498 research outputs found

    Skeletal concentrations of lead, cadmium, zinc, and silver in ancient North American Pecos Indians.

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    Bone samples of 14 prehistoric North American Pecos Indians from circa 1400 A.D. were analyzed for lead, cadmium, zinc, and silver by graphite furnace atomic absorption spectrometry to establish the baseline levels of these elements in an ancient North American population. Measurements of outer and inner bone fractions indicate the former were contaminated postmortem for lead, zinc, and cadmium. The contamination-adjusted average (mean +/- SD) level of lead (expressed as the ratio of atomic lead to atomic calcium) in bones of the Indians was 8.4 +/- 4.4 x 10(-7)), which was similar to ratios in bones of ancient Peruvians (0.9 to 7.7 x 10(-7)) and significantly lower than ratios in bones of modern adults in England and the United States (210 to 350 x 10(-7]. The adjusted average concentrations (microgram per gram dry weight) of biologic cadmium, silver, and zinc in the Pecos Indian bones were 0.032 +/- 0.013, 0.094 +/- 0.044, and 130 +/- 66, as compared to concentrations of 1.8, 0.01 to 0.44, and 75 to 170 in the bones of modern people, respectively. Therefore, cadmium concentrations in Pecos Indian bones are also approximately 50-fold lower than those of contemporary humans. These data support earlier findings that most previously reported natural concentrations of lead in human tissues are erroneously high and indicate that natural concentrations of cadmium are also between one and two orders of magnitude lower than contemporary concentrations

    Polymorphisms in MGP gene and their association with lead toxicity

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    Matrix γ-carboxy glutamic acid protein (MGP) is a 10-kDa secreted protein containing five residues of the vitamin K-dependent calcium binding amino acid γ-carboxyglutamic acid (Gla). This study was carried out to examine the effects of MGP gene promoter polymorphism (T-138C) on blood lead levels (BLL) and hematological parameters in 113 battery manufacturing unit workers occupationally exposed to lead and 102 controls. Genotypes for the MGP T-138C polymorphism were determined by PCR and restriction fragment length digestion. BLL were determined by Anode Stripping Voltammetry using ESA Model 3010B Lead analyzer. Complete blood picture (CBP) was analyzed using ADVIA Cell counter for each sample. The frequencies of MGP–TT, CT and CC genotypes in our population were 38.6%, 44.3%, and 17.2%, respectively. The frequencies for T and C alleles were 0.612 and 0.386, respectively. Although BLL did not differ significantly among genotypes; they were higher in workers with TT/CT genotype compared to CC genotype subjects (76–88 μg/dL vs 22–45 μg/dL, p > 0.05). About 29.2% of volunteers (n = 33) from the occupationally exposed group had hemoglobin levels below 10.0 gms/dl. There was no significant difference in total white cell count and platelet count between occupational and non-exposed groups. The possible role of SNPs in the promoter region of MGP gene with relation to lead toxicity was investigated for the first time in the Indian population; although significance could not be achieved in this study, further assessments over a larger population size may help in better understanding of the consequences of lead exposure

    Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era

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    Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country’s late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 µg·g−1), than black males (ME = 3.80 µg·g−1) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead

    Protection of Domestic bank Ownership in France and Germany: The Functional Equivalency of Institutional Diversity in Takeovers

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    We investigate the character of the market for corporate control (i.e. takeovers) in French and German banking. The key feature of this character is the marked ability of French and German banks to resist unsolicited takeover bids, especially – although not exclusively– those from foreign competitors. We present an institutional perspective to account for the restrained character of takeovers in French and German banking. Our perspective is composed of two elements. First, institutional arrangements are important since they structure power relations among firm stakeholders by providing opportunities, as well as imposing constraints, to influence the decision-making process in which takeover transactions take place. Second, institutional arrangements provide firm stakeholders with several potential opportunities, not just one, to block unsolicited bids since takeover contests are composed of sequences of decisions for which approval is needed at each stage. French and German banks have used different mixes of institutional arrangements, themselves located at different stages of takeover transactions, to secure restrained markets for corporate control. Our institutional analysis, in turn, also illustrates an important shortcoming of banking sector protectionism, namely the contribution of protection from unsolicited takeover bids to the building of banks carrying systemic risks

    Time Course of the Neural Activity Related to Behavioral Decision-Making as Revealed by Event-Related Potentials

