Browsing by Author "Pinto, Iola"
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- An enhanced capacity model based on network measurements for a multi-service 3G systemPublication . Parracho, Diogo; Duarte, David; Pinto, Iola; Vieira, PedroWith the ongoing growth on mobile networks utilization, new challenges come up in order to achieve a better efficient resource network management. The purpose of this paper is to present a multi-service platform based on admission curves for Third Generation (3G) and beyond mobile networks, depending on some cell characteristics, which are calculated based on real measurements. The model considers admission curves based on the Multidimensional Erlang-B model, which defines the maximum limit of resource utilization for a given Quality of Service (QoS), and will manage traffic between several services. The proposed method takes different specific constraints for each traffic environment based on network performance. To estimate the cell characteristics, for Voice and Packet Switched (PS) Release 99 (R99) services, a method is proposed, based on the Multiple Linear Regression model and dependent on Key Performance Indicators (KPI) taken from a live mobile network. For High Speed Downlink Packet Access (HSDPA) service, a different approach is set since there is a well defined time to transmit data (Transmission Time Interval (TTI)) along with other important features, like Channel Quality Indicator (CQI) and Block Error Rate (BLER), to be considered.
- An improved capacity model based on radio measurements for a 4G and beyond wireless networkPublication . Parracho, Diogo; Duarte, David; Pinto, Iola; Vieira, PedroThe mobile networks utilization is increasingly high, which implies a efficient resource network management coupled with a realistic capacity model. The aim of this paper is to present a capacity platform for Fourth Generation (4G) mobile networks, based on real measurements. The core of the proposed method is the deployment of a Multiple Linear Regression (MLR) model, based on propagation conditions, channel quality and delays for a specific cell. Information about how to locate the resource bottleneck and the related handling suggestions are provided. This approach outputs the maximum cell throughput at the busy hour, under realistic conditions. The method was developed using real data extracted from a live mobile network.
- An interactive dashboard for statistical analysis of intensive care unit COVID-19 dataPublication . Dias, Rúben; Ferreira, Artur; Pinto, Iola; Brás-Geraldes, Carlos; Von Rekowski, Cristiana; Bento, LuísCOVID-19 caused a pandemic, due to its ease of transmission and high number of infections. The evolution of the pandemic and its consequences for the mortality and morbidity of populations, especially the elderly, generated several scientific studies and many research projects. Among them, we have the Predictive Models of COVID-19 Outcomes for Higher Risk Patients Towards a Precision Medicine (PREMO) research project. For such a project with many data records, it is necessary to provide a smooth graphical analysis to extract value from it. Methods: In this paper, we present the development of a full-stack Web application for the PREMO project, consisting of a dashboard providing statistical analysis, data visualization, data import, and data export. The main aspects of the application are described, as well as the diverse types of graphical representations and the possibility to use filters to extract relevant information for clinical practice. Results: The application, accessible through a browser, provides an interactive visualization of data from patients admitted to the intensive care unit (ICU), throughout the six waves of COVID-19 in two hospitals in Lisbon, Portugal. The analysis can be isolated per wave or can be seen in an aggregated view, allowing clinicians to create many views of the data and to study the behavior and consequences of different waves. For instance, the experimental results show clearly the effect of vaccination as well as the changes on the most relevant clinical parameters on each wave. Conclusions: The dashboard allows clinicians to analyze many variables of each of the six waves as well as aggregated data for all the waves. The application allows the user to extract information and scientific knowledge about COVID-19’s evolution, yielding insights for this pandemic and for future pandemics.
- Complete pathological response (pCR) in gastroesophageal cancer: Correlation with metabolic responsePublication . Cabral, Francisco; Cruz, A.; Casaca, R.; Monteiro, C.; Ramos, P.; Pedro, C.; Brandão, F.; Fonseca, R.; Ratão, P.; Saldado, L.; Pinto, Iola; Abecasis, N.Purpose. - Neoadjuvant chemoradiotherapy (nCRT) followed by surgery in patients with resectable esophageal or esophagogastric junctional (GEJ) (Siewert I) cancer is associated with long term overall survival benefits. Up to one third of all patients submitted to nCRT present pathological complete response (pCR). F-18-fluorodeoxyglucose positron emission tomography with CT (F-18-FDG PET-CT) is an important tool for assessing treatment response. Purpose was to assess retrospectively the power of F-18-FDG PET-CT in predicting pCR to evaluate the feasibility of a "watch and wait" approach. Patients and methods. - Retrospective analysis of a prospective database with esophageal or GEJ submitted to pre-operative chemoradiation. Pre and pos treatment F-18-FDG PET-CT were reviewed and classified using visual assessment and PERCIST criteria and the values of maximum standard uptake value were also recorded. Patients were classified as pCR or non-PCR. F-18-FDG PET-CT and pathological findings were compared against each other. Results. - Forty-three patients were included. The median age was 67 years and 90.7% were male. All patients underwent preoperative CRT and were evaluated with F-18-FDG PET-CT pre and post treatment. Transthoracic surgery was performed in all patients. Histological type was adenocarcinoma in 37% and squamous cell carcinoma in 58%. pCR was achieved in 56% of cases. Visual assessment of F-18-FDG PET-CT showed overall sensitivity 57.9%, specificity 62.5% and PERCIST criteria had 100% sensibility and 16.7% specificity. Conclusions. - F-18-FDG PET-CT is not an ideal predictor of pCR but if we use the PERCIST criteria we will have a high sensitivity and negative predictive value, avoiding false negative scans. (C) 2020 Societe francaise de radiotherapie oncologique (SFRO).
