Reliability Estimation Using EM Algorithm with Censored Data: A Case Study on Centrifugal Pumps in an Oil Refinery

This work is funded by National Funds through the FCT—Foundation for Science and Technology, I.P., within the scope of the project Ref. UIDB/05583/2020. Furthermore, we would like to thank the Research Centre in Digital Services (CISeD) and the Instituto Politécnico de Viseu for their support.Centrifugal pumps are widely employed in the oil refinery industry due to their efficiency and effectiveness in fluid transfer applications. The reliability of pumps plays a pivotal role in ensuring uninterrupted plant productivity and safe operations. Analysis of failure history data shows that bearings have been identified as critical components in oil refinery pump groups. Analyzing historical failure data for such systems is a complex task due to censored data and missing information. This paper addresses the complexity of estimating the Weibull distribution parameters using the maximum likelihood method under these conditions. The likelihood equation lacks an explicit analytical solution, necessitating numerical methods for resolution. The proposed approach presented in this article leverages the expectation maximization (EM) algorithm for estimating the Weibull distribution parameters in a real-world case study of a complex engineering system. The results demonstrate the superior performance of the EM algorithm with censored data, showcasing its ability to overcome the limitations of traditional methods and provide more accurate estimates for reliability metrics. This highlights the importance of obtaining results through these methodologies in the analysis of reliability and in facilitating more informed decision making in complex systemsinfo:eu-repo/semantics/publishedVersio

You are What you Eat (and Drink): Identifying Cultural Boundaries by Analyzing Food & Drink Habits in Foursquare

Food and drink are two of the most basic needs of human beings. However, as society evolved, food and drink became also a strong cultural aspect, being able to describe strong differences among people. Traditional methods used to analyze cross-cultural differences are mainly based on surveys and, for this reason, they are very difficult to represent a significant statistical sample at a global scale. In this paper, we propose a new methodology to identify cultural boundaries and similarities across populations at different scales based on the analysis of Foursquare check-ins. This approach might be useful not only for economic purposes, but also to support existing and novel marketing and social applications. Our methodology consists of the following steps. First, we map food and drink related check-ins extracted from Foursquare into users' cultural preferences. Second, we identify particular individual preferences, such as the taste for a certain type of food or drink, e.g., pizza or sake, as well as temporal habits, such as the time and day of the week when an individual goes to a restaurant or a bar. Third, we show how to analyze this information to assess the cultural distance between two countries, cities or even areas of a city. Fourth, we apply a simple clustering technique, using this cultural distance measure, to draw cultural boundaries across countries, cities and regions.Comment: 10 pages, 10 figures, 1 table. Proceedings of 8th AAAI Intl. Conf. on Weblogs and Social Media (ICWSM 2014

A systematic AQbD approach for optimization of the most influential experimental parameters on analysis of fish spoilage-related volatile amines

The volatile amines trimethylamine (TMA) and dimethylamine (DMA) could be used as important spoilage indices for seafood products, assisting in the determination of the rejection period. In the present study, a systematic analytical duality-by-design (AQbD) approach was used as a powerful strategy to optimize the most important experimental parameters of headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) conditions for the quantification of TMA and DMA in Sparus aurata. This optimization enabled the selection of the best points in the method operable design region for HS-SPME extraction (30 min; 35 ◦C; NaOH 15 M and NaCl 35%, w/v) and GC-MS analysis (80 ◦C; gradient 50 ◦C/min; flow rate 1 mL/min and splitless mode). The rejection day, estimated through the TMA concentration (>12 mg/100 g, at days 9–10), was compared with sensory (quality index method: day 7–8), physical (Torrymeter: day 8–9), and microbial (day 9–10) analysis, corroborating the suitability of the proposed approach for estimating the period for which they will retain an acceptable level of eating quality from a safety and sensory perspective.info:eu-repo/semantics/publishedVersio

Can We Assess the Success of Surgery for Degenerative Spinal Diseases Using Patients' Recall of Their Preoperative Status?

Background: Patients' recall of their preoperative status is seldom used to assess surgical outcomes because of concerns of inaccuracy and bias. Objective: The present study aims to measure the significance of this recall bias and its repercussion on patients' recollection of their preoperative status. Methods: Patients submitted to surgery due to degenerative spine diseases during the period of one year (n=198) were included in this study. EQ-5D (including EQ VAS), COMI Neck (including Neck Pain and Shoulder/Arm Pain NRS), COMI Back (including Back Pain and Buttock/Leg Pain NRS), NDI and ODI were completed preoperatively. One year after surgery, patients were asked to complete 2 sets of the same questionnaires, one regarding their postoperative status and the other one regarding their recall of the preoperative status. Results: There was poor to moderate agreement between recalled and collected preoperative scores for all PROMs. Patients' recollection of their preoperative status was accurate for patients who underwent cervical spine surgery, but not after lumbar spine surgery. Patients satisfied with the outcome after lumbar spine surgery recalled significantly worse scores compared to the preoperatively collected. Conclusions: Using patients' recall of their preoperative status may lead to an overestimation of the surgery effectiveness, particularly for lumbar spine surgery. The self-assessed surgery effectiveness interferes with the recollection of the baseline status.info:eu-repo/semantics/publishedVersio

