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1.
J Hazard Mater ; 479: 135706, 2024 Sep 02.
Article de Anglais | MEDLINE | ID: mdl-39241358

RÉSUMÉ

Studying the changes in organic matter and characteristic pollutants during the treatment of penicillin-containing pharmaceutical wastewater, which can be reflected by changes in dissolved organic matter (DOM), is crucial for improving the effectiveness of wastewater treatment units and systems. Herein, water quality indicators, spectroscopic methods, and Fourier-transform ion cyclotron resonance mass spectrometry were utilized to characterize the general molecular compositions and specific molecular changes in DOM during the treatment of typical penicillin-containing pharmaceutical wastewater, including in each of the influent, physicochemical treatment, biological treatment, oxidation treatment, and effluent stages. The influent exhibited a high organic matter content (concentration of dissolved organic carbon >10,000 mg·L-1), its DOM mainly contained protein- and lignin-like substances composed of CHON and CHONS molecules, and the relative intensity (RI) of penicillin was extremely high (RI = 0.220). Compared with the influent, the abundance of CHON and CHONS molecules detected after physicochemical treatment decreased by 70.3 % and 62.5 %, respectively, and the RI of penicillin decreased by 85.5 %. Biological treatment caused substantial changes in DOM components through oxidation, dealkylation, and denitrification reactions, accounting for 36.8 %, 28.9 %, and 14.8 % of the total identified reactions, respectively. Additionally, lignin-like substances were generated in large quantities, the overall humification level significantly increased, and the RI value increased for the penicillin intermediate, 6-aminopenicillanic acid (6-APA). Oxidation treatment effectively removed phosphorus-containing substances and some lignin-like substances produced by biological treatment; however, it was not effective in removing characteristic pollutants such as 6-APA. Such characteristic substances continued to be present in the effluent, and the DOM mainly contained protein- and humus-like substances, accounting for 30.8 % and 47.3 %, respectively. The study findings reveal the changes in organic matter and characteristic pollutants during the treatment of penicillin-containing wastewater from the perspective of the general molecular composition and specific molecular changes in DOM, providing support for further exploration of wastewater treatment mechanisms and improvements in treatment unit efficiency.

2.
J Morphol ; 285(9): e21773, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39252400

RÉSUMÉ

Nudibranchs, with their mesmerizing diversity and ecological significance, play crucial roles in marine ecosystems. Central to their feeding prowess is the radula, a chitinous structure with diverse morphologies adapted to prey preferences and feeding strategies. This study focuses on elucidating wear coping mechanisms in radular teeth of carnivorous molluscs, employing Dendronotus lacteus (Dendronotidae) and Flabellina affinis (Flabellinidae) as model species. Both species forage on hydrozoans. Through scanning electron microscopy, confocal laser scanning microscopy, nanoindentation, and energy-dispersive X-ray spectroscopy, the biomechanical and compositional properties of their teeth were analyzed. Notably, tooth coatings, composed of calcium (Ca) or silicon (Si) and high hardness and stiffness compared to the internal tooth structure, with varying mineral contents across tooth regions and ontogenetic zones, were found. The presence of the hard and stiff tooth coatings highlight their role in enhancing wear resistance. The heterogeneities in the autofluorescence patterns related to the distribution of Ca and Si of the coatings. Overall, this study provides into the biomechanical adaptations of nudibranch radular teeth, shedding light on the intricate interplay between tooth structure, elemental composition, and ecological function in marine molluscs.


Sujet(s)
Gastropoda , Dent , Animaux , Gastropoda/anatomie et histologie , Gastropoda/physiologie , Dent/anatomie et histologie , Microscopie électronique à balayage , Spectrométrie d'émission X , Phénomènes biomécaniques
3.
Heliyon ; 10(14): e34623, 2024 Jul 30.
Article de Anglais | MEDLINE | ID: mdl-39113999

RÉSUMÉ

The investigation of ancient artifacts is often constrained by their scarce availability and high protection and custody protocols. Among these, coinage represents an especially valuable kind-of-samples given their uniqueness and the subjacent information that is hidden behind their composition. Their analysis are often carried out using non-destructive techniques in order to avoid any alteration of the samples. In the field of Cultural Heritage analysis, smartphone-based methodologies have experienced a significant increase during the last few years, given their wide availability and ability to yield fast results. However, their analytical application demands a thorough and careful tuning during the methodology optimization. In this work, 21 historical gold and golden coins spanning a historical period of more than 2000 years have been analytically investigated. To that end, a two-fold approach has been implemented: first, the elemental composition has been analysed using portable X-ray fluorescence; and second, an innovative smartphone-based imaging method has been applied to measure their colour. Results allowed to describe the coins from their elemental profile, identifying some potentially debased ones, as well as some others not containing any gold. When possible, the results have been compared to previously reported cases, but our samples include some previously unreported cases representing new insights. All in all, this article provides new analytical data on unanalysed unique historical samples, in terms of their elemental profile and colorimetric properties, making use of an innovative, non-invasive nor destructive, fast and affordable colorimetric smartphone-based method to characterise historical coins.

