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3.
Chem Sci ; 15(17): 6454-6464, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38699272

RESUMEN

Supported noble metal catalysts, ubiquitous in chemical technology, often undergo dynamic transformations between reduced and oxidized states-which influence the metal nuclearities, oxidation states, and catalytic properties. In this investigation, we report the results of in situ X-ray absorption spectroscopy, scanning transmission electron microscopy, and other physical characterization techniques, bolstered by density functional theory, to elucidate the structural transformations of a set of MgO-supported palladium catalysts under oxidative treatment conditions. As the calcination temperature increased, the as-synthesized supported metallic palladium nanoparticles underwent oxidation to form palladium oxides (at approximately 400 °C), which, at approximately 500 °C, were oxidatively fragmented to form mixtures of atomically dispersed palladium cations. The data indicate two distinct types of atomically dispersed species: palladium cations located at MgO steps and those embedded in the first subsurface layer of MgO. The former exhibit significantly higher (>500 times) catalytic activity for ethylene hydrogenation than the latter. The results pave the way for designing highly active and stable supported palladium hydrogenation catalysts with optimized metal utilization.

4.
Podium (Pinar Río) ; 19(1)abr. 2024.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1550631

RESUMEN

La unión de la teoría y la práctica es crucial para una enseñanza equitativa, además se requiere de estrategias flexibles y efectivas para asegurar la inclusión. El objetivo de este artículo fue proponer estrategias para la participación de estudiantes con discapacidad en las clases de Educación Física. Se revisaron 22 trabajos centrados en estrategias de inclusión para Educación Física en las bases de datos SciELO, Google Académico y Dialnet. A partir de los resultados obtenidos, se procedió a la sistematización y se diseñaron estrategias para mejorar la experiencia de aprendizaje y promover la igualdad, entre ellas las que se adaptan al currículo y actividades; las de formación y sensibilización docente; y, las de cultura inclusiva y ambiente positivo. Se concluye que la inclusión educativa es un proceso complejo que demanda cambios en actitudes, metodologías y políticas educativas.


O casamento entre teoria e prática é crucial para o ensino equitativo, e são necessárias estratégias flexíveis e eficazes para garantir a inclusão. O objetivo deste artigo foi propor estratégias para a participação de alunos com deficiência nas aulas de educação física. Vinte e dois artigos com foco em estratégias de inclusão para a Educação Física foram revisados nas bases de dados SciELO, Google Scholar e Dialnet. Com base nos resultados obtidos, foram sistematizadas e elaboradas estratégias para melhorar a experiência de aprendizagem e promover a igualdade, incluindo aquelas adaptadas ao currículo e às atividades; treinamento e conscientização dos professores; e cultura inclusiva e ambiente positivo. Conclui-se que a inclusão educacional é um processo complexo que exige mudanças de atitudes, metodologias e políticas educacionais.


The union of theory and practice is crucial for equitable teaching, and flexible and effective strategies are required to ensure inclusion. The objective of this article was to propose strategies for the participation of students with disabilities in Physical Education classes. Twenty-two works focused on inclusion strategies for Physical Education were reviewed in the SciELO, Google Academic and Dialnet databases. Based on the results obtained, the systematization was carried out and strategies were designed to improve the learning experience and promote equality, including those that adapt to the curriculum and activities; those of teacher training and awareness; and, those with an inclusive culture and positive environment. It is concluded that educational inclusion is a complex process that demands changes in attitudes, methodologies and educational policies.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38552312

RESUMEN

OBJECTIVE: To investigate the risk of DM and evaluate the impact of SLE therapies on the risk of developing DM in patients with SLE. METHODS: Electronic database searches of PubMed, Embase, Cochrane Library, and Web of Science were performed from inception to February 2023. Cohort and cross-sectional studies that analyzed the risk of DM in patients with SLE were included. The associations between diabetes and antirheumatic agents, such as antimalarials and glucocorticoids, were analyzed in cohort studies. Data were pooled using fixed- or random-effects meta-analysis to estimate pooled odd ratios (OR), relative risks (RR), and 95% confidence intervals (CIs). This study was registered with PROSPERO (CRD42023402774). RESULTS: A total of 37 studies (23 cross-sectional and 14 cohort studies) involving 266 537 patients with SLE were included. The pooled analyses from cross-sectional studies and cohort studies did not show an increased risk of DM in SLE patients (OR = 1.05, 95% CI 0.87-1.27; p = 0.63 and RR = 1.32, 95% CI 0.93-1.87; p= 0.12, respectively). However, several cohort studies consistently demonstrated a reduced risk of diabetes with antimalarials, while glucocorticoid use has been associated with an increased risk of developing diabetes. Age, sex, hypertension, and immunosuppressants have not been identified as risk factors for DM in SLE patients. CONCLUSIONS: Although there was no increased risk of DM in patients with SLE compared with controls, HCQ users or adherents had a decreased risk, whereas glucocorticoid users had an increased risk.

