Unsupervised learning as a complement to convolutional neural network classification in the analysis of saccadic eye movement in spino-cerebellar ataxia type 2

IWANN es un congreso internacional que se celebra bienalmente desde 1991. Su campo de estudio se centra en la fundamentación y aplicación de las distintas técnicas de Inteligencia Computacional : Redes Neuronales Artificiales, Algoritmos Genéticos, Lógica Borrosa, Aprendizaje Automático. En esta edición han participado 150 investigadores.This paper aims at assessing spino-cerebellar type 2 ataxiaby classifying electrooculography records into registers corresponding to healthy, presymptomatic and ill individuals. The primary used technique is the convolutional neural network applied to the time series of eye movements, called saccades. The problem is exceptionally hard, though, because the recorded saccadic movements for presymptomatic cases often do not substantially di er from those of healthy individuals. Precisely this distinction is of the utmost clinical importance, since early intervention on presymptomatic patients can ameliorate symptoms or at least slow their progression. Yet, each register contains a number of saccades that, although not consistent with the current label, have not been considered indicative of another class by the examining physicians. As a consequence, an unsupervised learning mechanism may be more suitable to handle this form of misclassi cation. Thus, our proposal introduces the k-means approach and the SOM method, as complementary techniques to analyse the time series. The three techniques operating in tandem lead to a well performing solution to this diagnosis problem.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Universidad de Granada, Universitat Politècnica de Catalunya, Universidad de Las Palmas de Gran Canaria, Springe

Material properties of Islamic paper

In contrast to scientific research focussing on European paper, there is a significant gap in our knowledge of Islamic papermaking. This research surveys the evidence of techniques and materials typically used in Islamic papermaking, to deduce what might be considered as the most significant characteristics. A substantial collection of 228 Islamic papers (~18th–20th century) was characterized using chemical analytical methods: surface profilometry, gloss measurements, specular vs. diffuse reflectance ratio at 457 nm, scanning electron microscopy and infrared spectroscopy for identification of polishing, iodine test for identification of starch, Raspail test for identification of rosin, and fibre furnish analysis. Morphological analysis was performed to examine the presence of watermarks and sieve patterns. In addition, acidity and degree of polymerization of cellulose in paper were determined to explore the average material state of paper in the collection. Near infrared spectroscopic data of the collection were correlated to chemical properties with the aid of multivariate data analysis methods. Four different models were developed focusing on two main characteristics of Islamic paper: two for identification of polishing and starch, and two quantitative models to determine the acidity and degree of polymerization of cellulose in paper. While no single defining characteristic of Islamic paper was identified, 88 % of all papers in the studied collection either contain starch or are polished, or both. ~2 % of papers contain rosin. The majority of papers are neutral to mildly acidic, which is in contrast to their extensive degradation: ~69 % have DP < 1000. Polishing and starch appear to be associated with current values of pH and DP. The developed non-destructive characterization methodology could be applied to Islamic collections in libraries and archives to expand the database with the material properties of papers of known age and provenance and thus better understand geographic and temporal distributions of papermaking practices in Islamic countries

Non-destructive collection survey of the historical Classense Library. Part I: Paper characterisation

An innovative survey was conducted of the collections of the historical Biblioteca Classense, located in the urban area of Ravenna (Northern Italy). The survey aimed to evaluate the current conservation state of the book collections, where 297 paper-based items, including incunabula, manuscripts and books, dating from the 14th to the 20th century, were selected for analysis. This innovative survey was carried out non-destructively by assessing degradation visually and by measuring NIR spectral data followed by multivariate data analysis. Chemical and physical paper properties, important for paper characterisation and implementation of conservation strategies were determined, including paper type, pH, degree of polymerisation (DP), tensile strength, lignin, protein, and rosin content. This survey provided a significant quantitative dataset for rag paper covering a 600-year period. The analysis of DP changes over time allowed the first experimental estimation of the rate constant for historical rag paper, i.e., (4.2 ± 0.6)·10−7 year−1, which was validated with predictions based on the Collections Demography dose response function for historic paper taking into account the past climate in Ravenna. Statistical methods were employed to describe the correlations between the measured variables and different features of the books, suggesting that the degree of polymerisation can be used as a general proxy for rag paper mechanical strength

Determination of mechanical properties of historical paper based on NIR spectroscopy and chemometrics - a new instrument

Due to sampling restrictions in the analysis of cultural heritage materials, non-destructive approaches are intensively sought for. While NIR spectrometry has rarely been used for this purpose due to the complexity of the spectra, chemometric methods can be used to extract the necessary information. For the purpose of determination of mechanical properties of historical paper, partial least squares approach was used and it is shown that tensile strength, and tensile strength after folding, can be estimated based on NIR spectra. As the mechanical properties of paper-based objects define their accessibility, a new dispersive portable instrument was built, which will enable us to rapidly survey the condition of library and archival collections

Exercise Performance of Lowlanders with Chronic Obstructive Pulmonary Disease Acutely Exposed to 2048 m: A Randomized Cross-Over Trial