4.
Molecules ; 29(15)2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-39125049

RÉSUMÉ

According to their nutritional value, their ability to adapt to the various environmental conditions, and their versatility, cereals are among the most cultivated plants in the world. However, the ongoing climate changes subject crops to important environmental stress that for some varieties leads to high production losses. Therefore, the selection of species and varieties that are more versatile and adaptable to different environmental conditions can be important. However, the characteristics of some cereals are not completely known; this is a priority before aiming to improve their cultivation. The aim of this study is to characterize select species that are potentially suitable for local environmental conditions and that possess nutritional value. The elemental composition was assessed in different cereal species grown following intensive and organic agriculture practices. Six species were grown for this study with techniques of intensive agriculture: Triticum monococcum L., Triticum dicoccum L., Triticum aestivum L., variety Verna, Triticum durum Desf., variety Senatore Cappelli, Triticum durum Desf., variety Claudio, and Avena strigosa Schreb.; four of these were also grown following organic procedures: Triticum monococcum L., Triticum dicoccum L., Triticum aestivum L., variety Verna, and Triticum durum Desf., variety Senatore Cappelli. The study considered twenty elements, including major nutrients (Ca, K, Mg, P, and S), seven micronutrients (B, Cu, Fe, Mn, Mo, Se, and Zn), and trace elements with toxic properties (Al, Ba, Cd, Cr, Na, Rb, Sc, and Sr) that can be accumulated at the seed level. The results highlight the differences in the element concentrations in the cereal seeds in relation to the genus and species; the highest concentrations of the major nutrients appeared in T. monococcum; the concentrations were 6.9, 2.09, 7.2, and 2.9 mg/g for K, Mg, P, and S, respectively. The highest concentrations of certain micronutrients, B, Ca, Mo, and Se (16, 785, 3.69, and 0.34 µg/g), were in A. strigosa. There is also evidence that the element content can be affected by the adopted cultivation procedure; however, the effects of the growing procedure can be significantly different when different species are considered. T. monococcum, grown by an organic procedure, presented lower concentrations of the major nutrients, while it demonstrated a modest increase in the micronutrients in the T. durum variety organic S. Cappelli, and the production procedure did not affect the elemental composition of the T. aestivum variety Verna. The survey also highlights that the studied species and the growing procedure affected the capacity to accumulate and translocate trace hazardous elements for human health at the seed level.


Sujet(s)
Grains comestibles , Triticum , Grains comestibles/composition chimique , Triticum/composition chimique , Agriculture biologique , Valeur nutritive , Oligoéléments/analyse , Produits agricoles/composition chimique , Produits agricoles/croissance et développement
5.
Sci Rep ; 14(1): 17992, 2024 Aug 03.
Article de Anglais | MEDLINE | ID: mdl-39097624

RÉSUMÉ

In the study presented here, the initial (that is, before the start of the process of natural hydrochemical influence) mineral formula of metamict polycrase in the composition of granite pegmatites of the Baltic Shield, applying an uranium natural half-leaching period, was calculated. To investigate the characteristics of immobilization of actinides in the studied polycrase, the absolute and relative uranium contents are compared with the corresponding uranium contents in the original betafite of the same deposit and age. It has been shown that over its geological history, betafite has lost up to 80% of its original uranium content. The proportion of uranium preserved in polycrase is twice as high. It is concluded that the difference in the relative content of uranium (27.3 wt% in polycrase and 31.6 wt% in betafite) cannot be the only reason for the complete oxidation of uranium in betafite, given that in polycrase 30% of uranium is preserved in the tetravalent state. It is more likely that the oxidation of uranium in betafite was primarily a result of the low ionicity of the chemical bonds compared to that in polycrase. This allows us to consider minerals of the euxenite group to be quite promising as matrix materials for the immobilization of actinides. At the same time, an opinion was expressed on the advisability of further comparative studies of Nb-Ta-Ti-oxides of the mineral groups AB2O6 and A2B2O7 for their use at the final stage of the nuclear fuel cycle.

