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1.
ACS Appl Mater Interfaces ; 16(17): 21877-21884, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648335

RESUMO

The hydrogen evolution reaction (HER) is a crucial electrochemical process for the proposed hydrogen economy since it has the potential to provide pure hydrogen for fuel cells. Nowadays, hydrogen electroproduction is considerably expensive, so promoting the development of new non-noble catalysts for the cathode of alkaline electrolyzers appears as a suitable way to reduce the costs of this technology. In this sense, a series of tungsten-based carbide materials have been synthesized by the urea-glass route as candidates to improve the HER in alkaline media. Moreover, two different pyridinium-based ionic liquids were employed to modify the surface of the carbide grains and control the amount and nature of their surface species. The main results indicate that the catalyst surface composition is modified in the hybrid materials, which are then distinguished by the appearance of tungsten suboxide structures. This implies the action of ionic liquids as reducing agents. Consequently, differential electrochemical mass spectrometry (DEMS) is used to precisely determine the onset potentials and rate-determining steps (RDS) for the HER in alkaline media. Remarkably, the modified surfaces show high catalytic performance (overpotentials between 45 and 60 mV) and RDS changes from Heyrovsky-Volmer to Heyrovsky as the surface oxide structures get reduced. H2O molecule reduction is then faster at tungsten suboxide, which allows the formation of the adsorbed hydrogen at the surface, boosting the catalytic activity and the kinetics of the alkaline HER.

2.
J Chem Phys ; 160(11)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38501474

RESUMO

SiCH and its cation have consistently emerged as predicted species in models of silicon chemistry within the interstellar medium, although they remain unobserved in space. Hindered by their intrinsic instability, no spectroscopic insights have been gleaned concerning the SiCH+ cation. In this study, we present experimental measurements on the SiCH+ cation through single-photon ionization spectroscopy of the SiCH radical within the 8.0-11.0 eV range. Gas-phase SiCH radicals were generated through chemical reactions involving CHx (x = 0-3) and SiHy (y = 0-3) within a microwave discharge flow-tube reactor. Employing a double imaging photoelectron/photoion coincidence spectrometer on the DESIRS beamline at the SOLEIL synchrotron, we recorded mass-selected ion yield and photoelectron spectra. From the analysis of the photoelectron spectrum supported by ab initio calculations and Franck-Condon simulations, the adiabatic ionization energies for the transitions from the X2Π ground electronic state of SiCH toward the X+3Σ- and A+3Π electronic states of SiCH+ have been derived [8.935(6) and 10.664(6) eV, respectively, without spin-orbit correction]. The contribution from the less stable isomer HSiC has been explored in our analysis and ruled out in our experiments.

3.
Public Health ; 229: 160-166, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447299

RESUMO

OBJECTIVES: Previous studies suggest that there is discordance between actual weight status and body-weight perception. This fact has implications when it comes to designing public health interventions. The aim of this study was to estimate the prevalence of the different categories of weight status and body-weight perception and to analyse their concordance in a representative Spanish population sample. STUDY DESIGN: Cross-sectional study. METHODS: Data were sourced from the 2018 Galician Risk Behaviour Data System, with the target population being all persons aged 16 years and above. We collected data on self-perceived body weight and assessed weight status on the basis of body mass index (BMI). BMI was estimated using self-reported measures of weight and height. To estimate concordance, Cohen's kappa coefficient, both unweighted and weighted with Cicchetti weights, was calculated. RESULTS: Data were obtained for 7853 individuals aged 16 years and above, whereas the overall unweighted concordance was 0.393 (95%CI: 0.377-0.409), with an agreement percentage of 61.6%, weighted concordance was 0.503 (0.490-0.517), with an agreement percentage of 86.6%. The highest concordance between self-perceived body weight and weight status was observed in women. By age group, the highest concordance was observed in the youngest group (16-24 years) for the BMI categories of underweight and overweight, and in the 45-64 age group for the category of obesity. CONCLUSIONS: The results highlight the existence of differences between self-perceived body weight and weight status, according to sex and age.


