Functional UV Blocking and Superhydrophobic Coatings Based on Functionalized CeO2 and Al2O3 Nanoparticles in a Polyurethane Nanocomposite.

Water repellency has significant potential in applications like self-cleaning coatings, anti-staining textiles, and electronics. This study introduces a novel nanocomposite system incorporating functionalized Al2O3 and CeO2 nanoparticles within a polyurethane matrix to achieve hydrophobic and UV-blocking properties. The nanoparticles were functionalized using an octadecyl phosphonic acid solution and characterized by FTIR and XPS, confirming non-covalent functionalization. Spin-coated polyurethane coatings with functionalized and non-functionalized Al2O3, CeO2, and binary Al2O3-CeO2 nanoparticles were analyzed. The three-layered Al2O3-CeO2-ODPA binary system achieved a contact angle of 166.4° and 85% transmittance in the visible range. Incorporating this binary functionalized system into a 0.4% w/v polyurethane solution resulted in a nanocomposite with 75% visible transmittance, 60% at 365 nm UV, and a 147.7° contact angle after three layers. These findings suggest that ODPA-functionalized nanoparticles, when combined with a polymer matrix, offer a promising approach to developing advanced hydrophobic and UV-protective coatings with potential applications across various industrial sectors.

Does the Uterine Ozone Therapy Alter the Transcript Profile of Anti- and Proinflammatory Genes in Mares With Endometritis?

This study aimed to evaluate the localised effects of intrauterine ozone therapy on endometrial recovery in mares with endometritis. Our investigation assessed changes in gene expression profiles of anti-inflammatory (IL-1RA and IL-10), proinflammatory (IL-R1B3i and TNFα) and pleiotropic (IL-6) cytokines, along with detailed histological measurements of epithelial and endometrial thickness and the glandular area ratio. Twenty mares were assigned to a 2 × 2 factorial design based on endometritis diagnosis and treatment (control or 42 µg/mL ozone insufflation), resulting in four groups: NC (negative for endometritis/control), NO (negative/ozone), PC (positive/control) and PO (positive/ozone). Oestrus was induced with 2 mg of oestradiol benzoate on Days -1, 1 and 3, plus 1 mg on Day 5. Day 0 marked the initial uterine treatment, followed by insufflations on Days 1 and 2 with O3 (ozone) or O2 (control). Uterine biopsies were taken before treatment on Day 0 and Day 6 for histological analysis and gene expression assessment. Data were analysed using a statistical model that included endometritis status, treatment type, biopsy times (D0 and D6) and their interactions, analysed with Proc Glimmix. Regardless of treatment or endometritis status, significant biopsy effects (p < 0.01) indicated increased epithelial height and endometrial thickness in Day 6 samples. Analysis of IL-1 and TNFα revealed a significant interaction (p < 0.05) among endometritis, treatment and biopsy, with higher IL-1B3i expression on Day 6 in the PC group. The treatment effect (p < 0.04) showed a higher frequency (p < 0.01) of animals with positive modulation in the PC group (66.7%) versus the PO group (0.0%). An interaction effect (p = 0.08) between endometritis and treatment resulted from higher IL-1RA expression on Day 6 in the PC group compared to the PO group. Biopsy effect was significant for IL-10 (p < 0.01), indicating higher values in the second sample associated with tissue repair. In the short-term evaluation, ozone therapy did not influence endometrial morphology and may modulate cytokine expression, specifically the reduction in IL-1 and TNFα levels. Therefore, this therapy appears to be a safe and potentially effective treatment for modulating the inflammatory response in mares with endometritis.

Novel Sol-Gel Synthesis Route for Ce- and V-Doped Ba0.85Ca0.15Ti0.9Zr0.1O3 Piezoceramics.

To meet the current demand for lead-free piezoelectric ceramics, a novel sol-gel synthesis route is presented for the preparation of Ba0.85Ca0.15Ti0.9Zr0.1O3 doped with cerium (Ce = 0, 0.01, and 0.02 mol%) and vanadium (V = 0, 0.3, and 0.4 mol%). X-ray diffraction patterns reveal the formation of a perovskite phase (space group P4mm) for all samples after calcination at 800 °C and sintering at 1250, 1350, and 1450 °C, where it is proposed that both dopants occupy the B site. Sintering studies show that V doping allows the sintering temperature to be reduced to at least 1250 °C. Undoped BCZT samples sintered at the same temperature show reduced functional properties compared to V-doped samples, i.e., d33 values increase by an order of magnitude with doping. The dissipation factor tan δ decreases with increasing sintering temperature for all doping concentrations, while the Curie temperature TC increases for all V-doped samples, reaching 120 °C for high-concentration co-doped samples. All results indicate that vanadium doping can facilitate the processing of BCZT at lower sintering temperatures without compromising performance while promoting thermal property stability.

