Monitoring of immission of persistent organic pollutants in the industrialized area of Volta Redonda (V.R.) and in the National Park of Itatiaia (PNI) in southeast Brazil was performed using an endemic Bromeliad species as biomonitor and measuring total deposition rates on funnels covered with polyurethane foams. Samples were collected during 78 days in V.R. and 95 days in PNI in winter (dry season, June-August 2003) and during 114 days in both areas in summer (rainy season, December 2003-February 2004). The PCDD/PCDF deposition rates ranged from 0.10 to 1.9 pg WHO-TEQ/(m2 day) in winter and from 0.11 to 2.2 pg WHO-TEQ/(m2 day) in summer. Deposition rates found in V.R. in summer were four- to ninefold higher than those measured in PNI, while in winter deposition rates in both regions were in the same range. Deposition rates in V.R. in summer were about five fold lower than those measured in 1996. PCDD/PCDF levels in biomonitor samples were between 0.95 and 14.6 ng WHO-TEQ/kg d.m. in winter and between 2.2 and 5.2 ng WHO-TEQ/kg d.m. in summer. In winter, concentrations found in V.R. were up to 11 times higher than those found in PNI, while in summer the levels measured in both areas were comparable. The homologue and isomer profiles found in the deposition as well as in the biomonitor samples from V.R. indicate that steel production is the main source of contamination in the region, whereas in PNI, the long range transport of these pollutants is the predominant contamination pathway.
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http://dx.doi.org/10.1016/j.chemosphere.2006.05.145 | DOI Listing |
Cochrane Database Syst Rev
January 2025
Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
Background: Financial incentives (money, vouchers, or self-deposits) can be used to positively reinforce smoking cessation. They may be used as one-off rewards, or in various schedules to reward steps towards sustained smoking abstinence (known as contingency management). They have been used in workplaces, clinics, hospitals, and community settings, and to target particular populations.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Nanjing Institute of Environmental Sciences (NIES), Ministry of Ecology and Environment (MEE), Nanjing, 210042, China.
Terrestrial ecosystem carbon sinks are a natural deposit that absorbs carbon from the atmosphere. A stable land carbon sink facilitates more reliable predictions of carbon sequestration under changing climate conditions. In contrast, a highly variable land carbon sink will introduce significant uncertainty into model predictions.
View Article and Find Full Text PDFBiomater Adv
January 2025
College of Medical Technology and Engineering, Henan University of Science and Technology, Luoyang 471023, China.
Hydrogels possessing appropriate adhesion and antibacterial properties have emerged as promising dressings for expediting wound healing, while also providing the convenience of visualizing the wound site to accurately monitor the healing process. In this study, we incorporated oxidized and degraded polydopamine nanoparticles into quaternized chitosan/oxidized dextran hydrogel QOP series, resulting in enhanced transmittance exceeding 95 % and adhesion strengths reaching up to 19.4 kPa.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Suzhou Guardex New Material Technology Co., Ltd., Suzhou 210500, China.
Cementitious Capillary Crystallization Waterproofing Material (CCCW), as an efficient self-healing agent, can effectively repair damage in concrete structures, thereby extending their service life. To address the various types of damage encountered in practical engineering applications, this study investigates the impact of different mixing methods for CCCW (including internal mixing, curing, and post-crack repair) on the multi-dimensional self-healing performance of concrete. The self-healing capacity of concrete was evaluated through water pressure damage self-healing tests, freeze-thaw damage self-healing tests, mechanical load damage self-healing tests, and crack damage self-healing tests.
View Article and Find Full Text PDFMolecules
December 2024
Chair for Integrated Systems and Photonics, Department of Electrical and Information Engineering, Faculty of Engineering, Kiel University, Kaiserstr. 2, 24143 Kiel, Germany.
Biological neural circuits are based on the interplay of excitatory and inhibitory events to achieve functionality. Axons form long-range information highways in neural circuits. Axon pruning, i.
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