Assuntos
Obesidade , Sobrepeso , Humanos , Feminino , Pessoa de Meia-Idade , Peso Corporal , Estudos Transversais , Obesidade/epidemiologia , Índice de Massa Corporal , Sobrepeso/epidemiologia
4.
Phys Chem Chem Phys ; 26(12): 9197-9206, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38376884

RESUMO

The electron induced dissociation of condensed benzene (C6H6) in thin films deposited on a Pt substrate is investigated by electron stimulated desorption (ESD) of anions and cations. The desorbed yields are recorded as a function of incident electron energy in the range of 10 to 950 eV for a fixed film thickness of 2 monolayers (ML) and for a fixed energy of 950 eV, as well as a function of film thickness from 0.5 to 8 monolayers (ML) for anions, and from 0.5 to 12ML for cations. Both energy and thickness dependencies are discussed in terms of the three main mechanisms yielding positively and/or negatively charged fragments: dissociative electron attachment (DEA), dipolar dissociation (DD) and dissociative ionization (DI) processes. At the probed energies, DD is the major mechanism, while DEA is predominantly induced by secondary electrons from the Pt substrate. Desorption of the parent positive ion is strongly suppressed. Similar qualitative behaviours are observed for the energy dependence of both anion and cation ESD yields, while some discrepancies exist in the thickness dependence, including a very significant systematic magnitude difference found between such ions formation. An estimation of the effective DD cross-section including the desorption probability is obtained. Feasible mechanisms behind the observed energy and thickness dependences for anion and cation yields are proposed. These results highlight the need for further investigations to better understand the underlying processes of electron induced dissociation in condensed matter.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38368528

RESUMO

BACKGROUND: The removal of third molars (3Ms) is the most frequent surgical procedure in the field of Oral Surgery. As a result, the Spanish Society of Oral Surgery (SECIB) aims to create a Clinical Practice Guideline (CPG) that offers evidence-based recommendations for optimal clinical practice. Specifically, the CPG will focus on providing guidance regarding the indications and criteria for clinical and radiological diagnosis of patients with 3Ms. MATERIAL AND METHODS: This CPG was developed by the SECIB, following the methodological guidelines described in the methodological manual for the "Development of Clinical Practice Guidelines in the National Health System". Several PICO questions related to the diagnosis and indications for the extraction of 3Ms were formulated. The leading experts carried out the evaluation of the evidence and the formulation of specific recommendations. RESULTS: A total of 17 PICO questions were evaluated, addressing the indications, prognosis, diagnosis, and cost-benefit relationship of 3M extraction. CONCLUSIONS: The present Clinical Practice Guideline provides evidence-based recommendations on the diagnosis and indications for 3M extraction. These evidence-based recommendations can assist healthcare professionals and the general population in making informed decisions regarding the management of 3Ms.

6.
Actas Dermosifiliogr ; 115(3): T293-T297, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38242433

RESUMO

Although subungual melanoma is uncommon, it is associated with worse outcomes than melanomas in other locations and accounts for 1% to 23% of all melanomas, depending on the population. The aim of this study was to describe the clinical and histopathologic features of subungual melanoma in a Mexican population. We identified 303 patients with melanoma, and of these, 19% (57 patients with a median age of 71 years) had subungual melanoma. The main sites affected were the lower limbs (52.6%) and the toe (75.4%). The most common histologic subtype was acral lentiginous melanoma (50.9%). Median Breslow thickness was 3 mm, and stage IA tumors were the most common (in 28.1% of patients). Recurrence and metastasis occurred in 19.3% and 8.8% of patients, respectively. The clinical and histopathologic features identified are similar to those described in the literature. Early diagnosis and treatment are crucial for improving prognosis.


Assuntos
Melanoma , Doenças da Unha , Neoplasias Cutâneas , Humanos , Idoso , Melanoma/patologia , Estudos de Coortes , Neoplasias Cutâneas/patologia , Doenças da Unha/diagnóstico , Prognóstico
8.
Actas Dermosifiliogr ; 115(3): 293-297, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37871891

RESUMO

Although subungual melanoma is uncommon, it is associated with worse outcomes than melanomas in other locations and accounts for 1% to 23% of all melanomas, depending on the population. The aim of this study was to describe the clinical and histopathologic features of subungual melanoma in a Mexican population. We identified 303 patients with melanoma, and of these, 19% (57 patients with a median age of 71 years) had subungual melanoma. The main sites affected were the lower limbs (52.6%) and the toe (75.4%). The most common histologic subtype was acral lentiginous melanoma (50.9%). Median Breslow thickness was 3 mm, and stage IA tumors were the most common (in 28.1% of patients). Recurrence and metastasis occurred in 19.3% and 8.8% of patients, respectively. The clinical and histopathologic features identified are similar to those described in the literature. Early diagnosis and treatment are crucial for improving prognosis.


