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1.
J Environ Sci (China) ; 149: 394-405, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181652

RESUMO

Heterogeneous crystallization is a common occurrence during the formation of solid wastes. It leads to the encapsulation of valuable/hazardous metals within the primary phase, presenting significant challenges for waste treatment and metal recovery. Herein, we proposed a novel method involving the in-situ formation of a competitive substrate during the precipitation of jarosite waste, which is an essential process for removing iron in zinc hydrometallurgy. We observed that the in-situ-formed competitive substrate effectively inhibits the heterogeneous crystallization of jarosite on the surface of anglesite, a lead-rich phase present in the jarosite waste. As a result, the iron content on the anglesite surface decreases from 34.8% to 1.65%. The competitive substrate was identified as schwertmannite, characterized by its loose structure and large surface area. Furthermore, we have elucidated a novel mechanism underlying this inhibition of heterogeneous crystallization, which involves the local supersaturation of jarosite caused by the release of ferric and sulfate ions from the competitive substrate. The local supersaturation promotes the preferential heterogeneous crystallization of jarosite on the competitive substrate. Interestingly, during the formation of jarosite, the competitive substrate gradually vanished through a dissolution-recrystallization process following the Ostwald rule, where a metastable phase slowly transitions to a stable phase. This effectively precluded the introduction of impurities and reduced waste volume. The goal of this study is to provide fresh insights into the mechanism of heterogeneous crystallization control, and to offer practical crystallization strategies conducive to metal separation and recovery from solid waste in industries.


Assuntos
Cristalização , Compostos Férricos , Compostos Férricos/química , Sulfatos/química , Compostos de Ferro/química , Ferro/química , Eliminação de Resíduos/métodos
2.
Sci Rep ; 14(1): 20894, 2024 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-39245771

RESUMO

This study proposes an innovative approach to combat the escalating threat of antibiotic resistance in bacteria by introducing a novel ZnO-propolis nanocomposite (ZnO-P NCs). The overuse of antibiotics, particularly during events like the COVID-19 pandemic, has intensified bacterial resistance, necessitating innovative solutions. The study employs a cost-effective and controllable biosynthesis method to produce ZnO nanoparticles (ZnO-NPs), with propolis extract crucially contributing to the reduction and stabilization of Zn2+ ions. A biodegradable nano-propolis matrix is then created by incorporating ZnO-NPs, forming the ZnO-P NCs. Structural stability is confirmed through FT-IR and Zeta potential analysis, while nanoscale properties are validated via TEM, SEM, and XRD analyses. The antimicrobial efficacy of various substances, including propolis, nano propolis, ethanolic propolis extract, ZnO-NPs, and ZnO-P NCs, is assessed against Gram-negative and Gram-positive bacteria, alongside a comparison with 28 antibiotics. Among the bacteria tested, Pseudomonas aeruginosa PAO1 ATCC15692 was more sensitive (40 mm) to the biosynthesized nanocomposite ZnO-P NCs than to ZnO-NPs (38 mm) and nanopropolis (32 mm), while Escherichia coli was resistant to nanopropolis (0 mm) than to ZnO-NPs (31 mm), and ZnO-P NCs (34 mm). The study reveals a synergy effect when combining propolis with green-synthesized ZnO-NPs in the form of ZnO-P NCs, significantly improving their efficiency against all tested bacteria, including antibiotic-resistant strains like E. coli. The nanocomposite outperforms other materials and antibiotics, demonstrating remarkable antibacterial effectiveness. SEM imaging confirms the disruption of bacterial cell membranes by ZnO-NPs and ZnO-P NCs. The study emphasizes the potential applications of ZnO-NPs integrated into biodegradable materials and underscores the significance of the zinc oxide-propolis nanocomposite in countering antimicrobial resistance. Overall, this research offers a comprehensive solution to combat multidrug-resistant bacteria, opening avenues for novel approaches in infection control.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Nanocompostos , Própole , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Própole/química , Própole/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas Metálicas/química
3.
Anal Biochem ; 696: 115661, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39251155

