45 research outputs found
Efficacy of short and long acting bronchodilators in mechanically ventilated patients with chronic obstructive pulmonary disease
No full textThe delivery of bronchodilators -particularly beta2-agonists- by metered dose inhaler (MDI) in mechanically ventilated. COPD patients have received considerable interest in recent years. This is because the use of an MDI has several advantages over the nebulizer in terms of ease of administration reduced cost and safety. Provided that the technique of administration is proper MDIs seem to be as effective as nebulizers despite a significantly lower dose of bronchodilator delivered by the MDI. While several studies have examined the effect of various ventilatory parameters (like tidal volume increase application of an end-inspiratory pause different flow/time profile different flow rate) on bronchodilator efficacy the effect of spontaneous respiratory efforts on beta2-agomst induced bronchodilation has never been studied in humans. Furthermore, while the duration of the bronchodilator response to short as well as long-acting beta2-agonists has been established in spontaneously breathing COPD patients it has not been studied in mechanically ventilated patients with COPD exacerbation. Hence, the following questions were studied: - duration of the bronchodilator effect induced by the short-acting beta2-agonist salbutamol, - influence of respiratory efforts on beta2-agonist induced bronchodilation in mechanically ventilated COPD patients. - duration of the bronchodilator effect induced by the long-acting beta2-agonist salmeterol in mechanically ventilated COPD patients. The resulting main conclusions were the following: In mechanically ventilated patients with COPD exacerbation administration of the short-acting beta2-agonist salbutamol as well as the long-acting beta2-agonist salmeterol by MDI and a spacer device causes significant reduction of respiratory resistance indices (Rmin and Rmax), In mechanically ventilated patients with COPD exacerbation administration of 600 μg of the short-acting, beta2-agonist salbutamol caused a significant bronchodilator response which was evident at 15 minutes after administration and remained relatively constant for approximately 3 hours although significant inter-patient variability was noticed. - The magnitude of bronchodilation induced by salbutamol delivered by an MDI and a spacer device in mechanically ventilated COPD patients is not affected by the presence or absence of active respiratory efforts. - In mechanically ventilated patients with COPD exacerbation administration of 100 μg of the long-acting beta2-agonist salmeterol caused a significant bronchodilator response which was evident at 30 minutes after administration and remained relatively constant for approximately 8 hours. Duration of bronchodilator effect varied significantly among patients precluding definite conclusions regarding an optimum dosing schedule which should be titrated according to objective indices of bronchodilation.Η χορήγηση βρογχοδιασταλτικών φαρμάκων με κύριο εκπρόσωπο τους β2-αγωνιστές σε μηχανικά αεριζόμενους ασθενείς με χρόνια αποφρακτική πνευμονοπάθεια (ΧΑΠ) μέσω δοσιμετρικής συσκευής (ΔΣ) έχει αποκτήσει ιδιαίτερο ενδιαφέρον τα τελευταία χρόνια. Οι ΔΣ εμφανίζουν σημαντικά πλεονεκτήματα σε σύγκριση με τους νεφελοποιητές όσον αφορά την ευκολία χρήσης το κόστος και την ασφάλεια. Υπό την προϋπόθεση δε της τήρησης ορθής τεχνικής χορήγησης ο συνδυασμός ΔΣ-αεροθαλάμου φαίνεται να είναι εξίσου αποτελεσματικός με τους νεφελοποιητές παρά τη χορήγηση σημαντικά χαμηλότερης δόσης φαρμάκου. Ενώ λοιπόν έχει διερευνηθεί η επίδραση των διαφόρων παραμέτρων του αναπνευστήρα (όπως π.