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1.
PLoS One ; 19(7): e0306987, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38991027

RESUMO

The laboratory-scale (in-vitro) microbial fermentation based on screening of process parameters (factors) and statistical validation of parameters (responses) using regression analysis. The recent trends have shifted from full factorial design towards more complex response surface methodology designs such as Box-Behnken design, Central Composite design. Apart from the optimisation methodologies, the listed designs are not flexible enough in deducing properties of parameters in terms of class variables. Machine learning algorithms have unique visualisations for the dataset presented with appropriate learning algorithms. The classification algorithms cannot be applied on all datasets and selection of classifier is essential in this regard. To resolve this issue, factor-response relationship needs to be evaluated as dataset and subsequent preprocessing could lead to appropriate results. The aim of the current study was to investigate the data-mining accuracy on the dataset developed using in-vitro pyruvate production using organic sources for the first time. The attributes were subjected to comparative classification on various classifiers and based on accuracy, multilayer perceptron (neural network algorithm) was selected as classifier. As per the results, the model showed significant results for prediction of classes and a good fit. The learning curve developed also showed the datasets converging and were linearly separable.


Assuntos
Carbono , Fermentação , Carbono/metabolismo , Aprendizado de Máquina , Algoritmos , Ácido Pirúvico/metabolismo , Redes Neurais de Computação , Mineração de Dados/métodos
2.
Glob Chang Biol ; 30(7): e17394, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38988095

RESUMO

Water-logged peatlands store tremendous amounts of soil carbon (C) globally, accumulating C over millennia. As peatlands become disturbed by human activity, these long-term C stores are getting destabilized and ultimately released as greenhouse gases that may exacerbate climate change. Oxidation of the dissolved organic carbon (DOC) mobilized from disturbed soils to streams and canals may be one avenue for the transfer of previously stored, millennia-aged C to the atmosphere. However, it remains unknown whether aged peat-derived DOC undergoes oxidation to carbon dioxide (CO2) following disturbance. Here, we use a new approach to measure the radiocarbon content of CO2 produced from the oxidation of DOC in canals overlying peatland soils that have undergone widespread disturbance in Indonesia. This work shows for the first time that aged DOC mobilized from drained and burned peatland soils is susceptible to oxidation by both microbial respiration and photomineralization over aquatic travel times for DOC. The bulk radiocarbon age of CO2 produced during canal oxidation ranged from modern to ~1300 years before present. These ages for CO2 were most strongly influenced by canal water depth, which was proportional to the water table level where DOC is mobilized from disturbed soils to canals. Canal microbes preferentially respired older or younger organic C pools to CO2, and this may have been facilitated by the use of a small particulate organic C pool over the dissolved pool. Given that high densities of canals are generally associated with lower water tables and higher fire risk, our findings suggest that peatland areas with high canal density may be a hotspot for the loss of aged C on the landscape. Taken together, the results of this study show how and why aquatic processing of organic C on the landscape can enhance the transfer of long-term peat C stores to the atmosphere following disturbance.


Assuntos
Dióxido de Carbono , Carbono , Solo , Solo/química , Dióxido de Carbono/análise , Carbono/análise , Indonésia , Oxirredução
3.
Luminescence ; 39(7): e4828, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39004779

RESUMO

The antibiotic tetracycline can be efficiently used as medicine for the deterrence of bacterial infections in humans, animals, and plants. However, the unprecedented use of tetracycline is of great concern owing to its low biodegradability, extensive usage, and adverse impacts on the environment and water quality. In this study, a sensitive spectrofluorometric method was proposed for the direct determination of tetracycline, based on biocompatible fluorescent carbon dots (CDs). The synthesis of CDs was performed by adopting a green hydrothermal procedure from carrot juice without requiring surface passivation or outflowing any environmentally hazardous waste. X-ray diffraction analysis and transmission electron microscopy revealed amorphous spherical-shaped CDs that exhibited blue emission under blue illumination. The fabricated fluorescent probe directly detected tetracycline in the concentration range of 4.00 × 10-6 to 1.55 × 10-5 mol L-1 with an LOD of 1.33 × 10-6 mol L-1. The performance of the probe was assessed in a tap water sample, with recovery values between 80.70 and 103.60%. The method's greenness was evaluated using the Analytical Green metric approach (AGREE) and confirmed to be within the green range. The developed method is facile, rapid, cost-effective, and offers a wide linear range and satisfactory selectivity, making it potentially suitable for determining tetracycline in water applications.


