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We developed a Monte-Carlo code for describing the reaction kinematics of the two-body direct processes employed of the EXOTIC beam-line of the Laboratori Nazionali di Legnaro (LNL) for the production of light weakly bound radioactive ion beams at energies of a few MeV/u. The program calculates the phase-space distribution of both primary and secondary beams at the target exit and uses these quantities to optimize the secondary beam selection with the EXOTIC spectrometer. The calculations have been performed and compared with the available experimental data for two reactions: (1)H(2)((17)O, (17)F)n and (3)He((6)Li, (8)B)n. (c) 2008 Elsevier B.V. All rights reserved.

Partial-fusion cross-sections for the systems 6Li + 208Pb, 9Be + 209Bi have been determined. The effect of breakup on fusion for weakly bound projectiles 6Li and 9Be incident on 208Pb or 209Bi targets has been discussed comparing experimental fusion cross-section excitation functions to those evaluated with a semi-classical approach. It is shown that complete fusion of a weakly bound projectile with heavy target is reduced, whereas the breakup process has very little influence on the total-fusion cross-section for some of the studied systems at energies above the Coulomb barrier.

In the framework of the European program to define a second generation Radioactive Ion Beam facility, LNL are proposing the construction in the next five–seven years of a specialized national facility for RIB originated by fission fragments produced by secondary neutrons. It consists on a two-accelerator ISOL-type facility to provide intense neutron-rich radioactive ion beams of highest quality, in the range of masses between 80 and 160. The conceptual design is based on a high intensity 50 MeV (100 kW) proton linac as driver and on the availability of the heavy-ion accelerator ALPI as post accelerator. The estimated neutron yield is 2×1014 n/s at 0°, high enough to satisfy the demand for an advanced RIB facility. An intense R&D program on different items is actually in progress in collaboration with other Laboratories and University groups and is moving in a European context.

Determining the biological effects of cosmic rays and other natural ionizing radiations, could possibly help us in shedding light on the more general problem of low-dose ionizing-radiation effects. In this work we provide a survey of the most recent studies available on epidemiological methods: we discuss the main difficulties in using these methods, as well as the discrepancies in their results.

Introduction Nous rapportons une contamination inter-echantillons sur automate Ortho © AutoVue Innova dont le dossier de verification de methode incluait un test d’absence de contamination selon le principe suivant : apres rincage (verifie par 1 negatif), 1 echantillon fortement positif (IgG de titre 1/64) 3 fois consecutivement, puis 3 negatif consecutivement, puis un positif, places de facon que l’aiguille preleve d’abord un positif puis un negatif. Description La contamination a touche 6 echantillons, analyses juste apres le serum contaminant : 5 depistages et 1 controle qualite interne (CQI) non conforme qui a donne l’alerte. Apres rincage-decontamination, les depistages ont tous ete retrouves negatifs et le CQI conforme. L’etude d’impact de cette non-conformite a mis en evidence 2 prelevements anterieurs du patient traites sur l’automate dans les jours precedents (j−1 et j−3). Lors des 2 passages, les 2 echantillons analyses juste apres le plasma suspect ont ete contamines. Pour l’un des passages il s’agissait du depistage et de l’identification conjointe d’un patient, (connu avec un allo-anti-D), ce qui a entraine le rendu d’un resultat errone : anti-Fya rendu par exces. Pour l’autre, le depistage positif n’a ensuite pas ete confirme en identification. Resultat Le serum contaminant presentait un anti-Fya titrant au 1/65 536 en technique tube saline, explique par une transfusion de ce patient immunise, en urgence vitale immediate, en CGR phenotypes Rh-K de phenotype Fya non teste a j−18. Conclusion Le titrage tres eleve nous permet d’identifier la cause de cette contamination inter-echantillon due a une limite de methode et non pas une defaillance de l’automate.

The analysis of the Rome NM-64 data, performed on the occasion of 8 solar flares accompanied by gamma-bursts and 10 solar flares accompanied by large X-ray fluxes, shows that the solar energetic neutron events could be detected by ground-based stations particularly when they are located at mountain altitude and middle-low latitudes. Suggestions for improving the neutron monitor efficiency for detecting solar neutron events are given.

A comparison between the quiet-time magnetic-field measurements performed on the GEOS 1 spacecraft in the period May 13, 1977–December 13, 1977 and the predictions of four geomagnetic-field models is presented. For the explored magnetospheric region the best approximation to the GEOS 1 measurements is given by the 1976 Olson and Pfitzer model: the difference between its predictions and the experimental data never exceeds 3 per cent in the absolute value of the field and 3 degrees in the field direction.

