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1.
J Environ Sci (China) ; 148: 451-467, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095179

RESUMEN

After the ultralow emission transformation of coal-fired power plants, cement production became China's leading industrial emission source of nitrogen oxides. Flue gas dust contents at the outlet of cement kiln preheaters were as high as 80-100 g/m3, and the calcium oxide content in the dust exceeded 60%. Commercial V2O5(-WO3)/TiO2 catalysts suitable for coal-fired flue gas suffer from alkaline earth metal Ca poisoning of cement kiln flue gas. Recent studies have also identified the poisoning of cement kiln selective catalytic reaction (SCR) catalysts by the heavy metals lead and thallium. Investigation of the poisoning process is the primary basis for analyzing the catalytic lifetime. This review summarizes and analyzes the SCR catalytic mechanism and chronicles the research progress concerning this poisoning mechanism. Based on the catalytic and toxification mechanisms, it can be inferred that improving the anti-poisoning performance of a catalyst enhances its acidity, surface redox performance-active catalytic sites, and shell layer protection. The data provide support in guiding engineering practice and reducing operating costs of SCR plants. Finally, future research directions for SCR denitrification catalysts in the cement industry are discussed. This study provides critical support for the development and optimization of poisoning-resistant SCR denitrification catalysts.


Asunto(s)
Materiales de Construcción , Catálisis , Contaminantes Atmosféricos/química , Centrales Eléctricas , China
2.
Small ; : e2406165, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39126365

RESUMEN

The calcium looping technology employing CaO-based sorbents is pivotal for capturing CO2 from flue gas. However, the intrinsic low thermodynamic stability of CaO-based sorbents and the requisite molding step induce severe sintering issues, diminishing their cyclic stability. Herein, a high-entropy fluorite oxide (HEFO) inert stabilizer premised on entropy stabilization and synergistic effect strategies is introduced. HEFO-modified, CaO-based sorbent pellets are synthesized via a rapid cigarette butt-assisted combustion process (15 min) combined with the graphite molding method. Post-multiple cycles, their CO2 capture capacity reaches 0.373 g g-1, which is 2.6-fold superior to that of pure CaO, demonstrating markedly enhanced anti-sintering properties. First, the subtle morphological and crystallographic modifications suggest that the inherent entropy stability of HEFO imparts robust thermal resistance. Concurrently, the disordered structure of single-phase HEFO exhibits a high affinity for CaO, resulting in an interface binding energy of -1.83 eV, in sharp contrast to the -0.112 eV of pure CaO, thereby restricting CaO migration. Additionally, the multi-element synergistic effect of HEFO reduces the energy barrier by 0.15 eV, leading to a 40% and 140% increase in carbonation and calcination rates, respectively. This work presents highly efficient and rapidly synthesized CaO-based sorbent pellets, showcasing promising potential for industrial application.

3.
J Environ Manage ; 368: 122222, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39153321

RESUMEN

With the increasing demand for Li, the recovery of Li from solid waste, such as Li-containing Al electrolytes, is receiving growing attention. However, Li-containing Al electrolytes often contain large amounts of F, leading to environmental pollution. Herein, a new method for preparing water-soluble Li salt from waste Li-containing Al electrolytes with high F and Na contents is proposed based on CaO roasting and water leaching. The effects of different roasting and leaching conditions on the Li leaching efficiency and reaction pathway were systematically investigated. Under the optimum processing conditions, the Li leaching efficiency reached 98%, while those of Na and F were 98.41% and 0.24%, respectively. Phase evolution analysis showed that the addition of CaO promoted the conversion of LiF and Na2LiAlF6 to Li2O, whereas F entered the slag phase as CaF2, which could be reused as a raw material for steel refinement. Overall, this study proposes an efficient and environmentally friendly method for the treatment and resource utilization of waste Al electrolytes with high F and Na contents.