6.
J Prosthodont ; 2024 Aug 26.
Article de Anglais | MEDLINE | ID: mdl-39188017

RÉSUMÉ

PURPOSE: To evaluate the effect of cleaning methods and thermocycling on the micro-tensile bond strength between resin cement and contaminated zirconia and to characterize the physicochemical alterations at the zirconia surface resulting from contaminants and subsequent application of cleaning methods. MATERIALS AND METHODS: Thirty-two alumina air-abraded zirconia blocks were divided into eight groups: (i) uncontaminated control followed by methacryloyloxydecyl dihydrogen phosphate (MDP) primer (G-Multi Primer) application (CON). In groups ii-viii, the blocks were contaminated with saliva and silicone disclosing agents, followed by cleaning as follows: (ii) MDP primer applied, followed by contamination (GMP1); (iii) MDP primer applied before and after contamination (GMP2); (iv) cleaning with alumina air-abrasion (APA); (v) cleaning with sodium hypochlorite (NaOCl); (vi) cleaning with Ivoclean (IVC); (vii) cleaning with ZirClean (ZC); and (viii) cleaning with Katana Cleaner (KC). After cleaning, the zirconia blocks in groups iv-viii were applied with MDP primer. The blocks in each group were cemented together with resin cement (G-Cem Linkforce). Subsequently, each bonded zirconia block was sectioned using a water-cooled diamond saw into microsticks (1 × 1 × 9 mm3). Micro-tensile bond strength was measured after either 24 h or 10,000 thermal cycles (n = 20/subgroup). Data were analyzed using two-way analysis of variance (ANOVA), followed by one-way ANOVA, and Tukey's post-hoc test. The contact angle measurements, energy dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared (FTIR) spectrometer were used for physiochemical evaluation. RESULTS: After 24 h of water storage, the highest bond strength was observed in the CON, NaOCl, APA, and GMP2 groups. After thermocycling, the bond strength significantly decreased in all groups except the GMP2 group, which maintained the highest bond strength. Commercial ceramic cleaning agents (IVC, ZC, and KC groups) exhibited lower bond strengths than the CON groups in both aging conditions. CONCLUSIONS: The application of MDP primer before and after contamination is a promising cleaning protocol for removing saliva and silicone disclosing agent contaminants from zirconia surfaces. This approach achieved the highest bond strength and maintained it even after artificial aging through thermocycling.

7.
Sci Total Environ ; 948: 174829, 2024 Oct 20.
Article de Anglais | MEDLINE | ID: mdl-39034012

RÉSUMÉ

Dust storms have great impacts on air quality and climate. Dust can influence cloud microphysical properties and determine their radiative forcing and precipitation. Asian dust storms (ADS) are important sources of global aerosol. However, the physiochemical characteristics of dust from ADS at a single particle level are less understood, and the exact particles that can serve as ice nucleating particles (INPs) remain unclear. Here, we present the physicochemical properties and ice nucleation ability of dust particles collected in Beijing during two major ADS in March 2021. The particles from two ADS were classified into Illite, Kaolinite, Feldspar, Quartz, Chlorite, Mixed-dust, and Non-dust particles, which contributed 28.6 % ± 3.3 %, 20.0 % ± 3.9 %, 12.3 % ± 2.3 %, 11.1 % ± 2.8 %, 9.8 % ± 0.8 %, 13.7 % ± 1.8 %, and 4.4 % ± 1.7 % in number, respectively. On average, the ADS particles formed ice crystals via deposition ice nucleation from relative humidity with respect to ice (RHice) of 112 % ± 1 % at 250 K to 154 % ± 15 % RHice at 205 K. Part of the samples also formed ice via immersion freezing between 230 K and 250 K. Among the 149 identified INPs, Clay-like particles (Chlorite, Illite, and Kaolinite) contributed 71.1 % ± 6.2 % in number and followed by Mixed-dust-like particles (16.9 % ± 8.7 %) and Feldspar-like particles (10.4 % ± 6.3 %). Enrichment factor of each particle type in INPs is calculated as the ratio of its number fractions in INPs and the aerosol population. It ranges from 0.6 ± 0.7 to 1.3 ± 2.2. The contribution of each particle type to INP was correlated with its fraction in the population. These results imply that each particle type can serve as INP. Clay-like particles are the dominant INPs during the ADS. We conducted ice nucleation kinetic analysis and provided parameterizations of heterogeneous ice nucleation rate coefficient and contact angle for ADS. These parameterizations can be used in the modeling study to evaluate the impact of ADS in atmospheric ice crystal formation in clouds.

