Síntese e caracterização de cristais liquidos tipo bastão de hockey

TCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Físicas e Matemáticas. Curso de Química.Este trabalho tem como objetivo geral a síntese de cristais líquidos termotrópicos, com forma semelhante a bastões de hockey contendo o heterociclo 1,3,4 oxadiazol, e o estudo sistemático envolvendo a relação da estrutura molecular e comportamento mesomórfico bem como o fotofísico. O acesso à tais compostos envolve a reação de acoplamento cruzado de Sonogashira. As mesofases foram caracterizadas por observações ópticas de microscopia óptica de luz polarizada (MOLP) e medidas calorimétricas com um Calorímetro Diferencial de Varredura (DSC). As texturas observadas são típicas de cristais líquidos calamíticos. Todos os compostos foram caracterizados por métodos espectroscópicos de IV, UV, RMN de 1H e 13C

Cristais líquidos colunares luminescentes com arquiteturas helicoidais

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Química, Florianópolis, 2011Neste trabalho, foram projetadas duas famílias inéditas de ácidos carboxílicos com estrutura curvada, sendo uma simétrica e a outra assimétrica, derivadas do heterociclo 1,3,4-oxadiazol. Os ácidos foram caracterizados utilizando diversas técnicas espectroscópicas e espectrométricas. A partir dos ácidos carboxílicos e uma melamina foram preparados complexos supramoleculares através de ligações de hidrogênio em relação 1:3. Os complexos foram estudados por IV, RMN e DOSY. As propriedades térmicas foram investigadas por DSC, TGA, MOLP e SAXS. Todos os complexos supramoleculares apresentaram mesofase. Os DSCs mostraram mesofases monotrópicas, mantendo-se sem cristalizar até 25°C. As estruturas das mesofases foram determinadas por SAXS, onde caracterizou-se como fases colunares. Complexos quirais foram estudados por DC, obtendo-se intensos sinais. Os dados permitem propor que esses materiais podem assumir arquiteturas helicoidais. As propriedades fotofísicas foram avaliadas em solução, fase sólida e mesofase. Os materiais apresentaram absorbância entre 230-360 nm e emissão entre 370-540 nm. Estudos de elipsometria apresentaram valores significativos de emissão de LCP para os complexos quirais. Isso permite propor que materiais que apresentam mesomorfismo colunar organizados na forma de hélices podem ser utilizados para modulação da emissão de luz

beyond reported deaths

© 2020 The Authors. Published by Atlantis Press International B.V.BACKGROUND: One month after the first COVID-19 infection was recorded, Portugal counted 18,051 cases and 599 deaths from COVID-19. To understand the overall impact on mortality of the pandemic of COVID-19, we estimated the excess mortality registered in Portugal during the first month of the epidemic, from March 16 until April 14 using two different methods. METHODS: We compared the observed and expected daily deaths (historical average number from daily death registrations in the past 10 years) and used 2 standard deviations confidence limit for all-cause mortality by age and specific mortality cause, considering the last 6 years. An adapted Auto Regressive Integrated Moving Average (ARIMA) model was also tested to validate the estimated number of all-cause deaths during the study period. RESULTS: Between March 16 and April 14, there was an excess of 1255 all-cause deaths, 14% more than expected. The number of daily deaths often surpassed the 2 standard deviations confidence limit. The excess mortality occurred mostly in people aged 75+. Forty-nine percent (49%) of the estimated excess deaths were registered as due to COVID-19, the other 51% registered as other natural causes. CONCLUSION: Even though Portugal took early containment measures against COVID-19, and the population complied massively with those measures, there was significant excess mortality during the first month of the pandemic, mostly among people aged 75+. Only half of the excess mortality was registered as directly due do COVID-19. KEY POINTS: An Excess Mortality (EM) of 1255 deaths were estimated 1 month after the first death classified by COVID-19, and it would probably be more if the government had not taken early action. The age group where a significant increase in mortality was noted was above 75 years. 51% of the EM was due to natural causes other than COVID-19.publishersversionpublishe

Performance of the model called AcquaNetXL in the allocation of water in complex water resource systems

Este artigo apresenta uma ferramenta para análise de sistemas complexos de recursos hídricos denominada AcquaNetXL, que foi desenvolvida no formato de planilha eletrônica, na qual foram incorporados dois modelos de otimização, um linear e outro não linear. Essa ferramenta mantém os conceitos e os atributos de um sistema de suporte a decisão, ou seja, possui as características de estreitar a comunicação entre o usuário e o computador, de facilitar o entendimento, a formulação do problema, a interpretação dos resultados de análise e auxiliar no processo de tomada de decisão, tornando-o mais ordenado, objetivo e transparente. O desempenho do algoritmo utilizado na solução dos problemas de alocação de água foi satisfatório, especialmente para o modelo linear.This article presents a tool for the allocation analysis of complex systems of water resources, called AcquaNetXL, developed in the form of spreadsheet in which a model of linear optimization and another nonlinear were incorporated. The AcquaNetXL keeps the concepts and attributes of a decision support system. In other words, it straightens out the communication between the user and the computer, facilitates the understanding and the formulation of the problem, the interpretation of the results and it also gives a support in the process of decision making, turning it into a clear and organized process. The performance of the algorithms used for solving the problems of water allocation was satisfactory especially for the linear model

Years of life lost by COVID-19 in Portugal and comparison with other European countries in 2020

