2,179 research outputs found
Predicting Dynamics on Networks Hardly Depends on the Topology
Processes on networks consist of two interdependent parts: the network
topology, consisting of the links between nodes, and the dynamics, specified by
some governing equations. This work considers the prediction of the future
dynamics on an unknown network, based on past observations of the dynamics. For
a general class of governing equations, we propose a prediction algorithm which
infers the network as an intermediate step. Inferring the network is impossible
in practice, due to a dramatically ill-conditioned linear system. Surprisingly,
a highly accurate prediction of the dynamics is possible nonetheless: Even
though the inferred network has no topological similarity with the true
network, both networks result in practically the same future dynamics
Unexpected transformation of dissolved phenols to toxic dicarbonyls by hydroxyl radicals and UV light.
Water treatment systems frequently use strong oxidants or UV light to degrade chemicals that pose human health risks. Unfortunately, these treatments can result in the unintended transformation of organic contaminants into toxic products. We report an unexpected reaction through which exposure of phenolic compounds to hydroxyl radicals (•OH) or UV light results in the formation of toxic α,β-unsaturated enedials and oxoenals. We show that these transformation products damage proteins by reacting with lysine and cysteine moieties. We demonstrate that phenolic compounds react with •OH produced by the increasingly popular UV/hydrogen peroxide (H2O2) water treatment process or UV light to form toxic enedials and oxoenals. In addition to raising concerns about potential health risks of oxidative water treatment, our findings suggest the potential for formation of these toxic compounds in sunlit surface waters, atmospheric water, and living cells. For the latter, our findings may be particularly relevant to efforts to understand cellular damage caused by in vivo production of reactive oxygen species. In particular, we demonstrate that exposure of the amino acid tyrosine to •OH yields an electrophilic enedial product that undergoes cross-linking reaction with both lysine and cysteine residues
Flow Coefficients for Orifices in Base of Transpiration-Cooled Turbine Rotor Blade
Static tests on a segment of a transpiration-cooled turbine rotor blade with a wire-cloth shell were conducted to determine the flow coefficients associated with some representative metering orifices. Average flow coefficients from 0.96 to 0.79 were obtained for orifices of 0.031 to 0.102 inch diameter
Exploring efficacy and safety of oral Pirfenidone for progressive, non-IPF lung fibrosis (RELIEF) - a randomized, double-blind, placebo-controlled, parallel group, multi-center, phase II trial
Background: Pirfenidone is currently approved in the EU for the treatment of mild to moderate idiopathic pulmonary fibrosis (IPF) and offers a beneficial risk-benefit profile. However, there are several other, progressive fibrotic lung diseases, in which conventional anti-inflammatory therapy is not sufficiently effective and antifibrotic therapies may offer a novel treatment option. Methods/Design: We designed a study protocol for inclusion of patients with progressive fibrotic lung disease despite conventional anti-inflammatory therapy (EudraCT 2014–000861-32). The study population comprises patients with collagen-vascular disease-associated lung fibrosis (CVD-LF), fibrotic non-specific interstitial pneumonia (fNSIP), chronic hypersensitivity pneumonitis (cHP), and asbestos-related lung fibrosis (ALF). Disease progression needs to be proven by slope calculation of at least three Forced Vital Capacity (FVC) values obtained within 6–24 months prior to inclusion, documenting an annualized decline in percent predicted FVC of 5% (absolute) or more despite appropriate conventional therapy. Absolute change in percent predicted FVC from baseline - analyzed using a rank analysis of covariance (ANCOVA) model - will serve as efficacy-related primary study endpoint. Discussion: There is an urgent unmet clinical need for effective therapies for patients with a progressive fibrotic lung disease other than IPF. The current study protocol is unique with respect to selecting patients with different disease entities of lung fibrosis which have, however, essential pathophysiological characteristics in common. Moreover, by selecting patients with evidence of disease progression despite conventional therapy, the protocol ensures that a cohort of interstitial lung disease (ILD) patients with a high unmet medical need is targeted and it may allow a sufficiently high event rate for evaluation of treatment responses. Trial registration: DRKS00009822 (registration date: January 13th 2016)
Micrometeorological, plant-ecological, and soil-hydrological measurements in stands of spruce and beech in the Tharandt forest