χ. η αύξηση του αναπνεόμενου όγκου η προσθήκη τελοεισπνευστικής παύσης το σχήμα και το μέγεθος της εισπνευστικής ροής) στην αποτελεσματικότητα των χορηγουμένων β2-αγωνιστών, η επίδραση της ύπαρξης αναπνευστικών προσπαθειών του ασθενούς στο βρογχοδιασταλτικό αποτέλεσμα δεν έχει μελετηθεί. Πέραν τούτου, σε αντίθεση με μη διασωληνωμένους ασθενείς όπου η διάρκεια δράσης τόσο των βραχείας όσο και των μακράς διάρκειας δράσης β2-αγωνιστών είναι γνωστή η διάρκεια του βρογχοδιασταλτικού αποτελέσματος των φαρμάκων αυτών δεν έχει μελετηθεί σε διασωληνωμένους ασθενείς. Η παρούσα διατριβή μελέτησε τα έξης ερωτήματα: - τη διάρκεια του βρογχοδιασταλτικού αποτελέσματος του βραχείας διάρκειας δράσης β2-αγωνιστή σαλβουταμόλη, - τη διάρκεια του βρογχοδιασταλτικού αποτελέσματος του μακράς διάρκειας δράσης β2-αγωνιστή σαλμετερόλη, - την επίδραση των αναπνευστικών προσπαθειών του ασθενούς επί του μεγέθους της προκαλούμενης βρογχοδιαστολής. Τα συμπεράσματα που προέκυψαν από τις μελέτες αυτές είναι τα ακολούθα: - Σε μηχανικά αεριζόμενους ασθενείς με έξαρση ΧΑΠ η χορήγηση τόσο του βραχείας διάρκειας δράσης β2-αγωνιστή σαλβουταμόλη όσο και του μακράς διάρκειας δράσης β2-αγωνιστή σαλμετερόλη με ΔΣ και αεροθάλαμο οδηγεί σε σημαντική ελάττωση των εισπνευστικών αντιστάσεων (Rmin και Rmax). - Σε διασωληνωμένους ασθενείς με έξαρση ΧΑΠ η χορήγηση 600 μg σαλβουταμόλης μέσω ΔΣ και αεροθαλάμου οδηγεί σε σημαντική βρογχοδιασταλτική απάντηση η οποία είναι εμφανής στα 15 λεπτά μετά τη χορήγησή της και διαρκεί περίπου 3 ώρες. Όσον αφορά δε τη διάρκεια της βρογχοδιασταλτικής απάντησης παρατηρήθηκε μη προβλέψιμη υψηλού βαθμού διακύμανση μεταξύ των ασθενών γεγονός το οποίο δεν επιτρέπει την έκδοση συγκεκριμένων οδηγιών αναφορικά με το βέλτιστο δοσολογικό σχήμα. - Η ύπαρξη αναπνευστικών προσπαθειών του ασθενούς κατά τη διάρκεια μοντέλου υποστηριζόμενου μηχανικού αερισμού τύπου pressure support δεν επηρεάζει την αποτελεσματικότητα της χορηγούμενης σαλβουταμόλης. - Σε διασωληνωμένους ασθενείς με έξαρση ΧΑΠ η χορήγηση 100 μg σαλμετερόλης μέσω ΔΣ και αεροθαλάμου οδηγεί σε σημαντική βρογχοδιασταλτική απάντηση η οποία είναι εμφανής στα 30 λεπτά μετά τη χορήγηση της και διαρκεί περίπου 6 ώρες. Όσον αφορά δε τη διάρκεια της βρογχοδιασταλτικής απάντησης παρατηρήθηκε μη προβλέψιμη υψηλού βαθμού διακύμανση μεταξύ των ασθενών, γεγονός το οποίο δεν επιτρέπει την έκδοση συγκεκριμένων οδηγιών αναφορικά με το βέλτιστο δασολογικό σχήμα. Αντ’ αυτού το μεσοδιάστημα μεταξύ των δόσεων θα πρέπει να εξατομικεύεται βάσει συγκεκριμένων δεικτών βρογχοδιασταλτικής απάντησης
Forming parallel internets and enabling ultra-local economies
No full textThesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2008.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 105-109).Internet-based mobile communications have been increasing rapidly [5], yet there is little or no progress in platforms that enable applications for discovery, context-awareness and sharing of data and services in a peer-wise manner among collections of devices in the same physical area. This is important because proximate devices may need to communicate directly when no infrastructure is available, and because such local access may be an efficient alternative to connecting a large number of sensors, effectors, and people to a readily accessible, universal central system. This thesis presents the design, implementation and evaluation of Cerebro, a system that allows suitably equipped humans and objects in the same physical area to discover each other and share data and services. Cerebro offers two basic services: a presence service that propagates information about local devices through an automatically generated mesh network and an innovative data transport service to transfer data via this network. On top of these services, Cerebro offers an extensible Application Programming Interface (API). In a mobile mesh network with N devices, Cerebro offers an upper bound of O(N) on traffic overhead to maintain presence information at any part of the network and responsiveness to device arrival/departure events that take at most O(N) time to propagate throughout the network. This makes Cerebro a scalable and useful addition to mobile service delivery.by Polychronis Panagiotis Ypodimatopoulos.S.M
Carnet de J.D. CHAUPIN
