Characterization of the energy distribution of neutrons generated by 5 MeV protons on a thick beryllium target at different emission angles.

Neutron energy spectra at different emission angles, between 0° and 120° from the Be(p,xn) reaction generated by a beryllium thick-target bombarded with 5 MeV protons, have been measured at the Legnaro Laboratories (LNL) of the Italian National Institute for Nuclear Physics research (INFN). A new and quite compact recoil-proton spectrometer, based on a monolithic silicon telescope, coupled to a polyethylene converter, was efficiently used with respect to the traditional Time-of-Flight (TOF) technique. The measured distributions of recoil-protons were processed through an iterative unfolding algorithm in order to determine the neutron energy spectra at all the angles accounted for. The neutron energy spectrum measured at 0° resulted to be in good agreement with the only one so far available at the requested energy and measured years ago with TOF technique. Moreover, the results obtained at different emission angles resulted to be consistent with detailed past measurements performed at 4 MeV protons at the same angles by TOF techniques

Microdosimetry on nanometric scale with a new low-pressure avalanche-confinement TEPC

The tissue equivalent proportional counter (TEPC) is the most accurate device for measuring the microdosimetric properties of a particle beam, nevertheless no detailed information on the track structure of the impinging particles can be obtained, since the lower operation limit of common TEPCs is about 0.3 μm. On the other hand, the pattern of particle interactions is measured by track-nanodosimetry, which derives the single-event distribution of ionization cluster size at the nanometric scale. Anyway, only three nanodosimeters are available worldwide. A feasibility study for extending the performances of TEPC down to the nanometric region was performed and a novel avalanche-confinement TEPC was designed and constructed. This detector is constituted by a cylindrical chamber, based on a three-electrode structure, connected to a vacuum and gas flow system to ensure a continuous replacement of the tissue equivalent gas, thus allowing to simulate different biological site sizes in the range 300-25 nm. This TEPC can be calibrated by exploiting a built-in alpha source and a miniaturized solid-state detector as a trigger. Irradiations with photons, fast neutrons and two hadron beams demonstrated the good performances of the device. A satisfactory agreement with FLUKA simulations was obtained

Invasion status of the common carp Cyprinus carpio in inland waters of Argentina

This study documents the presence of Cyprinus carpio in 119 natural environments and 49 artificial habitats in Argentina, showing an exponential increment of invaded locations over time since it was introduced in the nineteenth century. Geographic expansion patterns revealed that since its initial introduction, species records demonstrate an increment in the central portion of the country only after 1970 and subsequent expansion after 1990 to the north, west and south. Using an environmental similarity index it was determined that more than half the country offers good conditions for C. carpio establishment. Environmental factors and anthropogenic impacts are relevant drivers that can account for the current and future distribution of C. carpio in Argentina.Instituto de Limnología "Dr. Raúl A. Ringuelet

Effect of photoperiod on ovarian maturation in <i>Cheirodon interruptus</i> (Teleostei: Characidae)

Cheirodon interruptus is a ubiquitous small characid that inhabits the Pampean region and commonly used as bait. Its vast market is supplied from the wild population causing a significant environmental impact. In this study, we assess the effect of photoperiod on ovarian maturation in order to evaluate its potential as a tool to manipulate reproduction under artificial conditions. Four treatments in triplicate (light: dark, L: D) were tested: 24L: 0D, 12L: 12D, 0L: 24D and a progressive photoperiod corresponding to the daily photoperiod increments in wild during winter-spring transition, accelerated three times. The experiment was conducted for 45 days. Gonadosomatic index (GSI), oocyte mean diameter, vitellogenic oocyte proportions, plasma estradiol concentrations (E2), condition factor (Kn) and standard length were estimated. Values of mean GSI, oocyte diameter, vitellogenic oocyte proportions and E2 concentration were maximum in the progressive treatment indicating vitellogenesis stimulation. In turn the same parameters were minimum in the 24L: 0D, revealing the vitellogenesis inhibition. This study showed that photoperiodic regime play an important role in the onset of ovarian maturation in C. interruptus.Instituto de Limnología "Dr. Raúl A. Ringuelet"Facultad de Ciencias Veterinaria

Nucleon-nucleon elastic scattering analysis to 2.5 GeV

A partial-wave analysis of NN elastic scattering data has been completed. This analysis covers an expanded energy range, from threshold to a laboratory kinetic energy of 2.5 GeV, in order to include recent elastic pp scattering data from the EDDA collaboration. The results of both single-energy and energy-dependent analyses are described.Comment: 23 pages of text. Postscript files for the figures are available from ftp://clsaid.phys.vt.edu/pub/said/n

Expansion of elevational range in a forest pest: Can parasitoids track their hosts?

