Federated Learning for Early Dropout Prediction on Healthy Ageing Applications

The provision of social care applications is crucial for elderly people to improve their quality of life and enables operators to provide early interventions. Accurate predictions of user dropouts in healthy ageing applications are essential since they are directly related to individual health statuses. Machine Learning (ML) algorithms have enabled highly accurate predictions, outperforming traditional statistical methods that struggle to cope with individual patterns. However, ML requires a substantial amount of data for training, which is challenging due to the presence of personal identifiable information (PII) and the fragmentation posed by regulations. In this paper, we present a federated machine learning (FML) approach that minimizes privacy concerns and enables distributed training, without transferring individual data. We employ collaborative training by considering individuals and organizations under FML, which models both cross-device and cross-silo learning scenarios. Our approach is evaluated on a real-world dataset with non-independent and identically distributed (non-iid) data among clients, class imbalance and label ambiguity. Our results show that data selection and class imbalance handling techniques significantly improve the predictive accuracy of models trained under FML, demonstrating comparable or superior predictive performance than traditional ML models

Deep Learning for Energy Time-Series Analysis and Forecasting

Energy time-series analysis describes the process of analyzing past energy observations and possibly external factors so as to predict the future. Different tasks are involved in the general field of energy time-series analysis and forecasting, with electric load demand forecasting, personalized energy consumption forecasting, as well as renewable energy generation forecasting being among the most common ones. Following the exceptional performance of Deep Learning (DL) in a broad area of vision tasks, DL models have successfully been utilized in time-series forecasting tasks. This paper aims to provide insight into various DL methods geared towards improving the performance in energy time-series forecasting tasks, with special emphasis in Greek Energy Market, and equip the reader with the necessary knowledge to apply these methods in practice.Comment: 13 papges, 4 figure

The importance of colonization pressure in multiresistant Acinetobacter baumannii acquisition in a Greek intensive care unit

Introduction: We investigated the role of colonization pressure on multiresistant Acinetobacter baumannii acquisition and defined patient-related predictors for carriage at admission and acquisition during hospitalization in intensive care unit (ICU) patients. Methods: This was a 12-month, prospective, cohort study of all patients admitted to a single ICU of a tertiary hospital. Screening samples were collected at ICU admission to identify imported carriers, and weekly during hospitalization to identify acquisition. Colonization pressure (carriers’ patient-days × 100/all patients’ patient-days) and the absolute number of carriers were calculated weekly, and the statistical correlation between these parameters and acquisition was explored. Multivariable analysis was performed to identify predictors for A. baumannii carriage at admission and acquisition during hospitalization. A. baumannii isolates were genotyped by repetitive-extragenic-palindromic polymerase chain reaction (PCR; rep-PCR). Results: At ICU admission, 284 patients were screened for carriage. A. baumannii was imported in 16 patients (5.6%), and acquisition occurred in 32 patients (15.7%). Acquisition was significantly correlated to weekly colonization pressure (correlation coefficient, 0.379; P = 0.004) and to the number of carriers per week (correlation coefficient, 0.499;

The importance of colonization pressure in multiresistant Acinetobacter baumannii acquisition in a Greek intensive care unit