Assuntos
Antibacterianos , Carbono , Daucus carota , Corantes Fluorescentes , Sucos de Frutas e Vegetais , Pontos Quânticos , Espectrometria de Fluorescência , Tetraciclina , Daucus carota/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Pontos Quânticos/química , Carbono/química , Antibacterianos/análise , Tetraciclina/análise , Sucos de Frutas e Vegetais/análise , Limite de Detecção
4.
Luminescence ; 39(7): e4826, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39004784

RESUMO

Biocompatible and highly fluorescent phosphorus, nitrogen and sulfur carbon quantum dots (P,N,S-CQDs) were synthesized using a quick and ecologically friendly process inspired from plant sources. Garlic and red lentils were utilized as natural and inexpensive sources for efficient synthesis of the carbon-based quantum dots using green microwave-irradiation, which provides an ultrafast route for carbonization of the organic biomass and subsequent fabrication of P,N,S-CQDs within only 3 min. The formed P,N,S-CQDs showed excellent blue fluorescence at λem = 412 nm when excited at 325 nm with a quantum yield up to 26.4%. These fluorescent dots were used as a nano-sensor for the determination of the commonly used antibacterial and antiprotozoal drug, metronidazole (MTR). As MTR lacked native fluorescence and prior published techniques had several limitations, the proposed methodology became increasingly relevant. This approach affords sensitive detection with a wide linear range of 0.5-100.0 µM and LOD and LOQ values of 0.14 µM and 0.42 µM, respectively. As well as, it is cost-effective and ecologically benign. The MTT test was used to evaluate the in-vitro cytotoxicity of the fabricated P,N,S-CQDs. The findings supported a minimally cytotoxic impact and good biocompatibility, which provide a future perspective for the applicability of these CQDs in biomedical applications.


Assuntos
Carbono , Corantes Fluorescentes , Alho , Metronidazol , Micro-Ondas , Pontos Quânticos , Pontos Quânticos/química , Alho/química , Carbono/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Metronidazol/análise , Metronidazol/química , Metronidazol/farmacologia , Humanos , Sobrevivência Celular/efeitos dos fármacos
5.
Glob Chang Biol ; 30(7): e17415, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39005227

RESUMO

Microplastic (MP) pollution likely affects global soil carbon (C) dynamics, yet it remains uncertain how and to what extent MP influences soil respiration. Here, we report on a global meta-analysis to determine the effects of MP pollution on the soil microbiome and CO2 emission. We found that MP pollution significantly increased the contents of soil organic C (SOC) (21%) and dissolved organic C (DOC) (12%), the activity of fluorescein diacetate hydrolase (FDAse) (10%), and microbial biomass (17%), but led to a decrease in microbial diversity (3%). In particular, increases in soil C components and microbial biomass further promote CO2 emission (25%) from soil, but with a much higher effect of MPs on these emissions than on soil C components and microbial biomass. The effect could be attributed to the opposite effects of MPs on microbial biomass vs. diversity, as soil MP accumulation recruited some functionally important bacteria and provided additional C substrates for specific heterotrophic microorganisms, while inhibiting the growth of autotrophic taxa (e.g., Chloroflexi, Cyanobacteria). This study reveals that MP pollution can increase soil CO2 emission by causing shifts in the soil microbiome. These results underscore the potential importance of plastic pollution for terrestrial C fluxes, and thus climate feedbacks.