8.
Phys Med Biol ; 69(16)2024 Aug 12.
Article de Anglais | MEDLINE | ID: mdl-39074494

RÉSUMÉ

Objective.Proton therapy allows for highly conformal dose deposition, but is sensitive to range uncertainties. Several approaches currently under development measure composition-dependent secondary radiation to monitor the delivered proton rangein-vivo. To fully utilize these methods, an estimate of the elemental composition of the patient's tissue is often needed.Approach.A published dual-energy computed tomography (DECT)-based composition-extraction algorithm was validated against reference compositions obtained with two independent methods. For this purpose, a set of phantoms containing either fresh porcine tissue or tissue-mimicking samples with known, realistic compositions were imaged with a CT scanner at two different energies. Then, the prompt gamma-ray (PG) signal during proton irradiation was measured with a PG detector prototype. The PG workflow used pre-calculated Monte Carlo simulations to obtain an optimized estimate of the sample's carbon and oxygen contents. The compositions were also assessed with chemical combustion analysis (CCA), and the stopping-power ratio (SPR) was measured with a multi-layer ionization chamber. The DECT images were used to calculate SPR-, density- and elemental composition maps, and to assign voxel-wise compositions from a selection of human tissues. For a more comprehensive set of reference compositions, the original selection was extended by 135 additional tissues, corresponding to spongiosa, high-density bones and low-density tissues.Results.The root-mean-square error for the soft tissue carbon and oxygen content was 8.5 wt% and 9.5 wt% relative to the CCA result and 2.1 wt% and 10.3 wt% relative to the PG result. The phosphorous and calcium content were predicted within 0.4 wt% and 1.1 wt% of the CCA results, respectively. The largest discrepancies were encountered in samples whose composition deviated the most from tabulated compositions or that were more inhomogeneous.Significance.Overall, DECT-based composition estimations of relevant elements were in equal or better agreement with the ground truth than the established SECT-approach and could contribute toin-vivodose verification measurements.


Sujet(s)
Fantômes en imagerie , Tomodensitométrie , Animaux , Suidae , Humains , Méthode de Monte Carlo
9.
Appl Microbiol Biotechnol ; 108(1): 408, 2024 Jul 05.
Article de Anglais | MEDLINE | ID: mdl-38967685

RÉSUMÉ

The simulations and predictions obtained from mathematical models of bioprocesses conducted by microorganisms are not overvalued. Mechanistic models are bringing a better process understanding and the possibility of simulating unmeasurable variables. The Dynamic Energy Budget (DEB) model is an energy balance that can be formulated for any living organism and can be classified as a structured model. In this study, the DEB model was used to describe E. coli growth in a batch reactor in carbon and nitrogen substrate limitation conditions. The DEB model provides a possibility to follow the changes in the microbes' cells including their elemental composition and content of some important cell ingredients in different growth phases in substrate limitation conditions which makes it more informative compared to Monod's model. The model can be used as an optimal choice between Monod-like models and flux-based approaches. KEY POINTS: • The DEB model can be used to catch changes in elemental composition of E. coli • Bacteria batch culture growth phases can be explained by the DEB model • The DEB model is more informative compared to Monod's based models.


Sujet(s)
Bioréacteurs , Carbone , Métabolisme énergétique , Escherichia coli , Azote , Escherichia coli/croissance et développement , Escherichia coli/métabolisme , Azote/métabolisme , Carbone/métabolisme , Bioréacteurs/microbiologie , Modèles biologiques , Milieux de culture/composition chimique , Techniques de culture cellulaire en batch , Modèles théoriques
10.
Ecol Evol ; 14(7): e11645, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39026962

