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A multicenter surveillance study was performed to determine the rates of hand carriage of potential pathogens among healthcare personnel in four neonatal intensive care units. Staphylococcus aureus, enterococci, and gram-negative bacilli were recovered from 8%, 3%, and 2% of 1000 hand culture samples, respectively.

A low-power prototype of neutron amplifier, based on a 70 MeV, high current proton cyclotron being installed at LNL for the SPES RIB facility, was recently proposed within INFN-E project. This prototype uses a thick Beryllium converter to produce a fast neutron spectrum feeding a sub-critical reactor core. To complete the design of such facility the new measurement of neutron yield from a thick Beryllium target was performed at LNS. This measurement used liquid scintillator detectors to identify produced neutrons by Pulse Shape Discrimination and Time of Flight technique to measure neutron energy in the range 0.5-62 MeV. To extend the covered neutron energy range He3 detector was used to measure neutrons below 0.5 MeV. The obtained yields were normalized to the charge deposited by the proton beam on the metallic Beryllium target. These techniques allowed to achieve a wide angular coverage from 0 to 150 degrees and to explore almost complete neutron energy interval., To appear in proceedings of ANIMMA International Conference, June 23-27, Marseille, France

Isospin transport phenomena in dissipative heavy ion collisions have been in- vestigated at Fermi energies with a beam of 84 Kr at 35AMeV. A comparison of theh Ni /Z of light and medium products forward-emitted in the centre of mass frame when the beam impinges on two different targets, the n-poor 112 Sn and the n-rich 124 Sn, is presented. Data were collected by means of a three-layer telescope with very good performances in terms of mass identification (full isotopic resolution up to Z�20 for ions punching through the first detector layer) built by the FAZIA Collaboration and located just beyond the grazing angle for both reactions. Theh Ni /Z of the products detected when the n-rich target is used is always higher than that associated to the n-poor one; since the detector was able to measure only fragments coming from the QuasiProjectile decay and/or neck emission, the observed behaviour can be ascribed to the isospin diffusion process, driven by the isospin gradient between QuasiProjectile and QuasiTarget. Moreover, for light fragments theh Ni /Z as a function of the lab velocity of the fragment is observed to increase when we move from the QuasiProjectile velocity to the centre of mass (neck zone). This effect can be interpreted as an evidence of isospin drift driven by the density gradient between the QuasiProjectile zone (at normal density) and the more diluted neck zone.

C. PARASCANDOLO, D. PIERROUTSAKOU, C. AGODI, R. ALBA, V. BARAN, A. BOIANO, M. COLONNA, R. CONIGLIONE, E. DE FILIPPO, A. DEL ZOPPO, M. DI TORO, U. EMANUELE, F. FARINON, A. GUGLIELMETTI , M. LA COMMARA, C. MAIOLINO, B. MARTIN, M. MAZZOCCO, C. MAZZOCCHI , C. RIZZO, M. ROMOLI, D. SANTONOCITO, C. SIGNORINI, R. SILVESTRI, F. SORAMEL, E. STRANO, D. TORRESI, A. TRIFIRO AND M. TRIMARCHI a Dip. di Fisica e Astronomia, Universita di Padova and INFN, Sezione di Padova

The teaching in biomaterials topics encloses a great number of subject related with different branch of the science. It is very accepted nowadays that the use of modern educational programs with the employ of computational techniques is an excellent way to increases the illustrative, didactic and instructive power of the almost all of maters. The current learning platforms facilitate the development of student’s professional abilities too. This work is about the implementation process of the novel Moodle biomaterials courses designed for students of Biomedical Engineering Degree. It was established Moodle courses in each Cuban educational center involucrated in this effort (Las Villas University and Orient University) and also was established another one course for distance learning with complementary materials at the “Aula en Red” of University of Havana. The primary results indicated a great student’s satisfaction and an important improvement of the learning process at the biomaterials field.