INTRODUCTION: We investigated the role of colonization pressure on multiresistant Acinetobacter baumannii acquisition and defined patient-related predictors for carriage at admission and acquisition during hospitalization in intensive care unit (ICU) patients. METHODS: This was a 12-month, prospective, cohort study of all patients admitted to a single ICU of a tertiary hospital. Screening samples were collected at ICU admission to identify imported carriers, and weekly during hospitalization to identify acquisition. Colonization pressure (carriers' patient-days × 100/all patients' patient-days) and the absolute number of carriers were calculated weekly, and the statistical correlation between these parameters and acquisition was explored. Multivariable analysis was performed to identify predictors for A. baumannii carriage at admission and acquisition during hospitalization. A. baumannii isolates were genotyped by repetitive-extragenic-palindromic polymerase chain reaction (PCR; rep-PCR). RESULTS: At ICU admission, 284 patients were screened for carriage. A. baumannii was imported in 16 patients (5.6%), and acquisition occurred in 32 patients (15.7%). Acquisition was significantly correlated to weekly colonization pressure (correlation coefficient, 0.379; P = 0.004) and to the number of carriers per week (correlation coefficient, 0.499; P <0.001). More than one carrier per week significantly increased acquisition risk (two to three carriers, odds ratio (OR), 12.66; P = 0.028; more than four carriers, OR, 25.33; P = 0.004). Predictors of carriage at admission were infection at admission (OR, 11.03; confidence interval (CI), 3.56 to 34.18; P < 0.01) and hospitalization days before ICU (OR, 1.09; CI, 1.01 to 1.16; P = 0.02). Predictors of acquisition were a medical reason for ICU admission (OR, 5.11; CI, 1.31 to 19.93; P = 0.02), duration of antibiotic administration in the unit (OR, 1.24; CI, 1.12 to 1.38; P < 0.001), and duration of mechanical ventilation (OR, 1.08; CI, 1.04 to 1.13; P = 0.001). All strains were multiresistant. Rep-PCR analysis showed one dominant cluster. CONCLUSIONS: Acquisition of multiresistant A. baumannii in ICU patients is strongly correlated to colonization pressure. High levels of colonization pressure and more than two carriers per week independently increase acquisition risk. Patient-related factors, such as infection at admission and long hospitalization before the ICU, can identify imported A. baumannii carriers. Medical patients with extended administration of antibiotics and long duration of mechanical ventilation in the ICU were the most vulnerable to acquisition

Liquefied natural gas for civil aviation

The growth in air transport and the ambitious targets in emission reductions set by advisory agencies are some of the driving factors behind research towards new fuels for aviation. Liquefied Natural Gas (LNG) could be both environmentally and economically beneficial. However, its implementation in aviation has technical challenges that needs to be quantified. This paper assesses the application of LNG in civil aviation using an integrated simulation and design framework, including Cranfield University’s aircraft performance tool, Orion, and engine performance simulation tool Turbomatch, integrated with an LNG tank sizing module and an aircraft weight estimation module. Changes in tank design, natural gas composition, airframe changes, and propulsion system performance are assessed. The performance benefits are quantified against a Boeing 737–800 aircraft. Overall, LNG conversion leads to a slightly heavier aircraft in terms of the operating weight empty (OWE) and maximum take-off weight (MTOW). The converted aircraft has a slightly reduced range compared to the conventional aircraft when the maximum payload is considered. Compared to a conventional aircraft, the results indicate that although the energy consumption is increased in the case of LNG, the mission fuel mass is decreased and CO2 emissions are reduced by more than 15%. These benefits come with a significant reduction in fuel cost per passenger, highlighting the potential benefits of adopting LNG for aviatio

Foxp3 Expression in Liver Correlates with the Degree but Not the Cause of Inflammation

Patients with chronic viral hepatitis display increased expression of Foxp3 in liver, suggesting that Tregs expansion contributes to persistent infection. The purpose of this study was to elucidate whether the expression of Foxp3 relates not to the viral infection but to the resulting liver inflammation. Liver biopsies obtained from 69 individuals (26 chronic HBV hepatitis, 14 chronic HCV hepatitis, 11 nonalcoholic fatty liver disease, 8 autoimmune diseases, 2 methotrexate-related toxicity, and 8 controls) were examined, by qRT-PCR, for the mRNA expression of Foxp3, IL-10, TGF-β1, Fas, FasL, TRAIL, caspase-3, TNF-α, IFN-γ, and IL-1β. Significant increase of Foxp3 was observed in all disease groups compared to controls, which was positively correlated with the intensity of inflammation. The expression of the apoptosis mediators Fas, FasL, and TRAIL, but not of IL-10 and TGF-β1, was also significantly elevated. Our findings indicate that, independently of the initial inducer, liver inflammation is correlated with elevated expression of apoptosis mediators and is followed by local Treg accumulation. Further research towards the elucidation of the underlying casual relationships is required, in order to clarify whether our results signify the existence of a uniform Treg-mediated regulatory mechanism of apoptosis-induced inflammation