RESUMO

Invertase enzyme can effectively improve the taste, color, and durability of these products. Various methods have been proposed to increase the stability and efficiency of enzymes. One of the most important is enzyme immobilization, which can be implemented on different materials. The purpose of this study was to immobilize the invertase enzyme on the surface of green synthesized zinc oxide nanoparticles and to investigate its biochemical properties. The enzyme immobilization was confirmed by SEM and Raman spectroscopy. Then, the biochemical characteristics, such as optimal pH and temperature, thermal stability, and storage stability of free and immobilized enzymes, were determined. The results of SEM showed that the diameter of synthesized nanoparticles was about 60 ± 5 nm. FTIR of immobilized invertase confirmed the immobilization process. The immobilization efficiency was determined to be 72 %. Immobilized enzyme showed higher thermal stability at 40 and 50 °C. Immobilized enzyme could be used 8 times in optimum condition. Also, an Examination of the kinetic parameters of the immobilized enzyme compared with those of the free enzyme showed a decrease in the maximum velocity of the enzyme. It seems that the immobilized invertase has improved characteristics for application in different industries.

4.
Chem Asian J ; : e202400828, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39231000

RESUMO

Aqueous zinc-ion batteries (AZIBs) are a potential new technology in energy storage due to their high energy density, affordability, and environmental friendliness. Unchecked zinc dendrite formation during cycling still hinders the development of AZIBs, resulting in an unstable interface, a short cycling life, a considerable capacity decline, and security issues. Herein, we demonstrate a novel nanofiber membrane based on a polyethylenimine-polyacrylonitrile (PEI-PAN) polymer produced by electrospinning with entangled nanofibers for AZIBs applications. The as-fabricated PEI/PAN membrane has a porous structure that is homogeneous, tortuous, and linked, with high porosity and superior electrolyte wettability. The PEI/PAN membrane has good thermal stability at 200 °C and high ionic conductivity of up to 5.3 x 10-4 S cm-1. This membrane provides Zn/Zn symmetric cells with an ultralong cycle life of over 250 hours at 3 mA cm-2. Additionally, MnO2/Zn cells outperforms commercial filter paper in terms of cycle stability and rate performance. This work demonstrates a simple technique for fabricating advanced nanofiber membranes for AZIBs to modify Zn2+ deposition behavior and improve Zn dendrite resistance.

5.
Front Immunol ; 15: 1425351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39229277

RESUMO

Background: Micronutrients play pivotal roles in modulating various aspects of the immune response. However, the existing literature on the association between micronutrients and autoimmune thyroiditis (AIT) remains limited and contentious. To address this gap, we conducted Mendelian randomization (MR) to investigate potential links between genetically predicted concentrations of six micronutrients (Copper (Cu), Iron (Ir), Calcium (Ca), Vitamin D (VD), Vitamin C (VC), Zinc (Zn)) and the risk of AIT. Method: Utilizing summary statistics from genome-wide association studies (GWAS) in individuals of European descent, we employed MR methodologies to elucidate the interplay between micronutrients and AIT. Three distinct MR techniques were employed: Inverse Variance Weighted (IVW), MR-Egger regression, and Weighted Median Estimator (WME). Additionally, we evaluated outcome heterogeneity using Cochran's Q statistic and assessed pleiotropy using the MR-Egger intercept. Result: IVW analysis revealed no substantial evidence supporting a significant impact of genetically predicted micronutrient concentrations on AIT risk (Cu: OR = 0.918, P = 0.875; Ir: OR = 0.653, P = 0.264; Ca: OR = 0.964, P = 0.906; VD: OR = 0.717, P = 0.378; VC: OR = 0.986, P = 0.875; Zn: OR = 0.789, P = 0.539). Cochran's Q test for IVW indicated no notable heterogeneity. Moreover, the MR-Egger intercept method suggested the presence of horizontal pleiotropy between serum VC levels and AIT (MR-Egger intercept = -0.037, p = 0.026), while no such pleiotropy was observed for other micronutrients. Conclusion: Our MR analysis does not support a causal relationship between genetically predicted concentrations of six micronutrients (Cu, Ir, Ca, VD, VC, and Zn) and the risk of AIT.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Micronutrientes , Tireoidite Autoimune , Humanos , Micronutrientes/sangue , Tireoidite Autoimune/genética , Tireoidite Autoimune/sangue , Fatores de Risco , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Zinco/sangue
6.
J Orthop Translat ; 48: 146-155, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39229332

