931 research outputs found
Aging dynamics of +-J Edwards-Anderson spin glasses
We analyze by means of extensive computer simulations the out of equilibrium
dynamics of Edwards-Anderson spin glasses in d=4 and d=6 dimensions with +-J
interactions. In particular, we focus our analysis on the scaling properties of
the two-time autocorrelation function in a range of temperatures from T=0.07
T_c to T=0.75 T_c in both systems. We observe that the aging dynamics of the
+-J models is different from that observed in the corresponding Gaussian
models. In both the 4d and 6d models at very low temperatures we study the
effects of discretization of energy levels. Strong interrupted aging behaviors
are found. We argue that this is because in the times accessible to our
simulations the systems are only able to probe activated dynamics through the
lowest discrete energy levels and remain trapped around nearly flat regions of
the energy landscape. For temperatures T >= 0.5 T_c in 4d we find logarithmic
scalings that are compatible with dynamical ultrametricity, while in 6d the
relaxation can also be described by super-aging scalings.Comment: 7 pages, 10 figure
Organic and Mineral Fertilisation of Temporary Grassland
In Italy, the need to reduce the application of chemical fertilisers and to dispose of different kinds of bio-wastes (municipal solid waste (MSW), olive mill waste, distiller\u27s grains) has led to more compost being made from these materials. Since 1995 our Institute has carried out several studies on different crops. The results obtained so far for grain and industrial crops (Montemurro et al., 2003; Maiorana et al., 2004) appear very interesting. But rarely have the composts been applied to fodder crops. Therefore, this research is aimed to evaluate the effect of MSW-compost on temporary grassland of cocksfoot (Dactylis glomerata) and of lucerne, (Medicago sativa) in Southern Italy (Apulia Region)
Dynamics and nonequilibrium states in the Hamiltonian mean-field model: A closer look
We critically revisit the evidence for the existence of quasistationary
states in the globally coupled XY (or Hamiltonian mean-field) model. A
slow-relaxation regime at long times is clearly revealed by numerical
realizations of the model, but no traces of quasistationarity are found during
the earlier stages of the evolution. We point out the nonergodic properties of
this system in the short-time range, which makes a standard statistical
description unsuitable. New aspects of the evolution during the nonergodic
regime, and of the energy distribution function in the final approach to
equilibrium, are disclosed
Vinorelbine-based salvage therapy in HER2-positive metastatic breast cancer patients progressing during trastuzumab-containing regimens: a retrospective study
<p>Abstract</p> <p>Background</p> <p>The vinka-alkaloyd vinorelbine is a potentially valuable treatment in patients with HER2-positive, trastuzumab-resistant advanced breast cancer. We sought to document the clinical activity of vinorelbine-based salvage treatments in this clinical setting.</p> <p>Methods</p> <p>We analyzed a cohort of 424 consecutive women receiving trastuzumab-based therapy for HER2-positive advanced breast cancer. Of these, 299 were identified as progressing during the initial trastuzumab-based treatment, and 77 received vinorelbine-based therapy as first salvage treatment. Central review of pathological specimens revealed that 70 patients had HER2-amplification detected by FISH. For these patients we determined overall response rate (ORR = complete-CR + partial-PR) and clinical benefit (CB = CR+PR+ Stable disease lasting at least 6 months), time to progression (TTP) and overall survival (OS) from the initiation of vinorelbine-based salvage therapy.</p> <p>Results</p> <p>In 60 patients who were evaluable for tumor response, ORR and CB rates were 28% (95% C.I. 18%-41%) and 50% (95% C.I. 38%-62%), respectively. Median follow-up from the initiation of salvage therapy was 15 months (range 1–63 months). Median TTP and OS were 7.1 months (95% C.I. 6.6–7.7 months) and 21 months (95% C.I. 14.3–27.7 months), respectively. No differences in clinical outcomes were observed according to whether vinorelbine was administered as a single agent or in combination with other cytostatics, or whether trastuzumab was stopped or continued beyond disease progression.</p> <p>Conclusion</p> <p>our findings suggests that vinorelbine-based combinations are active and should be further evaluated in studies conducted in trastuzumab-resistant patients, including those evaluating newer HER2-targeting agents.</p
Suspended InAs nanowire Josephson junctions assembled via dielectrophoresis
We present a novel technique for the realization of suspended Josephson junctions based on InAs semiconductor nanowires. The devices are assembled using a technique of drop-casting guided by dielectrophoresis, which allows one to finely align the nanostructures on top of the electrodes. The proposed architecture removes the interaction between the nanowire and the substrate which is known to influence disorder and the orientation of the Rashba vector. The relevance of this approach in view of the implementation of hybrid Josephson junctions based on semiconducting nanowires coupled with high-temperature superconductors is discussed
Environmental and economic assessment of sustainability in Mediterranean wheat production
ArticleThis study proposes the application of the Life Cycle Assessment (LCA) and economic
evaluations conducted on different cereal production systems in semi-arid environments. Two
different crop management systems of durum wheat were analysed by distinguishing Continuous
Cropping (CC) and Crop Rotation (CR) with vetch, that are conducted through two different
levels of crop intensification (in terms of tillage and fertilization strategies): Conventional (Conv)
and Conservative (Cons). The resulting four scenarios were examined using LCA methodology
to assess the environmental impacts, and the Production Cost (PC) analysis to estimate the
economic results. Overall, the findings of this research provide an opportunity to identify
sustainable crops management strategies
ISOLATION AND GENOTYPING OF AEROMONAS SPP. IN READY-TO-EAT FOODS. PRELIMINARY RESULTS
The taxonomy of the genus Aeromonas is constantly changing and it is important that strains are identified and carefully differentiate. The aim of this preliminary investigation was to assess the presence of Aeromonas spp. in RTE foods from supermarkets and sushi Take Away and stored at refrigeration temperature. Particular attention was given to the choice of culture media in order to assess their ability to differentiate Aeromonas spp. and to perform subsequent phylogenetic analysis and the characterization of the species isolated
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