lifestyle, unhealthy eating habits, excessive weight and pregnancy are also well known causes of lymphatic swelling. Comprehensive anti-swelling therapy that is used in treating lymphatic swelling in pregnant patients includes: patients’ education, manual lymphatic drainage, kinesitherapy, multilayer bandaging, skin care, drainage positions and kinesiotaping. Dissertation’s objective: Dissertation’s objective is to evaluate implementation of manual lymphatic drainage and anti-swelling kinesiotaping in pregnant woman with lymphatic swelling of lower legs. Research methods: Research methods were collected basing on: interview with a patient, medical documentation analysis and physical examination conduced before and after therapy. Research was conducted between 34th and 36th week of pregnancy. Case study: 38 year old patient in her fourth singleton pregnancy. Two prior pregnancies in 2009 and 2010 were delivered with C-section and one missed abortion in 2015 occurred. During this pregnancy patient gained over 30kg. She was diagnosed with lymphatic swelling of metatarsus, lower legs and ankles in 34th week of pregnancy. Lymphatic drainage of lower limbs and anti-swelling kinesiotaping was implemented. Results: After two weeks of therapy decrease in swelling was observed in left lower limb: in metatarsus by 8cm, in ankles by 9cm and in lower legs by 6cm. In right lower limb swelling decreased accordingly by 7cm, 10cm and 5cm. Conclusion: Anti-swelling lymphatic drainage, kinesiotherapy and kinesiotaping are effective physiotherapy methods used in treating lymphedema

  20. PROTONATED POLYCYCLIC AROMATIC HYDROCARBONS REVISITED

    International Nuclear Information System (INIS)

    Ricca, Alessandra; Bauschlicher, Charles W. Jr; Allamandola, Louis J.

    2011-01-01

    We reconsider the contribution that singly protonated polycyclic aromatic hydrocarbons (PAHs; HPAH + s) might make to the Class A component of the 6.2 μm interstellar emission feature in light of the recent experimental measurements of protonated naphthalene and coronene. Our calculations on the small HPAH + s have a band near 6.2 μm, as found in experiment. While the larger HPAH + s still have emission near 6.2 μm, the much larger intensity of the band near 6.3 μm overwhelms the weaker band at 6.2 μm, so that the 6.2 μm band is barely visible. Since the large PAHs are more representative of those in the interstellar medium, our work suggests that large HPAH + s cannot be major contributors to the observed emission at 6.2 μm (i.e., Class A species). Saturating large PAH cations with hydrogen atoms retains the 6.2 μm Class A band position, but the rest of the spectrum is inconsistent with observed spectra.

  1. SPHENOCHOANAL POLYP: A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Gaurav

    2015-09-01

    Full Text Available Sphenochoanal polyp is a rare clinical occurrence as compared to the much common antro - choanal polyp. It originates from the sphenoid sinus and extends into the choana via the sphenoid ostium. We present a case of spheno - choanal polyp and its clinical features and surgical management is discussed. Our aim in this case was to properly d elineate the origin of the polyp and differentiate it from other lesions such as the antro - choanal polyp and meningocele, followed by meticulous endoscopic excision of the polyp

  2. Using Case Studies to Enrich Field Experience.

    Science.gov (United States)

    Florio-Ruane, Susan; Clark, Christopher M.

    1990-01-01

    This paper discusses the use of field experience in teacher education and how it can be augmented by phenomenological case studies. It summarizes a particular case study involving three teacher education classes, noting that reflective analysis of cases can prepare students to observe in the field. (SM)

  3. Transanal rectopexy - twelve case studies

    Directory of Open Access Journals (Sweden)

    Rubens Henrique Oleques Fernandes

    2012-06-01

    Full Text Available OBJECTIVES: This study analyzed the results of transanal rectopexy and showed the benefits of this surgical technique. METHOD: Twelve patients were submitted to rectopexy between 1997 and 2011. The surgical technique used was transanal rectopexy, where the mesorectum was fixed to the sacrum with nonabsorbable suture. Three patients had been submitted to previous surgery, two by the Delorme technique and one by the Thiersch technique. RESULTS: Postoperative hospital stay ranged from 1 to 4 days. One patient (8.3% had intraoperative hematoma, which was treated with local compression and antibiotics. One patient (8.3% had residual mucosal prolapse, which was resected. Prolapse recurrence was seen in one case (8.3%. Improved incontinence occurred in 75% of patients and one patient reported obstructed evacuation in the first month after surgery. No death occurred. CONCLUSION: Transanal rectopexy is a simple, low cost technique, which has shown good efficacy in rectal prolapse control.OBJETIVO: O presente estudo analisou os resultados da retopexia pela via transanal e expôs os benefícios desta técnica cirúrgica. MÉTODO: Doze pacientes com prolapso foram operados no período de 1997 a 2011. A técnica cirúrgica usada foi a retopexia transanal, onde o mesorreto foi fixado ao sacro com fio inabsorvível. Três pacientes tinham cirurgia prévia, dois pela técnica de Delorme e um pela técnica de Thiersch. RESULTADOS: A permanência hospitalar pós-operatória variou de 1- 4 dias. Uma paciente (8,3% apresentou hematoma transoperatório que foi tratado com compressão local e antibioticoterapia. Um paciente apresentou prolapso mucoso residual (8,3%, que foi ressecado. Houve recidiva da procidência em um caso (8,3%. A melhora da incontinência ocorreu em 75% dos pacientes e uma paciente apresentou bloqueio evacuatório no primeiro mês após a cirurgia. Não houve mortalidade entre os pacientes operados. CONCLUSÃO: A retopexia transanal é uma t

  4. WP4 Case study Report

    DEFF Research Database (Denmark)

    Elle, Morten; van Gameren, Valentine; Pel, Bonno

    The INFORSE case consists of an analysis of the transnational network INFORSE (International Network for Sustainable Energy), the Danish local initiative VE and the Belgian local initiative APERe. All three are dealing with renewable energy and energy savings. The link between INFORSE and VE...

  5. Five misunderstandings about Case-study Research

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...... useful for generating hypotheses, while other methods aremore suitable for hypotheses testing and theory building; (4) The case study contains a bias toward verification; and (5) It is often difficult to summarize specific case studies. The article explains and corrects these misunderstandings one by one...... and concludes with the Kuhnian insight that a scientific discipline without a large number of thoroughly executed case studies is a discipline without systematic production of exemplars, and that a discipline without  exemplars is an ineffective one. Social science may be strengthened by the execution of more...

  6. Five misunderstandings about case study research

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    2004-01-01

    This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...... useful for generating hypotheses, while other methods aremore suitable for hypotheses testing and theory building; (4) The case study contains a bias toward verification; and (5) It is often difficult to summarize specific case studies. The article explains and corrects these misunderstandings one by one...... and concludes with the Kuhnian insight that a scientific discipline without a large number of thoroughly executed case studies is a discipline without systematic production of exemplars, and that a discipline without exemplars is an ineffective one. Social science may be strengthened by the execution of more...

  7. Drive Electric Vermont Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Fred [Energetics Incorporated, Columbia, MD (United States); Roberts, Dave [Vermont Energy Investment Corporation (VEIC), Burlington, VT (United States); Francfort, Jim [Idaho National Lab. (INL), Idaho Falls, ID (United States); White, Sera [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    Currently in the United States, the heavy majority of plug-in electric vehicle (PEV) sales have been in highly conducive, selected, metropolitan areas; opposed to more broad distribution across the country. The U.S. Department of Energy’s EV Everywhere Grand Challenge is looking carefully at the barriers and opportunities that exist to enable small and midsize communities to partake in the PEV market and benefit from the economic and environmental advantages of PEVs. In order to gain insight into these challenges and barriers, DOE selected a success story (i.e., Drive Electric Vermont) as the subject of this case study, as the state of Vermont is tied with Detroit, Michigan in having the highest percentage of 2014 (most recent complete data) PEV registrations for cold weather U.S. cities and has seen more than a sixfold increase in charging stations over the last three years. The overall objective of this case study was to use the lessons learned from Drive Electric Vermont to determine what activities are most effective at encouraging acquisitions of PEVs and deployment of charging infrastructure in small to midsize communities, prioritizing and sequencing their implementation, identifying robust means for extrapolation, and applying this understanding to other small to midsize communities across the nation. The Drive Electric Vermont Program was formed in 2012 with a goal of increasing the use of electrified transportation in Vermont through policy development, education and outreach, and infrastructure development. The Drive Electric Vermont Program can be broadly broken into four components: (1) strategic planning/leadership, (2) stakeholder/partnership development, (3) education and outreach, and (4) incentives. The early phases of the program focused heavily on strategic planning, and stakeholder and partnership development, followed by a transition to education and outreach activities, charging infrastructure development, and grant and incentive programs

  8. Research Progress of Polycyclic Polyprenylated Acylphloroglucinols.

    Science.gov (United States)

    Yang, Xing-Wei; Grossman, Robert B; Xu, Gang

    2018-04-11

    Polycyclic polyprenylated acylphloroglucinols (PPAPs) are a class of hybrid natural products sharing the mevalonate/methylerythritol phosphate and polyketide biosynthetic pathways and showing considerable structure and bioactivity diversity. This review discusses the progress of research into the chemistry and biological activity of 421 natural PPAPs in the past 11 years as well as in-depth studies of biological activities and total synthesis of some PPAPs isolated before 2006. We created an online database of all PPAPs known to date at http://www.chem.uky.edu/research/grossman/PPAPs . Two subclasses of biosynthetically related metabolites, spirocyclic PPAPs with octahydrospiro[cyclohexan-1,5'-indene]-2,4,6-trione core and complicated PPAPs produced by intramolecular [4 + 2] cycloadditions of MPAPs, are brought into the PPAP family. Some PPAPs' relative or absolute configurations are reassigned or critically discussed, and the confusing trivial names in PPAPs investigations are clarified. Pharmacologic studies have revealed a new molecular mechanism whereby hyperforin and its derivatives regulate neurotransmitter levels by activating TRPC6 as well as the antitumor mechanism of garcinol and its analogues. The antineoplastic potential of some type B PPAPs such as oblongifolin C and guttiferone K has increased significantly. As a result of the recent appearances of innovative synthetic methods and strategies, the total syntheses of 22 natural PPAPs including hyperforin, garcinol, and plukenetione A have been accomplished.

  9. POLYCYCLIC AROMATIC HYDROCARBON CONTAMINATION LEVELS IN COLLECTED SAMPLES FROM VICINITY OF A HIGHWAY

    Directory of Open Access Journals (Sweden)

    S. V. Samimi ، R. Akbari Rad ، F. Ghanizadeh

    2009-01-01

    Full Text Available Tehran as the biggest city of Iran with a population of more than 10 millions has potentially high pollutant exposures of gas oil and gasoline combustion from vehicles that are commuting in the highways every day. The vehicle exhausts contain polycyclic aromatic hydrocarbons, which are produced by incomplete combustion and can be directly deposited in the environment. In the present study, the presence of polycyclic aromatic hydrocarbons contamination in the collected samples of a western highway in Tehran was investigated. The studied location was a busy highway in Tehran. High performance liquid chromatography equipped with florescence detector was used for determination of polycyclic aromatic hydrocarbons concentrations in the studied samples. Total concentration of the ten studied polycyclic aromatic hydrocarbons compounds ranged from 11107 to 24342 ng/g dry weight in the dust samples and increased from 164 to 2886 ng/g dry weight in the soil samples taken from 300 m and middle of the highway, respectively. Also the average of Σ PAHs was 1759 ng/L in the water samples of pools in parks near the highway. The obtained results indicated that polycyclic aromatic hydrocarbons contamination levels were very high in the vicinity of the highway.

  10. The use of cork waste as a biosorbent for persistent organic pollutants-Study of adsorption/desorption of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Olivella, Maria À; Jové, Patrícia; Oliveras, Anna

    2011-01-01

    The aim of this study is to determine the sorption-desorption behavior of a mixture of thirteen aqueous PAHs on cork waste at a particle of size 0.25-0.42 mm obtained from the remains of cork strips. The final purpose is to use this natural adsorbent as an alternative to activated carbon in an innovative approach for the removal of this class of toxic compounds, and significantly reduce the regeneration costs of the process. The chemical composition of the selected cork revealed that suberin (38.5 %) and lignin (31.6 %) were the main structural components of the cell wall. The high efficiency of cork as a biosorbent of PAHs is shown by the fact that just over 80 % of adsorption occurred during the first two minutes of contact time. Both Freundlich's and Langmuir's isotherms gave good fits to the sorption process. The highest adsorption affinities were exhibited for pyrene, anthracene, and phenanthrene. Desorption studies indicate a high degree of irreversibility for all PAHs, and especially so in the case of high molecular PAHs. The correlation with K(F) and low molecular weight PAHs was the most significant. The quantity of cork required to reduce water pollution was estimated to be between 3 and 15 times less than the quantities required in the case of other materials (i.e. aspen wood and leonardite). This study demonstrates for the first time that cork is a potential biosorbent for PAHs and may have relevance in the future treatment of PAH-contaminated waters.

  11. Roadmaster Roading Contractors Case Study

    Directory of Open Access Journals (Sweden)

    Hazel Taylor

    1999-01-01

    Full Text Available Systems analysis students seldom experience the practical difficulties of the initial investigation into a client’s requirements. They get little chance to practice the skills they need to investigate complex and confused problem situations, or to appreciate the wider organizational issues that can impact on a situation. This teaching case is designed to give students the opportunity to practice and apply investigation skills and to challenge them to consider the wider work environment when considering possible solutions to a problem situation. The case is conducted as a role-play, with students acting as systems analysts and teaching staff role-playing the clients. The students develop a report analyzing the client’s situation based on the issues that arise during the interviews. Feed-back sessions focus on discussing how well the students applied various interviewing strategies previously covered in lectures, and on the wider organizational problems that could impact proposed information system solutions.

  12. Bioremediation case studies: Abstracts. Final report

    International Nuclear Information System (INIS)

    Devine, K.

    1992-03-01

    The report contains abstracts of 132 case studies of bioremediation technology applied to hazardous waste clean-up. It was prepared to compile bioremediation studies in a variety of locations and treating diverse contaminants, most of which were previously undocumented. All data are based on vendor-supplied information and there was no opportunity to independently confirm its accuracy. These 132 case studies, from 10 different biotechnology companies, provide users with reference information about on-going and/or completed field applications and studies. About two-thirds of the cases were at full-scale clean-up level with the remainder at pilot or laboratory scale. In 74 percent of the cases, soil was at least one of the media treated. Soil alone accounts for 46 percent of the cases. Petroleum-related wastes account for the largest contaminant with 82 cases. Thirty-one states are represented in the case studies

  13. Polycyclic Aromatic Hydrocarbons in Fine Particulate Matter Emitted from Burning Kerosene, Liquid Petroleum Gas, and Wood Fuels in Household Cookstoves

    Science.gov (United States)

    This study measured polycyclic aromatic hydrocarbon (PAH) composition in particulate matter emissions from residential cookstoves. A variety of fuel and cookstove combinations were examined, including: (i) liquid petroleum gas (LPG), (ii) kerosene in a wick stove, (iii) wood (10%...

  14. Porphyrins Fused with Unactivated Polycyclic Aromatic Hydrocarbons

    KAUST Repository

    Diev, Vyacheslav V.; Schlenker, Cody W.; Hanson, Kenneth; Zhong, Qiwen; Zimmerman, Jeramy D.; Forrest, Stephen R.; Thompson, Mark E.

    2012-01-01

    A systematic study of the preparation of porphyrins with extended conjugation by meso,β-fusion with polycyclic aromatic hydrocarbons (PAHs) is reported. The meso-positions of 5,15-unsubstituted porphyrins were readily functionalized with PAHs. Ring fusion using standard Scholl reaction conditions (FeCl 3, dichloromethane) occurs for perylene-substituted porphyrins to give a porphyrin β,meso annulated with perylene rings (0.7:1 ratio of syn and anti isomers). The naphthalene, pyrene, and coronene derivatives do not react under Scholl conditions but are fused using thermal cyclodehydrogenation at high temperatures, giving mixtures of syn and anti isomers of the meso,β-fused porphyrins. For pyrenyl-substituted porphyrins, a thermal method gives synthetically acceptable yields (>30%). Absorption spectra of the fused porphyrins undergo a progressive bathochromic shift in a series of naphthyl (λ max = 730 nm), coronenyl (λ max = 780 nm), pyrenyl (λ max = 815 nm), and perylenyl (λ max = 900 nm) annulated porphyrins. Despite being conjugated with unsubstituted fused PAHs, the β,meso-fused porphyrins are more soluble and processable than the parent nonfused precursors. Pyrenyl-fused porphyrins exhibit strong fluorescence in the near-infrared (NIR) spectral region, with a progressive improvement in luminescent efficiency (up to 13% with λ max = 829 nm) with increasing degree of fusion. Fused pyrenyl-porphyrins have been used as broadband absorption donor materials in photovoltaic cells, leading to devices that show comparatively high photovoltaic efficiencies. © 2011 American Chemical Society.

  15. Porphyrins Fused with Unactivated Polycyclic Aromatic Hydrocarbons

    KAUST Repository

    Diev, Vyacheslav V.

    2012-01-06

    A systematic study of the preparation of porphyrins with extended conjugation by meso,β-fusion with polycyclic aromatic hydrocarbons (PAHs) is reported. The meso-positions of 5,15-unsubstituted porphyrins were readily functionalized with PAHs. Ring fusion using standard Scholl reaction conditions (FeCl 3, dichloromethane) occurs for perylene-substituted porphyrins to give a porphyrin β,meso annulated with perylene rings (0.7:1 ratio of syn and anti isomers). The naphthalene, pyrene, and coronene derivatives do not react under Scholl conditions but are fused using thermal cyclodehydrogenation at high temperatures, giving mixtures of syn and anti isomers of the meso,β-fused porphyrins. For pyrenyl-substituted porphyrins, a thermal method gives synthetically acceptable yields (>30%). Absorption spectra of the fused porphyrins undergo a progressive bathochromic shift in a series of naphthyl (λ max = 730 nm), coronenyl (λ max = 780 nm), pyrenyl (λ max = 815 nm), and perylenyl (λ max = 900 nm) annulated porphyrins. Despite being conjugated with unsubstituted fused PAHs, the β,meso-fused porphyrins are more soluble and processable than the parent nonfused precursors. Pyrenyl-fused porphyrins exhibit strong fluorescence in the near-infrared (NIR) spectral region, with a progressive improvement in luminescent efficiency (up to 13% with λ max = 829 nm) with increasing degree of fusion. Fused pyrenyl-porphyrins have been used as broadband absorption donor materials in photovoltaic cells, leading to devices that show comparatively high photovoltaic efficiencies. © 2011 American Chemical Society.

  16. Liverpool Telecare Pilot: case studies

    Directory of Open Access Journals (Sweden)

    Nigel Barnes

    2006-09-01

    Full Text Available Telecare services use information and communications technology (ICT to support the provision of care to people in their own homes. This paper describes a pilot telecare service employed by Liverpool (UK City Council to support a sample of their frail and elderly social services users. The pilot has been running for over two years and has been deployed for 21 individuals in Liverpool. In this paper we present the pilot system and provide real example cases which help to illustrate the benefits of such a system.

  17. Associative Visual Agnosia: A Case Study

    OpenAIRE

    Charnallet, A.; Carbonnel, S.; David, D.; Moreaud, O.

    2008-01-01

    We report a case of massive associative visual agnosia. In the light of current theories of identification and semantic knowledge organization, a deficit involving both levels of structural description system and visual semantics must be assumed to explain the case. We suggest, in line with a previous case study [1], an alternative account in the framework of (non abstractive) episodic models of memory [4].

  18. Associative visual agnosia: a case study.

    Science.gov (United States)

    Charnallet, A; Carbonnel, S; David, D; Moreaud, O

    2008-01-01

    We report a case of massive associative visual agnosia. In the light of current theories of identification and semantic knowledge organization, a deficit involving both levels of structural description system and visual semantics must be assumed to explain the case. We suggest, in line with a previous case study, an alternative account in the framework of (non abstractive) episodic models of memory.

  19. Study on Case Teaching of Financial Management

    Science.gov (United States)

    Che, Zhenghong; Che, Zhengmei

    2011-01-01

    Case teaching is an efficient teaching method of management. It plays an important role to enhance the students' ability to practice the theory. However, case teaching of financial management has not achieved the expected results. The paper aims to study the importance, characteristics and corresponding methods of case teaching method of financial…

  20. Determination of polycyclic aromatic hydrocarbons in airborne

    International Nuclear Information System (INIS)

    Pachon Q, Jorge; Garcia L, Hector; Bustos L, Martha; Bravo A, Humberto; Sosa E, Rodolfo

    2004-01-01

    Rainfall polycyclic aromatic hydrocarbons (PAH) concentrations were determined in particulate matter with a <10 mm aerodynamic diameter (PM10) in three industrial municipalities of the metropolitan zone of Bogota City (MZBC). The 12 samples of greatest concentration of PM10 collected between 2001 and 2002 at the stations of atmospheric monitoring of Cundinamarca secretary of health (SSC), in the municipalities of Soacha, Sibate and Cajica, were analyzed. The results were correlated with emissions in the area, by means of emission factors and environmental agencies information. The particulate matter results for the analyzed period show concentrations that exceed the air quality standard of the US environmental protection agency EPA on several occasions at the Soacha municipality, whereas the air quality in the Sibate and Cajica municipalities did not show that to be the case. Despite the reduced number of samples and sampling sites, we believe that the reported profiles can be considered a valid estimation of the average air quality of the MZBC. The identified PAH species were: phenanthrene(Phe), anthracene(Ant), fluoranthene(Fla), pyrene(Pyr), benzo(a)anthracene (Baa), chrysene(chr), benzo(ghi)perylene(BgP) and indeno(1,2,3-cd)pyrene(Ind). It was not possible to quantify naphthalene (Nap), acenaphthy-lene(Acy), acenaphthene(Ace), nor fluorene(Flu), being light and volatile hydrocarbons with greater presence in the gaseous phase of the air. The correlation of PAH with source emissions shows mobile sources to be the main origin. The intervals of concentration of both individual PAH and the total species were similar to the ones usually found in other industrial zones of the world. PAHs correlations allowed pinpointing common emission sources between Soacha and Sibate municipalities

  1. Case Study of the NENE Code Project

    National Research Council Canada - National Science Library

    Kendall, Richard; Post, Douglass; Mark, Andrew

    2007-01-01

    ...) Program is sponsoring a series of case studies to identify the life cycles, workflows, and technical challenges of computational science and engineering code development that are representative...

  2. How To Set Up Your Own Small Business. Service Company Case Study. Manufacturing Firm Case Study. Retail Store Case Study.

    Science.gov (United States)

    Fallek, Max

    This collection of case studies is intended for use in a course in setting up a small business. The first, a case study of the process of setting up a service company, covers analyzing the pros and cons of starting one's own business, assessing the competition and local market, and selecting a site for and financing the business. The principal…

  3. Optimization and determination of polycyclic aromatic hydrocarbons in biochar-based fertilizers.

    Science.gov (United States)

    Chen, Ping; Zhou, Hui; Gan, Jay; Sun, Mingxing; Shang, Guofeng; Liu, Liang; Shen, Guoqing

    2015-03-01

    The agronomic benefit of biochar has attracted widespread attention to biochar-based fertilizers. However, the inevitable presence of polycyclic aromatic hydrocarbons in biochar is a matter of concern because of the health and ecological risks of these compounds. The strong adsorption of polycyclic aromatic hydrocarbons to biochar complicates their analysis and extraction from biochar-based fertilizers. In this study, we optimized and validated a method for determining the 16 priority polycyclic aromatic hydrocarbons in biochar-based fertilizers. Results showed that accelerated solvent extraction exhibited high extraction efficiency. Based on a Box-Behnken design with a triplicate central point, accelerated solvent extraction was used under the following optimal operational conditions: extraction temperature of 78°C, extraction time of 17 min, and two static cycles. The optimized method was validated by assessing the linearity of analysis, limit of detection, limit of quantification, recovery, and application to real samples. The results showed that the 16 polycyclic aromatic hydrocarbons exhibited good linearity, with a correlation coefficient of 0.996. The limits of detection varied between 0.001 (phenanthrene) and 0.021 mg/g (benzo[ghi]perylene), and the limits of quantification varied between 0.004 (phenanthrene) and 0.069 mg/g (benzo[ghi]perylene). The relative recoveries of the 16 polycyclic aromatic hydrocarbons were 70.26-102.99%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Case studies in conservation science

    Science.gov (United States)

    Bisulca, Christina

    The research presented in this dissertation covers three separate topics of conservation as defined by the National Science Foundation: 1) Materials Stabilization, Strengthening, Monitoring, and Repair; 2. Understanding Material Degradation and Aging; and 3) Materials and Structural Characterization of Cultural Heritage Objects (the 'technical study'). The first topic is addressed through a study to assess the consolidant tetraethoxysilane for the stabilization of alum treated wood. Falling under materials degradation studies is a study published in American Museum Novitates to understand how environmental conditions affect the aging of fossil resins from five different deposits. Two separate studies are included in technical study of cultural heritage objects which comprises the third research area of materials characterization. The first is a survey of red dyes used in Chinese paintings from the Ming Dynasty to the Early Republic (1364-1911). The second is a study of the pigments, dyes and binders used in Hawaiian barkcloth (kapa) from the 19th century.

  5. Identifying specific interstellar polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Mulas, Giacomo; Malloci, Giuliano; Porceddu, Ignazio

    2005-01-01

    Interstellar Polycyclic Aromatic Hydrocarbons (PAHs) have been thought to be ubiquitous for more than twenty years, yet no single species in this class has been identified in the Interstellar Medium (ISM) to date. The unprecedented sensitivity and resolution of present Infrared Space Observatory (ISO) and forthcoming Herschel observations in the far infrared spectral range will offer a unique way out of this embarrassing impasse

  6. Toxic Potential of Carcinogenic Polycyclic Aromatic Hydrocarbons ...

    African Journals Online (AJOL)

    Toxic Potential of Carcinogenic Polycyclic Aromatic Hydrocarbons (cPAHs) and Heavy Metal in Crude Oil from Gokana Area, Rivers State, Nigeria. ... Considerable caution should be applied in exploration, exposure and distribution of the crude oil through protected and well maintained pipelines to avoid the possible ...

  7. Polycyclic Aromatic Hydrocarbons (PAHs) Levels in Two ...

    African Journals Online (AJOL)

    Polycyclic aromatic hydrocarbons (PAHs) concentrations were measured by gas chromatography with flame ionization detector (GC/FID) in two fish species, Sardinella maderensis (Flat sardinella) and Galeoides decadactylus (Lesser African threadfin or Shine-nose or Common threadfin) from Ghanaian coastal waters and ...

  8. 6 Polycyclic Aromatic Hydrocarbons.cdr

    African Journals Online (AJOL)

    Administrator

    mutations and birth defects (Zedec, 1980;. White, 1986). ... include the use of creosote-treated wood in. Polycyclic ... concentrations of PAHs ranged from below detection limit of 0.01 µg/kg wet wt to 34.04 ± 0.56 µg/kg wet wt in S. maderensis ...

  9. Determination of carcinogenic polycyclic aromatic hydrocarbons ...

    African Journals Online (AJOL)

    Log in or Register to get access to full text downloads. ... collected from the most polluted part of Bangsai river at Saver industrial zone was analyzed for the presence of polycyclic aromatic hydrocarbon, anthracene, by gas chromatography-mass spectrometry (GC-MS). A ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  10. Forms of polycyclic aromatic hydrocarbon in the formation of sewage sludge toxicity to Heterocypris incongruens

    International Nuclear Information System (INIS)

    Oleszczuk, Patryk

    2008-01-01

    The aim of the present study was to evaluate to what degree polycyclic aromatic hydrocarbon (PAH) determines sewage sludge toxicity in relation to Heterocypris incongruens. Six differing sewage sludges with increasing contents of polycyclic aromatic hydrocarbons were selected for the present study. As well as total PAH content, the content of the potentially bioavailable fraction was also determined in the sewage sludges using a method of mild-solvent extraction (with n-butanol). The PAH content was also calculated in the sewage sludge pore water by the equilibrium partitioning method. The total PAH content in the sewage sludges studied were in the range 3.60 to 27.95 mg kg -1 . The contribution of the n-butanol extracted fraction was in the range 38.7 to 75.4%. In the group of individual PAHs, 4- and 5-ring compounds had the highest content in the potentially bioavailable group. H. incongruens mortality in the range 6.7 to 100%, depending both on the sewage sludge and the dose applied. An increase of the sewage sludge dose usually resulted in an increase in toxicity. At the highest dose, a 100% mortality of H. incongruens was found in half of the sludges. The lowest dose, irrespective of the sludge type, caused over 40% growth inhibition. However, the results obtained did not allow for the establishing of an unambiguous relationship between various sludge toxicity levels and the content of potentially bio-available PAHs. In some cases only, the extraction using n-butanol explained the high difference in toxicity despite a slight differentiation in the PAH content

  11. Using Case Studies to Teach Courtesy Strategies.

    Science.gov (United States)

    Moore, Patrick

    1990-01-01

    Explains some courtesy techniques that technical professionals can use to deal with interpersonal problems that arise in writing situations. Presents three case studies with sample responses to show how case studies can teach these courtesy strategies to technical writing students. (MM)

  12. A Comparative Comment on the Case Studies

    DEFF Research Database (Denmark)

    Kjeldsen, Christian Christrup; Ley, Thomas; Jensen, Niels Rosendal

    2012-01-01

    Denne konklusion sammenfatter hovedtrækkene af de gennemførte case studies i WorkAble-projektet. Vigtige pointer er, at unge på tværs af de forskellige case studies har vanskeligt ved at blive hørt og taget alvorligt. I stedet spises de af med "realistisk vejledning" eller dårlige uddannelses- og...

  13. Reverse logistics: A review of case studies

    NARCIS (Netherlands)

    Brito, de M.P.; Dekker, Rommert; Flapper, S.D.P.; Fleischmann, B.; Klose, A.

    2004-01-01

    This paper gives an overview of scientific literature that describes and discusses cases of reverse logistics activities in practice. Over sixty case studies are considered. Based on these studies we are able to indicate critical factors for the practice of reverse logistics. In addition we compare

  14. A Case Study of "Empathetic Teaching Artistry"

    Science.gov (United States)

    Risner, Doug

    2014-01-01

    This case study is one of twenty cases derived from Anderson and Risner's international study of teaching artists in dance, and theatre, which investigated participants' (n=172) artistic and academic preparation in dance, and theatre, initial entry into the teaching artist field, rewards, challenges, and obstacles in participants' work, artists'…

  15. The Danish National Case Study Report

    DEFF Research Database (Denmark)

    Brodersen, Søsser; Jørgensen, Michael Søgaard

    Three case studies from Danish science shops within the environmental field are analysed with respect to societal background, interaction between the involved actors and the societal impact of the co-operation. The report is one of the seven national case study reports from the EU...

  16. Outage management: A case study

    International Nuclear Information System (INIS)

    Haber, S.B.; Barriere, M.T.; Roberts, K.H.

    1992-01-01

    Outage management issues identified from a field study conducted at a two-unit commercial pressurized water reactor (PWR), when one unit was in a refueling outage and the other unit was at full power operation, are the focus of this paper. The study was conduced as part of the US Nuclear Regulatory Commission's (NRC) organizational factors research program, and therefore the issues to be addressed are from an organizational perspective. Topics discussed refer to areas identified by the NRC as critical for safety during shutdown operations, including outage planning and control, personnel stress, and improvements in training and procedures. Specifically, issues in communication, management attention, involvement and oversight, administrative processes, organizational culture, and human resources relevant to each of the areas are highlighted by example from field data collection. Insights regarding future guidance in these areas are presented based upon additional data collection subsequent to the original study

  17. Five case studies of multifamily weatherization programs

    Energy Technology Data Exchange (ETDEWEB)

    Kinney, L; Wilson, T.; Lewis, G. [Synertech Systems Corp. (United States); MacDonald, M. [Oak Ridge National Lab., TN (United States)

    1997-12-31

    The multifamily case studies that are the subject of this report were conducted to provide a better understanding of the approach taken by program operators in weatherizing large buildings. Because of significant variations in building construction and energy systems across the country, five states were selected based on their high level of multifamily weatherization. This report summarizes findings from case studies conducted by multifamily weatherization operations in five cities. The case studies were conducted between January and November 1994. Each of the case studies involved extensive interviews with the staff of weatherization subgrantees conducting multifamily weatherization, the inspection of 4 to 12 buildings weatherized between 1991 and 1993, and the analysis of savings and costs. The case studies focused on innovative techniques which appear to work well.