RESUMO

Background: Long-term physical inactivity probably leads to a co-existence of osteoporosis and sarcopenia which result in a high risk of falls, fractures, disability and even mortality. However, universally applicable and feasible approaches are lacking in the concurrent treatment of osteoporosis and sarcopenia. In this study, we evaluated the effect of strontium zinc silicate bioceramic (SZS) extract on osteoporosis and sarcopenia and explored its underlying mechanisms. Methods: Hindlimb osteoporosis and sarcopenia were established in a tail-suspended rat model. The bones were conducted µCT scanning, histological examination, and gene expression analysis, and the muscles were conducted histological examination and gene expression analysis. In vitro, the effect of SZS extract on osteoblasts was determined by alizarin red S staining, immunofluorescence and qPCR. Similarly, the effect of SZS extract on myoblasts was determined by immunofluorescence and qPCR.. At last, the role of Piezo1 and the change of intracellular calcium ion (Ca2+) were explored through blockading the Piezo1 by GsMTx4 in MC3T3-E1 and C2C12 cells, respectively. Results: We found that SZS extract could concurrently and efficiently prevent bone structure deterioration, muscle atrophy and fibrosis in hind limbs of the tail-suspended rats. The in vivo study also showed that SZS extract could upregulate the mRNA expression of Piezo1, thereby maintaining the homeostasis of bones and muscles. In vitro study demonstrated that SZS extract could promote the proliferation and differentiation of MC3T3-E1 and C2C12 cells by increasing the intracellular Ca2+ in a Piezo1-dependent manner. Conclusion: This study demonstrated that SZS extract could increase Piezo1-mediated intracellular Ca2+, and facilitate osteogenic differentiation of osteoblast and myogenic differentiation of myoblasts, contributing to alleviation of osteoporosis and sarcopenia in a tail-suspended rat model. The translational potential of this article: The current study might provide a universally applicable and efficient strategy to treat musculoskeletal disorders based on bioactive ceramics. The verification of the role of Piezo1-modulated intracellular Ca2+ during osteogenesis and myogenesis provided a possible therapeutic target against mechanical related diseases.

7.
Comput Struct Biotechnol J ; 23: 3132-3142, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39229336

RESUMO

Trypsin inhibitors are known to act against insect pests by inhibiting proteases of the digestive tract. In this study, we report structural and functional characterization of ∼ 19 kDa Albizia procera Kunitz-type trypsin inhibitor (ApKTI) protein with potential bio-insecticidal applications. Crystal structure of ApKTI protein has been refined to 1.42 Å and molecular structure (8HNR) showed highly beta sheeted conformation including 12 beta sheets, 15 loops and two small alpha helices. Docking between predicted model of Tribolium castaneum trypsin (TcPT) and 8HNR produced a stable complex (-11.3 kcal/mol) which reflects the inhibitory potential of ApKTI against insect gut trypsin. Significant mortality was observed in all life stages of T. castaneum including egg, larvae, pupae and adults with a 3.0 mg native ApKTI treatment in comparison to negative control. Although standard trypsin inhibitor (Glycine max trypsin inhibitors; GmKTI; 3.0 mg) produced maximum reduction against all above life stages; however, a non-significant mortality difference was observed in comparison to 3.0 mg native ApKTI. The study further explores the synthesis and characterization of Graphene (GNPs) and Zinc oxide (ZnONPs) nanoparticles, followed by the optimization of ApKTI and GmKTI loading on both nanoparticles to evaluate their enhanced insecticidal effectiveness. Encapsulated proteins showed significant mortality against T. castaneum across all concentrations, with GNPs proving more effective than ZnONPs. Additionally, encapsulated GmKTI produced significant mortality of eggs compared to loaded ApKTI treatments while other life stages were non-significantly affected by two proteins. This research highlights the importance of encapsulated ApKTI protein for eco-friendly pest management strategies.

