Modeling of the particle scattering structure factor for branched bio-polymers in solution: A X-ray scattering study

We present a study which illustrates the modeling of the Particle Scattering Structure Factor from Small Angle X-ray Scattering (SAXS) data. The studied sample was a poly(amidoamine) Pamam dendrimers in water solution. The intra-particle form factor P(q) has been analyzed employing an inverse Fourier transformation which allows to obtain the particle pair distance distribution function and to gain information about dendrimer shape. The experimental inter-dendrimer structure factor S(q) has been analysed in the framework of liquid integral equation theory for charged systems in solution. From that, we derive an effective interparticle interaction composed of a screened Coulombic plus hard-sphere repulsion potential, which allow the estimation of the dendrimer effective surface charge Zeff. The present analysis, applied to a Pamam dendrimers in water solution, strongly supports the finding that structures and interaction of dendrimer is strongly influenced by charge effects. As a result, this quantity can be considered as a crucial parameters for the modulation of the degree of structural organization in solution, suitable for a number of potential applications

Antibodies to Lipopolysaccharides after Immunization of Humans with the Rough Mutant Escherichia coli J5

To investigate whether immunization with Escherichia coli J5 boiled cells induces antibodies directed at deep core structures, antibodies against JS lipopolysaccharide (LPS), Re LPSt and Iipid A were measured in the serum of 70 volunteers before and 2 weeks after immunization. To improve the sensitivity and the specificity ofELISAt complexes of core LPS with high-density lipoproteins were used instead of free core LPS as antigens. A median three-fold increase in antibodies directed against J5 LPS was observed, but no significant increase in the antibodies against Re LPS or lipid A was found. Since JS antiserum did not react with several smooth LPS or with Re LPS and lipid At cross-reactivity could not be demonstrated. Thus, immunization of volunteers with E. coli J5 produced a modest specific antibody response against J5 LPS. The mechanism of protection previously observed with J5 antiserum remains unclea

Rapporto energia 2013: monitoraggio sull’energia in Sicilia

L’obiettivo della politica energetica europea è quello di abbassare le emissioni di CO2 e di operare una trasformazione del sistema che privilegi un'economia a basse emissioni di carbonio ed estremamente efficiente sotto il profilo energetico. A tal fine, l’U.E. ha allungato l’orizzonte temporale entro cui raggiungere questi virtuosi risultati e, con il Libro verde della Commissione «Un quadro per le politiche dell'energia e del clima all'orizzonte 2030», del 27 marzo 2013, ha aperto una consultazione sulle modalità con cui coniugare il soddisfacimento della sempre più crescente domanda di energia con le necessità di riduzione dei gas inquinanti e di fornitura di energia a prezzi contenuti, data l’attuale fase di crisi economica e finanziaria. I pilastri della politica energetica dell'U.E. sono la sostenibilità, la sicurezza dell'approvvigionamento e la competitività, elementi che, dapprima, hanno orientato la definizione del Pacchetto Clima 2020 (i cui obiettivi sono la riduzione del 20% delle emissioni inquinanti, la riduzione del 20% dei consumi finali energia prodotta da fonti rinnovabili, e l’incremento del 20% dell’efficienza energetica), e che ora ispirano la nuova strategia elaborata dalla Commissione europea per il post 2020 e contenuta nell’Energy Roadmap 2050. In aderenza al nuovo orizzonte temporale preso in considerazione dalla politica energetica europea, anche quella nazionale si prefigge il raggiungimento ed il superamento degli obiettivi del Pacchetto Clima-Energia 2020. Successivamente alla consultazione pubblica effettuata nel periodo compreso tra il 16 ottobre ed il 30 novembre 2012, con D.M. 8 marzo 2013, è stato approvato, il documento contenente la Strategia Energetica Nazionale (S.E.N.), che esplicita l’impegno italiano al raggiungimento, entro il 2050, dell’obiettivo di decabornizzazione dell’economia fissato dalla politica energetica europea. La Strategia enuclea quattro finalità principali che devono ispirare le azioni da intraprendere nel settore energetico: 1) ridurre significativamente il gap di costo dell’energia per i consumatori e le imprese, allineando prezzi e costi dell’energia a quelli europei al 2020, e assicurando che la transizione energetica di più lungo periodo (2030-2050) non comprometta la competitività industriale italiana ed europea; 2) raggiungere e superare gli obiettivi ambientali e di decarbonizzazione definiti dal Pacchetto europeo Clima-Energia 2020, ed assumere un ruolo guida nella definizione ed implementazione della Roadmap 2050; 3) continuare a migliorare la nostra sicurezza ed indipendenza di approvvigionamento; 4) Favorire la crescita economica sostenibile attraverso lo sviluppo del settore energetico. Dalla realizzazione delle iniziative previste nella S.E.N., si prevede di conseguire una progressiva e significativa trasformazione del sistema, dal punto di vista sia economico sia ambientale

AI and blockchain as new triggers in the education arena

Several scholars have examined the potential use of AI and Blockchain in education, primarily focusing on the contributions of such technologies with a goal to improve learning possibilities and outcomes for students. Such technologies may be utilized to ensure that all students have equal access to education, including people with disabilities, refugees, and those living in isolated communities or rural areas. AI-empowered applications such as holograms and robotics may enable children with special needs to attend school from home or from hospital, as well as ensure learning continuity in emergencies or crises, such as during the recent COVID pandemic. Moreover, teachers and lecturers can utilize such new systems to monitor asynchronous discussion groups, boosting the involvement of the participants through Intelligent Tutoring Systems, making group discussions more engaging even at a distance, coupled with e-learning. In larger cohorts, AI can support the fast grading of tests and homework and can provide tools to prevent cheating.info:eu-repo/semantics/publishedVersio

From antiferromagnetism to d-wave superconductivity in the 2D t-J model

We have found that the two dimensional t-J model, for the physical parameter range J/t = 0.4 reproduces the main experimental qualitative features of High-Tc copper oxide superconductors: d-wave superconducting correlations are strongly enhanced upon small doping and clear evidence of off diagonal long range order is found at the optimal doping \delta ~ 0.15. On the other hand antiferromagnetic long range order, clearly present at zero hole doping, is suppressed at small hole density with clear absence of antiferromagnetism at \delta >~ 0.1.Comment: 4 pages, 5 figure

Charge fluctuations close to phase separation in the two dimensional t-J model

We have studied the t-J model using the Green Function Monte Carlo technique. We have obtained accurate energies well converged in the thermodynamic limit, by performing simulations up to 242 lattice sites. By studying the energy as a function of hole doping we conclude that there is no phase separation in the physical region, relevant for HTc superconductors. This finding is further supported by the hole-hole correlation function calculation. Remarkably, by approaching the phase separation instability, for $J_c/t\sim 0.5$,this function displays enhanced fluctuations at incommensurate wavevectors, scaling linearly with the doping, in agreement with experimental findings.Comment: To appear on Phys. Rev. Let