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1.
Wei Sheng Yan Jiu ; 53(2): 267-274, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38604963

RESUMO

OBJECTIVE: To investigate the association of metals/metalloids exposure with risk of liver disfunction among occupational population in Hunan Province, and to explore the potential dose-response relationship. METHODS: In 2017, a mining area in Hunan Province was chosen as the research site, and eligible workers were recruited as study subjects. General demographic characteristics, levels of 23 metals/metalloids in plasma and urine, and liver function index(total bilirubin(TBIL), alanine amino transferase(ALT), globulin(GLB) and γ-glutamyl transferase(GGT)) were obtained by questionnaire, physical examination and laboratory tests. Participants were followed up in 2018, 2019 and 2020 respectively. Cox proportional risk model was used to evaluate the relationship between metal/metalloids exposure and risk of liver disfunction, and dose-response relationship curves were plotted by using the restricted cubic spline function. RESULTS: A total of 891 employees were recruited in the study, 576(65.0%)were aged ≤45 years, 832(93.4%) were male and 530(59.5%) worked as smelters. After adjusting various factors such as age, gender, BMI, type of work, education, smoking, alcohol consumption, diet, stress, medical history, exercise and tea consumption, positive correlations were found between plasma tungsten(HR=4.90, 95%CI 1.17-20.48) and urinary barium(HR=1.07, 95%CI 1.02-1.12) levels with abnormally elevated TBIL levels. Additionally, a significant association was observed between plasma thallium and the risk of elevated ALT levels(HR=11.15, 95%CI 1.97-63.29). CONCLUSION: Plasma tungsten and thallium, along with barium found in urine, are risk factors for the development of abnormally elevated liver function indices in occupational groups.


Assuntos
Hepatopatias , Metaloides , Humanos , Masculino , Feminino , Estudos Prospectivos , Tálio , Bário , Tungstênio , Metais
2.
PeerJ ; 12: e17200, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577416

RESUMO

Background: Dayu County, a major tungsten producer in China, experiences severe heavy metal pollution. This study evaluated the pollution status, the accumulation characteristics in paddy rice, and the potential ecological risks of heavy metals in agricutural soils near tungsten mining areas of Dayu County. Furthermore, the impacts of soil properties on the accumulation of heavy metals in soil were explored. Methods: The geo-accumulation index (Igeo), the contamination factor (CF), and the pollution load index (PLI) were used to evaluate the pollution status of metals (As, Cd, Cu, Cr, Pb, Mo, W, and Zn) in soils. The ecological risk factor (RI) was used to assess the potential ecological risks of heavy metals in soil. The health risks and accumulation of heavy metals in paddy rice were evaluated using the health risk index and the translocation factor (TF), respectively. Pearson's correlation coefficient was used to discuss the influence of soil factors on heavy metal contents in soil. Results: The concentrations of metals exceeded the respective average background values for soils (As: 10.4, Cd: 0.10, Cu: 20.8, Cr: 48.0, Pb: 32.1, Mo: 0.30, W: 4.93, Zn: 69.0, mg/kg). The levels of As, Cd, Mo, and tungsten(W) exceeded the risk screening values for Chinese agricultural soil contamination and the Dutch standard. The mean concentrations of the eight tested heavy metals followed the order FJ-S > QL > FJ-N > HL > CJ-E > CJ-W, with a significant distribution throughout the Zhangjiang River basin. Heavy metals, especially Cd, were enriched in paddy rice. The Igeo and CF assessment indicated that the soil was moderately to heavily polluted by Mo, W and Cd, and the PLI assessment indicated the the sites of FJ-S and QL were extremely severely polluted due to the contribution of Cd, Mo and W. The RI results indicated that Cd posed the highest risk near tungsten mining areas. The non-carcinogenic and total carcinogenic risks were above the threshold values (non-carcinogenic risk by HQ > 1, carcinogenic risks by CR > 1 × 10-4 a-1) for As and Cd. Correlation analysis indicated that K2O, Na2O, and CaO are main factors affecting the accumulation and migration of heavy metals in soils and plants. Our findings reveal significant contamination of soils and crops with heavy metals, especially Cd, Mo, and W, near mining areas, highlighting serious health risks. This emphasizes the need for immediate remedial actions and the implementation of stringent environmental policies to safeguard health and the environment.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Solo , Tungstênio/análise , Cádmio/análise , Chumbo/análise , Monitoramento Ambiental , Medição de Risco , Poluentes do Solo/análise , Metais Pesados/análise , Mineração , China
3.
J Hazard Mater ; 470: 134198, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608582

