scholarly journals Human body burdens of chemicals used in plastic manufacture

2009 ◽  
Vol 364 (1526) ◽  
pp. 2063-2078 ◽  
Author(s):  
Holger M. Koch ◽  
Antonia M. Calafat

In the last decades, the availability of sophisticated analytical chemistry techniques has facilitated measuring trace levels of multiple environmental chemicals in human biological matrices (i.e. biomonitoring) with a high degree of accuracy and precision. As biomonitoring data have become readily available, interest in their interpretation has increased. We present an overview on the use of biomonitoring in exposure and risk assessment using phthalates and bisphenol A as examples of chemicals used in the manufacture of plastic goods. We present and review the most relevant research on biomarkers of exposure for phthalates and bisphenol A, including novel and most comprehensive biomonitoring data from Germany and the United States. We discuss several factors relevant for interpreting and understanding biomonitoring data, including selection of both biomarkers of exposure and human matrices, and toxicokinetic information.

Endocrinology ◽  
2005 ◽  
Vol 146 (2) ◽  
pp. 607-612 ◽  
Author(s):  
R. Thomas Zoeller ◽  
Ruby Bansal ◽  
Colleen Parris

Abstract Considering the importance of thyroid hormone (TH) in brain development, it is of potential concern that a wide variety of environmental chemicals can interfere with thyroid function or, perhaps of greater concern, with TH action at its receptor (TR). Recently bisphenol-A (BPA, 4,4′ isopropylidenediphenol) was reported to bind to the rat TR and act as an antagonist in vitro. BPA is a high production volume chemical, with more than 800 million kg of BPA produced annually in the United States alone. It is detectable in serum of pregnant women and cord serum taken at birth; is 5-fold higher in amniotic fluid at 15–18 wk gestation, compared with maternal serum; and was found in concentrations of up to 100 ng/g in placenta. Thus, the human population is widely exposed to BPA and it appears to accumulate in the fetus. We now report that dietary exposure to BPA of Sprague Dawley rats during pregnancy and lactation causes an increase in serum total T4 in pups on postnatal d 15, but serum TSH was not different from controls. The expression of the TH-responsive gene RC3/neurogranin, measured by in situ hybridization, was significantly up-regulated by BPA in the dentate gyrus. These findings suggest that BPA acts as a TH antagonist on the β-TR, which mediates the negative feedback effect of TH on the pituitary gland, but that BPA is less effective at antagonizing TH on the α-TR, leaving TRα-mediated events to respond to elevated T4.


Author(s):  
Manish M. Kayasth ◽  
Bharat C. Patel

The entire character recognition system is logically characterized into different sections like Scanning, Pre-processing, Classification, Processing, and Post-processing. In the targeted system, the scanned image is first passed through pre-processing modules then feature extraction, classification in order to achieve a high recognition rate. This paper describes mainly on Feature extraction and Classification technique. These are the methodologies which play an important role to identify offline handwritten characters specifically in Gujarati language. Feature extraction provides methods with the help of which characters can identify uniquely and with high degree of accuracy. Feature extraction helps to find the shape contained in the pattern. Several techniques are available for feature extraction and classification, however the selection of an appropriate technique based on its input decides the degree of accuracy of recognition. 


This collection examines the phenomenon of the operatic canon: its formation, history, current ontology and practical influence, and future. It does so by taking an international and interdisciplinary view: the workshops from which it was derived included the participation of critics, producers, artistic directors, stage directors, opera company CEOs, and even economists, from the United Kingdom, the United States, France, Italy, Ireland, Germany, the Netherlands, Denmark, and Canada. The volume is structured as a series of dialogues: each subtopic is addressed by two essays, introduced jointly by the authors, and followed by a jointly compiled list of further reading. These paired essays complement each other in different ways, for example by treating the same geographical location in different periods, by providing different national or regional perspectives on the same period, or by thinking through similar conceptual issues in contrasting milieus. Part I consists of a selection of surveys of operatic production and consumption contexts in France, Italy, Germany, England, Russia, and the Americas, arranged in rough order from the late seventeenth century to the late nineteenth century. Part II is a (necessarily) limited sample of subjects that illuminate the operatic canon from different—sometimes intentionally oblique—angles, ranging from the influence of singers to the contiguous genres of operetta and musical theater, and the effects of recording and broadcast over almost 150 years. The volume concludes with two essays written by prominent figures from the opera industry who give their sense of the operatic canon’s evolution and prospects.