6.
J Phys Chem C Nanomater Interfaces ; 128(3): 1165-1176, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38293693

RESUMEN

Soft-oxidant-assisted methane coupling has emerged as a promising pathway to upgrade methane from natural gas sources to high-value commodity chemicals, such as ethylene, at selectivities higher than those associated with oxidative (O2) methane coupling (OCM). To date, few studies have reported investigations into the electronic structure and the microscopic physical structure of catalytic active sites present in the binary metal oxide catalyst systems that are known to be effective for this reaction. Correlating the catalyst activity to specific active site structures and electronic properties is an essential aspect of catalyst design. Here, we used X-ray absorption spectroscopy at the Ca K-edge to ascertain the most probable local environment of Ca in the ZnO-supported Ca oxide catalysts. These catalysts are shown here to be active for N2O-assisted methane coupling (N2O-OCM) and have previously been reported to be active for CO2-assisted methane coupling (CO2-OCM). X-ray absorption near edge structure features at multiple Ca loadings are interpreted through simulated spectra derived from ab initio full multiple scattering calculations. These simulations included consideration of CaO structures organized in multiple spatial arrangements-linear, planar, and cubic-with separate analyses of Ca atoms in the surfaces and bulk of the three-dimensional structures. The morphology of the oxide clusters was found to influence the various regions of the X-ray absorption spectrum differently. Experiment and theory show that for low-Ca-loading catalysts (≤1 mol %), which contain sites particularly active for methane coupling, Ca primarily exists in an oxidized state that is consistent with the coordination environment of Ca ions in one- and two-dimensional clusters. In addition to their unique nanoscale structures, the spectra also indicate that these clusters have varying degrees of undercoordinated surface Ca atoms that could further influence their catalytic activities. The local Ca structure was correlated to methane coupling activity from N2O-OCM and previously reported CO2-OCM reactor studies. This study provides a unique perspective on the relationship between the catalyst physical and electronic structure and active sites for soft-oxidant-assisted methane coupling, which can be used to inform future catalyst development.

7.
Pediatr Res ; 95(2): 566-572, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38057577

RESUMEN

BACKGROUND: Studies examining the association between in utero Zika virus (ZIKV) exposure and child neurodevelopmental outcomes have produced varied results. METHODS: We aimed to assess neurodevelopmental outcomes among normocephalic children born from pregnant people enrolled in the Zika in Pregnancy in Honduras (ZIPH) cohort study, July-December 2016. Enrollment occurred during the first prenatal visit. Exposure was defined as prenatal ZIKV IgM and/or ZIKV RNA result at enrollment. Normocephalic children, >6 months old, were selected for longitudinal follow-up using the Bayley Scales of Infant and Toddler Development (BSID-III) and the Ages & Stages Questionnaires: Social-Emotional (ASQ:SE-2). RESULTS: One hundred fifty-two children were assessed; after exclusion, 60 were exposed and 72 were unexposed to ZIKV during pregnancy. Twenty children in the exposed group and 21 children in the unexposed group had a composite score <85 in any of the BSID-III domains. Although exposed children had lower cognitive and language scores, differences were not statistically significant. For ASQ:SE-2 assessment, there were not statistically significant differences between groups. CONCLUSIONS: This study found no statistically significant differences in the neurodevelopment of normocephalic children between in utero ZIKV exposed and unexposed. Nevertheless, long-term monitoring of children with in utero ZIKV exposure is warranted. IMPACT: This study found no statistically significant differences in the neurodevelopment in normocephalic children with in utero Zika virus exposure compared to unexposed children, although the exposed group showed lower cognitive and language scores that persisted after adjustment by maternal age and education and after excluding children born preterm and low birth weight from the analysis. Children with prenatal Zika virus exposure, including those normocephalic and have no evidence of abnormalities at birth, should be monitored for neurodevelopmental delays. Follow-up is important to be able to detect developmental abnormalities that might not be detected earlier in life.


