Measuring kidney transplantation activity

[ENG] Kidney allocation from cadaveric donors must balance two main principles: medical utility and justice. The principle of medical benefit is gauged by maximizing efficiency in the use of organs and the principle of justice by its effectiveness, ensuring that all patients have a reasonable opportunity of transplantation. In this paper we present some metrics that, when applied to candidates for kidney transplantation, will help in the best judgment defining kidney allocation systems. Knowing the prevalence and incidence (per year, per million inhabitants) of kidney transplant, candidates demographic factors, such as: sex, age groups, and socioeconomic status; as well as clinical and immunological characteristics: blood group, Panel Reactive Antibody values, Body Mass Index, type of dialysis, cause of renal failure, and comorbidities; allows for an objective comparison of allocation programmes. The waiting time for transplantation should be measured as the median time between the start of dialysis and transplantation of wait -listed patients each year. By using the Cox regression analysis, with time on dialysis for transplantation as a dependent variable and clinical, socio -demographic factors as independent variables, we will shed light on which characteristics affect the access to transplantation.[PT] A distribuição de rins de dador cadáver deve equilibrar dois princípios fundamentais: a utilidade médica e a justiça. O principio do beneficio médico e aferido através da maximização da eficiência no uso dos órgãos, enquanto que o principio da justiça visa garantir que todos os candidatos tenham uma oportunidade razoável de transplante. Neste artigo, apresentamos algumas métricas que, quando aplicadas a candidates a transplante de rim, ajudarão na melhor avaliação e definição de sistemas de distribuição de rins. Conhecer a prevalência e incidência (por ano e por milhão de habitantes) dos transplantes de rim, fatores demográficos dos candidatos, tais como: sexo, faixa etária e nível socioeconómico; bem como as suas características clinicas e imunológicas: grupo sanguíneo, os valores do painel reativo de anticorpos, índice de massa corporal, tipo de dialise, a causa da insuficiência renal e co -morbilidades; permite uma comparação objetiva de programas distribuição. O tempo de espera para o transplante deve ser medido como a mediana do tempo entre o início da dialise e o transplante dos doentes em lista de espera em cada ano. Através da analise de regressão de Cox, com o tempo em dialise para transplante como variável dependente e os fatores clínicos e sócio-demográficos como variáveis independentes, e possível identificar as características que afetam o acesso ao transplante

Measuring access to Kidney transplantation

ORAL SESSIONS - Best AbstractsKidney allocation from cadaveric donors must balance two main principles: medical utility and justice. The principle of medical benefit is gauged by maximizing efficiency in the use of organs, and the principle of justice by its effectiveness ensuring that all patients have a reasonable opportunity to be transplanted. The survival benefit of transplant patients when compared with dialyzed values is well described even after adjusting for age, comorbidities, albumin and Body Mass Index (BMI). This benefit is also observed in patients over the age of 60 years. Several factors are related to transplant efficiency: maximization of HLA matching for patients that are more relevant (children and youth), preference for children; minimization of ischemia time, and the relation of life expectancy of the graft with life expectancy of the receptor. The factors related to justice are: reduction of waiting times, and greater equity of access for patients regardless of their race, blood group, HLA homozygosity and geographic location. There are socio-demographic and immunological factors associated with longer waiting time for kidney transplantation, such as: age, blood group or sensitization against HLA antibodies.Knowing the prevalence and incidence (per year, per million inhabitants) of kidney transplant candidates’ demographic factors such as: sex, age groups, socioeconomic status, clinical and immunological characteristics: blood group, PRA values, BMI, type of dialysis, cause of renal failure, and comorbidities; allows for an objective comparison of allocation programs. The waiting time for transplantation should be measured as the median time between the start of dialysis and transplantation of wait listed patients each year. By using the Cox regression analysis, with time on dialysis to transplantation as a dependent variable and clinical and socio-demographic factors as independent variables, will shed light on which characteristics most affect the access to transplantation. Only by defining and applying standardized metrics to kidney transplant candidates over time, is it possible to make informed decisions when debating organ allocation rules. “What gets measured gets improved”