Changes in SOD and NF-κB Levels in Substantia Nigra and the Intestine through Oxidative Stress Effects in a Wistar Rat Model of Ozone Pollution.

This work aimed to elucidate how O3 pollution causes a loss of regulation in the immune response in both the brain and the intestine. In this work, we studied the effect of exposing rats to low doses of O3 based on the association between the antioxidant response of superoxide dismutase (SOD) levels and the nuclear factor kappa light chains of activated B cells (NFκB) as markers of inflammation. Method: Seventy-two Wistar rats were used, divided into six groups that received the following treatments: Control and 7, 15, 30, 60, and 90 days of O3. After treatment, tissues were extracted and processed using Western blotting, biochemical, and immunohistochemical techniques. The results indicated an increase in 4-hydroxynonenal (4HNE) and Cu/Zn-SOD and a decrease in Mn-SOD, and SOD activity in the substantia nigra, jejunum, and colon decreased. Furthermore, the translocation of NFκB to the nucleus increased in the different organs studied. In conclusion, repeated exposure to O3 alters the regulation of the antioxidant and inflammatory response in the substantia nigra and the intestine. This indicates that these factors are critical in the loss of regulation in the inflammatory response; they respond to ozone pollution, which can occur in chronic degenerative diseases.

Spatio-temporal evaluation of air pollution using ground-based and satellite data during COVID-19 in Ecuador.

The concentration of gases in the atmosphere is a topic of growing concern due to its effects on health, ecosystems etc. Its monitoring is commonly carried out through ground stations which offer high precision and temporal resolution. However, in countries with few stations, such as Ecuador, these data fail to adequately describe the spatial variability of pollutant concentrations. Remote sensing data have great potential to solve this complication. This study evaluates the spatiotemporal distribution of nitrogen dioxide (NO2) and ozone (O3) concentrations in Quito and Cuenca, using data obtained from ground-based and Sentinel-5 Precursor mission sources during the years 2019 and 2020. Moreover, a Linear Regression Model (LRM) was employed to analyze the correlation between ground-based and satellite datasets, revealing positive associations for O3 (R2 = 0.83, RMSE = 0.18) and NO2 (R2 = 0.83, RMSE = 0.25) in Quito; and O3 (R2 = 0.74, RMSE = 0.23) and NO2, (R2 = 0.73, RMSE = 0.23) for Cuenca. The agreement between ground-based and satellite datasets was analyzed by employing the intra-class correlation coefficient (ICC), reflecting good agreement between them (ICC ≥0.57); and using Bland and Altman coefficients, which showed low bias and that more than 95% of the differences are within the limits of agreement. Furthermore, the study investigated the impact of COVID-19 pandemic-related restrictions, such as social distancing and isolation, on atmospheric conditions. This was categorized into three periods for 2019 and 2020: before (from January 1st to March 15th), during (from March 16th to May 17th), and after (from March 18th to December 31st). A 51% decrease in NO2 concentrations was recorded for Cuenca, while Quito experienced a 14.7% decrease. The tropospheric column decreased by 27.3% in Cuenca and 15.1% in Quito. O3 showed an increasing trend, with tropospheric concentrations rising by 0.42% and 0.11% for Cuenca and Quito respectively, while the concentration in Cuenca decreased by 14.4%. Quito experienced an increase of 10.5%. Finally, the reduction of chemical species in the atmosphere as a consequence of mobility restrictions is highlighted. This study compared satellite and ground station data for NO2 and O3 concentrations. Despite differing units preventing data validation, it verified the Sentinel-5P satellite's effectiveness in anomaly detection. Our research's value lies in its applicability to developing countries, which may lack extensive monitoring networks, demonstrating the potential use of satellite technology in urban planning.

Enhanced Power Generation Using a Dual-Surface-Modified Hematite Photoanode in a Direct Glyphosate Photo Fuel Cell.

