Evidence of an active Enso and Pdo during the mid-Holocene from a Costa Rican speleothem

The El Nino/Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) are the most important sources of interannual to multidecadal climate variability in the tropics. A high resolution ({dollar}3.8 years/sample) paleoclimate record of Central American rainfall variability has been reconstructed from a U/Th-dated stalagmite (7890 to 6490 yrs B.P.) from Costa Rica to constrain the onset and variability of ENSO throughout the Holocene, and to determine its role in generating regional climate anomalies. I suggest drier conditions, forced by El Nino and/or the PDO, are represented by higher delta 18O values, and are correlative with higher delta13C values, indicating that soil respiration rates are affected by regional climate variability, which are recorded in the speleothem stratigraphy grayscale values. This study provides new evidence, based on 3 different proxies, that throughout the middle Holocene, rainfall was varying at interdecadal timescales, which I attribute to low frequency variability in ENSO and the PDO

Factorization of computations in Bayesian networks: Interpretation of factors

© Springer International Publishing Switzerland 2017. Given a Bayesian network (BN) relative to a set I of discrete random variables, we are interested in computing the probability distribution PS, where the target S is a subset of I. The general idea is to express PS in the form of a product of factors whereby each factor is easily computed and can be interpreted in terms of conditional probabilities. In this paper, a condition statingwhen PS can be written as a product of conditional probability distributions is called a non-pathology condition. This paper also considers an interpretation of the factors involved in computing marginal probabilities in BNs and a representation of the probability target as a Bayesian network of level two. Establishing such a factorization and interpretations is indeed interesting and relevant in the case of large BNs

Dynamic analysis of semi-flexible multibody systems: Coordinates relatives method

International audienceThis work presents the dynamic modelling of a multibody systems in cross form constituted of a central body which is connected four flexible arms, at each end of arm is connected a rotor. A particular attention is given to the influence of flexibility on the dynamic behaviour of system. For elaborate the complete dynamic model, one consider the sub-structuration technique in using the Lagrangian approach based on the relatives coordinates method of central body. One establishes then the mathematics equations permitting to obtain the dynamic model of motion for the simulation and the control study. The aerodynamic loads and the gravity force are taking into account for the dynamic complete model. At the end, one considers the case of stationary flight of a miniature Quadrotor. The numerical results permit to simulate the motion of Quadrirotor in flight. But also to compare the flexible and rigid model in order to resort the flexibility effects

Effect of laser processing parameters and glass type on topology of micro-channels

Traditional processes to manufacture micro-fluidic devices include standard lithography, electron beam writing and photo-patterning. These techniques are well established but most are limited to surface micro-fabrication. Laser micro-machining provides an alternative for microfabrication of devices. This paper presents Design of Experiment models for the fabrication of micro-channel structures with four different types of glass, soda-lime, fused-silica, borosilicate and quartz. A 1.5kW CO2 laser with 90 μm spot size was used to fabricate micro-channels on the surface of glass sheets. Power, P, pulse repetition frequency, PRF, and translation speed, U, were set as control parameters. The resulting geometry of the channel (depth and width) and transmission capabilities were measured and analyzed. A comparison of the results of this experimental testing with the four glass types showed that quartz and fused-silica glasses would have better channel topologies for chemical sensing applications

Inhalation characteristics of asthma patients, COPD patients and healthy volunteers with the Spiromax® and Turbuhaler® devices: a randomised, cross-over study.

BACKGROUND: Spiromax® is a novel dry-powder inhaler containing formulations of budesonide plus formoterol (BF). The device is intended to provide dose equivalence with enhanced user-friendliness compared to BF Turbuhaler® in asthma and chronic obstructive pulmonary disease (COPD). The present study was performed to compare inhalation parameters with empty versions of the two devices, and to investigate the effects of enhanced training designed to encourage faster inhalation. METHODS: This randomised, open-label, cross-over study included children with asthma (n = 23), adolescents with asthma (n = 27), adults with asthma (n = 50), adults with COPD (n = 50) and healthy adult volunteers (n = 50). Inhalation manoeuvres were recorded with each device after training with the patient information leaflet (PIL) and after enhanced training using an In-Check Dial device. RESULTS: After PIL training, peak inspiratory flow (PIF), maximum change in pressure (∆P) and the inhalation volume (IV) were significantly higher with Spiromax than with the Turbuhaler device (p values were at least <0.05 in all patient groups). After enhanced training, numerically or significantly higher values for PIF, ∆P, IV and acceleration remained with Spiromax versus Turbuhaler, except for ∆P in COPD patients. After PIL training, one adult asthma patient and one COPD patient inhaled <30 L/min through the Spiromax compared to one adult asthma patient and five COPD patients with the Turbuhaler. All patients achieved PIF values of at least 30 L/min after enhanced training. CONCLUSIONS: The two inhalers have similar resistance so inhalation flows and pressure changes would be expected to be similar. The higher flow-related values noted for Spiromax versus Turbuhaler after PIL training suggest that Spiromax might have human factor advantages in real-world use. After enhanced training, the flow-related differences between devices persisted; increased flow rates were achieved with both devices, and all patients achieved the minimal flow required for adequate drug delivery. Enhanced training could be useful, especially in COPD patients

The Inhalation Characteristics of Patients When They Use Different Dry Powder Inhalers