Asunto(s)
Craneosinostosis , Complicaciones Infecciosas del Embarazo , Efectos Tardíos de la Exposición Prenatal , Infección por el Virus Zika , Virus Zika , Embarazo , Lactante , Recién Nacido , Femenino , Humanos , Estudios de Cohortes , Infección por el Virus Zika/diagnóstico , Desarrollo Infantil
8.
Angew Chem Int Ed Engl ; 63(1): e202313389, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-37906130

RESUMEN

Tuning the anionic site of catalyst supports can impact reaction pathways by creating active sites on the support or influencing metal-support interactions when using supported metal nanoparticles. This study focuses on CO2 hydrogenation over supported Cu nanoparticles, revealing a 3-fold increase in methanol yield when replacing oxygen anions with hydrides in the perovskite support (Cu/BaTiO2.8 H0.2 yields ~146 mg/h/gCu vs. Cu/BaTiO3 yields ~50 mg/h/gCu). The contrast suggests that significant roles are played by the support hydrides in the reaction. Temperature programmed reaction and isotopic labelling studies indicate that BaTiO2.8 H0.2 surface hydride species follow a Mars van Krevelen mechanism in CO2 hydrogenation, promoting methanol production. High-pressure steady-state isotopic transient kinetic analysis (SSITKA) studies suggest that Cu/BaTiO2.8 H0.2 possesses both a higher density and more active and selective sites for methanol production compared to Cu/BaTiO3 . An operando high-pressure diffuse reflectance infrared spectroscopy (DRIFTS)-SSITKA study shows that formate species are the major surface intermediates over both catalysts, and the subsequent hydrogenation steps of formate are likely rate-limiting. However, the catalytic reactivity of Cu/BaTiO2.8 H0.2 towards the formate species is much higher than Cu/BaTiO3 , likely due to the altered electronic structure of interface Cu sites by the hydrides in the support as validated by density functional theory (DFT) calculations.

9.
Biomedica ; 43(4): 492-505, 2023 12 01.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38109136

RESUMEN

INTRODUCTION: The frequency of detected strongyloidiasis is affected by the selected laboratory method in the studied population. Considering that Honduras has few community-based studies, the analysis of the laboratory record data can provide information helping to understand this parasitosis. OBJECTIVE: To estimate the frequency and to identify the factors associated with strongyloidiasis, analyzing the laboratory records of the Servicio de Parasitología at Hospital Escuela in Tegucigalpa (Honduras) between 2010 and 2022. MATERIALS AND METHODS: We carried out a descriptive, cross-sectional, analytical study. The laboratory diagnosis consisted of stool samples' examination by direct smear and modified Baermann technique. We estimated frequencies and percentages. The statistical association was calculated with prevalence ratios and a 95% confidence interval. Software R, version 4.2.0, and epiR package, version 2.0.46, were used to perform the analysis. RESULTS: The frequency of strongyloidiasis was 0.29% (112/38,085). It was higher with the modified Baermann technique (0.87%; 40/4,575) among male patients (0.44%; 70/15,758). Regarding the age, strongyloidiasis was higher in the 20-40 years old group (0.41%; 28/6,886) with direct smear and 41-61 years old (1.14%; 14/1,232) group with the modified Baermann technique. Among the factors associated with strongyloidiasis were age between 20 and 61 years old (PR=2.26, CI 95%=1.53-3.31), male patients (PR=2.34, CI 95%=1.60­3.44), mucus (PR=1.86, CI 95%=1.22-2.83) and Charcot-Leyden crystals in stool (PR=8.47, CI 95%=5.14-13.96); watery stool (PR=2.39, CI 95%=1.55-3.68), and other helminthiases (PR=6.73, CI 95%=3.98-11.38). Associated factors to cases detected with the modified Baermann technique were outpatient consultation (PR=4.21, CI 95%=1.91-9.28) and formed stools (PR=3.99, CI 95%=1.94-8.19). CONCLUSIONS: The modified Baermann technique increased the detection of strongyloidiasis almost four times. Most cases were distributed among male adults. The cases diagnosed exclusively with the modified Baermann technique have differences from those with observed larvae in the direct smear. It is necessary to develop community-based population studies.