This paper addresses micrometeorological, plant-ecological, and soil-hydrological measurements in stands of spruce and beech as a means to understand the processes. The long-term flux site Anchor Station Tharandt (dominated by 120-year-old spruce) shows the high dynamics of land surface- atmosphere interactions as well as the climatologically relevant effects on turbulent energy flux partitioning, carbon sequestration, and evapotranspiration (ET). Climate, phenology, and fluxes support the idea of dividing the year into an ‘active phase’ (April–September) and a ‘dormant phase’ (October–March); carbon sequestration, available energy (net radiation), and sensible heat flux are almost negligible in the dormant season. Only ET shows a significant contribution to the annual budget (25 % of the active phase) from interception (evaporation from wetted needles) driven by sensible heat flux from the atmosphere. The interannual variation of the fluxes is generally small (e. g., 500 to 650 gC m-2 yr-1 of C uptake) even for the severe drought year of 2003 (400 gC m-2) or with thinning in 2002. Compared to the beech site, the spruce site – at least in the active season – experienced similar rates of ET but smaller rates of C uptake. Canopy drip was 55 % of precipitation at the spruce site. Canopy drip (40 %) and stem flow (25 %) added up to 65 % of canopy precipitation at the beech site. This difference likely explains the generally higher soil moisture at the beech site. As a consequence of this study, models with sufficient complexity are recommended to represent the structural differences of different forest types including their phenophases. For a better representation of forests, e. g., in climate models, land surface–atmosphere interactions must be included.Diese Arbeit benutzt mikrometeorologische, pflanzenökologische und bodenhydrologische Messungen als Mittel zum Prozessverständnis. Der langfristige Flussmessstandort Ankerstation Tharandter Wald (von 120 jährigen Fichten dominiert) zeigt die große Dynamik der Landoberflächen-Atmosphären-Wechselwirkungen wie auch ihre Klimaeffekte auf die Verteilung der turbulenten Wärmeströme, die Kohlenstoffsequestrierung und die Evapotranspiration (ET). Klimawerte, Phänologie und Flüsse unterstützen die Einteilung des Jahres in eine ‚aktive Phase’ (April–September) und eine ‚Ruhephase’ (Oktober– März): Kohlenstoffsequestrierung, zur Verfügung stehende Energie (Strahlungsbilanz) und fühlbarer Wärmestrom sind in der Ruhephase praktisch vernachlässigbar. Nur ET zeigt einen signifikanten Beitrag zur Jahresbilanz (25 % der aktiven Phase) aus der Interzeption (Evaporation von benetzten Nadeln), die vom fühlbaren Wärmestrom aus der Atmosphäre angetrieben wird. Die zwischenjährliche Variation der Flüsse ist im Allgemeinen klein (z. B. 500–650 gC m-2 yr -1) C-Aufnahme), selbst mit dem starken Dürrejahr 2003 (400 gC m-2) oder dem Effekt der Durchforstung 2002. Verglichen mit der Buche erreicht die Fichte – zumindest in der aktiven Periode – ähnliche Werte von ET aber niedrigere bei der C-Aufnahme. Die Kronentraufe beträgt bei der Fichte nur ca. 55 % des Niederschlages, bei der Buche summieren sich ca. 40 % Kronentraufe und knapp 25 % Stammabfluss zu etwa 65 % Bestandesniederschlag. Dieser Unterschied erklärt möglicherweise die im Allgemeinen höhere Bodenfeuchte am Buchenstandort. Als Resultat aus dieser Arbeit werden Modelle mit ausreichender Komplexität empfohlen, welche Bestandesstruktur und Phänophasen berücksichtigen. Das ist eine Voraussetzung für eine bessere Berücksichtigung von Wäldern mit ihren Landoberflächen-
Atmosphären-Wechselwirkungen, z. B. in Klimamodellen
Teaching, Learning, and Leading with Schools and Communities: One Urban University Re-Envisions Teacher Preparation for the Next Generation
Ultimately, the national goals of improving learning outcomes for all students and reducing, if not eliminating, the achievement gap require a teaching corps that brings knowledge and professional competencies to have positive impacts on diverse learners in diverse settings (Gándara & Maxwell-Jolly, 2006). As central actors in schools, teachers have the greatest impact on student achievement (Cochran-Smith & Fries, 2005). Nevertheless, due to varied challenges of preparing high-quality teachers within the context of traditional schools of education, preparation programs have yet to consistently and comprehensively produce teachers who accomplish these outcomes (Ball & Forzani, 2009; Larabee, 2004, 2010). While substantive reform and evidence of improved teacher education emerges (Ball & Forzani, 2009, 2010; Zumwalt & Craig, 2005), systemic change that contributes to better pre-kindergarten-through-twelfth-grade (PK-12) student outcomes remains elusive (Darling-Hammond, 2010)
THE TRUST-BASED CLASSROOM: AN ANALYSIS OF CURRENT TRENDS IN SOCIAL AND EMOTIONAL LEARNING AND THE DEVELOPMENT OF A NEW TRUST-BASED APPROACH TO ART EDUCATION
Many current social and emotional learning (SEL) programs cite building trust as a key factor to an effective SEL program. Despite these references, however, they often lack an emphasis on teaching methods of building trust between students and their peers, the teacher, and the environment. Instead they focus on a specific aspect of teaching like the procedural practices of Responsive Classroom or communication and open-mindedness as in Open Circle. Explicitly building trust, however, could create an art classroom atmosphere conducive to high quality learning. This paper analyzes current trends in social and emotional learning and outlines the characteristics of the Trust-Based Classroom, an SEL program I have developed herein to address this deficit. Although creating the right environment to build trust can be difficult, recognizing, implementing, and evaluating methods of creating a trusting atmosphere, encouraging students to create individualized concentrations, emphasizing process over product, and encouraging collaboration and communication could teachers in their efforts of creating an artistic environment rich with learning. The Trust-Based Classroom focuses students on individualized, strengths-based, social and emotional learning where students and teachers alike are working to build trust between themselves and their environment
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