Ecological payback in national energy matrix: analysis of wind energy expansion

Sustainable development concern has become subject of recurrent discussions over the last years due to the duet large greenhouse gases emissions and world growth, especially in developing countries. Electrical sector is one of the major segments responsible for greenhouse gases emissions, but also the one in which modern society depends the most for life standard maintenance, economic and social activities. A renewable source considered in Brazilian energy sector expansion is wind power, which has a 143 GW potential. As such, the paper aims to estimate environmental impacts (CO2 emission) involved in wind power plants construction phase and return time for compensating these emissions during operation. Ecological payback is developed through CO2 emission analysis of different energy sectors required as inputs in construction and final emission reduction due to this “clean” power plant operation in national electrical matrix. Estimation of economic and environmental impacts is based on input-output methodology, using a 2004 matrix for Brazilian economy. Results point out for a maximum payback period of 4 months in worst case scenario, and major pollution contribution of Steel and Products Manufacturing during construction.Input-Output; Environmental Sustainability; Energy Economics; Wind Energy

Ecological payback in Brazil energy matrix: analysis of a wind energy expansion

Sustainable development concern has become subject of recurrent discussions over the last years due to the duet large greenhouse gases emissions and world growth, especially in developing countries. Electrical sector is one of the major segments responsible for greenhouse gases emissions, but also the one in which modern society depends the most for life standard maintenance, economic and social activities. A renewable source considered in Brazilian energy sector expansion is wind power, which has a 143 GW potential. As such, the paper aims to estimate environmental impacts (CO2 emission) involved in wind power plants construction phase and return time for compensating these emissions during operation. Ecological payback is developed through CO2 emission analysis of different energy sectors required as inputs in construction and final emission reduction due to this “clean” power plant operation in national electrical matrix. Estimation of economic and environmental impacts is based on input-output methodology, using a 2004 matrix for Brazilian economy. Results point out for a maximum payback period of 4 months in worst case scenario, and major pollution contribution of Steel and Products Manufacturing during construction.Input-Output; Environmental Sustainability; Energy Economics; Wind Energy; Brazil

A prevalência da linearidade nas relações entre os conceitos de perímetro, área e volume

No presente estudo teve-se como principal propósito conhecer, descrever e interpretar os processos desenvolvidos pelos alunos na resolução de tarefas envolvendo relações entre os conceitos de perímetro, área e volume. Participaram no estudo duas turmas, uma do 6.º ano e outra do 9.º ano, cada uma com 26 alunos. A recolha de dados foi efectuada através de um teste, incluindo questões sobre os conceitos de perímetro, área, volume e suas relações. Em termos de resultados, verificou-se que a grande maioria dos alunos, quer do 6.º ano quer do 9º ano, estabeleceu relações lineares entre os conceitos, as quais conduziram sempre a respostas correctas quando se tratava de relações entre perímetros e a respostas incorrectas quando se tratava de relações entre áreas e entre volumes. Entre os dois anos escolares não se salientaram diferenças significativas no tipo de respostas dadas e nas estratégias usadas

Degenerescência aneurismática na doença de Von Recklinghausen

ResumoA doença de Von Recklinghausen é uma facomatose de transmissão autossómica dominante. Apesar da heterogeneidade da expressão clínica, os estigmas cutâneos clássicos como manchas café au lait são frequentes. A arteriopatia é incomum, sendo a degenerescência aneurismática extremamente rara.Os autores apresentam o caso clínico de um homem de 63 anos com doença de Von Recklinghausen e degenerescência multianeurismática aorto‐ilíaca, femoral e poplítea, submetido com sucesso a tratamento cirúrgico convencional.A degenerescência aneurismática na doença de Von Recklinghausen encontra‐se associada a displasia muscular lisa e a invasão neurofibromatosa da parede vascular. Esta fragilidade arterial implica dissecção laboriosa e técnica cirúrgica meticulosa para limitar a hemorragia e a deiscência anastomótica.AbstractThe Von Recklinghausen's disease is a facomatosis with autosomal dominant transmission. Despite the heterogeneity of clinical expression, the classic cutaneous stigmata such as café au lait spots are common. The arteriopathy is unusual, with rare aneurysmal degeneration.The authors disclose the clinical case of a 63 years old man with Von Recklinghausen's disease and multi‐aneurysmal degeneration of the aorto‐iliac, femoral and popliteal sectors, who successfully underwent open surgery.The aneurysmal degeneration in Von Recklinghausen's disease is associated with smooth muscle dysplasia and neurofibromatosis invasion of the vascular wall. This arterial fragility implies laborious and meticulous surgical dissection to limit the bleeding and anastomotic dehiscence

