Tree bark has proved to be a useful bioindicator for trace elements in the atmosphere, however it reflects an exposure occurring during an unidentified period of time, so it provides spatial information about the distribution of contaminants in a certain area, but it cannot be used to detect temporal changes or trends, which is an important achievement in environmental studies. In order to obtain information about a known period of time, the bark collected from the annual segments of tree branches can be used, allowing analyses going back 10-15 years with annual resolution. In the present study, the concentrations of As, Cd, Co, Cu, Fe, Mn, Ni, Pb, V and Zn were measured by atomic emission spectrometry in a series of samples covering the period from 2001 to 2013 in an urban environment. Downward time trends were significant for Cd, Pb and Zn. The only trace element showing an upward time trend was V. The concentrations of the remaining six trace elements were constant over time, showing that their presence in bark is not simply proportional to the duration of exposure. This approach, which is simple, reliable and widely applicable at a low cost, allows the "a posteriori" reconstruction of atmospheric trace element deposition when or where no monitoring programme is in progress and no other natural archives are available.
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http://dx.doi.org/10.1016/j.envres.2017.01.022 | DOI Listing |
Biotechnol Lett
January 2025
Extremophile and Productive Microorganisms Research Center, Kerman University of Medical Sciences, Kerman, Iran.
Selenium is an essential element with various industrial and medical applications, hence the current considerable attention towards the genesis and utilization of SeNPs. SeNPs and other nanoparticles could be achieved via physical and chemical methods, but these methods would not only require expensive equipment and specific reagents but are also not always environment friendly. Biogenesis of SeNPs could therefore be considered as a less troublesome alternative, which opens an excellent window to the selenium and nanoparticles' world.
View Article and Find Full Text PDFJ Orthop Surg Res
January 2025
Xuzhou Medical University Affiliated Stomatology Hospital, Xuzhou, 221002, Jiangsu Province, China.
Purpose: We aimed to explore the mechanism by which Boron-doped nano-hydroxyapatite (B-nHAp) facilitates the proliferation and differentiation of osteoblasts through controlled release of B.
Methods: B-nHAp characterization was accomplished by means of X-ray diffraction, scanning electron microscopy, inductively coupled plasma mass spectrometry, and transmission electron microscopy. Human bone marrow mesenchymal stem cells (hBMSCs) were subjected to flow cytometry, alizarin red S staining, and cell counting kit-8 assay for proliferation and differentiation determination.
Environ Geochem Health
January 2025
College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.
The superposition of heavy metals (HMs) from multiple anthropogenic sources in geochemical anomaly areas makes it difficult to discriminate prime sources in atmospheric HMs. This study utilized a combination of microscopic features, positive matrix factorisation, and Pb isotope fingerprints to trace the main sources of HMs bound to total suspended particulates (TSP) at a pollution site (Msoshui: MS) and control site (Lushan: LS) in northwestern Guizhou. The results reveal that the concentrations of Cd, Pb, Cr, As, Cu, Ni, and Zn in the TSP of LS are 3.
View Article and Find Full Text PDFSupport Care Cancer
January 2025
Department of Stomatology, Federal University of Paraná, Av. Prefeito Lothário Meissner, 632, 80210-170, Curitiba, PR, Brazil.
Objective: To evaluate the efficacy of photobiomodulation therapy (PBMT) and bethanechol chloride (BC) on the quantity and quality of saliva in patients undergoing radiotherapy (RT) for head and neck cancer.
Methods: Saliva samples were collected from patients before and after RT, who were treated with PBMT or BC. Clinical parameters, including salivary flow rate (SFR), pH, xerostomia, and concentrations of macro and microelements in saliva, were assessed.
Nat Commun
January 2025
Department of Biochemistry, University of Zurich, Zurich, Switzerland.
Iron and manganese are essential nutrients whose transport across membranes is catalyzed by members of the SLC11 family. In humans, this protein family contains two paralogs, the ubiquitously expressed DMT1, which is involved in the uptake and distribution of Fe and Mn, and NRAMP1, which participates in the resistance against infections and nutrient recycling. Despite previous studies contributing to our mechanistic understanding of the family, the structures of human SLC11 proteins and their relationship to functional properties have remained elusive.
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