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1.
Torture ; 34(1): 89-99, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38975918

RESUMEN

INTRODUCTION: Rubber bullets are projectiles whose use is potentially lethal. Between 1976 and 2017, they have caused at least 23 deaths and dozens of injuries in Spain, many of them serious, with loss of sight being the main type. In the period 2000 - 2020 alone, more than 40 people have been affected. METHODS: We review the legal framework, human impacts that go far beyond statistics and medical and psychosocial approaches. RESULTS: The paper focuses on key learnings in survivors' organisation, the process towards the prohibition of these weapons and strategic litigation, forensic documenta-tion and political advocacy.


Asunto(s)
Goma , Tortura , Humanos , España , Heridas por Arma de Fuego
2.
Torture ; 34(1): 62-70, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38975915

RESUMEN

INTRODUCTION: The article examines the experiences of protesters and bystanders who have sustained eye injuries from rubber bullets fired by the police. Use of rubber bullets by police officers during public protests is officially regulated, but there is insufficient documentation about the nature of fatal and non-fatal injuries linked to rubber bullet use during protests in South Africa. METHODS: We pres-ent three case studies based on data gathered from student protests, community protests, and media reports. Through the analysis of these sources, the article presents the personal stories of individuals who have experienced eye injuries, detailing how the incidents occurred and the subsequent impact on their lives. It also examines the accessibility of medical, psychological, and legal services available to victims in addressing the consequences of these injuries. RESULTS: The cases studies illustrate that rubber bullets were used frequently and often without due caution by police officers during the events examined. The use of rubber bullets was linked to numerous eye injuries, resulting in lasting psycho-logical and physical consequences for those affected. DISCUSSION: Rubber bullet-related eye injuries during protests are disturbingly common in South Africa. Consequently, there is an urgent need to provide essential services and support to those who suffer from these life-altering incidents.


Asunto(s)
Lesiones Oculares , Goma , Humanos , Sudáfrica , Masculino , Adulto , Heridas por Arma de Fuego , Policia , Femenino
3.
Torture ; 34(1): 128-134, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38975921

RESUMEN

My name is Carles Guillot and I am 52 years old. On 17 July 2001, 23 years ago now, during a protest against the illegal as-sault and eviction of a squatted house, the Kasa de la Muntan-ya, a national police officer shot me point-blank in the face and permanently damaged my right eyeball. As the neighbourhood was taken over by the police, we had to wait a few hours before we could go to a hospital. Finally, some colleagues took me to the Bellvitge Hospital, the furthest hospital in the area, to avoid being identified by the police. The prognosis was clear: I would be one-eyed for life.The first days and weeks were very hard. Pain, headaches, and anger, a lot of anger.


Asunto(s)
Sobrevivientes , Humanos , Sobrevivientes/psicología , Persona de Mediana Edad , Masculino , Heridas por Arma de Fuego , Goma , Tortura/psicología , Lesiones Oculares
4.
Appl Ergon ; 120: 104341, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38986304

RESUMEN

First responder professionals are at high risk for work-related injuries (e.g., extreme temperatures, chemical and biological threats); boots are essential to ensure body protection since they have full contact with the ground in all scenarios. A substantial body of work has investigated the necessity of improvements in protective boots, but there is limited research conducted on boots with fit-adjustable fasteners for secure and adjustable fit within this context. Thus, this study explored the areas for improvement in boot design for the development of form-fitting and yet comfortable boots focusing on two different boot designs, prototype all-hazards tactical boots (lace-up) and rubber boots (slip-on). Findings indicated that the boot design should address participants' concerns with the material choices of boots, specifically with bulkiness, weight, and flexibility. Our findings provide insights into boot material and design choices to improve protective boots for first responders.


