Stream Learning in Energy IoT Systems: A Case Study in Combined Cycle Power Plants

The prediction of electrical power produced in combined cycle power plants is a key challenge in the electrical power and energy systems field. This power production can vary depending on environmental variables, such as temperature, pressure, and humidity. Thus, the business problem is how to predict the power production as a function of these environmental conditions, in order to maximize the profit. The research community has solved this problem by applying Machine Learning techniques, and has managed to reduce the computational and time costs in comparison with the traditional thermodynamical analysis. Until now, this challenge has been tackled from a batch learning perspective, in which data is assumed to be at rest, and where models do not continuously integrate new information into already constructed models. We present an approach closer to the Big Data and Internet of Things paradigms, in which data are continuously arriving and where models learn incrementally, achieving significant enhancements in terms of data processing (time, memory and computational costs), and obtaining competitive performances. This work compares and examines the hourly electrical power prediction of several streaming regressors, and discusses about the best technique in terms of time processing and predictive performance to be applied on this streaming scenario.This work has been partially supported by the EU project iDev40. This project has received funding from the ECSEL Joint Undertaking (JU) under grant agreement No 783163. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and Austria, Germany, Belgium, Italy, Spain, Romania. It has also been supported by the Basque Government (Spain) through the project VIRTUAL (KK-2018/00096), and by Ministerio de Economía y Competitividad of Spain (Grant Ref. TIN2017-85887-C2-2-P)

Computation in One-Dimensional Piecewise Maps

In this paper we show that the one-dimensional Piecewise Affine Maps (PAMs) are equivalent to planar Pseudo-Billiard Systems (PBSs) or so called “strange billiards”. The reachability problem for PAMs is still open, however the more general model of rational onedimensional maps is shown to be universal with undecidable reachability problem

Are we asking the right questions to people with Achilles tendinopathy? The best questions to distinguish mild versus severe disability to improve your clinical management

Objective: Determine the capacity of individual items on the Tendinopathy Severity Assessment – Achilles (TENDINS-A), Foot and Ankle Outcome Score (FAOS), and Victorian Institute of Sports Assessment – Achilles (VISA-A) to differentiate patients with mild and severe tendon-related disability in order to provide clinicians the best questions when they are consulting patients with Achilles tendinopathy. Design: Cross-sectional. Participants: Seventy participants with Achilles tendinopathy (61.4% mid-portion only, 31.4% insertional only, 7.2% both). Outcome measures: The discrimination index was determined for each TENDINS-A, FAOS, and VISA-A item to determine if items could discriminate between mild and severe disability. A Guttman analysis for polytomous items was conducted. Results: All 62 tems from the TENDINS-A, FAOS, and VISA-A were ranked with the best items relating to pain with physical tendon loading, time for pain to settle following aggravating activities and time for the tendon to ‘warm-up’ following inactivity. Conclusions: Pain with loading the Achilles tendon, time for pain to settle following aggravating activity, as well as time taken for the tendon symptoms to subside after prolonged sitting or sleeping are the best questions indicative of the severity of disability in patients with Achilles tendinopathy. These questions can assist clinicians with assessing baseline severity and monitoring treatment response.</p

Are we asking the right questions to people with Achilles tendinopathy? The best questions to distinguish mild versus severe disability to improve your clinical management

Objective: Determine the capacity of individual items on the Tendinopathy Severity Assessment – Achilles (TENDINS-A), Foot and Ankle Outcome Score (FAOS), and Victorian Institute of Sports Assessment – Achilles (VISA-A) to differentiate patients with mild and severe tendon-related disability in order to provide clinicians the best questions when they are consulting patients with Achilles tendinopathy. Design: Cross-sectional. Participants: Seventy participants with Achilles tendinopathy (61.4% mid-portion only, 31.4% insertional only, 7.2% both). Outcome measures: The discrimination index was determined for each TENDINS-A, FAOS, and VISA-A item to determine if items could discriminate between mild and severe disability. A Guttman analysis for polytomous items was conducted. Results: All 62 tems from the TENDINS-A, FAOS, and VISA-A were ranked with the best items relating to pain with physical tendon loading, time for pain to settle following aggravating activities and time for the tendon to ‘warm-up’ following inactivity. Conclusions: Pain with loading the Achilles tendon, time for pain to settle following aggravating activity, as well as time taken for the tendon symptoms to subside after prolonged sitting or sleeping are the best questions indicative of the severity of disability in patients with Achilles tendinopathy. These questions can assist clinicians with assessing baseline severity and monitoring treatment response.</p