RESUMO

A novel Ag3PO4/ZnWO4-modified graphite felt electrode (AZW@GF) was prepared by drop coating method and applied to photoelectrocatalytic removal of harmful algae. Results showed that approximately 99.21% of chlorophyll a and 91.57% of Microcystin-LR (MCLR) were degraded by the AZW@GF-Pt photoelectrocatalytic system under the optimal operating conditions with a rate constant of 0.02617 min-1 and 0.01416 min-1, respectively. The calculated synergistic coefficient of photoelectrocatalytic algal removal and MC-LR degradation by the AZW@GF-Pt system was both larger than 1.9. In addition, the experiments of quenching experiments and electron spin resonance (ESR) revealed that the photoelectrocatalytic reaction mainly generated •OH and •O2- for algal removal and MC-LR degradation. Furthermore, the potential pathway for photoelectrocatalytic degradation of MC-LR was proposed. Finally, the photoelectrocatalytic cycle algae removal experiments were carried out on AZW@GF electrode, which was found to maintain the algae removal efficiency at about 91% after three cycles of use, indicating that the photoelectrocatalysis of AZW@GF electrode is an effective emergency algae removal technology.


Assuntos
Eletrodos , Grafite , Toxinas Marinhas , Microcistinas , Compostos de Prata , Grafite/química , Grafite/efeitos da radiação , Microcistinas/química , Microcistinas/isolamento & purificação , Catálise , Compostos de Prata/química , Fosfatos/química , Óxidos/química , Técnicas Eletroquímicas , Tungstênio/química , Clorofila A/química , Zinco/química , Purificação da Água/métodos , Clorofila/química , Processos Fotoquímicos , Proliferação Nociva de Algas
4.
Luminescence ; 39(3): e4714, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38506395

RESUMO

In this study, the melt quenching approach is used to synthesize a lead borate-strontium-based glass system doped with samarium ions. Modifications in the glass network structure arising from the addition of various concentrations of Sm3+ ions were investigated via Fourier transform infrared (FTIR) spectroscopy. FTIR analysis revealed B-O-B bridges, BO3 , and BO4 units are present. UV-vis-NIR spectroscopic measurement was performed to study the optical absorption spectra. Optical constants such as optical bandgap energies, refractive indices, and other related parameters were evaluated. The lifetime fluorescence decay was measured and ranged between 1.04 and 1.88 ns. The photoluminescence spectra in the range 500-750 nm revealed four transitions from the ground state 6 G5/2 to the excited states 6 H5/2 , 6 H7/2 , 6 H9/2 and 6 H11/2 and J-O theory was utilized to study these optical transitions for Sm3+ ions. Calculations of the oscillator strengths and J-O intensity parameters were performed and the obtained J-O parameters followed the sequence Ω4 > Ω6 > Ω2 . The ratio O/R indicated a high lattice asymmetry around the samarium ions. The values of lifetimes and branching ratios for the fabricated samples emphasized their suitability to be used in laser applications. The current glass samples are good candidates for orange and red emission devices.


Assuntos
Boratos , Tungstênio , Boratos/química , Samário/química , Íons , Vidro/química
5.
Sci Total Environ ; 924: 171429, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38442750

RESUMO

The growth of pioneer plants in metal mining area soil is closely related to their minimal uptake of toxic elements. Pioneer plants can inhibit the uptake of toxic elements by increasing nutrient uptake. However, few studies have focused on the mechanisms by which the rhizosphere microbiome affect nutrient cycling and their impact on the uptake of toxic elements by pioneer plants. In this study, we selected Blechnum orientale to investigate the potential roles of the rhizosphere microbiome in nutrient cycling and plant growth in a historical tungsten (W) mining area. Our results showed that while the arsenic (As) and W contents in the soil were relatively high, the enrichment levels of As and W in the B. orientale were relatively low. Furthermore, we found that the As and W contents in plants were significantly negatively correlated with soil nutrients (S, P and Mo), suggesting that elevated levels of these soil nutrients could inhibit As and W uptake by B. orientale. Importantly, we found that these nutrients were also identified as the most important factors shaping rhizosphere microbial attributes, including microbial diversity, ecological clusters, and keystone OTUs. Moreover, the genera, keystone taxa and microbial functional genes enriched in the rhizosphere soils from mining areas played a key role in nutrient (S, P and Mo) bioavailability, which could further increase the nutrient uptake by B. orientale. Taken together, our results suggest that rhizosphere microorganisms can improve pioneer plant growth by inhibiting toxic element accumulation via the increase in nutrient cycling in former W mining areas.