Assuntos
Melanoma , Doenças da Unha , Neoplasias Cutâneas , Humanos , Idoso , Melanoma/patologia , Estudos de Coortes , Neoplasias Cutâneas/patologia , Doenças da Unha/diagnóstico , Prognóstico
10.
Glob Chang Biol ; 30(1): e16997, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37937346

RESUMO

Mediterranean spring ecosystems are unique habitats at the interface between surface water and groundwater. These ecosystems support a remarkable array of biodiversity and provide important ecological functions and ecosystem services. Spring ecosystems are influenced by abiotic, biotic, and anthropogenic factors such as the lithology of their draining aquifers, their climate, and the land use of their recharge area, all of which affect the water chemistry of the aquifer and the spring discharges. One of the most relevant characteristics of spring ecosystems is the temporal stability of environmental conditions, including physicochemical features of the spring water, across seasons and years. This stability allows a wide range of species to benefit from these ecosystems (particularly during dry periods), fostering an unusually high number of endemic species. However, global change poses important threats to these freshwater ecosystems. Changes in temperature, evapotranspiration, and precipitation patterns can alter the water balance and chemistry of spring water. Eutrophication due to agricultural practices and emergent pollutants, such as pharmaceuticals, personal care products, and pesticides, is also a growing concern for the preservation of spring biodiversity. Here, we provide a synthesis of the main characteristics and functioning of Mediterranean spring ecosystems. We then describe their ecological value and biodiversity patterns and highlight the main risks these ecosystems face. Moreover, we identify existing knowledge gaps to guide future research in order to fully uncover the hidden biodiversity within these habitats and understand the main drivers that govern them. Finally, we provide a brief summary of recommended actions that should be taken to effectively manage and preserve Mediterranean spring ecosystems for future generations. Even though studies on Mediterranean spring ecosystems are still scarce, our review shows there are sufficient data to conclude that their future viability as functional ecosystems is under severe threat.


Assuntos
Ecossistema , Nascentes Naturais , Refúgio de Vida Selvagem , Biodiversidade , Água
13.
ESMO Open ; 8(6): 102038, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37922690

RESUMO

BACKGROUND: BRAF inhibitors are approved in BRAFV600-mutated metastatic melanoma, non-small-cell lung cancer (NSCLC), Erdheim-Chester disease (ECD), and thyroid cancer. We report here the efficacy, safety, and long-term results of single-agent vemurafenib given in the AcSé vemurafenib basket study to patients with various BRAF-mutated advanced tumours other than BRAFV600-mutated melanoma and NSCLC. PATIENTS AND METHODS: Patients with advanced tumours other than BRAFV600E melanoma and progressing after standard treatment were eligible for inclusion in nine cohorts (including a miscellaneous cohort) and received oral vemurafenib 960 mg two times daily. The primary endpoint was the objective response rate (ORR) estimated with a Bayesian design. The secondary outcomes were disease control rate, duration of response, progression-free survival (PFS), overall survival (OS), and vemurafenib safety. RESULTS: A total of 98 advanced patients with various solid or haematological cancers, 88 with BRAFV600 mutations and 10 with BRAFnonV600 mutations, were included. The median follow-up duration was 47.7 months. The Bayesian estimate of ORR was 89.7% in hairy cell leukaemias (HCLs), 33.3% in the glioblastomas cohort, 18.2% in cholangiocarcinomas, 80.0% in ECD, 50.0% in ovarian cancers, 50.0% in xanthoastrocytomas, 66.7% in gangliogliomas, and 60.0% in sarcomas. The median PFS of the whole series was 8.8 months. The 12-, 24-, and 36-month PFS rates were 42.2%, 23.8%, and 17.9%, respectively. Overall, 54 patients died with a median OS of 25.9 months, with a projected 4-year OS of 40%. Adverse events were similar to those previously reported with vemurafenib. CONCLUSION: Responses and prolonged PFS were observed in many tumours with BRAF mutations, including HCL, ECD, ovarian carcinoma, gliomas, ganglioglioma, and sarcomas. Although not all cancer types responded, vemurafenib is an agnostic oncogene therapy of cancers.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Melanoma , Sarcoma , Humanos , Vemurafenib/farmacologia , Vemurafenib/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Teorema de Bayes , Resultado do Tratamento , Sulfonamidas/efeitos adversos , Intervalo Livre de Doença , Mutação
14.
bioRxiv ; 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37790389