Competitive evaporation in arrays of droplets

We consider the evaporation of periodic arrays of initially equal droplets in two-dimensional systems with open (absorbing) boundaries. Our study is based on the numerical solution of the Cahn-Hilliard equation. We show that due to cooperative effects the droplets which are further from the boundary may evaporate earlier than those in the boundary¿s vicinity. The time evolution of the overall amount of matter in the system is also studied

Evaporation and coarsening dynamics with open boundaries

We present a study of the evaporation dynamics of a substance undergoing a coarsening process. The system is modeled by the Cahn-Hilliard equation with absorbing boundaries. We have found that the dynamics, although of a diffusive nature, is much slower than the usual one without coarsening. Analytical and simulation results are in reasonable agreement

Olanzapine compared to quetiapine in adolescents with a first psychotic episode

Objective: To compare the efficacy, safety, and tolerability of olanzapine and quetiapine in adolescents with first episode psychosis. Method: Fifty adolescents (age 16 ± 1.25) with a first episode of psychosis were randomized to quetiapine or olanzapine in a 6-month open label study. Efficacy and side effect scales, as well as vital signs and laboratory data were recorded at baseline, 7, 15, 30, 90, and 180 days (end of study). Results: Out of the total sample included in the study, 32 patients completed the trial (quetiapine n = 16, olanzapine n = 16). Patients in both treatment groups had a significant reduction in all clinical scales with the exception of the negative scale of the Positive and Negative Symptom Scale (PANSS) for olanzapine and the general psychopathology scale of the PANSS for quetiapine. The only difference between treatment arms on the clinical scales was observed on the patients' strength and difficulties questionnaire (SDQ) scale, with greater improvement for olanzapine. Patients on olanzapine gained 15.5 kg and patients on quetiapine gained 5.5 kg. Conclusion: Olanzapine and quetiapine reduced psychotic symptoms in this adolescent sample. Patients on olanzapine gained significantly more weight. Side effects with both drugs seemed to be more prevalent than those reported in adult studies

Thermoprotection by a cell membrane-localized metacaspase in a green alga

Caspases are restricted to animals, while other organisms, including plants, possess metacaspases (MCAs), a more ancient and broader class of structurally related yet biochemically distinct proteases. Our current understanding of plant MCAs is derived from studies in streptophytes, and mostly in Arabidopsis (Arabidopsis thaliana) with 9 MCAs with partially redundant activities. In contrast to streptophytes, most chlorophytes contain only 1 or 2 uncharacterized MCAs, providing an excellent platform for MCA research. Here we investigated CrMCA-II, the single type-II MCA from the model chlorophyte Chlamydomonas (Chlamydomonas reinhardtii). Surprisingly, unlike other studied MCAs and similar to caspases, CrMCA-II dimerizes both in vitro and in vivo. Furthermore, activation of CrMCA-II in vivo correlated with its dimerization. Most of CrMCA-II in the cell was present as a proenzyme (zymogen) attached to the plasma membrane (PM). Deletion of CrMCA-II by genome editing compromised thermotolerance, leading to increased cell death under heat stress. Adding back either wild-type or catalytically dead CrMCA-II restored thermoprotection, suggesting that its proteolytic activity is dispensable for this effect. Finally, we connected the non-proteolytic role of CrMCA-II in thermotolerance to the ability to modulate PM fluidity. Our study reveals an ancient, MCA-dependent thermotolerance mechanism retained by Chlamydomonas and probably lost during the evolution of multicellularity.A plasma membrane-localized metacaspase mediates membrane fluidity and confers thermotolerance in Chlamydomonas reinhardtii independently of its proteolytic activity