4.
Bioresour Technol ; 410: 131310, 2024 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-39163948

RESUMEN

CaO modified with acetic acid solution or sodium hydroxide (H-CaO/OH-CaO) was used to explore the relationship between the physical and chemical properties of CaO and the components of bio-oil during the pyrolysis of rice straw (RS) and model compounds via experiment and density functional theory(DFT) simulation. The results showed that the modification changed the properties of CaO, and thus the catalytic performance on production of bio-oil components. H-CaO with the larger number of strong basic sites (1.10 âˆ¼ 2 times than commercial CaO) and the longer Ca-O bond length showed the better selectivity and performance on formation of ketones (the maximum relative content in bio-oil reached 43 %). The conversion pathway of cellulose/hemicellulose was changed by H-CaO, which promoted the formation of ketones. The easier combining of H-CaO with the pyrolysis primary products due to the longer Ca-O bond was the key to its better performance.

5.
Water Sci Technol ; 90(4): 1267-1279, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39215737

RESUMEN

The study investigates the effect of the oxidant calcium oxide (CaO) on the codigestion of excess sludge (ES) and plant waste (PW) under mesophilic anaerobic conditions to enhance methane production. The findings indicate that CaO significantly elevated methane yield in the codigestion system, with an optimum CaO addition of 6% resulting in a maximum methane production of 461 mL/g volatile solids, which is approximately 1.3 times that of the control group. Mechanistic exploration revealed that CaO facilitated the disintegration of organic matter, enhanced the release of soluble chemical oxygen demand, and increased the concentrations of soluble proteins and polysaccharides within the codigestion substrate. The presence of CaO was conducive to the generation and biological transformation of volatile fatty acids, with a notable accumulation of acetic acid, a smaller carboxylic acid within the VFAs. The proportion of acetate in the CaO-amended group increased to 32.6-36.9%. Enzymatic analysis disclosed that CaO enhanced the activity of hydrolytic and acidogenic enzymes associated with the ES and PW codigestion process but suppressed the activity of coenzyme F420. Moreover, CaO augmented the nutrient load in the fermentation liquid. The study provides an alternative scheme for the efficient resource utilization of ES and PW.


Asunto(s)
Compuestos de Calcio , Óxidos , Aguas del Alcantarillado , Compuestos de Calcio/química , Anaerobiosis , Óxidos/química , Metano/metabolismo , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Ácidos Grasos Volátiles/metabolismo , Análisis de la Demanda Biológica de Oxígeno
6.
Adv Sci (Weinh) ; : e2406095, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39099408

RESUMEN

Catalytic activation of Caryl-O bonds is considered as a powerful strategy for the production of aromatics from lignin. However, due to the high reduction potentials of diaryl ether 4-O-5 linkage models, their single electron reduction remains a daunting challenge. This study presents the blue light-induced bifunctional N-heterocyclic carbene (NHC)-catalyzed one-electron reduction of diaryl ether 4-O-5 linkage models for the synthesis of trivalent phosphines. The H-bond between the newly devised bifunctional NHC and diaryl ethers is responsible for the success of the single electron transfer. Furthermore, this approach demonstrates selective one-electron reduction of unsymmetric diaryl ethers, oligomeric phenylene oxide, and lignin model.

7.
Environ Res ; 260: 119626, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39019143

RESUMEN

The utilization of bio-oil derived from biomass presents a promising alternative to fossil fuels, though it faces challenges when directly applied in diesel engines. Microemulsification has emerged as a viable strategy to enhance bio-oil properties, facilitating its use in hybrid fuels. This study explores the microemulsification of Jatropha bio-oil with ethanol, aided by a surfactant, to formulate a hybrid liquid fuel. Additionally, a bio-nano CaO heterogeneous catalyst synthesized from eggshells is employed to catalyse the production of Jatropha biodiesel from the microemulsified fuel using microwave irradiation. The catalyst is characterized through UV-Vis, XRD, and SEM analysis. The investigation reveals a significant reduction in CO, CO2, and NOX emissions with the utilization of microemulsion-based biodiesel blends. Various blends of conventional diesel, Jatropha biodiesel, and ethanol are prepared with different ethanol concentrations (5, 10, and 20 wt%). Engine performance parameters, including fuel consumption, NOX emission, and brake specific fuel consumption, are analyzed. Results indicate that the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend exhibits superior performance compared to conventional diesel, Jatropha biodiesel, and other blends. The fuel consumption of the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend is measured at 554.6 g/h, surpassing that of conventional diesel and other biodiesel blends. The presence of water (0.14 %) in the blend reduces the heating value, consequently increasing the energy requirement. CO and CO2 emissions for the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend are notably lower compared to conventional C-18 hydrocarbons and various biodiesel blends. These findings accentuate the efficacy of the microemulsion process in enhancing fuel characteristics and reducing emissions. Further investigations could explore optimizing the emulsifying agents and their impact on engine performance and emission characteristics, contributing to the advancement of sustainable fuel technologies.


