70 research outputs found
Water for cities: The impact of climate change and demographic growth in the tropical Andes
[1] Globally, water resources for cities are under increasing stress. Two main stressors are climate change and population growth, but evaluating their relative impact is difficult, especially because of the complex topology of water supply. This is especially true in the tropical Andes, which is a region with strong climatic gradients and topographical limits to water resources. This paper presents an evaluation of both stressors on water resources in a geospatial framework to identify gradients in water availability that may lead to conflicts over water use. We focus on four major cities in, or receiving water from, the tropical Andes. A multimodel data set of 19 climate models is used as input for a regional water balance model. Per capita water availability is evaluated along topographic gradients for the present and for future scenarios of population growth and climate change. In all cases, the median projection of climate change suggests a relatively limited impact on water availability, but uncertainties are large. Despite these uncertainties, we find that the expected demographic changes are very likely to outpace the impact of climate change on water availability and should therefore be the priority for local policy making. However, distinctive geospatial patterns characterize the supply systems of the studied cities, highlighting the need to analyze the topology of water supply within an ecosystem services context. Our approach is flexible enough to be extended to other regions, stressors and water resources topologies. Citation: Buytaert, W., and B. De Bièvre (2012), Water for cities: The impact of climate change and demographic growth in th
Measuring nonclassicality of bosonic field quantum states via operator ordering sensitivity
We introduce a new distance-based measure for the nonclassicality of the
states of a bosonic field, which outperforms the existing such measures in
several ways. We define for that purpose the operator ordering sensitivity of
the state which evaluates the sensitivity to operator ordering of the Renyi
entropy of its quasi-probabilities and which measures the oscillations in its
Wigner function. Through a sharp control on the operator ordering sensitivity
of classical states we obtain a precise geometric image of their location in
the density matrix space allowing us to introduce a distance-based measure of
nonclassicality. We analyse the link between this nonclassicality measure and a
recently introduced quantum macroscopicity measure, showing how the two notions
are distinct
Simultaneous quantization of edge and bulk Hall conductivity
The edge Hall conductivity is shown to be an integer multiple of
which is almost surely independent of the choice of the disordered
configuration. Its equality to the bulk Hall conductivity given by the
Kubo-Chern formula follows from K-theoretic arguments. This leads to
quantization of the Hall conductance for any redistribution of the current in
the sample. It is argued that in experiments at most a few percent of the total
current can be carried by edge states.Comment: 6 pages Latex, 1 figur
A first search of excited states double beta and double electron capture decays of Pd110 and Pd102
A search for double beta decays of the palladium isotopes 110Pd and 102Pd
into excited states of their daughters was performed and first half-life limits
for the 2{\nu}{\beta}{\beta} and 0{\nu}{\beta}{\beta} decays into first excited
0+ and 2+ states of 5.89e19 yr and 4.40e19 yr (95% CL) for the 110Pd decay were
obtained. The half-life limits for the corresponding double electron capture
transition of 102Pd are 7.64e18 yr and 2.68e18 yr (95% CL) respectively. These
are the first measurements for 102Pd.Comment: Updated to published version. Refined analysis and minor text
changes. Half-life limits change
Occurrence of entomopathogenic fungi in soils in Southern Italy
The natural occurrence of entomopathogenic fungi was investigated in Southern Italian soils using larvae of Galleria mellonella L. (Lepidoptera: Galleriidae) as “bait insect”. Since September (1996) to March (1997) 188 samples of soil were collected from different habitats (woodland, orchard, field, seacoast, grassland, uncultivated land and salt pan). Parasitic fungi were obtained from 14.9% of the soil samples. There were 3 entomopathogenic species: Metarhizium anisopliae (Metchnikoff) Sorokin, Paecilomyces lilacinus (Thom) Samson and Beauveria bassiana (Balsamo) Vuillemin. The most common fungal pathogen was B. bassiana. Both M. anisopliae and P. lilaci- nus were isolated only once. The occurrence of B. bassiana seems to be affected by the soil type and the habitat. Key words: survey, Beauveria bassiana, Metarhizium anisopliae, Paecilomyces lilacinus. FUNGHI ENTOMOPATOGENI NEI TERRENI DELL’ITALIA MERIDIONALE È stata effettuata un’indagine per valutare la presenza e la distribuzione di funghi entomopatogeni nei terreni dell’Italia meridionale utilizzando larve di Galleria mellonella L. (Lepidoptera: Galleriidae) come insetto esca. Da settembre 1996 a marzo 1997, sono stati esaminati 188 cam- pioni di terreno provenienti da diversi biotopi. Sono state rinvenute larve infettate da funghi in 28 campioni (14,9%) e sono state identificate 10 specie di funghi parassiti di cui 3 propriamente entomopatogeni: Metarhizium anisopliae (Metchnikoff) Sorokin, Paecilomyces lilacinus (Thom) Samson e Beauveria bassiana (Balsamo) Vuillemin. Il fungo patogeno rinvenuto con maggior frequenza è risultato essere B. bassiana. La sua presenza sembra correlata alle caratteristiche del suolo e dell’habitat. Parole chiave: indagine, Beauveria bassiana, Metarhizium anisopliae, Paecilomyces lilacinus
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