EXCYT, a project for a low energy ISOL facility at LNS, has been funded. It is based on two already existing particle accelerators. A K = 800 superconducting cyclotron will deliver the primary beam of ions A ≤ 48, E = 50–80 MeV/amu. After its interaction in a thick target, the negatively ionized radioactive products (A < 80) will be post-accelerated to 0.2–8 MeV/amu by a 15MV SMP tandem. A description of the facility, including the fully redesigned ion optics, an overview of the design problems and the expected secondary beam intensities are presented.

We report on the results of experiments performed to investigate the 58 Ni+ 58 Ni 30 MeV/nucleon reaction. In midperipheral collisions a massive fragment (4⩽ Z ⩽12) production has been observed. The emission patterns exhibit features consistent with dynamical fragmentation of a neck zone between the interacting nuclei, while in addition and at the same time, the projectile-like and target-like residues are subject to statistical decay. The nature of the fragments produced via the two different mechanisms differ both for what concerns charge distribution and isotopic composition. In particular, neutron rich fragments can be produced in dynamical processes, even if the starting nuclear matter presents a N / Z ratio close to the unity.

Expérience GANIL, MEDEA; We investigate experimentally the issue of selecting classes of multiple particle decay events in nucleus-nucleus collisions at intermediate energy taking into account the fluctuations of global observables. We show that observed binomial-like multiplicity distributions do not necessarily imply evidence of reducibility to an elementary binary emission probability.

Gamma-rays emitted from hot nuclei of mass around 115 and excitation energies above 300 MeV, formed in the 36 Ar + 90 Zr at 27 MeV/u, 36 Ar + 94 Zr at 32 MeV/u and 36 Ar + 98 Mo at 37 MeV/u, have been measured with the MEDEA multidetector in coincidence with evaporation residues. The γ-ray yield from the decay of the Giant Dipole Resonance is independent of excitation energy and of bombarding energy.

The reaction dynamics has been investigated in the 58Ni+58Ni at 30 MeV/u reaction studying energetic proton emission and heavy residue features. Moreover, measuring the hard gamma multiplicity associated to different classes of heavy residues we achieve a quantitative measurement of the reaction centrality. Experimental data have been also compared with dynamical calculations. Protons with energy exceeding more than five times the incident energy per nucleon were measured and their impact parameter dependence seems to indicate the presence of cooperative processes.

The energetic proton emission has been investigated as a function of the reaction centrality for the system 58Ni + 58Ni at 30A MeV. Extremely energetic protons (EpNN > 130 MeV) were measured and their multiplicity is found to increase almost quadratically with the number of participant nucleons thus indicating the onset of a mechanism beyond one and two-body dynamics., 5 pages, 2 figures, submitted to Physical Review Letters

La infeccion por Strongyloides stercoralis puede ocasionar sintomas parecidos al asma, pero su mecanismo de produccion no se ha esclarecido. Un campesino de 55 anos de edad, con enfermedad de dos anos de evolucion diagnosticada como asma y tratada sin exito con broncodilatadores y corticoides, fue enviado a nuestro hospital por disnea grave. La radiografia inicial de torax mostro leve atrapamiento aereo y las pruebas de funcion pulmonar detectaron obstruccion de las vias aereas que no mejoro con salbutamol. La broncoscopia revelo multiples nodulos que se proyectaban hacia la luz de las vias aereas. En el lavado broncoalveolar y en las heces se identificaron larvas de S. stercoralis. Se inicio tratamiento con albendazol, pero en los siguientes tres dias el estado de salud del paciente empeoro, presento hemoptisis y, finalmente, fallecio. La autopsia demostro larvas de Strongyloides dentro de los nodulos bronquiales. La infeccion por S. stercoralis debe considerarse en el diagnostico diferencial de sintomas asmatiformes refractarios al tratamiento, y en estos casos la produccion de nodulos podria ser el mecanismo de obstruccion.

A new organocatalytic cascade reaction for obtaining spiropyrazolones with four chiral centers is developed.