Assuntos
Microplásticos , Microbiologia do Solo , Microplásticos/análise , Solo/química , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Poluentes do Solo/análise , Microbiota/efeitos dos fármacos , Biomassa , Carbono/análise , Carbono/metabolismo
6.
Int J Mol Sci ; 25(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39000062

RESUMO

The present work focuses on the synthesis of a vanadium nitride (VN)/carbon nanocomposite material via the thermal decomposition of vanadyl phthalocyanine (VOPC). The morphology and chemical structure of the synthesized compounds were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoemission spectroscopy (XPS). The successful syntheses of the VOPC and non-metalated phthalocyanine (H2PC) precursors were confirmed using FTIR and XRD. The VN particles present a needle-like morphology in the VN synthesized by the sol-gel method. The morphology of the VN/C composite material exhibited small clusters of VN particles. The XRD analysis of the thermally decomposed VOPC indicated a mixture of amorphous carbon and VN nanoparticles (VN(TD)) with a cubic structure in the space group FM-3M consistent with that of VN. The XPS results confirmed the presence of V(III)-N bonds in the resultant material, indicating the formation of a VN/C nanocomposite. The VN/C nanocomposite synthesized through thermal decomposition exhibited a high carbon content and a cluster-like distribution of VN particles. The VN/C nanocomposite was used as an anode material in LIBs, which delivered a specific capacity of 307 mAh g-1 after 100 cycles and an excellent Coulombic efficiency of 99.8 at the 100th cycle.


Assuntos
Carbono , Nanocompostos , Nanocompostos/química , Carbono/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Indóis/química , Vanádio/química , Compostos de Vanádio/química , Espectroscopia Fotoeletrônica
7.
Waste Manag Res ; 42(7): 509-510, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38946251
8.
Glob Chang Biol ; 30(7): e17391, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38946293

RESUMO

Heat released from soil organic carbon (SOC) decomposition (referred to as microbial heat hereafter) could alter the soil's thermal and hydrological conditions, subsequently modulate SOC decomposition and its feedback with climate. While understanding this feedback is crucial for shaping policy to achieve specific climate goal, it has not been comprehensively assessed. This study employs the ORCHIDEE-MICT model to investigate the effects of microbial heat, referred to as heating effect, focusing on their impacts on SOC accumulation, soil temperature and net primary productivity (NPP), as well as implication on land-climate feedback under two CO2 emissions scenarios (RCP2.6 and RCP8.5). The findings reveal that the microbial heat decreases soil carbon stock, predominantly in upper layers, and elevates soil temperatures, especially in deeper layers. This results in a marginal reduction in global SOC stocks due to accelerated SOC decomposition. Altered seasonal cycles of SOC decomposition and soil temperature are simulated, with the most significant temperature increase per unit of microbial heat (0.31 K J-1) occurring at around 273.15 K (median value of all grid cells where air temperature is around 273.15 K). The heating effect leads to the earlier loss of permafrost area under RCP8.5 and hinders its restoration under RCP2.6 after peak warming. Although elevated soil temperature under climate warming aligns with expectation, the anticipated accelerated SOC decomposition and large amplifying feedback on climate warming were not observed, mainly because of reduced modeled initial SOC stock and limited NPP with heating effect. These underscores the multifaceted impacts of microbial heat. Comprehensive understanding of these effects would be vital for devising effective climate change mitigation strategies in a warming world.


Assuntos
Carbono , Mudança Climática , Temperatura Alta , Solo , Solo/química , Carbono/análise , Microbiologia do Solo , Modelos Teóricos , Estações do Ano
9.
Environ Monit Assess ; 196(8): 695, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963430

RESUMO

When ecology thrives, civilization thrives, and when ecology declines, civilization declines. Based on panel data from 30 provinces in China from 2000 to 2021, this study used marginal abatement costs to estimate the co-benefits of pollution reduction and carbon reduction. Two-way fixed effect and two-stage intermediary effect models were used to evaluate the impact of digital technology on co-benefits and its indirect channels. The results indicated that China's total carbon emissions maintained a steady growth trend, while air pollution showed a fluctuating declining trend. Reaching peak carbon neutrality calls for more innovative solutions. Under joint emission reduction efforts, the study revealed marginal abatement cost savings of 535.8 million yuan/million tons and 6216.5 million yuan/µg/m3 for carbon reduction and pollution reduction, respectively. Most importantly, the study confirmed that joint emission reduction programs can reduce environmental governance costs more than individual emission reductions can, and the co-benefits increased from 37.983 to 44.757. The co-benefits generally showed a trend of fluctuation and increases and had the characteristics of phased transformation. Intragroup differences and cross-overlapping between regions made regional differences in co-benefits obvious. The subversive, permeable, and integrated features of digital technology have resulted in the all-around transformation of the economy and society, and the new technology-economy paradigm has significantly improved co-benefits. The conclusion remains valid after robustness testing and controlling for endogeneity problems. The results of the mechanism analysis suggest that digital technology can indirectly improve synergies through the intermediary channels of fostering green technology innovation, reducing energy consumption intensity and improving the energy structure.