Assuntos
Arsênio , Gleiquênias , Microbiota , Traqueófitas , Arsênio/análise , Tungstênio , Rizosfera , Solo , Plantas , Mineração , Microbiologia do Solo
6.
Environ Pollut ; 347: 123746, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38460585

RESUMO

Mitigating pharmaceutical pollution in the global environment is imperative, and tetracycline (TC) is a commonly utilized antibiotic in human and veterinary medicine. The persistent existence of TC highlights the necessity of establishing efficient measures to protect water systems and the environment from detrimental contaminants. Herein, a novel rhubarb seed waste-derived activated carbon-supported photocatalyst (WO3-ZnO/RUAC) was synthesized by combining wet impregnation and ultrasonic methods. The activated carbon (AC) was obtained from rhubarb seed waste for the first time via chemical activation. The function of AC as an electron acceptor and in separating electron-hole pairs was illuminated by characterization analyses that included XRD, FTIR, XPS, SEM, TEM, PL, EIS, TPC, and UV-DRS. Using the response surface methodology-central composite design (RSM-CCD) technique, the synthesis parameters of the composite were systematically optimized. Under ideal conditions, with a TC concentration of 33 mg. L-1, pH of 4.57, irradiation time of 108 min, and catalyst dose of 0.85 g. L-1, the highest degradation efficiency of TC by this composite, achieved 96.5%, and it was reusable for five cycles. Subsequently, trapping tests and electron spin resonance (ESR) analysis were conducted, elucidating that •OH and •O2- radicals played pivotal roles in the photocatalytic degradation of TC. This research offers valuable insights into utilizing the AC-based photocatalyst to degrade pharmaceutical micropollutants effectively.


Assuntos
Óxido de Zinco , Antibacterianos/química , Catálise , Carvão Vegetal , Luz , Preparações Farmacêuticas , Tetraciclina/química , Tungstênio , Óxido de Zinco/química
7.
J Inorg Biochem ; 255: 112543, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38554579

RESUMO

Acetylene hydratase is currently the only known mononuclear tungstoenzyme that does not catalyze a net redox reaction. The conversion of acetylene to acetaldehyde is proposed to occur at a W(IV) active site through first-sphere coordination of the acetylene substrate. To date, a handful of tungsten complexes have been shown to bind acetylene, but many lack the bis(dithiolene) motif of the native enzyme. The model compound, [W(O)(mnt)2]2-, where mnt2- is 1,2-dicyano-1,2-dithiolate, was previously reported to bind an electrophilic acetylene substrate, dimethyl acetylenedicarboxylate, and characterized by FT-IR, UV-vis, potentiometry, and mass spectrometry (Yadav, J; Das, S. K.; Sarkar, S., J. Am. Chem. Soc., 1997, 119, 4316-4317). By slightly changing the electrophilic acetylene substrate, an acetylenic-bis(dithiolene)­tungsten(IV) complex has been isolated and characterized by FT-IR, UV-vis, NMR, X-ray diffraction, and X-ray absorption spectroscopy. Activation parameters for complex formation were also determined and suggest coordination-sphere reorganization is a limiting factor in the model complex reactivity.


