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At least 325 records · Page 18

Exposure to environment chemicals and its possible role in endocrine disruption of children from a rural area

Highlights: • Rural children had elevated blood and hair Mn and Cr levels. • Disruption on thyroid function can be related to metals exposure in rural areas. • Dyslipidemia is associated to thyroid dysfunction in children exposed to metals. • Cholinesterase inhibitors insecticides affect the glucose homeostasis of children. • Children exposed to high levels of Mn can be evaluated through the prolactin. Endocrine disrupting chemicals (EDCs), including pesticides and metals, are present in rural areas, endangering the health of exposed populations. This work aimed to investigate the possible association between the exposure to these xenobiotics and thyroid dysfunction in children living in a rural community of Southern Brazil. Fifty-four children aged 5–16 years participated in this study. Peripheral biomarker evaluations were performed in periods of low and high exposure to pesticides. Thyroid ultrasonography was evaluated in the high exposure period. Blood levels of chromium (Cr), manganese (Mn), mercury (Hg), and lead (Pb), as well as hair Pb levels were positively correlated with thyroid stimulating hormone (TSH) concentrations and negatively associated with free thyroxine (fT4) levels in the low exposure period. Prolactin was positively associated with hair Mn in both periods. In the ultrasound tests, the majority of children presented a normal echogenicity of thyroid. Glucose was inversely associated with the biomarker of exposure to cholinesterase inhibitor insecticides, butyrylcholinesterase (BuChE). Lipid profile was above the recommended levels in both periods. In summary, our results show that children environmentally exposed to a mixture of xenobiotics in an agricultural community may have health impairments, especially on thyroid function, dyslipidemia, and glucose homeostasis disruption.

54 ENVIRONMENTAL SCIENCES↗

Reverse logistics network for municipal solid waste management: The inclusion of waste pickers as a Brazilian legal requirement

Highlights: • We propose a reverse logistics network for MSW involving waste pickers. • A generic facility location mathematical model was validated in a Brazilian city. • The results enable to predict the capacity for screening and storage centres (SSC). • We minimise the costs for transporting MSW with screening and storage centres. • The use of SSC can be a potential source of revenue and a better use of MSW. - Abstract: This study proposes a reverse logistics network involved in the management of municipal solid waste (MSW) to solve the challenge of economically managing these wastes considering the recent legal requirements of the Brazilian Waste Management Policy. The feasibility of the allocation of MSW material recovery facilities (MRF) as intermediate points between the generators of these wastes and the options for reuse and disposal was evaluated, as well as the participation of associations and cooperatives of waste pickers. This network was mathematically modelled and validated through a scenario analysis of the municipality of São Mateus, which makes the location model more complete and applicable in practice. The mathematical model allows the determination of the number of facilities required for the reverse logistics network, their location, capacities, and product flows between these facilities. The fixed costs of installation and operation of the proposed MRF were balanced with the reduction of transport costs, allowing the inclusion of waste pickers to the reverse logistics network. The main contribution of this study lies in the proposition of a reverse logistics network for MSW simultaneously involving legal, environmental, economic and social criteria, which is a very complex goal. This study can guide practices in other countries that have realities similar to those in Brazil of accelerated urbanisation without adequate planning for solid waste management, added to the strong presence of waste pickers that, through the characteristic of social vulnerability, must be included in the system. In addition to the theoretical contribution to the reverse logistics network problem, this study aids in decision-making for public managers who have limited technical and administrative capacities for the management of solid wastes.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Higher‐Order Gravity Waves and Traveling Ionospheric Disturbances From the Polar Vortex Jet on 11–15 January 2016: Modeling With HIAMCM‐SAMI3 and Comparison With Observations in the Thermosphere and Ionosphere

Abstract In Vadas et al. (2024, https://doi.org/10.1029/2024ja032521 ), we modeled the atmospheric gravity waves (GWs) during 11–14 January 2016 using the HIAMCM, and found that the polar vortex jet generates medium to large‐scale, higher‐order GWs in the thermosphere. In this paper, we model the traveling ionospheric disturbances (TIDs) generated by these GWs using the HIAMCM‐SAMI3 and compare with ionospheric observations from ground‐based Global Navigation Satellite System (GNSS) receivers, Incoherent Scatter Radars (ISR) and the Super Dual Auroral Radar Network (SuperDARN). We find that medium to large‐scale TIDs are generated worldwide by the higher‐order GWs from this event. Many of the TIDs over Europe and Asia have concentric ring/arc‐like structure, and most of those over North/South America have planar wave structure and occur during the daytime. Those over North/South America propagate southward and are generated by higher‐order GWs from Europe/Asia which propagate over the Arctic. These latter TIDs can be misidentified as arising from geomagnetic forcing. We find that the higher‐order GWs that propagate to Africa and Brazil from Europe may aid in the formation of equatorial plasma bubbles (EPBs) there. We find that the simulated GWs, TIDs and EPBs agree with EISCAT, PFISR, GNSS, and SuperDARN measurements. We find that the higher‐order GWs are concentrated at N at 200 km, in agreement with GOCE and CHAMP data. Thus the polar vortex jet is important for generating TIDs in the northern winter ionosphere via multi‐step vertical coupling through GWs.