8.
Chempluschem ; : e202400382, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39255446

RESUMO

We present the synthesis, structural characterization, and reactivity studies of a tetra-zinc complex supported by the bisphenoxymethanone ligands and its transformation into various di-zinc architectures. Our findings highlight the potential of these complexes in molecular recognition, supramolecular chemistry, and catalysis.

9.
J Trace Elem Med Biol ; 86: 127519, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39255533

RESUMO

BACKGROUND: This study delves into the understudied yet potentially crucial role of paternal zinc deficiency in programming offspring metabolic outcomes. By examining paternal zinc deficiency, we aim to shed light on a previously unexplored avenue with the potential to significantly impact future generations. We investigated the intergenerational effects of paternal zinc deficiency on metabolic parameters in Drosophila melanogaster. METHODS: Dietary zinc deficiency was induced by supplementing the diet of Drosophila F0 male flies with TPEN (N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine) from egg stage. The F0 male flies after eclosion were mated with age-matched virgin female flies from the control group, resulting in the F1 offspring generation. The F1 generation were then cultured on a standard diet for subsequent metabolic analyses, including assessments of body weight, locomotion, and levels of glucose, trehalose, glycogen, and triglycerides as well as the expression of related genes. RESULTS: We observed an increase (p<0.05) in body weight in male parent flies and female offspring. Negative geotaxis performance was also impaired in the female offspring. Paternal zinc deficiency exerted distinct effects on carbohydrate and lipid metabolism, as evidenced by a significant (p<0.05) increase in trehalose and triglyceride levels in both parent and offspring. Additionally, zinc deficiency led to alterations in the expression of key metabolic genes, including significant (p<0.05) increase in DILP2 mRNA levels, highlighting potential links to insulin signaling. Also, there were reduced mRNA levels of SOD1 and CAT in both parental and offspring generations. Parental zinc deficiency also increased the expression of Eiger and UPD2 mRNA in the offspring, suggesting potential perturbations in the immune response system. CONCLUSION: These findings underscore the link between zinc status and various physiological and molecular processes, revealing both immediate and intergenerational impacts on metabolic, antioxidant, and inflammatory pathways and providing valuable insights on the implications of paternal zinc deficiency in Drosophila melanogaster.

10.
J Environ Manage ; 370: 122350, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39255574

RESUMO

The feasibility of microalgae-based biofuel production is still unclear due to the high cost and energy consumption. In order to be competitive with traditional fuels, the price per unit biofuel produced should be reduced by improving microalgal cells quality for higher biofuels productivity as well as enhancing microalgae other advantages such as wastewater treatment (WWT) and CO2 bio-fixation. In this research, the synergistic effect of iron (Fe) and zinc (Zn) addition to municipal wastewater (MWW) on Chlorella sorokiniana Pa.91 performance was investigated in terms of biomass productivity, WWT, bio-products generation and biofuel quality. According to the result, maximum biomass concentration of 1.1, 1.49, 1.36 and 1.9 mg/L were achieved after 10 days C. sorokiniana cultivation in MWW before and after addition of Fe (9 mg/L), Zn (1 mg/L) and combined Zn/Fe (6/0.5 mg/L), respectively. It was observed that the nutrients uptake ability of microalgal cells improved by pre-treatment with Fe/Zn, as the mass balance of COD, NH4 and PO43- increased from 104.5, 13.6 and 2.9 to 111.6, 16.6 and 3.78 mg per 1 g C. sorokiniana, respectively. By adding Fe/Zn, the lipid content increased from 25 to 33 % CDW, while, no significant changes were observed in the protein and carbohydrate content. The results revealed that the fatty acid composition (i.e. SFA and MUFA content) and biofuel quality of C. sorokiniana remarkability enhanced after Fe/Zn supplementation. Overall, our finding suggested that MWW enrichment with combined Fe and Zn at an appropriate dosage is a promising approach for improving microalgae performance in particular increasing biofuel production quantity and quality.