Introducción: La detección de estrongiloidiasis depende del método de diagnóstico utilizado y la población estudiada. Dado que en Honduras hay pocos estudios poblacionales, el análisis de los datos de laboratorio puede generar información que ayude a entender esta parasitosis. Objetivo: Estimar la frecuencia e identificar los factores asociados a la estrongiloidiasis mediante el análisis de los registros de laboratorio del Servicio de Parasitología del Hospital Escuela en Tegucigalpa (Honduras) durante el periodo 2010-2022. Materiales y métodos: Se llevó a cabo un estudio descriptivo, transversal y analítico. El diagnóstico de laboratorio consistió en el análisis de muestras de heces con los métodos directo y Baermann modificado. Se estimaron frecuencias y porcentajes, y la asociación estadística se calculó con razón de prevalencia e intervalos de confianza del 95 %. Se utilizaron los programas R, versión 4.2.0, y el paquete epiR, versión 2.0.46, para ejecutar los análisis estadísticos. Resultados: La frecuencia general de estrongiloidiasis fue 0,29 % (112/38.085). Dicha frecuencia de detección fue mayor con el método de Baermann modificado (0,87 %; 40/4.575), entre pacientes masculinos (0,44 %; 70/15.758). También fue mayor en el rango de edad 20-40 años (0,41%; 28/6.886) por examen directo y entre los 41-61 años (1,14%; 14/1.232) con el método de Baermann modificado. Entre los factores asociados con la estrongiloidiasis se encontraron: edad entre los 20 y los 61 años (RP=2,26; IC 95%=1,53-3,31), sexo masculino (RP=2,34; IC 95% =1,60-3.44), moco (RP=1,86; IC 95%=1,22-2,83) y cristales de Charcot-Leyden en heces (RP=8,47, IC 95%=5,14-13,96), heces líquidas (RP=2,39, IC 95%=1,55-3,68) y otras helmintiasis (RP=6,73, IC 95%=3,98-11,38). Como factores asociados a los casos detectados con el método de Baermann modificado están consulta externa (RP=4,21, IC 95%=1,91-9,28) y heces formadas (RP=3,99, IC 95%=1,94-8,19). Conclusiones: El método de Baermann modificado aumentó la frecuencia de detección de estrongiloidiasis casi cuatro veces. La mayoría de los casos se distribuyeron entre pacientes masculinos adultos. Los casos diagnosticados exclusivamente con el método de Baermann modificado tuvieron diferencias con los casos diagnosticados por examen directo. Es necesario realizar estudios poblacionales.


Asunto(s)
Estrongiloidiasis , Adulto , Humanos , Masculino , Adulto Joven , Persona de Mediana Edad , Estrongiloidiasis/diagnóstico , Estrongiloidiasis/epidemiología , Centros de Atención Terciaria , Honduras/epidemiología , Estudios Transversales , Laboratorios
10.
Biomédica (Bogotá) ; 43(4)dic. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1533961

RESUMEN

Introduction. The frequency of detected strongyloidiasis is affected by the selected laboratory method in the studied population. Considering that Honduras has few community-based studies, the analysis of the laboratory record data can provide information helping to understand this parasitosis. Objective. To estimate the frequency and to identify the factors associated with strongyloidiasis, analyzing the laboratory records of the Servicio de Parasitología at Hospital Escuela in Tegucigalpa (Honduras) between 2010 and 2022. Materials and methods. We carried out a descriptive, cross-sectional, analytical study. The laboratory diagnosis consisted of stool samples' examination by direct smear and modified Baermann technique. We estimated frequencies and percentages. The statistical association was calculated with prevalence ratios and a 95% confidence interval. Software R, version 4.2.0, and epiR package, version 2.0.46, were used to perform the analysis. Results. The frequency of strongyloidiasis was 0.29% (112/38,085). It was higher with the modified Baermann technique (0.87%; 40/4,575) among male patients (0.44%; 70/15,758). Regarding the age, strongyloidiasis was higher in the 20-40 years old group (0.41%; 28/6,886) with direct smear and 41-61 years old (1.14%; 14/1,232) group with the modified Baermann technique. Among the factors associated with strongyloidiasis were age between 20 and 61 years old (PR=2.26, CI 95%=1.53-3.31), male patients (PR=2.34, CI 95%=1.60-3.44), mucus (PR=1.86, CI 95%=1.22-2.83) and Charcot-Leyden crystals in stool (PR=8.47, CI 95%=5.14-13.96); watery stool (PR=2.39, CI 95%=1.55-3.68), and other helminthiases (PR=6.73, CI 95%=3.98-11.38). Associated factors to cases detected with the modified Baermann technique were outpatient consultation (PR=4.21, CI 95%=1.91-9.28) and formed stools (PR=3.99, CI95% =1.94-8.19). Conclusions. The modified Baermann technique increased the detection of strongyloidiasis almost four times. Most cases were distributed among male adults. The cases diagnosed exclusively with the modified Baermann technique have differences from those with observed larvae in the direct smear. It is necessary to develop community-based population studies.