We are thankful to Karim Senhadji and Ramon Ruiz-Puche for their help during the field work, and to Sara Garcia Morato for her contribution to quantifying rates of parasitism in PPM clutches at the laboratory. Two anonymous referees contributed to improve the manuscript. This study was supported by projects PROPINOL (PN22/2008), GESBOME (P06-RNM-1890) from Junta de Andalucia, REMEDINAL TE-CM (S2018/EMT-4338) from Comunidad de Madrid, ADAPTAMED (LIFE14 CCA/ES/000612) from LIFE program, and GILES (PCIN-2016-150) from the ERANET-LAC H2020 Programme.Gradients in elevation impose changes in environmental conditions, which in turn modulate species distribution and abundance as well as the interactions they maintain. Along the gradient, interacting species (e.g., predators, parasitoids) can respond to changes in different ways. This study aims to investigate how egg parasitism of a forest pest, the pine processionary moth (PPM), Thaumetopoea pityocampa, vary along an elevational gradient (190-2000 m.a.s.l.) in a mountain range of SE Spain, including areas of recent elevational expansion, for a seven years period (2008-2014). We used generalized linear mixed models to ascertain the effect of both elevation and the winter North Atlantic Oscillation (NAO) index (a proxy of interannual climatic conditions) on the rate of parasitism, and the occurrence probabilities of two parasitoid species: a PPM specialist and a generalist species. Since four pine species are stratified along the elevational gradient, we repeated all the analyses separately for lowlands (190-1300 m. a.s.l.) and uplands (1350-2000 m. a.s.l.). Results showed a decrease in both parasitism rate and probability of occurrence of the two main parasitoid species with elevation, although decline was more severe for the specialist species. The effect of elevation was more conspicuous and intense in uplands than in lowlands. Positive NAO winter values, associated with cold and dry winters, reduced the rate of parasitism and the probability of occurrence of the two main parasitoid species-but particularly for the generalist species-as elevation increases. In a context of climate warming, it is crucial to mitigate PPM elevational and latitudinal expansion. Increasing tree diversity at the PPM expansion areas may favor the establishment of parasitoids, which could contribute to synchronizing host- parasitoid interactions and minimize the risk of PPM outbreaks.Junta de Andalucia PN22/2008REMEDINAL TE-CM from Comunidad de Madrid S2018/EMT-4338ADAPTAMED from LIFE program LIFE14 CCA/ES/000612GILES from the ERANET-LAC H2020 Programme PCIN-2016-150Junta de Andalucia P06-RNM-189

Project of an advanced ISOL facility for exotic beams at LNL

Abstract 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

Evidence of a landlocked reproducing population of the marine pejerrey Odontesthes argentinensis (Actinopterygii; Atherinopsidae)

In South America, the order Atheriniformes includes the monophyletic genus Odontesthes with 20 species that inhabit freshwater, estuarine and coastal environments. Pejerrey Odontesthes argentinensis is widely distributed in coastal and estuarine areas of the Atlantic Ocean and is known to foray into estuaries of river systems, particularly in conditions of elevated salinity. However, to our knowledge, a landlocked self‐sustaining population has never been recorded. In this study, we examined the pejerrey population of Salada de Pedro Luro Lake (south‐east of Buenos Aires Province, Argentina) to clarify its taxonomic identity. An integrative taxonomic analysis based on traditional meristic, landmark‐based morphometrics and genetic techniques suggests that the Salada de Pedro Luro pejerrey population represents a novel case of physiological and morphological adaptation of a marine pejerrey species to a landlocked environment and emphasises the environmental plasticity of this group of fishesFil: Colautti, Dario César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Miranda, Leandro Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: González Castro, M.. Universidad Nacional de Mar del Plata; ArgentinaFil: Villanova, Vanina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Strüssmann, Carlos A.. Tokyo University Of Marine Science And Technology; JapónFil: Mancini, Miguel Alberto. Universidad Nacional de Río Cuarto; ArgentinaFil: Maiztegui, Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Berasain, Gustavo. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; ArgentinaFil: Hattori, Ricardo Shohei. Tokyo University of Marine Science and Technology; JapónFil: Grosman, Manuel Fabián. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Sanzano, Pablo Miguel. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Lozano, I.. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Llamazares Vegh, Sabina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Salinas, V.. Universidad Nacional de Río Cuarto; ArgentinaFil: Del Ponti, O.. Universidad Nacional de La Pampa; ArgentinaFil: Fresno, P.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: Minotti, Priscilla Gail. Universidad Nacional de San Martín; ArgentinaFil: Yamamoto, Y.. Tokyo University Of Marine Science And Technology; JapónFil: Baigún, C.. Universidad Nacional de San Martín; Argentin