11.
ChemSusChem ; : e202401612, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256163

RESUMO

Rechargeable nickel-zinc (Ni-Zn) batteries hold great promise for large-scale applications due to their relatively high voltage, cost-efficient zinc anode, and good safety. However, the commonly used cathode materials are susceptible to overcharging and experience irreversible capacity degradation, primarily as a result of low electrical conductivity and substantial limitations in volume-constrained proton diffusion. Here, we present a robust methodology for synthesizing hierarchical nickel-cobalt (Ni-Co) hydroxides characterized by hollow interiors and interconnected nanosheet shells with the help of in situ formed metal-organic frameworks (MOFs). The templating effect of the MOF induced the hierarchical structure, while the chemical etching of MOFs by Ni2+ ions resulted in a hollow structure, thereby enhancing the surface area. Theoretical calculations suggested that incorporation of cobalt reduces the band gap, thereby improving electronic conductivity, and lowered the deprotonation energy, which mitigated overcharge issues. These advantages conferred improved specific capacity, rate capability, and cyclic stability to the Ni-Co hydroxide. The Ni-Zn cell delivered specific energy values of 338 Wh kg-1 at 1.62 kW kg-1 and 142 Wh kg-1 at 29.89 kW kg-1. Our investigations undercoreed the critical role of MOFs as intermediates in the preparation of multi-component hydroxide and the construction of hiearchical structures to achieve superior performance.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39257138

RESUMO

AIM: The objective of this Multicentric Post-Marketing Surveillance (PMS) study was to evaluate the safety and tolerance of vitamin C and zinc tablets in the Indian population experiencing deficiencies of these nutrients. Furthermore, the study aimed to provide insights into physicians' prescription practices and characterise the patient population receiving the study medication. METHODS: This prospective observational study involved 358 participants from 8 study sites across India (including 2 government hospital sites), spanning a duration of approximately 12 weeks (3 months). The primary aim was to evaluate the safety and tolerability of zinc and ascorbic acid effervescent tablets for those who were deficient in zinc and vitamin C. Throughout the study period, adverse events were monitored and categorised by MedDRA Primary System Organ Class and Preferred Term. The analysis included evaluating the incidence, percentage, and correlation of adverse events with the treatment (safety population). Additionally, the frequencies of adverse drug reactions were examined across all enrolled patients. Vital signs and symptom-focused physical examinations were conducted during each visit in the safety population. RESULTS: Out of 358 (100%) patients, only 12 (3.35%) experienced minor symptoms in the study period. The majority of patients reported gastrointestinal disorders, i.e., two (0.6%) patients reported constipation and gastritis, respectively. Diarrhoea was reported by four (1.1%) patients. One (0.3%) patient reported gastrointestinal pain. Three (0.8%) patients reported vomiting. Diarrhoea was the most common symptom reported. All patients possess a mild intensity of adverse drug reactions in safety populations. The P-value is less than 0.05 (p-value < 0.05), and therefore there is a statistically significant relationship between the predictor variables and the response variable (i.e., the expected count of adverse drug reactions). CONCLUSION: The fixed-dose combination of vitamin C and zinc effervescent tablets appears to be safe and tolerable for the treatment of vitamin C and zinc deficiencies in Indian patients. The favorable outcome underscores the mild nature of the adverse reactions and the right medical interventions and support.