Asunto(s)
Biocombustibles , Cáscara de Huevo , Jatropha , Óxidos , Biocombustibles/análisis , Cáscara de Huevo/química , Jatropha/química , Catálisis , Óxidos/química , Animales , Emulsiones , Compuestos de Calcio/química , Etanol/química , Emisiones de Vehículos/análisis
8.
Cureus ; 16(6): e62380, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39006557

RESUMEN

Background In the face of the escalating COVID-19 pandemic amid shortages of medications and vaccines, a Vietnamese herbal formula known as Shen Cao Gan Jiang Tang (SCGJT) has been put into use for non-severe COVID-19 patients. This study aims to assess its efficacy and safety. Methods A multicenter, open-label, randomized controlled trial was conducted on 300 patients with non-severe COVID-19, randomly assigned into two groups: 150 receiving standard care (control group) and 150 receiving additional SCGJT for 10 days (SCGJT group). Time to resolution of symptoms, symptom severity, disease progression, time to discharge, the National Early Warning Score 2 (NEWS2) score, usage of Western drugs, time to viral clearance, and safety outcomes were continuously monitored. Results The SCGJT group exhibited faster symptom resolution (median: 9 vs. 13 days) and improved symptom severity, including cough, fatigue, hypogeusia, muscle aches, nasal congestion, runny nose, and sore throat, compared to the control group. Although there was a lower rate of severe progression in the SCGJT group (0.7% vs. 4.7%), the difference was not statistically significant. The time to discharge was significantly shorter in the SCGJT group (median: 7 vs. 8 days). Changes in the NEWS2 score did not show significant differences between groups. SCGJT has been demonstrated to reduce the need for symptomatic relief medications and hasten SARS-CoV-2 viral clearance. No adverse events were reported, and routine tests showed no significant differences. Conclusions SCGJT is safe and has potential clinical efficacy in non-severe COVID-19 patients. However, data regarding preventing severe progression remains inconclusive. Further studies should be conducted in light of the current state of the COVID-19 pandemic.

9.
Nanomaterials (Basel) ; 14(13)2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38998734

RESUMEN

The reuse of waste materials has recently become appealing due to pollution and cost reduction factors. Using waste materials can reduce environmental pollution and product costs, thus promoting sustainability. Approximately 95% of calcium carbonate-containing waste eggshells end up in landfills, unused. These eggshells, a form of bio-waste, can be repurposed as catalytic electrode material for various applications, including supercapacitors, after being converted into CaO. Similarly, used waste battery electrode materials pose environmental hazards if not properly recycled. Various types of batteries, particularly lithium-ion batteries, are extensively used worldwide. The recycling of used lithium-ion batteries has become less important considering its low economic benefits. This necessitates finding alternative methods to recover and reuse the graphite rods of spent batteries. Therefore, this study reports the conversion of waste eggshell into calcium oxide by high-temperature calcination and extraction of nanographite from spent batteries for application in energy storage fields. Both CaO and CaO/graphite were characterized for their structural, morphological, and chemical compositions using XRD, SEM, TEM, and XPS techniques. The prepared CaO/graphite nanocomposite material was evaluated for its efficiency in electrochemical supercapacitor applications. CaO and its composite with graphite powder obtained from used lithium-ion batteries demonstrated improved performance compared to CaO alone for energy storage applications. Using these waste materials for electrochemical energy storage and conversion devices results in cheaper, greener, and sustainable processes. This approach not only aids in energy storage but also promotes sustainability through waste management by reducing landfills.