Asunto(s)
Diseño de Equipo , Sustancias Peligrosas , Zapatos , Humanos , Masculino , Adulto , Femenino , Socorristas , Traumatismos Ocupacionales/prevención & control , Ropa de Protección , Goma , Persona de Mediana Edad
5.
Artículo en Inglés | MEDLINE | ID: mdl-38851151

RESUMEN

In this study, a magnetic three-dimensional nano-composite based on Rubber-Fe3O4@Ni-Co Layered double hydroxide derived from ZIF-67 template was synthesized by a hydrothermal method. The proposed nano-composite was used as a sorbent for the enrichment of trace amounts of anti-cancer drugs (dasatinib and erlotinib hydrochloride) from plasma samples followed by determination using high-performance liquid chromatographic analysis (HPLC-UV). The synthesized nano-sorbent was characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, vibrating-sample magnetometer, Brunauer-Emmett-Teller surface analysis, Barrett-Joyner-Halenda pore size analysis and energy dispersive X-ray spectroscopy. Under optimal experimental conditions, factors affecting on extraction efficiency such as pH, ionic strength, extraction temperature and time, desorption solvent and time, the limit of detection (LODs) and the limit of quantification (LOQs) were obtained as 0.6, 2 µg/L for both of dasatinib and erlotinib, respectively. Also, linear range of the method were 2-500 and 2-1000 µg/L for dasatinib and erlotinib, respectively. Relative standard deviations (RSD%) for the repeatability of extraction on sorbent to sorbent were obtained as 3.59, 1.97 %, and one sorbent reusability were investigated and relative standard deviation values were obtained 5.35, 3.30 % for dasatinib and erlotinib, respectively.


Asunto(s)
Antineoplásicos , Clorhidrato de Erlotinib , Límite de Detección , Goma , Goma/química , Antineoplásicos/sangre , Antineoplásicos/química , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Humanos , Clorhidrato de Erlotinib/sangre , Clorhidrato de Erlotinib/química , Modelos Lineales , Dasatinib/sangre , Dasatinib/química , Hidróxidos/química , Imidazoles/química , Imidazoles/sangre , Adsorción , Extracción en Fase Sólida/métodos , Cobalto/química , Cobalto/sangre , Nanoestructuras/química , Zeolitas
6.
Int J Biol Macromol ; 273(Pt 1): 133056, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38862058

RESUMEN

Solar steam generation (SSG) offers a sustainable approach to fresh water production. Herein, a novel dual-functional natural rubber/carbon black composite foam evaporator is presented for a cost-efficient SSG system that both produces fresh water and eliminates heavy metals present in the water. The composite foam is produced using the Dunlop process, and in its optimized form, it absorbed >96 % of sunlight. The foam evaporator exhibited a thermal conductivity of 0.052 W/m⋅K, a water evaporation rate of 1.40 kg/m2/h, converted 83.38 % of light to heat under 1 sun irradiation, and showed outstanding stability. The technology required to produce this composite foam is already available to make large-scale production feasible, while the natural raw materials are abundant. On the basis of its performance qualities, the rubber foam composite appears to be an excellent candidate for application as a viable solar absorber for SSG to produce fresh, clean water for commercial purposes.


Asunto(s)
Metales Pesados , Goma , Luz Solar , Goma/química , Metales Pesados/química , Látex/química , Purificación del Agua/métodos , Agua/química , Descontaminación/métodos , Vapor , Contaminantes Químicos del Agua/química , Hollín/química
7.
Environ Sci Pollut Res Int ; 31(29): 41964-41979, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38856856

RESUMEN

Potential toxicity of treated effluents of selected natural rubber processing industries was evaluated by integrating physicochemical analysis with Daphnia magna and Poecilia reticulata bioassays as ecotoxicity tools. Further, the efficacy of the constructed wetland treatments practiced by the industries for reducing the ecotoxicity of the final effluents reaching the receiving water course was assessed. Even after passing through the constructed wetlands, some of the measured physicochemical parameters of the final effluents did not comply with the stipulated rubber processing effluent regulatory limits. Acute toxicity data of treated effluents demonstrated greater susceptibility of D. magna compared to P. reticulata. Erythrocytic abnormality tests with P. reticulata revealed that rubber industry effluents contained cytogenotoxic contaminations which had not been completely eliminated by the treatment processes. Wetland treatment technique was not effective in reducing the cytogenotoxic effects of final effluents reaching the receiving water course. The use of ecotoxicity tools for optimization of rubber industry effluent treatment processes would help to reduce potential toxic/cytogenotoxic effects of effluent receiving waterbodies considering sustainable development goals focusing on ecosystem safety.


