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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

Using earth observation-based dry season NDVI trends for assessment of changes in tree cover in the Sahel

The co-existence of trees and grasses is a defining feature of savannah ecosystems and landscapes. During recent decades, the combined effect of climate change and increased demographic pressure has led to complex vegetation changes in these ecosystems. A number of recent Earth observation (EO)-based studies reported positive changes in biological productivity in the Sahelian region in relation to

An automated field spectrometer system for studying VIS, NIR and SWIR anisotropy for semi-arid savanna

This paper presents the Dahra field spectrometer system (DAFIS) sited in Senegal, West Africa. DAFIS is a unique system that automatically measures the spectro-directional reflectance properties of a semi-arid savanna in the spectral range of 350-1800. nm, daily from sunrise to sunset. The instrumental setup allows studying surface anisotropy for different phenological phases. First data retrieved

Monitoring coal fires in Datong coalfield using multi-source remote sensing data

Numerous coal fires burn underneath the Datong coalfield because of indiscriminate mining. Landsat TM/ETM, unmanned aerial vehicle (UAV), and infrared thermal imager were employed to monitor underground coal fires in the Majiliang mining area. The thermal field distributions of this area in 2000, 2002, 2006, 2007, and 2009 were obtained using Landsat TM/ETM. The changes in the distribution were th

Human population growth offsets climate-driven increase in woody vegetation in sub-Saharan Africa

The rapidly growing human population in sub-Saharan Africa generates increasing demand for agricultural land and forest products, which presumably leads to deforestation. Conversely, a greening of African drylands has been reported, but this has been difficult to associate with changes in woody vegetation. There is thus an incomplete understanding of how woody vegetation responds to socio-economic

Elucidating the effect of additives on the alkyl chain packing of a double tail cationic surfactant

Hypothesis: Some low molecular weight additives can strongly influence the phase behavior of aqueous surfactant systems, and this offers an important handle to control the properties of surfactant solutions and thus to optimize the stability and performance of various formulations. Experiments: The surfactant dioctadecyldimethylammonium chloride (DODAC) self-assembles into two lamellar phases in w

A paradigm shift design of functional monomers for developing molecularly imprinted polymers

Functional monomers play a key role in preparing molecularly imprinted polymers (MIPs) by forming complex with templates to create recognition sites in the polymers. In this paper, a new strategy was proposed to design functional monomers for efficient MIPs synthesis. This strategy dated from the investigations on previously developed MIPs. In propranolol imprinting process, methacrylic acid has a

Robust abdominal organ segmentation using regional convolutional neural networks

A fully automatic system for abdominal organ segmentation is presented. As a first step, an organ localization is obtained via a robust and efficient feature registration method where the center of the organ is estimated together with a region of interest surrounding the center. Then, a convolutional neural network performing voxelwise classification is applied. Two convolutional neural networks o

Estimated health benefits of exhaust free transport in the city of Malmö, Southern Sweden

Air pollution is responsible for one in eight premature deaths worldwide, and thereby a major threat to human health. Health impact assessments of hypothetic changes in air pollution concentrations can be used as a mean of assessing the health impacts of policy, plans and projects, and support decision-makers in choices to prevent disease. The aim of this study was to estimate health impacts attri

Reply to Comment on 'The climate mitigation gap : Education and government recommendations miss the most effective individual actions'

In their comment piece, van Basshuysen and Brandstedt raise three main issues: first, whether population at the global scale, or individual family planning decisions, are relevant for climate change mitigation; second, they offer useful critiques of the methodologies to attribute greenhouse gas emissions for the choice to have a child; and third, they question the appropriate ethical responsibilit

IDO : Modelling a serious educational game based on hands approach for training dementia carers

Dementia is one of the burdensome diseases in older age for which there is no cure known. The demand for carers of dementia patients is growing as the population ages. We analyse serious games as an approach to provide dementia carers with training on care related problem solving and modelling real-world cases. We present the behaviour model of improved care process by applying serious games, desc

An overview of the transport of liquid molecules through structured polymer films, barriers and composites – Experiments correlated to structure-based simulations

Films engineered to control the transport of liquids are widely used through society. Examples include barriers in packaging, wound care products, and controlled release coatings in pharmaceutics. When observed at the macroscopic scale such films commonly appear homogeneous, however, a closer look reveals a complex nano- and microstructure that together with the chemical properties of the differen

Strong-coupling theory of counterions between symmetrically charged walls : From crystal to fluid phases

We study thermal equilibrium of classical pointlike counterions confined between symmetrically charged walls at distance d. At very large couplings when the counterion system is in its crystal phase, a harmonic expansion of particle deviations is made around the bilayer positions, with a free lattice parameter determined from a variational approach. For each of the two walls, the harmonic expansio

Moocar – online-kurser med global räckvidd: en lägesrapport och några lärdomar

Digitala plattformar som erbjuder så kallade Massive Open Online Courses (MOOCs) är sedan några år tillbaka ett fenomen som växt sig gradvis starkare. Moocar har lyfts fram som ett lovande exempel på tillgängliggörandet av universitetsutbildning till en bredare allmänhet och som rätt använt också har potential att nå nya studieovana målgrupper runt om på jorden. Fördelarna till trots, har utveckli