RÉSUMÉ

Progress in the field of ecological stoichiometry has demonstrated that the outcome of ecological interactions can often be predicted a priori based on the nutrient ratios (e.g., carbon: nitrogen: phosphorus, C:N:P) of interacting organisms. However, the challenges of accurately measuring the nutrient content of active parasites within hosts has limited our ability to rigorously apply ecological stoichiometry to host-parasite systems. Traditional nutrient analyses require high parasite biomasses, often preventing individual-level analyses. This prevents researchers from estimating variation in the nutrient content of individual parasites within a single host infrapopulation, a critical factor that could define how the ecology of the parasite affects the host-parasite interaction. Here, we explain how energy dispersive technology, a technique currently used to measure the elemental content of free-living microbes, can be adapted for parasitic microbial infrapopulations. We demonstrate the power of accurately quantifying the biomass stoichiometry of individual microbial parasites sampled directly from individual hosts. Using this approach, we show that the stoichiometric composition of two microbial parasites capable of infecting the same host are stoichiometrically distinct and respond to host diet quality differently. We also demonstrate that characteristics of the stoichiometric trait distributions of these infrapopulations were important predictors of host fecundity, a proxy for virulence in this system, and better predictors of parasite load than the mean parasite stoichiometry or our parasite and diet treatments alone. EDS provides a rigorous tool for applying ecological stoichiometry to host-parasite systems and enables researchers to explore the nutritional physiology of host-parasite interactions at a scale that is more relevant to the ecology and evolution of the system than traditional nutrient analyses. Here we demonstrate that this level of resolution provides useful insights into the diet-dependent physiology of microbial parasites and their hosts. We anticipate that this improved level of resolution has the potential to elucidate a range of eco-evo interactions in host-parasite systems that were previously unobservable.

11.
Biol Trace Elem Res ; 2024 Jul 19.
Article de Anglais | MEDLINE | ID: mdl-39028479

RÉSUMÉ

In this study, we investigated the levels of macro, minor, and trace elements in roasted ground and instant coffees (n = 56). We assessed dietary mineral intake and health risks associated with potentially toxic elements (PTEs) using deterministic and probabilistic approaches. The limits of detection (LOD) ranged from 0.13 µg/kg for Be to 3.7 mg/kg for K, with corresponding limits of quantification (LOQ) at 0.43 µg/kg and 12.2 mg/kg. The recovery values (R%) ranged from 89 to 107%. The most abundant element was K, followed by Mg, Ca, and Na. Other elements followed this order: Fe > Mn > B > Cu > Sr > Zn > Al > Ba > Ni > Cr > Co > Se > Sn > Pb > Li > Ag > V > As > Cd > Hg > Be. Instant coffees generally exhibited higher K, Mg, and Na levels than ground-roasted coffees. Notably, Hg, Li, and Se were not detected in 34, 2, and 1 samples, respectively. Coffee samples were generally a good source of dietary elements such as Cu, Mn, Cr, and Se. The PTEs found in coffee products posed negligible risks to human health. The total target hazard quotient (TTHQ) remained below 1, and the incremental lifetime cancer risk (ILCR) did not exceed the threshold of 1 × 10-6. Nevertheless, coffee consumption contributed to Pb and As levels below 15% of the benchmark dose lower confidence limit (BMDL) values, and Sn, Hg, and Cd levels below 0.90% of the provisional tolerable weekly intake (PTWI).

12.
Article de Anglais | MEDLINE | ID: mdl-38929014

RÉSUMÉ

Metal workshops are workplaces with the substantial production of particulate matter (PM) with high metal content, which poses a significant health risk to workers. The PM produced by different metal processing techniques differs considerably in its elemental composition and size distribution and therefore poses different health risks. In some previous studies, the pollution sources were isolated under controlled conditions, while, in this study, we present a valuable alternative to characterize the pollution sources that can be applied to real working environments. Fine PM was sampled in five units (partially specializing in different techniques) of the same workshop. A total of 53 samples were collected with a temporal resolution of 30 min and 1 h. The mass concentrations were determined gravimetrically, and the elemental analysis, in which the concentrations of 14 elements were determined, was carried out using the X-ray fluorescence technique. Five sources of pollution were identified: background, steel grinding, metal active gas welding, tungsten inert gas welding, and machining. The sources were identified by positive matrix factorization, a statistical method for source apportionment. The identified sources corresponded well with the work activities in the workshop and with the actual sources described in previous studies. It is shown that positive matrix factorization can be a valuable tool for the identification and characterization of indoor sources.