  18. A case study of Douala

    Indian Academy of Sciences (India)

    In this paper, demand of energy (heating/cooling) in the buildings is discussed in Douala, Cameroon. Daily data of the last 40 years coming from five weather stations of Cameroon have been studied. Some forecasts have been carried out with 14 GCM models, associated to three future climate scenarios B1, A2, and A1B.

  19. A chromite ore case study

    African Journals Online (AJOL)

    2009-05-15

    May 15, 2009 ... of Cr(VI). If this is true, it could have serious consequences for South African chromite mines and the local environment. ... study proved that the Cr(VI) content of chromite samples is .... used during pulvizising experiments was dried at 40ºC for 1 d ... This is the simplest Cr(VI) extraction method and is similar.

  20. Case Study on Quality Education

    Science.gov (United States)

    Habib, Zahida

    2011-01-01

    Quality of Education, especially at Primary level, is an important issue to be discussed at the International Forum. This study highlights the quality of primary education through a comparison of the quality of Community Model Schools and Govt. Girls Primary Schools in Pakistan. Community Model Schools were established under Girls Primary…

  1. Theoretical pluralism in psychoanalytic case studies.

    Science.gov (United States)

    Willemsen, Jochem; Cornelis, Shana; Geerardyn, Filip M; Desmet, Mattias; Meganck, Reitske; Inslegers, Ruth; Cauwe, Joachim M B D

    2015-01-01

    The aim of this study is to provide an overview of the scientific activity of different psychoanalytic schools of thought in terms of the content and production of case studies published on ISI Web of Knowledge. Between March 2013 and November 2013, we contacted all case study authors included in the online archive of psychoanalytic and psychodynamic case studies (www.singlecasearchive.com) to inquire about their psychoanalytic orientation during their work with the patient. The response rate for this study was 45%. It appears that the two oldest psychoanalytic schools, Object-relations psychoanalysis and Ego psychology or "Classical psychoanalysis" dominate the literature of published case studies. However, most authors stated that they feel attached to two or more psychoanalytic schools of thought. This confirms that the theoretical pluralism in psychoanalysis stretches to the field of single case studies. The single case studies of each psychoanalytic school are described separately in terms of methodology, patient, therapist, or treatment features. We conclude that published case studies features are fairly similar across different psychoanalytic schools. The results of this study are not representative of all psychoanalytic schools, as some do not publish their work in ISI ranked journals.

  2. Theoretical pluralism in psychoanalytic case studies

    Science.gov (United States)

    Willemsen, Jochem; Cornelis, Shana; Geerardyn, Filip M.; Desmet, Mattias; Meganck, Reitske; Inslegers, Ruth; Cauwe, Joachim M. B. D.

    2015-01-01

    The aim of this study is to provide an overview of the scientific activity of different psychoanalytic schools of thought in terms of the content and production of case studies published on ISI Web of Knowledge. Between March 2013 and November 2013, we contacted all case study authors included in the online archive of psychoanalytic and psychodynamic case studies (www.singlecasearchive.com) to inquire about their psychoanalytic orientation during their work with the patient. The response rate for this study was 45%. It appears that the two oldest psychoanalytic schools, Object-relations psychoanalysis and Ego psychology or “Classical psychoanalysis” dominate the literature of published case studies. However, most authors stated that they feel attached to two or more psychoanalytic schools of thought. This confirms that the theoretical pluralism in psychoanalysis stretches to the field of single case studies. The single case studies of each psychoanalytic school are described separately in terms of methodology, patient, therapist, or treatment features. We conclude that published case studies features are fairly similar across different psychoanalytic schools. The results of this study are not representative of all psychoanalytic schools, as some do not publish their work in ISI ranked journals. PMID:26483725

  3. Making a case for case studies in psychotherapy training

    DEFF Research Database (Denmark)

    Mackrill, Thomas Edward; Iwakabe, Shigeru

    2013-01-01

    articulated explicitly or researched systematically in spite of its cardinal importance. An analysis of the role of case studies in psychotherapy training is presented. Reading, watching, or hearing about cases can offer novice psychotherapists access to a closed world; access to psychological theory...... in action; access to whole courses of therapy; access to different approaches; access to significant moments; access to the therapeutic relationship; access to a wide range of client types; access to working in different contexts; and the opportunity of identifying with therapists and clients. Writing...

  4. Arctic bioremediation -- A case study

    International Nuclear Information System (INIS)

    Smallbeck, D.R.; Ramert, P.C.; Liddell, B.V.

    1994-01-01

    This paper discusses the use of bioremediation as an effective method to clean up diesel-range hydrocarbon spills in northern latitudes. The results of a laboratory study of microbial degradation of hydrocarbons under simulated arctic conditions showed that bioremediation can be effective in cold climates and led to the implementation of a large-scale field program. The results of 3 years of field testing have led to a significant reduction in diesel-range hydrocarbon concentrations in the contaminated area

  5. Polycyclic aromatic hydrocarbons, tobacco smoke, and epigenetic remodeling in asthma

    Science.gov (United States)

    Klingbeil, E. C.; Hew, K. M.; Nygaard, U. C.; Nadeau, K. C.

    2014-01-01

    Environmental determinants including aerosolized pollutants such as polycyclic aromatic hydrocarbons (PAHs) and tobacco smoke have been associated with exacerbation and increased incidence of asthma. The influence of aerosolized pollutants on the development of immune dysfunction in asthmatics has been suggested to be mediated through epigenetic remodeling. Genome accessibility and transcription are regulated primarily through DNA methylation, histone modification, and microRNA transcript silencing. Epigenetic remodeling has been shown in studies to be associated with Th2 polarization and associated cytokine and chemokine regulation in the development of asthma. This review will present evidence for the contribution of the aerosolized pollutants PAH and environmental tobacco smoke to epigenetic remodeling in asthma. PMID:24760221

  6. Schematic representation of case study research designs.

    Science.gov (United States)

    Rosenberg, John P; Yates, Patsy M

    2007-11-01

    The paper is a report of a study to demonstrate how the use of schematics can provide procedural clarity and promote rigour in the conduct of case study research. Case study research is a methodologically flexible approach to research design that focuses on a particular case - whether an individual, a collective or a phenomenon of interest. It is known as the 'study of the particular' for its thorough investigation of particular, real-life situations and is gaining increased attention in nursing and social research. However, the methodological flexibility it offers can leave the novice researcher uncertain of suitable procedural steps required to ensure methodological rigour. This article provides a real example of a case study research design that utilizes schematic representation drawn from a doctoral study of the integration of health promotion principles and practices into a palliative care organization. The issues discussed are: (1) the definition and application of case study research design; (2) the application of schematics in research; (3) the procedural steps and their contribution to the maintenance of rigour; and (4) the benefits and risks of schematics in case study research. The inclusion of visual representations of design with accompanying explanatory text is recommended in reporting case study research methods.

  7. Oxidation kinetics of polycyclic aromatic hydrocarbons by permanganate

    Energy Technology Data Exchange (ETDEWEB)

    Forsey, S.P.; Thomson, N.R.; Barker, J.F. [University of Waterloo, Waterloo, ON (Canada). Dept. of Civil & Environmental Engineering

    2010-04-15

    The reactivity of permanganate towards polycyclic aromatics hydrocarbons (PAHs) is well known but little kinetic information is available. This study investigated the oxidation kinetics of a selected group of coal tar creosote compounds and alkylbenzenes in water using permanganate, and the correlation between compound reactivity and physical/chemical properties. The oxidation of naphthalene, phenanthrene, chrysene, 1-methylnaphthalene, 2-methylnaphthalene, acenaphthene, fluorene, carbazole isopropylbenzene, ethylbenzene and methylbenzene closely followed pseudo first-order reaction kinetics. The oxidation of pyrene was initially very rapid and did not follow pseudo first-order kinetics at early times. Fluoranthene was only partially oxidized and the oxidation of anthracene was too fast to be captured. Biphenyl, dibenzofuran, benzene and tert-butylbenzene were non-reactive under the study conditions. The oxidation rate was shown to increase with increasing number of polycyclic rings because less energy is required to overcome the aromatic character of a polycyclic ring than is required for benzene. Thus the rate of oxidation increased in the series naphthalene < phenanthrene < pyrene. The rate of side chain reactivity is controlled by the C-H bond strength. For the alkyl substituted benzenes an excellent correlation was observed between the reaction rate coefficients and bond dissociation energies, but for the substituted PAHs the relationship was poor. A trend was found between the reaction rate coefficients and the calculated heats of complexation indicating that significant ring oxidation occurred in addition to side chain oxidation. Clar's aromatic sextet theory was used to predict the relative stability of arenes towards ring oxidation by permanganate.

  8. Associative Visual Agnosia: A Case Study

    Directory of Open Access Journals (Sweden)

    A. Charnallet

    2008-01-01

    Full Text Available We report a case of massive associative visual agnosia. In the light of current theories of identification and semantic knowledge organization, a deficit involving both levels of structural description system and visual semantics must be assumed to explain the case. We suggest, in line with a previous case study [1], an alternative account in the framework of (non abstractive episodic models of memory [4].

  9. Case Study Methodology and Homelessness Research

    Directory of Open Access Journals (Sweden)

    Jill Pable

    2013-10-01

    Full Text Available This paper describes the potential suitability of case study methodology for inquiry with the homeless population. It references a research study that uses case study research method to build theory. This study's topic is the lived experience of destitute individuals who reside in homeless shelters, and explores the homeless shelter built environment's potential influence on resident satisfaction and recovery. Case study methodology may be appropriate because it explores real-life contextual issues that characterize homelessness and can also accommodate the wide range of homeless person demographics that make this group difficult to study in a generalized fashion. Further, case study method accommodates the need within research in this area to understand individualized treatments as a potential solution for homelessness.

  10. INTERIORITY - a prefab case study

    DEFF Research Database (Denmark)

    Hvejsel, Marie Frier

    Dealing with the general theme of domestic architectural quality, the PhD thesis ‘INTERIORITY’ takes its point of departure in the continuous and increasing need to improve our capability as architects to theoretically articulate the intangible concept of quality, and to reveal it through an active...... been motivated by the particular hypothesis that an introduction of the notion of interiority, as an ability of the spatial envelope itself to address the sensuous scale of furniture, unfolds a particular dual critical potential signifying our experience of domestic architectural quality: On the one......, tectonically. Hence, it has been a particular idea of the study to explore the relation between furniture, the spatial envelope itself, and its construct by using furniture as an architectural concept. Consequently, the thesis has specifically investigated whether this notion of interiority, describing...

  11. Case study on printed matter

    DEFF Research Database (Denmark)

    – how important are emissions of chemicals? J Clean Prod 17, 115 – 128. Larsen HF (2004). Assessment of chemical emissions in life cycle impact assessment - focus on low substance data availability and ecotoxicity effect indicators. Ph.D. Thesis, October 2004. Department of Manufacturing, Engineering...... and Management. Technical University of Denmark. http://www.tempo.ipl.dtu.dk/ipl/upload/publ/PhD-thesis-rev.pdf Figure 1 Comparison of weighted LCA profiles with or without chemical related impact categories included (percentage of total, milli-person-equivalents-targeted, mPET). The avoided energy consumptions...... global warming, acidification and nutrification. The studies focus on energy consumption including the emissions and impact categories related to energy. The chemical-related impact categories comprising ecotoxicity and human toxicity are not included at all or only to a limited degree. In this paper we...

  12. Antiphospholipid syndrome: A case study

    International Nuclear Information System (INIS)

    Davies, T.

    1998-01-01

    Full text: A forty-two-year-old male presented to the Royal Adelaide Hospital with symptoms of increasing shortness of breath, swelling in both ankles, petechial rash and blood in his sputum. Initial investigations showed cardiomegaly, right ventricular hypertrophy, patchy lung infiltrates, a platelet count of 1500 and a clotting time of 60 seconds. A V/Q scan indicated a high probability of pulmonary embolism. Further investigations showed that the patient was positive for lupus anticoagulant and cardiolipin antibodies. A diagnosis of primary antiphospholipid syndrome was made. The patient''s high risk of strokes and hemorrhaging prompted investigation by a 99 mTc-HMPAO brain scan. Further V/Q scans were performed to follow up the initial finding of multiple pulmonary embolism and a R-L shunt study was performed to investigate a left subclavian murmur. The patient was admitted for four weeks and began treatment which included cyclaphosphamide, corticosteroids and plasmaphoresis and was discharged when stable. Over the next six months he was re admitted three times for relapse of antiphospholipid syndrome. On his fourth admission he collapsed and died five hours after admission. Cause of death was due to cardiac arrhythmia secondary to severe right ventricular hypertrophy and dilation. The effects of antiphospholipid syndrome was believed to be responsible for this outcome

  13. Antiphospholipid syndrome: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Davies, T. [Royal Adelaide Hospital, Adelaide, SA (Australia). Department of Nuclear Medicine

    1998-03-01

    Full text: A forty-two-year-old male presented to the Royal Adelaide Hospital with symptoms of increasing shortness of breath, swelling in both ankles, petechial rash and blood in his sputum. Initial investigations showed cardiomegaly, right ventricular hypertrophy, patchy lung infiltrates, a platelet count of 1500 and a clotting time of 60 seconds. A V/Q scan indicated a high probability of pulmonary embolism. Further investigations showed that the patient was positive for lupus anticoagulant and cardiolipin antibodies. A diagnosis of primary antiphospholipid syndrome was made. The patient``s high risk of strokes and hemorrhaging prompted investigation by a {sup 99}mTc-HMPAO brain scan. Further V/Q scans were performed to follow up the initial finding of multiple pulmonary embolism and a R-L shunt study was performed to investigate a left subclavian murmur. The patient was admitted for four weeks and began treatment which included cyclaphosphamide, corticosteroids and plasmaphoresis and was discharged when stable. Over the next six months he was re admitted three times for relapse of antiphospholipid syndrome. On his fourth admission he collapsed and died five hours after admission. Cause of death was due to cardiac arrhythmia secondary to severe right ventricular hypertrophy and dilation. The effects of antiphospholipid syndrome was believed to be responsible for this outcome.

  14. Polycyclic Aromatic Hydrocarbons in Fine Particulate Matter ...

    Science.gov (United States)

    This study measured polycyclic aromatic hydrocarbon (PAH) composition in particulate matter emissions from residential cookstoves. A variety of fuel and cookstove combinations were examined, including: (i) liquid petroleum gas (LPG), (ii) kerosene in a wick stove, (iii) wood (10% and 30% moisture content on a wet basis) in a forced-draft fan stove, and (iv) wood in a natural-draft rocket cookstove. LPG combustion had the highest thermal efficiency (~57%) and the lowest PAH emissions per unit fuel energy, resulting in the lowest PAH emissions per useful energy delivered (MJd). The average benzo[a]pyrene (B[a]P) emission factor for LPG was 0.842 µg/MJd; the emission rate was 0.043 µg/min. The highest PAH emissions were from wood burning in the natural-draft stove (209-700 µg B[a]P/MJd). PAH emissions from kerosene were significantly lower than those from the wood burning in the natural-draft cookstove, but higher than those from LPG. It is expected that in rural regions where LPG and kerosene are unavailable or unaffordable, the forced-draft fan stove may be an alternative because its emission factor (5.17-8.07 µg B[a]P/MJd) and emission rate (0.52-0.57 µg/min) are similar to kerosene (5.36 µg B[a]P/MJd and 0.45 µg/min). Compared with wood combustion emissions, LPG stoves emit less total PAH emissions and less fractions of high molecular weight PAHs. Relatively large variations in PAH emissions from LPG call for additional future tests to identify the major

  15. Music in context : Four case studies

    NARCIS (Netherlands)

    Randwijck, R.J.C. van

    2008-01-01

    In his thesis entitled “Music in Context. Four Case Studies”, R.J.C. van Randwijck investigates the context in which music has been created. It is a search in Four Case Studies, approaching four pieces of music from the context in which they were written in order to understand their meaning. The

  16. Case Study: A Separation of Powers Lesson.

    Science.gov (United States)

    Jenkins, Steve

    1986-01-01

    Presents a case study involving students in the issue of separation of powers as applied to the 1952 Immigration and Nationality Act. Students examine the case of Jagdish Rai Chadha, an immigrant threatened with deportation whose problems resulted in 1983 U.S. Supreme Court decision declaring legislative veto provision of Immigration and…

  17. Implementing Product Platforms: A Case Study

    DEFF Research Database (Denmark)

    Nielsen, Ole Fiil; Mortensen, Niels Henrik

    2006-01-01

    The paper describes a case study dealing with the process of creating and implementing a product platform. The paper espessially deals with the fact that to obtain the benefits of platforms a permanent change in behaviour in product development must be ensured. This change in behaviour requires...... acceptance and approval from the organisation in general and the commitment from management to enforce agreed-upon decisions. The case study itself was performed in the Danish company LEGO Group. The case study had two objectives: To create a technical architecture and align this architecture...

  18. Characterization of polycyclic aromatic hydrocarbons (PAH's) present in sampled cooked food

    International Nuclear Information System (INIS)

    Palm Naa-Dedei, L.M.

    2010-07-01

    The study was conducted to determine the levels of Polycyclic Aromatic Hydrocarbons in the following traditionally prepared food: smoked and grilled Scomba japonicus, grilled meat (khebab) and bread sampled from some Ghanaian markets. By way of preparation of traditional food, some food comes into direct contact with smoke or extremely high temperature which are potential sources of Polycyclic Aromatic Hydrocarbon generation. Levels of 20 individual Polycyclic Aromatic Hydrocarbons including acenaphthene, acenaphtyelene, anthanthrene, anthracene, benz(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(e)pyrene, benzo(ghi)perylene, benzo(j)fluoranthene, benzo(k)fluoranthene, chrysene, cyclopenta(cd)pyrene, dibenzo(ah)anthracene, fluoranthene, fluorene, indeno(1,2,3-cd)pyrene, naphthalene, phenanthrene and pyrene were determined in 11 smoked and 5 grilled fish, 4 grilled pieces of meat and 3 loaves of baked bread using gas chromatographic techniques with flame ionization detector. Benzo(a)pyrene, which is one of the few PAH for which a legal limit exists in different types of food matrices and other high molecular weight PAHs suspected to be carcinogenic have been detected in high concentrations in most samples. Bread samples gave mean polycyclic aromatic hydrocarbon concentrations of up to 20.39 μg/kg while khebab samples gave mean polycyclicaromatic hydrocarbon concentrations of up to 67.61 μg/kg. There was positive correlation of 0.987 between levels of polycyclic aromatic hydrocarbon concentrations in khebab samples from locations Osu and Atomic down. There was a positive correlation in the concentrations of the high molecular weight PAHs in all smoked fishes from four locations with values between 0.954 and 0.999 for the correlation between any two groups. The polycyclic aromatic hydrocarbon concentration determined in smoked fish samples deceased in terms of location according to the order Winneba > Madina > Chorkor > Ada.

  19. Case Study: Mini-Case Studies: Small Infusions of Active Learning for Large-Lecture Courses

    Science.gov (United States)

    Carloye, Lisa

    2017-01-01

    In this article, the author introduces the usage of case studies to be an excellent method for engaging students through stories. The author notes she developed a series of mini-case studies that can be implemented, with a little advance preparation, within a 10- to 15-minute window during lecture. What makes them "mini" case studies?…

  20. Case-control studies in neurosurgery.

    Science.gov (United States)

    Nesvick, Cody L; Thompson, Clinton J; Boop, Frederick A; Klimo, Paul

    2014-08-01

    Observational studies, such as cohort and case-control studies, are valuable instruments in evidence-based medicine. Case-control studies, in particular, are becoming increasingly popular in the neurosurgical literature due to their low cost and relative ease of execution; however, no one has yet systematically assessed these types of studies for quality in methodology and reporting. The authors performed a literature search using PubMed/MEDLINE to identify all studies that explicitly identified themselves as "case-control" and were published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Each paper was evaluated for 22 descriptive variables and then categorized as having either met or missed the basic definition of a case-control study. All studies that evaluated risk factors for a well-defined outcome were considered true case-control studies. The authors sought to identify key features or phrases that were or were not predictive of a true case-control study. Those papers that satisfied the definition were further evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. The search detected 67 papers that met the inclusion criteria, of which 32 (48%) represented true case-control studies. The frequency of true case-control studies has not changed with time. Use of odds ratios (ORs) and logistic regression (LR) analysis were strong positive predictors of true case-control studies (for odds ratios, OR 15.33 and 95% CI 4.52-51.97; for logistic regression analysis, OR 8.77 and 95% CI 2.69-28.56). Conversely, negative predictors included focus on a procedure/intervention (OR 0.35, 95% CI 0.13-0.998) and use of the word "outcome" in the Results section (OR 0.23, 95% CI 0.082-0.65). After exclusion of nested case-control studies, the negative correlation between focus on a procedure

  1. Fluorescence, Absorption, and Excitation Spectra of Polycyclic Aromatic Hydrocarbons as a Tool for Quantitative Analysis

    Science.gov (United States)

    Rivera-Figueroa, A. M.; Ramazan, K. A.; Finlayson-Pitts, B. J.

    2004-01-01

    A quantitative and qualitative study of the interplay between absorption, fluorescence, and excitation spectra of pollutants called polycyclic aromatic hydrocarbons (PAHs) is conducted. The study of five PAH displays the correlation of the above-mentioned properties along with the associated molecular changes.

  2. War And Reconstruction: Four Comparative Case Studies

    African Journals Online (AJOL)

    The four case studies are taken from four different continents, four different wars under .... and revolutionary changes in the structures and power relations in society and ..... general public accept nowadays that although states' rights were the ...

  3. BTS Case Study: The Galloway Family Home

    International Nuclear Information System (INIS)

    Brandegee Group

    1999-01-01

    Case study of an energy-efficient Habitat for Humanity house that uses 30% less energy than conventional residential construction. The project was part of the Jimmy Carter Work Project in rural Appalachia in 1997

  4. Abstracts of Remediation Case Studies, Volume 9

    Science.gov (United States)

    This report, published by the Federal Remediation Technologies Roundtable (FRTR), is a collection of recently published abstracts summarizing 13 cost and performance case studies on the use of remediation technologies at contaminated sites.

  5. Review of ORD Nanomaterial Case Studies Workshop

    Science.gov (United States)

    The following is a letter report from the Executive Committee of the BOSC concerning the review of the ORD Nanomaterial Case Studies Workshop: Developing a Comprehensive Environmental Assessment Research Strategy for Nanoscale Titanium Dioxide.

  6. Case Study: Pancreas cancer with Whipple's operation

    African Journals Online (AJOL)

    Keywords: pancreas cancer, Whipple procedure, SASPEN case study ..... Grade A. Grade B. Grade C. Nasogastric tube required. 4-7 days or reinserted > postoperative day 3 .... malabsorption and vitamin and mineral deficiencies are the most.

  7. Innovative Interpretive Qualitative Case Study Research Method ...

    African Journals Online (AJOL)

    lc2o

    The combined use of case study and systems theory is rarely discussed in the ... Scott, 2002), the main benefit of doing qualitative research is the patience ..... Teaching ICT to teacher candidates ... English Language Teachers. London: Arnold.

  8. Memory and Learning: A Case Study.

    Science.gov (United States)

    Webster, Raymond E.

    1986-01-01

    The usefulness of the Learning Efficency Test (LET), an approach to assessing the learning efficiency and short-term memory recall capacity in children, is described via a case study demonstrating the test's use to develop instructional strategies. (CL)

  9. Towards More Case Study Research in Entrepreneurship

    Directory of Open Access Journals (Sweden)

    Tom Duxbury

    2012-03-01

    Full Text Available Entrepreneurship as an emerging discipline has made good strides, but according to some, has fallen short of bringing its theory and literature up to the standards of others in the management sciences. Rich with the descriptive detail needed for insightful theory building in entrepreneurship, scholars have called for more case study research, particularly those incorporating non-retrospective and longitudinal observations. At the same time however, it has become rare to find such research published in A-level journals dedicated to entrepreneurship. A survey presented here of major entrepreneurship journals over the past six years revealed a publication rate of only 3% using the case study method. This presents a major impediment for developing fresh research in this field based upon the study of real cases. The author explores how the case study method has been applied to entrepreneurship research and provides recommendations for improved publication rates.

  10. Travel Efficiency Assessment Method: Three Case Studies

    Science.gov (United States)

    This slide presentation summarizes three case studies EPA conducted in partnership with Boston, Kansas City, and Tucson, to assess the potential benefits of employing travel efficiency strategies in these areas.

  11. Modalities of Generalization Through Single Case Studies.

    Science.gov (United States)

    Zittoun, Tania

    2017-06-01

    The value of case studies for theory building is still doubted in psychology. The paper argues for the importance of case studies and the possibility of generalizing from these for a specific sociocultural understanding of human development. The paper first clarifies the notion of abduction within case studies, drawing on pragmatists James and Peirce and expanding it with the work of Lewin, and argues that it is the core mechanism that allows generalization from case studies. The second section presents the possibility of generalizing from individual single case studies, for which not only the subjective perspective, but also the dynamics by which the social and cultural environment guide and enable the person's development, have to be accounted for. The third section elaborates the question of institutional case studies, where the challenge is to account both for institutional dynamics, and for persons' trajectories within; this is exemplified with an ongoing study on the process of obtaining citizenship in Switzerland. The paper briefly concludes by highlighting two possible implications of the paper, one concerning the process of theoretical reasoning, the other, the fact that sociocultural psychology could itself be seen as an institution in-the-making.

  12. Educational Potential of Case-Study Technology

    OpenAIRE

    Fedorinova, Zoya; Vorobeva, Victoria; Malyanova, Marina

    2015-01-01

    This article presents the results of phenomenological and typological analysis of case-study technology educational potential. The definition “educational potential of case-study technology” is given, the main characteristics of which are changed in communication and collaborative activity quality, appearance of educational initiatives, change of participants’ position in learning process, formation of “collective subject” in collaborative activity, increase of learning (subject) results. Dep...

  13. Performable Case Studies in Ethics Education.

    Science.gov (United States)

    Robeson, Richard; King, Nancy M P

    2017-09-12

    Bioethics education often includes the study of short stories, novels, plays, and films, because such materials present case examples that can highlight relevant issues and questions especially vividly for a wide range of students. In addition, creative writing is widely used in the education of health professional students and in continuing education settings for health professionals. There are very few academic or professional disciplines that do not use case studies, but the case study in dialogic form has not been standard practice for thousands of years. Dramatic arts casuistry-the creation and performance of short case studies designed specifically to raise bioethics issues for discussion-represents an application of literature and the medical humanities that is both unique and uniquely valuable. This essay describes the development and history of a course that has been successfully taught to medical students and graduate bioethics students, in which the class researches, writes, and performs a case study designed to elicit reflection and discussion about a topic and set of bioethics issues of current interest to both academic and general audiences. The model is also suited to the presentation and discussion of existing case studies, both live and via on-demand audio.

  14. Study on Concentration of Particulate Matter with Diameter Less than 10 Microns, Heavy Metals and Polycyclic Aromatic Hydrocarbons Related to PM2.5 in the Ambient Air of Sina Hospital District

    Directory of Open Access Journals (Sweden)

    Majid Kermani

    2014-03-01

    Full Text Available Background:In recent decades, extensive studies have shown a number of short and long-term health effects of particle matters. In addition to particle matters, polycyclic aromatic hydrocarbons (PAHs and heavy metals in airborne particles due to their mutagenic and carcinogenic properties are considered major air pollutants. So, the aim of this study was to evaluate the concentration of PM2.5particulate, 7heavy metal concentrations and 13 PAHs compound associated with fine particles (PM2.5-boud PAHs in the district of Sina hospital, Tehran. Methods: This cross-sectional study was carried out in air of Sina Hospital district in Tehran. Concentrations of fine particulate matter (PM2.5 were determined by gravimetric. Also heavy metal concentrations in samples after digestion were determined with ICP-AES instrument through injection. Then the PAHs compounds from each sample were extracted by ultrasonic method. After this step, extracted sample was injected for analysis by GC-MS and concentration of each compound was read. Results: The daily average concentration of PM2.5 during the study was 41.19 µg/m3.Concentration values for zinc, lead, cadmium, chromium, nickel and arsenic, were 92/69, 05/38, 2/18, 24/4, 19/4 and 34/1 ng/m3 respectively but mercury not found in this study. Average concentrations of PAHs compounds have been variable from0.07 ng/m3 for Chrysene to 1.21ng/m3 for Dibenzo(ahanthracene. Conclusion: In this study, the daily average of PM2.5 concentrations was above the Iranian National PM, WHO (25 µg/m3 and EPA (35 µg/m3 standards established for PM2.5 particles. Heavy metal concentrations in this study were lower than values reported in previous studies in Tehran. The highest concentrations among PAHs compounds belonging toIndeo(cd 1,2,3pyren, Dibenzo(ah anthracene, Benzo (B flouranthin and Benzo (Kflouranthin that all of these compounds are related to vehicle emissions.

  15. Carcinogenic action of polycyclic hydrocarbons in animals and man

    Energy Technology Data Exchange (ETDEWEB)

    Shabad, L M

    1976-01-01

    Polycyclic hydrocarbons are universally present in the atmosphere, soil, lakes and streams, vegetation, and human and animal tissues, the concentrations varying with distance from the sources (heating systems, industrial plants, automobile highways and airports, petroleum refineries, etc.). The most potent of the carcinogens is benz(a)pyrene whose presence in an object, as shown by studies done in the author's laboratory, is an indication that other polycyclic hydrocarbons are also present. These studies also demonstrated that while benz(a)pyrene may accumulate in soil with seasonal fluctuations, it can also be destroyed by certain microorganisms. Other experiments showed that benz(a)pyrene and other such compounds can be destroyed in tissue culture as well as in vivo (e.g., benz(a)pyrene given to cows with fodder was found in their milk but not in meat after they were slaughtered). It is suggested that maximum permissible concentrations be set for benz(a)pyrene in air and water to minimize its potential carcinogenic effects.

  16. A Case Study about Communication Strategies

    Science.gov (United States)

    Lin, Grace Hui Chin

    2011-01-01

    The primary purpose of this case study was to identify what were Taiwanese University English as a Foreign Language (EFL) learners' perceptions about learning communication strategies. This study collected qualitative data about students' beliefs and attitudes as they learned communication strategies. The research question guiding the study was:…

  17. Predicting Students Drop Out: A Case Study

    Science.gov (United States)

    Dekker, Gerben W.; Pechenizkiy, Mykola; Vleeshouwers, Jan M.

    2009-01-01

    The monitoring and support of university freshmen is considered very important at many educational institutions. In this paper we describe the results of the educational data mining case study aimed at predicting the Electrical Engineering (EE) students drop out after the first semester of their studies or even before they enter the study program…

  18. Coal-tar-based pavement sealcoat, polycyclic aromatic Hydrocarbons (PAHs), and environmental health

    Science.gov (United States)

    Mahler, B.J.; Van Metre, P.C.

    2011-01-01

    Studies by the U.S. Geological Survey (USGS) have identified coal-tar-based sealcoat-the black, viscous liquid sprayed or painted on asphalt pavement such as parking lots-as a major source of polycyclic aromatic hydrocarbon (PAH) contamination in urban areas for large parts of the Nation. Several PAHs are suspected human carcinogens and are toxic to aquatic life.

  19. Removal of two polycyclic musks in sewage treatment plants: Freely dissolved and total concentrations

    NARCIS (Netherlands)

    Artola-Garicano, E.; Borkent, I.; Hermens, J.L.M.; Vaes, W.H.J.

    2003-01-01

    In the current study, the removal of slowly degradable hydrophobic chemicals in sewage treatment plants (STPs) has been evaluated with emphasis on the combination of free and total concentration data. Free and total concentrations of two polycyclic musks were determined in each compartment of four

  20. Trapping of polycyclic aromatic hydrocarbons by amphiphilic cyclodextrin functionalized polypropylene nonwovens

    DEFF Research Database (Denmark)

    Lumholdt, Ludmilla; Nielsen, Ronnie Bo Højstrup; Larsen, Kim Lambertsen

    of the textile fibers. In this study we present the ability of amphiphilic CD coated polypropylene nonwovens to trap 8 different polycyclic aromatic hydrocarbons/endocrine disruptors from aqueous solutions thus demonstrating the potential of using the amphiphilic cyclodextrins for water purification....