Assuntos
Acetileno , Tungstênio , Acetileno/química , Tungstênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Hidroliases/química
8.
Food Chem ; 448: 138994, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38522301

RESUMO

Integrating a pre-enrichment step into electrochemical detection methodologies has traditionally been employed to enhance the performance of heavy metal detection. However, this augmentation also introduces a degree of intricacy into the sensing process and increases energy consumption. In this work, Mo-doped WO3 is grown in situ on carbon cloth by one-step electrodeposition. The electrode detect multiple heavy metal ions simultaneously in the range of 0.1-100.0 µM with LODs ranging from 11.2 to 17.1 nM. The electrode successfully detected heavy metal ions in diverse food samples. This pioneering detection strategy realized the direct and simultaneous detection of multiple heavy metal ions by utilizing the valence property of WO3 and oxygen vacancies generated by molybdenum doping. The Mo-WO3/CC pre-enrichment-free detection electrode boasts straightforward preparation, a streamlined detection procedure, swift response kinetics, and superior performance relative to previously reported electrodes, which makes it possible to develop a portable heavy metal ion detection device.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Contaminação de Alimentos , Metais Pesados , Molibdênio , Tungstênio , Metais Pesados/análise , Contaminação de Alimentos/análise , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Tungstênio/química , Molibdênio/química , Óxidos/química , Limite de Detecção , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos
9.
J Hazard Mater ; 470: 134118, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38547752

RESUMO

Urine is the major source of nitrogen pollutants in domestic sewage and is a neglected source of H2. Although ClO• is used to overcome the poor selectivity and slow kinetics of urea decomposition, the generation of ClO• suffers from the inefficient formation reaction of HO• and reactive chlorine species (RCS). In this study, a synergistic catalytic method based on TiO2/WO3 photoanode and Sb-SnO2 electrode efficiently producing ClO• is proposed for urine treatment. The critical design is that TiO2/WO3 photoanode and Sb-SnO2 electrode that generate HO• and RCS, respectively, are assembled in a confined space through face-to-face (TiO2/WO3//Sb-SnO2), which effectively strengthens the direct reaction of HO• and RCS. Furthermore, a Si solar panel as rear photovoltaic cell (Si PVC) is placed behind TiO2/WO3//Sb-SnO2 to fully use sunlight and provide the driving force of charge separation. The composite photoanode (TiO2/WO3//Sb-SnO2 @Si PVC) has a ClO• generation rate of 260% compared with the back-to-bake assembly way. In addition, the electrons transfer to the NiFe LDH@Cu NWs/CF cathode for rapid H2 production by the constructed photoelectric catalytic (PEC) cell without applied external biasing potential, in which the H2 production yield reaches 84.55 µmol h-1 with 25% improvement of the urine denitrification rate. The superior performance and long-term stability of PEC cell provide an effective and promising method for denitrification and H2 generation.


Assuntos
Antimônio , Eletrodos , Óxidos , Compostos de Estanho , Titânio , Tungstênio , Titânio/química , Tungstênio/química , Compostos de Estanho/química , Catálise , Antimônio/química , Óxidos/química , Urina/química , Cloro/química , Radical Hidroxila/química
10.
Zootaxa ; 5415(2): 321-332, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38480201

RESUMO

In this study, the Perlidae stonefly collections of Dr. Wolfram Mey from over 20 years ago have been examined. Neoperla jhoanae sp. nov. from Central Luzon Region and Neoperla nagaensis sp. nov. from Bicol Region are described herein. Additional records and information are also provided on Neoperla jewetti Sivec, 1984, Neoperla recta Banks, 1913, Neoperla pseudorecta Sivec, 1984, Neoperla oculata Banks, 1924, Neoperla nigra Sivec, 1984, Phanoperla bakeri (Banks, 1924), and Phanoperla flaveola (Klaplek, 1910).


Assuntos
Insetos , Tungstênio , Animais , Filipinas , Distribuição Animal , Neópteros
11.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473818