Sujet(s)
Surveillance de l'environnement , Matière particulaire , Matière particulaire/analyse , Surveillance de l'environnement/méthodes , Métaux/analyse , Métallurgie , Exposition professionnelle/analyse , Polluants atmosphériques d'origine professionnelle/analyse , Pollution de l'air intérieur/analyse , Spectrométrie d'émission X
13.
Appl Radiat Isot ; 211: 111401, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38925037

RÉSUMÉ

Metallic elemental analyses are needed to complete food composition databases, in which humans consume food to obtain energy and be able to do everyday work. The study aimed to investigate the concentrations of some metals (K, Al, Fe, Cu, Cd, and Pb) in teff and barley samples using flame atomic absorption spectroscopy (FAAS) techniques. The samples, weighing 0.5 grams each, were subjected to wet digestions using a mixture ratio of 7:3(vol/vol) of HNO3 to H2O2 reagents at 90°c for 3:00 h under optimal conditions. The reagents were used to digest food samples for the presence of specific metallic elements. Flame Atomic Absorption Spectroscopy (FAAS) was used to analyze the mineral contents of the digested samples. The results demonstrated that the relative concentrations obtained in these cereal crops are different from one another. The concentration of metallic elements in mg/kg of K (2709.6±3.3), Al (952.3±4.2), Fe (320.9±4.8), Cu (25.3±3.2), Pb (ND) and Cd (ND) for red teff, K (3053.7±1.6), Al (1095.2±4.2), Fe (271.6±4.8), Cu (60.1±3.2), Pb (ND) and Cd (ND) for white teff while K (4333.3±3.2), Al (2595.2±4.2), Fe (74.0±0.00), Cu (10.5±1.8), Pb (ND) and Cd (ND) for barley. The high content of potassium and aluminum metallic elements was found in barley cereals. The results of this study will be useful in enriching the database of Ethiopian cereals as foods, advancing the knowledge of cereals and deepening the scientific understanding of the cereals.

14.
J Environ Manage ; 365: 121616, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38941854

RÉSUMÉ

Volcanic eruption is associated with the release of large volumes of pollutants in the environment, which can pose a risk to humans and other living organisms. The elemental and radioisotope composition of ash released during the Shiveluch Volcano eruption in 2023 was analyzed using ICP-MS and low-background gamma spectrometry. The ash consisted of 59% SiO2, 16.7% Al2O3, 5.3% CaO, 4.6 % Na2O, 4.5% Fe2O3, 1.4% K2O, 0.48% TiO2, 0.17% P2O5, 0.15% S, 0.078% MnO and 44 trace elements. Hazard Quotient and Hazard Index were calculated in order to evaluate the potential health risks to children and adults due to exposure to contaminants via inhalation, ingestion, and dermal contact. All values were below the unit, indicating a low probability of non-carcinogenic and cancerogenic risk occurrence in target groups. The average activity concentrations of the natural radionuclides were 350, 12.4 and 4.84 Bq/kg for 40K, 226Ra and 232Th. Radiological indices, including external and internal risk assessment, radium equivalent activity, annual effective dose, gamma index, and excess lifetime cancer risk were calculated to estimate the radiological hazard for the population. The values of all indices were below the recommended safety limits, indicating a low level of hazard for the exposed population.


Sujet(s)
Métaux , Radio-isotopes , Éruptions volcaniques , Humains , Métaux/analyse , Radio-isotopes/analyse , Radium/analyse , Appréciation des risques , Thorium/analyse
15.
Proc Natl Acad Sci U S A ; 121(23): e2312173121, 2024 Jun 04.
Article de Anglais | MEDLINE | ID: mdl-38805287

RÉSUMÉ

The year 2021 marked a decade of holopelagic sargassum (morphotypes Sargassum natans I and VIII, and Sargassum fluitans III) stranding on the Caribbean and West African coasts. Beaching of millions of tons of sargassum negatively impacts coastal ecosystems, economies, and human health. Additionally, the La Soufrière volcano erupted in St. Vincent in April 2021, at the start of the sargassum season. We investigated potential monthly variations in morphotype abundance and biomass composition of sargassum harvested in Jamaica and assessed the influence of processing methods (shade-drying vs. frozen samples) and of volcanic ash exposure on biochemical and elemental components. S. fluitans III was the most abundant morphotype across the year. Limited monthly variations were observed for key brown algal components (phlorotannins, fucoxanthin, and alginate). Shade-drying did not significantly alter the contents of proteins but affected levels of phlorotannins, fucoxanthin, mannitol, and alginate. Simulation of sargassum and volcanic ash drift combined with age statistics suggested that sargassum potentially shared the surface layer with ash for ~50 d, approximately 100 d before stranding in Jamaica. Integrated elemental analysis of volcanic ash, ambient seawater, and sargassum biomass showed that algae harvested from August had accumulated P, Al, Fe, Mn, Zn, and Ni, probably from the ash, and contained less As. This ash fingerprint confirmed the geographical origin and drift timescale of sargassum. Since environmental conditions and processing methods influence biomass composition, efforts should continue to improve understanding, forecasting, monitoring, and valorizing sargassum, particularly as strandings of sargassum show no sign of abating.