2021 ◽  
pp. 1-16
Author(s):  
Hajer Al-Faham

How does surveillance shape political science research in the United States? In comparative and international politics, there is a rich literature concerning the conduct of research amid conditions of conflict and state repression. As this literature locates “the field” in distant contexts “over there,” the United States continues to be saturated with various forms of state control. What this portends for American politics research has thus far been examined by a limited selection of scholars. Expanding on their insights, I situate “the field” in the United States and examine surveillance of American Muslims, an understudied case of racialized state control. Drawing on qualitative data from a case study of sixty-nine interviews with Arab and Black American Muslims, I argue that surveillance operated as a two-stage political mechanism that mapped onto research methodologically and substantively. In the first stage, surveillance reconfigured the researcher-researchee dynamic, hindered recruitment and access, and limited data-collection. In the second stage, surveillance colored the self-perceptions, political attitudes, and civic engagement of respondents, thereby indicating a political socialization unfolding among Muslims. The implications of this study suggest that researchers can mitigate against some, but not all, of the challenges presented by surveillance and concomitant forms of state control.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Diksha Sirohi ◽  
Ruqaiya Al Ramadhani ◽  
Luke D. Knibbs

AbstractPurposeEndocrine-related diseases and disorders are on the rise globally. Synthetically produced environmental chemicals (endocrine-disrupting chemicals (EDCs)) mimic hormones like oestrogen and alter signalling pathways. Endometriosis is an oestrogen-dependent condition, affecting 10–15% of women of the reproductive age, and has substantial impacts on the quality of life. The aetiology of endometriosis is believed to be multifactorial, ranging from genetic causes to immunologic dysfunction due to environmental exposure to EDCs. Hence, we undertook a systematic review and investigated the epidemiological evidence for an association between EDCs and the development of endometriosis. We also aimed to assess studies on the relationship between body concentration of EDCs and the severity of endometriosis.MethodFollowing PRISMA guidelines, a structured search of PubMed, Embase and Scopus was conducted (to July 2018). The included studies analysed the association between one or more EDCs and the prevalence of endometriosis. The types of EDCs, association and outcome, participant characteristics and confounding variables were extracted and analysed. Quality assessment was performed using standard criteria.ResultsIn total, 29 studies were included. Phthalate esters were positively associated with the prevalence of endometriosis. The majority (71%) of studies revealed a significant association between bisphenol A, organochlorinated environmental pollutants (dioxins, dioxin-like compounds, organochlorinated pesticides, polychlorinated biphenyls) and the prevalence of endometriosis. A positive association between copper, chromium and prevalence of endometriosis was demonstrated in one study only. Cadmium, lead and mercury were not associated with the prevalence of endometriosis. There were conflicting results for the association between nickel and endometriosis. The relationship of EDCs and severity of endometriosis was not established in the studies.ConclusionWe found some evidence to suggest an association between phthalate esters, bisphenol A, organochlorinated environmental pollutants and the prevalence of endometriosis. Disentangling these exposures from various other factors that affect endometriosis is complex, but an important topic for further research.


Author(s):  
Behnam Jahangiri ◽  
Punyaslok Rath ◽  
Hamed Majidifard ◽  
William G. Buttlar

