85 research outputs found
SAFE - a Tool for Assessing the Sustainability of Agricultural Systems: an Illustration
SAFE (Framework for Assessing Sustainability levels) is a tool for evaluating the sustainability of agricultural systems and uses a hierarchical framework populated with indicators objectively selected by multicriteria evaluation. Indicators are measured at field, farm and landscape scales and progressively integrated into a global sustainability index (SI). SAFE is illustrated below with results on a field scale from a farm site
SAFE: A Framework for Assessing Sustainability Levels in Agricultural Systems
Evaluating the sustainability of agricultural systems is a major challenge for scientists, policy makers and farmers. Numerous sets of indicators have recently been designed, both at national and international levels. However, most of these initiatives focus only on environmental aspects of sustainability, indicators are often selected arbitrarily and usually do not fit in a consistent, comprehensive and universally applicable framework. This paper presents an original framework for integrating the information contained by indicators into a single quantitative measure of agricultural sustainability in order to facilitate comparison and diagnosis
Dew-worms in white nights: High-latitude light constrains earthworm (Lumbricus terrestris) behaviour at the soil surface
Soil is an effective barrier to light penetration that limits the direct influence of light on belowground organisms. Variation in aboveground light conditions, however, is important to soil-dwelling animals that are periodically active on the soil surface. A prime example is the earthworm Lumbricus terrestris L. (the dew-worm), an ecosystem engineer that emerges nocturnally on the soil surface. In the summer, the northernmost populations of L. terrestris are exposed to a time interval with no daily dark period. During a two-week period preceding the summer solstice, we studied the constraints that boreal night illumination imposes on L. terrestris surface activity by comparing their behaviour under ambient light with artificially-induced darkness. Looking for evidence of geographical divergence in light response, we compared the behaviour of native L. terrestris (Jokioinen, S–W Finland; 60°48′N) with two markedly more southern populations, from Preston (Lancashire, UK; 53°47′N) and Coshocton (Ohio, USA; 40°22′N) where the nights have a period of darkness throughout the year (total latitudinal range ca. 2300 km). Under ambient light conditions, L. terrestris emergence on the soil surface was diminished by half compared with the darkened treatment and it peaked at the darkest period of the night. Also mating rate decreased considerably under ambient light. The native dew-worms were generally the most active under ambient light. They emerged earlier in the evening and ceased their activity later in the morning than dew-worms from the two more southerly populations. The differences in behaviour were, however, significant mainly between native and UK dew-worms. In the darkened treatment, the behaviour of the three earthworm origins did not differ. Under the experimental conditions light condition was the dominant environmental factor controlling surface activity, but elevated night-time air temperature and humidity also encouraged dew-worm emergence without discernible differences among geographical origins. Our results show, that in boreal summer, the high level of night illumination strongly limits soil-surface activity of dew-worms. Considering the important regulatory role of L. terrestris in many ecosystem processes, this can have significant corollaries in dew-worm impacts on the environment. Although evidence for geographical differentiation in behaviour was obtained, the results point to phenotypic flexibility in L. terrestris light response
Idiopathische Normale Druk Hydrocephalie en de oudere patiënt
Idiopathische Normal Pressure Hydrocephalus (iNPH) wordt gekenmerkt door de
trias cognitieve stoornissen, loopstoornissen en urine-incontinentie. De behandeling
bestaat uit het plaatsen van een ventriculoperitoneale drain. Onder meer door verschillende
onderzoeksmethoden in trials met mogelijk meerdere biasvormen, maar
ook eventueel bijkomende neurodegeneratieve aandoeningen, zoals de Ziekte van
Alzheimer en vasculaire dementie, zijn er geen goede kwantitatieve noch kwalitatieve
gegevens die de lange termijn resultaten van een drain voorspellen. Omdat deze
co-morbiditeit medebepalend is of de verwachte winst van een drain opweegt tegen
de complicatiekans, is een kritische multidisciplinaire analyse van de co-morbiditeit,
kwetsbaarheid én wens van de patiënt voorwaardelijk om te komen tot klinische relevante
meerwaarde
Maturation-Dependent Licensing of Naive T Cells for Rapid TNF Production
The peripheral naïve T cell pool is comprised of a heterogeneous population of cells at various stages of development, which is a process that begins in the thymus and is completed after a post-thymic maturation phase in the periphery. One hallmark of naïve T cells in secondary lymphoid organs is their unique ability to produce TNF rapidly after activation and prior to acquiring other effector functions. To determine how maturation influences the licensing of naïve T cells to produce TNF, we compared cytokine profiles of CD4+ and CD8+ single positive (SP) thymocytes, recent thymic emigrants (RTEs) and mature-naïve (MN) T cells during TCR activation. SP thymocytes exhibited a poor ability to produce TNF when compared to splenic T cells despite expressing similar TCR levels and possessing comparable activation kinetics (upregulation of CD25 and CD69). Provision of optimal antigen presenting cells from the spleen did not fully enable SP thymocytes to produce TNF, suggesting an intrinsic defect in their ability to produce TNF efficiently. Using a thymocyte adoptive transfer model, we demonstrate that the ability of T cells to produce TNF increases progressively with time in the periphery as a function of their maturation state. RTEs that were identified in NG-BAC transgenic mice by the expression of GFP showed a significantly enhanced ability to express TNF relative to SP thymocytes but not to the extent of fully MN T cells. Together, these findings suggest that TNF expression by naïve T cells is regulated via a gradual licensing process that requires functional maturation in peripheral lymphoid organs
Is Financial Market Volatility Informative to Predict Recessions?
It is commonly agreed that the term spread and stock returns are useful in predicting recessions. We investigate whether interest rate
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