Assuntos
Poluição do Ar , Tecnologia Digital , Monitoramento Ambiental , Poluição do Ar/prevenção & controle , Poluição do Ar/estatística & dados numéricos , China , Monitoramento Ambiental/métodos , Carbono/análise , Poluentes Atmosféricos/análise
10.
Sci Rep ; 14(1): 15114, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956155

RESUMO

Wheat straw returning is a common agronomic measure in the farmland. Understanding organic carbon transformation is of great significance for carbon budget under the premise of widespread distribution of cadmium (Cd) contaminated soils. An incubation experiment was conducted to assess the influence of Cd contamination on the decomposition and accumulation of total organic carbon (TOC) as well as the composition and abundance of bacterial communities in eight soil types with wheat straw addition. The results showed that inhibition of Cd contamination on microbially mediated organic carbon decomposition was affected by soil types. The lower cumulative C mineralization and higher TOC content could be observed in the acidic soils relative to that in the alkaline soils. The content of Cd in soil exhibits different effects on the inhibition in decomposition of TOC. The high dosage level of Cd had stronger inhibitory impact due to its high toxicity. The decomposition of TOC was restricted by a reduction in soil bacterial abundance and weakening of bacterial activities. Redundancy analysis (RDA) indicated that Proteobacteria and Gemmatimonadetes were abundant in alkaline Cd-contaminated soils with wheat straw addition, while Bacteroidetes dominated cumulative C mineralization in acidic Cd-contamination soils. Moreover, the abundance of predicted functional bacteria indicated that high-dose Cd-contamination and acid environment all inhibited the decomposition of TOC. The present study suggested that pH played an important role on carbon dynamics in the Cd-contaminated soils with wheat straw addition.


Assuntos
Cádmio , Carbono , Microbiologia do Solo , Poluentes do Solo , Solo , Triticum , Cádmio/metabolismo , Cádmio/análise , Triticum/metabolismo , Triticum/química , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Carbono/metabolismo , Carbono/análise , Solo/química , Bactérias/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio
11.
Radiat Oncol ; 19(1): 85, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956684

RESUMO

BACKGROUND: Radiotherapy is essential in the treatment of prostate cancer. An alternative to conventional photon radiotherapy is the application of carbon ions, which provide a superior intratumoral dose distribution and less induced damage to adjacent healthy tissue. A common characteristic of prostate cancer cells is their dependence on androgens which is exploited therapeutically by androgen deprivation therapy in the advanced prostate cancer stage. Here, we aimed to analyze the transcriptomic response of prostate cancer cells to irradiation by photons in comparison to carbon ions, focusing on DNA damage, DNA repair and androgen receptor signaling. METHODS: Prostate cancer cell lines LNCaP (functional TP53 and androgen receptor signaling) and DU145 (dysfunctional TP53 and androgen receptor signaling) were irradiated by photons or carbon ions and the subsequent DNA damage was assessed by immuno-cytofluorescence. Furthermore, the cells were treated with an androgen-receptor agonist. The effects of irradiation and androgen treatment on the gene regulation and the transcriptome were investigated by RT-qPCR and RNA sequencing, followed by bioinformatic analysis. RESULTS: Following photon or carbon ion irradiation, both LNCaP and DU145 cells showed a dose-dependent amount of visible DNA damage that decreased over time, indicating occurring DNA repair. In terms of gene regulation, mRNAs involved in the TP53-dependent DNA damage response were significantly upregulated by photons and carbon ions in LNCaP but not in DU145 cells, which generally showed low levels of gene regulation after irradiation. Both LNCaP and DU145 cells responded to photons and carbon ions by downregulation of genes involved in DNA repair and cell cycle, partially resembling the transcriptome response to the applied androgen receptor agonist. Neither photons nor carbon ions significantly affected canonical androgen receptor-dependent gene regulation. Furthermore, certain genes that were specifically regulated by either photon or carbon ion irradiation were identified. CONCLUSION: Photon and carbon ion irradiation showed a significant congruence in terms of induced signaling pathways and transcriptomic responses. These responses were strongly impacted by the TP53 status. Nevertheless, irradiation mode-dependent distinct gene regulations with undefined implication for radiotherapy outcome were revealed. Androgen receptor signaling and irradiations shared regulation of certain genes with respect to DNA-repair and cell-cycle.


