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Multi-model evaluation of the sensitivity of the global energy budget and hydrological cycle to resolution
This study undertakes a multi-model comparison with the aim to describe and quantify systematic changes of the global energy and water budgets when the horizontal resolution of atmospheric models is increased and to identify common factors of these changes among models. To do so, we analyse an ensemble of twelve atmosphere-only and six coupled GCMs, with different model formulations and with resolutions spanning those of state-of-the-art coupled GCMs, i.e. from resolutions coarser than 100 km to resolutions finer than 25 km. The main changes in the global energy budget with resolution are a systematic increase in outgoing longwave radiation and decrease in outgoing shortwave radiation due to changes in cloud properties, and a systematic increase in surface latent heat flux; when resolution is increased from 100 to 25 km, the magnitude of the change of those fluxes can be as large as 5 W m−2. Moreover, all but one atmosphere-only model simulate a decrease of the poleward energy transport at higher resolution, mainly explained by a reduction of the equator-to-pole tropospheric temperature gradient. Regarding hydrological processes, our results are the following: (1) there is an increase of global precipitation with increasing resolution in all models (up to 40 × 103 km3 year−1) but the partitioning between land and ocean varies among models; (2) the fraction of total precipitation that falls on land is on average 10% larger at higher resolution in grid point models, but it is smaller at higher resolution in spectral models; (3) grid points models simulate an increase of the fraction of land precipitation due to moisture convergence twice as large as in spectral models; (4) grid point models, which have a better resolved orography, show an increase of orographic precipitation of up to 13 × 103 km3 year−1 which explains most of the change in land precipitation; (5) at the regional scale, precipitation pattern and amplitude are improved with increased resolution due to a better simulated seasonal mean circulation. We discuss our results against several observational estimates of the Earth's energy budget and hydrological cycle and show that they support recent high estimates of global precipitation
Investigating the Host Binding Signature on the Plasmodium falciparum PfEMP1 Protein Family
The Plasmodium falciparum erythrocyte membrane protein 1
(PfEMP1) family plays a central role in antigenic variation and cytoadhesion of
P. falciparum infected erythrocytes. PfEMP1
proteins/var genes are classified into three main
subfamilies (UpsA, UpsB, and UpsC) that are hypothesized to have different roles
in binding and disease. To investigate whether these subfamilies have diverged
in binding specificity and test if binding could be predicted by adhesion domain
classification, we generated a panel of 19 parasite lines that primarily
expressed a single dominant var transcript and assayed binding
against 12 known host receptors. By limited dilution cloning, only UpsB and UpsC
var genes were isolated, indicating that UpsA
var gene expression is rare under in vitro
culture conditions. Consequently, three UpsA variants were obtained by rosette
purification and selection with specific monoclonal antibodies to create a more
representative panel. Binding assays showed that CD36 was the most common
adhesion partner of the parasite panel, followed by ICAM-1 and TSP-1, and that
CD36 and ICAM-1 binding variants were highly predicted by adhesion domain
sequence classification. Binding to other host receptors, including CSA, VCAM-1,
HABP1, CD31/PECAM, E-selectin, Endoglin, CHO receptor “X”, and
Fractalkine, was rare or absent. Our findings identify a category of larger
PfEMP1 proteins that are under dual selection for ICAM-1 and CD36 binding. They
also support that the UpsA group, in contrast to UpsB and UpsC
var genes, has diverged from binding to the major
microvasculature receptor CD36 and likely uses other mechanisms to sequester in
the microvasculature. These results demonstrate that CD36 and ICAM-1 have left
strong signatures of selection on the PfEMP1 family that can be detected by
adhesion domain sequence classification and have implications for how this
family of proteins is specializing to exploit hosts with varying levels of
anti-malaria immunity
Genome-wide meta-analysis identifies five new susceptibility loci for cutaneous malignant melanoma.
Thirteen common susceptibility loci have been reproducibly associated with cutaneous malignant melanoma (CMM). We report the results of an international 2-stage meta-analysis of CMM genome-wide association studies (GWAS). This meta-analysis combines 11 GWAS (5 previously unpublished) and a further three stage 2 data sets, totaling 15,990 CMM cases and 26,409 controls. Five loci not previously associated with CMM risk reached genome-wide significance (P < 5 × 10(-8)), as did 2 previously reported but unreplicated loci and all 13 established loci. Newly associated SNPs fall within putative melanocyte regulatory elements, and bioinformatic and expression quantitative trait locus (eQTL) data highlight candidate genes in the associated regions, including one involved in telomere biology.[Please see the Supplementary Note for acknowledgments.]This is the author accepted manuscript. The final version is available from NPG via http://dx.doi.org/10.1038/ng.337
Consensus guidelines for the use and interpretation of angiogenesis assays
The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference
Ultrafast energy transfer between lipid-linked chromophores and plant light-harvesting complex II
We characterize the photophysical interactions between lipid-linked chromophores and plant light-harvesting proteins incorporated into nanodiscs using optical spectroscopy, simulations and theoretical modelling.</jats:p