Antibioterapia profilática na extração de terceiros molares inclusos

Contextualização: A extração de terceiros molares é um dos atos clínicos mais realizados em Cirurgia Oral. A presença de um terceiro molar incluso pode estar na origem de uma variedade de complicações. Pericoronarite, cáries dentárias e doença periodontal são algumas das indicações para extração de terceiros molares inclusos. A antibioterapia profilática para a prevenção de complicações pós-operatórias como a alveolite e a infeção do local cirúrgico é ainda um assunto que gera alguma controvérsia, particularmente em indivíduos saudáveis. Objetivo: Estudar a necessidade da antibioterapia profilática na extração de terceiros molares e os seus potenciais riscos e benefícios. Materiais e Métodos: Foi efetuada uma pesquisa bibliográfica na base de dados da MEDLINE/PubMed e no motor de busca da ResearchGate. Adicionalmente, foram coletados artigos de interesse da bibliografia recolhida e consultados alguns livros de forma a complementar a informação obtida. Conclusão: Não existe um consenso no que toca à profilaxia antibiótica na extração de terceiros molares. Os médicos dentistas devem, por isso, efetuar uma avaliação cuidada do estado clínico de cada paciente de forma a tomar uma decisão consciente relativamente à administração de antibióticos com o intuito de prevenir complicações pós-operatórias da cirurgia de terceiros molares inclusos.Background: Third molar extraction is one of the most frequent clinical procedures in Oral Surgery. The presence of an impacted third molar may be at the root of various issues. Pericoronitis, dental caries and peridontal disease are some of the indications for the removal of impacted third molars. Antibiotic prophylaxis for preventing postoperative complications, such as alveolar osteitis and surgical site infections, is still a controversial topic, especially in healthy individuals. Aim: To study the need for antibiotic prophylaxis when extracting impacted third molars and its potential risks and benefits. Material and Methods: A literature search was conducted in the MEDLINE/PubMed database and the ResearchGate search engine. Additionally, various relevant articles were collected from the compiled literature references, as well as some books, in order to further expand on the obtained information. Conclusion: There is currently no consensus in regard to the use of antibiotic prophylaxis when extracting third molars. As such, dentists should carefully assess each patient’s clinical profile so that an informed decision can be made, in relation to the use of antibiotics in order to prevent postoperative complications from impacted third molar surgery

Desempenho de alunos de engenharia em testes de hipóteses

Neste trabalho analisamos o desempenho de 223 alunos da Licenciatura de Engenharia Informática do Instituto Superior de Engenharia do Porto, no ano letivo 2012-2013, quando confrontados com várias questões sobre testes de hipóteses. Em termos de resultados, os alunos apresentaram muitas dificuldades no tema, a maior parte das quais similares às que são relatadas na literatura.info:eu-repo/semantics/publishedVersio

Prescribed burning mitigates the severity of subsequent wildfires in Mediterranean shrublands