10.
Curr Issues Mol Biol ; 46(7): 7187-7218, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39057069

RESUMEN

The oxygen evolution within photosystem II (PSII) is one of the most enigmatic processes occurring in nature. It is suggested that external proteins surrounding the oxygen-evolving complex (OEC) not only stabilize it and provide an appropriate ionic environment but also create water channels, which could be involved in triggering the ingress of water and the removal of O2 and protons outside the system. To investigate the influence of these proteins on the rate of oxygen release and the efficiency of OEC function, we developed a measurement protocol for the direct measurement of the kinetics of oxygen release from PSII using a Joliot-type electrode. PSII-enriched tobacco thylakoids were used in the experiments. The results revealed the existence of slow and fast modes of oxygen evolution. This observation is model-independent and requires no specific assumptions about the initial distribution of the OEC states. The gradual removal of exogenous proteins resulted in a slowdown of the rapid phase (~ms) of O2 release and its gradual disappearance while the slow phase (~tens of ms) accelerated. The role of external proteins in regulating the biphasicity and efficiency of oxygen release is discussed based on observed phenomena and current knowledge.

11.
Heliyon ; 10(13): e33790, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39044969

RESUMEN

Brassica carinata seed is a non-edible oil containing crop grown for oil-based product development like biodiesel synthesis. However, recently technical challenges such as availability of feedstock, type of catalyst, cost, and quality of biodiesel hindered the feasibility and utilization of biodiesel. Thus, this study addressed those problems under the production of fatty acid methyl ester through trans-esterification reaction in the presence of heterogeneous catalyst ( CaO ), and methanol alcohol from Ethiopian brassica carinata seed oil. The synergetic and antagonistic effects of selected parameters (temperature, methanol to oil molar ratio, and amount of catalyst) on the yield of FAME were analyzed. Box-Behnken response surface methodology statistical analysis was applied to examine the parametric interaction effect, and optimization of reaction conditions. Accordingly, 90 % of fatty acid methyl ester (FAME) yield was achieved at the optimum value of 65 °C temperature, 14.85: 1 methanol to oil molar ratio, and 13.77 % catalyst load. The fuel properties of the resulted biodiesel were determined following standard procedures, and the results were within the standard limits (ASTM D6751). This implies that brassica carinata oil over heterogeneous catalyzed reaction medium under optimum reaction conditions provides higher biodiesel yield.

12.
Water Res ; 261: 122013, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38981354

RESUMEN

Ultrafiltration (UF) is increasingly used in the pretreatment of shale gas produced water (SGPW), whereas severe membrane fouling hampers its actual operation. In this work, ferrate(VI)-based oxidation was proposed for membrane fouling alleviation in SGPW pretreatment, and the activation strategies of calcium peroxide (CaO2) and ultraviolet (UV) were selected for comparison. The findings indicated that UV/Fe(VI) was more effective in removing fluorescent components, and the concentration of dissolved organic carbon was reduced by 24.1 %. With pretreatments of CaO2/Fe(VI) and UV/Fe(VI), the terminal specific membrane flux was elevated from 0.196 to 0.385 and 0.512, and the total fouling resistance diminished by 52.7 % and 76.2 %, respectively. Interfacial free energy analysis indicated that the repulsive interactions between pollutants and membrane were notably enhanced by Fe(VI)-based oxidation, thereby delaying the deposition of cake layers on the membrane surface. Quenching and probe experiments revealed that high-valent iron intermediates (Fe(IV)/Fe(V)) played significant roles in both CaO2/Fe(VI) and UV/Fe(VI) processes. Besides, hydroxyl radicals (•OH) were also important reactive species in the UV/Fe(VI) treatment, and the synergistic effect of Fe(IV)/Fe(V) and •OH showed a positive influence on SGPW fouling mitigation. In general, these findings establish a theoretical underpinning for the application of Fe(VI)-based oxidation for UF membrane fouling mitigation in SGPW pretreatment.