Assuntos
Fótons , Neoplasias da Próstata , Receptores Androgênicos , Transdução de Sinais , Transcriptoma , Proteína Supressora de Tumor p53 , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Proteína Supressora de Tumor p53/metabolismo , Transcriptoma/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Dano ao DNA/efeitos da radiação , Radioterapia com Íons Pesados , Reparo do DNA , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linhagem Celular Tumoral , Carbono/farmacologia
12.
FASEB J ; 38(13): e23795, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38984928

RESUMO

Cystathionine beta-synthase-deficient homocystinuria (HCU) is a life-threatening disorder of sulfur metabolism. HCU can be treated by using betaine to lower tissue and plasma levels of homocysteine (Hcy). Here, we show that mice with severely elevated Hcy and potentially deficient in the folate species tetrahydrofolate (THF) exhibit a very limited response to betaine indicating that THF plays a critical role in treatment efficacy. Analysis of a mouse model of HCU revealed a 10-fold increase in hepatic levels of 5-methyl -THF and a 30-fold accumulation of formiminoglutamic acid, consistent with a paucity of THF. Neither of these metabolite accumulations were reversed or ameliorated by betaine treatment. Hepatic expression of the THF-generating enzyme dihydrofolate reductase (DHFR) was significantly repressed in HCU mice and expression was not increased by betaine treatment but appears to be sensitive to cellular redox status. Expression of the DHFR reaction partner thymidylate synthase was also repressed and metabolomic analysis detected widespread alteration of hepatic histidine and glutamine metabolism. Many individuals with HCU exhibit endothelial dysfunction. DHFR plays a key role in nitric oxide (NO) generation due to its role in regenerating oxidized tetrahydrobiopterin, and we observed a significant decrease in plasma NOx (NO2 + NO3) levels in HCU mice. Additional impairment of NO generation may also come from the HCU-mediated induction of the 20-hydroxyeicosatetraenoic acid generating cytochrome CYP4A. Collectively, our data shows that HCU induces dysfunctional one-carbon metabolism with the potential to both impair betaine treatment and contribute to multiple aspects of pathogenesis in this disease.


Assuntos
Homocistinúria , Fígado , Oxirredução , Tetra-Hidrofolato Desidrogenase , Tetra-Hidrofolatos , Animais , Homocistinúria/metabolismo , Homocistinúria/tratamento farmacológico , Homocistinúria/genética , Camundongos , Tetra-Hidrofolatos/metabolismo , Fígado/metabolismo , Tetra-Hidrofolato Desidrogenase/metabolismo , Tetra-Hidrofolato Desidrogenase/genética , Betaína/metabolismo , Betaína/farmacologia , Homocisteína/metabolismo , Camundongos Endogâmicos C57BL , Cistationina beta-Sintase/metabolismo , Cistationina beta-Sintase/genética , Carbono/metabolismo , Masculino , Ácido Fólico/metabolismo , Feminino
13.
PLoS One ; 19(7): e0306425, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985773

RESUMO

Global climate change has caused a series of environmental problems, green technology innovation is necessitating strategic responses, but the impact of low-carbon city pilot policy on urban green technology innovation is unclear. Based on panel data from 285 Chinese cities during 2005-2022, this study employs the Difference in Difference method to examine the impact of low-carbon city policy on urban green technology innovation. The results show that (1) The low-carbon city pilot policy promotes urban green technology innovation. (2) The low-carbon city pilot policy promotes urban green technology innovation through government green input and public engagement. (3) New infrastructure enhances the impact of low-carbon city pilot policy on quantity of green technology innovation. (4) Compared with the Yangtze River Economic Belt, the low-carbon city policy has a greater influence on urban green technology innovation in the Yellow River Basin.The findings provide policy insights for the construction of low-carbon pilot cities.