Asunto(s)
Daphnia , Goma , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/toxicidad , Daphnia/efectos de los fármacos , Humedales , Residuos Industriales , Eliminación de Residuos Líquidos , Poecilia , Ecotoxicología
8.
An Acad Bras Cienc ; 96(3): e20230387, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38865508

RESUMEN

The blend of butadiene and acrylonitrile copolymer (NBR) with natural poly-cis-isoprene (NR) shows increased resistance to swelling in solvents in comparison to the individual components. In aerospace, NBR rubber is used as thermal protection for rockets and shall not contain other polymers, even in low contents, otherwise, it can affect the protection performance and rocket safety by causing detachment of the elastomer/propellant interface; therefore, this investigation presents methodologies to determine the NR/NBR contents. This study explores different analytical techniques, such as Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy, in the mid-infrared (MIR) by reflection and in the near-infrared by reflectance (NIRA) modes, Furthermore, quantification strategies by univariate, bivariate and multivariate (chemometric) models are evaluated and compared. A proposed methodology, based on multivariate Raman microscopy with partial least squares regression (PLS), showed high linearity (R2 > 0.99) and low error (< 0.82 %). The validation of FT-MIR data for the CH3, which presented lower error (1.3%) than vinylidene band (6%), showed that both methodologies (reflection and NIRA reflectance) can be used for the quantification of NR in NR/NBR. These results constitute a contribution to the state of the art in researching industrial and aerospace elastomeric applications.


Asunto(s)
Goma , Espectrometría Raman , Espectrometría Raman/métodos , Goma/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Butadienos/química , Butadienos/análisis
9.
Int J Biol Macromol ; 272(Pt 1): 132707, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38825274

RESUMEN

Eucommia ulmoides is a temperate gum source plant that produces trans-polyisoprene (TPI), also known as Eucommia rubber. The structural configuration and function of TPI offer a new material with important potential for industrial development. In this study, we detected the TPI content in the leaves of diploid and triploid E. ulmoides plants. The average TPI content in the leaves of triploid E. ulmoides was significantly higher than that of diploid. Transcriptome data and weighted gene co-expression network analyses identified a significant positive correlation between the EuFPS1 gene and TPI content. Overexpression of EuFPS1 increased the density of rubber particles and TPI content, indicating its crucial role in TPI biosynthesis. In addition, the expression of EuHDZ25 in E. ulmoides was significantly positively correlated with EuFPS1 expression. Yeast one-hybrid and dual-luciferase assays demonstrated that EuHDZ25 mainly promotes TPI biosynthesis through positive regulation of EuFPS1 expression. The significantly up-regulated expression of EuHDZ25 and its consequent upregulation of EuFPS1 during the biosynthesis of TPI may partially explain the increased TPI content of triploids. This study provides an important theoretical foundation for further exploring the molecular mechanism of secondary metabolites content variation in polyploids and can help to promote the development and utilization of rubber resources.


Asunto(s)
Eucommiaceae , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta , Proteínas de Plantas , Goma , Eucommiaceae/genética , Eucommiaceae/metabolismo , Eucommiaceae/química , Goma/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Hemiterpenos/biosíntesis , Hemiterpenos/metabolismo
10.
PLoS One ; 19(6): e0304052, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38913628

RESUMEN

A diaphragm pump is a type of volumetric pump that has excellent sealing performance. An electromagnetic diaphragm pump is a kind of widely adopted diaphragm pump that has a simple structure, low power loss, and high cost performance. However, the calculation method of deformation for the electromagnetic diaphragm pump rubber diaphragm is presently lacking. Herein, a calculating method of deformation for the electromagnetic diaphragm pump rubber diaphragm is proposed. By establishing and analyzing a deformation model of the electromagnetic diaphragm pump rubber diaphragm, a theoretical relationship between the deformation of the electromagnetic diaphragm pump rubber diaphragm, the size of the electromagnetic diaphragm pump rubber diaphragm and the pressure of fluid is determined. The experimental results indicate that the biggest difference between the tested axial deformation and the calculated axial deformation of the electromagnetic diaphragm pump rubber diaphragm is 0.04 mm and the calculation results show agreement with the experimental results.