Vadas, Sharon L. [Northwest Research Associates Bo↗

Improving Resilience of Bus Bunching Holding Strategy through a Rolling Horizon Approach

Providing public transportation with quality service is critical to attracting more passengers to the system. However, high-demand routes are prone to the so-called bus bunching -- a tendency of buses to group as a consequence of variations in travel times and demands. Bus holding is applied to overcome this effect. In this study, we present a novel method for bus holding in which the control law is based only on the buses' position using a computationally efficient rolling horizon approach. The method uses similar inputs as linear control approaches while not increasing significantly the computational time. However, the method overcomes key a weakness of the linear control approach thanks to the explicit constraint handling that always ensures the control action effectiveness. Simulation experiments in a validation case and a model-specific for a bus rapid transit line in Curitiba, Brazil showed a reduced holding time and improved resilience, delivering more than 20% reduction in delay time accounting for the on-board and station delays.

33 ADVANCED PROPULSION SYSTEMS↗

An integrated model supporting histological and biometric responses as predictive biomarkers of fish health status

In this work, an experimental system of histological (branchial lesions) biomarkers and biometric data in catfish (Sciades herzbergii) was modeled. The fish were sampled along known pollution areas (S1) and from environmental protect areas (S2) in São Marcos' Bay, Brazil. Gills were fixed in 10% formalin and usual histological techniques were used in the first gill arch right. The lesions were observed by light microscopy. There were no histopathological changes in animals captured at reference site (S1). However, in the catfish collected in the potentially contaminated area (S2) was observed several branchial lesions, such as lifting of the lamellar epithelium, fusion of some secondary lamellae, hypertrophy of epithelial cells and lamellar aneurysm. The analysis using the biometric data showed significant differences, being highest in fish analyzed in the reference area. This approach revealed spatial differences related with biometric patterns and morphological modifications of catfish.

60 APPLIED LIFE SCIENCES↗

Telescope performance and image simulations of the balloon-borne coded-mask protoMIRAX experiment

In this work we present the results of imaging simulations performed with the help of the GEANT4 package for the protoMIRAX hard X-ray balloon experiment. The instrumental background was simulated taking into account the various radiation components and their angular dependence, as well as a detailed mass model of the experiment. We modelled the meridian transits of the Crab Nebula and the Galactic Centre (CG) region during balloon flights in Brazil (∼ −23° of latitude and an altitude of ∼40 km) and introduced the correspondent spectra as inputs to the imaging simulations. We present images of the Crab and of three sources in the GC: 1E 1740.7-2942, GRS 1758-258 and GX 1+4. The results show that the protoMIRAX experiment is capable of making spectral and timing observations of bright hard X-ray sources as well as important imaging demonstrations that will contribute to the design of the MIRAX satellite mission.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Contribution of the conferences of the parties and the renewable energy role for the fight against climate change

The Kyoto Protocol, which entered into force on 16 February 2005, commits developed countries to reduce their emissions of greenhouse gases by 5% in 2012 compared to 1990. Due to the abstention of the United States and the absence of constraint on Southern countries, the protocol establishes obligations only to countries that represent only 33% of global CO{sub 2} emissions. All the diplomatic effort is therefore to seek the commitment of discussion for the period after 2012. The participation of the United States and emerging countries is imperative. The essential point of this second negotiation process is to search in the effort to integrate the United States and the developing countries and, more particularly, emerging economies such as China, India or Brazil, whose current emissions and / or projected should exceed those of developed countries during the first half of the twenty-first century. Real progress has been made in recent years. Indeed, a first universal historic agreement and legally binding was adopted after two weeks of intense negotiations by the Parties from 30 November to 12 December 2015, which aims to limit global warming by the end of this century well below 2 ° C while continuing efforts to not exceed 1.5 ° C. Moreover, the European Union, China and the United States have expressed their willingness to reduce their greenhouse gas. Because, one of the great hopes of the fight against the emission of greenhouse gases is the development of renewable energy, the IPCC (Intergovernmental Panel on Climate Change) report highlights the need to move towards renewable energy sources. The European Union, China and United States also expressed their willingness to increase the share of renewable energy. It is therefore necessary to develop the only inexhaustible energy, renewable energy, to fight against climate change.