Asunto(s)
Radical Hidroxilo , Hierro , Membranas Artificiales , Oxidación-Reducción , Ultrafiltración , Hierro/química , Radical Hidroxilo/química , Purificación del Agua/métodos
13.
Environ Res ; 258: 119449, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38901814

RESUMEN

In the current study, Coccinia grandis fruit extract was used to synthesize calcium oxide nanoparticles (CaO NPs) in an economical and environmentally friendly manner. UV-Vis spectroscopy and Fourier transform infrared spectroscopy revealed that the phytoconstituents found in Coccinia grandis fruit extract facilitated the production of CaO NPs by acting as better stabilizing, biodegradable, and reducing agents. The synthesized CG-CaO NPs were also tested for photocatalytic activity in the breakdown of selective dyes such as methyl red, methyl orange, and methylene blue in the presence of sunlight. The degradation percentage was determined by analyzing the color removal rates for all dye components. After 6 h of reaction, the IC50 values for methyl red, methyl orange, as well as methylene blue dyes were 73, 107, and 133, respectively. The CG-CaO NPs were further evaluated for their antimicrobial activity against specific bacteria and fungi using the agar-well diffusion method. 200 µg/mL CG-CaO NPs inhibited Aspergillus niger, Escherichia coli, Salmonella typhi, Streptococcus mutans, and Staphylococcus aureus at zones of 13, 14, 16, 14, and 15 mM, respectively. Further checkerboard assay confirmed the antagonism effect with gentamicin. Also, Artemia salina toxicity assay showed that the LD50 value of CaO NPs was 400 µg/mL of CaO NPs. The findings confirm that Coccinia grandis-mediated CG-CaO NPs can be used effectively in antimicrobial and environmental settings.


Asunto(s)
Compuestos de Calcio , Colorantes , Cucurbitaceae , Nanopartículas , Óxidos , Extractos Vegetales , Óxidos/química , Compuestos de Calcio/química , Compuestos de Calcio/farmacología , Nanopartículas/química , Cucurbitaceae/química , Colorantes/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Compuestos Azo/química , Animales , Artemia/efectos de los fármacos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Catálisis , Frutas/química , Bacterias/efectos de los fármacos
14.
Int J Biol Macromol ; 273(Pt 1): 132891, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38848852

RESUMEN

Electrospun nanocomposite scaffolds with improved bioactive and biological properties were fabricated from a blend of polycaprolactone (PCL) and starch, and then combined with 5 wt% of calcium oxide (CaO) nanoparticles sourced from eggshells. SEM analyses showed scaffolds with fibrillar morphology and a three-dimensional structure. The hydrophilicity of scaffolds was improved with starch and CaO nanoparticles, which was evidenced by enhanced water absorption (3500 %) for 7 days. In addition, PCL/Starch/CaO scaffolds exhibited major degradation, with a mass loss of approximately 60 % compared to PCL/Starch and PCL/CaO. The PCL/Starch/CaO scaffolds decreased in crystallinity as intermolecular interactions between the nanoparticles retarded the mobility of the polymeric chains, leading to a significant increase in Young's modulus (ca. 60 %) and a decrease in tensile strength and elongation at break, compared to neat PCL. SEM-EDS, FT-IR, and XRD analyses indicated that PCL/Starch/CaO scaffolds presented a higher biomineralization capacity due to the ability to form hydroxyapatite (HA) in their surface after 28 days. The PCL/Starch/CaO scaffolds showed attractive biological performance, allowing cell adhesion and viability of M3T3-E1 preosteoblastic cells. In vivo analysis using a subdermal dorsal model in Wistar rats showed superior biocompatibility and improved resorption process compared to a pure PCL matrix. This biological analysis suggested that the PCL/Starch/CaO electrospun mats are suitable scaffolds for guiding the regeneration of bone tissue.


