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Satellite passive microwaves reveal recent climate-induced carbon losses in African drylands

The African continent is facing one of the driest periods in the past three decades as well as continued deforestation. These disturbances threaten vegetation carbon (C) stocks and highlight the need for improved capabilities of monitoring large-scale aboveground carbon stock dynamics. Here we use a satellite dataset based on vegetation optical depth derived from low-frequency passive microwaves (

Soil and vegetation-atmosphere exchange of NO, NH3, and N2O from field measurements in a semi arid grazed ecosystem in Senegal

The alternating between dry and wet seasons and the consecutive microbial responses to soil water content in semiarid ecosystems has significant consequences on nitrogen exchanges with the atmosphere. Three field campaigns were carried out in a semi arid sahelian rangeland in Dahra (Ferlo, Senegal), two at the beginning of the wet season in July 2012 and July 2013, and the third one in November 20

Snow cover and snow albedo changes in the central Andes of Chile and Argentina from daily MODIS observations (2000–2016)

The variables of snow cover extent (SCE), snow cover duration (SCD), and snow albedo (SAL) are primary factors determining the surface energy balance and hydrological response of the cryosphere, influencing snow pack and glacier mass-balance, melt, and runoff conditions. This study examines spatiotemporal patterns and trends in SCE, SCD, and SAL (2000–2016; 16 years) for central Chilean and Argent

Woody plant cover estimation in drylands from Earth Observation based seasonal metrics

From in situ measured woody cover we develop a phenology driven model to estimate the canopy cover of woody species in the Sahelian drylands at 1km scale. The model estimates the total canopy cover of all woody phanerophytes and the concept is based on the significant difference in phenophases of dryland trees, shrubs and bushes as compared to that of the herbaceous plants. Whereas annual herbaceo

Remote sensing of vegetation dynamics in drylands : Evaluating vegetation optical depth (VOD) using AVHRR NDVI and in situ green biomass data over West African Sahel

Monitoring long-term biomass dynamics in drylands is of great importance for many environmental applications including land degradation and global carbon cycle modeling. Biomass has extensively been estimated based on the normalized difference vegetation index (NDVI) as a measure of the vegetation greenness. The vegetation optical depth (VOD) derived from satellite passive microwave observations i

Assessing woody vegetation trends in Sahelian drylands using MODIS based seasonal metrics

Woody plants play a major role for the resilience of drylands and in peoples' livelihoods. However, due to their scattered distribution, quantifying and monitoring woody cover over space and time is challenging. We develop a phenology driven model and train/validate MODIS (MCD43A4, 500 m) derived metrics with 178 ground observations from Niger, Senegal and Mali to estimate woody cover trends from

Global-scale mapping of changes in ecosystem functioning from earth observation-based trends in total and recurrent vegetation

Aim: To evaluate trend analysis of earth observation (EO) dense time series as a new way of describing and mapping changes in ecosystem functioning at regional to global scales. Spatio-temporal patterns of change covering 1982-2011 are discussed in the context of changes in land use and land cover (LULCC). Location: Global. Methods: This study takes advantage of the different phenological cycles o

Lévy-stable two-pion Bose-Einstein correlations in s NN =200 GeV Au+Au collisions

We present a detailed measurement of charged two-pion correlation functions in 0-30% centrality sNN=200 GeV Au+Au collisions by the PHENIX experiment at the Relativistic Heavy Ion Collider. The data are well described by Bose-Einstein correlation functions stemming from Lévy-stable source distributions. Using a fine transverse momentum binning, we extract the correlation strength parameter λ, the

Open Notes in Swedish Psychiatric Care (Part 2) : Survey Among Psychiatric Care Professionals

Background: This is the second of two papers presenting the results from a study of the implementation of patient online access to their electronic health records (here referred to as Open Notes) in adult psychiatric care in Sweden. The study contributes an important understanding of both the expectations and concerns that existed among health care professionals before the introduction of the Open

Test of Responsiveness and Sensitivity of the Questionnaire "lymphedema Quality of Life Inventory"

Background: Lymphedema may affect patients' health-related quality of life (HRQoL) and thus a disease-specific questionnaire is needed. The Lymphedema Quality of life Inventory (LyQLI) has been tested for reliability and validity. The purpose of this study was to test the LyQLI for responsiveness and sensitivity. Methods and Results: The study participants were patients with lymphedema in the uppe

Astrometry and exoplanets in the Gaia era : A Bayesian approach to detection and parameter recovery

The Gaia mission is expected to make a significant contribution to the knowledge of exoplanet systems, both in terms of their number and of their physical properties. We develop Bayesian methods and detection criteria for orbital fitting, and revise the detectability of exoplanets in light of the in-flight properties of Gaia. Limiting ourselves to one-planet systems as a first step of the developm

Coding variants in NOD-like receptors : An association study on risk and survival of colorectal cancer

Nod-like receptors (NLRs) are important innate pattern recognition receptors and regulators of inflammation or play a role during development. We systematically analysed 41 non-synonymous single nucleotide polymorphisms (SNPs) in 21 NLR genes in a Czech discovery cohort of sporadic colorectal cancer (CRC) (1237 cases, 787 controls) for their association with CRC risk and survival. Five SNPs were f

Cultural diversity and employment growth : Moderating effect of the recent global financial crisis

This article analyses the effect of cultural diversity on employment growth, considering the recent global financial crisis (GFC) as a moderating factor. In doing so, we developed competing hypotheses based on Blau’s theory of heterogeneity versus an alternative perspective which combines the resource-based view (RBV) with social identity theory (SIT). We empirically test such theories using a uni

Dental ecometrics of tropical Africa : Linking vegetation types and communities of large plant-eating mammals

Background: The dental characteristics of large plant-eating mammals, such as hypsodonty, quite accurately describe present and past climatic conditions worldwide. However, several peculiar regions give systematically higher predictions of primary productivity than the local average environmental conditions should support. We call these 'anomalies'. Anomalies are prominent in areas dominated by pa

A versatile velocity map ion-electron covariance imaging spectrometer for high-intensity XUV experiments

We report on the design and performance of a velocity map imaging (VMI) spectrometer optimized for experiments using high-intensity extreme ultraviolet (XUV) sources such as laser-driven high-order harmonic generation (HHG) sources and free-electron lasers (FELs). Typically exhibiting low repetition rates and high single-shot count rates, such experiments do not easily lend themselves to coinciden