Given the current and escalating global energy and environmental concerns, this work explores an innovative approach to mitigate a widely employed commercial herbicide using a direct glyphosate (Gly) photocatalytic fuel cell (PFC). The device generates power continuously by converting solar radiation, degrading and mineralizing commercial glyphosate-based fuel, and reducing sodium persulfate at the cathode. Pristine and modified hematite photoanodes were coupled to Pt/C nanoparticles dispersed in a carbon paper (CP) support (Pt/C/CP) dark cathode by using an H-type cell. The Gly/persulfate PFC shows a remarkable current and power generation enhancement after dual-surface modification of pristine hematite with segregated Hf and FeNiOx cocatalysts. The optimized photoanode elevates maximum current density (Jmax) from 0.35 to 0.71 mA cm-2 and maximum power generation (Pmax) from 0.04 to 0.065 mW cm-2, representing 102.85 and 62.50% increase in Jmax and Pmax, respectively, as compared to pristine hematite. The system demonstrated stability over a studied period of 4 h; remarkably, the photodegradation of Gly proved substantial, achieving ∼98% degradation and ∼6% mineralization. Our findings may significantly contribute to reducing Gly's environmental impact in agribusiness since it may convert the pollutant into energy at zero bias. The proposed device offers a sustainable solution to counteract Gly pollution while concurrently harnessing solar energy for power generation.

Influence of Fast Drying on the Morphology of α-Fe2O3 and FeMnO3/α-Fe2O3 Fibers Produced by Solution Blow Spinning.

α-Fe2O3 and FeMnO3/α-Fe2O3 fibers were successfully prepared via Solution Blow Spinning (SBS). The effect of drying during the SBS process on fiber morphology was evaluated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N2 adsorption-desorption isotherms. A slow drying promoted continuous fibers with rough surfaces and lower average diameters. However, fast drying enabled the production of fibers with low densification and many surface pores with higher BET-specific surface areas. The porous fibers produced have potential applications in energy generation and storage.

Numerical analysis of the mechanical behavior of ceramic dental implants based on Ce-TZP/Al2O3 composite.

This study aimed to identify the potential use of the ceramic composite ZrO2(CeO2)-Al2O3 as a dental implant due to its intrinsic geometry and different masticatory loads based on finite element simulations. Ceramic samples were sintered at 1500 °C-2h, and characterized: The mechanical properties of the ceramic composite (hardness, fracture toughness, flexural strength, Young's Modulus, and Poisson ratio) were determined, in addition to the relative density and its structural characteristics. Commercial dental implant designs (incisal and third-molar) on CAD models were used in this study as an initial implant geometry applied in a typical simulated mandible anatomy. Finite element models were generated for implant geometries using CAD and CAE techniques. Loading cases were considered based on different intensities (100-500 N) and orientation angles to the implant axis (0° and 45°) to reproduce human masticatory conditions. For comparison purposes, the numerical predictions were compared with finite element simulations of gold-standard titanium implants. Ce-TZP/Al2O3 sintered ceramics showed flexural strength of 952.6 ± 88 MPa, hardness and fracture toughness of 1427 ± 46 HV and 11.3 ± 0.4 MPa m1/2, respectively, beside Young's modulus of 228.3 ± 65 GPa and Poisson ratio of 0.28. For both Ce-TZP/Al2O3 dental implant geometries, the implant prototypes showed adequate mechanical behavior regardless of the masticatory load value or the orientation angle applied in the simulations: All finite element predictions are lower than the values established by Mohr Coulomb's failure criterion, allowing the feasibility, preliminarily, of the proposed ceramics for dental implant applications without fracture risk.

Cultural relevance of fine motor domain of the ASQ in Guatemala.

Previous research suggests that the Ages and Stages Questionnaire-3rd ed. (ASQ) fine motor domain (FMD) may not be culturally relevant for developmental screening in a rural Guatemalan community, as the FMD accounts for 40% of all abnormal screenings after a needs assessment in this community. We hypothesize this is due to a lack of exposure to objects assessed in the questionnaire, such as blocks or light switches. The FMD scores of rural Guatemalan children (n = 56) participating in a child development program were compared with Spanish- and English-speaking Latinx-American children attending a US primary care clinic and screened at yearly well-child checks. Groups were matched for age gender, and socioeconomic status. Item-level analyses explored differences across the three groups. In the Guatemalan sample, the FMD abnormal score rates were 16%, 62%, and zero in the 12-, 24-, and 36-month-old children, respectively. Abnormal scores for the Guatemalan sample on the 24-month ASQ-3 significantly differed (p = .01) when compared to the Latinx-American groups. The 24-month questionnaire has more questions about objects than the 12- and 36-month questionnaires, which may explain the higher rates of abnormal scores. Developmental screening with ASQ-3 may not adequately capture the skills of children in similar communities.