Heavy ion reactions induced by few tens MeV/nucleon beams constitute an ideal framework for producing and studying nuclear excited states close to the decay threshold. The fragmentation of quasi-projectiles from the nuclear reaction 40Ca+12C at 25 MeV/nucleon performed at LNS-Catania was employed in order to populate the Hoyle state of 12C and investigate the theoretically predicted molecular structures. Complete kinematic characterization of individual decay events, made possible by the CHIMERA high-granularity 4π charged particle multi-detector, reveals that 7.5±4.0% of the particle decays of the Hoyle state correspond to direct decays in three equal-energy α-particles and thus fulfill the decay criteria of an α-particle condensate. Moreover, events with increased kinetic energy dispersion in the 12C center of mass, which amount to 9.5±4.0%, point toward the occurrence of a second competing molecular configuration, a linear α-chain type. Both α-particle condensate and linear chain structures have been theoretically predicted but, to our knowledge, not experimentally confirmed so far.

The multiparticle decay in collisions induced by 44 MeV/nucleon $^{40}\mathrm{Ar}$ and $^{132}\mathrm{Xe}$ projectiles on several targets is studied using MEDEA 4\ensuremath{\pi} detection system. The impact parameter dependence of the charged particle multiplicity is determined. The dependence is strong in peripheral and midcentral collisions and becomes weaker in central collisions. The prediction of a molecular dynamics simulation is in agreement with the experiment.

An exclusive study of the hard photon production in the reaction $^{40}\mathrm{Ar}$+$^{51}\mathrm{V}$ at 44 MeV/nucleon has been carried on with the $4\ensuremath{\pi}$ multidetector MEDEA. An anticorrelation effect in the emission of very energetic photons and protons has been observed for the first time. This is a strong indication for the first-chance $n\ensuremath{-}p$ bremsstrahlung production mechanism.

The event-by-event determination of the impact parameter from particle multiplicity emitted in heavy-ion collisions is considered. The associate problem of the determination of the particle multiplicity on both multi-event and event-by-event basis is formulated and discussed. It is shown that a multi-event data analysis procedure allows an accurate determination of the multipolicity distribution of the emitted particles even with not necessarily large total efficiency and granularity detection systems. In the event-by-event data analysis procedure a fold-to-multiplicity conversion based on the Bayes strategy is adopted. It is shown that a reliable event-by-event multiplicity determination and multiplicity resolution definition cannot prescind from a multi-event analysis of the full data set. It is found that the resolution of the event-by-event fold-to-multiplicity conversion procedure depends on the characteristics of the detection system, but not exclusively. The dependence on the particular multiplicity distribution investigated is discussed. It is concluded that event-by-event high-resolution impact parameter measurements can only be performed with very efficient and granular detection systems, but a gross event classification into central and peripheral collisions can be performed even with detection efficiency as low asΩ=0.3.

TFA catalyzes the alkylation of oxazolones, oxindoles, benzofuranones, and pyrazolones by carbocations generated in situ from alcohols (II) or (XIII), to give the corresponding derivatives bearing a quaternary carbon center.

Bifunctional amino-thiourea-catalyzed reaction of anthrones (I) and (IV) with β-nitrostyrene derivatives (II) exclusively affords the Michael adducts (III) and (V), respectively.

The title compounds are obtained through a Michael—Michael-aldol reaction in good yields and with high diastereo- and enantioselectivity.

The title reaction affords spirooxindole derivatives in good yields and with high diastereo- and enantioselectivity.

Isospin dependence of dynamical and thermodynamical properties observed in reactions 40Ca+ 40,48Ca and 40Ca + 46Ti at 25 MeV/nucleon has been studied. We used the CHIMERA multi-detector array. Strong isospin effects are seen in the isotopic distributions of light nuclei and in the competition between different reaction mechanisms in semi-central collisions. We will show also preliminary results obtained in nuclear collision 48Ca + 48Ca at 25MeV/nucleon, having very high N/Z value in the entrance channel (N/Z = 1. 4). The enhancement of evaporation residue production confirms the strong role played by the N/Z degree of freedom in nuclear dynamics.