Introducción. La detección de estrongiloidiasis depende del método de diagnóstico utilizado y la población estudiada. Dado que en Honduras hay pocos estudios poblacionales, el análisis de los datos de laboratorio puede generar información que ayude a entender esta parasitosis. Objetivo. Estimar la frecuencia e identificar los factores asociados a la estrongiloidiasis mediante el análisis de los registros de laboratorio del Servicio de Parasitología del Hospital Escuela en Tegucigalpa (Honduras) durante el periodo 2010-2022. Materiales y métodos. Se llevó a cabo un estudio descriptivo, transversal y analítico. El diagnóstico de laboratorio consistió en el análisis de muestras de heces con los métodos directo y Baermann modificado. Se estimaron frecuencias y porcentajes, y la asociación estadística se calculó con razón de prevalencia e intervalos de confianza del 95 %. Se utilizaron los programas R, versión 4.2.0, y el paquete epiR, versión 2.0.46, para ejecutar los análisis estadísticos. Resultados. La frecuencia general de estrongiloidiasis fue 0,29 % (112/38.085). Dicha frecuencia de detección fue mayor con el método de Baermann modificado (0,87 %; 40/4.575), entre pacientes masculinos (0,44 %; 70/15.758). También fue mayor en el rango de edad 20-40 años (0,41%; 28/6.886) por examen directo y entre los 41-61 años (1,14%; 14/1.232) con el método de Baermann modificado. Entre los factores asociados con la estrongiloidiasis se encontraron: edad entre los 20 y los 61 años (RP=2,26; IC 95%=1,53-3,31), sexo masculino (RP=2,34; IC95%=1,60-3.44), moco (RP=1,86; IC 95%=1,22-2,83) y cristales de Charcot-Leyden en heces (RP=8,47, IC 95%=5,14-13,96), heces líquidas (RP=2,39, IC 95%=1,55-3,68) y otras helmintiasis (RP=6,73, IC 95%=3,98-11,38). Como factores asociados a los casos detectados con el método de Baermann modificado están consulta externa (RP=4,21, IC 95%=1,91-9,28) y heces formadas (RP=3,99, IC 95%=1,94-8,19). Conclusiones. El método de Baermann modificado aumentó la frecuencia de detección de estrongiloidiasis casi cuatro veces. La mayoría de los casos se distribuyeron entre pacientes masculinos adultos. Los casos diagnosticados exclusivamente con el método de Baermann modificado tuvieron diferencias con los casos diagnosticados por examen directo. Es necesario realizar estudios poblacionales.

12.
Lupus ; 32(11): 1328-1334, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37705367

RESUMEN

BACKGROUND: Low disease activity state (LDAS) has been linked to a significant reduction in flares and damage accrual in patients with systemic lupus erythematosus (SLE); however, the effect of LDAS on the risk of vertebral fractures (VFs) in subjects with SLE is unknown, considering that low bone mineral density (BMD) and VF are frequent in SLE. OBJECTIVE: to evaluate whether achieving LDAS ≥50% of the observation time prevents new VF and BMD changes in Mestizo women. METHODS: We carried out a longitudinal, observational, and retrospective study. Mestizo women with SLE were included for a median of an 8-year follow-up. LDAS was described as Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score ≤4, prednisone ≤7.5 mg/day, and stable immunosuppressive therapies. BMD measurements and lateral thoracic and lumbar radiographs for a semiquantitative analysis for VF were assessed at baseline and during the follow-up. Uni- and multivariable interval-censored survival regression models were carried out. RESULTS: We included 110 patients: 35 (31.8%) had new VF. A total of 56 patients (50.1%) achieved LDAS ≥50% of the time during the follow-up and achieved a significantly lesser risk of incident VF (HR = 0.16; 95% CI, 0.06-0.49). After adjusting by age, BMI, menopause, prevalent VF, baseline BMD, cumulative glucocorticoid use, and anti-osteoporotic therapy, LDAS-50 was significantly related to a decrease in the risk of a new VF (HR = 0.39; 95% CI, 0.16-0.98). There was no association between LDAS and BMD measurement changes. When only patients on LDAS but not in remission (n = 43) were evaluated for the risk of incident VF, both uni- and multivariate analyses were significant (HR = 0.12; 95 CI, 0.04-47; p = 0.001, and HR = 0.26; 95% CI, 0.7-0.88; p = 0.03). CONCLUSIONS: LDAS ≥50% of the time was significantly associated with a diminished risk of new VF in Mestizo women with SLE, even in patients not in remission. However, LDAS did not help modify BMD changes over time.