Funding Information: The present publication was funded by NOVA National School of Public Health and Fundação Ciência e Tecnologia, IP national support through CHRC (UIDP/04923/2020). Publisher Copyright: © 2021, The Author(s).Background: The impact of the COVID-19 pandemic has been measured in different metrics, mostly by counting deaths and its impact on health services. Few studies have attempted to calculate years of life lost (YLL) to COVID-19 and compare it with YLL due to other causes in different countries. Methods: We calculated YLL to COVID-19 from week10 to week52 in 2020 for eight European countries by methods defined by the WHO. We calculated excess YLL by subtracting the average YLL from 2017 to 2019 to the YLL in 2020. Our analysis compared YLL to COVID-19 and the excess YLL of non-COVID-19 causes across countries in Europe. Results: Portugal registered 394,573 cases and 6619 deaths due to COVID-19, accounting for 25,395 YLL in just 10 months. COVID-19 was responsible for 6.7% of all deaths but accounted for only 4.2% of all YLL. We estimate that Portugal experienced an excess of 35,510 YLL (+ 6.2%), of which 72% would have been due to COVID-19 and 28% due to non-COVID-19 causes. Spain, Portugal, and the Netherlands experienced excess YLL to non-COVID-19 causes. We also estimated that Portugal experienced an excess of 10,115 YLL due to cancer (3805), cardiovascular diseases (786) and diseases of the respiratory system (525). Conclusion: COVID-19 has had a major impact on mortality rates in Portugal, as well as in other European countries. The relative impact of COVID-19 on the number of deaths has been greater than on the number of YLL, because COVID-19 deaths occur mostly in advanced ages.publishersversionpublishe

Um mês em tempos de COVID-19

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seven months after the first death

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PHYSICAL-MECHANICAL PROPERTIES OF BRIQUETTES PRODUCED FROM CHARCOAL FINES AND WASTE OF Pinus spp.

The objective of this research was to evaluate the physical and mechanical properties of briquettes produced with charcoal fines and waste of Pinus spp (sawdust and wood shavings). For the production, the charcoal fines of two particle sizes (less than and greater than 5 mm) were mixed with each type of wood waste of Pinus spp in the proportions of 5, 10, 15, and 20%. Then, the mixtures were compacted under the pressure of 55 kgf.cm-2 in a piston briquetter. As binder, 8% gelatinized maize starch was used. Tests were carried out on the briquettes in order to determine the apparent density, compressive strength, and friability index. Briquettes with the highest densities and compressive strengths were produced with the two lowest proportions of wood waste of Pinus spp (5 and 10%). The use of the charcoal fines combined with sawdust or wood shavings of Pinus spp is recommended for the production of briquettes with good physical and mechanical properties.The objective of this research was to evaluate the physical and mechanical properties of briquettes produced with charcoal fines and waste of Pinus spp (sawdust and wood shavings). For the production, the charcoal fines of two particle sizes (less than and greater than 5 mm) were mixed with each type of wood waste of Pinus spp in the proportions of 5, 10, 15, and 20%. Then, the mixtures were compacted under the pressure of 55 kgf.cm-2 in a piston briquetter. As binder, 8% gelatinized maize starch was used. Tests were carried out on the briquettes in order to determine the apparent density, compressive strength, and friability index. Briquettes with the highest densities and compressive strengths were produced with the two lowest proportions of wood waste of Pinus spp (5 and 10%). The use of the charcoal fines combined with sawdust or wood shavings of Pinus spp is recommended for the production of briquettes with good physical and mechanical properties

possible impact of healthcare burden and hospital bed occupancy on clinical management and outcomes, March-December 2020

Copyright © 2023 Ricoca Peixoto, Vieira, Aguiar, Carvalho, Thomas, Sousa, Nunes and Abrantes.AIM: Identify factors associated with COVID-19 intensive care unit (ICU) admission and death among hospitalized cases in Portugal, and variations from the first to the second wave in Portugal, March-December 2020. INTRODUCTION: Determinants of ICU admission and death for COVID-19 need further understanding and may change over time. We used hospital discharge data (ICD-10 diagnosis-related groups) to identify factors associated with COVID-19 outcomes in two epidemic periods with different hospital burdens to inform policy and practice. METHODS: We conducted a retrospective cohort study including all hospitalized cases of laboratory-confirmed COVID-19 in the Portuguese NHS hospitals, discharged from March to December 2020. We calculated sex, age, comorbidities, attack rates by period, and calculated adjusted relative risks (aRR) for the outcomes of admission to ICU and death, using Poisson regressions. We tested effect modification between two distinct pandemic periods (March-September/October-December) with lower and higher hospital burden, in other determinants. RESULTS: Of 18,105 COVID-19 hospitalized cases, 10.22% were admitted to the ICU and 20.28% died in hospital before discharge. Being aged 60-69 years (when compared with those aged 0-49) was the strongest independent risk factor for ICU admission (aRR 1.91, 95%CI 1.62-2.26). Unlike ICU admission, risk of death increased continuously with age and in the presence of specific comorbidities. Overall, the probability of ICU admission was reduced in the second period but the risk of death did not change. Risk factors for ICU admission and death differed by epidemic period. Testing interactions, in the period with high hospital burden, those aged 80-89, women, and those with specific comorbidities had a significantly lower aRR for ICU admission. Risk of death increased in the second period for those with dementia and diabetes. DISCUSSION AND CONCLUSIONS: The probability of ICU admission was reduced in the second period. Different patient profiles were identified for ICU and deaths among COVID-19-hospitalized patients in different pandemic periods with lower and higher hospital burden, possibly implying changes in clinical practice, priority setting, or clinical presentation that should be further investigated and discussed considering impacts of higher burden on services in health outcomes, to inform preparedness, healthcare workforce planning, and pandemic prevention measures.publishersversionpublishe

Excesso de mortalidade, em Portugal, em tempos de COVID-19

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