RESUMO
We present a new method to synthesize bulk indium nitride by means of a simple solid-state chemical reaction carried out under hydrostatic high-pressure/high-temperature conditions in a multi-anvil apparatus, not involving gases or solvents during the process. The reaction occurs between the binary oxide In2O3 and the highly reactive Li3N as the nitrogen source, in the powder form. The formation of the hexagonal phase of InN, occurring at 350 °C and P ≥ 3 GPa, was successfully confirmed by powder X-ray diffraction, with the presence of Li2O as a unique byproduct. A simple washing process in weak acidic solution followed by centrifugation allowed us to obtain pure InN polycrystalline powders as a precipitate. With an analogous procedure, it was possible to obtain pure bulk GaN, from Ga2O3 and Li3N at T ≥ 600 °C and P ≥ 2.5 GPa. These results point out, particularly for InN, a clean, and innovative way to produce significant quantities of one of the most promising nitrides in the field of electronics and energy technologies.
RESUMO
PURPOSE: Delirium risk assessment in the acute-care setting generally does not account for frailty. The objective of this retrospective study was to identify factors associated with delirium, considering the interdependency of clinical variables with frailty syndrome in complex older patients. METHODS: The clinical records of 587 participants (248 M, median age 84) were reviewed, collecting clinical, anamnestic and pharmacological data. Frailty syndrome was assessed with the Clinical Frailty Scale (CFS). Delirium was the main study endpoint. The correlations of the considered anamnestic and clinical variables with delirium and its subtypes were investigated selecting only those variables not showing a high overlap with frailty. Correlations associated with a 25% excess of frequency of delirium in comparison with the average of the population were considered as statistically significant. RESULTS: Delirium was detected in 117 (20%) participants. The presence of one among age > 85 years old, CFS > 4 and invasive devices explained 95% of delirium cases. The main factors maximizing delirium incidence at the individual level were dementia, other psychiatric illness, chronic antipsychotic treatment, and invasive devices. The coexistence of three of these parameters was associated with a peak frequency of delirium, ranging from 57 to 61%, mostly hypoactive forms. CONCLUSIONS: In acute-care wards, frailty exhibited a strong association with delirium during hospitalization, while at the individual level, dementia and the use of antipsychotics remained important risk factors. Modern clinical prediction tools for delirium should account for frailty syndrome.
Assuntos
Delírio , Demência , Fragilidade , Humanos , Idoso , Idoso de 80 Anos ou mais , Fragilidade/complicações , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Idoso Fragilizado , Estudos Retrospectivos , Delírio/epidemiologia , Avaliação Geriátrica , Demência/epidemiologiaRESUMO
Impression materials are largely used to record the geometry of dental tissue. Hence, the assessment of their possible cytotoxicity is a necessary step in the evaluation of their biocompatibility. The present study is carried out to evaluate the cytotoxicity of a new elastomeric sterile and radiopaque impression material. Human gingival fibroblasts, cultured in vitro are exposed directly to Elite Implant in three different viscosities, heavy, medium, and light. At 3, 9, 24, 48, and 72 h, the cellular proliferation is evaluated. In parallel, human gingival fibroblasts are exposed indirectly by means of fluid extracts of Elite Implant. The cellular viability is evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide, (MTT) assay (Sigma, St Louis, Mo). The gingival fibroblasts proliferation and viability are unaffected by the presence of Elite Implant. This new impression material may represent a safe medical device for clinical and surgical applications. In addition, this material is radiopaque and, thus, can be identified radiographically.