All the flare-not-associated Forbush decreases (NAFDs) are investigated over the period 1975–1979. The connection between the NAFDs occurrence and the central meridian passage of strong active regions producing great flare-associated FDs confirms the flare origin of the NAFDs. The interplanetary perturbations at the eastern and western boundaries of the modulated region are found to be long-living corotating structures. These structures seem to mark also the boundaries of the region in which the (1⤜4) MeV protons accelerated by interplanetary flare-generated shocks are confined.

In-beam γ-ray spectroscopy was performed in the reactions24Mg(32S, 3pn)52Mn and51V(3He, 2n)52Mn. The measurements of γ-rays excitation functions, angular distributions and γ-γ coincidences allowed us to identify the following new levels: 2285.8 keV, 8+; 2907.3 keV, 9+; 3836.0 keV,(11)+. The comparison with shell model calculations suggests that essentially high-spin states of the (1f7/2) n -configuration are observed.

Interplanetary plasma data taken near 1 AU by a variety of spacecraft (Imp 1, Vela 2-4, Explorer 33-35, and Heos 1) from 1963 to 1971 are used to study the long-term variations of the solar wind proton properties. An intercalibration among the different experiments is performed in order to obtain a coherent set of data. The most interesting result is a 40% reduction of the proton density between the minimum and the maximum of the solar activity cycle. The observed density variation occurs throughout the velocity range; however, a limited sample of data could suggest that at very low velocities (below 300 km/sec) the density is independent of the solar activity. The proton bulk velocity is remarkably constant during the period considered; small increases of the average speed occurring in 1968 and 1971 cannot be attributed to the solar cycle. No clear trend is exhibited by the proton temperature; differences among the various experiments probably have an instrumental origin.

Interplanetary plasma and magnetic-field parameters, measured by the ESRO satellite HEOS-1, have been correlated with theD st , taken as an index of the overall geomagnetic activity. It is found that two different states exist for the interaction between the solar wind and the magnetosphere: they correspond to quiet periods (D st positive) and to disturbed conditions (main phase of geomagnetic storms,i.e. D st negative). In disturbed conditions the magnetosphere appears to be much more sensitive to variations of the solar-wind dynamical pressure than in periods of positiveD st .

The direction of the solar wind has been measured by analyzing the data obtained with the MIT Faraday cup on the IMP 1 satellite. During the period November 27, 1963, to February 24, 1964, the solar wind was, on the average, in the ecliptic plane (50% of cases between −2° and +2°) and came from west of the sun on 72% of the cases; the average value of the ecliptic longitude was −1.5°. If a systematic error of 1° is allowed, the above figures become 56% and 86% in the two extreme cases. This result indicates that, in the above period of time, the solar wind has tendency to anticorotate with the sun.

A description is given of the analysis of the solar wind angular data from the satellite HEOS 1 and a comparison is made with the data obtained by Explorer 33, in the period of time from January 1967 to April 1970. The observed flow direction shows a temporal behaviour which sug gests the possbility of a long period regular variation.

The mean lives of three low-lying levels of53Mn at excitation energies of 1.29 MeV (3/2−1), 1.44 MeV (11/2−) and 1.62 MeV (9/2−) have been measured using the Doppler-shift attenuation method with p-γ coincidences in the50Cr(α, pγ)53Mn reaction. The following values have been obtained for the three levels, respectively:τ m =(0.87±0.22), (1.15 ± 0.38) and (0.56 ± 0.15) ps. Branching and multipole mixing ratios in agreement with other recent experimental data have also been obtained. Combining these results we find thatM1 transitions between states assumed to belong to the basic (πf 7/3)−3 multiplet are retarded by factors ranging between 50 to 100, whileE2 transitions are enhanced by factors of the order of 10. This is in agreement with the behaviour of51V (with (1f 7/2)3 configuration) supporting the basic shell-model features of nuclei with a48Ca core.

Human ciliopathies are hereditary conditions caused by defects of proteins expressed at the primary cilium. Among ciliopathies, Joubert syndrome and related disorders (JSRD), Meckel syndrome (MKS) and nephronophthisis (NPH) present clinical and genetic overlap, being allelic at several loci. One of the most interesting gene is TMEM67, encoding the transmembrane protein meckelin. We performed mutation analysis of TMEM67 in 341 probands, including 265 JSRD representative of all clinical subgroups and 76 MKS fetuses. We identified 33 distinct mutations, of which 20 were novel, in 8/10 (80%) JS with liver involvement (COACH phenotype) and 12/76 (16%) MKS fetuses. No mutations were found in other JSRD subtypes, confirming the strong association between TMEM67 mutations and liver involvement. Literature review of all published TMEM67 mutated cases was performed to delineate genotype-phenotype correlates. In particular, comparison of the types of mutations and their distribution along the gene in lethal versus non lethal phenotypes showed in MKS patients a significant enrichment of missense mutations falling in TMEM67 exons 8 to 15, especially when in combination with a truncating mutation. These exons encode for a region of unknown function in the extracellular domain of meckelin.