- Detection and adsorption of Triclosan on sensors based on PAH/PVS thin-filmsPublication . Pereira-da-Silva, J.; Zagalo, P. M..; Magro, Cátia; Pinto, Iola; Ribeiro, P. A.; Raposo, MariaGiven the vital role of water in life it is paramount to thrive and succeed in areas that look to clean and prevent further contamination in water bodies. Triclosan (TCS) is present in most of our day-to-day products and if left unchecked it can lead to long-term significant problems due to its many inauspicious effects in both human and animal health. Thus arose the need to develop sensors to detect and possibly remove TCS for aqueous solutions. This work was rooted on this premise and sensors based on LbL polyectrolyte thin-films were developed, such as poly(allylamine hydrochloride) (PAH) and poly(vinylsulfonic acid, sodium salt) (PVS), namely (PAH/PVS)(10) and (PAH/PVS)/PAH(10). The goal of this work was to analyze the amount of TCS adsorbed onto reused (PAH/PVS)(10) and (PAH/PVS)/PAH(10) LbL thin-films when immersed in TCS aqueous solutions with decreasing pH. It was demonstrated that sensors with an outer layer of PAH led to a significantly better TCS molecules adsorption (removal). Additionally, sensors composed of (PAH/PVS)(10) presented higher sensibility in discriminating TCS solutions with concentrations between 10(-5) M and 10(-8) M, using impedance spectroscopy.
- Higher mineralized bone volume is associated with a lower plain X-Ray vascular calcification score in hemodialysis patientsPublication . Adragao, Teresa; Ferreira, Anibal; Frazão, João; Papoila, Ana Luisa; Pinto, Iola; Monier-Faugere, Marie-Claude; Malluche, Hartmut H.Background and objectives In dialysis patients, there is an increasing evidence that altered bone metabolism is associated with cardiovascular calcifications. The main objective of this study was to analyse, in hemodialysis patients, the relationships between bone turnover, mineralization and volume, evaluated in bone biopsies, with a plain X-ray vascular calcification score. Design, setting, participants and measurements In a cross-sectional study, bone biopsies and evaluation of vascular calcifications were performed in fifty hemodialysis patients. Cancellous bone volume, mineralized bone volume, osteoid volume, activation frequency, bone formation rate/bone surface, osteoid thickness and mineralization lag time were determined by histomorphometry. Vascular calcifications were assessed by the simple vascular calcification score (SVCS) in plain X-Ray of pelvis and hands and, for comparison, by the Agatston score in Multi-Slice Computed Tomography (MSCT). Results SVCS >= 3 was present in 20 patients (40%). Low and high bone turnover were present in 54% and 38% of patients, respectively. Low bone volume was present in 20% of patients. In multivariable analysis, higher age (p = 0.015) and longer hemodialysis duration (p = 0.017) were associated with SVCS >= 3. Contrary to cancellous bone volume, the addition to this model of mineralized bone volume (OR = 0.863; 95% CI: 0.766, 0.971; p = 0.015), improved the performance of the model. For each increase of 1% in mineralized bone volume there was a 13.7% decrease in the odds of having SVCS >= 3 (p = 0.015). An Agatston score> 400 was observed in 80% of the patients with a SVCS >= 3 versus 4% of patients with a SVCS<3, (p<0.001). Conclusion Higher mineralized bone volume was associated with a lower plain X-ray vascular calcification. This study corroborates the hypothesis of the existence of a link between bone and vessel and reinforces the clinical utility of this simple and inexpensive vascular calcification score in dialysis patients.