RESUMO

Polyoxotungstate nanoclusters have recently emerged as promising contrast agents for computed tomography (CT). In order to evaluate their clinical potential, in this study, we evaluated the in vitro CT imaging properties, potential toxic effects in vivo, and tissue distribution of monolacunary Wells-Dawson polyoxometalate, α2-K10P2W17O61.20H2O (mono-WD POM). Mono-WD POM showed superior X-ray attenuation compared to other tungsten-containing nanoclusters (its parent WD-POM and Keggin POM) and the standard iodine-based contrast agent (iohexol). The calculated X-ray attenuation linear slope for mono-WD POM was significantly higher compared to parent WD-POM, Keggin POM, and iohexol (5.97 ± 0.14 vs. 4.84 ± 0.05, 4.55 ± 0.16, and 4.30 ± 0.09, respectively). Acute oral (maximum-administered dose (MAD) = 960 mg/kg) and intravenous administration (1/10, 1/5, and 1/3 MAD) of mono-WD POM did not induce unexpected changes in rats' general habits or mortality. Results of blood gas analysis, CO-oximetry status, and the levels of electrolytes, glucose, lactate, creatinine, and BUN demonstrated a dose-dependent tendency 14 days after intravenous administration of mono-WD POM. The most significant differences compared to the control were observed for 1/3 MAD, being approximately seventy times higher than the typically used dose (0.015 mmol W/kg) of tungsten-based contrast agents. The highest tungsten deposition was found in the kidney (1/3 MAD-0.67 ± 0.12; 1/5 MAD-0.59 ± 0.07; 1/10 MAD-0.54 ± 0.05), which corresponded to detected morphological irregularities, electrolyte imbalance, and increased BUN levels.


Assuntos
Ânions , Meios de Contraste , Iohexol , Polieletrólitos , Ratos , Animais , Distribuição Tecidual , Tungstênio , Tomografia Computadorizada por Raios X
12.
Microb Pathog ; 189: 106571, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341107

RESUMO

Nanomaterials containing tungsten (TNMs), characterized by diverse nanostructures had been extensively used in biomedical sector. Despite numerous reports focusing on TNM applications in specific biomedical areas, there is a noticeable absence of comprehensive studies that focused on detailed characterization of nanomaterials along with their biological applications. The present work described the structural, morphological, and antimicrobial properties of tungsten oxide (WO3) nanoparticles coated by antibiotics (nanobiotics), and their application on single and mixed bacterial culture. The nanobiotics included in this study were WO3 coated with ampicillin (W+A), WO3 coated with penicillin (P+W), and WO3 coated with ciprofloxacin (C+W). Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray spectroscopy (EDX), Fourier transforms infrared spectroscopy (FTIR), Rrman spectroscopy, and UV-visible spectroscopy were used to characterize synthesized nanoparticles. The minimum inhibitory concentration of C+W nanobiotic against S. aureus, E. coli, and mixed culture (S. aureus +E. coli) was lower than that of P+W and A+W. The impact of incubation period showed significant differences for each of nanobiotic against S. aureus, E. coli, and mixed culture. However, there were also non-significant differences among incubation periods for antibacterial activity of nanobiotics. It was pertinent to note that percentage variation in susceptibility of S. aureus with respect to mixed culture remained higher as compared to E. coli, indicating it stronger candidate imposing resistance. This paper thus suggested the strategy of coating of antibiotics with with WO3 nanoparticles as an ideal combination for resistance modulation against single and mixed culture bacteria.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Óxidos , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Tungstênio/farmacologia , Tungstênio/química , Escherichia coli , Staphylococcus aureus , Ciprofloxacina/farmacologia , Bactérias , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química , Difração de Raios X
13.
Int J Biol Macromol ; 261(Pt 2): 129962, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316322

RESUMO

In this work, novel monoclinic tungsten oxide (WO3)-encapsulated phosphate-rich porous sodium alginate (PASA) microspherical hydrogel beads were prepared for efficient U(VI) capture. These macroporous and hollow beads were systematically characterized through XRD, FTIR, EDX-mapping, and SEM-EDS techniques. The O and P atoms in the PO and monoclinic WO3 offered inner-spherical complexation with U(VI). The in situ growth of WO3 played a significant role inside the phosphate-rich biopolymeric network to improve its chemical stability, specific surface area, adsorption capacity, and sorption rate. The phytic acid (PA) served for heteroatom doping and crosslinking. The encapsulated WO3 mass ratio was optimized in different composites, and WO3/PASA3 (the microspherical beads with a mass ratio of 30.0 % w/w) exhibited remarkable maximum sorption capacity qm (336.42 mg/g) computed through the best-fit Langmuir model (R2 ≈ 0.99) and rapid sorption equilibrium, teq (150 min). The isothermal sorption studies were conducted at different temperatures (298, 303, and 308 K) and thermodynamic parameters concluded that the process of U(VI) sorption using WO3/PASA3 is endothermic and feasible having ΔHo (8.19 kJ/mol), ΔGo (-20.75, -21.38, and - 21.86 kJ/mol) and proceeds with a minute increase in randomness ΔSo (0.09 kJ/mol.K). Tungsten oxide (WO3)-encapsulated phosphate-rich porous microspherical beads could be promising material for uranium removal.


