1,420 research outputs found
Qubit-portraits of qudit states and quantum correlations
The machinery of qubit-portraits of qudit states, recently presented, is
consider here in more details in order to characterize the presence of quantum
correlations in bipartite qudit states. In the tomographic representation of
quantum mechanics, Bell-like inequalities are interpreted as peculiar
properties of a family of classical joint probability distributions which
describe the quantum state of two qudits. By means of the qubit-portraits
machinery a semigroup of stochastic matrices can be associated to a given
quantum state. The violation of the CHSH inequalities is discussed in this
framework with some examples, we found that quantum correlations in qutrit
isotropic states can be detected by the suggested method while it cannot in the
case of qutrit Werner states.Comment: 12 pages, 4 figure
Stakeholder discourse and water management ? implementation of the participatory model CATCH in a Northern Italian alpine sub-catchment
International audienceThe Water Framework Directive (WFD, directive 2000/60/EC) was created to ensure the sustainable use of water resources in the European Union. A central guideline included throughout the directive is a call for the participation of stakeholders in the management of these resources. Involving stakeholders is an important step to ensure that catchment management plans take into consideration local experience in the development of these plans and the impact of the plans on local interests. This paper describes and analyses the results of a series of workshops to facilitate implementation of the WFD at a catchment level based on the stakeholder participation model, CATCH. To test the usefulness of the CATCH model, developed for water management in a catchment area, a sub-catchment in an alpine valley in the north-east of Italy, the Alta Valsugana in the Province of Trento, was chosen as the setting for a series of workshops. In this valley water is fundamental for activities associated with agriculture, domestic use, energy production, sports and recreation. In the recent past the valley has had serious problems related to water quality and quantity. Implementation of water management plans under the WFD may lead to conflicts within the catchment between different stakeholder interest groups. Including stakeholders in the development of management plans not only follows the guidelines of the WFD but also could result in a more locally adapted and acceptable plan for the catchment. A new stakeholder analysis methodology was developed and implemented in order to identify the relevant stakeholders of the area and then two sets of workshops involving the key stakeholders identified were conducted in Spring 2006. The CATCH meetings were a new experience for the participants, who had to deal with both the principles of the WFD in general and the participation requirement in particular. During the meetings, the CATCH model played a very important role in structuring the participatory process. It provided a general framework consisting of a sequence of steps that helped the participants to reach the goal of the process: the identification and evaluation of measures to improve water management in the catchment. This test of the CATCH model showed it to be a dynamic and flexible tool, useful for structuring and guiding the participation process, without imposing undue restrictions on influencing the outcome of stakeholder participation in a small catchment
Stakeholder discourse and water management in a catchment in northern Italy
International audienceThe Water Framework Directive (WFD; directive 2000/60/EC) was created to ensure the sustainable use of water resources in the European Union. A central guideline included throughout the directive is a call for the participation of stakeholders in the management of these resources. Involving stakeholders is an important step to ensure that catchment management plans take into consideration local experience in the development of these plans and the impact of the plans on local interests. This paper describes and analyses the results of a series of workshops to facilitate implementation of the WFD at a catchment level based on the stakeholder participation model, CATCH. To test the usefulness of the stakeholder participation model CATCH for water management in a catchment area, a sub-catchment in an alpine valley in the north-east of Italy, the Alta Valsugana in the Province of Trento, was chosen as the setting for a series of workshops. In this valley water is fundamental for activities associated with agriculture, domestic use, energy production, sports and recreation. In the recent past the valley has had serious problems related to water quality and quantity. Implementation of water management plans under the WFD may lead to conflicts within the catchment between different stakeholder interest groups. Including stakeholders in the development of management plans not only follows the guidelines of the WFD but also could result in a more locally adapted and acceptable plan for the catchment. A new stakeholder analysis methodology was developed and implemented in order to identify the relevant stakeholders of the area and then two sets of workshops involving the key stakeholders identified were conducted in Spring 2006. The CATCH meetings were a new experience for the participants, who had to deal with both the principles of the WFD in general and the participation requirement in particular. During the meetings, the CATCH model played a very important role in structuring the participatory process. It provided a general framework consisting of a sequence of steps that helped the participants to reach the goal of the process; the identification and evaluation of measures to improve water management in the catchment. This test of the CATCH model showed it to be a dynamic and flexible tool, useful for structuring and guiding the participation process, without imposing undue restrictions on influencing the outcome of stakeholder participation in a small catchment
Synoptic/planetary-scale interactions and blocking over the North Atlantic Ocean
