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New satellite-based estimates show significant trends in spring phenology and complex sensitivities to temperature and precipitation at northern European latitudes

Recent climate warming has altered plant phenology at northern European latitudes, but conclusions regarding the spatial patterns of phenological change and relationships with climate are still challenging as quantitative estimates are strongly diverging. To generate consistent estimates of broad-scale spatially continuous spring plant phenology at northern European latitudes (> 50° N) from 2000

Increased mortality in non-alcoholic fatty liver disease with chronic kidney disease is explained by metabolic comorbidities

Background: There is a close association between non-alcoholic fatty liver disease (NAFLD) and prevalent chronic kidney disease (CKD). Few longitudinal studies exist. No previous study has investigated to what extent CKD affects mortality in biopsy-proven NAFLD. Our aim was to investigate the long-term risk of developing CKD in biopsy-proven NAFLD and its effect on mortality. Methods: Patients wi

Wild-caught great tits Parus major fail to use tools in a laboratory experiment, despite facilitation

Studies investigating tool use in animals that are not known tool users in the wild are important in helping to understand how and under what circumstances this ability might arise. Tool use appears to be uncommon in great tits (Parus major), with only a single documented observation in which a wild great tit used conifer needles to extract larvae from crevices in trees. In a laboratory-based expe

What future for primates? Conservation struggles in the forests of Cross River State, Nigeria

While deforestation and forest degradation have gained attention in recent years not least at the UN climate negotiations, a third “de”, i.e., defaunation, has to a great extent been overlooked. Human-induced faunal loss does not only reduce tree species diversity, but also significantly erodes key ecosystem services and functions and further disadvantages local communities. In this article, we an

The Preparation of Decellularized Mouse Lung Matrix Scaffolds for Analysis of Lung Regenerative Cell Potential

Lung transplantation is the only option for patients with end-stage lung disease, but there is a shortage of available lung donors. Furthermore, efficiency of lung transplantation has been limited due to primary graft dysfunction. Recent mouse models mimicking lung disease in humans have allowed for deepening our understanding of disease pathomechanisms. Moreover, new techniques such as decellular

Computed electronic and optical properties of SnO2 under compressive stress

We consider the effects of three different types of applied compressive stress on the structural, electronic and optical properties of rutile SnO2. We use standard density functional theory (DFT) to determine the structural parameters. The effective masses and the electronic band gap, as well as their stress derivatives, are computed within both DFT and many-body perturbation theory (MBPT). The st

10Be and Cosmogenic Radionuclides in Ice Cores

This article summarizes the processes that are responsible for cosmogenic radionuclide variations in ice cores and the results that can be inferred from these records. The article starts with the production in the atmosphere caused by the influx of galactic cosmic ray particles and its modulation by the solar and geomagnetic fields. Subsequently, the geochemical behavior of cosmogenic radionuclide

Quasiparticle electronic structure of barium-silicon oxynitrides for white-LED application

Ba3Si6O12N2:Eu2+ and Ba3Si6O9N4:Eu2+ have strikingly similar atomistic structures, but the former is an efficient green phosphor at working temperature while the latter is a bluish-green phosphor whose luminescence decreases quite fast with temperature. Aiming at the understanding of such different behavior, we compute the quasiparticle electronic band structure of the two hosts, Ba3Si6O 12N2 and

Band widths and gaps from the Tran-Blaha functional : Comparison with many-body perturbation theory

For a set of ten crystalline materials (oxides and semiconductors), we compute the electronic band structures using the Tran-Blaha (TB09) functional. The band widths and gaps are compared with those from the local-density approximation (LDA) functional, many-body perturbation theory (MBPT), and experiments. At the density-functional theory (DFT) level, TB09 leads to band gaps in much better agreem

Climate-fire interactions and Savanna ecosystems : A dynamic vegetation modeling study for the African Continent

Savannas are inherently “disturbed” ecosystems, but the regularly recurring disruptions play such a fundamental ecological role (Scholes and Archer, 1997) that “episodic events” rather than “disturbance” may the more apt terminology. From an atmospheric perspective, fire is the most significant of these episodic events. Fires shape community species composition; tree to grass ratio and nutrient re

Electronic properties of interfaces and defects from many-body perturbation theory : Recent developments and applications

We review some recent developments in many-body perturbation theory (MBPT) calculations that have enabled the study of interfaces and defects. Starting from the theoretical basis of MBPT, Hedin's equations are presented, leading to the GW and GWΓ approximations. We introduce the perturbative approach, that is the one most commonly used for obtaining quasiparticle (QP) energies. The practical strat

G0W0 band gap of ZnO : Effects of plasmon-pole models

Carefully converged calculations are performed for the band gap of ZnO within many-body perturbation theory (G0W0 approximation). The results obtained using four different well-established plasmon-pole models are compared with those of explicit calculations without such models (the contour-deformation approach). This comparison shows that, surprisingly, plasmon-pole models depending on the f-sum r

GW approximations and vertex corrections on the Keldysh time-loop contour : Application for model systems at equilibrium

We study the effects of self-consistency and vertex corrections on different GW-based approximations for model systems of interacting electrons. For dealing with the most general case, we use the Keldysh time-loop contour formalism to evaluate the single-particle Green's functions. We provide the formal extension of Hedin's GW equations for the Green's function in the Keldysh formalism. We show an

Theoretical approach for white-LED Phosphors : From crystal structures to optical properties

Some theoretical approaches are reviewed to analyze crystallographic and optical properties of phosphors for white light emitting diodes. Stresses are placed on 1) local electro-neutrality for the structural stability of hosts, and 2) dielectric property and coordination of anion ligands around rare-earth luminescent centre for the tuning of emission colour. First-principles calculation results ar

Vertex corrections in localized and extended systems

Within many-body perturbation theory, we apply vertex corrections to various closed-shell atoms and to jellium, using a local approximation for the vertex consistent with starting the many-body perturbation theory from a Kohn-Sham Green's function constructed from density-functional theory in the local-density approximation. The vertex appears in two places-in the screened Coulomb interaction W an

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This article discusses the position of Southern Yemen with Stockholm's Negotiation, that this talks between two parties, the government and the Houthi Rebel, while the Southern case far from this dialougue.

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This article analyzes how political parties in Yemen work to create slogans and use them to gain power

Dynamic protein changes in the perihaemorrhagic zone of Surgically Treated Intracerebral Haemorrhage Patients

The secondary injury cascades exacerbating the initial brain injury following intracerebral haemorrhage (ICH) are incompletely understood. We used dual microdialysis (MD) catheters placed in the perihaemorrhagic zone (PHZ) and in seemingly normal cortex (SNX) at time of surgical ICH evacuation in ten patients (range 26-70 years). Routine interstitial MD markers (including glucose and the lactate/p