65 research outputs found
UTILIZAÇÃO DE FERRAMENTAS DE APOIO À TOMADA DE DECISÃO COMO SUPORTE AO PLANEJAMENTO INTEGRADO DE RECURSOS ENERGÉTICOS (PIR): IMPLICAÇÕES E SOLUÇÕES PARA O ESTADO DO ESPÍRITO SANTO
A abordagem do Planejamento Integrado de Recursos (PIR) é aquela que considera opções tanto do lado da oferta como da demanda para satisfazer a necessidade de diferentes recursos energéticos, ao mesmo tempo em que busca minimizar os custos resultantes para as empresas e para a sociedade. Esta pesquisa buscou fazer uso de ferramentas que permitam auxiliar o tomador de decisão na realização do PIR para o setor de energia do Espírito Santo, tendo em conta os problemas existentes para diversificação da matriz renovável do estado e analisando as melhores práticas em curso nos países que se destacam neste segmento. Por meio de uma análise SWOT, é feito um levantamento das oportunidades que o PIR pode oferecer em locais com potencial energético comprovado, confrontando-as com as barreiras existentes a esse processo. Em seguida, fazendo uso de relações de Causa/Efeito/ Resposta, são discutidas propostas de mecanismos de atuação que podem auxiliar a abordagem PIR a ser empregada de maneria útil no estado através dos agentes e os instrumentos apresentados, nos locais que foram identificados, para minimizar os problemas do setor da energia, tendo em vista que este tipo de abordagem mostrou benefícios perceptíveis em outras localidades do país e fora dele
Fuel cell powered octocopter for inspection of mobile cranes: Design, cost analysis and environmental impacts
Hydrothermally-assisted recovery of Yttria- stabilized zirconia (YSZ) from end-of-life solid oxide cells
Effective and scalable recycling strategies for the recovery of critical raw materials are yet to be validated for solid oxide cells (SOCs) technologies. The current study aimed at filling this gap by developing optimized recycling processes for the recovery of Yttria-stabilized Zirconia (YSZ) from End-of-Life (EoL) SOC components, in view of using the recovered ceramic phase in cell re-manufacturing. A multi-step procedure, including milling, hydrothermal treatment (HT), and acidic-assisted leaching of nickel from composite Ni-YSZ materials, has been implemented to obtain recovered YSZ powders with defined specifications, in terms of particle size distribution, specific surface area, and chemical purity. The overall optimized procedure includes a pre-milling step (6 h) of the EoL composite materials, and a hydrothermal (HT) treatment at 200 °C for 4 h to further disaggregate the sintered composite, followed by selective oxidative leaching of Ni2+ by HNO3 solution at 80 °C for 2 h. In particular, the intermediate HT step was assessed to play an essential role in promoting the disaggregation of the sintered powders, with a related increase of specific surface area (up to 13 m2 g−1) and the overall reduction of the primary particle aggregates. The acid-assisted leaching allowed to fully extract Nickel from the composite Ni-YSZ powders, with retention of YSZ crystallinity and negligible loss of Zr and Y, as revealed by ICP analysis on the recovered supernatants. The developed multi-step pathway offers a promising strategy to recover valuable YSZ materials for the re-manufacturing of SOCs components, with the aim to boost a circular economy approach in the field of fuel-cell and hydrogen (FCH) technologies
Decline in subarachnoid haemorrhage volumes associated with the first wave of the COVID-19 pandemic
BACKGROUND: During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study\u27s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines.
METHODS: We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March-31 May 2020. The prior 1-year control period (1 March-31 May 2019) was obtained to account for seasonal variation.
FINDINGS: There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI -24.3% to -20.7%, p\u3c0.0001). Embolisation of ruptured aneurysms declined with 1170-1035 procedures, respectively, representing an 11.5% (95%CI -13.5% to -9.8%, p=0.002) relative drop. Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations, a 24.9% relative decline (95% CI -28.0% to -22.1%, p\u3c0.0001). A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1% (95% CI 32.3% to 50.6%, p=0.008) despite a decrease in SAH admissions in this tertile.
INTERPRETATION: There was a relative decrease in the volume of SAH hospitalisations, aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic. These findings in SAH are consistent with a decrease in other emergencies, such as stroke and myocardial infarction
Evaluation of appendicitis risk prediction models in adults with suspected appendicitis
Background
Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis.
Methods
A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis).
Results
Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent).
Conclusion
Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified
American College of Rheumatology Provisional Criteria for Clinically Relevant Improvement in Children and Adolescents With Childhood-Onset Systemic Lupus Erythematosus
10.1002/acr.23834ARTHRITIS CARE & RESEARCH715579-59
Retrieval of blade implants with piezosurgery: two clinical cases.
In this work an ultrasound device was used to perform an ostectomy for the removal of blade implants in order to save as much bone tissue as possible, so that root form implants might later be inserted. Two patients underwent surgery for the removal of two blade implants (one maxillary, the other mandibular) that were no longer functional. The peri-implant ostectomy was carried out with a piezoelectric surgery device. The instrument demonstrated to be effective and precise during ostectomy, providing an extremely thin cutting line. During the course of the operation and at controls after 7 and 30 days, patients did not show any relevant complications and both still had sufficient alveolar bone to be treated with root form implants. The piezosurgery device proved to be an effective instrument in interventions requiring a significant saving of bone tissue, extreme precision in cutting, and respect of soft tissues
Differential complexes and stratified pro-modules
In this paper we introduce the category of stratified pro-modules and the notion of induced object in this category. We propose a translation of Saito equivalence results (Bull. Soc. Math France 117:361–387, 1989) using the dual language of pro-objects. So we prove an equivalence between the derived category of stratified pro-modules and the category of prodifferential complexes. We also supply a comparison with the notion of crystal in pro-module (introduced by P. Deligne in 1970)
Imprinting Pentaphyrin on Conductive Electropolymerized Dipyrromethane Films: A New Strategy towards the Synthesis of Photokilling Materials
We report herein the synthesis and photoinduced bactericidal activity of two new polymeric materials, obtained by imprinting the photosensitizer 20-(4-carboxyphenyl)-2,13-dimethyl-3,12-diethyl-[22]pentaphyrin (PCox, 1) into suitable electropolymerized dipyrromethane films. 5-Phenyl-dipyrromethane (5-ph-DP) and 5-(4-pyridyl)dipyrromethane (5-py-DP) have been selected as the monomers for the synthesis of the materials in order to assess the correlation between the substituent in C5 and the capability in Pcox uptake. Both films have been tested in their photokilling ability toward Staphylococcus aureus by using a multi-LED blue lamp at a fluence rate of 40 W/m2. Poly-5-py-DP/PCox, with a PCox load of 10 128 mol/cm2, achieved a 4-log reduction in microbial viability after 60 min of irradiation. The polymeric films proved to be stable over time and under oxidation conditions; in addition, no loss of photosensitizer was observed during the experiments, thus demonstrating that the bactericidal action was effectively brought by the ROS generated by PCox immobilized in the material. After use, the films were recharged with PCox, with almost complete recovery of their photodynamic efficiency
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