Sujet(s)
Biomasse , Sargassum , Sargassum/composition chimique , Écosystème , Jamaïque , Saisons , Éruptions volcaniques
16.
Article de Anglais | MEDLINE | ID: mdl-38700838

RÉSUMÉ

Elements such as As, Cd, Cr and Pb are classified as contaminants of major concern for public health, due to their high degree of toxicity. Saffron is an important medicinal herbal spice used in variety of food items, pharmaceutical medicines, and cosmetics. Presence of heavy metals in saffron will increase the health risk to consumers. Also, authentication of geographical origin of saffron is an issue of utmost importance for global trading. The present study is focused on investigation of elemental contaminants in saffron and elemental composition of saffron from India (Jammu and Kashmir); Iran and Afghanistan are also explored for geographical discrimination, using Chemometrics. In total, 29 elements including Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Si, Sr, Ti, Tl, V and Zn were analyzed using ICP-OES. Toxic elemental contaminants including As, Cd, Pb were found below the maximum permissible limit. Using PCA, elements B, Ni, Ba, Fe, V, Si, Al, Ti, K, Na, Sr, and Zn were found as significant discriminators of geographical origin. Elemental composition of saffron may be utilized, to prevent cases of falsified geographical origin in trade.


Sujet(s)
Crocus , Contamination des aliments , Crocus/composition chimique , Contamination des aliments/analyse , Métaux lourds/analyse , Chimiométrie , Inde , Iran , Afghanistan , Géographie
17.
BMC Urol ; 24(1): 114, 2024 May 30.
Article de Anglais | MEDLINE | ID: mdl-38816700

RÉSUMÉ

BACKGROUND: Urolithiasis has emerged as a global affliction, recognized as one of the most excruciating medical issues. The elemental composition of stones provides crucial information, aiding in understanding the causes, mechanisms, and individual variations in stone formation. By understanding the interactions between elements in various types of stones and exploring the key role of elements in stone formation, insights are provided for the prevention and treatment of urinary stone disease. METHODS: This study collected urinary stone samples from 80 patients in Beijing. The chemical compositions of urinary stones were identified using an infrared spectrometer. The concentrations of major and trace elements in the urinary stones were determined using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS), respectively. The data were processed using correlation analysis and Principal Component Analysis (PCA) methods. RESULTS: Urinary stones are categorized into five types: the calcium oxalate (CO) stone, carbonate apatite (CA) stone, uric acid (UA) stone, mixed CO and CA stone, and mixed CO and UA stone. Ca is the predominant element, with an average content ranging from 2.64 to 27.68% across the five stone groups. Based on geochemical analysis, the high-content elements follow this order: Ca > Mg > Na > K > Zn > Sr. Correlation analysis and PCA suggested significant variations in the interactions between elements for different types of urinary stones. Trace elements with charges and ionic structures similar to Ca may substitute for Ca during the process of stone formation, such as Sr and Pb affecting the Ca in most stone types except mixed stone types. Moreover, the Mg, Zn and Ba can substitute for Ca in the mixed stone types, showing element behavior dependents on the stone types. CONCLUSION: This study primarily reveals distinct elemental features associated with five types of urinary stones. Additionally, the analysis of these elements indicates that substitutions of trace elements with charges and ion structures similar to Ca (such as Sr and Pb) impact most stone types. This suggests a dependence of stone composition on elemental behavior. The findings of this study will enhance our ability to address the challenges posed by urinary stones to global health and improve the precision of interventions for individuals with different stone compositions.


Sujet(s)
Oligoéléments , Calculs urinaires , Humains , Calculs urinaires/composition chimique , Oligoéléments/analyse , Adulte d'âge moyen , Femelle , Mâle , Adulte , Oxalate de calcium/analyse , Sujet âgé , Acide urique/analyse , Acide urique/urine , Jeune adulte
18.
Plants (Basel) ; 13(4)2024 Feb 09.
Article de Anglais | MEDLINE | ID: mdl-38498449