Assuntos
Alginatos , Óxidos , Tungstênio , Urânio , Alginatos/química , Adsorção , Fosfatos , Porosidade , Termodinâmica , Cinética , Urânio/química , Concentração de Íons de Hidrogênio
14.
Food Funct ; 15(5): 2706-2718, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38376466

RESUMO

Dietary intake can modify the impact of metals on human health, and is also closely related to glucose metabolism in human bodies. However, research on their interaction is limited. We used data based on 1738 adults aged ≥20 years from the National Health and Nutrition Examination Survey 2011-2016. We combined linear regression and restricted cubic splines with Bayesian kernel machine regression (BKMR) to identify metals associated with each glucose metabolism index (P < 0.05 and the posterior inclusion probabilities of BKMR >0.5) in eight non-essential heavy metals (barium, cadmium, antimony, tungsten, uranium, arsenic, lead, and thallium) and glucose metabolism indexes [fasting plasma glucose (FPG), blood hemoglobin A1c (HbA1c) and homeostatic model assessment of insulin resistance (HOMA-IR)]. We identified two pairs of metals associated with glucose metabolism indexes: cadmium and tungsten to HbA1c and barium and thallium to HOMA-IR. Then, the cross-validated kernel ensemble (CVEK) approach was applied to identify the specific nutrient group (nutrients) that interacted with the association. By using the CVEK model, we identified significant interactions between the energy-adjusted diet inflammatory index (E-DII) and cadmium, tungsten and barium (all P < 0.05); macro-nutrients and cadmium, tungsten and barium (all P < 0.05); minerals and cadmium, tungsten, barium and thallium (all P < 0.05); and A vitamins and thallium (P = 0.043). Furthermore, a lower E-DII, a lower intake of carbohydrates and phosphorus, and a higher consumption of magnesium seem to attenuate the positive association between metals and glucose metabolism indexes. Our finding identifying the nutrients that interact with non-essential heavy metals could provide a feasible nutritional guideline for the general population to protect against the adverse effects of non-essential heavy metals on glucose metabolism.


Assuntos
Cádmio , Metais Pesados , Adulto , Humanos , Inquéritos Nutricionais , Bário , Tálio , Tungstênio , Hemoglobinas Glicadas , Teorema de Bayes , Glucose
15.
Chemosphere ; 346: 140576, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303401

RESUMO

Photocatalytic dye degradation employing polyoxometalates (POMs) has been a research focus for several years. We report the facile synthesis of tungsten-based Lindqvist and Keggin-type POMs that degrade toxic chemical dyes, methyl orange (MO) and methylene blue (MB), respectively. The Lindqvist POM, sodium hexatungstate, Na2W6O19, degrades MO under 100 W UV light irradiation within 15 min, whereas the Keggin POM, Ag4PW11VO40, degrades MB under 20 W visible light source within 180 min. The effect of various operating parameters, such as photocatalyst concentration, pH, time, and initial dye concentration, were assessed in the degradation of both dyes. The photoelectrochemical performance of the as-synthesized polyoxometalates shows that the Ag4PW11VO40 shows 2.4 times higher photocurrent density than Na2W6O19 at a potential of 0.9 V vs. Ag/AgCl. Electrochemical impedance analysis reveals that Ag4PW11VO40 exhibits much lower charge transfer resistance as compared to Na2W6O19, which indicates facile charge transfer at the electrode-electrolyte interface. Further Mott-Schottky measurements reveal that both the catalysts possess n-type semiconductivity and the charge carrier concentration of Ag4PW11VO40 (5.89 × 1019 cm-3) is 1.4 times higher as compared to Na2W6O19 (4.25 × 1019 cm-3). This work offers a new paradigm for designing polyoxometalates suitable for efficient photocatalytic degradation of organic dyes.