Lanthanum bromide scintillation detectors produce very high light outputs (∼60,000 ph/MeV) within a very short decay time (typically ∼20 ns) which means that high instantaneous currents can be generated in the photocathode and dynode chain of the photomultiplier tube (PMT) used for the scintillation readout. The net result is that signal saturation can occur long before the recommended PMT biasing conditions can be reached. In search of an optimized light readout system for LaBr3, we have tested and compared two different PMT configurations for detection of gamma-rays up to 15 MeV. This range was chosen as being appropriate for gamma-ray remote sensing and medium energy nuclear physics applications. The experiments were conducted at two facilities: the Laboratori Nazionali del Sud (LNS) in Catania, Italy [1] and the High Intensity Gamma-ray Source (HIγS) at Triangle University Nuclear Laboratory, in Durham, North Carolina, USA [2] . The PMT configurations we have tested are (1) a standard dynode chain operated under-biased; (2) a 4-stage reduced chain operated at nominal inter-dynode bias. The results are that shortening the number of active stages, as in configuration (2), has advantages in preserving energy resolution and avoiding PMT saturation over a large energy range. However, the use of an under-biased PMT, configuration (1), can still be considered a satisfactory solution, at least in the case of PMTs manufactured by Photonis. The results of this study will be used in support of the Mercury Gamma-ray and Neutron Spectrometer (MGNS) on board of BepiColombo, the joint ESA/JAXA mission to Mercury, scheduled for launch in 2014.

The fragmentation of quasi-projectiles from the nuclear reaction $^{40}$Ca+$^{12}$C at 25 MeV/nucleon was used to produce excited states candidates to $\alpha$-particle condensation. Complete kinematic characterization of individual decay events, made possible by a high-granularity 4$\pi$ charged particle multi-detector, reveals that 7.5$\pm$4.0% of the particle decays of the Hoyle state correspond to direct decays in three equal-energy $\alpha$-particles., Comment: Phys. Lett. B, in press

Neutral pion production has been studied in the $^{36}\mathrm{Ar}$${+}^{27}$Al reaction at 95 MeV/nucleon with the aim to get a quantitative estimate of its impact-parameter dependence. A near 4\ensuremath{\pi} multidetector has been used to detect both the gamma rays originating from the ${\mathrm{\ensuremath{\pi}}}^{0}$ decay and the associated charged particles. The charged particle multiplicity has been used in the present analysis as a global variable to extract the impact parameter scale. A comparison with a Boltzmann-Nordheim-Vlasov calculation, whcih takes into account the effect of pion reabsorption in the nuclear medium, has been performed.

The dependence of the response to γ-rays of a large volume Ge detector on the interval width of a selected initial rise pulse slope is investigated. The number of escape events associated with a small pulse slope is found to be greater than the corresponding number of full energy events. An escape event rejection procedure based on the observed correlation between energy deposition and pulse shape is discussed. Such a procedure seems particularly suited for the design of highly granular large volume Ge detector arrays.

Non-statistical gamma rays of energy ranging in the interval from 5 MeV to 12 MeV are found to be emitted in coincidence with projectile-like fragments from the quasi-elastic 28 Si + 64 Ni reaction measured at E lab = 143 MeV. Boltzmann-Nordheim- Vlasov calculations are consistent with the hypothesis that they are originated from surface oscillations, of quadrupole or higher multipolarity, of the two colliding nuclei.

The response function of MEDEA BaF2 crystals to high energy photons, up to 280 MeV, has been studied using monochromatic γ-rays from the in flight annihilation of positron beams. The experimental response functions are compared to the results of Monte Carlo simulations based on the EGS3 code and parametrized over the whole investigated energy range.