Asunto(s)
Huesos , Compuestos de Calcio , Nanopartículas , Óxidos , Poliésteres , Almidón , Ingeniería de Tejidos , Andamios del Tejido , Almidón/química , Poliésteres/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Nanopartículas/química , Óxidos/química , Compuestos de Calcio/química , Ratas , Ratones , Materiales Biocompatibles/química , Ratas Wistar , Línea Celular , Nanocompuestos/química
15.
Environ Sci Pollut Res Int ; 31(27): 39823-39838, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38833049

RESUMEN

Sea surface temperature (SST), with its complex and dynamic behavior, is a major driver of ocean-atmosphere interactions. The purpose of this study is to investigate the behavior of SST and its prediction using a chaotic approach. Average mutual information (AMI) and Cao methods were used to reconstruct the phase space. The Lyapunov exponent and correlation dimension were used to investigate chaos. The Lyapunov exponent index was used to predict SST with a 5-year average prediction horizon using the local prediction method between 2023 and 2027. The results showed a 3-month delay time for the Pacific and Antarctic Oceans, and a 2-month delay time for the Atlantic, Indian, and Arctic Oceans. The optimal embedding dimension for all oceans is between 6 and 7. Our analysis reveals that the dynamics of SST in all oceans exhibit varying degrees of chaos, as indicated by the correlation dimension. The local prediction method achieves relatively accurate short-term SST predictions due to the clustering of SST points around specific attractors in the phase space. However, in the long term, the accuracy of this method decreases as the points in the phase space of SST can spread randomly. The model performance ranking with a Percent Mean Relative Absolute Error shows that the Indian Ocean has the best performance compared to other oceans, while the Atlantic, Pacific, and Antarctic and Arctic Oceans are in the next ranks. This study contributes to understanding the dynamics of SST and has practical value for use in the development of climate models.


Asunto(s)
Temperatura , Modelos Teóricos , Océanos y Mares
16.
Plant Biol (Stuttg) ; 26(5): 855-867, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38886872

RESUMEN

In Mediterranean regions, severe summers are becoming more common, leading to restrictions to vine productivity and yield quality, requiring sustainable practices to support this sector. We assessed the behaviour of three red grapevine varieties from the Douro Region to examine their tolerance to summer climate stress from the perspective that the less common varieties may have potential for increased use in a climate change scenario. Leaf and fruit biochemical profile, antioxidant activity and fruit colorimetric parameters were assessed at different phenological stages in Aragonez (AR), Tinto Cão (TC) and Touriga Nacional (TN) grape varieties. All three varieties exhibit significant variability in phenological timing, influenced by genetic and environmental factors. Photosynthetic pigment strategies differed among varieties. Chlorophyll content in AR was high to cope with high radiation, while TN displaying a balanced approach, and TC had lower pigment levels, with higher levels of phenolics, antioxidants, and soluble sugars, particularly during stress. The variations in berry biochemical profile highlight the distinct characteristics of the varieties. TC and TN show potential for coping with climate change, having elevated total acidity, while AR has larger and heavier berries with distinct coloration. These findings reinforce the need to study the behaviour of different varieties in each Terroir, to understand their diverse strategies to deal with summer climate stress. This will help in selecting the most suitable variety for these conditions under vineyard management in the Douro Region.


Asunto(s)
Antioxidantes , Clorofila , Frutas , Vitis , Vitis/crecimiento & desarrollo , Vitis/fisiología , Vitis/metabolismo , Clorofila/metabolismo , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Antioxidantes/metabolismo , Región Mediterránea , Cambio Climático , Estaciones del Año , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Clima , Fotosíntesis/fisiología
17.
RECIIS (Online) ; 18(2)abr.-jun. 2024.
Artículo en Portugués | LILACS, Coleciona SUS | ID: biblio-1561667

