30 results match your criteria: "International Institute of Applied Systems Analysis[Affiliation]"

Isotopic pulse-labelling of photosynthate allows tracing of carbon (C) from tree canopies to belowground biota and calculations of its turnover in roots and recipient soil microorganisms. A high concentration of label is desirable, but is difficult to achieve in field studies of intact ecosystem patches with trees. Moreover, root systems of trees overlap considerably in most forests, which requires a large labelled area to minimize the impact of C allocated belowground by un-labelled trees.

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Climate change is projected to have substantial economic, social, and environmental impacts worldwide. Currently, the leading solutions for hydrogen storage are in salt caverns, and depleted natural gas reservoirs. However, the required geological formations are limited to certain regions.

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Sustainable water management is essential to increasing water availability and decreasing water pollution. The wastewater sector is expanding globally and beginning to incorporate technologies that recover nutrients from wastewater. Nutrient recovery increases energy consumption but may reduce the demand for nutrients from virgin sources.

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Article Synopsis
  • Many vertebrate species around the world, like mammals and birds, are seeing their populations decline a lot.
  • This study looks at how human activities, like pollution and farming, indirectly affect these species by harming their food sources and other interactions in the ecosystem.
  • The research found that two big threats, direct exploitation (like hunting) and agricultural practices, are putting a huge number of species and their relationships at risk in Europe.
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Immunity-driven evolution of virulence and diversity in respiratory diseases.

Evolution

November 2023

Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Koper, Slovenia.

The time-honored paradigm in the theory of virulence evolution assumes a positive relation between infectivity and harmfulness. However, the etiology of respiratory diseases yields a negative relation, with diseases of the lower respiratory tract being less infective and more harmful. We explore the evolutionary consequences in a simple model incorporating cross-immunity between disease strains that diminishes with their distance in the respiratory tract, assuming that docking rate follows the match between the local mix of cell surface types and the pathogen's surface and cross-immunity the similarity of the pathogens' surfaces.

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Global red and processed meat trade and non-communicable diseases.

BMJ Glob Health

November 2021

Center for Systems Integration and Sustainability, Michigan State University, East Lansing, Michigan, USA.

Introduction: Rapid increases in the trade of global red and processed meat impede international efforts toward sustainable diets by increasing meat consumption. However, little research has examined cross-country variations in diet-related non-communicable diseases (NCDs) because of meat trade. We aimed to examine the impact of red and processed meat trade on diet-related NCDs and to identify which countries are particularly vulnerable to diet-related NCDs due to red and processed meat trade.

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Correction to: Finite dimensional state representation of physiologically structured populations.

J Math Biol

September 2020

Mathematical Institute and Institute of Biology, Leiden University, 2333 CA, Leiden, The Netherlands.

In the original publication of the article, the Subsection 2.1.2 was published incorrectly.

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Groundwater provides critical freshwater supply, particularly in dry regions where surface water availability is limited. Climate change impacts on GWS (groundwater storage) could affect the sustainability of freshwater resources. Here, we used a fully-coupled climate model to investigate GWS changes over seven critical aquifers identified as significantly distressed by satellite observations.

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By conventional measures, it is often remarked that Central and South America is one of the fastest aging geographic regions in the world. In recent years, however, scholars have sought to problematize the orthodox measures and concepts employed in the aging literature. By not taking dynamic changes in life expectancy into account, measures which hold chronological age constant (e.

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Seasonal mismatches between electricity supply and demand is increasing due to expanded use of wind, solar and hydropower resources, which in turn raises the interest on low-cost seasonal energy storage options. Seasonal pumped hydropower storage (SPHS) can provide long-term energy storage at a relatively low-cost and co-benefits in the form of freshwater storage capacity. We present the first estimate of the global assessment of SPHS potential, using a novel plant-siting methodology based on high-resolution topographical and hydrological data.

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Finite dimensional state representation of physiologically structured populations.

J Math Biol

January 2020

Mathematical Institute and Institute of Biology, Leiden University, 2333 CA, Leiden, The Netherlands.

In a physiologically structured population model (PSPM) individuals are characterised by continuous variables, like age and size, collectively called their i-state. The world in which these individuals live is characterised by another set of variables, collectively called the environmental condition. The model consists of submodels for (i) the dynamics of the i-state, e.

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On models of physiologically structured populations and their reduction to ordinary differential equations.

J Math Biol

January 2020

Mathematical Institute and Institute of Biology, Leiden University, 2333 CA, Leiden, The Netherlands.

Considering the environmental condition as a given function of time, we formulate a physiologically structured population model as a linear non-autonomous integral equation for the, in general distributed, population level birth rate. We take this renewal equation as the starting point for addressing the following question: When does a physiologically structured population model allow reduction to an ODE without loss of relevant information? We formulate a precise condition for models in which the state of individuals changes deterministically, that is, according to an ODE. Specialising to a one-dimensional individual state, like size, we present various sufficient conditions in terms of individual growth-, death-, and reproduction rates, giving special attention to cell fission into two equal parts and to the catalogue derived in an other paper of ours (submitted).