La investigación previa ha sugerido que el dominio de motricidad fina (FMD) del Cuestionario de Edades y Etapas - Tercera edición (ASQ) pudiera no ser culturalmente relevante para examinar el desarrollo en una comunidad rural de Guatemala, ya que el FMD representa el 40% de todas las examinaciones anormales después de la evaluación de necesidades en esta comunidad. Nuestra hipótesis es que esto se debe a la falta de exposición a objetos evaluados en el cuestionario, tales como bloques o interruptores de luz. Se compararon los puntajes del FMD de niños de áreas rurales en Guatemala (n=56) que participan en un programa de desarrollo del niño con niños norteamericanos latin-x hablantes del español y del inglés, quienes asisten a una clínica de cuidado primario y son examinados en chequeos anuales de rutina para niños sanos. Se clasificaron los grupos según la edad, el género y la condición económica. Los análisis del nivel de cada punto exploraron las diferencias a lo largo de los 3 grupos. En el grupo muestra de Guatemala, los índices de puntajes anormales de FMD fueron 16%, 62% y cero en los niños de 12, 24 y 36 meses de edad, respectivamente. Los puntajes anormales para el grupo de Guatemala en el ASQ-3 a los 24 meses significativamente difirieron (p=0.01) cuando se les comparó con los grupos muestras norteamericanos latin-x. El cuestionario para la edad de 24 meses tiene más preguntas acerca de objetos que los cuestionarios para las edades de 12 y 36 meses, lo cual pudiera explicar los más altos índices de puntajes anormales. La examinación del desarrollo con ASQ-3 pudiera no captar adecuadamente las destrezas de niños en comunidades similares.

Les recherches précédentes suggèrent que le domaine de la motricité fine (FMD en anglais) du Questionnaire des Ages et des Etapes - 3e édition (ASQ en anglais) pourrait ne pas être pertinent sur le point culturel pour le dépistage développemental dans une communauté rurale du Guatémala puisque le FMD explique 40% de tous les dépistages anormaux après une évaluation des besoins dans cette communauté. Nous émettons l'hypothèse que cela est dû au manque d'exposition à des objets évalués dans le questionnaire, comme des blocs ou des interrupteurs (électricité). Les scores de FMD d'enfants de milieu rural au Guatémala (n=56) participant à un programme de développement de l'enfant ont été comparés à ceux d'enfants Latinx-Américains parlant espagnol et anglais, patients d'une clinique de soins primaires aux Etats-Unis d'Amérique et dépisté avec des contrôles de santé annuels. Les groupes ont été assortis par groupe de genre et de statut socioéconomique. Des analyses de précision ont exploré les différences entre les 3 groupes. Dans l'échantillon du Guatémala les taux de score anormal FMD étaient de 16%, 62% et zéro chez les enfants de 12, 24 et 36 mois, respectivement. Les scores anormaux pour l'échantillon du Guatémala pour le ASQ-3 à 24 moi a différé de manière importante (p=0.01) lors de la comparaison aux groupes Latinx-Américains. Le questionnaire de 24 mois a plus de questions sur les objets que les questionnaires de 12 mois et de 36 mois, ce qui peut expliquer les taux plus élevés de scores anormaux. Le dépistage développemental avec le ASQ-3 pourrait s'avérer ne pas capturer de manière adéquate les compétences des enfants dans des communautés similaires.

Analysis of the photocatalytic activity of La0.9Sr0.1Fe0.8Co0.2O3±Î´ perovskite as a catalyst in the degradation of RB-5 dye.

