In order to better understand the bioavailability, toxicity, migration and transformation behaviors of trace metals in river estuary, this study deeply investigated the interactions between organic matters in sediments and trace metals. The results suggested that both protein-like molecules and marine humic acids could react with trace metals (Cu and Cd). These two fluorescent substances fixed trace metals through carboxyl group, hydroxyl group, and phenol hydroxyl group, and protein-like molecules were more sensitive than marine humic acids. Moreover, Cu possessed stronger binding ability and more active sites with both protein-like molecules and marine humic acids. Hence, Cd exhibited higher environmental risks due to the higher migration and transformation. The thermodynamic results revealed that the reaction between WEOM and trace metals was spontaneous and exothermic, and low temperature was favorable for immobilization of Cu or Cd.This study could help to understand environmental behaviors and impact of trace metals on the sediments of Yangtze River estuary.
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http://dx.doi.org/10.1016/j.saa.2022.121041 | DOI Listing |
Biol Trace Elem Res
January 2025
College of Arts & Sciences, American University of Kuwait, P.O. Box 3323, 13034, Safat, Kuwait.
Infants are particularly vulnerable to exposure to toxic trace elements due to their developmental stage and behaviors such as mouthing and chewing on toys. Chemical exposure to heavy metals in infants' toys is a significant concern as it poses a threat to their health and well-being. Therefore, quality control measures are essential to prevent infants' exposure to potentially harmful metals.
View Article and Find Full Text PDFPeerJ
January 2025
Florida Museum of Natural History, University of Florida, Gainesville, FL, United States of America.
The mechanisms that regulate minor and trace element biomineralization in the echinoid skeleton can be primarily controlled biologically (, by the organism and its vital effects) or by extrinsic environmental factors. Assessing the relative role of those controls is essential for understanding echinoid biomineralization, taphonomy, diagenesis, and their potential as geochemical archives. In this study, we (1) contrast geochemical signatures of specimens collected across multiple taxa and environmental settings to assess the effects of environmental and physiological factors on skeletal biomineralogy; and (2) analyze the nanomechanical properties of the echinoid skeleton to assess potential linkages between magnesium/calcium (Mg/Ca) ratios and skeletal nanohardness.
View Article and Find Full Text PDFMetal-organic framework materials exhibit significant potential for diverse applications in gas adsorption and separation. We have studied the performance changes of Cu-BTC, Cu-MBTC and Cu-EBTC under different water-containing conditions. GCMC studies shows that, compared with Cu-BTC, the water absorption properties of Cu-MBTC and Cu-EBTC have a certain degree of decline, which is consistent with the experimental results.
View Article and Find Full Text PDFMicrosc Res Tech
January 2025
Faculty of Dental Medicine, Grigore T. Popa University of Medicine and Pharmacy, Iasi, Romania.
One area of technological advancement has been the shift from stainless steel hand tools to nickel-titanium (Ni-Ti) rotary tools. This paper aims to perform an in vitro comparative study to evaluate the efficacy of five endodontic manual and rotary instruments such as Kerr files, Orodeka Plex V, ProTaper Flydent NiTi super files, and ProTaper Flydent NiTi super files in combination with an ultrasonic endodontic E3D Diamantata EMS scaler used for root canal shaping. The following aspects were highlighted: effective removal of smear layer (SL) from the dentinal tubules in the coronal 1/3, middle 1/3, and apical 1/3 of the root canal, appearance of cracks in the dentinal walls by SEM analysis, and highlighting of dentin mineral content and remnant debris by EDX analysis.
View Article and Find Full Text PDFBioelectrochemistry
January 2025
School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China; Laboratory for Clinical Medicine, Capital Medical University, Beijing 100069, China. Electronic address:
A ratiometric electrochemical aptasensor was developed for ultra-sensitive detection of cortisol using aptamer (Apt) as recognition element, methylene blue (MB) as signal probe, and zirconium metal-organic framework (Zr-MOF) as carrier loaded with abundant MB for signal amplification. The carboxylated multi-walled carbon nanotubes (cMWCNTs)-modified Au electrode showed excellent electrochemical performance to immobilize complementary DNA (cDNA) for hybridizing with MB@Zr-MOF-Apt via amide bonds. In the presence of cortisol, it would compete with cDNA for binding the Apt, resulting in the detachment of MB@Zr-MOF-Apt complex from the electrode surface, and the electrochemical signal of MB was decreased, while that of [Fe(CN)] was basically unchanged.
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