  1. A 25-year record of polycyclic aromatic hydrocarbons in soils amended with sewage sludges

    DEFF Research Database (Denmark)

    Lichtfouse, Eric; Sappin-Didier, Valérie; Denaix, Laurence

    2005-01-01

    We studied polycyclic aromatic hydrocarbons (PAHs) in crop soils amended with 1000 tonnes dry weight of sewage sludges per 10,000 m(2) from 1974 to 1992, then after sludges addition from 1993 to 1999. The absence of variations of total PAHs levels of control soils, averaging at 123 mu g/Kg, shows...

  2. Extraction of sediment-associated polycyclic aromatic hydrocarbons with granular activated carbon

    NARCIS (Netherlands)

    Rakowska, M.I.; Kupryianchyk, D.; Grotenhuis, J.T.C.; Rijnaarts, H.H.M.; Koelmans, A.A.

    2013-01-01

    Addition of activated carbon (AC) to sediments has been proposed as a method to reduce ecotoxicological risks of sediment-bound contaminants. The present study explores the effectiveness of granular AC (GAC) in extracting polycyclic aromatic hydrocarbon (PAH) from highly contaminated sediments. Four

  3. POLYCYCLIC AROMATIC HYDROCARBON FORMATION IN OPPOSED FLOW DIFFUSION FLAMES OF ETHANE. (R825412)

    Science.gov (United States)

    AbstractThe effect of fuel-side carbon density on the levels of polycyclic aromatic hydrocarbon (PAH) formation in atmospheric pressure, opposed flow, ethane diffusion flames has been studied using heated micro-probe sampling and gas chromatography/mass spectrometry (...

  4. Chronic toxicity of polycyclic aromatic compounds to the springtail Folsomia candida and the enchytraeid Enchytraeus crypticus.

    NARCIS (Netherlands)

    Droge, S.T.J.; Leon Paumen, M; Bleeker, E.A.J.; Kraak, M.H.S.; van Gestel, C.A.M.

    2006-01-01

    An urgent need exists for incorporating heterocyclic compounds and (bio)transformation products in ecotoxicological test schemes and risk assessment of polycyclic aromatic compounds (PACs). The aim of the present study therefore was to determine the chronic effects of (heterocyclic) PACs on two

  5. Life cycle responses of the midge Chironomus riparius to polycyclic aromatic compound exposure

    NARCIS (Netherlands)

    León Paumen, M.; Borgman, E.; Kraak, M.H.S.; van Gestel, C.A.M.; Admiraal, W.

    2008-01-01

    During acute exposure, polycyclic aromatic compounds (PACs) act mainly by narcosis, but during chronic exposure the same compounds may exert sublethal life cycle effects. The aim of this study was therefore to evaluate the chronic effects of sediment spiked PACs on the emergence of the midge

  6. Determination of polycyclic aromatic hydrocarbons in biochar and biochar amended soil

    Science.gov (United States)

    A method for the determination of the 16 USEPA polycyclic aromatic hydrocarbons (PAHs) in biochar and soil amended with biochar was developed. Samples were Soxhlet extracted with acetone:cyclohexane 1:1, and PAHs were analysed by GC-MS after silica gel clean-up. In a comparative study based on reflu...

  7. Polycyclic aromatic hydrocarbons in disks around young solar-type stars

    NARCIS (Netherlands)

    Geers, Vincent Carlo

    2007-01-01

    In this thesis we study the dust around solar-type young stars. In particular, we focus on one specific species of dust, namely the Polycyclic Aromatic Hydrocarbons (PAHs), a family of large molecules, or small grains, that are widely observed in nearby star-forming regions. We address the following

  8. High-resolution gas chromatographic analysis of polycyclic aromatic hydrocarbons and aliphatic hydrocarbons

    International Nuclear Information System (INIS)

    Perez, M.; Gonzalez, D.

    1988-01-01

    A study of the analysis by gas chromatography of aromatic polycyclic hydrocarbons and aliphatic hydrocarbons is presented. The separation has been carried out by glass and fused silica capillary column in two different polar stationary phases OV-1 and SE-54. The limitation and the advantages of the procedure are discussed in terms of separation, sensitivity and precision. (Author) 20 refs

  9. Atmospheric chlorinated polycyclic aromatic hydrocarbons in East Asia.

    Science.gov (United States)

    Kakimoto, Kensaku; Nagayoshi, Haruna; Konishi, Yoshimasa; Kajimura, Keiji; Ohura, Takeshi; Hayakawa, Kazuichi; Toriba, Akira

    2014-09-01

    This study estimates atmospheric concentrations of chlorinated polycyclic aromatic hydrocarbons (ClPAHs) and polycyclic aromatic hydrocarbons (PAHs) in East Asia using a Gas Chromatograph with High Resolution Mass Spectrometer (GC-HRMS). ClPAHs are ubiquitously generated from PAHs through substitution, and some ClPAHs show higher aryl hydrocarbon receptor (AhR)-mediated activities than their parent PAHs. Atmospheric particles were collected using a high-volume air sampler equipped with a quartz-fiber filter. We determined the ClPAH concentrations of atmospheric particles collected in Japan (Sapporo, Sagamihara, Kanazawa, and Kitakyushu), Korea (Busan), and China (Beijing). The concentrations of ClPAHs were highest in the winter Beijing sample, where the total mean concentration was approximately 15-70 times higher than in the winter samples from Japan and Korea. The concentrations of Σ19ClPAHs and Σ9PAHs were significantly correlated in the Kanazawa and the Busan samples. This indicates that within those cities ClPAHs and PAHs share the same origin, implying direct chlorination of parent PAHs. Toxic equivalent concentrations (TEQs) of the total ClPAHs and PAHs were lowest in Kanazawa in the summer, reaching 1.18 and 2610fg-TEQm(-3) respectively, and highest in Beijing in the winter, reaching 627 and 4240000fg-TEQm(-3) respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Case Study Research Methodology in Nursing Research.

    Science.gov (United States)

    Cope, Diane G

    2015-11-01

    Through data collection methods using a holistic approach that focuses on variables in a natural setting, qualitative research methods seek to understand participants' perceptions and interpretations. Common qualitative research methods include ethnography, phenomenology, grounded theory, and historic research. Another type of methodology that has a similar qualitative approach is case study research, which seeks to understand a phenomenon or case from multiple perspectives within a given real-world context.

  11. Case Study Report about Gender Impact Assessment

    DEFF Research Database (Denmark)

    Faber, Stine Thidemann; Agustin, Lise Rolandsen

    2013-01-01

    The aim of this national case study report is to take a closer look at the use of Gender Impact Assessments in Denmark in order to describe the Danish implementation of this specific Gender Mainstreaming method. By way of analyzing two selected cases (two law proposals put forward by The Danish...... Ministry of Employment and the Danish Ministry of Transport, respectively) the aim is to assess the transformative potential of GIA as it is performed in Denmark....

  12. Gigantic Suprapubic Lymphedema: A Case Study

    Directory of Open Access Journals (Sweden)

    Roozbeh Tanhaeivash

    2016-08-01

    Full Text Available We present the first case study of idiopathic gigantic suprapubic lymphedema and buried penis treated with puboscrotal reconstruction in a patient with initial extreme obesity after an extensive weight reduction (120 kg. Massive localized lymphedema of the suprapubic region should be differentiated from the scrotal type. Severe lymphedema could not resolve on its own and weight reduction does not seem to be helpful in such cases.

  13. Levels of Polycyclic Aromatic Hydrocarbons in Maternal Serum and Risk of Neural Tube Defects in Offspring

    Science.gov (United States)

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants, and have been reported to be a risk factor for human neural tube defects (NTDs). We investigated the relationship between PAH concentrations in maternal serum and NTD risk in offspring using a case-control study design, and explored the link between PAH concentrations to household energy usage characteristics and life styles. One hundred and seventeen women who had NTD-affected pregnancies (cases) and 121 women who delivered healthy infants (controls) were recruited in Northern China. Maternal blood samples were collected at pregnancy termination or at delivery. Twenty-seven PAHs were measured by gas chromatography–mass spectrometry. The concentrations of 13 individual PAHs detected were significantly higher in the cases than in the controls. Clear dose–response relationships between concentrations of most individual PAHs and the risk of total NTDs or subtypes were observed, even when potential covariates were adjusted for. High-molecular-weight PAHs (H-PAHs) showed higher risk than low-molecular-weight PAHs (L-PAHs). No associations between PAH concentrations and indoor life styles and energy usage characteristics were observed. It was concluded that maternal exposure to PAHs was associated with an increased risk of NTDs, and H-PAHs overall posed a higher risk for NTDs than L-PAHs. PMID:25488567

  14. Case Study Research: Foundations and Methodological Orientations

    Directory of Open Access Journals (Sweden)

    Helena Harrison

    2017-01-01

    Full Text Available Over the last forty years, case study research has undergone substantial methodological development. This evolution has resulted in a pragmatic, flexible research approach, capable of providing comprehensive in-depth understanding of a diverse range of issues across a number of disciplines. Change and progress have stemmed from parallel influences of historical transformations in approaches to research and individual researcher's preferences, perspectives, and interpretations of this design. Researchers who have contributed to the development of case study research come from diverse disciplines with different philosophical perspectives, resulting in a variety of definitions and approaches. For the researcher new to using case study, such variety can create a confusing platform for its application. In this article, we explore the evolution of case study research, discuss methodological variations, and summarize key elements with the aim of providing guidance on the available options for researchers wanting to use case study in their work. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1701195

  15. POLYCYCLIC AROMATIC HYDROCARBON FAR-INFRARED SPECTROSCOPY

    International Nuclear Information System (INIS)

    Boersma, C.; Mattioda, A. L.; Tielens, A. G. G. M.; Allamandola, L. J.; Bauschlicher, C. W. Jr; Ricca, A.; Peeters, E.

    2011-01-01

    The far-IR characteristics of astrophysically relevant polycyclic aromatic hydrocarbons (PAHs) averaging in size around 100 carbon atoms have been studied using the theoretical spectra in the NASA Ames PAH IR Spectroscopic Database. These spectra were calculated using density functional theory. Selections of PAH species are made, grouped together by common characteristics or trends, such as size, shape, charge, and composition, and their far-IR spectra compared. The out-of-plane modes involving the entire molecule are explored in detail, astronomical relevance is assessed, and an observing strategy is discussed. It is shown that PAHs produce richer far-IR spectra with increasing size. PAHs also produce richer far-IR spectra with increasing number of irregularities. However, series of irregular-shaped PAHs with the same compact core have common 'Jumping-Jack' modes that 'pile up' at specific frequencies in their average spectrum. For the PAHs studied here, around 100 carbon atoms in size, this band falls near 50 μm. PAH charge and nitrogen inclusion affect band intensities but have little effect on far-IR band positions. Detailed analysis of the two-dimensional, out-of-plane bending 'drumhead' modes in the coronene and pyrene 'families' and the one-dimensional, out-of-plane bending 'bar' modes in the acene 'family' show that these molecular vibrations can be treated as classical vibrating sheets and bars of graphene, respectively. The analysis also shows that the peak position of these modes is very sensitive to the area of the emitting PAH and does not depend on the particular geometry. Thus, these longest wavelength PAH bands could provide a unique handle on the size of the largest species in the interstellar PAH family. However, these bands are weak. Observing highly excited regions showing the mid-IR bands in which the emission from classical dust peaks at short wavelengths offers the best chance of detecting PAH emission in the far-IR. For these regions

  16. Polycyclic Aromatic Hydrocarbon Far-infrared Spectroscopy

    Science.gov (United States)

    Boersma, C.; Bauschlicher, C. W., Jr.; Ricca, A.; Mattioda, A. L.; Peeters, E.; Tielens, A. G. G. M.; Allamandola, L. J.

    2011-03-01

    The far-IR characteristics of astrophysically relevant polycyclic aromatic hydrocarbons (PAHs) averaging in size around 100 carbon atoms have been studied using the theoretical spectra in the NASA Ames PAH IR Spectroscopic Database. These spectra were calculated using density functional theory. Selections of PAH species are made, grouped together by common characteristics or trends, such as size, shape, charge, and composition, and their far-IR spectra compared. The out-of-plane modes involving the entire molecule are explored in detail, astronomical relevance is assessed, and an observing strategy is discussed. It is shown that PAHs produce richer far-IR spectra with increasing size. PAHs also produce richer far-IR spectra with increasing number of irregularities. However, series of irregular-shaped PAHs with the same compact core have common "Jumping-Jack" modes that "pile up" at specific frequencies in their average spectrum. For the PAHs studied here, around 100 carbon atoms in size, this band falls near 50 μm. PAH charge and nitrogen inclusion affect band intensities but have little effect on far-IR band positions. Detailed analysis of the two-dimensional, out-of-plane bending "drumhead" modes in the coronene and pyrene "families" and the one-dimensional, out-of-plane bending "bar" modes in the acene "family" show that these molecular vibrations can be treated as classical vibrating sheets and bars of graphene, respectively. The analysis also shows that the peak position of these modes is very sensitive to the area of the emitting PAH and does not depend on the particular geometry. Thus, these longest wavelength PAH bands could provide a unique handle on the size of the largest species in the interstellar PAH family. However, these bands are weak. Observing highly excited regions showing the mid-IR bands in which the emission from classical dust peaks at short wavelengths offers the best chance of detecting PAH emission in the far-IR. For these regions

  17. Polycyclic Aromatic Hydrocarbons and Esophageal Squamous Cell Carcinoma-A Review

    Science.gov (United States)

    Roshandel, Gholamreza; Semnani, Shahryar; Malekzadeh, Reza; Dawsey, Sanford M.

    2018-01-01

    Esophageal cancer (EC) is the 8th most common cancer and the 6th most frequent cause of cancer mortality worldwide. Esophageal squamous cell carcinoma (ESCC) is the most common type of EC. Exposure to polycyclic aromatic hydrocarbons (PAHs) has been suggested as a risk factor for developing ESCC. In this paper we will review different aspects of the relationship between PAH exposure and ESCC. PAHs are a group of compounds that are formed by incomplete combustion of organic matter. Studies in humans have shown an association between PAH exposure and development of ESCC in many populations. The results of a recent case-control study in a high risk population in northeastern Iran showed a dramatic dose-response relationship between PAH content in non-tumor esophageal tissue (the target tissue for esophageal carcinogenesis) and ESCC case status, consistent with a causal role for PAH exposure in the pathogenesis of ESCC. Identifying the main sources of exposure to PAHs may be the first and most important step in designing appropriate PAH-reduction interventions for controlling ESCC, especially in high risk areas. Coal smoke and drinking mate have been suggested as important modifiable sources of PAH exposure in China and Brazil, respectively. But the primary source of exposure to PAHs in other high risk areas for ESCC, such as northeastern Iran, has not yet been identified. Thus, environmental studies to determining important sources of PAH exposure should be considered as a high priority in future research projects in these areas. PMID:23102250

  18. Collaborative Assessment: Middle School Case Study

    Science.gov (United States)

    Parkison, Paul T.

    2014-01-01

    Utilizing a participant observer research model, a case study of the efficacy of a collaborative assessment methodology within a middle school social studies class was conducted. A review of existing research revealed that students' perceptions of assessment, evaluation, and accountability influence their intrinsic motivation to learn. A…

  19. Case Studies in Library Computer Systems.

    Science.gov (United States)

    Palmer, Richard Phillips

    Twenty descriptive case studies of computer applications in a variety of libraries are presented in this book. Computerized circulation, serial and acquisition systems in public, high school, college, university and business libraries are included. Each of the studies discusses: 1) the environment in which the system operates, 2) the objectives of…

  20. Prader-Willi Disease: A Case Study.

    Science.gov (United States)

    Forbus, William R., III

    A case study focuses on the characteristics and physical management of a 15-year-old with Prader-Willi Syndrome, a birth defect associated with hypotonia, insatiable appetite, hypogonadism, central nervous system dysfunction, and abnormal growth and development . A literature review addresses studies dealing with behavior modification of obesity…

  1. Degradation and utilization of polycyclic aromatic hydrocarbons by indigenous soil bacteria

    International Nuclear Information System (INIS)

    Stetzenbach, L.D.A.

    1986-01-01

    The persistence of industrially derived polycyclic aromatic hydrocarbons in the subsurface may be significantly affected by the metabolism of soil bacteria. This study was conducted to determine the ability of indigenous soil bacteria to decrease the concentration of four polycyclic aromatic hydrocarbons (naphthalene, fluorene, anthracene, and pyrene) and to utilize the compounds as a substrate for growth. Soil cores from petroleum contaminated and noncontaminated sites contained 10 5 -10 7 viable microorganisms per gram dryweight of soil. Gram negative rod-shaped bacteria predominated. Decreases in the concentration of the four polycyclic aromatic hydrocarbons were observed during incubation with bacterial isolates in aqueous suspension by the use of high performance liquid chromatography. Corresponding increases in bacterial numbers indicated utilization of the compounds as a carbon source. Soil samples from the contaminated sites contained greater numbers of bacteria utilizing anthracene and pyrene than soil samples from uncontaminated sites. Degradation rates of the four polycyclic aromatic hydrocarbons were related to the compound, its concentration, and the bacterium. Biodegradation of pyrene was positively correlated with the presence of oxygen. Pyrene was biodegraded by an Acinetobacter sp. under aerobic conditions but not under anaerobic or microaerophilic conditions. Studies with radiolabeled 14 C-anthracene demonstrated utilization of the labeled carbon as a source of carbon by viable bacterial cells in aqueous suspension. Incorporation of 14 C into cellular biomass however was not observed during incubation of 14 C-anthracene in soil

  2. Mining Product Data Models: A Case Study

    Directory of Open Access Journals (Sweden)

    Cristina-Claudia DOLEAN

    2014-01-01

    Full Text Available This paper presents two case studies used to prove the validity of some data-flow mining algorithms. We proposed the data-flow mining algorithms because most part of mining algorithms focuses on the control-flow perspective. First case study uses event logs generated by an ERP system (Navision after we set several trackers on the data elements needed in the process analyzed; while the second case study uses the event logs generated by YAWL system. We offered a general solution of data-flow model extraction from different data sources. In order to apply the data-flow mining algorithms the event logs must comply a certain format (using InputOutput extension. But to respect this format, a set of conversion tools is needed. We depicted the conversion tools used and how we got the data-flow models. Moreover, the data-flow model is compared to the control-flow model.

  3. Cryostat design case studies, principles and engineering

    CERN Document Server

    2016-01-01

    This book enables the reader to learn the fundamental and applied aspects of practical cryostat design by examining previous design choices and resulting cryostat performance. Through a series of extended case studies the book presents an overview of existing cryostat design covering a wide range of cryostat types and applications, including the magnet cryostats that comprise the majority of the Large Hadron Collider at CERN, space-borne cryostats containing sensors operating below 1 K, and large cryogenic liquid storage vessels. It starts with an introductory section on the principles of cryostat design including practical data and equations. This section is followed by a series of case studies on existing cryostats, describing the specific requirements of the cryostat, the challenges involved and the design choices made along with the resulting performance of the cryostat. The cryostat examples used in the studies are chosen to cover a broad range of cryostat applications and the authors of each case are ...

  4. Clean Cities Case Study: Barwood Cab Fleet Study Summary

    International Nuclear Information System (INIS)

    Whalen, P.

    1999-01-01

    Barwood Cab Fleet Study Summary is the second in a new series called''Alternative Fuel Information Case Studies,'' designed to present real-world experiences with alternative fuels to fleet managers and other industry stakeholders

  5. Repurposing legacy data innovative case studies

    CERN Document Server

    Berman, Jules J

    2015-01-01

    Repurposing Legacy Data: Innovative Case Studies takes a look at how data scientists have re-purposed legacy data, whether their own, or legacy data that has been donated to the public domain. Most of the data stored worldwide is legacy data-data created some time in the past, for a particular purpose, and left in obsolete formats. As with keepsakes in an attic, we retain this information thinking it may have value in the future, though we have no current use for it. The case studies in this book, from such diverse fields as cosmology, quantum physics, high-energy physics, microbiology,

  6. Case studies in atomic collision physics

    CERN Document Server

    McDaniel, E W

    1974-01-01

    Case Studies in Atomic Physics III focuses on case studies on atomic and molecular physics, including atomic collisions, transport properties of electrons, ions, molecules, and photons, interaction potentials, spectroscopy, and surface phenomena. The selection first discusses detailed balancing in the time-dependent impact parameter method, as well as time-reversal in the impact parameter method and coupled state approximation. The text also examines the mechanisms of electron production in ion. Topics include measurement of doubly differential cross sections and electron spectra, direct Coul

  7. An Evaluation of Uncertainty Associated to Analytical Measurements of Selected Polycyclic Aromatic Compounds in Ambient Air

    International Nuclear Information System (INIS)

    Barrado, A. I.; Garcia, S.; Perez, R. M.

    2013-01-01

    This paper presents an evaluation of uncertainty associated to analytical measurement of eighteen polycyclic aromatic compounds (PACs) in ambient air by liquid chromatography with fluorescence detection (HPLC/FD). The study was focused on analyses of PM 1 0, PM 2 .5 and gas phase fractions. Main analytical uncertainty was estimated for eleven polycyclic aromatic hydrocarbons (PAHs), four nitro polycyclic aromatic hydrocarbons (nitro-PAHs) and two hydroxy polycyclic aromatic hydrocarbons (OH-PAHs) based on the analytical determination, reference material analysis and extraction step. Main contributions reached 15-30% and came from extraction process of real ambient samples, being those for nitro- PAHs the highest (20-30%). Range and mean concentration of PAC mass concentrations measured in gas phase and PM 1 0/PM 2 .5 particle fractions during a full year are also presented. Concentrations of OH-PAHs were about 2-4 orders of magnitude lower than their parent PAHs and comparable to those sparsely reported in literature. (Author)

  8. Polycyclic Aromatic Hydrocarbon Residues in Serum Samples of Autopsied Individuals from Tennessee

    Directory of Open Access Journals (Sweden)

    Aramandla Ramesh

    2014-12-01

    Full Text Available This study reports the concentrations of Polycyclic Aromatic Hydrocarbons (PAHs in human blood sera samples (n = 650 obtained at autopsy from individuals who died of drug abuse, alcohol toxicity, homicide, suicide and other unknown causes. The analyzed samples from decedents revealed the presence of PAHs of which B(aP was the most predominant one, followed by benzo(bfluoranthene and benzo(kfluoranthene. The other PAHs detected sporadically and measured were benzo(g,h,iperylene, acenaphthene, anthracene, phenanthrene, and fluoranthene The mean concentrations of PAHs were greater in the twenties to fifties age groups compared to others. The PAH residue levels detected were high in African Americans compared to Caucasians, Asians, and Hispanics. It appears that environmental exposure, dietary intake and in some cases occupational exposure may have contributed to the PAH body burden. While the PAH residue concentrations measured fall within the range of those reported for healthy adults elsewhere, in isolated cases, the concentrations detected were high, calling the need for a reduction in PAH emissions and human biomonitoring studies for purposes of risk assessment.

  9. Financial Shenanigans : A Case Study in Malaysia

    OpenAIRE

    Ooi, Ki Wei

    2013-01-01

    This study investigates the financial shenanigan cases which subject to the enforcement actions by the Malaysian Securities Commission between 2006 and 2011 for alleged financial misreporting. The scope of this study includes the attempts used, causes and consequences of the financial shenanigans and the post-financial shenanigans recovery plans devised to turnaround the companies. This study finds that the most common attempt used by the sample companies is overstating the revenue, follows b...

  10. Financial Shenanigans : A Case Study of Nigeria

    OpenAIRE

    Onitilo, Nnenna Chidimma

    2015-01-01

    This study investigates the identified cases of financial shenanigans in between 2001 and 2009 in Nigeria. The scope of this study includes the identification of the common attempts and approaches used by companies and the motivations for financial shenanigans. A cross country comparison of the characteristics of the corporate reporting environments between Nigeria and Malaysia was also carried out. This study finds that the most common attempt used by the sample companies are majorly revenue...

  11. A Review of Polycyclic Aromatic Hydrocarbons and Heavy Metal ...

    African Journals Online (AJOL)

    A Review of Polycyclic Aromatic Hydrocarbons and Heavy Metal Contamination of Fish from Fish Farms. ... Journal of Applied Sciences and Environmental Management ... Polycyclic aromatic hydrocarbons (PAHs) and heavy metals contribute to pollutants in aquaculture facilities and thus need to be further investigated.

  12. The role of radionuclide studies in emergency cases

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Hayashida, Kohei; Uehara, Toshiisa

    1982-01-01

    Radionuclide studies have been performed popularly because of its noninvasive and simple method recently. In this study, we applied this technique for the evaluation of emergency cases in cardiovascular diseases. There were 93 cases (1.5%) out of 6163 cases, done during 1981. The subjects were 34 cases of cardiac studies (9 cases of sup(99m)Tc-PYP myocardial imaging, 12 cases of thallium myocardial imaging, 13 cases of cardioangiography), 23 cases of peripheral diseases (12 cases of peripheral angiography, 11 cases of venography), 16 cases of pulmonary imaging, 10 cases of renal studies (6 cases of renal angiography, 9 cases of renal imaging) and 5 cases of brain angiography. These studies were proven to be useful clinically for the evaluation of emergency cases and follow-up studies. In the near future, ''emergency radionuclide studies'' would be benefit for the high-risk patients noninvasively. (author)

  13. STUDY OF 200 CASES OF PLEURAL FLUID

    Directory of Open Access Journals (Sweden)

    Ramakrishna R

    2016-09-01

    Full Text Available BACKGROUND We have studied 200 patients of pleural fluid presenting to our tertiary care centre. Presence of cases of pleural fluid is a common presentation both in pulmonary and extrapulmonary diseases. We analysed the patients having both exudates and transudates and studied the results. MATERIALS AND METHODS We selected patients above 20 years of age and classified the patients with pleural fluid as having transudates and exudates. We studied the causes of transudates and exudates. A total of 200 patients are studied in this prospective study. Diagnosis of pleural exudates is made on the basis of Light’s criteria, chest x-ray, pleural fluid analysis, CT scan in selected patients, sputum examination, bronchoscopy and bronchial washings. Moribund and non-cooperative patients and HIV positives were excluded from the study. RESULTS Among the 200 patients, 91% have exudates. 9% have transudates by Light’s criteria. Tuberculosis is the commonest cause of effusions (64.83% followed by malignancy (13.73% and sympneumonic or parapneumonic effusions (9.89%. Pleural effusions occurred predominantly in males. Prevalence of diabetes Mellitus among cases of tuberculous pleural effusions is 13.56%. Tuberculous effusions are predominantly right-sided. CONCLUSION Predominant cases of pleural fluid are exudates. Commonest cause of pleural effusion is Tuberculosis followed by malignancy both pulmonary and extrapulmonary and sym. and parapneumonic effusions. Prevalence of Diabetes among Tuberculous pleural effusion cases is more or less same as in general population. Cough, expectoration fever, chest pain and breathlessness are the common symptoms occurring in three fourths of the patients of tuberculous pleural effusion. Most of the cases of Tuberculous effusion are above 30 years of age. In the diagnosis of tuberculous pleural effusion, Pleural fluid ADA is very important. Pleural fluid cytology, pleural biopsy, bronchoscopy, bronchial washings and sputum

  14. A Codesign Case Study in Computer Graphics

    DEFF Research Database (Denmark)

    Brage, Jens P.; Madsen, Jan

    1994-01-01

    The paper describes a codesign case study where a computer graphics application is examined with the intention to speed up its execution. The application is specified as a C program, and is characterized by the lack of a simple compute-intensive kernel. The hardware/software partitioning is based...

  15. Effective communication. A Platonic case study

    NARCIS (Netherlands)

    Wakker, Gerry C.; Wieling, Martijn; Kroon, Martin; Van Noord, Gertjan

    As a contribution to the valedictory volume for John Nerbonne I present a case study of two thematically similar passages in Plato where I will make use of an analysis based on discourse cohesion and above all on the rhetorical and manipulative use of particles to show how a single (leading)

  16. The Danish National Case Study Report

    DEFF Research Database (Denmark)

    Brodersen, Søsser; Jørgensen, Michael Søgaard

    the projects so it fits into the university schedule, without leaving out the time perspective of the clients, and secure the research is applicable for the clients and based on their need for knowledge. The case studies have shown different roles of a Science Shop. All Science Shops have a role as mediator...

  17. Portfolio Manager Selection – A Case Study

    DEFF Research Database (Denmark)

    Christensen, Michael

    2017-01-01

    Within a delegated portfolio management setting, this paper presents a case study of how the manager selection process can be operationalized in practice. Investors have to pursue a thorough screening of potential portfolio managers in order to discover their quality, and this paper discusses how...

  18. Acoustical case studies of three green buildings

    Science.gov (United States)

    Siebein, Gary; Lilkendey, Robert; Skorski, Stephen

    2005-04-01

    Case studies of 3 green buildings with LEED certifications that required extensive acoustical retrofit work to become satisfactory work environments for their intended user groups will be used to define areas where green building design concepts and acoustical design concepts require reconciliation. Case study 1 is an office and conference center for a city environmental education agency. Large open spaces intended to collect daylight through clerestory windows provided large, reverberant volumes with few acoustic finishes that rendered them unsuitable as open office space and a conference room/auditorium. Case Study 2 describes one of the first gold LEED buildings in the southeast whose primary design concepts were so narrowly focused on thermal and lighting issues that they often worked directly against basic acoustical requirements resulting in sound levels of NC 50-55 in classrooms and faculty offices, crosstalk between classrooms and poor room acoustics. Case study 3 is an environmental education and conference center with open public areas, very high ceilings, and all reflective surfaces made from wood and other environmentally friendly materials that result in excessive loudness when the building is used by the numbers of people which it was intended to serve.

  19. Advanced supplier partnership practices: a case study.

    Science.gov (United States)

    Williams, B R

    2000-05-01

    This article describes how a supplier partnership was set up to avoid the typical purchasing relationship--price being inversely proportional to quantity and having the purchaser take all the risk of product obsolescence. The case study also describes how rate-based replenishment replaced time-based delivery, and how all these advantages were achieved at reduced administrative costs.

  20. Management in Virtual Environments. Case Studies

    OpenAIRE

    Mazurek, Grzegorz; Gembicki, Michał; Krzemień, Grzegorz; Przegalińska, Aleksandra K.; Starostka, Justyna; Skorulska, Karolina; Prystupa-Rządca, Kaja

    2015-01-01

    The following publication consists of 12 case studies, which encompass various aspects of the ICT impact on contemporary businesses, focusing – among other things – on such concepts as: crowdsourcing, the internet of things, design thinking, digital entertainment, e-commerce, online and off-line distribution or social media marketing. EEA, Norway Grants Anna Goryńska

  1. Teaching Business Intelligence through Case Studies

    Science.gov (United States)

    Pomykalski, James J.

    2015-01-01

    In teaching business students about the application and implementation of technology, especially involving business intelligence, it is important to discover that project success in enterprise systems development efforts often depend on the non-technological problems or issues. The focus of this paper will be on the use of multiple case studies in…

  2. Business Registration Reform Case Studies : Malaysia

    OpenAIRE

    Olaisen, John

    2009-01-01

    This collection of case studies describes experiences and draws lessons from varied business registration reform programs in economies in vastly different stages of development: Bulgaria, Estonia, Ireland, Madagascar, and Malaysia. Over the last twenty years, a number of countries have recognized the importance of smooth and efficient business start up procedures. A functioning business re...

  3. Predicting students drop out : a case study

    NARCIS (Netherlands)

    Dekker, G.W.; Pechenizkiy, M.; Vleeshouwers, J.M.; Barnes, T.; Desmarais, M.; Romero, C.; Ventura, S.

    2009-01-01

    The monitoring and support of university freshmen is considered very important at many educational institutions. In this paper we describe the results of the educational data mining case study aimed at predicting the Electrical Engineering (EE) students drop out after the first semester of their

  4. WP6 - The Ag2020 Case Studies

    DEFF Research Database (Denmark)

    Hansen, Jens G; Borch, Kristian; Trombi, Giacomo

    2010-01-01

    of the Future are presented. Finally, in section 1.4, is described the structure of the present report,which is firmly followed by the four case studies involved in the Project, namely the Rhodope Mountainous region in Bulgaria (CS1), The Kastelli region (Herakleion nomos) in Greece (CS2), the Central Denmark...