Novas Fronteiras no Prognóstico

A pancreatite aguda é um processo inflamatório do pâncreas com variável envolvimento dos tecidos pancreático, peripancreáticos e órgãos à distância. Em 80% dos casos a pancreatite aguda é leve, com edema intersticial e com recuperação, geralmente dentro da primeira semana. A pancreatite necrotizante, que pode ocorrer entre 15 a 20% dos doentes, é caracterizada por necrose, envolvendo o pâncreas e os tecidos peripancreáticos. Quando complicada por infeção está associada a uma alta morbimortalidade e a elevados encargos económicos. Foi demonstrado, em vários estudos, o papel do stresse oxidativo na fisiopatologia da pancreatite aguda, particularmente na patogénese e na progressão deste processo inflamatório. No entanto, não está claro se as espécies reativas de oxigénio atuam como mediadores ou se iniciam a complexa cascata de eventos que leva à pancreatite aguda. O papel exato do stresse oxidativo no desenvolvimento desta condição patológica permanece assim por esclarecer. A identificação precoce de doentes que irão desenvolver pancreatite aguda grave é de extrema importância, uma vez que vai permitir uma monitorização mais apertada, uma terapia de suporte individualizada e a prevenção das complicações associadas. O objetivo desta dissertação foi aprofundar o conhecimento da fisiopatologia da pancreatite aguda no contexto de doentes com etiologia litiásica, nomeadamente na sua patogénese e na progressão do processo inflamatório, através da avaliação do stresse oxidativo e na identificação de novos biomarcadores de prognóstico, recorrendo-se ao estudo do perfil metabolómico. Neste sentido, foi realizado um estudo em modelo animal e um estudo clínico numa amostra de doentes, de modo a identificar possíveis biomarcadores de prognóstico da pancreatite aguda de etiologia litiásica. O estudo experimental realizado no rato, como modelo animal, consistiu na indução da pancreatite aguda em modelos cirúrgicos, que mimetizam a etiologia litiásica e num modelo não cirúrgico, modelo da hiperestimulação com análogo da colecistoquinina, a ceruleína. Foi proposto um score de gravidade da pancreatite aguda com recurso a parâmetros histológicos: edema, necrose, infiltrado inflamatório, hemorragia e vacuolização e que permitiu a classificação da pancreatite aguda em ausente, ligeira, moderada e grave. Quando se correlacionou este score com a procalcitonina, verificou-se uma correlação muito forte, indicando que a gravidade do score reflete o processo inflamatório pancreático. Verificou-se que o stresse oxidativo assumiu um papel na fase precoce do processo inflamatório pancreático, com a elevação dos níveis das espécies reativas de oxigénio, uma diminuição das defesas antioxidantes e disfunção mitocondrial nos animais com pancreatite aguda e nas suas formas mais graves. No estudo clínico constatou-se que, na amostra constituída por doentes com pancreatite aguda litiásica, na admissão, o azoto ureico, os neutrófilos e os leucócitos foram os melhores marcadores de gravidade, às 48 horas, a hepcidina, a razão neutrófilos/linfócitos e o índex de resposta inflamatória sistémica foram os melhores biomarcadores de prognóstico. Quando se avaliou o stresse oxidativo, na admissão dos doentes, observou-se uma elevação dos níveis das espécies reativas de oxigénio, uma diminuição das defesas antioxidantes e disfunção mitocondrial, principalmente naqueles com pancreatite aguda grave. Estes achados evidenciam o papel do stresse oxidativo como mediador, desde a fase inicial da pancreatite aguda litiásica, e como eventual marcador de prognóstico. Foi, também na admissão dos doentes, estudado o perfil metabolómico que permitiu identificar, como eventuais biomarcadores de prognóstico da pancreatite aguda litiásica grave, a treonina, a fenilalanina e os lípidos. Este estudo translacional permitiu identificar novos biomarcadores de prognóstico e contribuir para uma melhor compreensão do processo fisiopatológico da pancreatite aguda litiásica.Acute pancreatitis is an inflammatory process of the pancreas with variable involvement of the pancreatic, peripancreatic tissues and distant organs. In 80% of cases, acute pancreatitis is mild, with interstitial oedema and recovery, usually within the first week. Necrotising pancreatitis, which may occur in 15-20% of patients, is characterised by necrosis involving the pancreas and peripancreatic tissues. When complicated by infection, it is associated with high morbidity and mortality and a high economic burden. The role of oxidative stress in the pathophysiology of acute pancreatitis has been demonstrated in several studies, particularly in the pathogenesis and progression of this inflammatory process. However, it is unclear whether reactive oxygen species act as mediators or initiate the complex cascade of events leading to acute pancreatitis. The exact role of oxidative stress in the development of this pathological condition thus remains unclear. Early identification of patients who will develop severe acute pancreatitis is of utmost importance, as it will allow closer monitoring, individualised supportive therapy and the prevention of associated complications. This dissertation aims to deepen the knowledge of the pathophysiology of acute pancreatitis in patients with biliary etiology, particularly in its pathogenesis and in the progression of the inflammatory process, through the assessment of oxidative stress and in the identification of new prognostic biomarkers, using the study of the metabolomic profile. In this sense, a study in an animal model and a clinical study in a sample of patients was performed to identify possible prognostic biomarkers of biliary acute pancreatitis. The experimental in the rat, as an animal model, consisted in induction of acute pancreatitis in surgical models, mimicking the lithiasis aetiology and in a non-surgical model, hyperstimulation model with cholecystokinin analogue, cerulein. A score of severity of acute pancreatitis was proposed using histological parameters: oedema, necrosis, inflammatory infiltrate, haemorrhage and vacuolization, which allowed the classification of acute pancreatitis into absent, mild, moderate and severe. When this score was correlated with procalcitonin, a very strong correlation was found, indicating that the severity of the score reflects the pancreatic inflammatory process. Oxidative stress was found to play a role in the early stage of the pancreatic inflammatory process, with increased levels of reactive species, decreased antioxidant defences and mitochondrial dysfunction in animals with acute pancreatitis and in its more severe forms. In the clinical study, we found that in the sample of patients with biliary acute pancreatitis, on admission, blood urea nitrogen, neutrophils and leucocytes were the best markers of severity. At 48 hours hepcidin, neutrophil-lymphocyte ratio and systemic inflammatory response index were the best biomarkers of prognosis. When oxidative stress was assessed at patient admission, an elevation in reactive oxygen species levels, decreased antioxidant defences, and mitochondrial dysfunction was observed, mainly in those with severe acute pancreatitis. These findings highlight the role of oxidative stress as a mediator, from the initial phase of biliary acute pancreatitis and as a possible prognostic marker. The metabolomic profile of patients was also studied at admission, allowing the identification of threonine, phenylalanine and lipids as possible prognostic biomarkers of severe biliary acute pancreatitis. This translational study allowed us to identify new prognostic biomarkers and better understand the pathophysiological process of biliary acute pancreatitis