The photocatalytic efficiency of some semiconductors depends mainly on their morphological, optical, and structural properties, which can be modified by varying the calcination temperature. In order to evaluate how these properties change, as a function of temperature in a AA'BB'O3 perovskite material, La0.9Sr0.1Fe0.8Co0.2O3±Î´ (LSFC) was synthesized by the Pechini method and calcined at different temperatures (600 °C, 700 °C, 800 °C, and 900 °C). All the samples were characterized structurally, morphologically, and optically by XRD, SEM, and UV-Vis spectroscopy. Additionally, specific surface area and pore size distribution were calculated by BET and BHJ methods. LSFC was evaluated as photocatalyst material, estimating the degradation of reactive black 5 (RB5), employing as irradiation source UV light and sunlight. The obtained results display a clear tendency between the photoactivity and the heat treatment: degradation percentage decreases as the calcination temperature increases mainly due to the crystal and grain size and, furthermore, loss of porosity and the decrease in surface area, affecting the photocatalytic activity (98%, 95%, 74%, and 50% degradation, respectively). All the ceramic samples follow a pseudo-first-order reaction.

Augmented degradation of dyed organic pollutant using Fe2O3 supported on char formed from poultry slaughterhouse waste.

In this work, a novel support for an iron-based catalyst was prepared and employed for Ponceau 4R degradation by photo-Fenton reaction. To this, poultry waste was used for producing char, which was subsequently used to prepare the Fe2O3/Char composite. Process parameters, including catalyst dosage, pH, and hydrogen peroxide concentration, were investigated. The characterization analysis indicated that the textural properties of the composite were improved after impregnation with Fe2O3. The composite exhibited excellent catalytic activity, achieving a decolorization efficiency of 97% at 45 min and 81.06% organic carbon removal at 300 min. In addition, the material showed acceptable performance after four consecutive cycles. Furthermore, a scavenger test was performed to investigate the major reactive species involved in the Ponceau 4R oxidation, and a plausible mechanism for the respective reaction was projected. Therefore, the results of this research demonstrate that this material can be used as a potential catalyst for the abatement of dyed molecules from wastewater.

Risk factors associated with higher scores in internalizing and externalizing behaviors in Chilean preschoolers.

Early detection of behavioral disorders in children is necessary for intervention. Available data show a high prevalence of child and adolescent psychiatric disorders in Chile (22.5%), but behavioral problems in younger children have not been evaluated. This work assesses behavioral disorders in preschoolers and their association with sociodemographic variables of the family and the child. The data was collected during the impact assessment of the Biopsychosocial Development Support Program "Chile Crece Contigo", using a multistage and representative random sample of 1377 preschoolers, aged between 30 and 48 months, who attended public health services. Homes were visited to apply a questionnaire and the Child Behavior Checklist (CBCL, 1.5-5 years). Results: Multivariable regression model for total raw scores shows that child's age, the number of chronic diseases in the child, and history of exposure to mother's alcohol consumption in pregnancy, remain significant when adjusted for all variables included (R2 of 17.8% and η2 of .19 (95% CI: .14-.22)). In externalizing and internalizing explanatory models, child's chronic diseases and a higher score of authoritarian beliefs about parenting show the two largest effect sizes. These results add to the evidence of urgent problems in preschool mental health.

La temprana detección de trastornos de comportamiento en los niños es necesaria para la intervención. La información disponible muestra una alta prevalencia de trastornos siquiátricos de niños y adolescentes en Chile (22.5%), pero no se han evaluado los problemas de comportamiento en niños más pequeños. Este trabajo evalúa trastornos de comportamiento en niños de edad prescolar y su asociación con variables sociodemográficas de la familia y del niño. La información se recogió durante la evaluación del impacto del Programa de Apoyo al Desarrollo Biosicosocial "Chile Crece Contigo," usando un grupo muestra de multiniveles representativo de 1,377 niños prescolares, de entre 30 y 48 meses de edad, quienes recibían servicios de salud pública. Se visitaron las casas para dar un cuestionario y la Lista de Comprobación del Comportamiento del Niño (CGCL, 1.5-5 años). Resultados: El modelo de regresión de variables múltiples para el total de la puntuación en bruto muestra que la edad del niño, el número de enfermedades crónicas en el niño, así como el historial de exposición al consumo de alcohol por parte de la madre durante el embarazo permanecen siendo significativos cuando se les ajusta para todas las variables incluidas (R2 de 17.8% y η2 de 0.19 (95% CI 0.14 a 0.22)). En los modelos explicativos de externalización e internalización, las enfermedades crónicas del niño y un más alto puntaje de creencias autoritarias acerca de la crianza demuestran ser las dos con la magnitud de efectos más extensa. Estos resultados contribuyen aun más a la evidencia sobre los problemas urgentes en la salud mental prescolar.