Background: The characteristics of each inhalation maneuver when patients use dry powder inhalers (DPIs) are important, because they control the quality of the emitted dose. Methods: We have measured the inhalation profiles of asthmatic children [CHILD; n=16, mean forced expiratory volume in 1 sec (FEV1) 79% predicted], asthmatic adults (ADULT; n=53, mean predicted FEV1 72%), and chronic obstructive pulmonary disease (COPD; n=29, mean predicted FEV1 42%) patients when they inhaled through an Aerolizer, Diskus, Turbuhaler, and Easyhaler using their “real-life” DPI inhalation technique. These are low-, medium-, medium/high-, and high-resistance DPIs, respectively. The inhalation flow against time was recorded to provide the peak inhalation flow (PIF; in L/min), the maximum pressure change (ΔP; in kPa), acceleration rates (ACCEL; in kPa/sec), time to maximum inhalation, the length of each inhalation (in sec), and the inhalation volume (IV; in liters) of each inhalation maneuver. Results: PIF, ΔP, and ACCEL values were consistent with the order of the inhaler's resistance. For each device, the inhalation characteristics were in the order ADULT>COPD>CHILD for PIF, ΔP, and ACCEL (p4 L and ΔP >4 kPa. Conclusion: The large variability of these inhalation characteristics and their range highlights that if inhalation profiles were used with compendial in vitro dose emission measurements, then the results would provide useful information about the dose patients inhale during routine use. The inhalation characteristics highlight that adults with asthma have greater inspiratory capacity than patients with COPD, whereas children with asthma have the lowest. The significance of the inhaled volume to empty doses from each device requires investigation

Modelling and control of a bidirectional rotors X4-flyer

International audienceThis paper presents in the first part the conception and construction of a mini 4 rotors helicopter for indoor and outdoor applications. The proposed UAV, named XSF, has a very manoeuvrable platform and is indicated to work in inaccessible spaces such as performing inspection tasks under bridges as well as inside pipes or tanks. Its main advantage with respect to classical 4 rotors helicopters is the ability of flipping two motors in order to obtain two more control inputs. This feature allows the XSF to have a better horizontal displacement or to create a yaw movement without translation. In the second part, we present a stabilization strategy around a position of equilibrium. The model is highly nonlinear, we use a methodology based on the linearization. The dynamic of the system involves six control inputs which will be computed to stabilize the engine with regard to external perturbations

Le toit comme outil de régulation environnementale : le cas montréalais

Cette recherche s’inscrit dans le cadre du programme interdisciplinaire de recherche Ignis Mutat Res et vise à éclairer l’univers de l’architecture sur la capacité des toits à amener des solutions efficaces aux problématiques environnementales dans un contexte urbain dense et à forte consommation d'énergie. La volonté de réduire l’empreinte écologique des villes est aujourd’hui bien présente dans le monde de la recherche architecturale et urbaine, ayant ainsi fait preuve de son importance. Pourtant, la réduction de l’empreinte écologique des villes serait une approche globale difficile à quantifier économiquement. Le manque de méthodologie standardisée fait en sorte que les travaux sur le sujet empruntent des démarches qui ne dépassent pas l’étape exploratoire. Dans ce contexte, le mémoire porte sur l’élaboration d’un dispositif numérique d’évaluation des potentialités des toits horizontaux comme un outil d’aide à la décision pour les interventions urbaines visant à réduire l’empreinte écologique des villes, en utilisant le cas de Montréal. Ce type de toit est abordé comme un territoire d’investigation en contribution aux préoccupations reliées à la gestion de l’eau et à l’atténuation des îlots de chaleur. Plus précisément, cette recherche porte sur trois secteurs de l'île de Montréal. Ces échantillons correspondent à deux types de formes urbaines (résidentielle versus commerciale ou industrielle) et sont décortiqués dans le but d’identifier les déséquilibres entre les espaces naturels, faisant référence aux espaces verts (jardins, parcs et canopées) et les étendues minérales occasionnées par l'urbanisation. Ces rapports exprimés en superficies démontrent que l’étendue des toits est assez considérable pour compenser le manque d’espaces naturels en ville. La végétalisation des toits à l’échelle d’un secteur pourrait donc atténuer considérablement les problèmes environnementaux liés aux îlots de chaleur et à la gestion du ruissellement des eaux de pluie. La stratégie consistant à explorer l'hypothèse des 50 % de naturel versus 50 % de minéral pourrait contribuer grandement à l’autonomisation des villes et à la diminution de leurs dépendances vis-à-vis des ressources fossiles.This research is part of the interdisciplinary research program Ignis Mutat Res and aims to inform the world of architecture on the potential of roofs to bring effective solutions to environmental problems in a dense urban setting with high energy consumption. The need to reduce the ecological footprint of cities is now greatly present in the world of architectural and urban research, having previously demonstrated its importance. However, the reduction of the ecological footprint of cities remains a difficult global approach to quantify economically. The lack of standardized methodology maintain the studies on the subject at a perpetual exploratory stage. In this context, the research focuses on the development of a digital system to assess the horizontal roofs' potentiality as a decision making support tool for urban interventions to reduce the ecological footprint of cities, using in this case the city of Montreal. This type of roof is considered as an area of investigation in relation to concerns associated to water management and mitigation of heat islands. Moreover, this research focuses on three areas of the island of Montreal. These samples correspond to two types of urban typologies (residential versus commercial or industrial) which are dissected in order to identify imbalances between natural, referring here to green areas (gardens, parks and canopies) and mineral surfaces caused by urbanization. These balances or imbalances expressed in ratios between types of surfaces demonstrate that the roof area is broad enough to compensate for the lack of natural areas in the city. Roof greening across a sector could therefore significantly reduce the environmental issues associated with heat islands and managing runoff of rainwater. The strategy brought forward is to explore the hypothesis of a balance of 50 % of green versus a 50 % of mineral, which could contribute greatly to the empowerment of cities and the reduction of their fossil fuel dependency