Assuntos
Carbono , Cidades , Projetos Piloto , Invenções , China , Humanos , Mudança Climática , Tecnologia , Governo
14.
Mikrochim Acta ; 191(8): 460, 2024 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987355

RESUMO

The facile sonochemical synthesis is reported of zinc cobalt oxide (ZnCo2O4) composited with carbon nanofiber (CNF). Structural, chemical, and morphological were characterized by X-ray diffraction (XRD), X-ray photoluminescent spectroscopy (XPS), field emission scanning electron microscopy (FESEM), and transmittance electron microscopy (TEM), respectively. ZnCo2O4/CNF-modified GCE was applied to the detection of bisphenol A (BPA). The modified GCE shows enhanced sensing performance towards BPA, which includes a linear range (0.2 to 120 µM L-1) alongside a low limit of detection (38.2 nM L-1), low interference, and good stability. Detection of lower concentrations of BPA enables real sample analysis in the food industries (milk, orange juice, yogurt, tap water, and baby feeding bottles). Surprisingly, the BPA was detected in milk 510 nM L-1, orange juice 340 nM L-1, yogurt 1050 nM L-1, and tap water 140 nM L-1. Moreover, an interaction mechanism between the BPA analyte and ZnCo2O4 was discussed.


Assuntos
Compostos Benzidrílicos , Carbono , Cobalto , Leite , Nanofibras , Fenóis , Compostos Benzidrílicos/análise , Fenóis/análise , Fenóis/química , Cobalto/química , Carbono/química , Leite/química , Nanofibras/química , Contaminação de Alimentos/análise , Animais , Óxidos/química , Limite de Detecção , Técnicas Eletroquímicas/métodos , Sucos de Frutas e Vegetais/análise , Química Verde/métodos , Iogurte/análise
15.
Sci Rep ; 14(1): 16112, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997319

RESUMO

In the present work, Verbena Officinalis (VO) leaf extract was used as potential corrosion inhibitor for the corrosion of carbon steel (CS) in 0.5 M H2SO4 medium. Further, the corrosion inhibiting nature of VO leaf extract towards the CS was evaluated using mass loss (ML), potentiodynamic polarization (PDP), electrical impedance spectroscopy (EIS) and surface morphological analyses using atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS) techniques. Calculation of activation energy E a ∗ using Arrhenius equation shows the increase in activation energy when adding the VO leaf extract in 0.5 M H2SO4 medium and the maximum activation energy ( E a ∗ = 49.9 kJ mol-1) was observed for 1000 mg L-1 VO leaf extract in acid medium. The negative free energy values suggested the spontaneous and the stability of the adsorbed layer of VO leaf extract on the CS surface. Using EIS measurements, high percent inhibitory effectiveness of 91.1% for 1000 ppm solutions was achieved. With an increase in VO leaf extract dose, the double layer capacitance (Cdl) values fall while the values of charge transfer (Rct) increase. This showed that a protective layer of VO leaf extract on CS surface was formed. The polarization curves showed that the VO leaf extract acts as a mixed-type inhibitor. It is discovered that the adsorption of VO leaf extract molecules adhering to the CS surface followed the Langmuir isotherm. The anti-corrosion action of VO leaf extract is fully demonstrated by some surface techniques.