  5. case study of ramat park benin city

    African Journals Online (AJOL)

    user

    SETTLEMENT: CASE STUDY OF RAMAT PARK BENIN CITY. E. S. Okonofua1, R. ... region on a daily basis. The movement of ... with major road networks [2]. In order to ease ... led to series of research and development of traffic noise models.

  6. CASE STUDY – HIV AND LUNG DISEASE

    African Journals Online (AJOL)

    2011-04-02

    Apr 2, 2011 ... pathology deep to the paraseptal bullae. An intercostal drain tip is seen in the left lateral pleural space. Fig. 2. Axial computed tomography scan on lung windows. Large bilateral paraseptal bullae are demonstrated with residual antero-medial pneumothorax. 37. CASE STUDY – HIV AND LUNG DISEASE ...

  7. A Case Study of the Vredefort Dome

    African Journals Online (AJOL)

    South Africa became a signatory to and ratified the World Heritage Convention, 1972 (WHC) in 1997. It thereby voluntarily agreed to identify and conserve world heritage areas of universal value for the benefit of mankind. This article presents a case study of the Vredefort Dome, one of South Africa\\'s World Heritage Sites ...

  8. Climate wise case study compendium: Report 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    This case study compendium is one of several Climate Wise tools available to help interested companies identify cost-effective options. Climate Wise, a private-public partnership program, is a key Federal initiative to return greenhouse gas emissions to 1990 levels by 2000.

  9. Making Professional Development Flexible: A Case Study.

    Science.gov (United States)

    Forsyth, Rachel

    2002-01-01

    Presents a case study of an online course that was designed for staff professional development at Manchester Metropolitan University (United Kingdom). Discusses the flexibility of online courses; course design; activities for short online workshops; evaluation methods for course evaluation; and results of participant questionnaires. (LRW)

  10. Library Virtual Tours: A Case Study

    Science.gov (United States)

    Ashmore, Beth; Grogg, Jill E.

    2004-01-01

    Virtual tours delivered via the Web have become a common tool for both instruction and outreach. This article is a case study of the creation of a virtual tour for a university library and is intended to provide others interested in creating a virtual tour of their library the opportunity to learn from the mistakes and successes of fellow…

  11. Learning Machine Learning: A Case Study

    Science.gov (United States)

    Lavesson, N.

    2010-01-01

    This correspondence reports on a case study conducted in the Master's-level Machine Learning (ML) course at Blekinge Institute of Technology, Sweden. The students participated in a self-assessment test and a diagnostic test of prerequisite subjects, and their results on these tests are correlated with their achievement of the course's learning…

  12. Firefighter Workplace Learning: An Exploratory Case Study

    Science.gov (United States)

    Tracey, Edward A.

    2014-01-01

    Despite there being a significant amount of research investigating workplace learning, research exploring firefighter workplace learning is almost nonexistent. The purpose of this qualitative multi-case study was to explore how firefighters conceptualize, report, and practice workplace learning. The researcher also investigated how firefighters…

  13. Spicy Stonehenge : Proposing a SOA Case Study

    NARCIS (Netherlands)

    Espinha, T.A.; Chen, C.; Zaidman, A.E.; Gross, H.G.

    2012-01-01

    Prepint of paper published in: ICSE Workshop on Principles of Engineering Service Oriented Systems (PESOS), 4 June 2012; doi:10.1109/PESOS.2012.6225940 Maintenance research in the context of Service Oriented Architecture (SOA) is currently lacking a suitable standard case study that can be used by

  14. Collegiality in education: a case study

    African Journals Online (AJOL)

    Erna Kinsey

    This case study therefore investigated the effects of a collegial management style on teaching and learning ... resources cannot solely guarantee success at matriculation level. ... vily on school principals, their management teams and the governing .... may be necessary to employ the notion of building with a new member.

  15. It's Not Funny: A Case Study

    Science.gov (United States)

    Méndez-Morse, Sylvia

    2015-01-01

    This case study may be used with personnel supervision, school law, and other school leadership courses. It describes the behavior and actions of one teacher toward another. Student discussions can focus on supervision, workplace mobbing, workplace bullying, as well as sexual harassment. Students should focus on a school leader's role in such…

  16. Teaching the Holocaust through Case Study

    Science.gov (United States)

    Misco, Thomas

    2009-01-01

    This article responds to the curricular challenges teachers face with Holocaust education, including cursory treatments and a lack of focus on individual experiences. First, the author argues for a case-study approach to help students reengage concrete and complex features of the Holocaust as a point of departure for subsequent inquiry. In…

  17. A case study of Florida Road, Durban

    African Journals Online (AJOL)

    2006-06-29

    Jun 29, 2006 ... planning in mixed-use precincts: A case study of .... Technology, Faculty of Engineering and the Built Environment, Department of Town and Regional .... development process of contemporary cities. The origins of this realisation .... financing, and a lack of collaboration .... surrounded by a transport network,.

  18. Nanomaterial Case Studies: Nanoscale Titanium Dioxide ...

    Science.gov (United States)

    This draft document presents two case studies of nanoscale titanium dioxide (nano-TiO2) used (1) to remove arsenic from drinking water and (2) as an active ingredient in topical sunscreen. The draft case studies are organized around a comprehensive environmental assessment approach that combines a product life cycle framework with the risk assessment paradigm. The document does not draw conclusions about potential risks. Rather, the case studies are intended to help identify what needs to be known in order to conduct a comprehensive environmental assessment of the potential risks related to nano-TiO2. This draft document is part of a process that will inform the development of EPA’s research strategy to support nanomaterial risk assessments. The complex properties of various nanomaterials make evaluating them in the abstract or with generalizations difficult if not impossible. Thus, this document focuses on two specific uses of nano-TiO2, as a drinking water treatment and as topical sunscreen. These case studies do not represent completed or even preliminary assessments; rather, they present the structure for identifying and prioritizing research needed to support future assessments.

  19. Characterisation and comparison of case study findings

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Dorland, Jens; Pel, Bonno

    2015-01-01

    This report gives an overview and a comparative analysis of the findings from the 12 first case study reports in TRANSIT about aspects of transformative social innovation (TSI). Each of the 12 reports, on which the report is based, includes an analysis of a transnational social innovation network...

  20. Hydrocarbon storage caverns overhaul: A case study

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, N. [Bayer Inc., Sarnia, ON (Canada)

    1998-09-01

    Case studies of four hydrocarbon storage cavern overhauls by Bayer Inc., of Sarnia during the period 1993 to 1997 were reviewed and the lessons learned were discussed. Discussions included inspection requirements for each of the caverns, the logistics and planning plant production around the cavern outages, site and cavern preparation, including removal of the casing slips from the well heads. It was emphasized that cavern overhauls can be expensive operations, unless preceded by proper planning. The largest variable cost is likely to be rig time at about $ 2,000 per day. Planning for the unexpected with thoughtful contingencies can reduce costs and avoid expensive delays.

  1. Polycyclic aromatic hydrocarbons in stellar medium

    Science.gov (United States)

    Rastogi, Shantanu

    2005-06-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are an important com- ponent of the Interstellar Medium (ISM). They are being used as probes for understanding of process and conditions of different astrophysical environments. The understanding of their IR spectra and its variations with PAH size and ionization state is useful in characterizing the ISM. Spectral features of model graphene sheets and also that of smaller PAH molecules are reported. The variation of intensity with charge state of the molecule shows that cations give a better correlation with observations. The relationship between changes in charge distribution with intensity changes upon ionization has been probed.

  2. Microbial degradation of polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Volkering, F.; Breure, A.M.; Andel, J.G. van

    1992-01-01

    Polycyclic aromatic hydrocarbons (PAH) are hazardous compounds originating from oil, tar, creosote, or from incomplete combustion of fossil fuels. Application of biotechnological techniques for remediation of polluted soils from PAH demonstrated that the high molecular compounds are degraded very slowly, and that the residual concentration of PAH often is too high to permit application of the treated soil. Investigations were started to establish process parameters for optimal biodegradation of PAH. The aim is to achieve a relation between the physical properties of PAH and the biodegradation kinetics in different matrices, in order to identify applicability of biotechnological cleanup methods for waste streams and polluted soil. (orig.) [de

  3. The Influence of Multiwalled Carbon Nanotubes on Polycyclic Aromatic Hydrocarbon (PAH) Bioavailability and Toxicity to Soil Microbial Communities in Alfalfa Rhizosphere

    Science.gov (United States)

    Carbon nanotubes (CNTs) may affect bioavailability and toxicity of organic contaminants due to their adsorption properties. Recent studies have observed the influence of multiwalled carbon nanotubes (MWNTs) on the fate of polycyclic aromatic hydrocarbons (PAHs) and other organic contaminants. Greenh...

  4. Development and validation of a direct sandwich chemiluminescence immunoassay for measuring DNA adducts of benzo[a]pyrene and other polycyclic aromatic hydrocarbons

    DEFF Research Database (Denmark)

    Georgiadis, Panagiotis; Kovács, Katalin; Kaila, Stella

    2012-01-01

    We have developed and validated a sandwich chemiluminescence immunoassay (SCIA) which measures polycyclic aromatic hydrocarbon (PAH)-DNA adducts combining high throughput and adequate sensitivity, appropriate for evaluation of adduct levels in human population studies. Fragmented DNA is incubated...

  5. Synthesis across social innovation case studies

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Avelino, Flor; Dorland, Jens

    2016-01-01

    Part 1 is an overview and a comparative analysis of the findings from the 20 case study reports in TRANSIT about aspects of transformative social innovation (TSI). Each of the 20 reports, which the report is based on, includes an analysis of a transnational social innovation network and at least...... two local social innovation initiatives. Part 2 consists of extended abstracts of 8 papers which either focus on empirical phenomena surfacing in different TRANSIT cases (e.g. alternative economic arrangements), take a societal or methodological issue as starting point (e.g. inclusivity or research...... relations), address propositions from TRANSIT proto-theory (institutionalization dialectics, responses to crisis), build upon thematic clusters used for case selection (e.g. spaces for/of innovation, inclusive society, new economy, transformative science) or inductively develop specific sensitizing concepts...

  6. Neonatal appendicitis: a survival case study

    Directory of Open Access Journals (Sweden)

    Izabela Linha Secco

    Full Text Available ABSTRACT Objective: To report a case of neonatal appendicitis in a children’s hospital in southern Brazil, demonstrating the impact on neonatal survival. Method: Case study with data collection from medical records, approved by the Institution and Ethics Committee for Research with Human Beings. Results: The clinical picture is initially characterized by food intolerance, evolving to hypoactivity, alteration of vital signs and septicemia due to intestinal perforation. Management is exclusively surgical, since no case described in the literature was diagnosed preoperatively and the findings usually point to acute abdomen. Conclusion: A focused clinical surveillance should be established when the infant presents peritoneal irritation. Follow-up of the evolution and the worsening of the symptoms by nurses, as part of the care team in partnership with the medical team, enables an early surgical intervention, thereby avoiding complications such as septicemia and death.

  7. Case studies on selected natural food antioxidants

    OpenAIRE

    Herrero, Miguel; Mendiola, J. A.; Cifuentes, Alejandro; Ibáñez, Elena

    2013-01-01

    In this chapter, a broad description of several case studies related to common antioxidants found in food-related products is presented. In this regard, special attention is put on the novel advanced environmentally-friendly extraction methods nowadays employed to extract and purify those potent antioxidants from natural matrices. A brief description of these extraction processes is provided together with some of the instrumentation needed. Besides, the studies carried out so f...

  8. On robust analysis of paycheck: case study

    Directory of Open Access Journals (Sweden)

    Michal Uherek

    2011-01-01

    Full Text Available Many statistical tests are constructed to check the validity of normal distribution. Here we propose a case study on analysis of paycheck where we employ the RT class of tests for normality firstly introduced in Střelec, Stehlík (2008. In particular such a study can be of interest for pension funds theoreticians and practitioners, which study the transitions of pension systems from one social security state to the another one. Our study illustrates some possible distributional deviations of salary residuals on a real data.

  9. Polycyclic Aromatic Hydrocarbons in Electrocautery Smoke during Peritonectomy Procedures

    Directory of Open Access Journals (Sweden)

    Sara Näslund Andréasson

    2012-01-01

    Full Text Available Objective. This study identified and quantified polycyclic aromatic hydrocarbons (PAHs in electrocautery smoke during 40 peritonectomy procedures and investigated any correlations and/or differences between levels of PAHs and perioperative variables. Methods. PAHs were measured in personal and stationary sampling by 40 mm Millipore cassettes, for adsorption of both gaseous and particle-bound PAHs. Results. All 16 USEPA priority pollutant PAHs were detected during peritonectomy procedures, naphthalene being the most abundant. For the only two PAHs with Swedish occupational exposure limits (OELs, benzo[a]pyrene and naphthalene, limits were never exceeded. Amount of bleeding was the only perioperative variable that correlated with levels of PAHs. Conclusions. Low levels of PAHs were detected in electrocautery smoke during peritonectomy procedures, and an increased amount of bleeding correlated with higher levels of PAHs. For evaluation of long-term health effects, more studies are needed.

  10. Polycyclic Aromatic Hydrocarbons in Electrocautery Smoke during Peritonectomy Procedures

    Science.gov (United States)

    Näslund Andréasson, Sara; Mahteme, Haile; Sahlberg, Bo; Anundi, Helena

    2012-01-01

    Objective. This study identified and quantified polycyclic aromatic hydrocarbons (PAHs) in electrocautery smoke during 40 peritonectomy procedures and investigated any correlations and/or differences between levels of PAHs and perioperative variables. Methods. PAHs were measured in personal and stationary sampling by 40 mm Millipore cassettes, for adsorption of both gaseous and particle-bound PAHs. Results. All 16 USEPA priority pollutant PAHs were detected during peritonectomy procedures, naphthalene being the most abundant. For the only two PAHs with Swedish occupational exposure limits (OELs), benzo[a]pyrene and naphthalene, limits were never exceeded. Amount of bleeding was the only perioperative variable that correlated with levels of PAHs. Conclusions. Low levels of PAHs were detected in electrocautery smoke during peritonectomy procedures, and an increased amount of bleeding correlated with higher levels of PAHs. For evaluation of long-term health effects, more studies are needed. PMID:22685482

  11. Vitiligo: A study of 120 cases

    Directory of Open Access Journals (Sweden)

    Kar P

    2001-11-01

    Full Text Available Vitiligo is a common pignientary disorder and of major social and cosmetic concern in India. Purpose of the study was to find out age at onset and sex incidence in vitiligo, role of hereditary factors and associations with other diseases. 120 self reporting vitiligo patients attending out patient department of a service hospital were selected for the study and this data was analysed. In the present series out of 120 cases 62 (51.6% were males and 58(48.35%were females. There was practically no difference in sex incidence. The lowest age of onset was two years and the oldest was 65 years. In the majority of patients,52(43.2%, disease started before twenty years of age.8 (6.6% cases gave definite family history of vitiligo. Exposed areas of the body were commonly affected in majority (66.6% of cases. The legs were commonest site of involvement in 60(50% cases. Circunicript type of vitiligo (46.6% was heading the list. Majority of patients (56.6% had multiple lesions. Diabetes mellitus was found in 2 (2.6% patients. Cause of vitiligo is still idiopathic. Hereditary factors hardly play any role in manifestation of vitiligo

  12. Rigour in qualitative case-study research.

    Science.gov (United States)

    Houghton, Catherine; Casey, Dympna; Shaw, David; Murphy, Kathy

    2013-03-01

    To provide examples of a qualitative multiple case study to illustrate the specific strategies that can be used to ensure the credibility, dependability, confirmability and transferability of a study. There is increasing recognition of the valuable contribution qualitative research can make to nursing knowledge. However, it is important that the research is conducted in a rigorous manner and that this is demonstrated in the final research report. A multiple case study that explored the role of the clinical skills laboratory in preparing students for the real world of practice. Multiple sources of evidence were collected: semi-structured interviews (n=58), non-participant observations at five sites and documentary sources. Strategies to ensure the rigour of this research were prolonged engagement and persistent observation, triangulation, peer debriefing, member checking, audit trail, reflexivity, and thick descriptions. Practical examples of how these strategies can be implemented are provided to guide researchers interested in conducting rigorous case study research. While the flexible nature of qualitative research should be embraced, strategies to ensure rigour must be in place.

  13. Interactions between toxic chemicals and natural environmental factors--a meta-analysis and case studies.

    Science.gov (United States)

    Laskowski, Ryszard; Bednarska, Agnieszka J; Kramarz, Paulina E; Loureiro, Susana; Scheil, Volker; Kudłek, Joanna; Holmstrup, Martin

    2010-08-15

    The paper addresses problems arising from effects of natural environmental factors on toxicity of pollutants to organisms. Most studies on interactions between toxicants and natural factors, including those completed in the EU project NoMiracle (Novel Methods for Integrated Risk Assessment of Cumulative Stressors in Europe) described herein, showed that effects of toxic chemicals on organisms can differ vastly depending purely on external conditions. We compiled data from 61 studies on effects of temperature, moisture and dissolved oxygen on toxicity of a range of chemicals representing pesticides, polycyclic aromatic hydrocarbons, plant protection products of bacterial origin and trace metals. In 62.3% cases significant interactions (pnatural factors and chemicals were found, reaching 100% for the effect of dissolved oxygen on toxicity of waterborne chemicals. The meta-analysis of the 61 studies showed that the null hypothesis assuming no interactions between toxic chemicals and natural environmental factors should be rejected at p=2.7 x 10(-82) (truncated product method probability). In a few cases of more complex experimental designs, also second-order interactions were found, indicating that natural factors can modify interactions among chemicals. Such data emphasize the necessity of including information on natural factors and their variation in time and across geographic regions in ecological risk assessment. This can be done only if appropriate ecotoxicological test designs are used, in which test organisms are exposed to toxicants at a range of environmental conditions. We advocate designing such tests for the second-tier ecological risk assessment procedures. Copyright 2010 Elsevier B.V. All rights reserved.

  14. The Pendulum A Case Study in Physics

    CERN Document Server

    Baker, Gregory L

    2005-01-01

    The pendulum: a case study in physics is a unique book in several ways. Firstly, it is a comprehensive quantitative study of one physical system, the pendulum, from the viewpoint of elementary and more advanced classical physics, modern chaotic dynamics, and quantum mechanics. In addition, coupled pendulums and pendulum analogs of superconducting devices are also discussed. Secondly, this book treats the physics of the pendulum within a historical and cultural context,showing, for example, that the pendulum has been intimately connected with studies of the earth's density, the earth's motion,

  15. The Glioma International Case-Control Study

    DEFF Research Database (Denmark)

    Amirian, E. Susan; Armstrong, Georgina N; Zhou, Renke

    2016-01-01

    Decades of research have established only a few etiological factors for glioma, which is a rare and highly fatal brain cancer. Common methodological challenges among glioma studies include small sample sizes, heterogeneity of tumor subtypes, and retrospective exposure assessment. Here, we briefly...... describe the Glioma International Case-Control (GICC) Study (recruitment, 2010-2013), a study being conducted by the Genetic Epidemiology of Glioma International Consortium that integrates data from multiple data collection sites, uses a common protocol and questionnaire, and includes biospecimen...

  16. Case studies of nurseries in Malawi

    DEFF Research Database (Denmark)

    Namoto, M.; Likoswe, M.G.

    This study of 42 case studies of nurseries was made as part of a major sample survey of 360 nurseries in 6 districts in Malawi. The purpose of the study was to let the small nurseries in the country explain in their own words how they source seed, how and for whom they produce seedlings......, and to explain about their problems and opportunities in the nursery business. The assessment was made within the framework of Improved Seed Supply for Agroforestry in African Countries (ISSAAC), a Danida supported programme implemented in cooperation between Forest & Landscape Denmark and World Agroforestry...

  17. Management & Communication: Project Management Case Study

    CERN Multimedia

    Nathalie Dumeaux

    2004-01-01

    We are pleased to announce the recent launch of a new workshop on Project Management. This is designed for People with budgetary, scheduling and/or organizational responsibilities in a project or a sub-project. The objectives through a management case study specially suited to CERN are: to become familiar with modern management techniques in use for structuring, planning, scheduling, costing and progress monitoring of a project or a sub-project. to understand in-depth issues associated with Deliverable-oriented Project Management, Earned Value Management, Advanced Project Cost Engineering and Project Risk Management. The full description of this workshop can be found here. The next session will be held on 8 October 2004. If you are interested in this workshop, please contact Nathalie Dumeaux, email or 78144. Programme of Seminars October to December 2004 Situation : 21.09.2004 Séminaires bilingues Dates Jours Places disponibles Project Management Case study 8 October 1 oui Intr...

  18. Marketing and clinical trials: a case study

    Directory of Open Access Journals (Sweden)

    Entwistle Vikki A

    2007-11-01

    Full Text Available Abstract Background Publicly funded clinical trials require a substantial commitment of time and money. To ensure that sufficient numbers of patients are recruited it is essential that they address important questions in a rigorous manner and are managed well, adopting effective marketing strategies. Methods Using methods of analysis drawn from management studies, this paper presents a structured assessment framework or reference model, derived from a case analysis of the MRC's CRASH trial, of 12 factors that may affect the success of the marketing and sales activities associated with clinical trials. Results The case study demonstrates that trials need various categories of people to buy in – hence, to be successful, trialists must embrace marketing strategies to some extent. Conclusion The performance of future clinical trials could be enhanced if trialists routinely considered these factors.

  19. Marketing and clinical trials: a case study.

    Science.gov (United States)

    Francis, David; Roberts, Ian; Elbourne, Diana R; Shakur, Haleema; Knight, Rosemary C; Garcia, Jo; Snowdon, Claire; Entwistle, Vikki A; McDonald, Alison M; Grant, Adrian M; Campbell, Marion K

    2007-11-20

    Publicly funded clinical trials require a substantial commitment of time and money. To ensure that sufficient numbers of patients are recruited it is essential that they address important questions in a rigorous manner and are managed well, adopting effective marketing strategies. Using methods of analysis drawn from management studies, this paper presents a structured assessment framework or reference model, derived from a case analysis of the MRC's CRASH trial, of 12 factors that may affect the success of the marketing and sales activities associated with clinical trials. The case study demonstrates that trials need various categories of people to buy in - hence, to be successful, trialists must embrace marketing strategies to some extent. The performance of future clinical trials could be enhanced if trialists routinely considered these factors.

  20. Macroprudential Insurance Regulation: A Swiss Case Study

    Directory of Open Access Journals (Sweden)

    Philippe Deprez

    2016-12-01

    Full Text Available This article provides a case study that analyzes national macroprudential insurance regulation in Switzerland. We consider an insurance market that is based on data from the Swiss private insurance industry. We stress this market with several scenarios related to financial and insurance risks, and we analyze the resulting risk capitals of the insurance companies. This stress-test analysis provides insights into the vulnerability of the Swiss private insurance sector to different risks and shocks.

  1. Macroprudential Insurance Regulation: A Swiss Case Study

    OpenAIRE

    Philippe Deprez; Mario V. Wüthrich

    2016-01-01

    This article provides a case study that analyzes national macroprudential insurance regulation in Switzerland. We consider an insurance market that is based on data from the Swiss private insurance industry. We stress this market with several scenarios related to financial and insurance risks, and we analyze the resulting risk capitals of the insurance companies. This stress-test analysis provides insights into the vulnerability of the Swiss private insurance sector to different risks and sho...

  2. Concentrated Photo Voltaics (CPV: a case study

    Directory of Open Access Journals (Sweden)

    Centro S.

    2015-01-01

    Full Text Available Concentrated PhotoVoltaic (CPV, among green energy solutions, nowadays has the ambition to reach grid-parity without subside. CPV substitutes large areas of expensive semiconductor solar cells, with concentrating optics made of cheap materials. Moreover the cells that are suitable for CPV exhibits an unprecedented efficiency and their technology is progressing every year. A case study project, TwinFocus®, will be presented in detail.

  3. Prototype Development and Redesign: A Case Study

    Science.gov (United States)

    1990-03-01

    deal with difficult problems of leadership , strategy and management." [Ref. 10:p. 1] Admiral Turner feels that using the case study method "will help...placement officer was a Lieutenant Commander or Commander. Often times they came from leadership positions of executive officer equivalence. They were...ting power. Personnel within the computer organizatin who are used to manual methods and potential users of the system are resisting the change and

  4. Marketing and clinical trials: a case study

    OpenAIRE

    Entwistle Vikki A; Snowdon Claire; Garcia Jo; Knight Rosemary C; Shakur Haleema; Elbourne Diana R; Roberts Ian; Francis David; McDonald Alison M; Grant Adrian M; Campbell Marion K

    2007-01-01

    Abstract Background Publicly funded clinical trials require a substantial commitment of time and money. To ensure that sufficient numbers of patients are recruited it is essential that they address important questions in a rigorous manner and are managed well, adopting effective marketing strategies. Methods Using methods of analysis drawn from management studies, this paper presents a structured assessment framework or reference model, derived from a case analysis of the MRC's CRASH trial, o...

  5. Private power financing: a case study

    International Nuclear Information System (INIS)

    Stocker, Albert

    1991-01-01

    The Public Utility Regulatory Power Act (PURPA) in the USA and the UK's Electricity Act passed in 1989 are discussed and the first UK private power project is considered. A case study is presented, and covers the questions of when to approach the bank; banker versus investment bank; project fundamentals; the sponsor and the management team; the strength of the key project agreements; syndication of the project debt; and bank support during construction and operation. (author)

  6. Polycyclic Polyprenylated Acylphloroglucinol Congeners Possessing Diverse Structures from Hypericum henryi.

    Science.gov (United States)

    Yang, Xing-Wei; Li, Ming-Ming; Liu, Xia; Ferreira, Daneel; Ding, Yuanqing; Zhang, Jing-Jing; Liao, Yang; Qin, Hong-Bo; Xu, Gang

    2015-04-24

    Polycyclic polyprenylated acylphloroglucinols (PPAPs) are a class of hybrid natural products sharing the mevalonate/methylerythritol phosphate and polyketide biosynthetic pathways and showing considerable structural and bioactive diversity. In a systematic phytochemical investigation of Hypericum henryi, 40 PPAP-type derivatives, including the new compounds hyphenrones G-Q, were obtained. These compounds represent 12 different structural types, including four unusual skeletons exemplified by 5, 8, 10, and 17. The 12 different core structures found are explicable in terms of their biosynthetic origin. The structure of a known PPAP, perforatumone, was revised to hyphenrone A (5) by NMR spectroscopic and biomimetic synthesis methods. Several compounds exhibited inhibitory activities against acetylcholinesterase and human tumor cell lines. This study deals with the structural diversity, function, and biogenesis of natural PPAPs.

  7. Biotransformation of polycyclic aromatic hydrocarbons in marine polychaetes

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Giessing, Anders; Rasmussen, Lene Juel

    2008-01-01

    Deposit-feeding polychaetes constitute the dominant macrofauna in marine environments that tend to be depositional centers for organic matter and contaminants. Polychaetes are known to accumulate polycyclic aromatic hydrocarbons (PAHs) from both particulate and dissolved phases but less is known...... about the mechanisms underlying elimination of accumulated PAHs. An important pathway of elimination is through biotransformation which results in increased aqueous solubility of the otherwise hydrophobic PAHs. Biotransformation in marine polychaetes proceeds in a two phased process similar to those...... well studied in vertebrates, phase I enzymes belonging to the Cytochrome P450 (CYP) enzyme family, along with a few phase II enzymes have been identified in marine polychaetes. In this review we aim at highlighting advances in the mechanistic understanding of PAH biotransformation in marine polychaetes...

  8. Sorption of polycyclic aromatic hydrocarbons on particulate organic matters

    International Nuclear Information System (INIS)

    Guo Xueyan; Luo Lei; Ma Yibing; Zhang Shuzhen

    2010-01-01

    Particulate organic matter (POM) is a key organic matter fraction which can influence soil fertility. Its interactions with hydrophobic organic pollutants (HOCs) have not been characterized and the mechanisms of retention of HOCs by POM remain unclear. In the present study, sorption behaviors of polycyclic aromatic hydrocarbons (PAHs) naphthalene (NAP), phenanthrene (PHE), and pyrene (PYR) by POMs separated from different soils were examined and the POMs were characterized by elemental analysis, solid state 13 C NMR, and Fourier transform infrared spectroscopy (FT-IR). The results indicated that POMs were mainly composed of aliphatic components with high polarity. The different original POMs showed similar chemical composition and configuration. Sorption behaviors of PAHs indicated that there was no significant difference in sorption capacity among the POMs. Sorption of NAP and PHE by POMs displayed a nonlinear isotherm, while sorption of PYR yielded a linear isotherm. No significant hysteresis and ionic strength effect were observed for PAH desorption from the POMs.

  9. Shuttle Transportation System Case-Study Development

    Science.gov (United States)

    Ransom, Khadijah

    2012-01-01

    A case-study collection was developed for NASA's Space Shuttle Program. Using lessons learned and documented by NASA KSC engineers, analysts, and contractors, decades of information related to processing and launching the Space Shuttle was gathered into a single database. The goal was to provide educators with an alternative means to teach real-world engineering processes and to enhance critical thinking, decision making, and problem solving skills. Suggested formats were created to assist both external educators and internal NASA employees to develop and contribute their own case-study reports to share with other educators and students. Via group project, class discussion, or open-ended research format, students will be introduced to the unique decision making process related to Shuttle missions and development. Teaching notes, images, and related documents will be made accessible to the public for presentation of Space Shuttle reports. Lessons investigated included the engine cutoff (ECO) sensor anomaly which occurred during mission STS-114. Students will be presented with general mission infom1ation as well as an explanation of ECO sensors. The project will conclude with the design of a website that allows for distribution of information to the public as well as case-study report submissions from other educators online.

  10. A case series study on complications after breast augmentation with Macrolane™.

    Science.gov (United States)

    Becchere, M P; Farace, F; Dessena, L; Marongiu, Francesco; Bulla, A; Simbula, L; Meloni, G B; Rubino, C

    2013-04-01

    The use of Macrolane™ seems to have several advantages compared to the other standard methods for breast augmentation: it is faster, less invasive, and requires only local anesthesia. Nevertheless, various complications associated with the use of Macrolane™ have been described, e.g., encapsulated lumps in breast tissue, infection, and parenchymal fibrosis. We report the results of our case series study on the clinical and imaging evaluations of patients who came to our attention after breast augmentation with Macrolane™ injection and evaluate the effect of this treatment on breast cancer screening procedures. Between September 2009 and July 2010, seven patients, treated elsewhere with intramammary Macrolane™ injection for cosmetic purposes, presented to our institution complaining of breast pain. In all patients, Macrolane™ had been injected under local anesthesia in the retromammary space through a surgical cannula. On mammography, nodules appeared as gross lobulated radiopacities with polycyclic contours. On breast ultrasound, the nodules showed hypo-anaechogenic cystlike features. In all cases, image analysis by the radiologist was hindered by the presence of the implanted substance, which did not allow the complete inspection of the whole breast tissue. From our experience, although safe in other areas, injection of Macrolane™ into breast tissue cannot be recommended at this time. Our study, along with other reports, supports the need to start a clinical trial on the use of injectable fillers in the breast to validate their safety and effectiveness. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  11. Capturing Cultural Glossaries: Case-study II

    Directory of Open Access Journals (Sweden)

    Matete Madiba

    2011-10-01

    Full Text Available

    ABSTRACT: This case-study attempts to present a brief glossary of Northern Sotho medical terms. It is a follow-up of a similar case-study (Madiba, Mphahlele and Kganyago 2003, which was an attempt to capture and present Northern Sotho cooking terms. Case-study I consists of the names for utensils, ingredients and the processes involved in the preparation of cultural dishes. With both these case-studies, the intention has been to use the opportunities availing themselves for the pres-ervation and valorisation of Northern Sotho, including the extension of its corpora to support national dictionary-making processes. The case-study methodology has been very useful for the purposes of this project and the context within which it was undertaken. It aims to provide a model for the collection and presentation of authentic Northern Sotho terminology which otherwise would hardly have been accessible.