Asunto(s)
Fenómenos Electromagnéticos , Goma , Goma/química , Diseño de Equipo , Modelos Teóricos
11.
Environ Sci Technol ; 58(29): 13056-13064, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38900493

RESUMEN

Rubber-derived chemicals (RDCs) originating from tire and road wear particles are transported into road stormwater runoff, potentially threatening organisms in receiving watersheds. However, there is a lack of knowledge on time variation of novel RDCs in runoff, limiting initial rainwater treatment and subsequent rainwater resource utilization. In this study, we investigated the levels and time-concentration profiles of 35 target RDCs in road stormwater runoff from eight functional areas in the Greater Bay Area, South China. The results showed that the total concentrations of RDCs were the highest on the expressway compared with other seven functional areas. N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), 6PPD-quinone, benzothiazole, and 1,3-diphenylguanidine were the top four highlighted RDCs (ND-228840 ng/L). Seasonal and spatial differences revealed higher RDC concentrations in the dry season as well as in less-developed regions. A lag effect of reaching RDC peak concentrations in road stormwater runoff was revealed, with a lag time of 10-90 min on expressways. Small-intensity rainfall triggers greater contamination of rubber-derived chemicals in road stormwater runoff. Environmental risk assessment indicated that 35% of the RDCs posed a high risk, especially PPD-quinones (risk quotient up to 2663). Our findings contribute to a better understanding of managing road stormwater runoff for RDC pollution.


Asunto(s)
Lluvia , Goma , Ciudades , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , China
12.
Int J Biol Macromol ; 273(Pt 2): 133237, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38897513

RESUMEN

This study investigates the incorporation of block natural rubber (NR) as a viscosity-inducing agent in NR oily liquids designed for drug delivery systems. A variety of liquids, encompassing natural oils, synthetic and non-oil liquids, and a eutectic mixture, were incorporated with NR using solvent displacement technique. Successful formulations were achieved for several oily liquids, with viscosity correlating to NR concentration. Particularly, a eutectic mixture of menthol and camphor exhibited optimal viscosity by direct dissolving enabling the development of transdermal ibuprofen delivery and injectable azithromycin for periodontitis treatment. NR prolonged the release of both drugs. The extended-release ibuprofen system holds promise for transdermal applications, while the azithromycin system displayed inhibitory effects against Staphylococcus aureus, Streptococcus mutans, and Porphyromonas gingivalis, suggesting potential for periodontitis treatment. Overall, this investigation advances the development of NR oily liquids as a versatile drug delivery system that can be applied both on the skin and for the local injection into the periodontal pocket, showcasing promise for various therapeutic applications.


Asunto(s)
Administración Cutánea , Sistemas de Liberación de Medicamentos , Goma , Goma/química , Viscosidad , Bolsa Periodontal/tratamiento farmacológico , Bolsa Periodontal/microbiología , Liberación de Fármacos , Ibuprofeno/administración & dosificación , Ibuprofeno/química , Ibuprofeno/farmacología , Azitromicina/administración & dosificación , Humanos , Animales , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Antibacterianos/química , Periodontitis/tratamiento farmacológico , Periodontitis/microbiología
13.
Environ Res ; 256: 119217, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38788788

RESUMEN

Nowadays, for soil stabilisation and cleaner production of geo-composites, the possibility of utilizing waste rubber is in vogue. The present paper deals with experimentally investigating the mechanical and micro-structural characteristics of weak Indian clayey soil partially substituted with lime (0-3.5%) and waste rubber tyre powder (0-15%). It was observed that, with increasing lime and rubber powder content, the plasticity index of the soil decreases. The shear strength and compaction testing results reveal that adding lime and rubber tyre powder (RTP) enhances the geotechnical performance of clayey soil up to an optimum dosage value. Also, the tri-axial shear testing was performed to obtain stress-strain curves for all considered soil mixes. For modified clayey soil containing 3% lime and 12.5% rubber powder, the cohesion values and bearing capacities improved phenomenally by 36.1% and 88.6% respectively, when compared to clayey soil. Further for this mix, SEM analysis reveals a compacted microstructure which improves dry-density and California's bearing ratio among all modified mixes. The novel co-relations upon regression analysis are found able to predict plasticity index, dry density, bearing capacity and shear strength with higher confidence levels. Overall, the cost-benefit analysis worked out to obtain the optimum cost of construction of footings and flexible pavement shows cost deductions up to 19% and 39% respectively while utilizing modified clay soil mixes containing 3% lime and 12.5% rubber powder in subgrade, ultimately making production stronger, cheaper and environment friendly.