54 ENVIRONMENTAL SCIENCES↗

Thermal Performance Analysis of a Geologic Borehole Repository

The Brazilian Nuclear Research Institute (IPEN) proposed a design for the disposal of Disused Sealed Radioactive Sources (DSRS) based on the IAEA Borehole Disposal of Sealed Radioactive Sources (BOSS) design that would allow the entirety of Brazil’s inventory of DSRS to be disposed in a single borehole. The proposed IPEN design allows for 170 waste packages (WPs) containing DSRS (such as Co-60 and Cs-137) to be stacked on top of each other inside the borehole. The primary objective of this work was to evaluate the thermal performance of a conservative approach to the IPEN proposal with the equivalent of two WPs and two different inside configurations using Co-60 as the radioactive heat source. The current WP configuration (heterogeneous) for the IPEN proposal has 60% of the WP volume being occupied by a nuclear radioactive heat source and the remaining 40% as vacant space. The second configuration (homogeneous) considered for this project was a homogeneous case where 100% of the WP volume was occupied by a nuclear radioactive heat source. The computational models for the thermal analyses of the WP configurations with the Co-60 heat source considered three different cooling mechanisms (conduction, radiation, and convection) and the effect of mesh size on the results from the thermal analysis. The results of the analyses yielded maximum temperatures inside the WPs for both of the WP configurations and various mesh sizes. The heterogeneous WP considered the cooling mechanisms of conduction, convection, and radiation. The temperature results from the heterogeneous WP analysis suggest that the model is cooled predominantly by conduction with effect of radiation and natural convection on cooling being negligible. From the thermal analysis comparing the two WP configurations, the results suggest that either WP configuration could be used for the design. The mesh sensitivity results verify the meshes used, and results obtained from the thermal analyses were close to being independent of mesh size. The results from the computational case and analytically-calculated case for the homogeneous WP in benchmarking were almost identical, which indicates that the computational approach used here was successfully verified by the analytical solution.

07 ISOTOPE AND RADIATION SOURCES↗

Green Ocean Amazon 2014/15 Manaus Pollution Study Field Campaign Report

This work was part of the larger Green Ocean Amazon 2014/15 (GOAmazon 2014/15) experiment, which extended through the wet and dry seasons from January 2014 through December 2015 and which took place around the urban region of Manaus, Brazil in central Amazonia. This work was conducted as part of this experiment at the main U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility ground research site “T3” circa 100 km west of Manaus during two intensive operational periods, “IOP1” and “IOP2” (February 1 to March 31, 2014, and August 15 to October 15, 2014, respectively). Funding for this work was provided by the National Science Foundation AGS 1321987/1628491. The GoAmazon experiment was designed to enable the study of how aerosols and surface fluxes influence cloud cycles under clean conditions, as well as how aerosol and cloud life cycles, including cloud-aerosol-precipitation interactions, are influenced by pollutant outflow from a tropical megacity. These observations provide a data set vital to constrain tropical rain forest model parameterizations for organic aerosols, cloud and convection schemes, and terrestrial vegetation components and how these are perturbed by pollution. Research objectives specific to this work and the T3 ground site included studies of how outflow of pollution from Manaus modulated the photochemically driven conversion of emitted precursors to aerosol precursors and aerosol.

54 ENVIRONMENTAL SCIENCES↗

Shell structure and distribution of Cloudina, a potential index fossil for the terminal Proterozoic