La détection précoce de troubles du comportement chez les enfants est nécessaire afin d'intervenir. Les données disponibles font état d'une forte prévalence de troubles psychiatrique de l'enfant et de l'adolescent au Chili (22,5%) mais les problèmes de comportement chez les plus jeunes enfants ne sont pas évalués. Ce travail évalue les troubles du comportement chez des enfants d'âge préscolaire et leur lien aux variables sociodémographiques de la famille et de l'enfant. Les données ont été recueillies durant l'évaluation de l'impact du programme de Soutien au Développement Biopsychosocial « Chile Crece Contigo ¼, en utilisant un échantillon aléatoire à plusieurs degrés et représentatif de 1 377 enfants d'âge préscolaire, âgés de 30 à 48 mois, qui participaient à des services de santé publique. Les domiciles ont été visités pour appliquer un questionnaire et la Checklist de Comportement de l'Enfant (CBCL, 1,5-5 ans). Résultats: Le modèle de régression multivariable pour les scores bruts totaux montre que l'âge de l'enfant, le nombre de maladies chroniques chez l'enfant et le passé d'exposition à la consommation d'alcool de la mère durant la grossesse restent importants après l'ajustement pour toutes le variables inclues (R2 de 17,8% and η2 de 0,19 (95% CI 0.14 à 0.22)). Dans les modèles explicatifs externalisant et internalisant les maladies chroniques de l'enfant et un score élevé de croyances autoritaire sur le parentage font preuves des plus grands effets de taille. Ces résultats s'ajoutent aux preuves sur les problèmes urgents de santé mentale préscolaire.

Effect of green Fe2O3 nanoparticles in controlling Fusarium fruit rot disease of loquat in Pakistan.

The subtropical fruit known as the loquat is prized for both its flavour and its health benefits. The perishable nature of loquat makes it vulnerable to several biotic and abiotic stressors. During the previous growing season (March-April 2021), loquat in Islamabad showed signs of fruit rot. Loquat fruits bearing fruit rot symptoms were collected, and the pathogen that was causing the disease isolated and identified using its morphology, microscopic visualisation, and rRNA sequence. The pathogen that was isolated was identified as Fusarium oxysporum. Green synthesized metallic iron oxide nanoparticles (Fe2O3 NPs) were employed to treat fruit rot disease. Iron oxide nanoparticles were synthesized using a leaf extract of the Calotropis procera. Characterization of NPs was performed by different modern techniques. Fourier transform infrared spectroscopy (FTIR) determined the existence of stabilizing and reducing compounds like phenol, carbonyl compounds, and nitro compounds, on the surface of Fe2O3 NPs. X-ray diffraction (XRD) explained the crystalline nature and average size (~49 nm) of Fe2O3 NPs. Energy dispersive X-ray (EDX) exhibited Fe and O peaks, and scanning electron microscopy (SEM) confirmed the smaller size and spherical shape of Fe2O3 NPs. Following both in vitro and in vivo approaches, the antifungal potential of Fe2O3 NPs was determined, at different concentrations. The results of both in vitro and in vivo analyses depicted that the maximum fungal growth inhibition was observed at concentration of 1.0 mg/mL of Fe2O3 NPs. Successful mycelial growth inhibition and significantly reduced disease incidence suggest the future application of Fe2O3 NPs as bio fungicides to control fruit rot disease of loquat.

Insights into the Fe3+ Doping Effects on the Structure and Electron Distribution of Cr2O3 Nanoparticles.

Herein, we carefully investigated the Fe3+ doping effects on the structure and electron distribution of Cr2O3 nanoparticles using X-ray diffraction analysis (XRD), maximum entropy method (MEM), and density functional theory (DFT) calculations. We showed that increasing the Fe doping induces an enlargement in the axial ratio of c/a, which is associated with an anisotropic expansion of the unit cell. We found that as Fe3+ replaces Cr in the Cr2O3 lattice, it caused a higher interaction between the metal 3d states and the oxygen 2p states, which led to a slight increase in the Cr/Fe-O1 bond length followed by an opposite effect for the Cr/Fe-O2 bonds. Our results also suggest that the excitations characterize a well-localized bandgap region from occupied Cr d to unoccupied Fe d states. The Cr2O3 and Fe-doped Cr2O3 nanoparticles behave as Mott-Hubbard insulators due to their band gap being in the d-d gap, and Cr 3d orbitals dominate the conduction band. These findings suggest that the magnitude and the character of the electronic density near the O atom bonds in Cr2O3 nanoparticles are modulated by the Cr-Cr distances until its stabilization at the induced quasi-equilibrium of the Cr2O3 lattice when the Fe3+ doping values reaches the saturation level range.