Background: Amongst the millions of travelers to high altitude worldwide are many with chronic obstructive pulmonary disease (COPD), but data regarding the effects of acute exposure to altitude on exercise performance are limited. The current study investigated how acute exposure to moderate altitude influences exercise performance in COPD patients, providing novel insights to the underlying physiological mechanisms. Methods: Twenty-nine COPD patients, GOLD grade 2-3, median (quartile) forced expiratory volume in 1 second (FEV$_1$) of 60% predicted (46; 69) performed cycling incremental ramp exercise test (IET) at 490 m and after acute exposure of 2-6 hours to 2048 m or vice versa, according to a randomized cross-over design. Exercise performance and breath-by-breath analyses of the last 30 seconds of each IET were compared between locations. Results: At 2048 m compared to 490 m, the maximum power output (Wmax) was 77 watts (62;104) vs 88 watts (75;112), median reduction 5 watts (95% CI, 2 to 8, P<0.05), corresponding to a median reduction of 6% (95% CI, 2 to 11, P<0.05) compared to 490 m. The peak oxygen uptake (V'O$_2$peak) was 70% predicted (56;86) at 2048 m vs 79% predicted (63;90) at 490 m, median reduction of 6% (95% CI, 3 to 9, P<0.05). The oxygen saturation by pulse oximetry (SpO$_2$) at 2048 m was reduced by 8% (95% CI, 4 to 9, P<0.05) compared to 490 m. The minute ventilation (V'$_E$) increased by 2.8L/min (95% CI, 0.9 to 4.2, P<0.05) at 2048 m. The maximum heart rate and the subjective sense of dyspnea and leg fatigue did not change. Conclusion: Lowlanders with moderate-to-severe COPD acutely exposed to 2048 m reveal small but significant reduction in cycling IET along with a reduced V'O$_2$peak. As dyspnea perception and maximal heart rate were unchanged, the lower blood oxygenation and exaggerated ventilatory response were culprit factors for the reduced performance

Hyperoxia improves exercise capacity in cardiopulmonary disease: a series of randomised controlled trials

Background: The aim of this study was to investigate the overall and differential effect of breathing hyperoxia (inspiratory oxygen fraction (F$_{IO_{2}}$) 0.5)versusplacebo (ambient air,F$_{IO_{2}}$0.21) to enhance exercise performance in healthy people, patients with pulmonary vascular disease (PVD) with precapillary pulmonary hypertension (PH), COPD, PH due to heart failure with preserved ejection fraction (HFpEF) and cyanotic congenital heart disease (CHD) using data from five randomised controlled trials performed with identical protocols. Methods: 91 subjects (32 healthy, 22 with PVD with pulmonary arterial or distal chronic thromboembolic PH, 20 with COPD, 10 with PH in HFpEF and seven with CHD) performed two cycle incremental (IET) and two constant work-rate exercise tests (CWRET) at 75% of maximal load (W$_{max}$), each with ambient air and hyperoxia in single-blinded, randomised, controlled, crossover trials. The main outcomes were differences in W$_{max}$(IET) and cycling time (CWRET) with hyperoxiaversusambient air. Results: Overall, hyperoxia increased W$_{max}$by +12 W (95% CI: 9–16, p<0.001) and cycling time by +6:13 min (4:50–7:35, p<0.001), with improvements being highest in patients with PVD (W$_{max}$/min: +18%/+118%versusCOPD: +8%/+60%, healthy: +5%/+44%, HFpEF: +6%/+28%, CHD: +9%/+14%). Conclusion: This large sample of healthy subjects and patients with various cardiopulmonary diseases confirms that hyperoxia significantly prolongs cycling exercise with improvements being highest in endurance CWRET and patients with PVD. These results call for studies investigating optimal oxygen levels to prolong exercise time and effects on training

A view of Internet Traffic Shifts at {ISP} and {IXPs} during the {COVID}-19 Pandemic

Due to the COVID-19 pandemic, many governments imposed lockdowns that forced hundreds of millions of citizens to stay at home. The implementation of confinement measures increased Internet traffic demands of residential users, in particular, for remote working, entertainment, commerce, and education, which, as a result, caused traffic shifts in the Internet core. In this paper, using data from a diverse set of vantage points (one ISP, three IXPs, and one metropolitan educational network), we examine the effect of these lockdowns on traffic shifts. We find that the traffic volume increased by 15-20% almost within a week – while overall still modest, this constitutes a large increase within this short time period. However, despite this surge, we observe that the Internet infrastructure is able to handle the new volume, as most traffic shifts occur outside of traditional peak hours. When looking directly at the traffic sources, it turns out that, while hypergiants still contribute a significant fraction of traffic, we see (1) a higher increase in traffic of non-hypergiants, and (2) traffic increases in applications that people use when at home, such as Web conferencing, VPN, and gaming. While many networks see increased traffic demands, in particular, those providing services to residential users, academic networks experience major overall decreases. Yet, in these networks, we can observe substantial increases when considering applications associated to remote working and lecturing.EC/H2020/679158/EU/Resolving the Tussle in the Internet: Mapping, Architecture, and Policy Making/ResolutioNe

The High-Acceptance Dielectron Spectrometer HADES

HADES is a versatile magnetic spectrometer aimed at studying dielectron production in pion, proton and heavy-ion induced collisions. Its main features include a ring imaging gas Cherenkov detector for electron-hadron discrimination, a tracking system consisting of a set of 6 superconducting coils producing a toroidal field and drift chambers and a multiplicity and electron trigger array for additional electron-hadron discrimination and event characterization. A two-stage trigger system enhances events containing electrons. The physics program is focused on the investigation of hadron properties in nuclei and in the hot and dense hadronic matter. The detector system is characterized by an 85% azimuthal coverage over a polar angle interval from 18 to 85 degree, a single electron efficiency of 50% and a vector meson mass resolution of 2.5%. Identification of pions, kaons and protons is achieved combining time-of-flight and energy loss measurements over a large momentum range. This paper describes the main features and the performance of the detector system