RESUMEN

A pandemia gerou impactos sociais e econômicos, como o trabalho informal dos que se ocupam do serviço de café de rua, ampliado na retomada pós-isolamento. O artigo analisa as significações construídas pelas instalações do serviço nas ruas de São Paulo (SP) e Vitória (ES), enquanto manifestações do empreendedo-rismo por necessidade. O corpus foi coletado em dias úteis, no início das manhãs, em diversos pontos das capitais. A semiótica discursiva sustentou a análise, e o seu método permitiu traçar isotopias conectoras de figuras e temas. Os resultados apontam para comunicação dos sentidos da informalidade, casualidade e familiaridade, marcados pela presença feminina, pela autonomia imposta aos sujeitos produtor/vendedor e consumidor e pela conexão entre a energia proporcionada pela bebida e o trabalho. Esses significadosvêm embebidos no risco vivido por esses sujeitos, aconchegados entre si e alijados da proteção de políticas públicas de trabalho, condições sanitárias, serviços de transporte e saúde.


The pandemic has generated social and economic impacts, such as the informal work of those who sell coffee on the streets, expanded in the post-isolation resumption. The article analyzes the meanings constructed by the service facilities in São Paulo (SP) and Vitória (ES), as demonstrations of the entrepreneurship by necessity. The corpus was collected on weekdays, in places of the state capitals. Discursive semiotics underpins the analysis, suggesting connective isotopies of figures and themes. The results point to the communication of the senses of informality, casualness and familiarity, marked by the female presence, by the autonomy imposed on the subjects producer/seller and consumer and by the connection between the energy given by the drink and the work. These meanings are embedded in the risk experienced by these subjects, snuggled among themselves and excluded from the protection of public policies of work, sanitary conditions, transportation and health services.


La pandemia generó impactos sociales y económicos, como el trabajo informal de quienes se ocupan del servicio de café en las calles, ampliado en la reanudación post-aislamiento. El artículo analiza los signifi-cados construidos por las instalaciones de servicios en las calles de São Paulo (SP) y Vitória (ES), como manifestaciones de emprendimiento por necesidad. El corpus fue recolectado entresemana, en puntos de las capitales. La semiótica discursiva sustenta el análisis y permitió trazar isotopías conectoras de figuras y temas. Los resultados apuntan para la comunicación de los significados de informalidad, marcados por la presencia femenina, por la autonomía impuesta a los sujetos productor/vendedor y consumidor, y por la conexión entre la energía dada por la bebida y el trabajo. Estos significados están incrustados en el riesgo vivido por estos sujetos, y excluidos de la protección de las políticas públicas laborales, las condiciones sanitarias, los servicios de transporte y salud.


Asunto(s)
Cambio Social , Factores Socioeconómicos , Emprendimiento , Café , Derecho al Trabajo , Desempleo , Perfiles Sanitarios , COVID-19
18.
Chem Biol Interact ; 398: 111076, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38815669

RESUMEN

Mitophagy is a distinct physiological process that can have beneficial or deleterious effects in particular tissues. Prior research suggests that mitophagic activity can be triggered by CaO2-PM-CsPbBr3 QDs, yet the specific role that mitophagy plays in hepatic injury induced by CaO2-PM-CsPbBr3 QDs has yet to be established. Accordingly, in this study a series of mouse model- and cell-based experiments were performed that revealed the ability of CaO2-PM-CsPbBr3 QDs to activate mitophagic activity. Golm1 was upregulated in response to CaO2-PM-CsPbBr3 QDs treatment, and overexpressing Golm1 induced autophagic flux in the murine liver and hepatocytes, whereas knocking down Golm1 had the opposite effect. CaO2-PM-CsPbBr3 QDs were also able to Golm1 expression, in turn promoting the degradation of P53 and decreasing the half-life of this protein. Overexpressing Golm1 was sufficient to suppress the apoptotic death of hepatocytes in vitro and in vivo, whereas the knockdown of Golm1 had the opposite effect. The ability of Golm1 to promote p53-mediated autophagy was found to be associated with the disruption of Beclin-1 binding to Bcl-2, and the Golm1 N-terminal domain was determined to be required for p53 interactions, inducing autophagic activity in a manner independent of helicase activity or RNA binding. Together, these results indicate that inhibiting Golm1 can promote p53-dependent autophagy via disrupting Beclin-1 binding to Bcl-2, highlighting a novel approach to mitigating liver injury induced by CaO2-PM-CsPbBr3 QDs.