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13.
Sci Total Environ ; 952: 175991, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39236814

RESUMO

BACKGROUND: People are exposed to metals in various ways during their daily lives. However, the association between metal exposure and gallstones remains unclear. OBJECTIVES: To investigate the relationship between serum elemental concentrations and the risk of gallstones. METHODS: Participants (n = 4204) were drawn from the Henan Rural Cohort. Gallstone diagnosis was based on abdominal ultrasound reports during follow-up. Baseline serum elemental concentrations were measured using inductively coupled plasma mass spectrometry. The relationship between serum elemental levels and gallstones was evaluated using robust Poisson regression, restricted cubic spline (RCS), quantile g-computation (Qgcomp), grouped weighted quantile sum (GWQS) and Bayesian kernel machine regression (BKMR). RESULTS: 121 individuals were diagnosed with gallstone (incidence rate of 2.88 %). In robust Poisson regression, after adjusting for confounding factors, the highest quartile of arsenic concentration compared to the lowest quartile had a 1.90 times higher relative risk (RR) [95 % confidence interval (CI): 1.05, 3.44]. Conversely, the highest quartile of zinc concentration compared to the lowest quartile had a 0.50 times lower RR (95 % CI: 0.28, 0.89). RCS showed an approximately "S"-shaped nonlinear relationship between serum arsenic levels and gallstones, with increasing arsenic concentration leading to a higher risk of gallstones; however, the risk plateaued when arsenic concentration exceeded 0.62 µg/L. Both the Qgcomp and GWQS indicated that arsenic plays a significant role in increasing the risk of gallstones, whereas zinc plays a significant role in reducing the risk of gallstones. BKMR showed that raising arsenic exposure from the 25th to the 75th percentile increased the risk of gallstones, while raising serum zinc concentration reduced it. CONCLUSIONS: Higher serum arsenic concentration increases the risk of gallstones, whereas higher zinc concentration may reduce the risk. Effective prevention of gallstones may require further reduction of arsenic exposure and appropriate increases in zinc intake.

14.
J Chromatogr A ; 1735: 465331, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39241403

RESUMO

Understanding the mechanism of toxicity of nanoparticles and their behavior in biological environments is crucial for designing materials with reduced side effects and improved performance. Among the factors influencing nanoparticle behavior in biological environments, the release and bioavailability of potentially toxic metal ions can alter equilibria and cause adverse effects. In this study, we applied two on-line Field-Flow Fractionation (FFF) strategies and compared the results with off-line benchmarking centrifugal ultrafiltration to assess a key descriptor, namely the solubility of zinc oxide (ZnO) nanoparticles. We found that, at the highest nanoparticle concentrations, the nanoparticle-ion ratio quickly reaches equilibrium, and the stability is not significantly affected by the separation technique. However, at lower concentrations, dynamic, non-equilibrium behavior occurs, and the results depend on the method used to separate the solid from the ionic fraction, where FFF yielded a more representative dissolution pattern. To support the (eco)toxicological profiling of the investigated nanoparticles, we generated experimental data on colloidal stability over typical (eco)toxicological assay durations. The Zeta Potential vs pH curves revealed two distinct scenarios typical of surfaces that have undergone significant modification, most likely due to pH-dependent dissolution and re-precipitation of surface groups. Finally, to enhance hazard assessment screening, we investigated ion-dependent toxicity and the effects of exposure to fresh water. Using an in vitro human skin model, we evaluated the cytotoxicity of fresh and aged ZnO nanoparticles (exposed for 72 h in M7), revealing time-dependent, dose-dependent, and nanoparticle-dependent cytotoxicity, with lower toxicity observed in the case of aged samples.