- Impact of perioperative chemotherapy on postoperative morbidity after gastrectomy for gastric cancerPublication . Cabral, Francisco; Ramos, Paulo; Monteiro, Cecília; Casaca, Rui; Pinto, Iola; Abecasis, NunoIntroduction: The use of perioperative chemotherapy (CT) in patients with advanced gastric carcinoma increases their overall survival. This therapy may also increase the number of patients with R0 resection. Potential drawbacks of this therapy, besides its toxicity, include increased surgical morbidity. Methods: We retrospectively evaluated the records of patients undergoing gastrectomy with curative intent, for carcinoma, at our institution between January 2009 and August 2018. They were divided into two groups: direct surgery (SURG) and perioperative CT (CHEMO). Patients with other neoadjuvant therapies and cardia Siewert I and II carcinomas were excluded. The primary objective was to evaluate the impact of perioperative CT on surgical morbidity. As secondary objectives, resection radicality and total lymph node count were compared between the two groups. Results: A total of 307 patients (97 direct surgery and 210 perioperative CT) were evaluated. Median age was 67 years old. The overall major surgical morbidity (Clavien-Dindo 3-5) was 10.6% in the CHEMO group and 12.4 in the SURG group (p = 0.643). There was no statistically significant difference between the surgical radicality (R0 98% in the SURG group vs 97.5% CHEMO group (p = 0.865). There was an increase in the total number of lymph nodes retrieved in the specimen in the CHEMO group (25 vs 22, p = 0.001), a difference that was not maintained in the subgroup analysis as a function of the surgery performed. Conclusions: Perioperative CT in gastric carcinoma does not increase surgical morbidity, surgical radicality and total lymph node count. (C) 2020 AEC. Published by Elsevier Espana, S.L.U. All rights reserved.
- Improving indoor air quality in a higher-education institution through biophilic solutionsPublication . Idália da Gomes, Maria; Joanaz De Melo, Ana Maria Garcia Henriques Barreiros; Pinto, Iola; Rodrigues, AlexandraSchools are vital infrastructures where students acquire essential skills and foster social values. Indoor air quality (IAQ) is of paramount importance in schools, given that students spend a considerable amount of time indoors. This study examines the influence of a natural green structure (NGS) on IAQ in an Eco-Campus classroom. The IAQ of a classroom with an NGS was compared to that of an adjacent classroom without an NGS. The thermal conditions were monitored, including air temperature (T) and relative humidity (RH), as well as indoor pollutants, including carbon dioxide (CO2), volatile organic compounds (VOCs), and particulate matter (PM2.5 and PM10). The findings indicated a substantial improvement in indoor air quality in the classroom where the green structure was installed. This study lends support to the incorporation of biophilic solutions as sustainable approaches to fostering healthier learning environments, which in turn can lead to improvements in student performance and well-being.
- Laboratory biomarkers associated to death in the first three COVID-19 waves in PortugalPublication . Von Rekowski, Cristiana; Fonseca, Tiago; Calado, Cecília; Bento, Luís; Pinto, Iola; Araújo, RúbenBesides the pandemic being over, new SARS-CoV-2 lineages, and sub-lineages, still pose risks to global health. Thus, in this preliminary study, to better understand the characteristics of COVID-19 patients and the effect of certain hematologic biomarkers on their outcome, we analyzed data from 337 patients admitted to the ICU of a single-center hospital in Lisbon, Portugal, in the first three waves of the pandemic. Most patients belonged to the second (40.4%) and third (41.2%) waves. The ones from the first wave were significantly older and relied more on respiratory techniques like invasive mechanic ventilation and extracorporeal membrane oxygenation. There were no significant differences between waves regarding mortality in the ICU. In general, non-survivors had worse laboratory results. Biomarkers significantly associated with death changed depending on the waves. Increased high-sensitivity cardiac troponin I results, and lower eosinophil counts were associated to death in all waves. In the second and third waves, the international normalized ratio, lymphocyte counts, and neutrophil counts were also associated to mortality. A higher risk of death was linked to increased myoglobin results in the first two waves, as well as increased creatine kinase results, and lower platelet counts in the third wave.
- Mapping atmospheric pollutants emissions in European countriesPublication . Martins, Ana Alexandra; Cardoso, Margarida G. M. S.; Pinto, IolaIn this paper we present a methodology which enables the graphical representation, in a bi-dimensional Euclidean space, of atmospheric pollutants emissions in European countries. This approach relies on the use of Multidimensional Unfolding (MDU), an exploratory multivariate data analysis technique. This technique illustrates both the relationships between the emitted gases and the gases and their geographical origins. The main contribution of this work concerns the evaluation of MDU solutions. We use simulated data to define thresholds for the model fitting measures, allowing the MDU output quality evaluation. The quality assessment of the model adjustment is thus carried out as a step before interpretation of the gas types and geographical origins results. The MDU maps analysis generates useful insights, with an immediate substantive result and enables the formulation of hypotheses for further analysis and modeling.