No full textThis 199-page handbook is a monograph on Notre-Dame de Vaulx, a French village located in the Isère département of the Rhône-Alpes region, authored by J.D. CHAUPIN. It was completed in May 1958 and dedicated by the author to his grand-daughter Danielle Marthe CHAUPIN. The first fifty pages contain a glossary of more than 1500 words and the most popular expressions in matheysin patois.The version available here is a second-generation xerox copy of the manuscript collected by Jacqueline DUC, a specialist of matheysin patois.Ce carnet de 199 pages est une monographie sur le village de Notre-Dame de Vaulx, une commune française située dans le département de l'Isère et la région Rhône-Alpes, rédigée par M. J.D. CHAUPIN. Achevé en mai 1958, il est dédicacé à sa petite fille Danielle Marthe CHAUPIN. Il contient sur une cinquantaine de pages un glossaire de plus de 1500 mots ainsi que les expressions les plus courantes en patois matheysin.La version déposée ici est une photocopie de seconde génération du manuscrit réalisée par Jacqueline DUC, spécialiste des patois matheysins
Bayesian estimation of variance partition coefficients adjusted for imperfect test sensitivity and specificity
No full textThe variance partition coefficient (VPC) measures the clustering of infection/disease among individuals with a specific covariate pattern. Covariate-pattern-specific VPCs provide insight to the groups of individuals that exhibit great heterogeneity and should be targeted for intervention. VPCs should be taken into consideration when planning study designs, modeling data and estimating sample sizes. We present a Bayesian discrete mixed model for the estimation of covariate-pattern-specific VPCs when measurement of the infection/disease is based on an imperfect test. The utility of the presented model is demonstrated with three applications. In all cases, imperfect tests biased VPC estimates towards the null but corrected estimates could be obtained by modeling the sensitivity and specificity of the test procedure with beta distributions. The comparison of adjusted VPCs between the intercept only and the fitted models with higher level covariates explained the portion of heterogeneity in the data that was accounted for by the covariates
Impact of prolonged treatment with linezolid on the human gut flora
No full textSummaryA 79-year-old male was treated for 6 months with linezolid for prosthetic knee joint osteomyelitis. At the end of this 6-month period, quantitative stool cultures revealed partial loss of the normal gut flora and concomitant colonization by opportunistic pathogens such as Pseudomonas aeruginosa and other Gram-negatives. Follow-up cultures at 6 weeks after antibiotic discontinuation revealed restoration of the normal flora. Prolonged linezolid administration may lead to replacement of normal gut flora by pathogenic microorganisms, which under certain conditions might cause systemic infections
Josef Strzygowski's ungedrucktes Ms. aus dem Jahre 1888 über den Heiligen Berg Athos
No full textIn 1888, at the age of 26, Joseph Strzygowsky, the subsequently famousart historian of the University of Vienna, visited Mount Athos for the firsttime, and stayed there for seven weeks. The present study is the first publication of his detailed report about his research in the monasteries of Athos.The manuscript of this report still lies unpublished in the State Archives ofVienna (Haus-, Hof- und Staatsarchiv. PA XII. Türkei, Karton 276, LiasseXXVII) among a great mass of other official documents mainly concerningRussian infiltration in the area of Mount Athos. Its author had been orderedby the Austrian government to give an on-the-spot account of the situationin this sensitive area with regard to the spread of the tenets of Pan-Slavism.Leaving aside the Strzygowski report’s probable impact on Austrianpolicy towards Mount Athos, it comprises a complete description of MountAthos with respect to its physical geography, flora, road network, anchorages,and future ports. The Vienna delegate’s main contribution lies in his accountof the internal history of the monasteries and the constitution of the monasticrepublic. He was especially concerned with the problem of nationalities andthe obvious infiltration of the Russian element, which was doing its utmostto replace the other nationalities and particularly the Greeks, who werenumerous. In the brief table at the end of the report, Strzygowski’s generalconclusions about Athos a century ago are expressed in numerical terms
Reporting guidelines for diagnostic accuracy studies that use Bayesian latent class models (STARD-BLCM): Featured commentary
No full textSTARD-BLCM: Standards for the reporting of diagnostic accuracy studies that use Bayesian latent class models