RESUMO

Dendritic spines are small protrusions on dendrites in neurons and serve as sites of postsynaptic activity. Some of these spines contain smooth endoplasmic reticulum (SER), and sometimes an even further specialized SER known as the spine apparatus (SA). In this work, we developed a stochastic spatial model to investigate the role of the SER and the SA in modulating Ca 2+ dynamics. Using this model, we investigated how ryanodine receptor (RyR) localization, spine membrane geometry, and SER geometry can impact Ca 2+ transients in the spine and in the dendrite. Our simulations found that RyR opening is dependent on where it is localized in the SER and on the SER geometry. In order to maximize Ca 2+ in the dendrites (for activating clusters of spines and spine-spine communication), a laminar SA was favorable with RyRs localized in the neck region, closer to the dendrite. We also found that the presence of the SER without the laminar structure, coupled with RyR localization at the head, leads to higher Ca 2+ presence in the spine. These predictions serve as design principles for understanding how spines with an ER can regulate Ca 2+ dynamics differently from spines without ER through a combination of geometry and receptor localization. Highlights: 1RyR opening in dendritic spine ER is location dependent and spine geometry dependent. Ca 2+ buffers and SERCA can buffer against runaway potentiation of spines even when CICR is activated. RyRs located towards the ER neck allow for more Ca 2+ to reach the dendrites. RyRs located towards the spine head are favorable for increased Ca 2+ in spines.

15.
Dalton Trans ; 52(40): 14453-14464, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37772605

RESUMO

In this work, CuOx (x = 1 and 2) nanostructures have been synthesized by electrochemical anodization in ethylene glycol based electrolytes using oxalic acid or NaF (with or without NaOH) as complexing agents. The influence of hydrodynamic conditions and time during anodization of copper have also been evaluated. A comprehensive morphological, structural, electrochemical and photoelectrochemical characterization of the nanostructures has been performed. The results revealed the convenient use of oxalic acid and 250 rpm for 5 minutes during electrochemical anodization to obtain homogeneous CuOx nanostructures formed by spheres with Cu2O as a predominant phase. Using this nanostructure as a photocathode for N2O photoelectron-reduction, almost 100% of N2O removal was achieved after 1 h, showing the improvement of the photoelectrochemical approach vs. the photo or the electro performance.

16.
Rev Clin Esp (Barc) ; 223(9): 523-531, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37716428

RESUMO

OBJECTIVE: To describe patients hospitalized in internal medicine in terms of malnutrition and sarcopenia, depending on the presence or absence of type 2 diabetes mellitus (DM2), as well as to evaluate short- and long-term mortality related to both. METHODS: Cross-sectional, single-center study, which included consecutive patients admitted to internal medicine in May and October 2021. Malnutrition was determined using the Mini Nutritional Assessment-Short Form (MNA-SF) and sarcopenia using SARC-F and handgrip strength. Patients hospitalized for more than 48 h are excluded. RESULTS: 511 patients were analyzed, 49.1% male, mean age 75.2 +/- 15 years, 210 (41.1%) DM2. 6 groups (2 × 3 design) are generated based on the presence of DM2 and the nutritional status according to the result of the MNA-SF: 12-14 points, without risk; MNA-SF 8-12 points, high risk; MNA-SF 0-7 points, malnourished. Malnourished patients with DM2 had significantly higher sarcopenia, comorbidity, inflammation, and pressure ulcers. The main determinants of in-hospital mortality were sarcopenia (OR 1.27, 95%CI 1.06-1.54, p = 0.01), comorbidity (OR 1.27, 95%CI 1,08-1,49, p = 0.003) and inflammation (OR 1.01, 95%CI 1.00-1.02, p = 0.02). The 120-day prognosis was worse among malnourished patients (p = 0.042). CONCLUSION: Patients admitted with DM2 have a similar degree of malnutrition than the rest, but with greater sarcopenia. This sarcopenia, together with inflammation and comorbidity determine a worse prognosis. The active and early identification of malnutrition and sarcopenia and their subsequent approach could improve the prognosis of patients.