[EN] Background Prescribed burning (PB) is becoming relevant in fuel reduction and thus fire hazard abatement in fire‑prone ecosystems of southern Europe. Yet, empirical evidence on the effectiveness of this practice to mitigate wildfire severity in Mediterranean shrublands is non‑existent, despite being the focus of PB efforts in this region. Here, we intended to quantify the protective effect of PB treatment units (2005–2021) to subsequent wildfire severity in shrublands across mainland Portugal, as well as the relative contribution and complex interactions between drivers of wildfire severity in PB‑treated areas and untreated neighboring counterparts through Random Forest regression. We leveraged cloud‑computing remote sensing data processing in Google Earth Engine to estimate fire severity (PB and wildfire) as the Relativized Burn Ratio (RBR) using Landsat data catalog.Results PB treatment was particularly effective at mitigating wildfire severity at the first PB‑wildfire encounter in shrublands, with a mean reduction of around 24% in RBR units. Fuel age (i.e., time since prescribed burning) in PB‑wildfire intersection areas overwhelmed to a large extent the effect of fire weather, burning probability, and PB severity. The mitigating effect of PB on wildfire severity persisted for a fuel age of around 5 years. However, this effect decreased with increasingly adverse fire weather conditions, such that variation in wildfire severity was somewhat insensitive to fuel age under extreme fire weather. Similarly, the lowest wildfire severity experienced in sites with high burning probability, along with the interaction effect observed between burning probability and fuel age, suggest that repeated PB treatments may be useful in controlling fuel accumulation and mitigating wildfire severity. The relative contribution of fire weather in explaining wildfire severity was exceedingly high in untreated areas, doubling that of the other variables in the model in the absence of PB treatment variables.Conclusions Our results suggest that the implementation of PB treatments at intervals of less than 5 years is of para‑mount importance to control fuel build‑up and fire hazard under extreme fire weather in productive Mediterranean shrublands. Further research on this topic is warranted in other shrublands worldwide, namely in Mediterranean‑type climate regions[ES] Antecedentes: Las quemas prescritas (PB) se han tornado relevantes en la reducción de combustibles y por lo tanto en la disminución del riesgo de incendios en ecosistemas proclives al fuego. Así todo, la evidencia empírica sobre la efectividad de esta práctica para mitigar la severidad del fuego en matorrales de ecosistemas del Mediterráneo es inexistente, a pesar de ser el foco de los esfuerzos de las PB en la región. En este trabajo, intentamos cuantificar el efecto protector en unidades de tratamientos de PB (2005‑2021) sobre la severidad subsecuente de incendios en matorrales a lo largo del centro de Portugal, como así también, la contribución relativa e interacciones complejas entre los factores conducentes a la severidad del fuego en áreas tratadas con PB y aquellas vecinas sin tratar (PB y No tratadas), a través de regresión Random Forest. Utilizamos la capacidad de procesamiento de sensores remotos en Google Earth Engine para estimar tanto la severidad del fuego (en PB y áreas no tratadas ) como la Ratio Relativa de Quemado (Relativized Burn Ratio, RBR) usando los datos del catálogo de Landsat. Resultados: Los tratamientos de PB fueron efectivos para mitigar los efectos de severidad del fuego en las primeras interacciones de PB con áreas incendiadas no tratadas, con una reducción media de alrededor del 24% en unidades de RBR. La edad del combustible (i.e. el tiempo transcurrido desde la PB) en la intersección PB‑incendio superó en gran medida los efectos de la meteorología del incendio, la probabilidad de quema, y la severidad de la PB. El efecto mitigador de la PB en la severidad de los incendios persistió en el combustible por unos 5 años luego de la PB. Desde luego, este efecto decreció con el incremento de condiciones adversas en la meteorología del incendio, tal como que la variación en la severidad del incendio fue no sensible a la edad del combustible bajo condiciones meteorológicas extremas. Similarmente, las severidades más bajas experimentadas en sitios con alta probabilidad de quema, junto con los efectos de las interacciones observadas entre probabilidad de quema y la edad del combustible, sugiere que la repetición de los tratamientos de PB puede ser útil para controlar la acumulación de combustible y mitigar la severidad de los incendios. La contribución relativa de las condiciones meteorológicas en la severidad del fuego fue notablemente alta en áreas no tratadas, duplicando el efecto de otras variables del modelo en ausencia de las variables de las PB. Conclusiones: Nuestros Resultados sugieren que la implementación de tratamientos de PB a intervalos menores de 5 años es de una alta importancia para controlar la acumulación de combustible y reducir el riesgo de incendios bajo eventos meteorológicos extremos en matorrales de ecosistemas Mediterráneos. Más investigaciones en este tema deben garantizarse en otros matorrales del mundo, fundamentalmente en aquellos que se desarrollan bajo climas de tipo MediterráneoSIThis study was financially supported by the Portuguese Foundation for Science and Technology in the frame of project UIDB/04033/2020. José Manuel Fernández-Guisuraga was supported by a Ramón Areces Foundation postdoctoral fellowshi