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Biological invasions have emerged as an eminent feature of global change, with substantial impacts on the environment and human livelihoods. Current research demonstrates that the numbers and impacts of alien species are rising unabatedly. At the same time, we lack a thorough understanding of potential future trajectories for the decades to come.

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This study presents detailed analysis of spatiotemporal variations and trend of dust optical properties i.e., Aerosol Optical Depth (AOD) and Angstrom component over Asian desert regions using thirteen years of data (i.

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Remoteness promotes biological invasions on islands worldwide.

Proc Natl Acad Sci U S A

September 2018

Division of Conservation Biology, Vegetation and Landscape Ecology, University of Vienna, 1030 Vienna, Austria.

One of the best-known general patterns in island biogeography is the species-isolation relationship (SIR), a decrease in the number of native species with increasing island isolation that is linked to lower rates of natural dispersal and colonization on remote oceanic islands. However, during recent centuries, the anthropogenic introduction of alien species has increasingly gained importance and altered the composition and richness of island species pools. We analyzed a large dataset for alien and native plants, ants, reptiles, mammals, and birds on 257 (sub) tropical islands, and showed that, except for birds, the number of naturalized alien species increases with isolation for all taxa, a pattern that is opposite to the negative SIR of native species.

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Beyond R Maximisation: On Pathogen Evolution and Environmental Dimensions.

Trends Ecol Evol

June 2018

Evolution and Ecology Program, International Institute of Applied Systems Analysis, A-2361 Laxenburg, Austria; Mathematical Institute & Institute of Biology, Leiden University, P.O. Box 9512, 2300RA Leiden, The Netherlands; Netherlands Centre for Biodiversity, Naturalis, P.O. Box 9517, 2300RA Leiden, The Netherlands.

A widespread tenet is that evolution of pathogens maximises their basic reproduction ratio, R. The breakdown of this principle is typically discussed as exception. Here, we argue that a radically different stance is needed, based on evolutionarily stable strategy (ESS) arguments that take account of the 'dimension of the environmental feedback loop'.

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Lakes and reservoirs affect the timing and magnitude of streamflow, and are therefore essential hydrological model components, especially in the context of global flood forecasting. However, the parameterization of lake and reservoir routines on a global scale is subject to considerable uncertainty due to lack of information on lake hydrographic characteristics and reservoir operating rules. In this study we estimated the effect of lakes and reservoirs on global daily streamflow simulations of a spatially-distributed LISFLOOD hydrological model.

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Integrating remotely sensed surface water extent into continental scale hydrology.

J Hydrol (Amst)

December 2016

European Commission, Joint Research Centre, Ispra, Italy; Utrecht University, Faculty of Geosciences, Utrecht, The Netherlands.

In hydrological forecasting, data assimilation techniques are employed to improve estimates of initial conditions to update incorrect model states with observational data. However, the limited availability of continuous and up-to-date ground streamflow data is one of the main constraints for large-scale flood forecasting models. This is the first study that assess the impact of assimilating daily remotely sensed surface water extent at a 0.

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Over the last two decades evolutionary branching has emerged as a possible mathematical paradigm for explaining the origination of phenotypic diversity. Although branching is well understood for one-dimensional trait spaces, a similarly detailed understanding for higher dimensional trait spaces is sadly lacking. This note aims at getting a research program of the ground leading to such an understanding.

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Extreme droughts, heat waves, frosts, precipitation, wind storms and other climate extremes may impact the structure, composition and functioning of terrestrial ecosystems, and thus carbon cycling and its feedbacks to the climate system. Yet, the interconnected avenues through which climate extremes drive ecological and physiological processes and alter the carbon balance are poorly understood. Here, we review the literature on carbon cycle relevant responses of ecosystems to extreme climatic events.

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Article Synopsis
  • The study investigates how environmental and human activities affect the maturation traits of Alaskan sockeye salmon, noting that the size of spawning adults has decreased over time, despite stable age composition.
  • Researchers used a long-term dataset to analyze maturation reaction norms in nine fish populations and found that size-selective fishing has likely contributed to smaller maturation sizes in most populations.
  • The findings indicate that both ocean changes and adaptive microevolution could explain the observed life-history changes, highlighting the importance of considering evolutionary factors for sustainable resource management.
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Recent estimates of additional land available for bioenergy production range from 320 to 1411 million ha. These estimates were generated from four scenarios regarding the types of land suitable for bioenergy production using coarse-resolution inputs of soil productivity, slope, climate, and land cover. In this paper, these maps of land availability were assessed using high-resolution satellite imagery.

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We consider the interaction between a general size-structured consumer population and an unstructured resource. We show that stability properties and bifurcation phenomena can be understood in terms of solutions of a system of two delay equations (a renewal equation for the consumer population birth rate coupled to a delay differential equation for the resource concentration). As many results for such systems are available (Diekmann et al.

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