Applying virtual crossmatch approach in portuguese kidney transplants

ORAL SESSIONS - Best AbstractsPresence of donor specific antibodies anti-human leukocyte antigen (HLA) is generally a contra-indication for transplantation and nowadays the identification of these antibodies are part of most pre-transplantation evaluations. In Portugal, the implemented protocol for the registration and maintenance of the active list for kidney transplant includes a complement-dependent cytotoxity (CDC) panel-reactive antibody (PRA) screening method, and Luminex technology for detecting and characterizing HLA alloantibodies. Under the current Portuguese kidney allocation system from deceased donors, implemented in August 2007, deceased donor kidneys are primarily allocated via ABO identical and time on dialysis with extra points to hyperimmunized patients, namely PRA CDC>50%. Additional risk for the candidate or transplant organ can be represented by a proposed calculated PRA (cPRA) based upon unacceptable HLA antigens detected by Luminex to which the patient has been sensitized. These unacceptable HLA antigens used to generate cPRA represents a ‘virtual’ crossmatch (XM). Sensitized patients are less likely to be matched with a suitable donor organ. Even after clearing the hurdle of procuring a living donor, it is still possible that this is not sufficient due to the likelihood of having a XM-positive. In these cases and in the presence of incompatible blood type between recipients and their intended living donors, kidney paired donation (KPD) can provide an answer by facilitating exchanges between willing donors’ kidneys. A national Portuguese KPD program, when realized, may prevent the current loss of a significant number of suitable living donors and reduce waiting list time for a deceased donor. An upgrade of a suggested point system in a Portuguese KPD program will be the use of cPRA instead of the values of PRA CDC. In Portugal, the virtual XM approach simply represents the optimization of an existing technique

Alocação de rins para transplante em Portugal

[ENG] Factors such as: patient age, place of residence, socioeconomic status, cause of kidney failure, prognosis, duration of dialysis and co-morbidities influence transplantation outcome. Also the quality of available donors must be taken into account when looking for the balance between utility and justice. In the USA, UK and Portugal deceased donor kidney allocation rules are based on systems of points assigned to each possible receptor. However, the key factor in organ allocation is time on dialysis (first come, first served basis). The discussion about access to kidney transplantation with deceased donors never comes to a close and must be done clearly and systematically in order to enable the best decisions at any given moment.[PT] Tendo em conta o fato de que o dador cadáver de órgãos é um bem escasso, a sua distribuição deve ser equilibrada, a fim de maximizar a utilidade e justiça. Um sistema de distribuição de rins de dador cadáver deverá ser alicerçado em políticas transparentes. Deve ter em conta a relação entre oferta e procura, buscando um equilíbrio entre o benefício neto mais elevado de sobrevivência que pode ser fornecido por um determinado órgão e o tempo de espera dos candidatos a transplante (assim como a probabilidade de estes serem transplantados). Fatores como: idade do doente, local de residência, nível socioeconómico, causa de insuficiência renal, o prognóstico, o tempo de diálise e co-morbilidades influenciam os resultados do transplante. Também a qualidade dos dadores disponíveis deve ser considerada quando se olha para o equilíbrio entre a utilidade e justiça na distribuição dos órgãos. Nos EUA, Reino Unido e Portugal as regras de alocação de rins de dadores cadáver são baseados em sistemas de pontos atribuídos a cada possível receptor. No entanto, o fator-chave na alocação de órgãos é o tempo em diálise (numa base: primeiro a chegar, primeiro a ser servido). A discussão sobre o acesso ao transplante renal de dador cadáver é constante e deve ser feita de forma clara e sistemática, de modo a permitir as melhores decisões em todos os momentos