Asunto(s)
Lupus Eritematoso Sistémico , Fracturas de la Columna Vertebral , Femenino , Humanos , Densidad Ósea , Glucocorticoides/uso terapéutico , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Prednisona/uso terapéutico , Estudios Retrospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología
13.
ACS Appl Mater Interfaces ; 15(40): 47025-47036, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37756387

RESUMEN

Electrolyte cations can have significant effects on the kinetics and selectivity of electrocatalytic reactions. We show an atypical mechanism through which electrolyte cations can impact electrocatalyst performance─direct incorporation of the cation into the oxide electrocatalyst lattice. We investigate the transformations of copper electrodes in alkaline electrochemistry through operando X-ray absorption spectroscopy in KOH and Ba(OH)2 electrolytes. In KOH electrolytes, both the near-edge structure and extended fine-structure agree with previous studies; however, the X-ray absorption spectra vary greatly in Ba(OH)2 electrolytes. Through a combination of electronic structure modeling, near-edge simulation, and postreaction characterization, we propose that Ba2+ cations are directly incorporated into the lattice and form an ordered BaCuO2 phase at potentials more oxidizing than 200 mV vs the normal hydrogen electrode (NHE). BaCuO2 formation is followed by further oxidation to a bulk Cu3+-like BaxCuyOz phase at 900 mV vs NHE. Additionally, during reduction in Ba(OH)2 electrolyte, we find both Cu-O bonds and Cu-Ba scattering persist at potentials as low as -400 mV vs NHE. To our knowledge, this is the first evidence for direct oxidative incorporation of an electrolyte cation into the bulk lattice to form a mixed oxide electrode. The oxidative incorporation of electrolyte cations to form mixed oxides could open a new route for the in situ formation of active and selective oxidation electrocatalysts.

14.
Inorg Chem ; 62(36): 14523-14532, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37624729

RESUMEN

Sustainable production of rare earth elements (REEs) is critical for technologies needed for climate change mitigation, including wind turbines and electric vehicles. However, separation technologies currently used in REE production have large environmental footprints, necessitating more sustainable strategies. Aqueous, affinity-based separations are examples of such strategies. To make these technologies feasible, it is imperative to connect aqueous ligand structure to ligand selectivity for individual REEs. As a step toward this goal, we analyzed the extended X-ray absorption fine structure (EXAFS) of four lanthanides (La, Ce, Pr, and Nd) complexed by a common REE chelator, ethylenediaminetetraacetic acid (EDTA) to determine the aqueous-phase structure. Reference structures from density functional theory (DFT) were used to help fit the EXAFS spectra. We found that all four Ln-EDTA coordination complexes formed 9-coordinate structures with 6 coordinating atoms from EDTA (4 carboxyl oxygen atoms and 2 nitrogen atoms) and 3 oxygen atoms from water molecules. All EXAFS fits were of high quality (R-factor < 0.02) and showed decreasing average first-shell coordination distance across the series (2.62-2.57 Å from La-Nd), in agreement with DFT (2.65-2.56 Å from La-Nd). The insights determined herein will be useful in the development of ligands for sustainable rare earth elements (REE) separation technologies.

15.
J Synchrotron Radiat ; 30(Pt 5): 1023-1029, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37594862

RESUMEN

This paper presents software for calculating the optimal mass of samples with complex compositions (e.g. supported metal catalysts) for X-ray absorption spectroscopy (XAS) and scattering measurements. The ability to calculate the sample mass and other relevant parameters needed for an XAS measurement allows experimentalists to be better prepared in terms of detector selection, energy range of scan and overall time needed to complete the measurement, thus increasing efficiency. CatMass builds on existing sample mass calculators allowing users to determine the optimum sample preparation, collection geometry, usable energy range for a scan and approximate edge step of the absorption event. Visualization tools present the absorption calculation results in a format familiar to XAS experimentalists, with the added ability to save calculations and plots for future reference or recalculation. CatMass is a program broadly applicable in catalysis and is helpful for users with complex samples due to composition/stoichiometry or multiple competing elements.