Asunto(s)
Compuestos de Calcio , Arcilla , Óxidos , Goma , Suelo , Compuestos de Calcio/química , Óxidos/química , Goma/química , Suelo/química , Arcilla/química , Silicatos de Aluminio/química
14.
Chemosphere ; 360: 142319, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38735497

RESUMEN

Recent toxicity studies of stormwater runoff implicated N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-quinone) as the contaminant responsible for the mass mortality of coho salmon (Oncorhynchus kisutch). In the wake of this discovery, 6PPD-quinone has been measured in waterways around urban centers, along with other tire wear leachates like hexamethoxymethylmelamine (HMMM). The limited data available for 6PPD-quinone have shown toxicity can vary depending on the species. In this study we compared the acute toxicity of 6PPD-quinone and HMMM to Brook trout (Salvelinus fontinalis) fry and fingerlings. Our results show that fry are ∼3 times more sensitive to 6PPD-quinone than fingerlings. Exposure to HMMM ≤6.6 mg/L had no impact on fry survival. These results highlight the importance of conducting toxicity tests on multiple life stages of fish species, and that relying on fingerling life stages for species-based risk assessment may underestimate the impacts of exposure. 6PPD-quinone also had many sublethal effects on Brook trout fingerlings, such as increased interlamellar cell mass (ILCM) size, hematocrit, blood glucose, total CO2, and decreased blood sodium and chloride concentrations. Linear relationships between ILCM size and select blood parameters support the conclusion that 6PPD-quinone toxicity is an outcome of osmorespiratory challenges imposed by gill impairment.


Asunto(s)
Goma , Trucha , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/toxicidad , Goma/toxicidad , Fenilendiaminas/toxicidad
15.
Int J Biol Macromol ; 270(Pt 1): 132405, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38754661

RESUMEN

Eucommia ulmoides rubber (EUR) is a high-quality natural rubber resource, which can be extracted from different organs of the Eucommia ulmoides tree. In this study, EUR was isolated from the leaves, barks, and pericarps, and the structural characteristics and physicochemical properties of EUR were systematically determined. The accumulation and distribution of EUR in different tissues were assessed through in situ observations combined with cellular and subcellular scales. The preliminary analyses indicated that the variations in the physicochemical properties of EUR across different tissues were associated with its accumulation microstructure. Further analyses by SEM and TEM showed that the initial cell differentiation and fusion resulted in the formation of tubular structures without any nucleus. A limited number of rubber particles were generated within the cytoplasm, concurrent with aggregation and fusion. Eventually, rubber particles filled the entire cytoplasm, and organelles disappeared to form highly aggregated filamentous structures. In addition, the number and area of EUR-containing cells were closely related to the organization sizes of barks and leaves. This study provided valuable insights into Eucommia ulmoides histology and the rubber industry.


Asunto(s)
Eucommiaceae , Hemiterpenos , Goma , Eucommiaceae/química , Hemiterpenos/química , Goma/química , Goma/metabolismo , Hojas de la Planta/química , Corteza de la Planta/química , Butadienos/metabolismo , Butadienos/química
16.
Int J Biol Macromol ; 272(Pt 2): 132602, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38788868

RESUMEN

Tung oil is commonly utilized for coating protection in wooden products, often attracting attention for its appearance, antimicrobial capabilities, and insect-resistant coatings. However, its poor mechanical properties and poor weather resistance stem from excessive self-crosslinking of surplus conjugated double bonds and molecular chains, resulting in poor film wrinkling. Therefore, this study introduces natural rubber via the Diels-Alder reaction to consume the residual double bonds in tung oil, resulting in tung oil/natural rubber composite coatings (NRTO) with excellent mechanical properties and weather resistance. The results indicate that NRTO exhibits excellent mechanical properties, including high elongation (32 %) and strong adhesion (4.55 MPa). Furthermore, NRTO demonstrates outstanding acid resistance and UV aging resistance. Given its many benefits, NRTO film emerges as a promising candidate for substantially protecting wood surfaces in demanding environments.