    Keywords: CULTURAL GLOSSARY, INDIGENOUS KNOWLEDGE SYSTEMS, CORPUS, OUTCOMES-BASED EDUCATION, ASSESSMENT CRITERIA, TRADITIONAL MEDICAL TERMS, COMMUNICATIVE APPROACH, STRUCTURAL APPROACH, METONYMY, HANDS-ON ACTIVITIES, TASK-BASED LEARNING

    *****

    OPSOMMING: Die totstandbrenging van kulturele woordversamelings: Ge-vallestudie II. Hierdie gevallestudie probeer om 'n beperkte woordelys van Noord-Sotho- mediese terme aan te bied. Dit is 'n voortsetting van 'n soortgelyke gevallestudie (Madiba, Mpha-hlele en Kganyago 2003 wat 'n poging was om Noord-Sothokookterme te versamel en aan te bied. Gevallestudie I bestaan uit die name van gereedskap, bestanddele, en die prosesse betrokke by die voorbereiding van kulturele geregte. Met altwee hierdie gevallestudies was die bedoeling om die geleenthede te gebruik wat hulleself aanbied vir die bewaring en bestendiging van Noord-Sotho, insluitende die uitbreiding van sy korpora om die nasionale woordeboeksamestellingsprosesse te ondersteun. Die gevallestudiemetodologie was baie nuttig vir die doeleindes van

  12. Physics in Industry: A Case Study

    Science.gov (United States)

    Pratt-Ferguson, Ben

    2007-10-01

    Often ignored and sometimes even considered ``black sheep'' by the university & government-lab physicists, many industrial physicists continue making valuable scientific contributions in diverse areas, from computer science to aero and thermo-dynamics, communications, mathematics, engineering, and simulation, to name a few. This talk will focus on what industrial physicists do, what preparations are beneficial to obtaining a first industrial job, and what the business environment is like for physicists. The case study will be that of the author, starting with undergraduate and graduate studies and continuing on to jobs in industry.

  13. Case studies in atomic collision physics

    CERN Document Server

    McDaniel, Earl Wadsworth

    1972-01-01

    Case Studies in Atomic Collision Physics II focuses on studies on the role of atomic collision processes in astrophysical plasmas, including ionic recombination, electron transport, and position scattering. The book first discusses three-body recombination of positive and negative ions, as well as introduction to ionic recombination, calculation of the recombination coefficient, ions recombining in their parent gas, and three-body recombination at moderate and high gas-densities. The manuscript also takes a look at precision measurements of electron transport coefficients and differential cr

  14. Nanomaterial Case Studies: Nanoscale Titanium Dioxide in ...

    Science.gov (United States)

    EPA announced the availability of the final report, Nanomaterial Case Studies: Nanoscale Titanium Dioxide in Water Treatment and in Topical Sunscreen. This report is a starting point to determine what is known and what needs to be known about selected nanomaterials as part of a process to identify and prioritize research to inform future assessments of the potential ecological and health implications of these materials. Two specific applications of nanoscale titanium dioxide (nano-TiO2) are considered: (1) as an agent for removing arsenic from drinking water; and (2) as an active ingredient in topical sunscreen. These case studies are organized around a comprehensive environmental assessment (CEA) framework that combines a product life cycle perspective with the risk assessment paradigm. They are intended to help identify what may need to be known in order to conduct a comprehensive environmental assessment of the potential risks related to nano-TiO2. These “case studies” do not represent completed or even preliminary assessments, nor are they intended to serve as a basis for risk management decisions in the near term on these specific uses of nano TiO2. Rather, the intent is to use this document in developing the scientific and technical information needed for future assessment efforts.

  15. A Case Study in Corporate Social Responsibility

    Directory of Open Access Journals (Sweden)

    Sharon K. Kendrick

    2014-03-01

    Full Text Available This case study promotes analysis through a brief investigation into the role of corporate social responsibility (CSR in the operation of a multinational corporation as evidenced by Google, Inc. The study focuses on a transnational company in order to observe the impact of CSR practice on a global level. The study will present implications of CSR for corporate management, corporate employees, state regulators, shareholders, and customers in general. In addition, the study will discuss consequences of poor CSR compliance for a multinational corporation. Questions for analysis include implications of CSR, employee retention, development of corporate culture, and evaluation of advantages and disadvantages of different CSR approaches. Upon conclusion of the study, suggestions are made for future collaborative efforts in corporate social responsibility as applied to psychological, sociological, and economical motives. Recruiting and training possibilities also present partnership opportunities for best practice sharing in regards to community, civic, and service engagement.

  16. Terahertz applications in cultural heritage: case studies

    Science.gov (United States)

    Giovannacci, D.; Martos-Levif, D.; Walker, G. C.; Menu, M.; Detalle, V.

    2013-11-01

    Terahertz (THz) spectroscopy and imaging is a non-destructive, non-contact, non-invasive technology emerging as a tool for the analysis of cultural heritage. THz Time Domain Spectroscopy (TDS) techniques have the ability to retrieve information from different layers within a stratified sample, that enable the identification of hidden sub-layers in the case of paints and mural paintings. In this paper, we present the THz TDS2 system developed in the European Commission's 7th Framework Program project CHARISMA [grant agreement no. 228330]. Bespoke single processing algorithms; including a deconvolution algorithm can be deployed to increase the resolution and the global performance of the system. The potential and impact of this work is demonstrated through two case studies of mural paintings, where the capability to reveal the stratigraphy of the artworks is demonstrated.

  17. The case study of biomaterials and biominerals

    Science.gov (United States)

    Del Hoyo Martínez, Carmen

    2013-04-01

    The teaching of biomaterials as case study by on-line platform , susceptible to develop both individually and in groups, got different objectives proposed by the European Higher Education System, among which include: participate actively in the teaching-learning process by students, interpreting situations, adapt processes and solutions. It also improves oral and written communication, analytical skills and synthesis and also the ability to think critically. Biomaterials have their origin in biominerals. These are solid inorganic compounds of defined structure, consisting of molecular control mechanisms that operate in biological systems. Its main functions are: structural support, a reservoir of essential elements, sensors, mechanical protection and storage of toxic elements. Following the demand of materials compatible with certain functional systems of our body, developed biomaterials. Always meet the condition of biocompatibility. Should be tolerated by the body and do not provoke rejection. This involves a comprehensive study of physiological conditions and the anatomy of the body where a biomaterial has to be implemented. The possibility of generating new materials from biominerals has a major impact in medicine and other fields could reach as geology, construction, crystallography, etc. While the study of these issues is in its infancy today, can be viewed as an impact on the art and future technology. Planning case study that students would prepare its report for discussion in subgroups. Occurs then the pooling of individual analysis, joint case discussion and adoption by the subgroup of a consensual solution to the problem. The teacher as facilitator and coordinator of the final case analysis, sharing leads to group-wide class and said the unanimous decision reached by the students and gives his opinion on the resolution of the case. REFERENCES D.P. Ausubel. Psicología Educativa. Un punto de vista cognoscitivo. Trillas. Ed. 1983. E.W. Eisner. Procesos

  18. Using Case Studies to Teach About Global Issues, Bali: A Case Study

    Science.gov (United States)

    Oswald, James M.

    1974-01-01

    The South Pacific island of Bali is used as a case study of overpopulation and food shortage. A brief description of the resources, the typical lifestyle of the Balinese farmer, and possible teaching techniques are given. (DE)

  19. THE INFRARED SPECTROSCOPY OF POLYCYCLIC AROMATIC HYDROCARBONS WITH FIVE- AND SEVEN-MEMBERED FUSED RING DEFECTS

    International Nuclear Information System (INIS)

    Ricca, Alessandra; Bauschlicher, Charles W. Jr; Allamandola, Louis J.

    2011-01-01

    Polycyclic aromatic hydrocarbon (PAH) growth and destruction are thought to proceed via the occasional incorporation of five- and seven-membered fused ring defects in the hexagonal carbon skeleton. Using density functional theory, this paper investigates the effect such five- and seven-membered fused ring defects have on the infrared spectra of ovalene, circumovalene, and circumcircumovalene. The defects make only small changes to the overall infrared (IR) spectra, both in the mid-IR and in the far-IR, of these species. In addition to small shifts in the positions of the bands between the PAHs with and without defects, the most common effect of the defects is to increase the number of bands. Except for an anion with the Stone-Wales defect, all of the species studied have the C-C stretching band at 6.3 μm or at longer wavelengths, the position in Classes B and C astronomical PAH spectra. In the case of the Stone-Wales anion, the band falls at 6.20 μm, suggesting that further study of defects is probably worthwhile, as some PAHs with defects might be important in those sources (Class A) that show a C-C stretching band that falls near 6.2 μm.

  20. Assessing the polycyclic aromatic hydrocarbon (PAH) pollution of urban stormwater runoff: a dynamic modeling approach.

    Science.gov (United States)

    Zheng, Yi; Lin, Zhongrong; Li, Hao; Ge, Yan; Zhang, Wei; Ye, Youbin; Wang, Xuejun

    2014-05-15

    Urban stormwater runoff delivers a significant amount of polycyclic aromatic hydrocarbons (PAHs), mostly of atmospheric origin, to receiving water bodies. The PAH pollution of urban stormwater runoff poses serious risk to aquatic life and human health, but has been overlooked by environmental modeling and management. This study proposed a dynamic modeling approach for assessing the PAH pollution and its associated environmental risk. A variable time-step model was developed to simulate the continuous cycles of pollutant buildup and washoff. To reflect the complex interaction among different environmental media (i.e. atmosphere, dust and stormwater), the dependence of the pollution level on antecedent weather conditions was investigated and embodied in the model. Long-term simulations of the model can be efficiently performed, and probabilistic features of the pollution level and its risk can be easily determined. The applicability of this approach and its value to environmental management was demonstrated by a case study in Beijing, China. The results showed that Beijing's PAH pollution of road runoff is relatively severe, and its associated risk exhibits notable seasonal variation. The current sweeping practice is effective in mitigating the pollution, but the effectiveness is both weather-dependent and compound-dependent. The proposed modeling approach can help identify critical timing and major pollutants for monitoring, assessing and controlling efforts to be focused on. The approach is extendable to other urban areas, as well as to other contaminants with similar fate and transport as PAHs. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Describing Case Study Method and Identifying the Factors that Contribute to the Successful Conduct of Case Studies

    OpenAIRE

    Ahmad H. Juma'h; Mustafa Cavus

    2001-01-01

    This article has attempted to describe case study, the limitations and critiques on case study methodology and how the proponents have responded to these. Our special focus have been on the debate on theory building from case study research, and a framework for conducting case study research as well as the factors for a successful case study research. The overall conclusion is that the case study has been inappropriately used to generate theories.

  2. Present status and problems of radionuclide studies in emergency cases

    International Nuclear Information System (INIS)

    Ogawa, Kiyoshi

    1983-01-01

    Scintigraphy is just right for diagnosing emergency cases due to its noninvasive and simple method, but emergency radionuclide studies have not become practical as a result of difficulty problems. Recently, nuclear medical devices have become easier to use in operations. It is become of this, that I have submitted this report regarding the problems of radionuclide studies in emergency cases. There were 101 cases (1.4 %) out of 7,310 cases for the year period Sept. 1981 - Aug. 1982. The studies consisted of 12 brain imaging cases, 9 plumonary imaging cases, 22 cardiac study cases (cardio-angiography cases 8, 99m-Tc-PYP myocardium imaging cases 12, 201-Tl myocardium imaging cases 2), 12 renal study cases, 11 G.I. blood loss cases, 35 peripheral angiography cases. In the near future, we will have to be ready to perform emergency radionuclide studies if the need arises. (author)

  3. Antifungal activity of polycyclic aromatic hydrocarbons against Ligninolytic fungi

    Directory of Open Access Journals (Sweden)

    Memić Mustafa

    2011-01-01

    Full Text Available Environmental contamination by polycyclic aromatic hydrocarbons (PAHs has caused increasing concern because of their known, or suspected, carcinogenic and mutagenic effects. Polycyclic aromatic hydrocarbons occurring in the environment are usually the result of the incomplete combustion of carbon containing materials. The main sources of severe PAHs contamination in soil come from fossil fuels, i.e. production or use of fossil fuels or their products, such as coal tar and creosote. Creosote is used as a wood preservation for railway ties, bridge timbers, pilling and large-sized lumber. It consists mainly of PAHs, phenol and cresol compounds that cause harmful health effects. Research on biodegradation has shown that a special group of microorganisms, the white-rot fungi and brown-rot fungi, has a remarkable potential to degrade PAHs. This paper presents a study of the antifungal activity of 12 selected PAHs against two ligninolytic fungi Hypoxylon fragiforme (white rot and Coniophora puteana (brown rot. The antifungal activity of PAHs was determined by the disc-diffusion method by measuring the diameter of the zone of inhibition. The results showed that the antifungal activity of the tested PAHs (concentration of 2.5 mmol/L depends on the their properties such as molar mass, solubility in water, values of log Kow, ionization potential and Henry’s Law constant as well as number of aromatic rings, molecule topology or pattern of ring linkage. Among the 12 investigated PAHs, benzo(k fluoranthene with five rings, and pyrene with four cyclic condensed benzene rings showed the highest antifungal activity.

  4. Putting Words in Their Mouth: Writing Dialogue for Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman

    2018-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This issue discusses dialogue writing guidelines most relevant to case writing.

  5. Deep Attack Weapons Mix Study (DAWMS) Case Study

    National Research Council Canada - National Science Library

    Bexfield, James

    2001-01-01

    .... This report describes the process used to conduct the Deep Attack Weapons Mix Study (DAWMS) in 1995-1997. This case study focuses on the weapons being procured by the Services and whether a joint viewpoint would result in a more effective mix...

  6. Case-Control Studies - An Efficient Observational Study Design

    NARCIS (Netherlands)

    van Stralen, Karlijn J.; Dekker, Friedo W.; Zoccali, Carmine; Jager, Kitty J.

    2010-01-01

    Case-control studies are an efficient research method for investigating risk factors of a disease. The method involves the comparison of the odds of exposure in a patient group with that of the odds of exposure in a control group. As only a minority of the population is included in the study, less

  7. A Case Study Application Of Time Study Model In Paint ...

    African Journals Online (AJOL)

    This paper presents a case study in the development and application of a time study model in a paint manufacturing company. The organization specializes in the production of different grades of paint and paint containers. The paint production activities include; weighing of raw materials, drying of raw materials, dissolving ...

  8. Case studies in organic contaminant hydrogeology

    International Nuclear Information System (INIS)

    Baker, J.A.

    1989-01-01

    The effective management of domestic solid waste and hazardous, toxic, and radioactive waste is a major problem in the area of environmental geology and water sciences throughout the world. A series of case studies is presented of organic contaminants from both solid and hazardous waste disposal facilities to provide examples of these problems. The facilities were investigated to determine risks and liabilities before acquisition, to determine the site hydrogeologic conditions for design of appropriate groundwater monitoring plans, and/or to determine the potential for groundwater contamination. The case studies are of disposal facilities located in glacial tills, carbonaceous weathered clay soils, weathered shale, limestone bedrock, dolomite bedrock, and alluvial and sedimentary deposits. The results of these studies and investigations show certain relationships in the distribution of organic pollutants to the different geologic and hydrogeologic characteristics of each facility. In each of the four case studies, all 129 priority pollutants were analyzed in private wells and/or monitoring wells. The 31 volatile organic compounds (VOCs) of the priority pollutant list were the majority of organic compounds detected. When VOCs are found in groundwater impacted by disposal facilities, they are present in groups and tend to be distributed in patterns based on their relative concentrations. It is rare to find only one or two VOCs from facilities where leakage has been detected. The ethylenes and ethanes appear to be more prevalent and mobile than aromatic VOCs. The aromatics are restricted primarily to leachates and wastes and in monitoring wells located adjacent to facilities. 2 refs., 15 figs

  9. Mathematical modelling a case studies approach

    CERN Document Server

    Illner, Reinhard; McCollum, Samantha; Roode, Thea van

    2004-01-01

    Mathematical modelling is a subject without boundaries. It is the means by which mathematics becomes useful to virtually any subject. Moreover, modelling has been and continues to be a driving force for the development of mathematics itself. This book explains the process of modelling real situations to obtain mathematical problems that can be analyzed, thus solving the original problem. The presentation is in the form of case studies, which are developed much as they would be in true applications. In many cases, an initial model is created, then modified along the way. Some cases are familiar, such as the evaluation of an annuity. Others are unique, such as the fascinating situation in which an engineer, armed only with a slide rule, had 24 hours to compute whether a valve would hold when a temporary rock plug was removed from a water tunnel. Each chapter ends with a set of exercises and some suggestions for class projects. Some projects are extensive, as with the explorations of the predator-prey model; oth...

  10. Prayer Healing: A Case Study Research Protocol.

    Science.gov (United States)

    Kruijthoff, Dirk J; van der Kooi, Cornelis; Glas, Gerrit; Abma, Tineke A

    2017-01-01

    Context • Prayer healing is a common practice in many religious communities around the world. Even in the highly secularized Dutch society, cases of prayer healing are occasionally reported in the media, often generating public attention. There is an ongoing debate regarding whether such miraculous cures do actually occur and how to interpret them. Objective • The aim of the article was to present a research protocol for the investigation of reported cases of remarkable and/or unexplained healing after prayer. Design • The research team developed a method to perform a retrospective, case-based study of prayer healing. Reported prayer healings can be investigated systematically in accordance with a step-by-step methodology. The focus is on understanding the healing by studying it from multiple perspectives, using both medical judgment and patients' narratives collected by qualitative methods Setting • The study occurred at Vrije Universiteit (VU) and VU Medical Center (Amsterdam, Netherlands) as well as the general medical practice of the first author. Participants • Potential participants could be any individuals in the Netherlands or neighboring countries who claim to have been healed through prayer. The reports of healing came from multiple sources, including the research team's medical practices and their direct vicinities, newspaper articles, prayer healers, and medical colleagues. Outcome Measures • Medical data were obtained before and after prayer. Subsequently, a member of a research team and of a medical assessment committee made a standardized judgment that evaluated whether a cure was clinically remarkable or scientifically unexplained. The participants' experiences and insider perspectives were studied, using in-depth interviews in accordance with a qualitative research methodology, to gain insight into the perceptions and explanations of the cures that were offered by participants and by the members of the medical assessment committee. The

  11. Microbial degradation of monocyclic and polycyclic aromatic hydrocarbons in case of limited pollutant availability with nitrate as a potential electron acceptor; Der mikrobielle Abbau mono- und polyzyklischer aromatischer Kohlenwasserstoffe bei einer begrenzten Schadstoffverfuegbarkeit mit Nitrat als potentiellem Elektronenakzeptor

    Energy Technology Data Exchange (ETDEWEB)

    Linke, C.

    2001-07-01

    The possibility of using natural degradation processes for long-term remediation of tar oil contaminated sites was investigated. Field studies have shown that microbial decomposition of pollutants does take place in many sites but that it is limited by limited availability of pollutants and oxygen in soil. The investigations focused on the activation of BTEX and PAH degradation in situ by nitrate in the absence or in the presence of oxygen. Tensides should be used in order to enhance the availability of pollutants in water, especially in the case of hardly water-soluble PAH. A large-scale experiment was carried out on tar oil contaminated terrain; it was found that the availability of oxygen and not of PAH is the limiting factor so that adding of surfactants will not improve pollutant degradation. In contrast, the adding of tensides would mean even higher concentrations of oxygen-depleting substances in soil. [German] In der vorliegenden Arbeit wurden im Hinblick auf langfristige Sanierungsstrategien fuer teeroelkontaminierte Standorte Moeglichkeiten der Nutzung natuerlicher Abbauvorgaenge untersucht. Zahlreiche Feldstudien belegen, dass ein mikrobieller Schadstoffabbau an vielen Standorten stattfindet, dieser jedoch sowohl durch eine begrenzte Schadstoffverfuegbarkeit als auch durch den im Untergrund nur begrenzt zur Verfuegung stehenden Sauerstoff limitiert wird. Ziel dieser Arbeit war es abzuklaeren, inwiefern ein BTEX- und PAK-Abbau in situ auch in Abwesenheit von Sauerstoff durch Nitrat allein oder durch Nitrat in Kombination mit Sauerstoff aktiviert werden kann. Um insbesondere fuer die schlecht wasserloeslichen PAK eine ausreichende Schadstoffverfuegbarkeit zu gewaehrleisten, sollten auch Tenside zur Erhoehung der im Wasser vorliegenden Schadstoffmenge eingesetzt werden. Aufbauend auf die Laboruntersuchungen wurde im Rahmen von VEGAS{sup ix} ein Grossversuch zum mikrobiellen PAK-Abbau im Abstrom einer simulierten Teeroelkontamination durchgefuehrt

  12. Bioconcentration and acute toxicity of polycyclic musks in two benthic organisms (Chironomus riparius and Lumbriculus variegatus)

    NARCIS (Netherlands)

    Artola-Garicano, E.; Sinnige, T.L.; Holsteijn, I. van; Vaes, W.H.J.; Hermens, J.L.M.

    2003-01-01

    In the current study, the bioconcentration behavior and acute toxicity of two polycyclic musks, Tonalide® 7-acetyl-1,1,3,4,4,6,-hexamethyl-1,2,3,4,-tetrahydronaphthalene (AHTN) and Galaxolide® 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexa-methyl-cyclopenta[γ]-2- benzopyran (HHCB), were studied in two

  13. Concentration of polycyclic aromatic hydrocarbons in water samples from different stages of treatment

    Science.gov (United States)

    Pogorzelec, Marta; Piekarska, Katarzyna

    2017-11-01

    The aim of this study was to analyze the presence and concentration of selected polycyclic aromatic hydrocarbons in water samples from different stages of treatment and to verify the usefulness of semipermeable membrane devices for analysis of drinking water. For this purpose, study was conducted for a period of 5 months. Semipermeable membrane devices were deployed in a surface water treatment plant located in Lower Silesia (Poland). To determine the effect of water treatment on concentration of PAHs, three sampling places were chosen: raw water input, stream of water just before disinfection and treated water output. After each month of sampling SPMDs were changed for fresh ones and prepared for further analysis. Concentrations of fifteen polycyclic aromatic hydrocarbons were determined by high performance liquid chromatography (HPLC). Presented study indicates that the use of semipermeable membrane devices can be an effective tool for the analysis of aquatic environment, including monitoring of drinking water, where organic micropollutants are present at very low concentrations.

  14. Wind to Hydrogen in California: Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Antonia, O.; Saur, G.

    2012-08-01

    This analysis presents a case study in California for a large scale, standalone wind electrolysis site. This is a techno-economic analysis of the 40,000 kg/day renewable production of hydrogen and subsequent delivery by truck to a fueling station in the Los Angeles area. This quantity of hydrogen represents about 1% vehicle market penetration for a city such as Los Angeles (assuming 0.62 kg/day/vehicle and 0.69 vehicles/person) [8]. A wind site near the Mojave Desert was selected for proximity to the LA area where hydrogen refueling stations are already built.

  15. Case study: Bioremediation in the Aleutian Islands

    International Nuclear Information System (INIS)

    Steward, K.J.; Laford, H.D.

    1995-01-01

    This case study describes the design, construction, and operation of a bioremediation pile on Adak Island, which is located in the Aleutian Island chain. Approximately 1,900 m 3 of petroleum-contaminated soil were placed in the bioremediation pile. The natural bioremediation process was enhanced by an oxygen and nutrient addition system to stimulate microbial activity. Despite the harsh weather on the island, after the first 6 months of operation, laboratory analyses of soil samples indicated a significant (80%) reduction in diesel concentrations

  16. Reinforcement learning: Solving two case studies

    Science.gov (United States)

    Duarte, Ana Filipa; Silva, Pedro; dos Santos, Cristina Peixoto

    2012-09-01

    Reinforcement Learning algorithms offer interesting features for the control of autonomous systems, such as the ability to learn from direct interaction with the environment, and the use of a simple reward signalas opposed to the input-outputs pairsused in classic supervised learning. The reward signal indicates the success of failure of the actions executed by the agent in the environment. In this work, are described RL algorithmsapplied to two case studies: the Crawler robot and the widely known inverted pendulum. We explore RL capabilities to autonomously learn a basic locomotion pattern in the Crawler, andapproach the balancing problem of biped locomotion using the inverted pendulum.

  17. Case study of nuclear power planning

    International Nuclear Information System (INIS)

    Covarrubias, A.J.; Lane, J.A.

    1976-01-01

    An improved version of the computer programme WASP (Wien Automatic System Planning) is described by the example of a case study. The aim of an optimal power plant development within the economic development is reached over several steps the most important parameters of which are explained in detail. To use the method it is necessary to know and to describe the energy and electricity supply situation of the country referred to. The programme development described has proved to be good in use in an international frame. The IAEA offers its help to all prospected customers in their initial period with the programme WASP. (UA) [de

  18. Makerspaces in Engineering Education: A Case Study

    DEFF Research Database (Denmark)

    Jensen, Lasse Skovgaard; Özkil, Ali Gürcan; Mougaard, Krestine

    2016-01-01

    it by opening makerspaces and adopting elements of the Maker Movement in their offerings. This paper investigates how university driven makerspaces can affect engineering design and product development education trough a case study. We provide our findings based on interviews and data collected from educators......, students the administrative and workshop staff of the makerspace. The findings are used to outline the challenges in incorporating the offerings of makerspaces. By discussing these challenges we identify opportunities for turning university makerspaces into innovation hubs and platforms that can support...

  19. Russian Media Educators: Case Studies Portraits

    Directory of Open Access Journals (Sweden)

    Alexander Fedorov

    2013-01-01

    Full Text Available This article is devoted to case studies of the media education works of some well knowns Russian media educators. The analysis of media educational work of the famous Russian media educators leads us to the conclusion that media education in Russia is developing, building on the synthesis of the aesthetic, socio-cultural, and practical concepts, with a focus on the development of media competence of the audience, mainly school and youth. The enthusiasts of media education, even devoid of substantial public support for its innovative projects, achieve significant and meaningful results.

  20. Metrology in Pharmaceutical Industry - A Case Study

    International Nuclear Information System (INIS)

    Yuvamoto, Priscila D.; Fermam, Ricardo K. S.; Nascimento, Elizabeth S.

    2016-01-01

    Metrology is recognized by improving production process, increasing the productivity, giving more reliability to the measurements and consequently, it impacts in the economy of a country. Pharmaceutical area developed GMP (Good Manufacture Practice) requeriments, with no introduction of metrological concepts. However, due to Nanomedicines, it is expected this approach and the consequent positive results. The aim of this work is to verify the level of metrology implementation in a Brazilian pharmaceutical industry, using a case study. The purpose is a better mutual comprehension by both areas, acting together and governmental support to robustness of Brazilian pharmaceutical area. (paper)

  1. Myonecrosis in Sickle Cell Anemia: Case Study.

    Science.gov (United States)

    Turaga, Lalita Prabha; Boddu, Prajwal; Kipferl, Steve; Basu, Anupam; Yorath, Martin

    2017-01-30

    BACKGROUND Myonecrosis is one of the more poorly studied, painful manifestations of sickle cell crisis. Medical literature is sparse detailing the manifestations and management of such symptoms. In myonecrosis, red cells containing sickle hemoglobin become rigid, resulting in reduced blood flow and myonecrosis. CASE REPORT We present a case study of a patient in sickle cell crisis with an episode of acute pain and swelling to the intrinsic muscles of the foot as a prominent feature of the crises. Although muscle biopsy is considered the gold standard for the diagnosis of myositis or myonecrosis, a low intensity signal on T1 and high intensity signal on T2 at the affected muscle belly can be as conclusive as imaging studies. In an actively sickling patient any invasive intervention should be avoided as it can result in ischemic necrosis of the tissues, due to interruption of capillary flow in end-arteries. CONCLUSIONS Early recognition is critical in sickle cell disease management, allowing for prompt and aggressive fluid resuscitation which remains a cornerstone in the management of most sickle cell vaso-occlusive crises. In this instance, off loading the extremity and early fluid resuscitation resolved the pain and swelling and prevented myonecrosis.

  2. The chemistry of the polycyclic polyprenylated acylphloroglucinols.

    Science.gov (United States)

    Richard, Jean-Alexandre; Pouwer, Rebecca H; Chen, David Y-K

    2012-05-07

    With their fascinating biological profiles and stunningly complex molecular architectures, the polycyclic polyprenylated acylphloroglucinols (PPAPs) have long provided a fertile playing field for synthetic organic chemists. In particular, the recent advent of innovative synthetic methods and strategies together with C-C bond-forming reactions and asymmetric catalysis have revitalized this field tremendously. Consequently, PPAP targets which once seemed beyond reach have now been synthesized. This Review aims to highlight the recent achievements in the total synthesis of PPAPs, as well as notable methods developed for the construction of the bicyclo[3.3.1] core of these chemically and biologically intriguing molecules. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Polycyclic aromatic hydrocarbons (PAHs) in yogurt samples.

    Science.gov (United States)

    Battisti, Chiara; Girelli, Anna Maria; Tarola, Anna Maria

    2015-01-01

    The concentrations and distributions of major polycyclic aromatic hydrocarbons (PAHs) were determined in 20 kinds of yogurt specimens collected from Italian supermarkets using reversed phase high-performance liquid chromatography equipped with fluorescence detection. The method was validated by determination of recovery percentages, precision (repeatability) and sensitivity (limits of detection) with yogurt samples fortified at 0.25, 0.5 and 1 µg/kg concentration levels. The recovery of 13 PAHs, with the exception of naphthalene and acenaphthene, ranged from 61% to 130% and from 60% to 97% at all the levels for yogurts with low (0.1%) and high (3.9%) fat content, respectively. The method is repeatable with relative standard deviation values yogurts with low and high fats were compared.

  4. Emission factors of polycyclic and nitro-polycyclic aromatic hydrocarbons from residential combustion of coal and crop residue pellets.

    Science.gov (United States)

    Yang, Xiaoyang; Liu, Shijie; Xu, Yisheng; Liu, Yu; Chen, Lijiang; Tang, Ning; Hayakawa, Kazuichi

    2017-12-01

    Polycyclic aromatic hydrocarbons (PAHs) and nitro-polycyclic aromatic hydrocarbons (NPAHs) are toxic pollutants mainly produced during fossil fuel combustion. Domestic coal stoves, which emit large amounts of PAHs and NPAHs, are widely used in the Chinese countryside. In this study, emission factors (Efs) for 13 PAH species and 21 NPAH species for four raw coal (three bituminous and one anthracite), one honeycomb briquette, and one crop residue pellet (peanut hulls) samples burned in a typical Chinese rural cooking stove were determined experimentally. The PAH and NPAH Efs for the six fuels were 3.15-49 mg/kg and 0.32-100 μg/kg, respectively. Peanut hulls had very high Efs for both PAHs and NPAHs, and honeycomb briquettes had the lowest Efs. 2-Nitropyrene and 2-nitrofluoranthene, which are NPAHs typically found in secondary organic aerosol, were detected in the emissions from some fuels, suggesting that chemical reactions may have occurred in the dilution tunnel between the flue gas leaving the stove and entering the sampler. The 1-nitropyrene to pyrene diagnostic ratios for coal and peanut hulls were 0.0001 ± 0.0001 and 0.0005, respectively. These were in the same order of magnitude as reference ratios for emissions during coal combustion. The 6-nitrobenzo[a]pyrene to benzo[a]pyrene ratios for the fuels were determined, and the ratios for coal and peanut hulls were 0.0010 ± 0.0001 and 0.0014, respectively. The calculated potential toxic risks indicated that peanut hull emissions were very toxic, especially in terms of NPAHs, compared with emissions from the other fuels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Δg: The new aromaticity index based on g-factor calculation applied for polycyclic benzene rings

    Science.gov (United States)

    Ucun, Fatih; Tokatlı, Ahmet

    2015-02-01

    In this work, the aromaticity of polycyclic benzene rings was evaluated by the calculation of g-factor for a hydrogen placed perpendicularly at geometrical center of related ring plane at a distance of 1.2 Å. The results have compared with the other commonly used aromatic indices, such as HOMA, NICSs, PDI, FLU, MCI, CTED and, generally been found to be in agreement with them. So, it was proposed that the calculation of the average g-factor as Δg could be applied to study the aromaticity of polycyclic benzene rings without any restriction in the number of benzene rings as a new magnetic-based aromaticity index.