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    Objective: To study the time course of the electrocortical activity evoked by gains and losses in the Iowa Gambling Task (IGT), the brain sources of this electrical activity, and its association with behavioral parameters of task performance in order to achieve a better knowledge of decision-making processes. Method: Event-related potentials (ERPs) were obtained from a 64-channel EEG in 25 participants when performing the IGT. Brain source localization analyses of the ERP components were also assessed. Results: ERP amplitudes were sensitive to gains and losses. An early fronto-central negativity was elicited when feedback was provided for both gains and losses, and correlated with the number of gains at FCz and with the number of both gains and losses at Cz. The P200 component had larger amplitudes to losses and correlated positively with the number of losses. Feedback related negativity (FRN) was higher at frontal, temporal and occipital electrodes in trials with monetary losses. In addition, trials with monetary losses elicited larger P300 magnitudes than trials with monetary gains at all electrode localizations. Conclusions: All ERP components (except P300) were related to participants’ performance in the IGT. Amplitudes of P200 and P300 were associated with the conscious recognition of the error during the decision-making. Performance data and source analysis underline the importance of the medial prefrontal cortex when processing feedback about monetary losses in the IGT.This research was supported by grants from the Spanish Ministry of Science and Innovation (Ministerio de Ciencia y Tecnología), European Regional Development Funds (ERDF) and Ministry of Economy, Industry and Competitiveness (Ministerio de Economía, Industria y Competitividad, Gobierno de España). References: PSI2008-04394, PSI2017-88388-C4-1-R and PSI2017-88388-C4-3-R

    Pristup procjeni zdravstvenoga rizika za ljude prilikom izgradnje gradskoga parka

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    A Human Health Risk Assessment (HHRA) was undertaken for a proposed park development “River Landing”, to be constructed along the north bank of the South Saskatchewan River in the City of Saskatoon, Saskatchewan, Canada. The purpose of the HHRA was to determine whether chemical constituents identified at the site, including polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons (PHCs), and toxic and heavy metals, would adversely affect the health of construction workers and potential park users. Although more traditional remediation options were considered, the risk assessment approach was chosen since it represented the best available technology. The HHRA was undertaken using protocols and methodologies proposed and readily accepted by the Canadian Council of Ministers of the Environment (CCME), Health Canada, and the United States Environmental Protection Agency (US EPA). Results of the risk assessment revealed that the magnitude and distribution of the chemicals at the site were such that extensive remediation was not required, and that the site could be developed without any significant restrictions on the proposed use. The assessment revealed that potential exposure to soil constituents would not result in adverse health risk to construction workers involved in park development or future park users.Napravljena je procjena zdravstvenoga rizika za ljude (izv. human health risk assessment, HHRA) za projekt gradskoga parka “River Landing” koji bi se trebao izgraditi duž sjeverne obale rijeke South Saskatchewan u Saskatoonu, saveznoj državi Saskatchewan u Kanadi. Svrha je procjene bila utvrditi mogu li kemijski spojevi zatečeni na gradilištu, uključujući policikličke aromatske ugljikovodike, naftne ugljikovodike te toksične i teške metale, štetno utjecati na zdravlje građevinskih radnika i korisnika parka. Premda je razmotrena i uporaba tradicionalnijih metoda sanacije, izabran je ovaj pristup procjeni rizika zbog toga što rabi najbolju dostupnu tehnologiju. Procjena rizika provedena je prema protokolima i metodama koje je odmah usvojio Kanadski savjet ministara za zaštitu okoliša (izv. Canadian Council of Ministers of the Environment, CCME), savezni ured za zdravlje Health Canada te Agencija za zaštitu okoliša Sjedinjenih Država (izv. United States Environmental Protection Agency, US EPA). Procjena rizika pokazala je da količina i rasprostranjenost kemikalija na gradilištu nisu takvi da zahtijevaju opsežniju sanaciju, te da se lokacija može izgraditi bez značajnih ograničenja u namjeni. Procjenom je također utvrđeno da eventualno izlaganje sastavnicama tla neće dovesti do štetnih posljedica za zdravlje građevinskih radnika koji rade na parku, a niti za buduće korisnike parka

    Globalization, multinationals and institutional diversity

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    This article aims to explore the impact of globalization and in particular multinationals on diversity within national varieties of capitalism. Do the actions of multinationals create more diversity within national systems, do they reduce diversity or do they have relatively little impact on diversity within national systems? The article argues that there are distinctive structures of institutional diversity across different national systems. Therefore, the question is not how do MNCs impact on institutional diversity per se but how do they impact on these different structures of diversity? In order to develop this argument, the paper also differentiates types of multinational. The article uses distinction between market-seeking, resource-seeking, efficiency-seeking and strategic asset-seeking in order to identify a range of different MNC activity across manufacturing, professional and financial sectors. These different sorts of MNC activity vary across time and contexts in terms of their significance. The article looks in detail at four different models of capitalism and examines how the entry of different sorts of multinationals with distinctive objectives impacts on the relationships between key social actors which underpin and reinforce these models. In this way, it suggests how institutional diversity within different types of capitalism may evolve under the impact of MNCs and globalization
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