Assuntos
Extratos Vegetais , Folhas de Planta , Aço , Verbena , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Aço/química , Corrosão , Verbena/química , Microscopia de Força Atômica , Espectroscopia Fotoeletrônica , Carbono/química , Concentração de Íons de Hidrogênio , Propriedades de Superfície , Espectroscopia Dielétrica
16.
J Nanobiotechnology ; 22(1): 412, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997713

RESUMO

The senescence of nucleus pulposus (NP) cells (NPCs), which is induced by the anomalous accumulation of reactive oxygen species (ROS), is a major cause of intervertebral disc degeneration (IVDD). In this research, glutathione-doped carbon dots (GSH-CDs), which are novel carbon dot antioxidant nanozymes, were successfully constructed to remove large amounts of ROS for the maintenance of NP tissue at the physical redox level. After significantly scavenging endogenous ROS via exerting antioxidant activities, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and total antioxidant capacity, GSH-CDs with good biocompatibility have been demonstrated to effectively improve mitochondrial dysfunction and rescue NPCs from senescence, catabolism, and inflammatory factors in vivo and in vitro. In vivo imaging data and histomorphological indicators, such as the disc height index (DHI) and Pfirrmann grade, demonstrated prominent improvements in the progression of IVDD after the topical application of GSH-CDs. In summary, this study investigated the GSH-CDs nanozyme, which possesses excellent potential to inhibit the senescence of NPCs with mitochondrial lesions induced by the excessive accumulation of ROS and improve the progression of IVDD, providing potential therapeutic options for clinical treatment.


Assuntos
Carbono , Glutationa , Degeneração do Disco Intervertebral , Núcleo Pulposo , Estresse Oxidativo , Espécies Reativas de Oxigênio , Degeneração do Disco Intervertebral/tratamento farmacológico , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Núcleo Pulposo/metabolismo , Núcleo Pulposo/efeitos dos fármacos , Núcleo Pulposo/patologia , Animais , Estresse Oxidativo/efeitos dos fármacos , Carbono/química , Carbono/farmacologia , Glutationa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Pontos Quânticos/química , Antioxidantes/farmacologia , Masculino , Senescência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Catalase/metabolismo , Catalase/farmacologia , Superóxido Dismutase/metabolismo
17.
ACS Appl Bio Mater ; 7(7): 4690-4701, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38952293

RESUMO

Dopamine, alongside norepinephrine and epinephrine, belongs to the catecholamine group, widely distributed across both plant and animal kingdoms. In mammals, these compounds serve as neurotransmitters with roles in glycogen mobilization. In plants, their synthesis is modulated in response to stress conditions aiding plant survival by emitting these chemicals, especially dopamine that relieves their resilience against stress caused by both abiotic and biotic factors. In present studies, there is a lack of robust methods to monitor the operations of dopamine under stress conditions or any adverse situations across the plant's developmental stages from cell to cell. In our study, we have introduced a groundbreaking approach to track dopamine generation and activity in various metabolic pathways by using the simple nitrogen and sulfur co-doped carbon quantum dots (N, S-CQDs). These CQDs exhibit dominant biocompatibility, negligible toxicity, and environmentally friendly characteristics using a quenching process for fluorometric dopamine detection. This innovative nanomarker can detect even small amounts of dopamine within plant cells, providing insights into plant responses to strain and anxiety. Confocal microscopy has been used to corroborate this occurrence and to provide visual proof of the process of binding dopamine with these N, S-CQDs inside the cells.


Assuntos
Dopamina , Pontos Quânticos , Dopamina/metabolismo , Pontos Quânticos/química , Tamanho da Partícula , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Teste de Materiais , Plantas/metabolismo , Plantas/química , Carbono/química
18.
Ecotoxicol Environ Saf ; 281: 116669, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38954908

RESUMO

In most of advanced oxidation processes (AOPs) used to destroy harmful organic chemicals in water/wastewater hydroxyl radical (•OH) reactions oxidize (increasing the oxygen/carbon ratio in the molecules) and mineralize (transforming them to inorganic molecules, H2O, CO2, etc.) these contaminants. In this paper, we used the radiolysis of water to produce •OH and characterised the rate of oxidation and mineralization by the dose dependences of the Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) content values. Analysis of the dose dependences for 34 harmful organic compounds showed large differences in the oxidation and mineralization rates and these parameters are characteristic to the given group of chemicals. E.g., the rate of oxidation is relatively low for fluoroquinolone antibiotics; it is high for ß-blocker medicines. Mineralization rates are low for both fluoroquinolones and ß-blockers. The one-electron-oxidant •OH in most cases induces two - four-electron-oxidations. Most of the degradation takes place gradually, through several stable molecule intermediates. However, based on the results it is likely, that some part of the oxidation and mineralization takes place parallel. The organic radicals formed in •OH reactions react with several O2 molecules and release several inorganic fragments during the radical life cycle.