  6. The Composition of Cigarette Smoke. An Historical Perspective of Several Polycyclic Aromatic Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Rodgman A

    2014-12-01

    Full Text Available Because of the significant advancements in fractionation, analytical, and characterization technologies since the early 1960s, hundreds of components of complex mixtures have been accurately characterized without the necessity of actually isolating the individual component. This has been particularly true in the case of the complex mixtures tobacco and tobacco smoke. Herein, an historical account of a mid-1950 situation concerning polycyclic aromatic hydrocarbons (PAHs in cigarette smoke is presented. While the number of PAHs identified in tobacco smoke has escalated from the initial PAH, azulene, identified in 1947 to almost 100 PAHs identified by late 1963 to more than 500 PAHs identified by the late 1970s, the number of PAHs isolated individually and characterized by several of the so-called classical chemical means (melting point, mixture melting point, derivative preparation and properties in the mid-1950s and since is relatively few, 14 in all. They were among 44 PAHs identified in cigarette mainstream smoke and included the following PAHs ranging from bicyclic to pentacyclic: Acenaphthylene, 1,2-dihydroacenaphthylene, anthracene, benz[a]anthracene, benzo[a]pyrene, chrysene, dibenz[a, h]anthracene, fluoranthene, 9H-fluorene, naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, phenanthrene, and pyrene. One of them, benzo[a]pyrene, was similarly characterized in another study in 1959 by Hoffmann.

  7. ON ESTIMATING INTERSTELLAR POLYCYCLIC AROMATIC HYDROCARBON ABUNDANCES WITH CALCULATED OSCILLATOR STRENGTHS

    International Nuclear Information System (INIS)

    Tan Xiaofeng; Bernstein, Lawrence; Cami, Jan; Salama, Farid

    2011-01-01

    Vibronic bands of polycyclic aromatic hydrocarbons (PAHs) in the UV/visible range are often used to estimate the abundances of PAHs in the interstellar medium by comparing laboratory-measured spectra with astronomical observations. We investigate the errors introduced by associating theoretical electronic oscillator strengths with individual vibronic bands when estimating the abundances of interstellar PAHs. The vibronic oscillator strengths of the 0-0 bands of nine PAHs with two to seven benzene rings, spanning in the 2800-6700 A spectral range, have been calculated using the Franck-Condon approximation and compared to their electronic oscillator strengths. It is found that the use of calculated electronic oscillator strengths rather than the more physically relevant vibronic oscillator strengths underestimates interstellar abundances of the nine PAHs under study, on average by a factor of about 2.4. It is recommended that vibronic oscillator strengths should be systematically used to analyze the vibronic spectra of specific PAHs and to estimate their abundances in the interstellar medium. An empirical correcting factor is suggested for the cases where the vibronic oscillator strengths are unknown for more realistic estimation of interstellar PAH abundances.

  8. Parsing pyrogenic polycyclic aromatic hydrocarbons: forensic chemistry, receptor models, and source control policy.

    Science.gov (United States)

    O'Reilly, Kirk T; Pietari, Jaana; Boehm, Paul D

    2014-04-01

    A realistic understanding of contaminant sources is required to set appropriate control policy. Forensic chemical methods can be powerful tools in source characterization and identification, but they require a multiple-lines-of-evidence approach. Atmospheric receptor models, such as the US Environmental Protection Agency (USEPA)'s chemical mass balance (CMB), are increasingly being used to evaluate sources of pyrogenic polycyclic aromatic hydrocarbons (PAHs) in sediments. This paper describes the assumptions underlying receptor models and discusses challenges in complying with these assumptions in practice. Given the variability within, and the similarity among, pyrogenic PAH source types, model outputs are sensitive to specific inputs, and parsing among some source types may not be possible. Although still useful for identifying potential sources, the technical specialist applying these methods must describe both the results and their inherent uncertainties in a way that is understandable to nontechnical policy makers. The authors present an example case study concerning an investigation of a class of parking-lot sealers as a significant source of PAHs in urban sediment. Principal component analysis is used to evaluate published CMB model inputs and outputs. Targeted analyses of 2 areas where bans have been implemented are included. The results do not support the claim that parking-lot sealers are a significant source of PAHs in urban sediments. © 2013 SETAC.

  9. Case Study: Puttin' on the Ritz: How to Put Science into Cases

    Science.gov (United States)

    Herreid, Clyde Freeman

    2017-01-01

    There are multiple ways to put science into a case. This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses different ways of presenting science in case studies.

  10. Does the concept of Clar's aromatic sextet work for dicationic forms of polycyclic aromatic hydrocarbons?--testing the model against charged systems in singlet and triplet states.

    Science.gov (United States)

    Dominikowska, Justyna; Palusiak, Marcin

    2011-07-07

    The concept of Clar's π-electron aromatic sextet was tested against a set of polycyclic aromatic hydrocarbons in neutral and doubly charged forms. Systems containing different types of rings (in the context of Clar's concept) were chosen, including benzene, naphthalene, anthracene, phenanthrene and triphenylene. In the case of dicationic structures both singlet and triplet states were considered. It was found that for singlet state dicationic structures the concept of aromatic sextet could be applied and the local aromaticity could be discussed in the context of that model, whereas in the case of triplet state dicationic structures Clar's model rather failed. Different aromaticity indices based on various properties of molecular systems were applied for the purpose of the studies. The discussion about the interdependence between the values of different aromaticity indices applied to neutral and charged systems in singlet and triplet states is also included. This journal is © the Owner Societies 2011

  11. Formation of polycyclic aromatic hydrocarbons by ionizing radiations

    International Nuclear Information System (INIS)

    Perez, G.; Lilia, E.; Cristalli, A.

    1986-01-01

    Gaseous 0-terphenyl, 1-phenylnaphthalene, and 9-phenylanthracene were submitted to gamma rays. The yields of cyclization products, polycyclic aromatic hydrocarbons, show that at least one twentieth of the intermediates formed undergo intramolecular reaction. (author)

  12. Distribution of polycyclic aromatic hydrocarbons in rural agricultural ...

    African Journals Online (AJOL)

    AJB SERVER

    African Journal of Biotechnology Vol. 5 (15), pp. 1415-1421, 3 August 2006 ... Polycyclic aromatic hydrocarbons (PAHs) are a group of chemicals that are formed during ... site for refinery process wastes, which has been operated since 1958 ...

  13. A postural `stressed` cerebral HMPAO case study

    Energy Technology Data Exchange (ETDEWEB)

    Williams, R.C.; Jost, G.M.; Bolitho, L.; Grantham, M. [Wangaratta District Hospital, VIC (Australia)

    1998-03-01

    Full text: This case study represents an example of the utility of postural hypoperfusion stressed HMPAO SPECT. An elderly woman of 78 with a long history of giddiness was referred to our laboratory for examination of possible cerebral ischaemia. She had recurrent dizzy episodes, sometimes posture related, over the past few years and had suffered several falls. Cerebral DSA revealed minimal disease. CT scans were reported as normal. Carotid duplex Doppler studies revealed bilateral plaque disease in the carotid bulbs extending to the origins of the ICAs which were not significant stenoses. Postural symptoms were induced by standing the patient up rapidly and HMPAO was administered at the same time. A SPECT scan of the brain was performed. Quantitative analysis showed a left to right decrease of 10.8% in the temporo-occipital area, 5.6% in the temporo-parietal area and 2.5% in the cerebellar and parietal areas. Images revealed moderately reduced tracer concentration in the left half of the cerebellum and the left occipital region extending as far forward as the temporo-parietal region A repeat HMPAO SPECT scan without stress was normal. This would appear to indicate reversible ischaemia in the left posterior region, and is consistent with the reported symptoms. This case illustrates the usefulness of HMPAO in the diagnosis of reversible cerebral ischaemia.

  14. Sacroiliac joint dysfunction: a case study.

    Science.gov (United States)

    Murray, William

    2011-01-01

    Pain is a widespread issue in the United States. Nine of 10 Americans regularly suffer from pain, and nearly every person will experience low back pain at one point in their lives. Undertreated or unrelieved pain costs more than $60 billion a year from decreased productivity, lost income, and medical expenses. The ability to diagnose and provide appropriate medical treatment is imperative. This case study examines a 23-year-old Active Duty woman who is preparing to be involuntarily released from military duty for an easily correctable medical condition. She has complained of chronic low back pain that radiates into her hip and down her leg since experiencing a work-related injury. She has been seen by numerous providers for the previous 11 months before being referred to the chronic pain clinic. Upon the first appointment to the chronic pain clinic, she has been diagnosed with sacroiliac joint dysfunction. This case study will demonstrate the importance of a quality lower back pain assessment.

  15. Delivering Online Examinations: A Case Study

    Directory of Open Access Journals (Sweden)

    John MESSING

    2004-07-01

    Full Text Available Delivering Online Examinations: A Case Study Jason HOWARTH John MESSING Irfan ALTAS Charles Sturt University Wagga Wagga-AUSTRALIA ABSTRACT This paper represents a brief case study of delivering online examinations to a worldwide audience. These examinations are delivered in partnership with a commercial online testing company as part of the Industry Master’s degree at Charles Sturt University (CSU. The Industry Master’s degree is an academic program for students currently employed in the IT industry. Using Internet Based Testing (IBT, these students are examined in test centres throughout the world. This offers many benefits. For example, students have the freedom of sitting exams at any time during a designated interval. Computer-based testing also provides instructors with valuable feedback through test statistics and student comments. In this paper, we document CSU’s use of the IBT system, including how tests are built and delivered, and how both human and statistical feedback is used to evaluate and enhance the testing process.

  16. Organisational culture and learning: a case study.

    Science.gov (United States)

    Bell, Elaine

    2013-11-01

    To explore the impact organisational cultures have on the learning experience of student nurses and identify the influencing factors. A case study approach was used. The single case being a Defence School of Health Care Studies (DSHCS) and the multiple units of analysis: student nurses, the lecturers and Student Standing Orders. An in depth three dimensional picture was achieved using multiple data collection methods: interview, survey, observation and document analysis. The findings suggest that the DSHCS is perceived to be a sub-culture within a dominant civilian learning culture. Generally, the students and staff believed that the DSHCS is an excellent learning environment and that the defence students overall are high achievers. The common themes that appeared from the data were image, ethos, environment, discipline, support, welfare and a civilian versus military way of thinking. The learning experience of defence student nurses is very positive and enhanced by the positive learning culture of the civilian Higher Educational Institution. The factors influencing a positive learning experience that can be impacted by the overarching culture are discipline, image, ethos of adult learning, support and welfare. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. A postural 'stressed' cerebral HMPAO case study

    International Nuclear Information System (INIS)

    Williams, R.C.; Jost, G.M.; Bolitho, L.; Grantham, M.

    1998-01-01

    Full text: This case study represents an example of the utility of postural hypoperfusion stressed HMPAO SPECT. An elderly woman of 78 with a long history of giddiness was referred to our laboratory for examination of possible cerebral ischaemia. She had recurrent dizzy episodes, sometimes posture related, over the past few years and had suffered several falls. Cerebral DSA revealed minimal disease. CT scans were reported as normal. Carotid duplex Doppler studies revealed bilateral plaque disease in the carotid bulbs extending to the origins of the ICAs which were not significant stenoses. Postural symptoms were induced by standing the patient up rapidly and HMPAO was administered at the same time. A SPECT scan of the brain was performed. Quantitative analysis showed a left to right decrease of 10.8% in the temporo-occipital area, 5.6% in the temporo-parietal area and 2.5% in the cerebellar and parietal areas. Images revealed moderately reduced tracer concentration in the left half of the cerebellum and the left occipital region extending as far forward as the temporo-parietal region A repeat HMPAO SPECT scan without stress was normal. This would appear to indicate reversible ischaemia in the left posterior region, and is consistent with the reported symptoms. This case illustrates the usefulness of HMPAO in the diagnosis of reversible cerebral ischaemia

  18. Scheduling job shop - A case study

    Science.gov (United States)

    Abas, M.; Abbas, A.; Khan, W. A.

    2016-08-01

    The scheduling in job shop is important for efficient utilization of machines in the manufacturing industry. There are number of algorithms available for scheduling of jobs which depend on machines tools, indirect consumables and jobs which are to be processed. In this paper a case study is presented for scheduling of jobs when parts are treated on available machines. Through time and motion study setup time and operation time are measured as total processing time for variety of products having different manufacturing processes. Based on due dates different level of priority are assigned to the jobs and the jobs are scheduled on the basis of priority. In view of the measured processing time, the times for processing of some new jobs are estimated and for efficient utilization of the machines available an algorithm is proposed and validated.

  19. Location of existing Case Studies on Open Education

    OpenAIRE

    Burke, Siobhan

    2014-01-01

    Members of the Open Education Special Interest Group have collected a selection of short case studies on Open Education. View all of the case studies at http://repository.alt.ac.uk/view/divisions/CaseStudies/ Location of existing Case Studies on Open Education: The following lists aims to capture and amalgamate the various different case study sources which have been created and developed within the UK around experiences of Open Educational Resources.

  20. Subgap Two-Photon States in Polycyclic Aromatic Hydrocarbons: Evidence for Strong Electron Correlations

    OpenAIRE

    Aryanpour, K.; Roberts, A.; Sandhu, A.; Rathore, R.; Shukla, A.; Mazumdar, S.

    2013-01-01

    Strong electron correlation effects in the photophysics of quasi-one-dimensional $\\pi$-conjugated organic systems such as polyenes, polyacetylenes, polydiacetylenes, etc., have been extensively studied. Far less is known on correlation effects in two-dimensional $\\pi$-conjugated systems. Here we present theoretical and experimental evidence for moderate repulsive electron-electron interactions in a number of finite polycyclic aromatic hydrocarbon molecules with $D_{6h}$ symmetry. We show that...

  1. Water-Sediment Partition of Polycyclic Aromatic Hydrocarbons (PAHs) in Nansi Lake

    Science.gov (United States)

    Zhang, Guizhai; Diao, Youjiang

    2018-06-01

    Based on field data of polycyclic aromatic hydrocarbons (PAHs) in water and sediment in Nansi Lake. The concentrations and the partitioning characteristic of PAHs in the water and sediment were studied. The lgKd of high molecular weight PAHs were higher than the low molecular weight PAHs. The most of PAHs Kd values were negligible correlated with TOC, soluble salt, clay and pH of the sediment in Nansi Lake.

  2. Urinary 1-Hydroxypyrene as a Biomarker to Carcinogenic Polycyclic Aromatic Hydrocarbon Exposure

    OpenAIRE

    Clinton Ifegwu; Kayode Osunjaye; Folasade Fashogbon; Kolawole Oke; Afolabi Adeniyi; Chimezie Anyakora

    2012-01-01

    In order to capture the extent of exposure to polycyclic aromatic hydrocarbons (PAHs), various biomarkers have been employed. The biomarkers employed for PAHs include PAHs genetoxic end points in lymphocytes, urinary metabolites, PAH-DNA adducts, and PAH-Protein adducts. Of these, excretory 1-hydroxypyene, a metabolite of pyrene, has been used extensively as a biological monitoring indicator of exposure to PAHs. This study attempts to assess the level of this biomarker in the body fluid of 68...

  3. The Effect of Using Case Studies in Business Statistics

    Science.gov (United States)

    Pariseau, Susan E.; Kezim, Boualem

    2007-01-01

    The authors evaluated the effect on learning of using case studies in business statistics courses. The authors divided students into 3 groups: a control group, a group that completed 1 case study, and a group that completed 3 case studies. Results evidenced that, on average, students whom the authors required to complete a case analysis received…

  4. On misunderstandings in connection with case-studies

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    2005-01-01

    This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...

  5. Stakeholders and Apart Hotels: Multiple Case Study

    Directory of Open Access Journals (Sweden)

    Elizabeth Kyoko Wada

    2012-09-01

    Full Text Available Means of accommodation involve a wide range of social actors and agents, as well as different business models. Management strategies in this sector have been increasingly important for long-term sustainability and competitiveness of business organizations. This study aims to analyze the interactions between apart-hotels and their stakeholders to foster an improvement of services provided, aligning the interface of strategic management from the point of view of managers and their key stakeholders. It is an exploratory study, with qualitative chacter, along with multiple case studies of the following establishments: Travel Inn, Hotels Slaviero and Etoile george v. Brazilian enterprises, which manage lodging facilities with apart-hotel concepts, combining features that enable comparative analysis of the study. For conceptual understanding, this study was based on literature about stakeholders, taking the work of Freeman (1984 and Freeman et al (2010 as main references. The research was conducted through semi-structured interviews with managers of lodging facilities and their key stakeholders and through direct observation and documentation. We found that not all groups of influence are considered in the planning of service flats. However, the organizations surveyed indicated that the market has realized the importance of the groups that exert influence and are influenced by their goals, and are therefore increasingly alert for integration of such groups in their strategic planning.

  6. Embodiment of the Spirit: A Case Study

    Directory of Open Access Journals (Sweden)

    Jan Grimell

    2017-02-01

    Full Text Available Adopting a longitudinal approach to exploring the psychology of the transition from military to civilian life, one case study is presented that adds a spiritual perspective to the transition process. This case study serves as an example representative from a group of participants who have been followed through a research project on identity reconstruction during the transition to civilian life. This individual, not unlike many others within the group, undergoes an unexpected progression of the military I-position of the self throughout the process of becoming a civilian. This study utilizes a dialogical approach to the identity work to further the understanding of longitudinal adjustments to the self. An analysis of the narrative developments and interactions among pre-existing and new I-positions of the self over time has been made based upon three annually conducted interviews spanning from 2014 to 2016. The results lead to the suggestion that if a military I-position of the self grows more salient and voiced throughout the process of transitioning into civilian life, then this vocalization may be related to the spirit of a person embodied in a specific I-position of the self. Such growth of a military I-position after leaving active service may gravitate around a deep sense of “who I am” with a profound sense of meaning attached to this position. Instead of perceiving as an unwanted development the growth of a military sense of “who I am,” one should acknowledge it as a deeper dimension of self and life. It is important to find an outlet for such a progression of the self so as to sustain balance and dialogue. Future research is encouraged to further examine these qualitative findings.

  7. Quality improvement initiatives in a case management service: case study.

    Science.gov (United States)

    Davies, Deborah J

    2015-01-01

    This article explores the importance of quality practices in underpinning the person-centred approach at a Community Options Program (COP) case management service in northern NSW. The NSW community care sector does not have a statutory excellence body to identify, promote and support improved practices and quality and safety across community services, and therefore the COP provider decided to establish a dedicated role to focus on the quality improvement of its service. The subsequent quality improvement initiatives have included mapping the clients' journey through the service, identifying areas to standardise practice, and creating service pathways. The clients' journey was used as the framework to identify where standardised practice was required, and a robust process was implemented to develop over 25 good practice guidelines and tools that addressed the variations in practice and enabled the service pathways to be developed. Prior to trialling the guidelines and tools, staff received education sessions on the anticipated changes to practice, and the practicality and applicability of the guidelines were evaluated at the end of the trials. This information was reviewed and the guidelines were amended accordingly before being rolled out. The guidelines have been in use for over 12 months and have provided the benchmark against which to audit practice, and have resulted in key performance improvements such as an increase in client review rates and a rise in the feedback response rate from clients, with a noticeable shift in the comments about the brokered support worker to acknowledging the role of their case manager. Formalising informal supports for those clients that lived alone also increased, which means these people are less reliant on services and there is a reduced risk of social isolation.

  8. Logistics opportunity costs: A mining case study

    Directory of Open Access Journals (Sweden)

    Leani van Jaarsveld

    2013-11-01

    Full Text Available This study highlighted the importance of determining the impact that an ineffective mode of transport has on a firm’s transportation model and costs. The main focus of this study was to determine the logistics opportunity costs of using road transport within a mining firm. A case study approach was followed, as the investigation aimed to analyse a complex problem experienced by one company and present it in an easily understandable format. From the results of this study, it was apparent that the logistics opportunity costs associated with the mode of transport was substantial. This highlighted the need for firms to revise their choice of transport mode on a regular basis, as it has a major impact not only on their transportation costs, but also on their inventory holding and carbon emissions. The results also have implications for South Africa’s only freight railway, Transnet Freight Rail, which should not only focus on expanding its existing capacity, but also on improving its customer service delivery whilst containing tariff increases.

  9. Subungual squamous cell carcinoma: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Neill, Cory J., E-mail: coryjneill@gmail.com

    2017-07-01

    The purpose of this case study is to describe a dosimetric delivery of radiation to a superficial disease process involving the skin and bone of the distal finger. A 76-year-old male patient presented with a subungual squamous cell carcinoma (SCC) of the left distal index finger with bony involvement. The patient refused conventional surgical treatment but agreed to external beam radiation therapy (EBRT). There is a gap in the current literature describing how to successfully immobilize fingers and which EBRT modality is dosimetrically advantageous in treating them. The construction of a simple immobilization method with the patient in a reproducible position is described. The use of photons and electrons were compared ultimately showing photons to be dosimetrically advantageous. Long-term efficacy of the treatment was not evaluated because of patient noncompliance.

  10. Case studies of attacks on communication networks

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sin Bok; Han, Eon Suk [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-06-15

    Recently, as the computer hardware and communications are developed, the data exchange through inter-networking has been highlighted and the data is being recognized as a great asset. Most of the organizations, businesses and enterprises are open to the external world-computer communication networks, attention must be focused on the securities of the information infrastructure. A government organization has been developing 'Circuits Analyzers', and 'Hacker-Tracking Program' and is struggling to track down sneakers. In this report, we analyze the contents of the cases where the communication network has been invaded, from the past up until now in Korea. This report also contains the result of a study on E-mail security, for the protection of KAERI Integrated Management Information System under which utilizes the CALS concepts and web services. (Author)

  11. Understanding Support - lessons from a case study

    Directory of Open Access Journals (Sweden)

    Chris Sauer

    1993-11-01

    Full Text Available Support from top management and others is agreed to be an important factor in information systems success and failure, but little is written about how it has its effect and how it might be managed to a project's advantage. A recently developed conceptual framework is described. It covers the nature and forms of support, the way support affects project outcomes, the bases on which support is provided, and the strategies by which support may be managed. The framework is used to analyse a case study in several stages. At the end of the analysis of each stage, the framework's utility is assessed in terms of its explanatory value and the practical advice it suggests. Areas for further research are identified.

  12. Environmental Comparative Risk Assessment: A Case Study

    International Nuclear Information System (INIS)

    Ali, M.M.

    2007-01-01

    Health and environmental impacts associated with energy production and industrial activities as well as food production and agricultural activities have had great concern in the last decades. Early activities emerged in late 80s of the last century through an Inter- Agency project (lAEA, UNDY, WHO, ... ) on the comparative risk assessment from energy systems and industrial complexes. A work-shop on Risk Assessment and Management in large industrial areas was held in Alexandria Egypt on 20-33 Det 1993, sponsored by IAEA. Several conferences, experts work groups and workshops were held there of Recent trends in determining risks are: 1. Use of probabilistic risk assessment approach to identify hazardous activities and accident scenario. 2. development of data base on failure probabilities and appropriate physical models. 3. Development of related directives and regulations and criteria Comparative risk assessment case study as a tool for comparing risk is emphasized Criteria of exposure to human and ecological risks are addressed

  13. Case studies of attacks on communication networks

    International Nuclear Information System (INIS)

    Kang, Sin Bok; Han, Eon Suk

    1996-06-01

    Recently, as the computer hardware and communications are developed, the data exchange through inter-networking has been highlighted and the data is being recognized as a great asset. Most of the organizations, businesses and enterprises are open to the external world-computer communication networks, attention must be focused on the securities of the information infrastructure. A government organization has been developing 'Circuits Analyzers', and 'Hacker-Tracking Program' and is struggling to track down sneakers. In this report, we analyze the contents of the cases where the communication network has been invaded, from the past up until now in Korea. This report also contains the result of a study on E-mail security, for the protection of KAERI Integrated Management Information System under which utilizes the CALS concepts and web services. (Author)

  14. Anxiety or neurosis: case report study

    Directory of Open Access Journals (Sweden)

    Miloš Židanik

    2005-11-01

    Full Text Available Background: With the publication of the Diagnostic and Statistical Manual, Third Edition (DSM-III in 1980, anxiety disorder was first identified as a diagnostic entity. A new theoretical approach regarding aetiology of anxiety disorders came next into the view, far from Freud’s psychoanalytical pathways. The consequences were new therapeutic guidelines, including psychopharmacotherapy and the use of behavioural and cognitive psychotherapy.Methods: The paper presents a case report study of a patient with social phobia. The use of analytical oriented psychotherapy, which helped to resolve Axis I symptoms, is described.Conclusions: In spite of new therapeutic guidelines there is still a certain population of patients with the need for psychoanalytical oriented psychotherapy. If we are to surrender the Freud’s legacy to the medical history, we will weaken psychiatry as a science and will narrow our therapeutic field.

  15. A case study of strategic planning IFB

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Rodrigues de Camargo Dias

    2018-03-01

    Full Text Available The purpose of this article is to identify and characterize the initial stage of the IFB strategic planning, based on the perception of top management and planning team. The case study adopts a qualitative approach supported by bibliographic research techniques, to build a theoretical foundation, allied to the semistructure interview for later, application of the content analysis. As a result, we can identify that the institution opted to first define the strategic references, based on the construction of the mission, vision and values, and later, analysis of the organizational diagnosis, based on the Balanced Scorecard methodology. It was verified that the tool of strategic planning and its use are points that need to be better understood by the managers and technical planning team. The predominant characteristics of strategic planning are composed of a programmatic tool for projecting medium and long term goals and actions, of legal compliance, as it integrates and operationalizes the Institutional Development Plan (PDI.

  16. LM2500+ Brush Seal Case Study

    Science.gov (United States)

    Haaser, Fred G.

    2006-01-01

    The LM2500+ industrial aeroderivative gas turbine, a 25% enhanced power derivative of the LM2500 gas turbine, recently completed its development test program during the period 5/96 - 10/96. Early in the engine program a Quality Function Deployment (QFD) process was used to determine customer needs for this project.The feedback obtained from the QFD process showed without doubt that gas turbine customers now emphasize product reliability and availability at the top of their needs. One area of development on the LM2500+ was to investigate the use of a brush seal as a means to reduce undesirable turbine cooling leakages within the turbine mid frame in order to enhance part life. This presentation presents a case study on the factors that went into evaluating a brush seal during engine test, test results, and the ultimate decision not to implement the brush seal for cost and other reasons.

  17. Tailoring Colors by O Annulation of Polycyclic Aromatic Hydrocarbons.

    Science.gov (United States)

    Miletić, Tanja; Fermi, Andrea; Orfanos, Ioannis; Avramopoulos, Aggelos; De Leo, Federica; Demitri, Nicola; Bergamini, Giacomo; Ceroni, Paola; Papadopoulos, Manthos G; Couris, Stelios; Bonifazi, Davide

    2017-02-16

    The synthesis of O-doped polyaromatic hydro- carbons in which two polycyclic aromatic hydrocarbon sub units are bridged through one or two O atoms has been achieved. This includes high-yield ring-closure key steps that, depending on the reaction conditions, result in the formation of furanyl or pyranopyranyl linkages through intramolecular C-O bond formation. Comprehensive photophysical measurements in solution showed that these compounds have exceptionally high emission yields and tunable absorption properties throughout the UV/Vis spectral region. Electrochemical investigations showed that in all cases O annulation increases the electron-donor capabilities by raising the HOMO energy level, whereas the LUMO energy level is less affected. Moreover, third-order nonlinear optical (NLO) measurements on solutions or thin films containing the dyes showed very good values of the second hyperpolarizability. Importantly, poly(methyl methacrylate) films containing the pyranopyranyl derivatives exhibited weak linear absorption and NLO absorption compared to the nonlinearity and NLO refraction, respectively, and thus revealed them to be exceptional organic materials for photonic devices. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  18. A case study in pathway knowledgebase verification

    Directory of Open Access Journals (Sweden)

    Shah Nigam H

    2006-04-01

    Full Text Available Abstract Background Biological databases and pathway knowledgebases are proliferating rapidly. We are developing software tools for computer-aided hypothesis design and evaluation, and we would like our tools to take advantage of the information stored in these repositories. But before we can reliably use a pathway knowledgebase as a data source, we need to proofread it to ensure that it can fully support computer-aided information integration and inference. Results We design a series of logical tests to detect potential problems we might encounter using a particular knowledgebase, the Reactome database, with a particular computer-aided hypothesis evaluation tool, HyBrow. We develop an explicit formal language from the language implicit in the Reactome data format and specify a logic to evaluate models expressed using this language. We use the formalism of finite model theory in this work. We then use this logic to formulate tests for desirable properties (such as completeness, consistency, and well-formedness for pathways stored in Reactome. We apply these tests to the publicly available Reactome releases (releases 10 through 14 and compare the results, which highlight Reactome's steady improvement in terms of decreasing inconsistencies. We also investigate and discuss Reactome's potential for supporting computer-aided inference tools. Conclusion The case study described in this work demonstrates that it is possible to use our model theory based approach to identify problems one might encounter using a knowledgebase to support hypothesis evaluation tools. The methodology we use is general and is in no way restricted to the specific knowledgebase employed in this case study. Future application of this methodology will enable us to compare pathway resources with respect to the generic properties such resources will need to possess if they are to support automated reasoning.

  19. A case study in pathway knowledgebase verification.

    Science.gov (United States)

    Racunas, Stephen A; Shah, Nigam H; Fedoroff, Nina V

    2006-04-08

    Biological databases and pathway knowledge-bases are proliferating rapidly. We are developing software tools for computer-aided hypothesis design and evaluation, and we would like our tools to take advantage of the information stored in these repositories. But before we can reliably use a pathway knowledge-base as a data source, we need to proofread it to ensure that it can fully support computer-aided information integration and inference. We design a series of logical tests to detect potential problems we might encounter using a particular knowledge-base, the Reactome database, with a particular computer-aided hypothesis evaluation tool, HyBrow. We develop an explicit formal language from the language implicit in the Reactome data format and specify a logic to evaluate models expressed using this language. We use the formalism of finite model theory in this work. We then use this logic to formulate tests for desirable properties (such as completeness, consistency, and well-formedness) for pathways stored in Reactome. We apply these tests to the publicly available Reactome releases (releases 10 through 14) and compare the results, which highlight Reactome's steady improvement in terms of decreasing inconsistencies. We also investigate and discuss Reactome's potential for supporting computer-aided inference tools. The case study described in this work demonstrates that it is possible to use our model theory based approach to identify problems one might encounter using a knowledge-base to support hypothesis evaluation tools. The methodology we use is general and is in no way restricted to the specific knowledge-base employed in this case study. Future application of this methodology will enable us to compare pathway resources with respect to the generic properties such resources will need to possess if they are to support automated reasoning.

  20. Laryngeal sarcoidosis: a case-control study.

    Science.gov (United States)

    Duchemann, Boris; Lavolé, Armelle; Naccache, Jean-Marc; Nunes, Hilario; Benzakin, Sylvain; Lefevre, Marine; Kambouchner, Marianne; Périé, Sophie; Valeyre, Dominique; Cadranel, Jacques

    2014-10-20

    We undertook a study on a series of laryngeal sarcoidosis (LS), a very rare and often threatening localization to better specify laryngeal manifestations, sarcoidosis clinical expression and long-term follow-up. This was a retrospective case-control study. All LS patients from two French centers were included and compared to sarcoidosis patients without laryngeal localization with two controls for one patient. Twelve consecutive LS patients were recruited between 1993 and 2011. LS revealed sarcoidosis in eight cases (67%). The most common symptoms were hoarseness (77%), inspiratory dyspnea (38%) and dysphagia (38%). Epidemiological characterisics were not different. Extrapulmonary localizations were significantly more common in LS patients than in controls (92% vs. 54%, p=0.02), particularly lupus pernio (25% vs. 0%, p=0.03) and nasosinusal involvement (83% vs. 4%, p<0.01) while thoracic involvement was less frequent (58% vs 100%, p < 0.01). Treatment rates were higher in the LS group (92% vs. 58%, p=0.04), and treatment duration was longer (median: 81 vs. 13 months, p=0.04), with frequent long-term treatment (67%, N=8/12). Two patients underwent surgery. One patient needed temporary tracheostomy during the course of the disease; Remission rates were lower in LS patients (9% vs. 58% at 2 years p<0.01). Eventually, there was no death nor definitive tracheotomy. LS is a rare condition that is often associated to other loco-regional localizations. LS are often difficult to manage. Survival is good but may require a medico-surgical approach.