External approach to bilaterally septated maxillary sinuses: a case report

Communication abstract: Proceedings of the 5th International Congress of CiiEM - Reducing inequalities in Health and Society, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from June 16th to 18th, 2021.This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.The careful planning of a sinus lift procedure is the key to avoiding surgical complications. In this clinical case, a female patient, 59 years old and totally edentulous in the maxilla, was referred to Egas Moniz’s Dental Clinic Implantology consultation with indication for bilateral external sinus lift of the maxillary sinuses prior to implant placement. Both orthopantomography and cone-beam computed tomography were used to show the anatomy of the maxillary sinuses, which presented multiple sinus septa. A multiple anterolateral window approach was applied in order to avoid perforation of the Schneiderian membrane while accessing it.info:eu-repo/semantics/publishedVersio

Improved approach based on MALDI-TOF MS for establishment of the fish mucus protein pattern for geographic discrimination of Sparus aurata

Food fraud is still a recurrent practice throughout food supply chains. In the case of seafood, misidentification of species and products repackaging constitute the most common frauds. Therefore, the development of appropriate analytical approaches to be used against food fraud is necessary. The present study goal is to explore for the first time, the possibility to differentiate between Sparus aurata from two different mariculture farms located in Madeira Island (Caniçal and Ribeira Brava), using the mass fingerprint of fish mucus obtained from MALDI-TOF MS and analyzed using Mass-UP software for multivariate statistical analysis and biomarker identification. It was possible to establish, from the mucus protein fraction, a set of potential biomarkers for each location in a total of 35 peaks, being 17 peaks specific to Caniçal located farm and 18 to Ribeira Brava. The proposed analytical approach revealed a useful strategy providing accurate and fast results for fish geographical origin discrimination.info:eu-repo/semantics/publishedVersio