Asunto(s)
Apoptosis , Autofagia , Beclina-1 , Hepatocitos , Proteínas de la Membrana , Mitocondrias , Proteínas Proto-Oncogénicas c-bcl-2 , Puntos Cuánticos , Especies Reactivas de Oxígeno , Proteína p53 Supresora de Tumor , Animales , Hepatocitos/metabolismo , Hepatocitos/citología , Proteína p53 Supresora de Tumor/metabolismo , Beclina-1/metabolismo , Ratones , Especies Reactivas de Oxígeno/metabolismo , Mitocondrias/metabolismo , Puntos Cuánticos/química , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Humanos , Mitofagia , Masculino , Ratones Endogámicos C57BL
19.
J Environ Manage ; 359: 120782, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38669884

RESUMEN

Capturing CO2 using clamshell/eggshell-derived CaO adsorbent can not only reduce carbon emissions but also alleviate the impact of trash on the environment. However, organic acid was usually used, high-temperature calcination was often performed, and CO2 was inevitably released during preparing CaO adsorbents from shell wastes. In this work, CaO-based CO2 adsorbent was greenly prepared by calcium-induced hydrogenation of clamshell and eggshell wastes in one pot at room/moderate temperature. CO2 adsorption experiments were performed in a thermogravimetric analyzer (TGA). The adsorption performance of the adsorbents obtained from the mechanochemical reaction (BM-C/E-CaO) was superior to that of the adsorbents obtained from the thermochemical reaction (Cal-C/E-CaO). The CO2 adsorption capacity of BM-C-CaO at 650 °C is up to 36.82 wt%, but the adsorption decay rate of the sample after 20 carbonation/calcination cycles is only 30.17%. This study offers an alternative energy-saving method for greenly preparing CaO-based adsorbent from shell wastes.


Asunto(s)
Dióxido de Carbono , Tecnología Química Verde , Eliminación de Residuos , Tecnología Química Verde/métodos , Dióxido de Carbono/análisis , Dióxido de Carbono/química , Hidrogenación , Temperatura , Exoesqueleto/química , Cáscara de Huevo/química , Eliminación de Residuos/métodos , Adsorción
20.
Environ Technol ; : 1-11, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619987

RESUMEN

Coupling chemical oxidation and biodegradation to remediate polycyclic aromatic hydrocarbon (PAH)-contaminated sediment has recently gained significant attention. In this study, calcium peroxide nanoparticles (nCaO2) were utilized as an innovative oxygen-releasing compound for in-situ chemical oxidation. The study investigates the bioremediation of phenanthrene (PHE)-contaminated sediment inoculated with Sphingomonas sp. DSM 7526 bacteria and treated with either aeration or nCaO2. Using three different culture media, the biodegradation efficiencies of PHE-contaminated anoxic sediment, aerobic sediment, and sediment treated with 0.2% w/w nCaO2 ranged from 57.45% to 63.52%, 69.87% to 71.00%, and 92.80% to 94.67%, respectively. These values were significantly higher compared to those observed in non-inoculated sediments. Additionally, the type of culture medium had a prominent effect on the amount of PHE removal. The presence of minerals in the culture medium increased the percentage of PHE removal compared to distilled water by about 2-10%. On the other hand, although the application of CaO2 nanoparticles negatively impacted the abundance of sediment bacteria, resulting in a 30-42% decrease in colony-forming units after 30 days of treatment, the highest PHE removal was obtained when coupling biodegradation and chemical oxidation. These findings demonstrate the successful application of bioaugmentation and chemical oxidation processes for treating PAH-contaminated sediment.

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