  1. Soil sealing degree as factor influencing urban soil contamination with polycyclic aromatic hydrocarbons (PAHs

    Directory of Open Access Journals (Sweden)

    Mendyk Łukasz

    2016-03-01

    Full Text Available The objective of the study was to determine role of soil sealing degree as the factor influencing soil contamination with polycyclic aromatic hydrocarbons (PAHs. The study area included four sampling sites located within the administrative boundaries of the Toruń city, Poland. Sampling procedure involved preparing soil pits representing three examples of soil sealing at each site: non-sealed soil as a control one (I and two degrees of soil sealing: semi-pervious surface (II and totally impervious surface (III. Together with basic properties defined with standard procedures (particle size distribution, pH, LOI, content of carbonates content of selected PAHs was determined by dichloromethane extraction using gas chromatography with mass spectrometric detection (GC-MS. Obtained results show that urban soils in the city of Toruń are contaminated with polycyclic aromatic hydrocarbons. Soil sealing degree has a strong influence on the soil contamination with polycyclic aromatic hydrocarbons. Totally sealed soils are better preserved from atmospheric pollution including PAHs. Combustion of grass/wood/coal was the main source of determined PAHs content in examined soils.

  2. Integrative health coaching: an organizational case study.

    Science.gov (United States)

    Wolever, Ruth Q; Caldwell, Karen L; Wakefield, Jessica P; Little, Kerry J; Gresko, Jeanne; Shaw, Andrea; Duda, Linda V; Kosey, Julie M; Gaudet, Tracy

    2011-01-01

    The aim of this study was to describe integrative health (IH) coaching as developed in three different interventions offered through a major medical center, as a step toward further defining the field of health coaching. An organizational case study was conducted with document analysis and interviews. Interviewees were the first six IH coaches at Duke Integrative Medicine who provided 360 clients with individual and/or group coaching (two to 28 sessions) in a randomized clinical study and two work-site wellness programs. Qualitative analysis using the constant comparative method was conducted. Integrative health coaching is characterized by a process of self-discovery that informs goal setting and builds internal motivation by linking clients' goals to their values and sense of purpose. Time, commitment, and motivation are necessary in the IH coaching process. The underpinnings of IH coaching are distinct from the medical model, and the process is distinct from health education, executive coaching, and psychotherapy. Integrative health coaching fits well with the assumptions of integrative medicine and has a role in supporting behavior change. Copyright © 2011. Published by Elsevier Inc.

  3. [Study of 103 cases of odontogenic cysts].

    Science.gov (United States)

    Moctezuma-Bravo, Gustavo Sergio; Magallanes-González, Eduardo

    2009-01-01

    To describe characteristics of odontogenic cysts in a Mexican population. A retrospective study of 103 odontogenic cysts in 86 patients was done. The data were obtained from files of the Pathology Department of a General Hospital. We observed a frequency of the 8.13 % of odontogenic cysts (103) in 1266 pathological studies. The dentigerous cyst 56 % and odontogenic keratocyst 33 % were the most common odontogenic cysts. Sixty one percent of the cysts appeared in the second and third decades of life. In 71 cysts, 42 % appeared in the posterior region jaw, 29 % in the anterior region of the maxilla and 21 % in the posterior region of the maxilla. A 6.7 % developed a recurrence after treatment and a case of keratocyst of posterior region of the maxilla was associated with epidermoid carcinoma. The study included three women with the syndrome of carcinoma of the basal cell nevus, who presented multiple keratocysts. The dentigerous cysts and odontogenic keratocysts were the most frequent odontogenic cysts. They appeared mainly in the second and third decades of life.

  4. Occupational risk factors for renal cell carcinoma: agent-specific results from a case-control study in Germany. MURC Study Group. Multicenter urothelial and renal cancer study.

    Science.gov (United States)

    Pesch, B; Haerting, J; Ranft, U; Klimpel, A; Oelschlägel, B; Schill, W

    2000-12-01

    This case-control study was conducted to estimate the renal cell cancer (RCC) risk for exposure to occupation-related agents, besides other suspected risk factors. In a population-based multicentre study, 935 incident RCC cases and 4298 controls matched for region, sex, and age were interviewed between 1991 and 1995 for their occupational history and lifestyle habits. Agent-specific exposure was expert-rated with two job-exposure matrices and a job task-exposure matrix. Conditional logistic regression was used to calculate smoking adjusted odds ratios (OR). Very long exposures in the chemical, rubber, and printing industries were associated with risk for RCC. Males considered as 'substantially exposed to organic solvents' showed a significant excess risk (OR = 1.6, 95% CI : 1.1-2.3). In females substantial exposure to solvents was also a significant risk factor (OR = 2.1, 95% CI : 1.0-4.4). Excess risks were shown for high exposure to cadmium (OR = 1.4, 95% CI : 1.1-1.8, in men, OR = 2.5, 95% CI : 1.2-5.3 in women), for substantial exposure to lead (OR = 1.5, 95% CI : 1.0-2.3, in men, OR = 2.6, 95% CI : 1.2-5.5, in women) and to solder fumes (OR = 1.5, 95% CI : 1.0-2.4, in men). In females, an excess risk for the task 'soldering, welding, milling' was found (OR = 3.0, 95% CI : 1.1-7.8). Exposure to paints, mineral oils, cutting fluids, benzene, polycyclic aromatic hydrocarbons, and asbestos showed an association with RCC development. Our results indicate that substantial exposure to metals and solvents may be nephrocarcinogenic. There is evidence for a gender-specific susceptibility of the kidneys.

  5. Landslide Economics: Concepts and Case Studies

    Science.gov (United States)

    Klose, Martin; Damm, Bodo

    2015-04-01

    Landslide economics is vital for fundamental understanding of landslide risk as dealing with two important topics: (i) impact assessment, either as damage statistics or cost modeling, and (ii) vulnerability assessment, i.e., the study of exposure, sensitivity, and resilience to landslide damage, ideally from both sociotechnical and financial perspective (e.g., Crovelli and Coe, 2009; Wills et al., 2014). Many aspects addressed in landslide economics have direct influence on landslide risk, including: (i) human activity is often a major causative factor of landslides, not only by predisposing or triggering them, but also as a result of inadequate (low-cost) landslide mitigation; (ii) the level of tolerable or acceptable risk, a measure driving a large part of landslide costs in industrialized countries, is highly variable, differing between individuals, public or private organizations, and societies, with its nature being to change over time; and (iii) decision makers are faced with finding the right balance in landslide mitigation, thus need to weight diverse geological and socioeconomic factors that control its effectiveness in both technical and financial terms (e.g., Klose et al., 2014a). A large part of the complexity in assessing landslide risk as measured by economic costs is due to unique problems in understanding of (i) what types of landslide damage affect human activity and infrastructure in which way, (ii) how society contributes and responds to various kinds of damage, and (iii) how landslide damage is valued in monetary terms. Landslide economics shows the potential to take account of these sociocultural factors to the benefit of risk analysis (e.g., Klose et al., 2014b). The present contribution introduces local and regional case studies in which different economic issues of landslide risk are highlighted using the example of public infrastructures in NW Germany. A special focus is on the following topics: (i) risk culture and created risk, (ii

  6. Evaluation of Simple Treat 3.0 for two hydrophobic and slowly biodegradable chemicals: Polycyclic musks HHCB and AHTN

    NARCIS (Netherlands)

    Artola-Garicano, E.; Hermens, J.L.M.; Vaes, W.H.J.

    2003-01-01

    In the current study, predictions by Simple Treat 3.0, a fate model for organic chemicals in sewage treatment plants (STPs), are compared with actual measurements in three STPs. Two polycyclic musks, Tonalide® (AHTN) and Galaxolide® (HHCB), were used for model evaluation. Results show that Simple

  7. Analysis of polycyclic aromatic hydrocarbons I. Determination by gas chromatography with glass and fused silica capillary columns

    International Nuclear Information System (INIS)

    Perez, M. M.; Gonzalez, D.

    1987-01-01

    A study of the analysis by gas chromatography of aromatic polycyclic hydrocarbons is presented. The separation has been carried out by glass and fused silica capillary column. The limitations and the advantages of the procedure are discussed in terms of separation efficiency, sensitivity and precision. (Author) 17 refs

  8. Analysis of polycyclic aromatic hydrocarbons. I. Determination by gas chromatography with glass and fused solica capillary columns

    International Nuclear Information System (INIS)

    Perez Garcia, M.; Gonzalez, D.

    1987-01-01

    A study of the analysis by gas chromatography of aromatic polycyclic hydrocarbons is presented. The separation has been carried out by glass and fused silice capillary column. The limitations and the advantages of the procedure are discussed in terms of separation efficiency, sensitivity and precision. (author). 3 figs., 17 refs

  9. Content of heterocyclic amines and polycyclic aromatic hydrocarbons in pork, beef and chicken barbecued at home by Danish consumers

    DEFF Research Database (Denmark)

    Aaslyng, Margit D.; Duedahl-Olesen, Lene; Jensen, Kirsten

    2013-01-01

    It is a well-known fact that, when meat is barbecued, several harmful components, including heterocyclic amines (HCA) and polycyclic aromatic hydrocarbons (PAH), may be formed. The aim of this study was to determine the HCA and PAH content in meat (pork, chicken and beef) when barbecued at home...

  10. IMPACTS OF AGING ON IN VIVO AND IN VITRO MEASUREMENTS OF SOIL-BOUND POLYCYCLIC AROMATIC HYDROCARBON AVAILABILITY

    Science.gov (United States)

    Ingestion of contaminated soil is an exposure pathway at approximately one-half of the Superfund sites in the United States. This study was designed to evaluate the impacts of aging in soil on the availability of polycyclic aromatic hydrocarbons (PAHs). Two coal tar (CT)-amended ...

  11. The occupational exposure of dermatology nurses to polycyclic aromatic hydrocarbons - evaluating the effectiveness of better skin protection.

    NARCIS (Netherlands)

    Scheepers, P.T.J.; Houtum, J.L.M. van; Anzion, R.B.M.; Champmartin, C.; Hertsenberg, S.; Bos, R.P.; Valk, P. van der

    2009-01-01

    OBJECTIVES: We studied the uptake of polycyclic aromatic hydrocarbons (PAH) in nurses who apply ointments containing coal tar to patients and investigated the effectiveness of skin protection methods. METHODS: We determined gas-phase PAH on XAD-2 and particle-associated PAH on filters. We also used

  12. Data Rescue Case Studies from the Cryosphere

    Science.gov (United States)

    Fetterer, F. M.

    2017-12-01

    A simple definition of the cryosphere is "where the world is frozen", or where water takes the form of snow and ice. The cryosphere is shrinking as the Earth warms. Data, particularly old data, document this in often eye-opening fashion. A photograph of Alaska's Muir Glacier taken in 1902 next to one taken in 2005 has impact that a line graph of air temperature anomalies from a weather station can't match, even though temperature data are fundamental to climate research and to understanding the glacier retreat captured in the photographs. Whaling logbooks from the late 1800s, maps of sea ice shared internationally in the 1930s, and satellite images of the polar oceans from the 1960s are not as immediately thought-provoking as are glacier photographs, but when preserved and documented they provide a record of sea ice coverage that is more than 100 years long. We developed a data product from these and other sources that is used in meteorological reanalysis and to answer questions about ice in the Arctic prior to 1978, when commonly used satellite-data-derived sea ice records begin. Preserving glacier photographs and making them available online, and publishing a gridded sea ice data product that builds on the preservation work of others are examples of data rescue projects that benefit scientific research and mobilize knowledge. These and other case studies suggest that even absent secure funding and an organizational setting that supports data rescue, important data make the transition from someone's office to archived and online with metadata because scientists are impassioned about the data they collect and want others to be able to use these data. In these cases from the cryosphere, student interns, collaborations with librarians, and cooperation with colleagues in other data centers have made it possible to preserve data at low cost.

  13. Case studies on age-management in organisations: report on organisational case studies

    NARCIS (Netherlands)

    Punte, E.; Conen, W.S.; Schippers, J.; Henkens, C.J.I.M.

    2011-01-01

    The acquisition of case studies was thwarted by the economic crisis and the feeling of being ‘over-researched’ by potential organisations. Although organisations in some sectors (e.g. chemical manufacturing) reported the worst part of the economic crisis was behind, many organisations indicated

  14. Case Study: The Mystery of the Seven Deaths--A Case Study in Cellular Respiration

    Science.gov (United States)

    Gazdik, Michaela

    2014-01-01

    Cellular respiration, the central component of cellular metabolism, can be a difficult concept for many students to fully understand. In this interrupted, problem-based case study, students explore the purpose of cellular respiration as they play the role of medical examiner, analyzing autopsy evidence to determine the mysterious cause of death…

  15. BOOK REVIEW: Case Studies in Knowledge Management

    Directory of Open Access Journals (Sweden)

    Reviewed by Dr. Adnan BOYACI

    2005-10-01

    Full Text Available 161Case Studies in Knowledge ManagementEdited by Murray JennexHersley: PA: Idea Group, 2005, pp. 372, ISBN 1-59140-352-9Reviewed by Dr. Adnan BOYACIAnadolu UniversityEskişehir-TurkeyKnowledge management (KM as a structured system and the way to the effectiveness isrelatively new field for the contemporary organizations functioning in different andcompetitive domain of public and private sectors in terms of getting optimal effectivenessunderlined by the concepts such as quality, productivity…etc. Because of the growingimportance and the popularity of the KM either as a research topic or specialized coursesubject, a crucial need for understanding, conceptualization and implementation of KM asa system has emerged since the mid 1990’s. In this sense, the book contributes criticallyto fill the gap between theory and implementation as a teaching material.This edited book is published by Idea Group Publishing. The book has twenty chaptersdivided into seven sections. In addition to a section of authors’ biography contributing thebook and an index, there is a preface that the basic terms and key concepts underliningthe cases discussed following chapters, which is explained in a schematized way.Besides the editor, total of 47 authors have contributed to the book. These authors arefrom different countries, academic backgrounds, and institutions. Although approximatelyone third of the authors are from USA, the rest of the authors are from Canada, England,Austria, Germany, Australia, New Zealand, Egypt, Bahrain and China. The authorsrepresent a variety of universities, private companies, and military institutions. Most ofthem have strong professional backgrounds, which help them address the issues bothfrom theoretical and practical perspectives. Contributions of authors having differentbackgrounds and institutions enable the book to have very comprehensive spectrum andthis makes the book attractive practically for those working different sectors

  16. Case studies of selected Project "Flash" events

    Directory of Open Access Journals (Sweden)

    K. A. Nicolaides

    2009-03-01

    Full Text Available Flooding is a consequence of the prevailing meteorological situation, the intensity and duration of precipitation, geomorphology, human activities over a geographical region and other factors. Floods result in damage and destruction of infrastructure and private property and, in some cases, in fatalities. Flash floods are sudden and quite localized in extend, characterized by excessive amounts of rainfall within a short period of time and are distinguished from other floods by their degree of severity. The broader knowledge concerning flash floods is useful for the better understanding of the underlying thermodynamic and dynamic mechanisms, as well as the associated physical processes. The wider understanding of flashfloods can form part of an integrated system for short and very short forecasting of these events. In the present study, the synoptic, dynamic and thermodynamic conditions during the development of a baroclinic depression which affected the area of Cyprus on 6 November 2005 are studied. The depression was associated with extreme weather phenomena, such as thunderstorms, a water spout and high precipitation accumulations. The results indicate the importance of the dynamic parameters in the system's development and the thermodynamic analysis has shown the convective potential of the atmosphere.

  17. Odontoma: a retrospective study of 73 cases

    International Nuclear Information System (INIS)

    An, Seo Young; An, Chang Hyeon; Choi, Karp Shik

    2012-01-01

    The purpose of the present study was to retrospectively evaluate the clinical findings and treatment results for impacted permanent teeth associated with odontomas. We retrospectively investigated 73 odontomas in 72 patients who visited Kyungpook National University Dental Hospital from April 2004 through November 2011. The study was performed using medical records, panoramic radiographs, and pathological reports. Data gathered included age, gender, location, chief complaints, effects on dentition, and treatment of odontoma and the impacted tooth associated with odontoma. Most compound odontomas (46.7%) were found in the second decade and complex odontomas were not related to age. Odontomas showed no gender predilection. Fifty-five cases (75.3%) of odontomas were detected on routine dental radiographs. Sixty percent of compound odontomas occurred in the canine area and 57.1% of complex odontomas in the molar areas. Impaction of permanent teeth (61.6%) was the most common complication on the adjacent teeth. Most odontomas (84.9%) were removed surgically and impacted permanent teeth were managed by surgical removal (53.2%), orthodontic treatment (25.5%), or surgical repositioning (6.4%). There was a statistically significant relation between age and preservation of the impacted permanent teeth associated with odontomas (p<0.01). Early detection and treatment of odontomas increase the possibility of preservation of the impacted tooth. Therefore, it would be suggested that periodic panoramic examination during the first and second decade of life might be beneficial for the early detection and better prognosis of odontomas.

  18. (Case Study: Wastewater Pump Station of Khoramabad

    Directory of Open Access Journals (Sweden)

    Masoud Taheriyoun

    2014-10-01

    Full Text Available Evaluation of a Biofilter System for Removal of Hydrogen Sulfide Gas (Case Study: Wastewater Pump Station of Khorramabad Abstract The biofilter system is one of the methods commonly used for the removal of hydrogen sulfide as the main source of odors emitted from wastewater facilities. The system is based on using the contaminant material as bedding to feed microorganisms. To achieve the desirable removal efficiency, it is, therefore, essential to create the proper conditions for the bacteria to grow on the bedding. In this study, a pilot-scale biofilter made of compost and woodchip (with a compost/woodchip ratio of 5:1 was used as the bedding material at Khorrmabad wastewater pumping station to investigate the performance of the system under real conditions. The experiment was carried out over 75 days during which time the input and output H2S concentrations were measured on a regular basis. Moisture was adjusted between 40% and 60% throughout the experiment to provide optimal conditions for bacterial growth. The results showed that the concentration of H2S emitted from the pumping station during 24 hours varied greatly between 0 and 48 PPM. The maximum adsorption capacity of the biological bedding was recorded at 2.874 g/m3.hr and the mean efficiency of H2S removal including the startup time was 89%. The mean performance efficiency during the biological activity after the startup was recorded at 98%.

  19. Odontoma: a retrospective study of 73 cases

    Energy Technology Data Exchange (ETDEWEB)

    An, Seo Young; An, Chang Hyeon; Choi, Karp Shik [School of Dentistry, Kyungpook National University, Daegu (Korea, Republic of)

    2012-06-15

    The purpose of the present study was to retrospectively evaluate the clinical findings and treatment results for impacted permanent teeth associated with odontomas. We retrospectively investigated 73 odontomas in 72 patients who visited Kyungpook National University Dental Hospital from April 2004 through November 2011. The study was performed using medical records, panoramic radiographs, and pathological reports. Data gathered included age, gender, location, chief complaints, effects on dentition, and treatment of odontoma and the impacted tooth associated with odontoma. Most compound odontomas (46.7%) were found in the second decade and complex odontomas were not related to age. Odontomas showed no gender predilection. Fifty-five cases (75.3%) of odontomas were detected on routine dental radiographs. Sixty percent of compound odontomas occurred in the canine area and 57.1% of complex odontomas in the molar areas. Impaction of permanent teeth (61.6%) was the most common complication on the adjacent teeth. Most odontomas (84.9%) were removed surgically and impacted permanent teeth were managed by surgical removal (53.2%), orthodontic treatment (25.5%), or surgical repositioning (6.4%). There was a statistically significant relation between age and preservation of the impacted permanent teeth associated with odontomas (p<0.01). Early detection and treatment of odontomas increase the possibility of preservation of the impacted tooth. Therefore, it would be suggested that periodic panoramic examination during the first and second decade of life might be beneficial for the early detection and better prognosis of odontomas.

  20. Anorexia in the Adolescence - case study

    Directory of Open Access Journals (Sweden)

    Almeida de Paiva, Maria O

    2010-07-01

    Full Text Available Eating disorders lead to special biological and psychological states. The result of the total lack of food is treated in a distinct way by anorexia. Nutritionists have thus had difficulty in coming to an agreement on the best therapy to prevent such disorders. First it is essential to understand which treatment aims are and then to attempt to know how the several treatment models used nowadays can reach those aims. Someone who suffers from eating disorders, together with an inner deformation, suffers from too much sensitiveness. In order to solve these problems, one needs a change in the relationship with oneself, with the others and with the world. This study presents a teenager’s case study – Anorexia. Is, in fact, a problem that society faces and can’t ignore. Many youngsters have already died and others are following their steps. But there are also those ones that succeeded in overcoming the problem and now are reporting their stories.

  1. Assembling a Case Study Tool Kit: 10 Tools for Teaching with Cases

    Science.gov (United States)

    Prud'homme-Généreux, Annie

    2017-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. The author shares the strategies and tools that teachers can use to manage a case study classroom effectively.

  2. Case Study: Camptocormia, a Rare Conversion Disorder.

    Science.gov (United States)

    Rajmohan, Velayudhan; Thomas, Biju; Sreekumar, Kumaran

    2004-01-01

    Camptocormia is a condition characterized by severe frontal flexion of the spinal cord and knees, with passive drooping of both arms. It occurs as a form of conversion disorder. Some cases are associated with behavioral problems. A case of camptocormia of 2-year duration in a south Indian adolescent girl with oppositional defiant disorder and…

  3. CROSSFIT – mental training. Case study

    Directory of Open Access Journals (Sweden)

    Beata Rolak

    2017-08-01

    Full Text Available Introduction: CrossFit is a challenging sport. It enforces full engagement of the athlete in every move during every training session. CrossFit teaches perseverance, discipline and respect. Sports psychology allows for in-depth analysis of trainings or competitions. The athlete can better prepare himself for what he may face, both on the mistakes made and on success. Regular mental training supports the athlete's ability to be successful in sports. The aim of the study: The purpose of this paper was to demonstrate the relationship between mental training - here mainly focused on concentration, self-confidence and imagery,  CrossFit and sports performance. Material and the method: This paper is a case study. The subject of the study was a male - 30 years old, training crossfit, with the 3-year training experience. Meeting  period with the subject male was conducted for 2 months. Before and after the meeting period there were used below mentioned methods: Sports Confidence Inventory (TSCI-PL; The Sport Anxiety Scale (SAS; The Imagination in Sport Questionnaire; The Sport  Orientation Questionnaire (SOQ and the profile of skills.   Results: There was a noticeable increase of the results in the questionnaires: Sports Confidence Inventory (TSCI-PL; The Imagination in Sport Questionnaire; The Sport  Orientation Questionnaire (SOQ questionnaire for the self-confidence (TSCI-PL.  The Sport Anxiety Scale (SAS there was an increase of the results regarding the somatic anxiety and worrying also there was a decrease in the scale of distraction. Conclusion: The meeting period turned out to be effective, however the mental training requires regularity and longevity in order to maintain consistency and repeatability of behavior.

  4. Teaching microbiological food safety through case studies

    Directory of Open Access Journals (Sweden)

    Florence Dubois-Brissonnet

    2015-10-01

    Full Text Available Higher education students usually ask for more training based on case studies. This was addressed by designing a specific food safety module (24 hours in which students were shown how to predict microbiological risks in food products i.e. they were asked to determine product shelf-life according to product formulation, preservation methods and consumption habits using predictive microbiology tools. Working groups of four students first identified the main microbiological hazards associated with a specific product. To perform this task, they were given several documents including guides for good hygiene practices, reviews on microbiological hazards in the food sector, flow sheets, etc…  After three-hours of work, the working groups prepared and gave an oral presentation in front of their classmates and professors. This raised comments and discussion that allowed students to adjust their conclusions before beginning the next step of their work. This second step consisted in the evaluation of the safety risk associated with the two major microbiological hazards of the product studied, using predictive microbiology. Students then attended a general lecture on the different tools of predictive microbiology and tutorials (6 hours that made them familiar with the modelling of bacterial growth or inactivation. They applied these tools (9 hours to predict the shelf-life of the studied product according to various scenarios of preservation (refrigeration, water activity, concentration of salt or acid, modified atmosphere, etc… and/or consumption procedures (cooking. The module was concluded by oral presentations of each working group and included student evaluation (3 hours.

  5. Zirconacyclopentadiene-annulated polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Kiel, Gavin R.; Ziegler, Micah S.; Tilley, T. Don

    2017-01-01

    Syntheses of large polycyclic aromatic hydrocarbons (PAHs) and graphene nanostructures demand methods that are capable of selectively and efficiently fusing large numbers of aromatic rings, yet such methods remain scarce. Herein, we report a new approach that is based on the quantitative intramolecular reductive cyclization of an oligo(diyne) with a low-valent zirconocene reagent, which gives a PAH with one or more annulated zirconacyclopentadienes (ZrPAHs). The efficiency of this process is demonstrated by a high-yielding fivefold intramolecular coupling to form a helical ZrPAH with 16 fused rings (from a precursor with no fused rings). Several other PAH topologies are also reported. Protodemetalation of the ZrPAHs allowed full characterization (including by X-ray crystallography) of PAHs containing one or more appended dienes with the ortho-quinodimethane (o-QDM) structure, which are usually too reactive for isolation and are potentially valuable for the fusion of additional rings by Diels-Alder reactions. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Zirconacyclopentadiene-annulated polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Kiel, Gavin R.; Ziegler, Micah S.; Tilley, T. Don [Department of Chemistry, University of California, Berkeley, CA (United States)

    2017-04-18

    Syntheses of large polycyclic aromatic hydrocarbons (PAHs) and graphene nanostructures demand methods that are capable of selectively and efficiently fusing large numbers of aromatic rings, yet such methods remain scarce. Herein, we report a new approach that is based on the quantitative intramolecular reductive cyclization of an oligo(diyne) with a low-valent zirconocene reagent, which gives a PAH with one or more annulated zirconacyclopentadienes (ZrPAHs). The efficiency of this process is demonstrated by a high-yielding fivefold intramolecular coupling to form a helical ZrPAH with 16 fused rings (from a precursor with no fused rings). Several other PAH topologies are also reported. Protodemetalation of the ZrPAHs allowed full characterization (including by X-ray crystallography) of PAHs containing one or more appended dienes with the ortho-quinodimethane (o-QDM) structure, which are usually too reactive for isolation and are potentially valuable for the fusion of additional rings by Diels-Alder reactions. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Jazz improvisers’ shared understanding: A case study

    Directory of Open Access Journals (Sweden)

    Michael F. Schober

    2014-08-01

    Full Text Available To what extent and in what arenas do collaborating musicians need to understand what they are doing in the same way? Two experienced jazz musicians who had never previously played together played three improvisations on a jazz standard (It Could Happen to You on either side of a visual barrier. They were then immediately interviewed separately about the performances, their musical intentions, and their judgments of their partner’s musical intentions, both from memory and prompted with the audiorecordings of the performances. Statements from both (audiorecorded interviews as well as statements from an expert listener were extracted and anonymized. Two months later, the performers listened to the recordings and rated the extent to which they endorsed each statement. Performers endorsed statements they themselves had generated more often than statements by their performing partner and the expert listener; their overall level of agreement with each other was greater than chance but moderate to low, with disagreements about the quality of one of the performances and about who was responsible for it. The quality of the performances combined with the disparities in agreement suggest that, at least in this case study, fully shared understanding of what happened is not essential for successful improvisation. The fact that the performers endorsed an expert listener’s statements more than their partner’s argues against a simple notion that performers’ interpretations are always privileged relative to an outsider’s.

  8. Comparative economic analysis: Anaerobic digester case study

    International Nuclear Information System (INIS)

    Lusk, P.D.

    1991-01-01

    An economic guide is developed to assess the value of anaerobic digesters used on dairy farms. Two varieties of anaerobic digesters, a conventional mixed-tank mesophilic and an innovative earthen psychrophilic, are comparatively evaluated using a cost-effectiveness index. The two case study examples are also evaluated using three other investment merit statistics: simple payback period, net present value, and internal rate of return. Life-cycle savings are estimated for both varieties, with sensitivities considered for investment risk. The conclusion is that an earthen psychrophilic digester can have a significant economic advantage over a mixed-tank mesophilic digester because of lower capital cost and reduced operation and maintenance expenses. Because of this economic advantage, additional projects are being conducted in North Carolina to increase the rate of biogas utilization. The initial step includes using biogas for milk cooling at the dairy farm where the existing psychrophilic digester is located. Further, a new project is being initiated for electricity production with thermal reclaim at a swine operation

  9. CFD analysis for road vehicles - case study

    Directory of Open Access Journals (Sweden)

    Eugen Mihai NEGRUS

    2011-09-01

    Full Text Available This is a case study on the influence of the lower part of road vehicles on the global drag characteristics. Reducing overall drag by redesigning the lower part of the road vehicles has a potential of almost 20% in the overall drag breakdown, mainly due to the viscous effects and the fluidic interaction of the flow under the car with the typical bluff body flow pattern behind the vehicle. A special parameterization is proposed for the global shape of the sedan car, with respect to the lower part of the body, taking into account most of the specificities of the system. For such a complex interaction, CFD analysis is probably the only efficient tool in order to assess specific design parameterization of a generic car shape. Building on the credibility of such instruments is one of the major goals of this paper. Also, with respect to a target sedan car configuration, examples of successful design strategies are presented. Based on the CFD results, possible strategies to be used in order to reduce viscous drag and global drag characteristics are proposed.

  10. Deep Energy Retrofits - Eleven California Case Studies

    Energy Technology Data Exchange (ETDEWEB)

    Less, Brennan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fisher, Jeremy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-10-01

    This research documents and demonstrates viable approaches using existing materials, tools and technologies in owner-conducted deep energy retrofits (DERs). These retrofits are meant to reduce energy use by 70% or more, and include extensive upgrades to the building enclosure, heating, cooling and hot water equipment, and often incorporate appliance and lighting upgrades as well as the addition of renewable energy. In this report, 11 Northern California (IECC climate zone 3) DER case studies are described and analyzed in detail, including building diagnostic tests and end-use energy monitoring results. All projects recognized the need to improve the home and its systems approximately to current building code-levels, and then pursued deeper energy reductions through either enhanced technology/ building enclosure measures, or through occupant conservation efforts, both of which achieved impressive energy performance and reductions. The beyond-code incremental DER costs averaged $25,910 for the six homes where cost data were available. DERs were affordable when these incremental costs were financed as part of a remodel, averaging a $30 per month increase in the net-cost of home ownership.

  11. Willowglen Systems Inc. : 8 case studies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The various supervisory control and data acquisition (SCADA) systems designed by Willowglen Systems Inc. were described. The company provides custom SCADA technology products, automation systems, and technical services for various applications. Their remote terminal units (RTUs) were designed to have a very low power consumption rate, and can be operated from any power source. The company has also designed integrated metering and communications solutions for remote locations. The following 8 case studies of Willowglen System solutions were highlighted: (1) a SCADA system designed for the Northwest Territories Power Corporation, (2) a system of RTUs installed at the Shell Canada Ltd. Caroline Gas Complex, (3) a SCADA system designed to monitor a natural gas pipeline, (4) a SCADA system designed to monitor a transmission pipeline and distribution system in Singapore, (5) RTUs designed to monitor gas dehydration units in Bahrain, (6) a SCADA system designed for a refined petroleum products pipeline, (7) a SCADA system installed at an electric power utility in New Brunswick, and (8) a tank gauging system designed for a large oil refinery in Alberta. 7 figs.