Assuntos
Ânions , Compostos Azo , Corantes , Polieletrólitos , Tungstênio , Luz
16.
J Clin Hypertens (Greenwich) ; 26(2): 187-196, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38214193

RESUMO

There are limited data available regarding the connection between hypertension and heavy metal exposure. The authors intend to establish an interpretable machine learning (ML) model with high efficiency and robustness that identifies hypertension based on heavy metal exposure. Our datasets were obtained from the US National Health and Nutrition Examination Survey (NHANES, 2013-2020.3). The authors developed 5 ML models for hypertension identification by heavy metal exposure, and tested them by 10 discrimination characteristics. Further, the authors chose the optimally performing model after parameter adjustment by Genetic Algorithm (GA) for identification. Finally, in order to visualize the model's ability to make decisions, the authors used SHapley Additive exPlanation (SHAP) and Local Interpretable Model-Agnostic Explanations (LIME) algorithm to illustrate the features. The study included 19 368 participants in total. A best-performing eXtreme Gradient Boosting (XGB) with GA for hypertension identification by 16 heavy metals was selected (AUC: 0.774; 95% CI: 0.772-0.776; accuracy: 87.7%). According to SHAP values, Barium (0.02), Cadmium (0.017), Lead (0.017), Antimony (0.008), Tin (0.007), Manganese (0.006), Thallium (0.004), Tungsten (0.004) in urine, and Lead (0.048), Mercury (0.035), Selenium (0.05), Manganese (0.007) in blood positively influenced the model, while Cadmium (-0.001) in urine negatively influenced the model. Study participants' hypertension associated with heavy metal exposure was identified by an efficient, robust, and interpretable GA-XGB model with SHAP and LIME. Barium, Cadmium, Lead, Antimony, Tin, Manganese, Thallium, Tungsten in urine, and Lead, Mercury, Selenium, Manganese in blood are positively correlated with hypertension, while Cadmium in blood is negatively correlated with hypertension.


Assuntos
Compostos de Cálcio , Hipertensão , Mercúrio , Metais Pesados , Óxidos , Selênio , Humanos , Cádmio/urina , Inquéritos Nutricionais , Antimônio/urina , Manganês , Tálio/urina , Tungstênio/urina , Bário/urina , Estanho , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Metais Pesados/efeitos adversos , Metais Pesados/urina , Aprendizado de Máquina
17.
Chemosphere ; 351: 141128, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38185424

RESUMO

Photocatalytic water purification has been extensively explored for its economic, eco-friendly, and sustainable aspects. In this study, tungsten (W) incorporated BaSn1-xWxO3 (x = 0 to 0.05) nanoparticles synthesized by facile hydrogen peroxide precipitation route has been demonstrated for photocatalytic degradation of methylene blue (MB) dye and ciprofloxacin (CIP) antibiotic. The structural analysis indicates the presence of hybrid composite-like nanostructures with reduced crystallinity. Optical studies reveal blueshift in bandgap and decrease in oxygen vacancy defects upon W-incorporation. Pure BaSnO3 shows overall enhanced photocatalytic activity towards MB (90.22%) and CIP (78.12%) after 240 min of white LED light and sunlight irradiation respectively. The 2 % W-incorporated BaSnO3 shows superior photocatalytic degradation of MB (26.89%) and CIP (45.14%) within first 30 min of irradiation confirming the presence of W to be beneficial in the process. The free radical study revealed the dominant role of reactive hole (h+) and oxygen radical (O2•-) species during photodegradation and their intermediates are investigated to elucidate the degradation mechanism of MB within 30 min of irradiation. This study is promising towards developing defect mediated and time-efficient photocatalysts for environmental remediation.


Assuntos
Compostos de Cálcio , Ciprofloxacina , Nanopartículas , Óxidos , Titânio , Ciprofloxacina/química , Azul de Metileno/química , Tungstênio/química , Nanopartículas/química
18.
Zhonghua Yan Ke Za Zhi ; 60(2): 180-184, 2024 Feb 11.
Artigo em Chinês | MEDLINE | ID: mdl-38296324

RESUMO

Different from classical autosomal recessive Wolfram syndrome, Wolfram-like syndrome is an autosomal dominant disorder caused by a heterozygous mutation in the WFS1 gene. In this case, a 7-year-old male child presented to the eye clinic due to vision loss that could not be corrected, discovered during a routine examination. The child had experienced hearing impairment since early childhood, leading to cochlear implantation. Ophthalmic examination revealed optic disc atrophy in both eyes. Optical coherence tomography imaging demonstrated a distinctive thickening of the outer plexiform layer with abnormal layering, characteristic of a single mutation in the WFS1 gene. Subsequent genetic testing identified a de novo heterozygous missense mutation c.2051C>T (p.A684V) in the WFS1 gene, which ultimately led to the diagnosis of Wolfram-like syndrome.