Molecular Dynamics Approach to the Physical Mixture of In2O3 and ZrO2: Defect Formation and Ionic Diffusion.

Recent research on the use of physical mixtures In2O3-ZrO2 has raised interesting questions as to how their combination enhances catalytic activity and selectivity. Specifically, the relationship between oxygen diffusion and defect formation and the epitaxial tension in the mixture should be further investigated. In this study, we aim to clarify some of these relationships through a molecular dynamics approach. Various potentials for the two oxides are compared and selected to describe the physical mixture of In2O3 and ZrO2. Different configurations of each single crystal and their physical mixture are simulated, and oxygen defect formation and diffusion are measured and compared. Significant oxygen defect formation is found in both crystals. In2O3 seems to be stabilized by the mixture, while ZrO2 is destabilized. Similar results were found for the ZrO2 doping with In and ln2O3 doping with Zr. The results explain the high activity and selectivity catalyst activity of the mixture for the production of isobutylene from ethanol.

Study of the oxidation process of bismuth nanoparticles using NaClO.

Bismuth nanoparticles (NPs) colloids synthesized in deionized water by laser ablation of solids in liquids technique (LASL) were oxidized using NaClO solutions at different concentrations. Oxidized nanomaterials were characterized using several techniques. The crystalline phases of the bismuth compound were determined using Raman microspectroscopy, and the crystallographic structure was identified by x-ray diffraction (XRD). The size and morphology of the obtained nanomaterials were studied by transmission electron microscopy (TEM). The chemical states were determined using x-ray photoelectron spectroscopy (XPS), and the optical properties of the colloids were characterized by UV-vis spectroscopy. The absorption spectra were analyzed using the Tauc method to determine the band gaps of the obtained nanomaterials. Our results showed morphological changes, starting from small nanoparticles to nanosheets and a mixture of nanosheets with hollow nanoparticles. Two kinds of nanomaterials were found depending on the NaClO solution concentration: Bi2O2CO3single phase and a mixture ofδ-Bi2O3and Bi2O2CO3. Some samples were tested as photocatalysts and showed good performance in the degradation of methylene blue in solution. To the best of our knowledge, this is the first study on the oxidation process of bismuth colloidal nanoparticles at room temperature.

Inhibitory effects of diarsenic trioxide (As2O3) on hepatocellular carcinoma cells exerted by regulation of promyelocytic leukemia protein levels

Previous Chinese research revealed that diarsenic trioxide (As2O3) inhibits acute promyelocytic leukemia (PML) cell proliferation and initiates apoptosis through degradation of the PML-retinoic acid receptor protein. This study was to analyse whether As2O3 also had an effect on hepatocellular carcinoma (HCC) cells. As2O3 effects on various HCC cell lines and primary HCC cells were investigated in time and dose series, including measurements of cell growth, PML mRNA and protein expression, xenografted tumor formation, and the self-renewal Oct4 and hepatocyte marker expressions in mouse model xenografts or cells treated with PML siRNA. The results were analyzed by immunocytochemistry, quantitative reverse transcription PCR and western blotting as well as indocyanine green and Periodic Acid Schiff staining. As2O3 inhibited HCC cell and HCC cell-derived xenograft tumor formation in a time-dependent manner and reduced PML protein expression in HCC cells, but had limited effects on PML mRNA levels in cell nuclei. The HCC cell line HuH7 treated with As2O3 showed a decreased expression of alpha-fetoprotein and increased expression and transcription of mature hepatocyte markers, indicating differentiation of HCC cells into hepatocytes. Cytokeratin 18 protein and mRNA levels as well as tyrosine aminotransferase and apolipoprotein B mRNA transcriptions were enhanced by As2O3 as were the numbers of indocyanine green and Periodic Acid Schiff stained cells. In addition, As2O3 downregulated the expression of Oct4. In conclusion, since As2O3 inhibited HCC cell proliferation and HCC cell-derived xenograft tumor formation it is suggested that an appropriate concentration of As2O3 might be a promising therapy to treat HCC.