RÉSUMÉ

(1) Background: This study provides novel insights into the elemental content and biomineralization processes of two halophytic species of the genus Arthrocnemum Moq. (A. macrostachyum and A. meridionale). (2) Methods: Elemental content was analyzed using ICP-MS, while biominerals were detected through electron microscopy (SEM and TEM) and X-ray diffraction. (3) Results: The elemental content showed significant concentrations of macronutrients (sodium, potassium, magnesium, and calcium) and micronutrients, especially iron. Iron was consistently found as ferritin in A. macrostachyum chloroplasts. Notably, A. macrostachyum populations from the Center of the Iberian Peninsula exhibited exceptionally high magnesium content, with values that exceeded 40,000 mg/kg d.w. Succulent stems showed elemental content consistent with the minerals identified through X-ray diffraction analysis (halite, sylvite, natroxalate, and glushinskite). Seed analysis revealed elevated levels of macro- and micronutrients and the absence of heavy metals. Additionally, the presence of reduced sodium chloride crystals in the seed edges suggested a mechanism to mitigate potential sodium toxicity. (4) Conclusions: These findings highlight the potential of Arthrocnemum species as emerging edible halophytes with nutritional properties, particularly in Western European Mediterranean territories and North Africa. They offer promising prospects for biosaline agriculture and biotechnology applications.

19.
Sci Rep ; 14(1): 4695, 2024 02 26.
Article de Anglais | MEDLINE | ID: mdl-38409429

RÉSUMÉ

Insect feeding structures, such as mandibles, interact with the ingesta (food or/and substrate) and can be adapted in morphology, composition of material and mechanical properties. The foraging on abrasive ingesta, as on algae covering rocks, is particularly challenging because the mandibles will be prone to wear and structural failure, thus suggesting the presence of mandibular adaptations to accompany this feeding behavior. Adaptations to this are well studied in the mouthparts of molluscs and sea urchins, but for insects there are large gaps in our knowledge. In this study, we investigated the mandibles of a grazing insect, the larvae of the trichopteran Glossosoma boltoni. Using scanning electron microscopy, wear was documented on the mandibles. The highest degree was identified on the medial surface of the sharp mandible tip. Using nanoindentation, the mechanical properties, such as hardness and Young's modulus, of the medial and lateral mandible cuticles were tested. We found, that the medial cuticle of the tip was significantly softer and more flexible than the lateral one. These findings indicate that a self-sharpening mechanism is present in the mandibles of this species, since the softer medial cuticle is probably abraded faster than the harder lateral one, leading to sharp mandible tips. To investigate the origins of these properties, we visualized the degree of tanning by confocal laser scanning microscopy. The autofluorescence signal related to the mechanical property gradients. The presence of transition and alkaline earth metals by energy dispersive X-ray spectroscopy was also tested. We found Ca, Cl, Cu, Fe, K, Mg, Mn, P, S, Si, and Zn in the cuticle, but the content was very low and did not correlate with the mechanical property values.


Sujet(s)
Holometabola , Insectes , Animaux , Larve , Microscopie électronique à balayage , Mandibule/anatomie et histologie
20.
Talanta ; 272: 125738, 2024 May 15.
Article de Anglais | MEDLINE | ID: mdl-38359717

RÉSUMÉ

The sulfidation is considered as one of the most important environmental transformation processes of silver nanoparticles (AgNPs), which affects their transport, uptake and toxicity. Herein, based on the hollow fiber flow-field flow fractionation coupled with triple quadrupole inductively coupled plasma mass spectrometry (HF5-ICP-QQQ), we developed an efficient approach to accurately characterize the sulfidation process of AgNPs in aquatic solutions. HF5 could efficiently remove interferential ions and separate nanoparticles with different sizes online, and ICP-QQQ could accurately detect S element through monitoring 32S16O+ in mass shift mode. By the proposed method, two kinds of AgNPs, citrate-coated AgNPs and PVP-coated AgNPs, were selected as models to trace their transfer behaviors during the sulfidation. The results showed once AgNPs were exposed to Na2S solution, the overlapping fractograms of 32S16O+ and 107Ag+ were rapidly detected by HF5-ICP-QQQ to indicate the co-presence of Ag and S, and thus confirming the production of Ag2S and AgNPs underwent a rapid sulfidation process. There were substantial differences in the influence of the two coated agents on the stability of the particles under the conditions examined. In the presence of sulfide, PVP-coated AgNPs could maintain initial size distribution with higher stability, while the size distribution of citrate-coated AgNPs changed considerably. The developed HF5-ICP-QQQ method provides a reliable tool to identify and characterize the transformation process of AgNPs in aquatic solution, which contributed to a deeper understanding of the environmental fate and behavior of AgNPs with different coating.

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