16.
Calcif Tissue Int ; 113(5): 475-480, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37481761

RESUMEN

The Systemic Lupus International Clinics (SLICC)-Frailty Index (FI) is associated with adverse outcomes in systemic lupus erythematosus (SLE). However, to our knowledge, its association with bone mineral density (BMD) and vertebral fractures (VF), has not been investigated using a standardized methods. Our aim was to evaluate the relationship between frailty assessed by SLICC-FI, and BMD and VF in Mestizo women with SLE. Adult women were included in this cross-sectional study. Information concerning the risk factors for VF and BMD in the lumbar spine and total hip was acquired. SLICC-FI was assessed at baseline. A semi-quantitative method was utilized to evaluate the prevalence of VF on lateral thoracolumbar radiographs. Univariate and multivariate regression analyses were performed adjusting for age, body mass index (BMI), SLE duration, cumulative glucocorticoid dose, bisphosphonate use, and BMD measurements. We included 202 women with SLE (mean age [SD] = 43.3 [13.6] years). The mean (SD) SLICC-FI value was 0.14 (0.09). Eleven (5.4%) patients were categorized as robust, 62 (30.7%) as relatively less fit, 84 (41.6%) as least fit, and 45 (22.3%) as frail. Both univariate and multivariate models showed associations between frailty (defined as SLICC-FI > 0.21) and prevalent VF in the entire population (OR 5.76, 95% CI 2.53-13.12; P < 0.001) and in the premenopausal group (OR 4.29, 95% CI; P = 0.047). We also found an association between the SLICC-FI and low BMD. In conclusion, frailty assessed by SLICC-FI might be associated with VF and low BMD in mestizo females with SLE.


Asunto(s)
Enfermedades Óseas Metabólicas , Fragilidad , Lupus Eritematoso Sistémico , Fracturas de la Columna Vertebral , Adulto , Humanos , Femenino , Adolescente , Fragilidad/complicaciones , Estudios Transversales , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/complicaciones , Densidad Ósea , Enfermedades Óseas Metabólicas/complicaciones , Vértebras Lumbares , Factores de Riesgo , Lupus Eritematoso Sistémico/complicaciones
17.
Int J Oral Maxillofac Implants ; 38(3): 545-552, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37279226

RESUMEN

PURPOSE: To compare the frequency of immediate/short-term postoperative bleeding and occurrence of hematomas using tranexamic acid (TXA), bismuth subgallate (BS), or dry gauze (DG) as a local hemostatic agent, and to explore the relation between short-term bleeding and occurrence of intraoral and extraoral hematomas and length of incision, duration of surgery, and alveolar ridge recontouring in patients who were continued on oral anticoagulation therapy. MATERIALS AND METHODS: Eighty surgical procedures performed in 71 patients were assigned to one of four groups (20 each): control group (patients not on oral anticoagulant therapy) and three experimental groups (patients on oral anticoagulation therapy managed with local hemostatic measures): TXAg, BSg, or DGg. Studied variables were length of incision, duration of surgery, and alveolar ridge recontouring. Short-term bleeding episodes and occurrence of intraoral and extraoral hematomas were recorded. RESULTS: A total of 111 implants were placed. No significant differences in mean international normalized ratio, duration of surgery, and length of incision were observed among groups (P > .05). Short-term bleeding and intraoral and extraoral hematomas were observed in 2, 2, and 14 surgical procedures, respectively, and did not differ significantly among groups. Overall relation between variables showed no association between extraoral hematomas and duration of surgery/length of incision (P > .05). Association between extraoral hematomas and alveolar ridge recontouring was statistically significant (OR = 26.72). Association with short-term bleeding and intraoral hematomas was not studied due to the small number of events. CONCLUSION: Implant placement in warfarin anticoagulated patients without withdrawing oral anticoagulation therapy is a safe and predictable procedure, and different local hemostatic agents (TXA, BS, and DG) are effective in managing postoperative bleeding. Development of hematomas may be higher in patients undergoing alveolar ridge recontouring. Further studies are necessary to confirm these results. Int J Oral Maxillofac Implants 2023;38:545-552. doi: 10.11607/jomi.9846.