15.
J Colloid Interface Sci ; 678(Pt B): 76-87, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39241449

RESUMO

Aqueous zinc-ion batteries (AZIBs) have garnered attention from researchers for their high theoretical capacity, safety, and low cost. However, the uncontrolled growth of zinc (Zn) dendrites and spontaneous corrosion reactions on the Zn anode significantly compromise the cycle life of AZIBs. This paper proposes the utilization of a novel zeolitic imidazole framework (ZIF-N) material with zincophilicity and hydrophilicity for modifying the Zn anode of AZIBs. ZIF-N incorporates numerous electron-withdrawing nitro groups at the Zn/ZIF-N interface to regulate the uneven electron distribution on the Zn anode. The modified Zn anode (Zn@ZIF-N) exhibits a lower polarization ratio (32.18 mV at 4 mA cm-2) and an extended cycle life (over 700 h at 4 mA cm-2). At a current density of 1 mA cm-2, the battery composed of a Zn@ZIF-N anode and NVO (NaV3O8) achieves a cycle life of 1600 cycles. This work provides a straightforward and cost-effective strategy for modifying the Zn anode to prolong the cycle life of AZIBs.

16.
J Colloid Interface Sci ; 678(Pt B): 95-104, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39241451

RESUMO

The intercalation of organic molecules is a promising approach to modulate the structure of 2D transition metal borides (MBenes), aiming to enhance charge transport and improve electrochemical performance in energy storage applications. However, key questions remain regarding how organic molecules with diverse functionalities penetrate and align between the MBene layer, as well as the mechanism of charge redistribution during intercalation. Addressing these questions is crucial for guiding the design of Organic-MBene heterostructures. To this end, a comprehensive approach combining theoretical calculations and experimental analyses was employed to explore the self-assembly mechanisms of organic molecules featuring N, O, S and tertiary amine end groups on the MoB-MBene surface. Experimental characterizations confirm that the interaction between MoB and organic compounds depends on the end groups. First principles calculations demonstrate that organic molecules tend to adopt a flat configuration on the MoB surface during molecular assembly. Calculations also reveal that the binding and charge transfer processes from organic molecules to MoB are highly dependent on the specific end groups, consistent with experimental observations. Furthermore, the effect of combining organic molecules with MoB on battery performance was further discussed, offering new insights for advancing the research and development of MBenes in aqueous battery systems.

17.
Braz J Otorhinolaryngol ; 90(6): 101496, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39243697

RESUMO

OBJECTIVES: Upper respiratory tract infections, including COVID-19, are associated with olfactory dysfunction and there is a need for novel therapeutic approaches. The aim of study was evaluating the effectiveness of adding melatonin, multivitamin and sodium citrate to olfactory training for the treatment of olfactory loss caused by COVID-19. METHODS: We evaluated olfactory function using University of Pennsylvania Smell Identification Test (UPSIT ®) scores and self-reported patient outcomes in post-infectious smell loss cases. We investigated the effectiveness involved olfactory training combined with sodium citrate, melatonin, and multivitamin supplements with zinc over a three-month period compared to an olfactory training alone. RESULTS: A total of 66 patients were included, with 33 in each group. There was no significant difference in the proportion of participants who showed improvement in UPSIT scores between the groups (OR = 1.43, 95% CI 0.43-4.8, p =  0.56). Both groups showed improvement in average test scores, but there were no significant differences in self-reported olfactory ability or discomfort with olfactory loss. Qualitative symptoms, such as parosmia and phantosmia, were reported by a similar proportion in both groups before and after the treatment (p =  0.11, p =  1, respectively). CONCLUSIONS: Olfactory training alone and olfactory training with associated with melatonin, multivitamins and topical sodium citrate did not show significant differences in improving olfactory function in post-COVID-19 patients.