Assuntos
Diabetes Mellitus Tipo 2 , Desnutrição , Sarcopenia , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Sarcopenia/diagnóstico , Força da Mão , Estudos Transversais , Desnutrição/complicações , Prognóstico , Inflamação , Medicina Interna , Avaliação Geriátrica
17.
Phys Chem Chem Phys ; 25(35): 23568-23578, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37656136

RESUMO

We report the first experimental observation of single-photon ionization transitions of the SiC radical between 8.0 and 11.0 eV performed on the DESIRS beamline at the SOLEIL synchrotron facility. The SiC radical, very difficult to synthesize in the gas phase, was produced through chemical reactions between CHx (x = 0-3) and SiHy (y = 0-3) in a continuous microwave discharge flow tube, the CHx and SiHy species being formed by successive hydrogen-atom abstractions induced by fluorine atoms on methane and silane, respectively. Mass-selected ion yield and photoelectron spectra were recorded as a function of photon energy using a double imaging photoelectron/photoion coincidence spectrometer. The photoelectron spectrum enables the first direct experimental determinations of the X+ 4Σ- ← X 3Π and 1+ 2Π â† X 3Π adiabatic ionization energies of SiC (8.978(10) eV and 10.216(24) eV, respectively). Calculated spectra based on Franck-Condon factors are compared with the experimental spectra. These spectra were obtained by solving the rovibrational Hamiltonian, using the potential energy curves calculated at the multireference single and double configuration interaction level with Davidson correction (MRCI + Q) and the aug-cc-pV5Z basis set. MRCI + Q calculations including the core and core-valence electron correlation were performed using the aug-cc-pCV6Z basis set to predict the spectroscopic properties of the six lowest electronic states of SiC+. Complete basis set extrapolations and relativistic energy corrections were also included in the determination of the energy differences characterizing the photoionization process. Using our experimental and theoretical results, we derived semi-experimental values for the five lowest ionization energies of SiC.

18.
Microsc Microanal ; 29(Supplement_1): 876-877, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37613712
19.
J Hosp Infect ; 142: 26-31, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37499762

RESUMO

BACKGROUND: Severe COVID-19 elicits a hyperimmune response frequently amenable to steroids, which in turn increase the risk for opportunistic infections. COVID-19 associated pulmonary aspergillosis (CAPA) is a complication known to be associated with immunomodulatory treatment. The role of cumulative steroid dose in the development of CAPA is unclear. This study evaluates the relationship between cumulative steroid dose in hospitalized individuals with COVID-19 pneumonia and the risk for CAPA. METHODS: This retrospective cohort study includes 135 hospitalized patients with PCR-confirmed COVID-19 pneumonia at a tertiary centre in north Mexico. Patients who developed CAPA were matched by age and gender to two controls with COVID-19 pneumonia who did not develop CAPA defined and classified as possible, probable, or proven according to 2020 ECMM/ISHAM criteria. Cumulative steroid dose in dexamethasone equivalents was obtained from admission until death, discharge, or diagnosis of CAPA (whichever occurred first). The risk of CAPA by the continuous cumulative steroid dose was assessed using a logistic regression model. RESULTS: Forty-five patients were diagnosed with CAPA and matched to 90 controls. Mean age was 61 ± 14 years, and 72% were male. Mean cumulative steroid dose was 66 ± 75 mg in patients without CAPA vs 195 ± 226 mg in patients with CAPA (P<0.001). The risk for CAPA increased with higher cumulative dose of steroids (OR 1.0075, 95% CI: 1.0033-1.0116). CONCLUSIONS: Patients who developed CAPA had a history of higher cumulative steroid dose during hospitalization. The risk for CAPA increases ∼8% for every 10 mg of dexamethasone used.


Assuntos
COVID-19 , Aspergilose Pulmonar , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Estudos Retrospectivos , Esteroides/efeitos adversos , Dexametasona/efeitos adversos
20.
Phys Chem Chem Phys ; 25(30): 20510-20518, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37470102

RESUMO

In this study, a complete and self-consistent cross section dataset for electron transport simulations through gaseous benzene in the energy range 0.1-1000 eV has been critically compiled. Its reliability has been evaluated through a joint experimental and computational procedure. To accomplish this, the compiled dataset has been used as input for event-by-event Monte Carlo simulations of the magnetically confined electron transport through gaseous benzene, and the simulated transmitted intensity has been compared with the experimental one for different incident energies and benzene gas pressures.

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