Asunto(s)
Implantes Dentales , Hemostáticos , Ácido Tranexámico , Humanos , Warfarina/efectos adversos , Hemostáticos/uso terapéutico , Extracción Dental/métodos , Anticoagulantes/efectos adversos , Hemorragia Posoperatoria/inducido químicamente , Hemorragia Posoperatoria/tratamiento farmacológico , Ácido Tranexámico/uso terapéutico
18.
Rheumatol Int ; 43(9): 1611-1619, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37349634

RESUMEN

The study aimed to analyze the influence of the COVID-19 pandemic on mortality rates in patients with systemic autoimmune rheumatic diseases (SARD) in Mexico. We selected SARD-related deaths using National Open Data and Information from the Ministry of Health, Mexico, and ICD-10 codes. We assessed the observed compared to the predicted mortality values for 2020 and 2021, employing trends from 2010 to 2019 with joinpoint and prediction modelling analyses. Among 12,742 deaths due to SARD between 2010 and 2021, the age-standardized mortality rate (ASMR) increased significantly between 2010 and 2019 (pre-pandemic) (annual percentage change [APC] 1.1%; 95% CI 0.2-2.1), followed by a non-significant decrease during the pandemic period (APC 13.9%; 95% CI 13.9-5.3). In addition, the observed ASMR of 1.19 for 2020 for SARD and of 1.14 for 2021 were lower than the predicted values of 1.25 (95% CI 1.22-1.28) for 2020 and 1.25 (95% CI 1.20-1.30) for 2021. Similar findings were identified for specific SARD, mainly systemic lupus erythematosus (SLE), or by sex or age group. Interestingly, the observed mortality rates for SLE in the Southern region of 1.00 in 2020 and 1.01 in 2021 were both significantly greater than the predicted values of 0.71 (95% CI 0.65-0.77) in 2020 and 0.71 (95% CI 0.63-0.79). In Mexico, the observed SARD mortality rates were not higher than the expected values during the pandemic, except for SLE in the Southern region. No differences by sex or age group were identified.


Asunto(s)
Enfermedades Autoinmunes , COVID-19 , Lupus Eritematoso Sistémico , Enfermedades Reumáticas , Humanos , Pandemias , México/epidemiología
19.
J Phys Chem Lett ; 14(19): 4591-4599, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37166100

RESUMEN

Quick-scanning X-ray absorption fine structure (QXAFS) measurements were used to characterize the exchanges of ethylene and CO ligands in a zeolite HY-supported single-site Rh complex at a sampling rate of 1.0 Hz. The two ligands were reversibly exchanged on the rhodium, with quantitative results determined for the C2H4-for-CO exchange that are consistent with a first-order process. The apparent rate constant for the exchange decreased with increasing temperature. Fourier-transform infrared spectra characterizing the C2H4 sorbed in the zeolite showed that the amount decreased with increasing temperature, consistent with the decrease in the exchange rate with increasing temperature. The results, illustrating the dynamics of ligand exchanges on a single-site supported metal catalyst, demonstrate the broad emerging applicability of the QXAFS technique for characterizing the dynamics of reactive intermediates on catalysts.

20.
Horm Metab Res ; 55(7): 487-492, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37178683

RESUMEN

The aims of this study were in systemic lupus erythematosus (SLE) patients: 1) to compare the metabolomic profile of insulin resistance (IR) with controls and 2) to correlate the metabolomic profile with other IR surrogates and SLE disease variables and vitamin levels. In this cross-sectional study, serum samples were collected from women with SLE (n=64) and gender- and age-matched controls (n=71), which were not diabetic. Serum metabolomic profiling was performed using UPLC-MS-MS (Quantse score). HOMA and QUICKI were carried out. Serum 25(OH)D concentrations were measured by chemiluminescent immunoassay. In women with SLE, the metabolomic Quantose score significantly correlated with HOMA-IR, HOMA2-IR, and QUICKI. Although concentrations of IR metabolites were not different between SLE patients and controls, fasting plasma insulin levels were higher and insulin sensitivity lower in SLE women. Interestingly, the Quantose IR score was significantly correlated with complement C3 levels (r=0.7; p=0.001). 25 (OH)D did not correlate with any metabolite or the Quantose IR index. Quantose IR may be a useful tool for IR assessment. There was a possible correlation between the metabolomic profile and complement C3 levels. The implementation of this metabolic strategy may help develop biochemical insight into metabolic disorders in SLE.


Asunto(s)
Resistencia a la Insulina , Lupus Eritematoso Sistémico , Humanos , Femenino , Complemento C3 , Estudios Transversales , Cromatografía Liquida , Espectrometría de Masas en Tándem , Insulina
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