18.
J Colloid Interface Sci ; 678(Pt B): 162-173, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39243717

RESUMO

Designing and developing efficient, low-cost bi-functional oxygen electrocatalysts is essential for effective zinc-air batteries. In this study, we propose a copper dual-doping strategy, which involves doping both porous carbon nanofibers (PCNFs) and nickel fluoride nanoparticles with copper alone, successfully preparing copper-doped nickel fluoride (NiF2) nanorods and copper nanoparticles co-modified PCNFs (Cu@NiF2/Cu-PCNFs) as an efficient bi-functional oxygen electrocatalyst. When copper is doped into the PCNFs in the form of metallic nanoparticles, the doped elemental copper can improve the electronic conductivity of composite materials to accelerate electron conduction. Meanwhile, the copper doping for NiF2 can significantly promote the transformation of nickel fluoride nanoparticles into nanorod structures, thus increasing the electrochemical active surface area and enhancing mass diffusion. The Cu-doped NiF2 nanorods also possess an optimized electronic structure, including a more negative d-band center, smaller bandgap width and lower reaction energy barrier. Under the synergistic effect of these advantages, the obtained Cu@NiF2/Cu-PCNFs exhibit outstanding bi-functional catalytic performances, with a low overpotential of 0.68 V and a peak power density of 222 mW cm-2 in zinc-air batteries (ZABs) and stable cycling for 800 h. This work proposes a one-step way based on the dual-doping strategy, providing important guidance for designing and developing efficient catalysts with well-designed architectures for high-performance ZABs.

19.
BMC Res Notes ; 17(1): 254, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39252082

RESUMO

INTRODUCTION: Zinc with oral re-hydration salt supplementation provides much improved outcomes for managing childhood diarrhea. There is scarcity of evidence in the study area regarding zinc supplementation adherence and factors associated with. Thus, the aim of this study was to assess zinc supplementation adherence and associated factors among caregivers of under five children with diarrhea attending health centers in Gondar City. METHODS: An institutional based cross-sectional study was conducted with 405 caregivers of under-five children with diarrhea who received zinc supplementation in Gondar City health centers. Bivariable and multivariable logistic regression analysis were computed. RESULTS: 35% (95% CI: 29.91, 39.21) of caregivers of under five children adhered for zinc supplementation. Adherence was observed among caregivers with good knowledge about zinc supplementation (AOR = 3.01 95%CI = 1.73, 5.24), and who received counseling (AOR = 8.4, 95%CI = 4.66, 15.13), presence of side effects (AOR = 0.35, 95% CI 0.20, 0.65) was negatively associated with zinc supplementation adherence. CONCLUSION: In the study area, more than one third of children with diarrhea were adhered to zinc supplementation. Thus, improving the knowledge of caregivers and enhancing counseling services on benefits, dosage, duration and side effects of zinc supplementation are vital to improve adherence in the area.


Assuntos
Cuidadores , Diarreia , Suplementos Nutricionais , Adesão à Medicação , Zinco , Humanos , Cuidadores/psicologia , Feminino , Masculino , Zinco/uso terapêutico , Zinco/administração & dosagem , Diarreia/tratamento farmacológico , Etiópia , Estudos Transversais , Pré-Escolar , Lactente , Adulto , Adesão à Medicação/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Adulto Jovem , Adolescente , Pessoa de Meia-Idade
20.
BMC Chem ; 18(1): 165, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39252088

RESUMO

Topical tapinarof is used to treat plaque psoriasis (a skin disease in which red and scaly patches form are appeared on some areas of the body). The goal of the current research is to establish a facile and rapid fluorimetric technique for tapinarof analysis. The approach relied on the reaction between the drug and zinc ion through metal complexation to produce a highly-fluorescent product. The fluorescence was further enhanced by adding sodium dodecyl sulfate, and it was observed at 542 nm following excitation at 497 nm. With a correlation coefficient of 0.9997, the association between emission intensity and tapinarof concentration was linear between 2.0 and 120 ng mL-1. 1.021 ng mL-1 was the quantitation limit while 0.366 ng mL-1 was the detection limit. The buffer type, pH and concentration, type of surfactant and concentration, and finally the diluting solvent were among the reaction conditions that were closely examined and it was found that the optimum conditions were obtained upon employing teorell-stenhagen buffer optimized at pH 6.0, 1.38 × 10-2 M SDS and distilled water as a solvent are the suitable choice. With great precision and reliability, the drug under study was quantified using this method in ointment formulations. The proposed method's level of greenness was assessed using two methodologies: the analytical greenness metric (AGREE) and the Green Analytical Procedure Index (GAPI), with good recovery results ensuring high efficiency of the proposed approach on analysis of ointment without any interference from additives and excipients.

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