Complex fragments have been detected in singles and in γ-particle coincidence measurements for the 19 F + 64 Ni system, at 118 MeV incident energy. Cross sections for the excited states of the complex fragments were measured detecting the characteristic γ-transitions deexciting these states. The measurement of cross sections for the population of the ground and excited states of 18 O and 13 C, as well as of the production cross sections of heavy residues in coincidence with these ejectiles, as a function of the total dissipated energy, indicate an evolution of energy sharing, with increasing mass transfer, from equipartition to thermal equilibrium.

High energy photon spectra have been measured in several 58Ni induced reactions at 30A MeV incident energy. A two source analysis of the data has been performed using a two exponential parameterization of the associated gamma spectra. The relative intensity of the two components has been deduced as a function of the total mass of the interacting system and of the impact parameter. To attempt a characterization of the emission sources, correlations between photons and IMF's have been measured for the first time.

A new, practical and enantioselective entry to direct precursors of quaternary α-alkyl-α-amino acids is developed.

The first highly diastereo- and enantioselective organocatalytic synthesis of 2,2-disubstituted-2H-oxazol-5-ones is described. The addition of oxazolones to maleimides is promoted by bifunctional thiourea catalysts, which afford the corresponding 2,2-disubstituted-2H-oxazol-5-ones with total regio- and stereocontrol.

In spite of the tremendous growth experienced by the field of asymmetric organocatalysis in the last decade, it is important to realize that we are still far away from having explored all of the possible pathways in organocatalysis ‘territory'; the application of the organocatalysis concept can still provide new catalysts and reactions for a variety of asymmetric organic transformations. To exemplify this assertion, we summarize the research performed in our laboratory over the past two years which has led to the development of new enantioselective approaches to organometallic compounds, to the desymmetrization of prochiral ketones, to functionalized cyclopropanes and piperidines, to fluorinated compounds, and to quaternary ?-amino acids, among others.

The development of new asymmetric methodologies that afford different structures in an enantioselective fashion is one of the most exciting goals for chemists nowadays. In this subject, lately, the use of sulfones has become a fast growing field. From the works of Tan and Shibata until the last works of Palomo, sulfones have demonstrated their versatility and power in organocatalytic asymmetric reactions. Moreover, the easy removal of sulfones with Mg or Hg/Na makes this group a perfect choice to afford easily naked alkyls. Remarkably, bissulfones can be used as nucleophiles or electrophiles, being vinyl sulfones excellent electrophiles, while bismethylensulfones derivatives such as fluoro are excellent nucleophiles. This double possibility has been studied by several research groups, leading to new methodologies that allow obtaining formally simple alkylation in an enantioselective fashion, by using organocatalysis. The aim of this tutorial review is to summarize the last trends in the use of sulfones in organocatalytic processes, giving a complete scenario of these new reagents.

Oxazolones or azlactones are among the most-common starting materials for the synthesis of quaternary amino acids. Since the seminal works of Steglich and co-workers until the recent examples from Ooi and co-workers, azlactones have been the focus of intense research. Oxazolones are also widely used in organometallic chemistry; however, with the "renaissance" of organocatalysis, this reagent has emerged as an important starting material for a broad range of new organocatalytic asymmetric methodologies. In this Focus Review, we aim to cover all of these new organocatalytic methodologies. We begin by discussing the dynamic kinetic resolution reactions developed with azlactones. Then, we disclose the organocatalytic rearrangements. Finally, we focus on the use of oxazolones as nucleophiles in organocatalytic processes.

A new, easy, and highly enantioselective method for the synthesis of quaternary α-alkyl-α-amino acids based on organocatalysis is described.

The synthesis of spiro compounds via a Michael-Michael-aldol reaction is reported. The reaction affords spirooxindole derivatives in good yields and in almost diastereo- and enantiopure form. Moreover, the reaction works with several heterocycles such as oxindoles, benzofuranones, pyrazolones or azlactones rendering the final spiro compounds in good yields and excellent stereoselectivities.