Candidatos hipersensibilizados a transplantação renal em Portugal

[ENG] The presence of donor specific anti-HLA antibodies is generally a contraindication for transplantation and nowadays the identification of these antibodies are part of most pre-transplantation evaluations. In Portugal, the implemented protocol for registration and maintenance of the active list for kidney transplant includes a complement -dependent cytotoxity (CDC) panel-reactive antibody (PRA) screening method, and Luminex technology for detecting and characterizing HLA alloantibodies. Under the current Portuguese kidney allocation system from deceased donors, implemented in August 2007, deceased donor kidneys are primarily allocated via ABO identical and time on dialysis with extra points to hyperimmunized patients, namely PRA CDC > 50%. Additional risk for the candidate or transplant organ can be represented by a proposed calculated PRA (cPRA) based upon unacceptable HLA antigens detected by Luminex to which the patient has been sensitized. These unacceptable HLA antigens used to generate cPRA represents a virtual crossmatch (XM). Sensitized patients are less likely to be matched with a suitable donor organ. Even after clearing the hurdle of procuring a living donor, it is still possible that this is not sufficient due to the likelihood of having an XM-positive. In such cases, and in the presence of incompatible blood type between recipients and their intended living donors, kidney paired donation (KPD) can provide an answer to this catch by facilitating exchanges between willing donors kidneys. A national Portuguese KPD programme, when realized, may prevent the current loss of a significant number of suitable living donors and reduce waiting list time for a deceased donor. An upgrade of a suggested point system in a Portuguese KPD programme will be the use of cPRA instead of the values of PRA CDC. In Portugal, the virtual XM approach just represents the optimization of an existent technique.[PT] A presença de anticorpos anti-HLA específicos do dador é geralmente uma contraindicação para transplante e, hoje em dia, a identificação destes anticorpos é parte de muitos protocolos de avaliação pré--transplante. Em Portugal, o protocolo implementado para o registo e manutenção em lista activa para transplante de rim, inclui um método de pesquisa em painel reactivo de anticorpos (PRA) por citotoxicidade dependente do complemento (CDC) e a tecnologia Luminex para detectar e caracterizar aloanticorpos HLA. Segundo as actuais normas para a selecção do par dador-receptor em homotransplantação com rim de cadáver, implementadas em Agosto de 2007, a distribuição destes órgãos é prioritariamente isogrupal, contabilizando o tempo em diálise com pontos extra paras doentes imunizados, nomeadamente PRA CDC>50%. Um risco adicional para os candidatos a transplante de órgãos pode ser representado pelo proposto PRA calculado (cPRA), que tem por base antigénios HLA não aceitáveis, detectados por Luminex e para os quais os doentes estão sensibilizados. Estes antigénios HLA não aceitáveis usados para gerar o cPRA representam um crossmatch (XM) virtual. Os doentes sensibilizados têm uma menor probabilidade de encontrar um dador de órgãos admissível e mesmo depois de ultrapassada a barreira de encontrar um dador vivodisponível, é possível que isto não seja suficiente devido ao risco elevado de ter um XM positivo. Nestes casos e quando há incompatibilidade ABO entre um receptor e o seu potencial dador vivo, a troca de dadores vivos de rim (TDR) pode ser a resposta a este problema facilitando a consumação de transplantes compatíveis. Um programa nacional de TDR, quando implementado, pode evitar o actual desperdício de possíveis dadores vivos de rim e potencialmente reduzir o tempo de espera em lista para transplante com dador cadáver. Uma melhoria a um sugerido sistema de pontuação num programa Português de TDR será a utilização do cPRA em substituição dos valores de PRA CDC. Em Portugal, a abordagem de XM-virtual apenas representa a optimização de técnicas já existentes

The Impact of High Particles Concentration in a Biofuel Droplet Combustion

Aviation is one of the largest transportation sectors and is operated on fossil fuels, being responsible for about 2% of global CO2 emissions. In order to reduce the environmental impact, biofuels emerged as a promising solution. Additionally, a possible approach to improve the performance of biofuels is to add nanoparticles, leading to the concept of nanofuel. The present work evaluates the nanofuel droplet combustion of a biofuel containing high aluminum particle concentrations. To enhance the nanofuel stability, a preliminary study focusing on the addition of a surfactant was mandatory. Particle size of 40 nm and three particle concentrations from 1.0 to 4.0 wt.% were considered. The results show that the oleic acid effectively improves the stability, and no visible oxidation of the nanoparticles was reported. Regarding the single droplet combustion, the observations show that the addition of nanoparticles promotes micro-explosions, contrary to the combustion of pure biofuel, and increases the overall droplet burning rate.Fundação para a Ciência e a Tecnologiainfo:eu-repo/semantics/publishedVersio