An anti-inflammatory and low fermentable oligo, di, and monosaccharides and polyols diet improved patient reported outcomes in fibromyalgia: A randomized controlled trial

Background: Fibromyalgia (FM) has been associated with dysbiosis and low-grade inflammation. Studies have reported that diet influences clinical features in FM. Objective: To evaluate the effect of an anti-inflammatory and low fermentable oligo, di, and monosaccharides and polyols (FODMAP) diet on clinical outcomes of patients with FM. Methods: This two arms Randomized Controlled Trial (NCT04007705) included 46 female patients with FM. The intervention group (n = 22) adopted an anti-inflammatory diet for 3 months, excluding gluten, dairy, added sugar, and ultra-processed foods, along with a low FODMAPs diet in the first month. The control group (n = 24) followed general healthy eating recommendations. Both diets were applied by a certified dietitian. Before and after the intervention, participants were assessed regarding pain, fatigue, gastrointestinal symptoms, quality of sleep, and quality of life, through the Revised Fibromyalgia Impact Questionnaire (FIQR), Visual Analogue Pain Scale (VAS), Visual Analog Scale from gastrointestinal symptoms (VAS GI), Brief Pain Inventory (BPI), Pittsburg Sleep Quality Index (PSQI), Fatigue Severity Survey (FSS), and The Short Form Health Survey (SF-36). A blood sample was collected and high-sensitive C-Reactive Protein and Erythrocyte Sedimentation Rate were quantified. Paired Samples t-test/Wilcoxon and independent samples t-test/Mann-Whitney were used to compare variables between groups. Results: After intervention, there was an improvement in intervention group scores of FIQR (p = 0.001), VAS (p = 0.002), BPI (p = 0.011), FSS (p = 0.042), VAS_GI (p = 0.002), PSQI (p = 0.048), and SF36 (p = 0.045) compared to control group. Inflammatory biomarkers (hs-CRP, ESR) did not change in both groups. The intervention was beneficial in the intervention group, regardless of age, disease duration, body mass index variation, and body fat change between baseline and post-intervention. Conclusion: An anti-inflammatory and low-FODMAP diet improved clinical features in patients with FM and may be useful as a complement to pharmacological therapy

O afastamento do lar do suposto agressor nos casos de violência doméstica pela autoridade policial

The aim in this study is to analyze the provision brought by the Law n. 13.827/19 that allowed the removal of the supposed aggressor from home in cases of domestic violence by police authority, in contrast with the principles of the home inviolability, forbiddance of insufficient protection, separation of powers and judicial reserve. The research was realized by the deductive method and through doctrinal and jurisprudential research. The subject holds relevance and topicality, searching for efficient mechanisms to repress the domestic and family violence against a woman that is still rooted in society and stills persists nowadays. The new hypothesis for the removal from home brought by the law aims to maximize women rights, ensuring their security and physical integrity, providing more effective protection under the circumstances in this specific case, with a view that the state-judge is not present all the time and in all the situations. On the other side, the issue apparently comes in conflict with others provisions of the legal system, such as the separations of powers and the reservations of jurisdictions. Either way, throughout the study developed it was concluded that the removal from home of supposed aggressor in case of domestic and family violence by the police authority shows itself reasonable facing the marks brought by law, adopting the measure in a exceptional and subsidiary way.Objetiva-se com o presente artigo analisar as disposições trazidas pela Lei n. 13.827/19 que possibilitou o afastamento do lar do suposto agressor nos casos de violência doméstica pela Autoridade Policial, contrastando com os princípios da inviolabilidade do domicílio, da vedação à proteção insuficiente, da separação dos poderes e da reserva de jurisdição. A pesquisa foi realizada através do método dedutivo e por meio de uma pesquisa doutrinária e jurisprudencial. O tema guarda grande pertinência e atualidade, diante da busca de mecanismos eficientes para coibir a violência doméstica e familiar contra a mulher enraizada na sociedade que perdura até os dias atuais. A nova hipótese de afastamento do lar trazida pela lei busca potencializar os direitos das mulheres, assegurando especialmente a sua segurança e integridade física, fornecendo uma proteção mais adequada diante das circunstâncias do caso concreto, tendo em vista que o Estado-juiz não se mostra presente o tempo todo e em todas as situações. Lado outro, a problemática aparentemente conflita com outras disposições do ordenamento jurídico, como a separação dos poderes e a reserva de jurisdição. De todo modo, ao longo do estudo desenvolvido conclui-se que o afastamento do lar do suposto agressor nos casos de violência doméstica e familiar pela autoridade policial se mostra razoável diante das balizas trazidas pela lei, adotando-se a medida de maneira excepcional e subsidiária