Sol–gel synthesis and characterization of Co-doped LSGM perovskites

One of the major requirements for the development and commercialization of low-cost SOFCs is the reduction in the operating temperature. One of the methods to reach this aim is the use of solid electrolytes which exhibit superior ionic conductivity at intermediate temperatures (IT, T < 800 °C). Among these ionic conductors, doped LaGaO3 materials show high oxide ionic conductivity in the 600–800 °C range. These perovskites are usually prepared by time- and energy-consuming solid state reaction. In this paper, La0.8Sr0.2Ga0.8Mg0.2O2.8 (LSGM) and La0.8Sr0.20Ga0.8Mg0.2−xCoxO3−δ (LSGMC) powders containing different amounts of Co (x = 0.05, 0.085 and 0.10) were prepared from precursors synthesised by citrate sol–gel method. The precursors were calcined at 1000 °C (10 h) and dense high-purity pellets were obtained by pressing (300 MPa) and sintering in air at 1475 °C (5, 10 and 20 h). Sintered pellets of LSGM and LSGMC contained very small amounts (<1%) of SrLaGa3O7 and SrLaGaO4, respectively, as detected by X-ray diffraction (XRD) and by the combined use of scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The data clearly showed the feasibility of sol–gel methods to produce Co-doped LSGM perovskite type oxides

Sol–gel synthesis, X-ray photoelectron spectroscopy and electrical conductivity of Co-doped (La, Sr)(Ga, Mg)O3−δ perovskites

La0.8Sr0.2Ga0.8Mg0.2−xCoxO3−δ (LSGMC) powders containing different amounts of Co (x = 0.05 and 0.085) were prepared by a citrate sol–gel method. The powders were used to prepare highly phase-pure LSGMC sintered pellets with controlled composition and fractional densities larger than 95%. For the first time, LSGMC materials were subjected to X-ray photoelectron spectroscopy (XPS) characterization. XPS data confirmed the presence of the dopants in the material and allowed to identify two different chemical states for Sr2+ and oxygen, both related to the oxygen-deficient perovskite structure of LSGMC. The conductivity of LSGMC sintered pellets containing different amounts of Co ions in the B sites of the perovskite lattice was assessed by electrochemical impedance spectroscopy (EIS) in the 250–750 °C temperature range. Conductivity values and apparent activation energies were in good agreement with previously published data referring to materials with same composition, but prepared by solid-state route. Therefore, the physicochemical and electrochemical characterization clearly demonstrated the ability of sol–gel methods to produce high-purity Co-doped LSGM perovskites, which represent promising solid electrolytes for intermediate-temperature SOFCs

Shared Molecular Mechanisms among Alzheimer’s Disease, Neurovascular Unit Dysfunction and Vascular Risk Factors: A Narrative Review

Alzheimer’s disease (AD) is the most common type of dementia, affecting 24 million individuals. Clinical and epidemiological studies have found several links between vascular risk factors (VRF), neurovascular unit dysfunction (NVUd), blood-brain barrier breakdown (BBBb) and AD onset and progression in adulthood, suggesting a pathogenetic continuum between AD and vascular dementia. Shared pathways between AD, VRF, and NVUd/BBB have also been found at the molecular level, underlining the strength of this association. The present paper reviewed the literature describing commonly shared molecular pathways between adult-onset AD, VRF, and NVUd/BBBb. Current evidence suggests that VRF and NVUd/BBBb are involved in AD neurovascular and neurodegenerative pathology and share several molecular pathways. This is strongly supportive of the hypothesis that the presence of VRF can at least facilitate AD onset and progression through several mechanisms, including NVUd/BBBb. Moreover, vascular disease and several comorbidities may have a cumulative effect on VRF and worsen the clinical manifestations of AD. Early detection and correction of VRF and vascular disease by improving NVUd/BBBd could be a potential target to reduce the overall incidence and delay cognitive impairment in AD

Multidisciplinary approach to the forensic identification of a late discovery victim of a motorcycle accident

This paper presents a case of a late discovery of a motorcycle accident victim. The fact that the remains were almost skeletonized required the input of several disciplines in order to identify the victim. Therefore, anthropology, odontology, facial reconstruction, and genetics were employed. It was found that the victim was male, between the ages of 35 to 55 with a number of healed fractures. In addition, perimortem trauma with a pattern that was consistent with a motorcycle accident was found in the head and upper body regions. Dental findings included a tooth out of alignment with the rest of the dental arcade, as well as a heavily decayed tooth that was replaced by a dental bridge. Both of these findings were supported by ante mortem photographs of the victim. A two-dimensional facial reconstruction was carried out and produced a very good likeness of the deceased. The above findings were confirmed by DNA analysis that matched a bone sample to those of the family of the deceased. This case illustrates the benefits of combining several different methods to make an initial assessment of a case and narrow the list of potential candidates. This can help speed up the process of identification and save resources for law enforcement agencies

Uropathogenic Escherichia coli (UPEC) strains may carry virulence properties of diarrhoeagenic E-coli