Alumina as an Antifungal Agent for Pinus elliottii Wood.

This work deals with the durability of a Pinus elliotti wood impregnated with alumina (Al2O3) particles. The samples were impregnated at three different Al2O3 weight fractions (c.a. 0.1%, 0.3% and 0.5%) and were then exposed to two wood-rot fungi, namely white-rot fungus (Trametes versicolor) and brown-rot fungus (Gloeophyllum trabeum). Thermal and chemical characteristics were evaluated by Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric (TG) analyses. The wood which incorporated 0.3 wt% of Al2O3 presented a weight loss 91.5% smaller than the untreated wood after being exposed to the white-rot fungus. On the other hand, the highest effectiveness against the brown-rot fungus was reached by the wood treated with 5 wt% of Al2O3, which presented a mass loss 91.6% smaller than that of the untreated pine wood. The Al2O3-treated woods presented higher antifungal resistances than the untreated ones in a way that: the higher the Al2O3 content, the higher the thermal stability. In general, the impregnation of the Al2O3 particles seems to be a promising treatment for wood protection against both studied wood-rot fungi. Additionally, both FT-IR and TG results were valuable tools to ascertain chemical changes ascribed to fungal decay.

Comparative Colorimetric Sensor Based on Bi-Phase γ-/α-Fe2O3 and γ-/α-Fe2O3/ZnO Nanoparticles for Lactate Detection.

This work reports on Fe2O3 and ZnO materials for lactate quantification. In the synthesis, the bi-phase γ-/α-Fe2O3 and γ-/α-Fe2O3/ZnO nanoparticles (NPs) were obtained for their application in a lactate colorimetric sensor. The crystalline phases of the NPs were analyzed by XRD and XPS techniques. S/TEM images showed spheres with an 18 nm average and a needle length from 125 to 330 nm and 18 nm in diameter. The γ-/α-Fe2O3 and γ-/α-Fe2O3/ZnO were used to evaluate the catalytic activity of peroxidase with the substrate 3,3,5,5-tetramethylbenzidine (TMB), obtaining a linear range of 50 to 1000 µM for both NPs, and a 4.3 µM and 9.4 µM limit of detection (LOD), respectively. Moreover, γ-/α-Fe2O3 and γ-/α-Fe2O3/ZnO/lactate oxidase with TMB assays in the presence of lactate showed a linear range of 50 to 1000 µM, and both NPs proved to be highly selective in the presence of interferents. Finally, a sample of human serum was also tested, and the results were compared with a commercial lactometer. The use of ZnO with Fe2O3 achieved a greater response toward lactate oxidation reaction, and has implementation in a lactate colorimetric sensor using materials that are economically accessible and easy to synthesize.

Synthesis and Characterization of α-Al2O3/Ba-ß-Al2O3 Spheres for Cadmium Ions Removal from Aqueous Solutions.

The search for adsorbent materials with a certain chemical inertness, mechanical resistance, and high adsorption capacity, as is the case with alumina, is carried out with structural or surface modifications with the addition of additives or metallic salts. This research shows the synthesis, characterization, phase evolution and Cd(II) adsorbent capacity of α-Al2O3/Ba-ß-Al2O3 spheres obtained from α-Al2O3 nanopowders by the ion encapsulation method. The formation of the Ba-ß-Al2O3 phase is manifested at 1500 °C according to the infrared spectrum by the appearance of bands corresponding to AlO4 bonds and the appearance of peaks corresponding to Ba-O bonds in Raman spectroscopy. XRD determined the presence of BaO·Al2O3 at 1000 °C and the formation of Ba-ß-Al2O3 at 1600 °C. Scanning electron microscopy revealed the presence of spherical grains corresponding to α-Al2O3 and hexagonal plates corresponding to ß-Al2O3 in the spheres treated at 1600 °C. The spheres obtained have dimensions of 4.65 ± 0.30 mm in diameter, weight of 43 ± 2 mg and a surface area of 0.66 m2/g. According to the curve of pH vs. zeta potential, the spheres have an acid character and a negative surface charge of -30 mV at pH 5. Through adsorption studies, an adsorbent capacity of Cd(II) of 59.97 mg/g (87 ppm Cd(II)) was determined at pH 5, and the data were fitted to the pseudo first order, pseudo second order and Freundlich models, with correlation factors of 0.993, 0.987 and 0.998, respectively.