High-resolution ultrasound tendon-to-bone distances in partial and complete finger flexor A2 pulley ruptures simulated in human cadaver dissection: toward understanding imaging of partial pulley ruptures

Introduction: The A2 pulley tear is the most common injury in rock climbing. Whereas complete A2 pulley ruptures have been extensively researched, studies focused on partial A2 pulley ruptures are lacking. A2 pulleys rupture distally to proximally. High-resolution ultrasound imaging is considered the gold-standard tool for diagnosis and the most relevant ultrasound measurement is the tendon-to-bone distance (TBD), which increases when the pulley ruptures. The purpose of this study was to establish tendon-to-bone distance values for different sizes of partial A2 pulley ruptures and compare these values with those of complete ruptures.Material and methods: The sample consisted of 30 in vitro fingers randomly assigned to 5 groups: G1, no simulated tear (control); G2, simulated 5 mm tear (low-grade partial rupture); G3, simulated 10 mm tear (medium-grade partial rupture); G4, simulated 15 mm tear (high-grade partial rupture); and G5, simulated 20 mm or equivalent tear (complete rupture). A highly experienced sonographer blinded to the randomization process and dissections examined all fingers.Results: The tendon-to-bone distance measurements (medians and interquartile ranges) were as follows: G1, 0.95 mm (0.77–1.33); G2, 2.11 mm (1.78–2.33); G3, 2.28 mm (1.95–2.42); G4, 3.06 mm (2.79–3.28); and G5, 3.66 mm (3.55–4.76). Significant differences were found between non-torn pulleys and simulated partial and complete pulley ruptures.Discussion: In contrast, and inconsistent with other findings, no significant differences were found among the different partial rupture groups. In conclusion, the longer the partial pulley rupture, the higher the tendon-to-bone distance value. The literature is inconsistent regarding the tendon-to-bone distance threshold to diagnose a partial A2 pulley rupture. The minimum tendon-to-bone distance value for a partial rupture was 1.6 mm, and tendon-to-bone distance values above 3 mm suggest a high-grade partial pulley rupture (15 mm incision) or a complete pulley rupture

Revealing legacy effects of extreme droughts on tree growth of oaks across the Northern Hemisphere

Forests are undergoing increasing risks of drought-induced tree mortality. Species replacement patterns following mortality may have a significant impact on the global carbon cycle. Among major hardwoods, deciduous oaks (Quercus spp.) are increasingly reported as replacing dying conifers across the Northern Hemisphere. Yet, our knowledge on the growth responses of these oaks to drought is incomplete, especially regarding post-drought legacy effects. The objectives of this study were to determine the occurrence, duration, and magnitude of legacy effects of extreme droughts and how that vary across species, sites, and drought characteristics. The legacy effects were quantified by the deviation of observed from expected radial growth indices in the period 1940–2016. We used stand-level chronologies from 458 sites and 21 oak species primarily from Europe, north-eastern America, and eastern Asia. We found that legacy effects of droughts could last from 1 to 5 years after the drought and were more prolonged in dry sites. Negative legacy effects (i.e., lower growth than expected) were more prevalent after repetitive droughts in dry sites. The effect of repetitive drought was stronger in Mediterranean oaks especially in Quercus faginea. Species-specific analyses revealed that Q. petraea and Q. macrocarpa from dry sites were more negatively affected by the droughts while growth of several oak species from mesic sites increased during post-drought years. Sites showing positive correlations to winter temperature showed little to no growth depression after drought, whereas sites with a positive correlation to previous summer water balance showed decreased growth. This may indicate that although winter warming favors tree growth during droughts, previous-year summer precipitation may predispose oak trees to current-year extreme droughts. Our results revealed a massive role of repetitive droughts in determining legacy effects and highlighted how growth sensitivity to climate, drought seasonality and species-specific traits drive the legacy effects in deciduous oak species