To analyze whether Escherichia coli strains that cause urinary tract infections (UPEC) share virulence characteristics with the diarrheagenic E. coli (DEC) pathotypes and to recognize their genetic diversity, 225 UPEC strains were examined for the presence of various properties of DEC and UPEC (type of interaction with HeLa cells, serogroups and presence of 30 virulence genes). No correlation between adherence patterns and serogroups was observed. Forty-five serogroups were found, but 64% of the strains belonged to one of the 12 serogroups (O1, O2, O4, O6, O7, O14, O15, O18, O21, O25, O75, and O175) and carried UPEC virulence genes (pap, hly, aer, sfa, cnf). the DEC genes found were: aap, aatA, aggC, agg3C, aggR, astA, eae, ehly, iha, irp2, lpfA(O113), pet, pic, pilS, and shf. Sixteen strains presented aggregative adherence and/or the aatA sequence, which are characteristics of enteroaggregative E. coli (EAEC), one of the DEC pathotypes. in summary, certain UPEC strains may carry DEC virulence properties, mostly associated to the EAEC pathotype. This finding raises the possibility that at least some faecal EAEC strains might represent potential uropathogens. Alternatively, certain UPEC strains may have acquired EAEC properties, becoming a potential cause of diarrhoea.Universidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilUniv Santiago de Compostela, Fac Vet, Dept Microbiol & Parasitol, Lab Referencia E Coli, Lugo, SpainUniversidade Federal de São Paulo, Lab Cent Hosp São Paulo, São Paulo, BrazilInst Butantan, Bacteriol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Lab Cent Hosp São Paulo, São Paulo, BrazilWeb of Scienc

Disfagia orofaríngea neurogênica: análise de protocolos de videofluoroscopia brasileiros e norte-americanos

Resumo: Este artigo tem por objetivo analisar e comparar o uso de protocolos brasileiros e norte-americanos para videofluoroscopia da deglutição em pacientes com histórico de acidente vascular encefálico. Trata-se de uma revisão bibliográfica de artigos brasileiros e norte-americanos. Foram selecionados artigos com descrição de procedimentos para videofluoroscopia da deglutição em sujeitos que sofreram acidente vascular encefálico, publicados entre 2003 e 2013. Os procedimentos descritos para realização de videofluoroscopias foram analisados de forma quantitativa e qualitativa. Consideraram-se as variáveis: posicionamento para o exame, consistências e quantidades de oferta de bolo, tipos de utensílios e utilização de protocolos Foram encontrados 16 artigos que atenderam aos critérios supracitados, sendo nove (56,25%) norte-americanos e sete (43,75%) brasileiros. Observou-se que quatro dos estudos nacionais (57,14%) não relatam as quantidades oferecidas, enquanto todos os artigos norte-americanos detalharam as quantidades, que variaram entre 2 e 15 mL; os tipos de alimento e suas consistências foram detalhadas em todos os estudos nacionais e norte-americanos, porém os nacionais o fizeram de forma genérica, sem identificação dos alimentos. Quanto à posição do paciente durante o exame, 57,14% dos artigos nacionais não relataram e todos os artigos norte-americanos o fizeram. Os utensílios para oferta do bolo são citados em 55,55% dos artigos norte-americanos e em apenas 14,28 % dos nacionais. Quanto à utilização de protocolos para avaliação 33% dos estudos norte-americanos não os citam, comparados aos 71,42% dos nacionais. Observou-se a necessidade de padronização dos procedimentos e terminologias utilizadas na videofluoroscopia da deglutição, de modo a facilitar a intercompreensão e reprodutibilidade dos estudos

CHA2DS2-VASc score predicts atrial fibrillation recurrence after cardioversion: systematic review and individual patient pooled meta-analysis

BackgroundDespite progresses in the treatment of the thromboembolic risk related to atrial fibrillation (AF), the management of recurrences remains a challenge.HypothesisTo assess if congestive heart failure or left ventricular systolic dysfunction (CHA2DS2‐VASc) score is predictive of early arrhythmia recurrence after AF cardioversion.MethodsSystematic review and individual patient pooled meta‐analysis following Preferred Reporting Items for Systematic reviews and Meta‐Analyses guidelines. Inclusion criteria: observational trials in patients with AF undergoing cardioversion, available data on recurrence of AF and available data on CHA2DS2‐VASc score. Clinical studies of interest were retrieved by PubMed, Cochrane Library, and Biomed Central. Seven authors were contacted for joining the patient level meta‐analysis, and three shared data regarding anthropometric measurements, risk factors, major comorbidities, and CHA2DS2‐VASc score. The primary outcome was the recurrence of AF after cardioversion in patients free from antiarrhythmic prophylaxis. Univariate and multivariate logistic regression was performed.ResultsOverall, we collect data of 2889 patients: 61% were male, 50% with hypertension, 12% with diabetes, and 23% with history of ischemic heart disease. The median CHA2DS2‐VASc score was 2.. At the multivariate analysis, chronic kidney disease (odds ratio [OR] 1.94; 95% confidence interval [CI] 1.12‐3.27; P = 0.01), peripheral artery disease (OR 1.65; 95% CI 1.23‐2.19; P P  2 (OR 1.37; 95% CI 1.1‐1.68; P = 0.002) were independent predictors of early recurrence of AF.ConclusionsCHA2DS2‐VASc score predicts early recurrence of AF in the first 30 days after electrical or pharmacological cardioversion.N