The Addition of Particles to an Alternative Jet Fuel

The expansion of the research on nanoscale particles demonstrates several advantages in terms of stability and an increased surface area to volume ratio compared to micron-sized particles. Based on this, the present work explores the addition of aluminum particles in hydrotreated vegetable oil (HVO), an alternative jet fuel. To evaluate the influence of particle sizes, nano and micron particles (40 nm and 5 μm) in a particle concentration of 0.5 wt.% were stably suspended in HVO. This study evaluates droplet combustion with an initial diameter of 250 μm in a drop tube furnace under different furnace temperatures (600, 800, 1000 °C). A high magnification lens coupled with a high-speed camera provides qualitative and quantitative data regarding droplet size evolution and micro-explosions. Pure HVO and Jet A-1 were also tested for comparison purposes. The results reveal that the addition of aluminum particles enhances the alternative jet fuel combustion. Furthermore, decreasing the particle size and increasing the furnace temperature enhances the burning rate compared to the pure HVO. Pure HVO presents a burning rate nearly to 1.75 mm2/s until t/D20 = 0.35 s/mm2 at T = 1000 °C. When nanoparticles are added to HVO in a particle concentration of 0.5 wt.%, an improvement of 24% in burning rate is noticed. Conventional jet fuel and pure HVO do not present any disruptive burning phenomena. However, when aluminum particles were added to HVO, micro-explosions were detected at the end of droplet lifetime, regardless of the particle size.Fundação para a Ciência e a Tecnologiainfo:eu-repo/semantics/publishedVersio

Experimental Investigation Of Disruptive Burning Phenomena On Nanofuel Droplets

The transport sector plays a crucial aspect in society and economic evolution. However, improper energy management has negatively impacted health and the environment. Thus, the use of sustainable and green fuels in the aeronautical industry has been implemented due to environmental concerns and the depletion of fossil fuels. The introduction of biofuels, a renewable energy source in the transportation sector, has shown advantages in terms of pollutant reduction. Recently, the addition of nanoparticles in the combustion of biofuel has been studied with the purpose of enhancing its combustion characteristics. Consequently, the present work evaluates nanofuel single droplet in a falling droplet method. In this way, the fiber suspension effect was neglected, and droplets in a size of 250 μm were evaluated. To this end, a comparison between pure biofuel and a nanofuel at two furnace temperatures (T = 800 ºC and T = 1000 ºC) was performed. The results reveal that disruptive burning phenomena occur when aluminum nanoparticles are added to the biofuel. Consequently, a micro-explosion determines the end of the droplet lifetime, mainly affected by the furnace temperature.Fundação para a Ciência e a Tecnologiainfo:eu-repo/semantics/publishedVersio

Innovative moments in grief therapy: reconstructing meaning following perinatal death

This article presents an intensive analysis of a good outcome case of constructivist grief therapy with a bereaved mother, using the Innovative Moments Coding System (IMCS). Inspired by M. White and D. Epston’s narrative therapy, the IMCS conceptualizes therapeutic change as resulting from the elaboration and expansion of unique outcomes (or as we prefer, innovative moments), referring to experiences not predicted by the problematic or dominant self-narrative. The IMCS identifies and tracks the occurrence of 5 different types of innovative moments: action, reflection, protest, re-conceptualization, and performing change. Results documented the process of meaning reconstruction over the 6 sessions of treatment, and demonstrated the feasibility and reliability of analyzing narrative change in this form of grief therapy, opening it to comparison with other approaches

Deep Learning Framework for Controlling Work Sequence in Collaborative Human–Robot Assembly Processes

project UIDB/EMS/00667/2020 (UNIDEMI)The human–robot collaboration (HRC) solutions presented so far have the disadvantage that the interaction between humans and robots is based on the human’s state or on specific gestures purposely performed by the human, thus increasing the time required to perform a task and slowing down the pace of human labor, making such solutions uninteresting. In this study, a different concept of the HRC system is introduced, consisting of an HRC framework for managing assembly processes that are executed simultaneously or individually by humans and robots. This HRC framework based on deep learning models uses only one type of data, RGB camera data, to make predictions about the collaborative workspace and human action, and consequently manage the assembly process. To validate the HRC framework, an industrial HRC demonstrator was built to assemble a mechanical component. Four different HRC frameworks were created based on the convolutional neural network (CNN) model structures: Faster R-CNN ResNet-50 and ResNet-101, YOLOv2 and YOLOv3. The HRC framework with YOLOv3 structure showed the best performance, showing a mean average performance of 72.26% and allowed the HRC industrial demonstrator to successfully complete all assembly tasks within a desired time window. The HRC framework has proven effective for industrial assembly applicationspublishersversionpublishe