  12. Environmental injustice: case studies from the South

    International Nuclear Information System (INIS)

    Cifuentes, Enrique; Frumkin, Howard

    2007-01-01

    We selected three case studies to illustrate environmental injustice issues in the South. These examples relate to migrant agricultural workers, the maquiladora industry and artisanal mining, while reviewing some of the major mechanisms involved, e.g. multinational corporations, the development of free trade zones, multilateral free trade agreements and the export of hazards. A series of strategies are discussed in order to address environmental injustice and health disparities that exist on a global scale. Some of the recommendations involve policy initiatives; others, such as research and mentorship, fall within the traditional domain of public health practice. In this paper, special attention is given to concerned environmental and occupational health professionals using evidence-based data for advocacy. For lasting changes to be made, however, stronger institutions and legislation are required. Those who have the 'right to know' about environmental injustice issues include communities of concern, workers' representatives and lawyers. Government officials and company officials may eventually work on the basis of conflict resolution, compensation and remediation, to quote some examples. Systematic approaches to protect both the environment and public health must be updated

  13. Hyperamonemia in children. Study of 72 cases

    Directory of Open Access Journals (Sweden)

    Jiménez Pérez Mario

    2014-07-01

    Full Text Available Hyperammonemia (HA is a metabolic emergency, and when not diagnosed and treated in a timely manner leads to severe neuro- logical damage and/ or death. HA may have multiple origins, but the EIM are one of the causes that should always be suspected. The objective of this work is to make a clinical description of the causes of HA in a sample of patients from the National Institute of Pediatrics (INP, to know the proportion of patients with HA in which could confirm the presence of an inborn error of metabolism (IEM. We found 72 patients with HA in the past 10 years, of whom 11 were patients already known to have an IEM and 61 with unknown cause; Of the latter, 46% of patients underwent metabolic studies (amino acids quantification, organic acids analysis and orotic acid quantification and in 14 cases (30% an IEM was diagnosed. The clinical symptoms most frequently observed were neurological (seizures, drowsiness, lethargy, irritability, developmental delay, and hypotonia stupor, etc., followed by digestive disturbances such as vomiting and refusal to eat. Urea cycle disorders, aminoacidopathies and organic acidemias were diagnosed, so the management and treatment of these should be known by the pediatricians, especially those dedicated to emergencies.

  14. [Turner syndrome: Study of 42 cases].

    Science.gov (United States)

    Bahíllo-Curieses, M Pilar; Prieto-Matos, Pablo; Quiroga González, Rocío; Regueras Santos, Laura; Blanco Barrio, Amaya; Rupérez Peña, Sara

    2016-10-21

    Turner syndrome (TS) is characterized by short stature, gonadal dysgenesis, and total or partial loss of X chromosome. A historical cohorts study of patients with TS≤18 years old followed up in public hospitals in Castilla y Leon was undertaken. Forty-two female patients were included (prenatal diagnosis 11.9%, neonatal diagnosis 14.3%) with current median age 11.9±4.2 years. Short stature was the reason for consultation in 87.1%. Total monosomy of X chromosome was present in 40.5%. The most frequently associated comorbidity was opthalmological (50%), with heart defects in 23.8%. Ninety-three percent were treated with growth hormone (GH), mean age at the beginning of treatment was 7.43±3.4 years and mean height standard deviation was -2.84±1.08. Final height was reached in 10 patients only (mean final height 151.47±6.09cm). Chronological age of puberty induction was 13.2±0.94 years (bone age 12.47±1.17 years). Short stature was an important clinical sign for the diagnosis of TS, accompanied in some cases by other findings, with good response to GH treatment. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  15. Jazz improvisers' shared understanding: a case study.

    Science.gov (United States)

    Schober, Michael F; Spiro, Neta

    2014-01-01

    To what extent and in what arenas do collaborating musicians need to understand what they are doing in the same way? Two experienced jazz musicians who had never previously played together played three improvisations on a jazz standard ("It Could Happen to You") on either side of a visual barrier. They were then immediately interviewed separately about the performances, their musical intentions, and their judgments of their partner's musical intentions, both from memory and prompted with the audiorecordings of the performances. Statements from both (audiorecorded) interviews as well as statements from an expert listener were extracted and anonymized. Two months later, the performers listened to the recordings and rated the extent to which they endorsed each statement. Performers endorsed statements they themselves had generated more often than statements by their performing partner and the expert listener; their overall level of agreement with each other was greater than chance but moderate to low, with disagreements about the quality of one of the performances and about who was responsible for it. The quality of the performances combined with the disparities in agreement suggest that, at least in this case study, fully shared understanding of what happened is not essential for successful improvisation. The fact that the performers endorsed an expert listener's statements more than their partner's argues against a simple notion that performers' interpretations are always privileged relative to an outsider's.

  16. Case study : a transformer repair facility

    Energy Technology Data Exchange (ETDEWEB)

    Jerade, L. [Jacques Whitford Environment Ltd., Vancouver, BC (Canada)

    2006-07-01

    Polychlorinated biphenyls (PCBs) are synthetic chemical compounds consisting of chlorine, carbon and hydrogen. They are very stable, fire resistant, do not conduct electricity and have low volatility at normal temperatures. They were mainly used as a cooling and insulating fluid for industrial transformers and capacitors. Some of the same properties that made PCBs so widely used, also make them environmentally hazardous, especially their extreme resistance to chemical and biological breakdown by natural processes in the environment. Typical chemicals associated with the presence of PCB oils are chlorobenzene, lead, xylene, and petroleum hydrocarbons. A case study of a transformer repair facility was discussed along with its soil and groundwater remediation. This presentation discussed the delineation program for the site which operated as a repair facility of PCB-containing transformers from 1968 until 1998. The property was bought by Siemens Canada Ltd. in 1998 and was sold in 2004. As part of the purchasing agreement, a Certificate of Compliance from the British Columbia Ministry of Environment was required. Remediation work was therefore needed. The presentation also covered: zones of contamination and contaminants of concern, soil impacts, groundwater impacts, and an evaluation of remediation options. In-situ treatment of soil with hydrogen peroxide and the selected remedial option were discussed. A soil economic analysis was also conducted. Last, challenges, solutions, and conclusions were presented. tabs., figs.

  17. Hybrid Risk Management Methodology: A Case Study

    Directory of Open Access Journals (Sweden)

    Jacky Siu-Lun Ting

    2009-10-01

    Full Text Available Risk management is a decision-making process involving considerations of political, social, economic and engineering factors with relevant risk assessments relating to a potential hazard. In the last decade, a number of risk management tools are introduced and employed to manage and minimize the uncertainty and threats realization to the organizations. However, the focus of these methodologies are different; in which companies need to adopt various risk management principles to visualize a full picture of the organizational risk level. Regarding to this, this paper presents a new approach of risk management that integrates Hierarchical Holographic Modeling (HHM, Enterprise Risk Management (ERM and Business Recovery Planning (BCP for identifying and assessing risks as well as managing the consequences of realized residual risks. To illustrate the procedures of the proposed methodology, a logistic company ABC Limited is chosen to serve as a case study Through applying HHM and ERM to investigate and assess the risk, ABC Limited can be better evaluated the potential risks and then took the responsive actions (e.g. BCP to handle the risks and crisis in near future.

  18. Environmental injustice: case studies from the South

    Science.gov (United States)

    Cifuentes, Enrique; Frumkin, Howard

    2007-10-01

    We selected three case studies to illustrate environmental injustice issues in the South. These examples relate to migrant agricultural workers, the maquiladora industry and artisanal mining, while reviewing some of the major mechanisms involved, e.g. multinational corporations, the development of free trade zones, multilateral free trade agreements and the export of hazards. A series of strategies are discussed in order to address environmental injustice and health disparities that exist on a global scale. Some of the recommendations involve policy initiatives; others, such as research and mentorship, fall within the traditional domain of public health practice. In this paper, special attention is given to concerned environmental and occupational health professionals using evidence-based data for advocacy. For lasting changes to be made, however, stronger institutions and legislation are required. Those who have the 'right to know' about environmental injustice issues include communities of concern, workers' representatives and lawyers. Government officials and company officials may eventually work on the basis of conflict resolution, compensation and remediation, to quote some examples. Systematic approaches to protect both the environment and public health must be updated.

  19. MOTION TO CHANGE VENUE. CASE STUDY

    Directory of Open Access Journals (Sweden)

    Dragoş Lucian Rădulescu

    2015-11-01

    Full Text Available Change of venue is a remedy offered to a party, which in case of legitimate grounds for suspicion or public safety may require that proceedings belong to another court than the court first seized. But change of venue is not based on a case of material or territorial lack of jurisdiction of the court, taking into account exceptional circumstances or impartiality doubt regarding the case. Thus, article 140 of the Code of Civil Procedure stipulates the possible causes of change of venue, including further issues that will determine jurisdiction to hear by the courts of control.

  20. Guidelines for Conducting Positivist Case Study Research in Information Systems

    Directory of Open Access Journals (Sweden)

    Graeme Shanks

    2002-11-01

    Full Text Available The case study research approach is widely used in a number of different ways within the information systems community. This paper focuses on positivist, deductive case study research in information systems. It provides clear definitions of important concepts in positivist case study research and illustrates these with an example research study. A critical analysis of the conduct and outcomes of two recently published positivist case studies is reported. One is a multiple case study that validated concepts in a framework for viewpoint development in requirements definition. The other is a single case study that examined the role of social enablers in enterprise resource planning systems implementation. A number of guidelines for successfully undertaking positivist case study research are identified including developing a clear understanding of key concepts and assumptions within the positivist paradigm; providing clear and unambiguous definitions of the units and interactions when using any theory; carefully defining the boundary of the theory used in the case study; using hypotheses rather than propositions in the empirical testing of theory; using fuzzy or probabilistic propositions in recognising that reality can never be perfectly known; selecting case studies carefully, particularly single case studies; and recognising that generalisation from positivist, single case studies is inherently different from generalisation from single experiments. When properly undertaken, positivist, deductive case study research is a valuable research approach for information systems researchers, particularly when used within pluralist research programs that use a number of different research approaches from different paradigms.

  1. Bilingual education in Slovakia: A Case Study

    Directory of Open Access Journals (Sweden)

    Silvia Pokrivčáková

    2013-06-01

    Full Text Available Bilingual education is one of the areas in contemporary education that brings out some important controversies (philosophical, conceptual, sociological, political, economical, etc. and thus calls for extensive and intensive debate. Bilingual education in Europe (and here the European Union countries are meant has gained a very different status, due to the general European policy of developing language diversity and promoting “European plurilingualism and multilingualism”. In Slovakia, one of the younger members of the EU, bilingual education became an extraordinarily popular instrument for the fulfilment of this task.  Since the specifically defined topic of bilingual education and its current status in Slovakia has not been studied and systematically reviewed yet, the research presented in this paper was designed as a single-phenomenon revelatory case study investigating seven research areas: reflection of bilingual education in school legislation and state pedagogical documents, purposes of bilingual education in Slovakia, its organization (levels and types of schools, foreign languages incorporated, teachers, structure of bilingual schools curricula, types of bilingual education applied at Slovak bilingual schools, and how bilingual education is both reflected in and saturated by the latest research findings. The conclusions presented in the paper were collected from multiple sources: state curriculum, statistical data published by the Slovak Ministry of Education or its partner institutions, international treaties on establishing and supporting bilingual sections of schools, bilingual schools curricula, interviews with school directors, teachers, and learners, direct observations at bilingual schools, research studies and research reports, etc. In the conclusion, bilingual education in Slovakia is identified as a unique, dynamically developing system which is both significantly shaped by the foreign language education policy promoted by

  2. Polymorphisms in the xenobiotic transporter Multidrug Resistance 1 (MDR1) and interaction with meat intake in relation to risk of colorectal cancer in a Danish prospective case-cohort study

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Østergaard, Mette; Christensen, Jane

    2009-01-01

    (rs5275) polymorphisms in the 3'-untranslated region. The polymorphisms were assessed together with lifestyle factors in a nested case-cohort study of 359 cases and a random cohort sample of 765 participants from the Danish prospective Diet, Cancer and Health study. Results Carriers of the variant......Background The xenobiotic transporters, Multidrug Resistance 1 (MDR1/ABCB1) and Breast Cancer Resistance Protein (BCRP/ABCG2) may restrict intestinal absorption of various carcinogens, including heterocyclic amines (HCA) and polycyclic aromatic hydrocarbons (PAH). Cyclooxygenase-2 (COX-2) derived...... prostaglandins promote gastrointestinal carcinogenesis, affecting angiogenesis, apoptosis, and invasiveness. The aim of this study was to investigate if polymorphisms in these genes were associated with risk of colorectal cancer (CRC), and to investigate possible interactions with lifestyle factors...

  3. Investigations of material balance and the formation of metabolites on white rot in clamps in soil loaded with polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Zarth, M.

    1993-01-01

    One examines from a concrete case to what extent the potential danger of white rot in bio-beds caused by polycyclic aromatic hydrocarbons (PAH's) is reduced. The potential danger is mainly determined by the remainder of the PAH's. The remainder paths to be considered (micro-biological decomposition, transport and abiotic processes) are shown. (orig.) [de

  4. Jane: A Case Study in Anorexia Nervosa.

    Science.gov (United States)

    Willingham, Barbara

    1988-01-01

    The article reports the case history of a 15-year-old Australian girl with anorexia nervosa. Information is also given on prevalence, causes, definitions, and treatments including hospitalization, co-therapy, psychotherapy, behavior modification, family therapy, and counseling. (DB)

  5. Case Study Research in Software Engineering Guidelines and Examples

    CERN Document Server

    Runeson, Per; Rainer, Austen; Regnell, Bjorn

    2012-01-01

    Based on their own experiences of in-depth case studies of software projects in international corporations, in this book the authors present detailed practical guidelines on the preparation, conduct, design and reporting of case studies of software engineering.  This is the first software engineering specific book on the case study research method.

  6. Urinary 1-hydroxypyrene as a biomarker to carcinogenic polycyclic aromatic hydrocarbon exposure.

    Science.gov (United States)

    Ifegwu, Clinton; Osunjaye, Kayode; Fashogbon, Folasade; Oke, Kolawole; Adeniyi, Afolabi; Anyakora, Chimezie

    2012-01-01

    In order to capture the extent of exposure to polycyclic aromatic hydrocarbons (PAHs), various biomarkers have been employed. The biomarkers employed for PAHs include PAHs genetoxic end points in lymphocytes, urinary metabolites, PAH-DNA adducts, and PAH-Protein adducts. Of these, excretory 1-hydroxypyene, a metabolite of pyrene, has been used extensively as a biological monitoring indicator of exposure to PAHs. This study attempts to assess the level of this biomarker in the body fluid of 68 exposed subjects using high performance liquid chromatography HPLC. The subjects screened included auto mechanics, drivers, and fuel attendants. 1-hydroxypyrene was extracted from the urine of the subjects using solid phase extraction method. The HPLC analysis was done in isocratic mode using water:methanol (12:88 v/v) mobile phase. The stationary phase was XBridge C18 (150 × 4.6 mm) 5 μm column. The wavelength was 250 nm at a flow rate of 1.2 mL/min. The oven temperature was 30 ºC and the injection volume was 20 μL. The run time was 3 minutes. The level of urinary 1-hydroxypyrene detected varied for the different categories of occupation studied. About 27% of sampled fuel attendants and 22% of auto mechanics had detectable 1-hydroxypyrene in their urine samples. There was no detectable 1-hydroxypyene in the urine samples of commercial drivers or in the urine samples of students used as controls. The results of this study showed that fuel attendants and auto mechanics have significant exposures to PAHs. So far, there is no established benchmark for level of PAHs in urine, but our findings indicate the possibility of future cancer cases in this population as a result of their occupational exposure. The study was not able to link the level of 1-hydroxypyene with the smoking habits of the subjects.

  7. Urinary 1-Hydroxypyrene as a Biomarker to Carcinogenic Polycyclic Aromatic Hydrocarbon Exposure

    Directory of Open Access Journals (Sweden)

    Clinton Ifegwu

    2012-01-01

    Full Text Available In order to capture the extent of exposure to polycyclic aromatic hydrocarbons (PAHs, various biomarkers have been employed. The biomarkers employed for PAHs include PAHs genetoxic end points in lymphocytes, urinary metabolites, PAH-DNA adducts, and PAH-Protein adducts. Of these, excretory 1-hydroxypyene, a metabolite of pyrene, has been used extensively as a biological monitoring indicator of exposure to PAHs. This study attempts to assess the level of this biomarker in the body fluid of 68 exposed subjects using high performance liquid chromatography HPLC. The subjects screened included auto mechanics, drivers, and fuel attendants. 1-hydroxypyrene was extracted from the urine of the subjects using solid phase extraction method. The HPLC analysis was done in isocratic mode using water:methanol (12:88 v/v mobile phase. The stationary phase was XBridge C18 (150 × 4.6 mm 5 μm column. The wavelength was 250 nm at a flow rate of 1.2 mL/min. The oven temperature was 30 °C and the injection volume was 20 μL. The run time was 3 minutes. The level of urinary 1-hydroxypyrene detected varied for the different categories of occupation studied. About 27% of sampled fuel attendants and 22% of auto mechanics had detectable 1-hydroxypyrene in their urine samples. There was no detectable 1-hydroxypyene in the urine samples of commercial drivers or in the urine samples of students used as controls. The results of this study showed that fuel attendants and auto mechanics have significant exposures to PAHs. So far, there is no established benchmark for level of PAHs in urine, but our findings indicate the possibility of future cancer cases in this population as a result of their occupational exposure. The study was not able to link the level of 1-hydroxypyene with the smoking habits of the subjects.

  8. Cases for the Net Generation: An Empirical Examination of Students' Attitude toward Multimedia Case Studies

    Science.gov (United States)

    Sheppard, Michael; Vibert, Conor

    2016-01-01

    Case studies have been an important tool in business, legal, and medical education for generations of students. Traditional text-based cases tend to be self-contained and structured in such a way as to teach a particular concept. The multimedia cases introduced in this study feature unscripted web-hosted video interviews with business owners and…

  9. Teaching Business French through Case Studies: Presentation of a Marketing Case.

    Science.gov (United States)

    Federico, Salvatore; Moore, Catherine

    The use of case studies as a means for teaching business French is discussed. The approach is advocated because of the realism of case studies, which are based on actual occurrences. Characteristics of a good case are noted: it tells a story, focuses on interest-arousing issues, is set in the past 10 years, permits empathy with the main…

  10. Case Study: What Makes a Good Case, Revisited: The Survey Monkey Tells All

    Science.gov (United States)

    Herried, Clyde Freeman; Prud'homme-Genereux, Annie; Schiller, Nancy A.; Herreid, Ky F.; Wright, Carolyn

    2016-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. In this month's issue the authors provide a more definitive answer to the "What Makes a Good Case?" question based on a just-completed Survey Monkey survey given to NCCSTS teachers.

  11. Increasing transmission capacity : case studies and techniques

    Energy Technology Data Exchange (ETDEWEB)

    Reisdorff, R.A. [Laminated Wood Systems, NE (United States)

    2007-07-01

    Many companies are stretching the capacities of their mature transmission lines as a result of deregulation in the electric utility industry. Since electric utilities are no longer in control of new generation locations or capacities, their mission has changed from supplying electricity to regional customers to that of the movement of power over their grid. There will also be even more pressure to maximize the thermal capacity of existing transmission lines once the regional transmission operators (RTOs) are in place. Various methods including conductor replacement or increasing structure height are available options to accomplish this. This paper discussed the available methods to increase ground clearance, including structure changeouts; pole top extensions; nip and tuck conductor; adding mid-span structures; and raising structures. Because the actual cost of line outages for maintenance of rebuild work will make many present day work procedures obsolete, the industry is changing to methods of safely increasing the existing structure heights without removing the line from service. The paper also presented the Phaiseraiser product which is a patented system, consisting of double steel members that are either single or multiple piece units which are used to support the raised structure. The paper discussed the product development of the Phaiseraiser product, with reference to wood stubs; pier foundation; pole enforcer methodology; testing; designs; and ordering requirements. Last, the paper discussed a custom designed installation tool package developed by Laminated Wood Systems (LWS); LWS structural analysis; estimated cost for Phaiseraiser installation on an h-frame; labor resources and training; maintenance considerations; completed Phaiseraiser projects; and a case study on the Omaha Public Power District. figs.

  12. Zimbabwe's national AIDS levy: A case study.

    Science.gov (United States)

    Bhat, Nisha; Kilmarx, Peter H; Dube, Freeman; Manenji, Albert; Dube, Medelina; Magure, Tapuwa

    2016-01-01

    We conducted a case study of the Zimbabwe National AIDS Trust Fund ('AIDS Levy') as an approach to domestic government financing of the response to HIV and AIDS. Data came from three sources: a literature review, including a search for grey literature, review of government documents from the Zimbabwe National AIDS Council (NAC), and key informant interviews with representatives of the Zimbabwean government, civil society and international organizations. The literature search yielded 139 sources, and 20 key informants were interviewed. Established by legislation in 1999, the AIDS Levy entails a 3% income tax for individuals and 3% tax on profits of employers and trusts (which excluded the mining industry until 2015). It is managed by the parastatal NAC through a decentralized structure of AIDS Action Committees. Revenues increased from inception to 2006 through 2008, a period of economic instability and hyperinflation. Following dollarization in 2009, annual revenues continued to increase, reaching US$38.6 million in 2014. By policy, at least 50% of funds are used for purchase of antiretroviral medications. Other spending includes administration and capital costs, HIV prevention, and monitoring and evaluation. Several financial controls and auditing systems are in place. Key informants perceived the AIDS Levy as a 'homegrown' solution that provided country ownership and reduced dependence on donor funding, but called for further increased transparency, accountability, and reduced administrative costs, as well as recommended changes to increase revenue. The Zimbabwe AIDS Levy has generated substantial resources, recently over US$35 million per year, and signals an important commitment by Zimbabweans, which may have helped attract other donor resources. Many key informants considered the Zimbabwe AIDS Levy to be a best practice for other countries to follow.

  13. Simpson's paradox: A statistician's case study.

    Science.gov (United States)

    Chu, Kevin H; Brown, Nathan J; Pelecanos, Anita; Brown, Anthony Ft

    2018-02-26

    Gender equality and workforce diversity has recently been in the forefront of College discussions. Reasons for the difference between various groups may not be as they initially appeared. The results of comparing the outcome between two groups can sometimes be confounded and even reversed by an unrecognised third variable. This concept is known as Simpson's Paradox, and is illustrated here using a renowned case study on potential gender bias for acceptance to Graduate School at the University of California, Berkeley.  The investigation showed that males were 1.8 times more likely to be admitted to Graduate School than females in 1973. Initially it appeared that women were discriminated against in the selection process. However, when admissions were re-examined at individual Departments of the School, admission tended to be better for women than men in four of six Departments. This contradiction or paradox tells us that the association between admission and gender was dependent upon on Department.  The confounding effect of Department was defined by two characteristics. Firstly, a strong association between Department and admission: some Departments admitted much smaller percentages of applicants than others. Secondly, a strong association between Department and gender: females tended to apply to Departments with lower admission rates.  The explanation of differences between groups can be multifactorial. A search for possible confounders will assist in this understanding. This could apply whenever two groups initially appear to differ, but on closer analysis this difference is either unfounded, or even reversed by reference to a third, confounding variable. © 2018 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  14. Determination of hydroxylated polycyclic aromatic hydrocarbons by HPLC-photoionization tandem mass spectrometry in wood smoke particles and soil samples.

    Science.gov (United States)

    Avagyan, Rozanna; Nyström, Robin; Boman, Christoffer; Westerholm, Roger

    2015-06-01

    A simple and fast method for analysis of hydroxylated polycyclic aromatic hydrocarbons using pressurized liquid extraction and high performance liquid chromatography utilizing photoionization tandem mass spectrometry was developed. Simultaneous separation and determination of nine hydroxylated polycyclic aromatic hydrocarbons and two hydroxy biphenyls could be performed in negative mode with a run time of 12 min, including equilibration in 5 min. The calibration curves were in two concentration ranges; 1-50 ng/mL and 0.01-50 μg/mL, with coefficients of correlation R (2) > 0.997. The limits of detection and method quantification limits were in the range of 9-56 pg and 5-38 ng/g, respectively. A two-level full factorial experimental design was used for screening of conditions with the highest impact on the extraction. The extraction procedure was automated and suitable for a large number of samples. The extraction recoveries ranged from 70 to 102 % and the matrix effects were between 92 and 104 %. The overall method was demonstrated on wood smoke particles and soil samples with good analytical performance, and five OH-PAHs were determined in the concentration range of 0.19-210 μg/g. As far as we know, hydroxylated polycyclic aromatic hydrocarbons were determined in wood smoke and soil samples using photoionization mass spectrometry for the first time in this present study. Accordingly, this study shows that high performance liquid chromatography photoionization tandem mass spectrometry can be a good option for the determination of hydroxylated polycyclic aromatic hydrocarbons in complex environmental samples. Graphical Abstract The method developed in this study was used to determine hydroxylated polycyclic aromatic hydrocarbons in wood smoke and soil.

  15. Polycyclic aromatic hydrocarbons in Bangladeshi vegetables and fruits.

    Science.gov (United States)

    Hossain, M Amzad; Hoque, Mohammad Zahirul

    2011-01-01

    Polycyclic aromatic hydrocarbons (PAHs) occur as contaminants in different types of food predominantly from environmental pollution, food packaging and food processing and the levels found depend on the source of the contamination. PAHs emissions from automobile traffic and industry activities were shown to influence the PAHs levels and profiles in vegetables and fruits grown nearby. The present study was carried out to determine the levels of PAHs in samples of tomato, cabbage and apple, collected from six different places of urban and rural areas of plantation in Dhaka city. Eight PAHs listed in the priority pollutant of US Environment Protection Agency and regarded as carcinogens were analyzed in this study. The analytical method involved saponification with methanolic KOH, liquid-liquid extraction with cyclohexane, clean-up on silica gel column and determination by Gas chromatography and mass spectrometry. The mean levels of total PAHs were 9.50 μg/kg in tomato, 8.86 μg/kg in cabbage and 4.05 μg/kg in apple. Of the carcinogenic PAHs, benzo(a)anthracene was the most representative, being found in 89% of all samples analysed. Chrysene was not detected in any sample. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Occupational exposure to Polycyclic Aromatic Hydrocarbons in wood dust

    International Nuclear Information System (INIS)

    Huynh, C K; Schuepfer, P; Boiteux, P

    2009-01-01

    Sino-nasal cancer (SNC) represents approximately 3% of Oto-Rhino-Laryngology (ORL) cancers. Adenocarcinoma SNC is an acknowledged occupational disease affecting certain specialized workers such as joiners and cabinetmakers. The high proportion of woodworkers contracting a SNC, subjected to an estimated risk 50 to 100 times higher than that affecting the general population, has suggested various study paths to possible causes such as tannin in hardwood, formaldehyde in plywood and benzo(a)pyrene produced by wood when overheated by cutting tools. It is acknowledged that tannin does not cause cancer to workers exposed to tea dust. Apart from being an irritant, formaldehyde is also classified as carcinogenic. The path involving carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) emitted by overheated wood is attractive. In this study, we measured the particle size and PAHs content in dust emitted by the processing of wood in an experimental chamber, and in field situation. Quantification of 16 PAHs is carried out by capillary GC-ion trap Mass Spectrometric analysis (GC-MS). The materials tested are rough fir tree, oak, impregnated polyurethane (PU) oak. The wood dust contains carcinogenic PAHs at the level of μg.g -1 or ppm. During sanding operations, the PU varnish-impregnated wood produces 100 times more PAHs in dust than the unfinished wood.

  17. Occupational exposure to Polycyclic Aromatic Hydrocarbons in wood dust

    Energy Technology Data Exchange (ETDEWEB)

    Huynh, C K; Schuepfer, P; Boiteux, P, E-mail: chuynh@hospvd.c [Institute for Work and Health, rue du Bugnon 21, CH-1005 Lausanne (Switzerland)

    2009-02-01

    Sino-nasal cancer (SNC) represents approximately 3% of Oto-Rhino-Laryngology (ORL) cancers. Adenocarcinoma SNC is an acknowledged occupational disease affecting certain specialized workers such as joiners and cabinetmakers. The high proportion of woodworkers contracting a SNC, subjected to an estimated risk 50 to 100 times higher than that affecting the general population, has suggested various study paths to possible causes such as tannin in hardwood, formaldehyde in plywood and benzo(a)pyrene produced by wood when overheated by cutting tools. It is acknowledged that tannin does not cause cancer to workers exposed to tea dust. Apart from being an irritant, formaldehyde is also classified as carcinogenic. The path involving carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) emitted by overheated wood is attractive. In this study, we measured the particle size and PAHs content in dust emitted by the processing of wood in an experimental chamber, and in field situation. Quantification of 16 PAHs is carried out by capillary GC-ion trap Mass Spectrometric analysis (GC-MS). The materials tested are rough fir tree, oak, impregnated polyurethane (PU) oak. The wood dust contains carcinogenic PAHs at the level of mug.g{sup -1} or ppm. During sanding operations, the PU varnish-impregnated wood produces 100 times more PAHs in dust than the unfinished wood.

  18. Uptake, translocation, and accumulation of polycyclic aromatic hydrocarbons in vegetation

    International Nuclear Information System (INIS)

    Walton, B.T.; Hoylman, A.M.

    1992-12-01

    A review of the scientific literature was conducted to determine the potential for plants to take up polycyclic aromatic hydrocarbons (PAHs) from soils and the possibility of PAH movement from soils into vegetation at waste disposal sites associated with manufactured gas plants (MGP). Studies published since 1983 are considered in conjunction with previous publications and literature reviews on PAH uptake by vegetation. These studies indicate that the extent to which sorption to roots occurs is likely to be influenced by species-specific properties of the plant, physicochemical properties of each PAH, soil properties, and biodegradation rates of the PAHs in soil. PAHs containing five or more rings may sorb to plant roots but are not expected to be translocated to foliage in other than trace quantities. Uptake of naphthalene, anthracene, and benzo[a]anthracene by roots has been reported in the literature. In addition, eight PAHs of three and four rings (acenapthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, and chrysene) were isolated from leaves and roots of four plant species collected near a coal tar disposal trench in eastern Tennessee. A total concentration of 5519 ng/g was observed for the eight PAHs in roots of lamb's quarters. Coal tar, in soil, was implicated as the source of PAHs in the four plant species

  19. Determination of Polycyclic Aromatic Hydrocarbons In Exhaled Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Moldoveanu SC

    2014-12-01

    Full Text Available The retention by humans of 20 polycyclic aromatic hydrocarbons (PAHs from mainstream cigarette smoke was evaluated. The analysis was done by a new technique using solid phase extraction (SPE for the cleanup and the concenration of PAHs. The new technique has excellent sensitivity and accuracy, which were necessary for the analysis of the very low levels of PAHs present in the exhaled cigarette smoke. The study was done on a common commercial cigarette with 10.6 mg ‘tar’ by U.S. Federal Trade Commission (FTC recommendation. The results were obtained from ten human subjects, each smoking three cigarettes. The exhaled smoke was collected using a vacuum assisted procedure that avoids strain in exhaling. The study showed that the PAHs with a molecular weight lower than about 170 Daltons are retained with high efficiency. The heavier molecules are less retained, but even compounds such as indeno[1,2,3-cd]pyrene, dibenz[a, h]anthracene, and benzoperylene are retained with efficiencies around 50%. The dependence of retention efficiency for PAHs (in % on their octanol-water partition coefficient (LogPow was found to be nonlinear and showed considerable variability for several compounds that have very close LogPow values. Better correlation was obtained between the retention efficiency and PAHs vapor pressure (Log VP.

  20. Polycyclic aromatic hydrocarbons and cytochrome P450 in HIV pathogenesis

    Science.gov (United States)

    Rao, P. S. S.; Kumar, Santosh

    2015-01-01

    High prevalence of cigarette smoking in HIV patients is associated with increased HIV pathogenesis and disease progression. While the effect of smoking on the occurrence of lung cancer has been studied extensively, the association between smoking and HIV pathogenesis is poorly studied. We have recently shown the possible role of cytochrome P450 (CYP) in smoking/nicotine-mediated viral replication. In this review, we focus on the potential role of CYP pathway in polycyclic aromatic hydrocarbons (PAH), important constituents of cigarette smoke, mediated HIV pathogenesis. More specifically, we will discuss the role of CYP1A1 and CYP1B1, which are the major PAH-activating CYP enzymes. Our results have shown that treatment with cigarette smoke condensate (CSC) increases viral replication in HIV-infected macrophages. CSC contains PAH, which are known to be activated by CYP1A1 and CYP1B1 into procarcinogens/toxic metabolites. The expression of these CYPs is regulated by aryl hydrocarbon receptors (AHR), the cellular target of PAH, and an important player in various diseases including cancer. We propose that PAH/AHR-mediated CYP pathway is a novel target to develop new interventions for HIV positive smokers. PMID:26082767