No full textNew aesthetic in-house 3D-printed brackets: proof of concept and fundamental mechanical properties
No full textObjectives: Three-dimensional (3D) printing technology is an emerging manufacturing process for many orthodontic appliances, and the aim of this study was to evaluate the mechanical properties of resin-based materials as alternatives for the in-house preparation of orthodontic brackets. Material and Methods: Two types of 3D printed resins used for temporary (T) and permanent (P) crown fabrication were included in this study. Ten blocks from each resin were manufactured by a 3D printer and, after embedding them in acrylic resin, the samples were subjected to metallographic grinding and polishing, followed by instrumented indentation testing (IIT). Martens hardness (HM), indentation modulus (EIT), and elastic index (ηIT) were determined with a Vickers indenter recording force-indentation depth curves from each specimen. After calculating descriptive statistics, differences between material types were investigated with Wilcoxon rank sum test accounting for clustering of measurements within specimens at alpha = 5%. Results: No statistically significant differences in the mechanical properties of the two tested materials were seen: HM: median 279 N/mm2 (interquartile range [IQR] 275–287 N/mm2) for T and median 279 N/mm2 (IQR 270–285 N/mm2) for P (P value = 0.63); EIT: median 5548 MPa (IQR 5425–5834 MPa) for T and median 5644 (IQR 5420–5850 MPa) for P (P value = 0.84); ηIT: median 47.1% (46.0–47.7%) for T and median 46.0% (IQR 45.4–47.8%) for P (P value = 0.24). Conclusions: Under the limitations of this study, it may be concluded that the mechanical properties of the two 3D printed resins tested are equal, and thus, no differences in their clinical performance are expected. © 2022, The Author(s)
Critical appraisal of technologies to assess electrical activity during atrial fibrillation: a position paper from the European Heart Rhythm Association and European Society of Cardiology Working Group on eCardiology in collaboration with the Heart Rhythm Society, Asia Pacific Heart Rhythm Society, Latin American Heart Rhythm Society and Computing in Cardiology
No full textWe aim to provide a critical appraisal of basic concepts underlying signal recording and processing technologies applied for (i) atrial fibrillation (AF) mapping to unravel AF mechanisms and/or identifying target sites for AF therapy and (ii) AF detection, to optimize usage of technologies, stimulate research aimed at closing knowledge gaps, and developing ideal AF recording and processing technologies. Recording and processing techniques for assessment of electrical activity during AF essential for diagnosis and guiding ablative therapy including body surface electrocardiograms (ECG) and endo- or epicardial electrograms (EGM) are evaluated. Discussion of (i) differences in uni-, bi-, and multi-polar (omnipolar/Laplacian) recording modes, (ii) impact of recording technologies on EGM morphology, (iii) global or local mapping using various types of EGM involving signal processing techniques including isochronal-, voltage- fractionation-, dipole density-, and rotor mapping, enabling derivation of parameters like atrial rate, entropy, conduction velocity/direction, (iv) value of epicardial and optical mapping, (v) AF detection by cardiac implantable electronic devices containing various detection algorithms applicable to stored EGMs, (vi) contribution of machine learning (ML) to further improvement of signals processing technologies. Recording and processing of EGM (or ECG) are the cornerstones of (body surface) mapping of AF. Currently available AF recording and processing technologies are mainly restricted to specific applications or have technological limitations. Improvements in AF mapping by obtaining highest fidelity source signals (e.g. catheter-electrode combinations) for signal processing (e.g. filtering, digitization, and noise elimination) is of utmost importance. Novel acquisition instruments (multi-polar catheters combined with improved physical modelling and ML techniques) will enable enhanced and automated interpretation of EGM recordings in the near future.Signal Processing SystemsBiomechanical Engineerin