Evaluation of young smokers and non-smokers with Electrogustometry and Contact Endoscopy

<p>Abstract</p> <p>Background</p> <p>Smoking is the cause of inducing changes in taste functionality under conditions of chronic exposure. The objective of this study was to evaluate taste sensitivity in young smokers and non-smokers and identify any differences in the shape, density and vascularisation of the fungiform papillae (fPap) of their tongue.</p> <p>Methods</p> <p>Sixty-two male subjects who served in the Greek military forces were randomly chosen for this study. Thirty-four were non-smokers and 28 smokers. Smokers were chosen on the basis of their habit to hold the cigarette at the centre of their lips. Taste thresholds were measured with Electrogustometry (EGM). The morphology and density of the fungiform papillae (fPap) at the tip of the tongue were examined with Contact Endoscopy (CE).</p> <p>Results</p> <p>There was found statistically important difference (<it>p </it>< 0.05) between the taste thresholds of the two groups although not all smokers presented with elevated taste thresholds: Six of them (21%) had taste thresholds similar to those of non-smokers. Differences concerning the shape and the vessels of the fungiform papillae between the groups were also detected. Fewer and flatter fPap were found in 22 smokers (79%).</p> <p>Conclusion</p> <p>The majority of smokers shown elevated taste thresholds in comparison to non-smokers. Smoking is an important factor which can lead to decreased taste sensitivity. The combination of methods, such as EGM and CE, can provide useful information about the vascularisation of taste buds and their functional ability.</p

Solar Energy Harnessing Technologies towards De-Carbonization: A Systematic Review of Processes and Systems

Solar energy, derived from the inexhaustible energy of the sun, has emerged as a promising solution to mitigate the environmental challenges posed by fossil fuel consumption and global climate change. This work explores the underlying principles of solar energy exploitation, focusing on energy collection technologies as the primary means of solar energy conversion. The physics of the state-of-the-art mechanisms, the photovoltaic effect, and the advancements that have driven the transformation of solar energy into a viable and sustainable alternative energy source are also examined. Through a comprehensive review of relevant literature and pioneering research, this study highlights the immense potential of solar energy and its role in shaping a cleaner, greener future. Towards de-carbonization, the various exploitation technologies are divided into direct and indirect in order to optimize resource utilization. Accounting for the most important advantages presented, solar-based utilization processes are perhaps the only ones that provide access to energy for all to satisfy their vital needs. As nations continue to embrace solar energy and invest in its development, we move closer to achieving a more sustainable and environmentally friendly world for generations to come

Pulsed-Supplied Water Electrolysis via Two-Switch Converter for PV Capacity Firming

Hydrogen constitutes the only carbon-free fuel that can be used for energy conversion, producing water as the only by-product. With water being one of the most abundant and inexhaustible raw materials in the world, and the required electricity input being provided by renewable resources, the produced hydrogen via water electrolysis constitutes a green pathway towards sustainability. In this work, a hybrid PV power-to-hydrogen, storage and fuel cell system is proposed to satisfy the domestic load of a residential building. Identifying alkaline as a mandatory electrolysis technology, the performance of alkaline electrolysis cells is assessed considering the inclusion of a two-switch buck-boost converter. Following a comprehensive formulation with respect to each distinguished system component, the balance condition at DC and AC buses is determined. The proposed configuration is evaluated, taking into account PV systems of different ratings, namely 3 kW, 5 kW and 7 kW. Based on actual data relating to both PV generation and domestic load for the year 2020, the obtained results from the annual simulations are compared with feed-in tariff and net-metering schemes. According to the results, PV capacity firming is achieved, creating great opportunities for autonomy enhancement, not only for electricity, but also in other energy sectors