Asunto(s)
Aceites de Plantas , Goma , Madera , Goma/química , Madera/química , Aceites de Plantas/química , Reacción de Cicloadición , Fenómenos Mecánicos
17.
Am J Dent ; 37(2): 66-70, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38704848

RESUMEN

PURPOSE: To evaluate the effect of different finishing and polishing systems on the surface roughness of a resin composite subjected to simulated saliva-, acid-, and enzyme-induced degradation. METHODS: 160 specimens (n= 40) were fabricated with Filtek Z350 XT nanofilled composite and analyzed for average surface roughness (Ra). The specimens were finished and polished using: AD - Al2O3-impreginated rubberized discs (medium, fine, and superfine grit, Sof-Lex); SD - silicon carbide and Al2O3-impregnated rubberized discs (coarse, medium and fine grit, Jiffy,); MB - 12- and 30-multiblade burs. The control group (CT) (n= 40) comprised specimens with a Mylar-strip-created surface. Specimens from each group were immersed in 1 mL of one of the degradation methods (n= 10): artificial saliva (ArS: pH 6.75), cariogenic challenge (CaC: pH 4.3), erosive challenge (ErC: 0.05M citric acid, pH 2.3) or enzymatic challenge (EzC: artificial saliva with 700 µg/mL of albumin, pH 6.75). The immersion period simulated a time frame of 180 days. Ra measurements were also performed at the post-polishing and post-degradation time points. The data were evaluated by three-way ANOVA for repeated measures and the Tukey tests. RESULTS: There was significant interaction between the finishing/polishing system and the degradation method (P= 0.001). AD presented the greatest smoothness, followed by SD. After degradation, CT, AD and SD groups became significantly rougher, but not the MB group, which presented no difference in roughness before or after degradation. CT and AD groups showed greater roughness in CaC, ErC and EzC than in ArS. The SD group showed no difference in roughness when the specimens were polished with CaC, EzC or ArS, but those treated with ErC had greater roughness. In the MB group, the lower roughness values were found after using CaC and EzC, while the higher values were found using ErC or ArS. CLINICAL SIGNIFICANCE: As far as degradation resistance of nanofilled composite to hydrolysis, bacterial and dietary acids and enzymatic reactions is concerned, restorations that had been finished and polished with Al2O3-impregnated discs had the smoothest surfaces.


Asunto(s)
Óxido de Aluminio , Resinas Compuestas , Pulido Dental , Saliva Artificial , Compuestos de Silicona , Propiedades de Superficie , Resinas Compuestas/química , Pulido Dental/métodos , Humanos , Saliva Artificial/química , Concentración de Iones de Hidrógeno , Óxido de Aluminio/química , Compuestos de Silicona/química , Compuestos Inorgánicos de Carbono/química , Ensayo de Materiales , Nanocompuestos/química , Ácido Cítrico/química , Saliva/enzimología , Saliva/metabolismo , Saliva/química , Erosión de los Dientes , Goma/química , Materiales Dentales/química
18.
J Hazard Mater ; 472: 134461, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38696959

RESUMEN

Previous studies have indicated that tire wear particles (TWPs) leachate exposure induced serious eye injury in fish through inhibiting the thyroid peroxidase (TPO) enzyme activity. However, the main TPO inhibitors in the leachate were still unknown. In this study, we identified 2-Mercaptobenzothiazole (MBT) as the potential TPO inhibitor in the TWPs leachate through references search, model prediction based on Danish QSAR and ToxCast database, molecular docking, and in vivo assay. We further explored the toxic mechanism of MBT under environmentally relevant concentrations. The decreased eye size of zebrafish larvae was mainly caused by the decreased lens diameter and cell density in the inner nuclear layer (INL) and outer nuclear layer (ONL) of the retina. Transcriptomics analysis demonstrated that the eye phototransduction function was significantly suppressed by inhibiting the photoreceptor cell proliferation process after MBT exposure. The altered opsin gene expression and decreased opsin protein levels were induced by weakening thyroid hormone signaling after MBT treatment. These results were comparable to those obtained from a known TPO inhibitor, methimazole. This study has identified MBT as the primary TPO inhibitor responsible for inducing eye impairment in zebrafish larvae exposed to TWPs leachate. It is crucial for reducing the toxicity of TWPs leachate in fish.


Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Animales , Contaminantes Químicos del Agua/toxicidad , Goma , Lesiones Oculares/inducido químicamente , Lesiones Oculares/patología , Benzotiazoles , Yoduro Peroxidasa/metabolismo , Yoduro Peroxidasa/genética , Simulación del Acoplamiento Molecular , Retina/efectos de los fármacos , Larva/efectos de los fármacos
19.
Int J Biol Macromol ; 268(Pt 2): 131946, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692545

RESUMEN

The development of flexible wearable multifunctional electronics has gained great attention in the field of human motion monitoring. However, developing mechanically tough, highly stretchable, and recyclable composite conductive materials for application in multifunctional sensors remained great challenges. In this work, a mechanically tough, highly stretchable, and recyclable composite conductive elastomer with the dynamic physical-chemical dual-crosslinking network was fabricated by the combination of multiple hydrogen bonds and dynamic ester bonds. To prepare the proposed composite elastomers, the polyaniline-modified carboxylate cellulose nanocrystals (C-CNC@PANI) were used as both conductive filler to yield high conductivity of 15.08 mS/m, and mechanical reinforcement to construct the dynamic dual-crosslinking network with epoxidized natural rubber latex to realize the high mechanical strength (8.65 MPa) and toughness (29.57 MJ/m3). Meanwhile, the construction of dynamic dual-crosslinking network endowed the elastomer with satisfactory recyclability. Based on these features, the composite conductive elastomers were used as strain sensors, and electrode material for assembling flexible and recyclable self-powered sensors for monitoring human motions. Importantly, the composite conductive elastomers maintained reliable sensing and energy harvesting performance even after multiple recycling process. This study provides a new strategy for the preparation of recyclable, mechanically tough composite conductive materials for wearable sensors.


Asunto(s)
Celulosa , Elastómeros , Conductividad Eléctrica , Goma , Dispositivos Electrónicos Vestibles , Elastómeros/química , Celulosa/química , Goma/química , Humanos , Nanocompuestos/química , Nanopartículas/química , Fenómenos Mecánicos , Compuestos de Anilina/química
20.
Sci Total Environ ; 934: 173188, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38740197

RESUMEN

Plastic polymers are present in most aspects of routine daily life. Their increasing leakage into the environment poses a threat to environmental, animal, and human health. These polymers are often resistant to microbial degradation and are predicted to remain in the environment for tens to hundreds of years. Fungi have been shown to degrade complex polymers and are considered good candidates for bioremediation (biological pollutant reduction) of plastics. Therefore, we screened 18 selected fungal strains for their ability to degrade polyurethane (PU), polyethylene (PE), and tire rubber. As a proxy for plastic polymer mineralization, we quantified O2 consumption and CO2 production in an enclosed biodegradation system providing plastic as the sole carbon source. In contrast to most studies we demonstrated that the tested fungi attach to, and colonize the different plastic polymers without any pretreatment of the plastics and in the absence of sugars, which were suggested essential for priming the degradation process. Functional polymer groups identified by Fourier-transform infrared spectroscopy (FTIR), and changes in fungal morphology as seen in light and scanning electron microscopy (SEM) were used as indicators of fungal adaptation to growth on PU as a substrate. Thereby, SEM analysis revealed new morphological structures and deformation of the cell wall of several fungal strains when colonizing PU and utilizing this plastic polymer for cell growth. Strains of Fusarium, Penicillium, Botryotinia cinerea EN41, and Trichoderma demonstrated a high potential to degrade PU, rubber, and PE. Growing on PU, over 90 % of the O2 was consumed in <14 days with 300-500 ppm of CO2 generated in parallel. Our study highlights a high bioremediation potential of some fungal strains to efficiently degrade plastic polymers, largely dependent on plastic type.


Asunto(s)
Biodegradación Ambiental , Hongos , Plásticos , Goma , Plásticos/metabolismo , Hongos/metabolismo , Goma/metabolismo , Poliuretanos
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