Various agencies have begun to research and introduce performance-related specifications (PRS) for the design of modern asphalt paving mixtures. The focus of most recent studies has been directed toward simplified cracking test development and evaluation. In some cases, development and validation of PRS has been performed, building on these new tests, often by comparison of test values to accelerated pavement test studies and/or to limited field data. This study describes the findings of a comprehensive research project conducted at Illinois Tollway, leading to a PRS for the design of mainline and shoulder asphalt mixtures. A novel approach was developed, involving the systematic establishment of specification requirements based on: 1) selection of baseline values based on minimally acceptable field performance thresholds; 2) elevation of thresholds to account for differences between short-term lab aging and expected long-term field aging; 3) further elevation of thresholds to account for variability in lab testing, plus variability in the testing of field cores; and 4) final adjustment and rounding of thresholds based on a consensus process. After a thorough evaluation of different candidate cracking tests in the course of the project, the Disk-shaped Compact Tension—DC(T)—test was chosen to be retained in the Illinois Tollway PRS and to be presented in this study for the design of crack-resistant mixtures. The DC(T) test was selected because of its high degree of correlation with field results and its excellent repeatability. Tailored Hamburg rut depth and stripping inflection point thresholds were also established for mainline and shoulder mixes.


2021 ◽  
Vol 5 ◽  
pp. 239920262110056
Author(s):  
John B Hertig ◽  
Shannon M James ◽  
Connor J Hummel ◽  
Matthew J Rubin

Background: An estimated 95% of all online pharmacies operate unlawfully. Illegal online pharmacies distribute substandard and falsified medical products that may result in patient harm and suboptimal treatment, leading to an overall mistrust of medications, healthcare providers, and health systems. As medication experts, pharmacists are trusted to guide patients in selection of safe and effective medication therapy. Objective: The objective of this study was to determine gaps in knowledge and recognition of the negative clinical and safety impacts associated with illegal Internet pharmacies by licensed pharmacists. Methods: A 37-question electronic survey was developed and distributed to pharmacists across the United States by email via a database from the American Pharmacists Association. Descriptive statistics was utilized to analyze data. Results: A total of 347 pharmacists from across the United States responded to at least one question in the survey. In all, 58% of pharmacists reported a lack of confidence in their ability to counsel patients on the identification of illegal pharmacy websites. Fewer than 60% of pharmacists were able to accurately identify the legitimacy of a webpage based on visual characteristics. In addition, 75% of pharmacists reported being unfamiliar with resources available to help consumers identify safe and legitimate online pharmacies. Conclusion: Integration of the topic into pharmacy education curricula, training on available resources, and additional research into the prevalence and impact of illegal pharmacy websites are necessary to ensure that pharmacists and other healthcare professionals are adequately prepared to protect their communities from the threat of illegal online pharmacies.


2021 ◽  
Vol 54 (3) ◽  
pp. 1-36
Author(s):  
Syed Wasif Abbas Hamdani ◽  
Haider Abbas ◽  
Abdul Rehman Janjua ◽  
Waleed Bin Shahid ◽  
Muhammad Faisal Amjad ◽  
...  

Cyber threats have been growing tremendously in recent years. There are significant advancements in the threat space that have led towards an essential need for the strengthening of digital infrastructure security. Better security can be achieved by fine-tuning system parameters to the best and optimized security levels. For the protection of infrastructure and information systems, several guidelines have been provided by well-known organizations in the form of cybersecurity standards. Since security vulnerabilities incur a very high degree of financial, reputational, informational, and organizational security compromise, it is imperative that a baseline for standard compliance be established. The selection of security standards and extracting requirements from those standards in an organizational context is a tedious task. This article presents a detailed literature review, a comprehensive analysis of various cybersecurity standards, and statistics of cyber-attacks related to operating systems (OS). In addition to that, an explicit comparison between the frameworks, tools, and software available for OS compliance testing is provided. An in-depth analysis of the most common software solutions ensuring compliance with certain cybersecurity standards is also presented. Finally, based on the cybersecurity standards under consideration, a comprehensive set of minimum requirements is proposed for OS hardening and a few open research challenges are discussed.


1971 ◽  
Vol 8 (3) ◽  
pp. 340-347 ◽  
Author(s):  
George S. Day ◽  
Roger M. Heeler

When the selection of a sample of stores or cities requires a high degree of similarity among the test units in order to ensure a sensitive experiment, the sample may no longer represent the market. These conflicting requirements can be satisfied by choosing the sample from clusters displayed in a reduced space representation of the market.


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