Assuntos
Radical Hidroxila , Compostos Orgânicos , Oxirredução , Poluentes Químicos da Água , Radical Hidroxila/química , Poluentes Químicos da Água/química , Compostos Orgânicos/química , Análise da Demanda Biológica de Oxigênio , Águas Residuárias/química , Carbono/química
19.
Ecol Lett ; 27(7): e14469, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38990962

RESUMO

The decline in global plant diversity has raised concerns about its implications for carbon fixation and global greenhouse gas emissions (GGE), including carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). Therefore, we conducted a comprehensive meta-analysis of 2103 paired observations, examining GGE, soil organic carbon (SOC) and plant carbon in plant mixtures and monocultures. Our findings indicate that plant mixtures decrease soil N2O emissions by 21.4% compared to monocultures. No significant differences occurred between mixtures and monocultures for soil CO2 emissions, CH4 emissions or CH4 uptake. Plant mixtures exhibit higher SOC and plant carbon storage than monocultures. After 10 years of vegetation development, a 40% reduction in species richness decreases SOC content and plant carbon storage by 12.3% and 58.7% respectively. These findings offer insights into the intricate connections between plant diversity, soil and plant carbon storage and GGE-a critical but previously unexamined aspect of biodiversity-ecosystem functioning.


Assuntos
Biodiversidade , Carbono , Gases de Efeito Estufa , Plantas , Solo , Solo/química , Gases de Efeito Estufa/análise , Carbono/metabolismo , Carbono/análise , Plantas/metabolismo , Óxido Nitroso/análise , Óxido Nitroso/metabolismo , Ecossistema , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Metano/metabolismo , Efeito Estufa
20.
Mikrochim Acta ; 191(8): 463, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995455

RESUMO

The intensifying global opioid crisis, majorly attributed to fentanyl (FT) and its analogs, has necessitated the development of rapid and ultrasensitive remote/on-site FT sensing modalities. However, current approaches for tracking FT exposure through wastewater-based epidemiology (WBE) are unadaptable, time-consuming, and require trained professionals. Toward developing an extended in situ wastewater opioid monitoring system, we have developed a screen-printed electrochemical FT sensor and integrated it with a customized submersible remote sensing probe. The sensor composition and design have been optimized to address the challenges for extended in situ FT monitoring. Specifically, ZIF-8 metal-organic framework (MOF)-derived mesoporous carbon (MPC) nanoparticles (NPs) are incorporated in the screen-printed carbon electrode (SPCE) transducer to improve FT accumulation and its electrocatalytic oxidation. A rapid (10 s) and sensitive square wave voltammetric (SWV) FT detection down to 9.9 µgL-1 is thus achieved in aqueous buffer solution. A protective mixed-matrix membrane (MMM) has been optimized as the anti-fouling sensor coating to mitigate electrode passivation by FT oxidation products and enable long-term, intermittent FT monitoring. The unique MMM, comprising an insulating polyvinyl chloride (PVC) matrix and carboxyl-functionalized multi-walled carbon nanotubes (CNT-COOH) as semiconductive fillers, yielded highly stable FT sensor operation (> 95% normalized response) up to 10 h in domestic wastewater, and up to 4 h in untreated river water. This sensing platform enables wireless data acquisition on a smartphone via Bluetooth. Such effective remote operation of submersible opioid sensing probes could enable stricter surveillance of community water systems toward timely alerts, countermeasures, and legal enforcement.


Assuntos
Analgésicos Opioides , Técnicas Eletroquímicas , Fentanila , Estruturas Metalorgânicas , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Fentanila/análise , Fentanila/sangue , Analgésicos Opioides/análise , Estruturas Metalorgânicas/química , Eletrodos , Águas Residuárias/análise , Monitoramento Ambiental/métodos , Limite de Detecção , Carbono/química , Nanopartículas/química , Tecnologia de Sensoriamento Remoto/métodos
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