For the first time, the addition of anthrones to maleimides catalyzed by bifunctional thiourea catalysts is reported. The thiourea moiety is able to activate the maleimide and the tertiary amine deprotonates the anthrone, furnishing the final Diels–Alder or Michael adducts in excellent yields and enantioselectivities.

Since the serendipitous discovery of ferrocene by Pauson and Kealy in 1951, it has become one of the most important structures in Organic Chemistry. Lately, kinetic resolution has emerged as a useful tool for the synthesis of planar chiral ferrocenes. This review aims to cover and discuss the development of this topic.

A suite of computer codes, developed at the University of Minnesota, for the analysis of reacting hypersonic boundary layer stability has been used successfully by many different researchers in a wide range of applications. However, these applications have been limited by the software to the analysis of axisymmetric or two-dimensional flows or to analysis in the symmetry planes of three-dimensional flows. This paper introduces the latest version of the software suite which has been extended for the analysis of three-dimensional flows. Comparisons are made with the already well-tested two-dimensional version of the codes, and results are presented to illustrate the new capabilities for analysis of three-dimensional flows.

Flight 1. A 7 degree sphere-cone fore body was employed to determine likely transition characteristics and location at different times in the flight path. The implications of a shroud encapsulating the vehicle on placement of the pitot tube were also investigated. Since ground-tests are a major component of the HIFiRE campaign, the effectiveness of large-eddy simulations (LES) in predicting isolator dynamics was evaluated by comparison with experimental data. Finally, high-fidelity, three-dimensional simulations were employed to examine inlet-combustor coupling effects in a scramjet flow path. This is particularly relevant for configurations where the isolator segment is relatively short. Reynolds-averaged Navier-Stokes (RANS) with a k-w turbulence model, as well as LES, were performed with a finite-rate hydrocarbon-air mixture on the integrated inlet and combustor flow path, and compared to sequentially performed situations. The upstream influence of the combustor is considerably larger when the solution is obtained in an integrated fashion and sequential simulations may be overly optimistic in predicting un-start. Parametric studies indicate that reducing the fuel injection and equivalence ratio increases mixing efficiency in certain ranges, while reducing the tendency towards un-start.

The development of new asymmetric methodologies that afford different structures in an enantioselective fashion is one of the most exciting goals for chemists nowadays. In this subject, lately, the use of sulfones has become a fast growing field. From the works of Tan and Shibata until the last works of Palomo, sulfones have demonstrated their versatility and power in organocatalytic asymmetric reactions. Moreover, the easy removal of sulfones with Mg or Hg/Na makes this group a perfect choice to afford easily naked alkyls. Remarkably, bissulfones can be used as nucleophiles or electrophiles, being vinyl sulfones excellent electrophiles, while bismethylensulfones derivatives such as fluoro are excellent nucleophiles. This double possibility has been studied by several research groups, leading to new methodologies that allow obtaining formally simple alkylation in an enantioselective fashion, by using organocatalysis. The aim of this tutorial review is to summarize the last trends in the use of sulfones in organocatalytic processes, giving a complete scenario of these new reagents.

A new, easy, and highly enantioselective method for the synthesis of quaternary alpha-alkyl-alpha-amino acids based on organocatalysis is reported. The addition of oxazolones to 1,1-bis(phenylsulfonyl)ethylene is efficiently catalyzed by simple chiral bases or thioureas. The reaction affords alpha,alpha-disubstituted alpha-amino acid derivatives with complete C4 regioselectivity and with excellent yields and enantioselectivities. This methodology is complementary to previously reported enantioselective approaches to quaternary alpha-amino acids and allows the synthesis of alpha-phenyl-alpha-alkyl-alpha-amino acids and alpha-tert-butyl-alpha-alkyl-alpha-amino acids. It has distinct advantages in terms of operational simplicity, enviromentally friendly conditions, and suitability for large-scale reactions.