Cloudina-bearing biosparites and biomicrites in the lower part of the Nama Group, Namibia, contain a wide morphological diversity of shell fragments that can all be attributed to the two named species C. hartmannae and C. riemkeae. The curved to sinuous tubular shells of Cloudina were multi-layered. Each shell layer was 8 to 50 micrometers thick and in the form of a slightly flaring tube with one end open and the other closed. Growth appears to have been periodic with successive shell layers forming within older layers. Each added layer was slightly elevated from the previous layer at the proximal end and was asymmetrically placed within the older layer so that only a portion of the new shell layer was fused to the previous layer. This type of growth left a relatively large unminerialized area between the shell layers which was often partially or fully occluded by early marine cements. The thin shell layers exhibit both plastic and brittle deformation and were likely formed of a rigid CaCO3-impregnated organic-rich material. Often the shell layers are preferentially dolomitized suggesting an original mineralogy of high-magnesian calcite. Both species in the Nama Group formed thickets, or perhaps bioherms, and this sedentary and gregarious habit suggests that Cloudina was probably a filter-feeding metazoan of at least a cnidarian grade of organization. The unusual shell structure of Cloudina gives rise to a characteristic suite of taphonomic and diagenetic features that can be used to identify Cloudina-bearing deposits within the Nama Group and in other terminal Proterozoic deposits around the world. Species of Cloudina occur in limestones from Brazil, Spain, China, and Oman in sequences consistent with a latest Proterozoic age assignment. In addition, supposed lower Cambrian, pre-trilobitic, shelly fossils from northwest Mexico and the White-Inyo Mountains in California and Nevada, including Sinotubulites, Nevadatubulus, and Wyattia, are all either closely related to or con-generic with Cloudina. Hence, it is probable that these outcrops are latest Proterozoic in age, and that Cloudina or Cloudina-like organisms were widely distributed at that time. It is possible, moreover, to suggest that metazoan biomineralization occurred on a global scale by the latest Proterozoic, at the same time that evidence for complex multicellularity and locomotion in animals appears in siliciclastic "Ediacaran" rocks in the form of body and trace fossils.

NASA Program Exobiology↗

Options for Resilient and Flexible Power Systems in Select South American Economies

This document is the executive summary for the technical report titled 'Options for Resilient and Flexible Power Systems in Select South American Economies' that summarizes opportunities for Argentina, Brazil, Chile and Colombia to adapt to the new forces buffeting electricity sectors around the globe to ensure reliable, affordable, sustainable and resilient power systems. Special attention is placed on the potential role for natural gas to help ensure flexible and resilient power.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Options for Resilient and Flexible Power Systems in Select South American Economies

This presentation provides highlights from the published report NREL/TP-6A50-75431, which summarizes opportunities for Argentina, Brazil, Chile and Colombia to adapt to the new forces buffeting electricity sectors around the globe to ensure reliable, affordable, sustainable and resilient power systems. Special attention is placed on the potential role for natural gas to help ensure flexible and resilient power.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Management of Ir-192 Disused Sealed Sources with Long-Lived Radioactive Contaminants

Iridium-192 sealed sources are the most widely used sealed source in industrial applications in Brazil. They are not recyclable and in the end of the useful life, they are discarded as radioactive waste. The recommended management strategy of this waste is decay in storage and disposal as exempt waste because the half-life is only 73.8 days. Presently, thousands of Ir- 192 sources are under storage waiting release. Surprisingly, sources that were under storage for more than ten years and for which no measurable contact dose rate was expected still present significant remaining radioactivity. The examination of the gamma spectra of these sources showed the presence of Co-60 and the gamma emission lines from the Ir-192m2 isomer, the metastable isotope with half-life of 241 years, which is also formed by the irradiation of natural iridium. The aim of the study reported in this paper is to characterize the Ir-192 disused sources under interim storage at the Radioactive Waste Management Department, considering the presence of minor contaminants in the irradiated iridium and the fraction of the total initial activity of the sources that is attributable to that metastable isotope. The radioactive inventories at the end of the irradiation and after the decay period were predicted using the Scale 6.0 code and the results were compared with activity measurements of the disused sources by gamma spectrometry. (authors)

07 ISOTOPE AND RADIATION SOURCES↗

Strategic Planning as a Competitive Advantage by Using the BSC as a Management Tool: a Case Study in Application of Radioisotope Technology at IPEN - 16400

Strategic planning is one of the most important management tools for organizational decision making. The nuclear area represents a segment of energy production used by many countries in America, Europe and Asia. It is known that in the future nuclear energy can be a major exit to the global energy crisis. The aim of this research was to use the Balanced Scorecard (BSC) as a strategic tool for decision making in a teaching and research institution of the nuclear area - Nuclear and Energy Research Institute (IPEN), located in the city of Sao Paulo, which belongs to the National Nuclear Energy Commission (CNEN) in Brazil. The methodology used in this academic doctoral study was a case study, which considered the period of research from December 2012 to December 2015. The main results expected from this case study are: the improvement of information flow, the view, the increased visibility of an organization providing education and especially research in relation to published works, increased interaction among IPEN and the main global research institutes and centers, increasing academic production of technical articles, indicator improvement, improving the monitoring of management actions, among others. Given the expected results one can conclude that this study will be of great value to the IPEN and also for the Brazilian energy sector, as it will allow and contribute to the dissemination and demystification of nuclear power as an energy source of mankind, its peaceful applications and for the management activity of knowledge and innovation production in the nuclear area of IPEN. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Constructing Memory Through Artistic Practices - 18197

