237 research outputs found
Stilbenes as constitutive and induced protection compounds in Scots pine (Pinus sylvestris L.)
More-than-Human Dynamics of Inequality in the Governance of Pandemic Threats : Intersectionality, Social Positionings, and the Nonhuman during the 2014 Ebola Outbreak
In responding to ongoing viral outbreak emergencies, decision-makers constantly face the need to deploy governance measures to meet uncertain scenarios. One of the key aspects of such work is to identify different sources of threat, assess the risk that they pose, and to act in consequence. In this paper, we aim to direct attention toward ways in which science-based international governance practices reproduce various social inequalities by enacting social divisions based on categorizations into the threatening and the worthy of protection. We propose that these practices are usefully approached from the perspective we label more-than-human intersectionality and illustrate this with examples from the 2014 Ebola outbreak. More specifically, we argue that adopting a more-than-human intersectional approach importantly sheds light on connections between outbreak response and inequalities in global health that both precede and emerge in governance practices that provide unequally distributed access to care and protection. Furthermore, we claim that this approach extends our understanding of the role played by nonhuman actors in global health policy and the necessity to pay attention to how those nonhumans motivate specific paths for outbreak response that intersect with social positionings and subsequent dynamics of marginalization and oppression.Peer reviewe
Molecular ordering of precursor films during spreading of tiny liquid droplets
In this work we address a novel feature of spreading dynamics of tiny liquid
droplets on solid surfaces, namely the case where the ends of the molecules
feel different interactions to the surface. We consider a simple model of
dimers and short chain--like molecules which cannot form chemical bonds with
the surface. We study the spreading dynamics by Molecular Dynamics techniques.
In particular, we examine the microscopic structure of the time--dependent
precursor film and find that in some cases it can exhibit a high degree of
local order. This order persists even for flexible chains. Our results suggest
the possibility of extracting information about molecular interactions from the
structure of the precursor film.Comment: 4 pages, revtex, no figures, complete file available from
ftp://rock.helsinki.fi/pub/preprints/tft/ or at
http://www.physics.helsinki.fi/tft/tft_preprints.html (to appear in Phys.
Rev. E Rapid Comm.
Scavenging of ultrafine particles by rainfall at a boreal site: observations and model estimations
International audienceValues of the scavenging coefficient were determined from observations of ultrafine particles (with diameters in the range 10?510 nm) during rain events at a boreal forest site in Southern Finland between 1996 and 2001. The estimated range of values of the scavenging coefficient was [7Ă10?6?4Ă10?5] s?1, which is generally higher than model calculations based only on below-cloud processes (Brownian diffusion, interception, and typical charge effects). A new model that includes below-cloud scavenging processes, mixing of ultrafine particles from the boundary layer (BL) into cloud, followed by cloud condensation nuclei activation and in-cloud removal by rainfall, is presented. The effective scavenging coefficients estimated from this new model have values comparable with those obtained from observations. Results show that ultrafine particle removal by rain depends on aerosol size, rainfall intensity, mixing processes between BL and cloud elements, in-cloud scavenged fraction, in-cloud collection efficiency, and in-cloud coagulation with cloud droplets. Implications for the treatment of scavenging of BL ultrafine particles in numerical models are discussed
Selection of raw material for a demanding wooden façade and the quality control of timber from harvesting to construction site
Effects of intensified silviculture on timber production and its economic profitability in boreal Norway spruce and Scots pine stands under changing climatic conditions
201
Global warming will affect the maximum potential abundance of boreal plant species
Forecasting the impact of future global warming on biodiversity requires understanding how temperature limits the distribution of species. Here we rely on Liebig's Law of Minimum to estimate the effect of temperature on the maximum potential abundance that a species can attain at a certain location. We develop 95%âquantile regressions to model the influence of effective temperature sum on the maximum potential abundance of 25 common understory plant species of Finland, along 868 nationwide plots sampled in 1985. Fifteen of these species showed a significant response to temperature sum that was consistent in temperatureâonly models and in allâpredictors models, which also included cumulative precipitation, soil texture, soil fertility, tree species and stand maturity as predictors. For species with significant and consistent responses to temperature, we forecasted potential shifts in abundance for the period 2041â2070 under the IPCC A1B emission scenario using temperatureâonly models. We predict major potential changes in abundance and average northward distribution shifts of 6â8âkmâyrâ1. Our results emphasize interâspecific differences in the impact of global warming on the understory layer of boreal forests. Species in all functional groups from dwarf shrubs, herbs and grasses to bryophytes and lichens showed significant responses to temperature, while temperature did not limit the abundance of 10 species. We discuss the interest of modelling the âmaximum potential abundanceâ to deal with the uncertainty in the predictions of realized abundances associated to the effect of environmental factors not accounted for and to dispersal limitations of species, among others. We believe this concept has a promising and unexplored potential to forecast the impact of specific drivers of global change under future scenarios.202
Dynamics of Spreading of Chainlike Molecules with Asymmetric Surface Interactions
In this work we study the spreading dynamics of tiny liquid droplets on solid
surfaces in the case where the ends of the molecules feel different
interactions with respect to the surface. We consider a simple model of dimers
and short chainlike molecules that cannot form chemical bonds with the surface.
We use constant temperature Molecular Dynamics techniques to examine in detail
the microscopic structure of the time dependent precursor film. We find that in
some cases it can exhibit a high degree of local order that can persist even
for flexible chains. Our model also reproduces the experimentally observed
early and late-time spreading regimes where the radius of the film grows
proportional to the square root of time. The ratios of the associated transport
coefficients are in good overall agreement with experiments. Our density
profiles are also in good agreement with measurements on the spreading of
molecules on hydrophobic surfaces.Comment: 12 pages, LaTeX with APS macros, 21 figures available by contacting
[email protected], to appear in Phys. Rev.
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