Work was completed on the height tendency diagnoses of two extratropical cyclones that occurred upstream from the blocking event studied previously. One developed explosively over water 60 to 36 hours before the block first appeared, while the second developed explosively over the southeastern United States during the time of block formation. In both cases, both vorticity and temperature advection were consistently important forcing mechanisms. This is in contrast to the block itself, in which vorticity advection was easily the dominant forcing mechanism. Latent heat release was also significant, accounting for about 50 percent of the total height falls in the cyclone below 850 mb. Estimates of latent heat release were greatly enhanced by coupling parameterized estimates with values derived from GOES IR data using an algorithm developed by Marshall's F. R. Robertson. Among the difficulties encountered in this work was the identification of an appropriate lower boundary condition for the solution of the height tendency equation. The zero value currently used tends to yield underestimates of the lower troposphere height tendencies. To address this problem a new diagnostic technique was developed in cooperation with Dr. Peter Zwack of the University of Quebec at Montreal. Based on an equation Dr. Zwack had previously developed (the Zwack-Okossi development equation), researchers now have a relationship that is completely consistent with the height tendency equation and provides estimates of lower boundary geostrophic vorticity or height tendencies. Finally, comparison of the SAT (satellite data) and NOSAT (no satellite data) analyses is progressing well. The present focus is on both the new diagnostic technique and the SAT/NOSAT comparisons. The former is being tested on the southeastern United States cyclone case previously mentioned and compared with the height tendency diagnoses already completed. The latter are being examined for the blocking case described in the publications cited in this summary. In addition to obtaining statistics that will allow general comparison of the two analyses, it will be possible to determine whether conclusions about the dynamics of the block development are influenced by the analysis set used
Partial scaling transform of multiqubit states as a criterion of separability
The partial scaling transform of the density matrix for multiqubit states is
introduced to detect entanglement of quantum states. The transform contains
partial transposition as a special case. The scaling transform corresponds to
partial time scaling of subsystem (or partial Planck's constant scaling) which
was used to formulate recently separability criterion for continous variables.A
measure of entanglement which is a generalization of negativity measure is
introduced being based on tomographic probability description of spin states.Comment: 16 pages, 5 figures, submitted to J. Phys. A: Math. Ge
Susceptibility of rat retina acyl-CoA: 1-acyl-sn-glycero-3-phosphocholine O-acyltransferase and CTP:phosphocholine cytidylyltransferase activity to lipid peroxidation and hydroperoxide treatment
AbstractTwo enzyme activities involved in phospholipid metabolism in the rat retina were determined after in vivo and in vitro peroxidation according to several model systems. The in vivo models were based on: (i) intravenous administration of a sonicated emulsion of phospholipid and linoleate photooxidized mixture to normal rat for a period of one week; (ii) acute injection of Fe2+ solution (20 mM) or (iii) 0.5 mg of hydroperoxylinoleate into the vitreous body, and collection of retinal tissue 4 h or 4 days later, respectively. Oleoyl CoA:lysophosphatidylcholine acyltransferase activity was unchanged or exhibited significant inhibition. On the contrary, CTP:phosphocholine cytidylyltransferase activity was stimulated. By incubating in vitro the retina with: (i) Fe2+-ascorbate; (ii) photooxidized phospholipid mixture (0.1–5 mM) or individual phospholipid classes; (iii) hydroperoxylinoleate (0.25–2 mM), with or without Fe2+, a significant inactivation of acyltransferase (six-fold maximum loss of initial activity) and a slight stimulation of cytidylyltransferase were seen. Altogether, the results suggest that in situ oxygen radical generation by a variety of agents irreversibly perturbs enzymes and/or membrane structures in which the enzymes are inserted; these events may be a causal factor in retinal degeneration accompanying some ocular diseases
The Short and Long-term Variability of F2 or Stronger (Significant) Tornadoes in the Central Plains
An analysis of the interannual and interdecadal variability of significant tornado events that occurred over a four state region in the central plains was performed over a 53 year period (1950 - 2002) using the Storm Prediction Center (SPC) archives and simple statistical
techniques. A synoptic composite analysis using the National Centers for Environmental
Prediction (NCEP) - National Center for Atmospheric Research (NCAR) re-analyses was
performed in order to determine whether there was support for the statistical relationships through the large-scale composite dynamics. The results showed that when the 53 year raw annual tornado occurrences are used, there was no statistically significant El Nino-related
variability, and El Nino years produced slightly more tornado occurrences. However, when annual tornado occurrences were examined across different phases of the Pacific Decadal Oscillation, there was a likely tendency for more tornado occurrences in El Nino years during PDO2 and no significant interannual variability during PDO1 years. During the 1950 - 1976 period, other studies have found that significant tornado occurrences were overestimated. When
a simple correction factor was applied here and the interannual variability re-examined, the strength of the statistical relationships changed such that there was now a likely tendency for fewer tornado occurrences in El Nino years during the PDO1 period, and no statistically significant relationship for PDO2 years. Finally an examination of the composite dynamics
during the bulk of tornado season revealed that, out of five years examined, the large-scale flows were of similar dynamic character for four of them. The season which produced the most tornadoes qualitatively was shown to be slightly more conducive to severe weather production when using simple empirical severe weather indexes
Investigating the game-related statistics and tactical profile in NCAA division I men's basketball games
Technical and tactical aspects in Italian youth rugby union in relation to different academies, regional tournaments, and outcomes
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