I have been investigating radioactive waste sites internationally since 1994, analyzing how this archaeological stratum of the 21. century can be read in the landscape. Over more than twenty years of work this research has led me to visit several sites around the world. My focus has become the identification of the disposal sites in the landscape, as well as finding ways to pass on memory. Reports on Disposal Sites and Exhibitions: - Dessel, Belgium - exhibition at De Markten, Brussels; - Sacavem, Portugal - participation to the World Exhibition in Lisbon; - El Cabril, Spain - workshop at the University of Bilbao; - Angra dos Reis, Brazil - exhibition at Centre cultural Puc, Rio de Janeiro; - Rokkasho Mura, Japan - exhibition at gallery Gen, Tokyo; - Soulaines D'Huys, France - exhibition at art gallery Cours Carree, Paris; - CSM, Beaumont-Hague, France - exhibition at the House of Culture in Tournai, Belgium; - Fortsmark, Sweden - exhibition at 340 Muzeum, Brussels; - Cnesten Maamora, Morocco - exhibition at Villa des Arts, Casablanca; - Bhabha Atomic Research, Trombay, India - I was allowed to visit it but it was forbidden to make photographs or drawings. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Overview of IAEA MODARIA II Program Working Group 1 on Assessment and Decision Making of Existing Exposure Situations for NORM and Nuclear Legacy Sites - 18308

The International Atomic Energy Agency (IAEA) launched the Modelling and Data for Radiological Impact Assessments (MODARIA) II Programme in October. As part of the IAEA effort to enhance the capabilities of its Member States in assessing radiological impacts of radionuclides released to the environment from sites that were not operated in accordance with current standards, and to ensure protection of the public and the environment, the MODARIA II Programme aims to: (1) test the performance of models developed for predicting the transfer of radionuclides in the environment and assessing radiological impacts to the public and the environment; (2) develop and improve models for particular environments and, where appropriate, to agree on data sets that are generally applicable for use in testing environmental transfer models; and (3) provide an international forum for the exchange of experiences, ideas and research information. The Programme will run for 3 years from 2016 to 2019. The Programme comprises seven working groups covering a wide range of topics (https://wwwns.iaea.org/projects/modaria/modaria2.asp?s=8 and l=129). MODARIA II Working Group 1 (WG1) is focused on dose assessment and decision making regarding existing exposure situations due to naturally occurring radioactive material (NORM) and nuclear legacy sites. WG1 was formed as a combination of two MODARIA I WGs: WG1 focused on application of decision-aiding tools in remediation; and WG3 focused on risk assessment for NORM and radioactively contaminated legacy sites (https://wwwns.iaea.org/projects/modaria/default.asp?s=8 and l=129). It was recognized that the decision-making needs will inform the scope of risk assessments, and the risk insights and structured decision analyses will aid in informed decision-making. Therefore, MODARIA II WG1 is focused on developing methods and toolsets for risk-informed decision-making for NORM and nuclear legacy sites, including demonstration of decision-making processes and tools through case studies. MODARIA II WG1 has 91 registered participants from 33 Member States and IAEA (as of November 2017), some 30 of whom are actively engaged in various collaborative research and development activities within WG1. Members of WG1 participated in the First Technical Meeting of MODARIA II, which was held in Vienna, Austria from 31 October to 4 November 2016. The group then held its First Interim Meeting in Brussels, Belgium from 26 to 30 June 2017, which included a field trip to the legacy Tessenderlo Chemie (TCH) Phosphate Processing Site. At this meeting, the TCH Site and the Pridneprovsky Chemical Plant (PChP) in Ukraine were selected for case studies. The Los Alamos National Laboratory (LANL) Material Disposal Area B in the USA and the Beaverlodge Uranium Mill and Mill Site in northern Canada were selected as examples for sharing of good practices and lessons learned in risk-informed decision-making for environmental remediation and land conveyance. At the Second Technical Meeting held in Vienna on 30 October to 3 November 2017, an additional NORM site for tin processing in Brazil was added to the case studies, with another NORM site in Yunnan, China included for consideration at the Second Interim Meeting of WG1. The Second Interim Meeting will be held in in early to mid-May, 2018. The group has also decided to prepare an Interim Report by October 2018 to document the WG1 discussions and analyses for the period of 2016-2018, which will be finalized at the conclusion of MODARIA II in October 2019. Initial assignments have been discussed for IM1 participants to collect data, conduct modelling and analyses, and prepare draft sections for the Interim Report. This paper will provide an overview of the work plans for WG1. It will also highlight some near-term activities that the group is currently working on. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