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A climate-change risk analysis for world ecosystems

We quantify the risks of climate-induced changes in key ecosystem processes during the 21st century by forcing a dynamic global vegetation model with multiple scenarios from 16 climate models and mapping the proportions of model runs showing forest/nonforest shifts or exceedance of natural variability in wildfire frequency and freshwater supply. Our analysis does not assign probabilities to scenar

Remarks on the use of 13C and 18O isotopes in Atmospheric CO2 to Quantify biospheric carbon fluxes

This chapter uses the mass-conservation equations for CO2 and its isotopomers 13CO2 and CO18O that can be used to infer globally biospheric and oceanic net fluxes in the case of 18C, and gross terrestrial biospheric fluxes in the case of 18O. The quantitative use of atmospheric measurements of 13C and 18O in CO2 to better constrain those fluxes requires knowledge of various processes specific to e

An example of an automatic differentiation-based modelling system

We present a prototype of a Carbon Cycle Data Assimilation System (CCDAS), which is composed of a terrestrial biosphere model (BETHY) coupled to an atmospheric transport model (TM2), corresponding derivative codes and a derivative-based optimisation routine. In calibration mode, we use first and second derivatives to estimate model parameters and their uncertainties from atmospheric observations a

Two decades of terrestrial carbon fluxes from a carbon cycle data assimilation system (CCDAS)

This paper presents the space-time distribution of terrestrial carbon fluxes for the period 1979-1999 generated by a terrestrial carbon cycle data assimilation system (CCDAS). CCDAS is based around the Biosphere Energy Transfer Hydrology model. We assimilate satellite observations of photosynthetically active radiation and atmospheric CO2 concentration observations in a two-step process. The contr

Constraining temperature variations over the last millennium by comparing simulated and observed atmospheric CO2

The response of atmospheric CO2 and climate to the reconstructed variability in solar irradiance and radiative forcing by volcanoes over the last millennium is examined by applying a coupled physical-biogeochemical climate model that includes the Lund-Potsdam-Jena dynamic global vegetation model (LPJ-DGVM) and a simplified analogue of a coupled atmosphere-ocean general circulation model. The model

Modelling terrestrial vegetation dynamics and carbon cycling for an abrupt climatic change event

Abrupt climatic changes have occurred several times in the past, leading to large-scale modifications of vegetation patterns with important consequences for the global carbon cycle. Dynamic global vegetation models (DGVM) constitute an advanced tool for reconstructing past or predicting future shifts in vegetation distributions in response to climatic change on a global scale. The Lund-Potsdam-Jen

Simulating near-equilibrium climate and vegetation for 6000 cal. years BP

The response of a coupled atmosphere-ocean general circulation model to insolation representative of 6000 years ago has been studied with a set of 1000-year quasi-equilibrium simulations. Comparison with similar experiments with an uncoupled atmosphere general circulation model demonstrates the importance of an interactive ocean for the climate signal. The model simulates an intensification of the

Climate and interannual variability of the atmosphere-biosphere 13CO2 flux

We present a bottom-up approach to simulate the terrestriál isotopic carbon variations using the Lund-Postsdam-Jena dynamic global vegetation model (LPJ-DGVM). LPJ is extended to include isotopic fractionation of 13C at the leaf level during assimilation and includes a full isotopic terrestrial carbon cycle. The model thus allows a quantitative analysis of the net biosphere exchange of CO2 and 13C

Implications of ice core smoothing for inferring CO2 flux variability

Ice core records are commonly used to infer information about past variability of CO2 fluxes. Because of processes involved in enclosing this air in ice, ice core records are a smoothed representation of the actual past atmospheric variations. As such, there is a limit to how much information ice core measurements can contain about flux variability on short timescales. With a numerical model of th

Att förstå Kinas nutida militära strategier

Bokanmälan av (1) Peter Mattis: Analyzing the Chinese Military. A Review Essay and Resource Guide on the People’s Liberation Army [2015] och (2) Joe McReynolds (red): China’s Evolving Military Strategy [2016]

Spatial location and emotion modulate voice perception

How do we perceive voices coming from different spatial locations, and how is this affected by emotion? The current study probed the interplay between space and emotion during voice perception. Thirty participants listened to nonverbal vocalizations coming from different locations around the head (left vs. right; front vs. back), and differing in valence (neutral, positive [amusement] or negative

Degrowth through Income and Wealth Caps?

In the degrowth literature, maximum caps on wealth and/or income are frequently mentioned among the policy instruments that could support transitions towards ecologically and socially sustainable societies. Yet an in-depth discussion of concrete policy proposals has yet to be initiated. To facilitate such a discussion, the present paper reviews several proposals for placing caps on wealth and/or i

Fetal and neonatal alloimmune thrombocytopenia : recommendations for evidence-based practice, an international approach

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) may result in severe bleeding, particularly fetal and neonatal intracranial haemorrhage (ICH). As a result, FNAIT requires prompt identification and treatment; subsequent pregnancies need close surveillance and management. An international panel convened to develop evidence-based recommendations for diagnosis and management of FNAIT. A rigorou

An Act for the Abolition of the Slave Trade : The effects of an import ban on Cape Colony slaveholders

Few could have foreseen the consequences when the British Parliament, in 1807, passed the Slave Trade Act that sought to abolish slave imports into the British Empire. From population decreases in the British Caribbean to increased prices in the Cape Colony, historical evidence suggests that the effects of the Act were felt far and wide even though commercialization of slaves was still possible wi

Effects of phosphorus in growth media on biomineralization and cell surface properties of marine cyanobacteria synechococcus

Through geological time, cyanobacterial picoplankton have impacted the global carbon cycle by sequestrating CO 2 and forming authigenic carbonate minerals. Various studies have emphasized the cyanobacterial cell envelopes as nucleation sites for calcium carbonate formation. Little is known, however, about how environmental conditions (e.g., nutrient content) trigger a cell surface and its proper

IL-16/miR-125a axis controls neutrophil recruitment in pristane-induced lung inflammation

Severe lung inflammation and alveolar hemorrhage can be life-threatening in systemic lupus erythematosus (SLE) patients if not treated early and aggressively. Neutrophil influx is the driver key of this pathology, but little is known regarding the molecular events regulating this recruitment. Here, we uncover a role for IL-16/mir-125a in this pathology and show not only that IL-16 is a target for

Mechanical and structural characterization of cast iron using synchrotron light

The paper describes work done using synchrotron light to investigate the microstructure and how it behaves in 3D when a load is applied. Two different cast iron materials with different matrix structures and graphite morphologies were investigated; SiMo51, which is basically a spheroidal iron (SGI) alloyed with Si and Mo, and a lamellar graphite iron (LGI). The tensile test specimens were loaded i

A method of predicting the in vitro fibril formation propensity of Aβ40 mutants based on their inclusion body levels in E. coli

Overexpression of recombinant proteins in bacteria may lead to their aggregation and deposition in inclusion bodies. Since the conformational properties of proteins in inclusion bodies exhibit many of the characteristics typical of amyloid fibrils. Based on these findings, we hypothesize that the rate at which proteins form amyloid fibrils may be predicted from their propensity to form inclusion b

Genome wide analysis for mouth ulcers identifies associations at immune regulatory loci

Mouth ulcers are the most common ulcerative condition and encompass several clinical diagnoses, including recurrent aphthous stomatitis (RAS). Despite previous evidence for heritability, it is not clear which specific genetic loci are implicated in RAS. In this genome-wide association study (n = 461,106) heritability is estimated at 8.2% (95% CI: 6.4%, 9.9%). This study finds 97 variants which alt