Assuntos
Atrofia Óptica , Síndrome de Wolfram , Criança , Humanos , Masculino , Mutação , Atrofia Óptica/genética , Linhagem , Tungstênio , Síndrome de Wolfram/genética , Síndrome de Wolfram/diagnóstico
19.
Colloids Surf B Biointerfaces ; 234: 113742, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38271855

RESUMO

Because of the excellent performance in photochemistry, WO3 is increasingly applied in the field of biology and medicine. However, little is known about the mechanism of WO3 cytotoxicity. In this work, WO3 nanosheets with oxygen vacancy are synthesized by solvothermal method, then characterized and added to culture medium of human umbilical vein endothelial cells (HUVECs) with different concentrations. We characterized and analyzed the morphology of nano-WO3 by transmission electron microscopy and calculated the specific data of oxygen vacancy by XPS. It is the first time the effect of WO3-x on cells that WO3-x can cause oxidative stress in HUVEC cells, resulting in DNA damage and thus promoting apoptosis. Transcriptome sequencing is performed on cells treated with low and high concentrations of WO3-x, and a series of key signals affecting cell proliferation and apoptosis are detected in differentially expressed genes, which indicates the research direction of nanotoxicity. The expression levels of key genes are also verified by quantitative PCR after cell treatment with different concentrations of WO3-x. This work fills the gap between the biocompatibility of nano WO3-x materials and molecular cytology and paves the way for investigating the mechanism and risks of oxygen vacancy in cancer therapy.


Assuntos
Óxidos , Oxigênio , Humanos , Células Endoteliais da Veia Umbilical Humana , Óxidos/química , Tungstênio/toxicidade , Tungstênio/química
20.
J Appl Clin Med Phys ; 25(3): e14225, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38213084

RESUMO

PURPOSE: A well-known limitation of multi-leaf collimators is that they cannot easily form island blocks. This can be important in mantle region therapy. Cerrobend photon blocks, currently used for supplementary shielding, are labor-intensive and error-prone. To address this, an innovative, non-toxic, automatically manufactured photon block using 3D-printing technology is proposed, offering a patient-specific and accurate alternative. METHODS AND MATERIALS: The study investigates the development of patient-specific photon shielding blocks using 3D-printing for three different patient cases. A 3D-printed photon block shell filled with tungsten ball bearings (BBs) was designed to have similar dosimetric properties to Cerrobend standards. The generation of the blocks was automated using the Eclipse Scripting API and Python. Quality assurance was performed by comparing the expected and actual weight of the tungsten BBs used for shielding. Dosimetric and field geometry comparisons were conducted between 3D-printed and Cerrobend blocks, utilizing ionization chambers, imaging, and field geometry analysis. RESULTS: The quality assurance assessment revealed a -1.3% average difference in the mass of tungsten ball bearings for different patients. Relative dose output measurements for three patient-specific blocks in the blocked region agreed within 2% of each other. Against the Treatment Planning System (TPS), both 3D-printed and Cerrobend blocks agreed within 2%. For each patient, 6 MV image profiles taken through the 3D-printed and Cerrobend blocks agreed within 1% outside high gradient regions. Jaccard distance analysis of the MV images against the TPS planned images, found Cerrobend blocks to have 15.7% dissimilarity to the TPS, while that of the 3D-printed blocks was 6.7%. CONCLUSIONS: This study validates a novel, efficient 3D-printing method for photon block creation in clinical settings. Despite potential limitations, the benefits include reduced manual labor, automated processes, and greater precision. It holds potential for widespread adoption in radiation therapy, furthering non-toxic radiation shielding.


Assuntos
Proteção Radiológica , Tungstênio , Humanos , Fótons , Radiometria , Impressão Tridimensional , Planejamento da Radioterapia Assistida por Computador , Dosagem Radioterapêutica
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