Will the Italian endemic gudgeon, Gobio benacensis, survive the interaction with the invasive introduced Gobio gobio?

The genus Gobio in Italy was represented by the endemic species G. benacensis. The original distribution of this species was the Padano-Venetian district, but since a long time it was introduced in central Italy. Introductions of alien species to Italy during the last 10 years brought the sudden introduction of the Danubian G. gobio. Genetic and morphological analyses revealed the extensive presence of G. gobio, which rapidly colonised several rivers in Italy causing the progressive decline of G. benacensis, which now should be considered as an endangered species. Among examined populations those found in the Tagliamento River and transplanted in the Ombrone River represent genetic reservoirs of this species which will probably disappear in northern Italy

Occurrence of the scalloped ribbonfish Zu cristatus(Lampridiformes) in coastal waters of the central Tyrrhenian Sea, Italy

The occurrence of two individuals of Zu cristatus at 2 m depth in coastal waters of the Gulf of Castellamare (Tyrrhenian Sea, Italy) together with records of this rare pan-Oceanic mesopelagic species is reported. Analyses of two mitochondrial genes (12 s and 16 s; 936 bp) revealed a 2.6% sequence divergence between Mediterranean and Pacific (Japanese) samples of the species

Karyotype and genome size of Iberochondrostoma almacai (Teleostei, Cyprinidae) and comparison with the sister-species I.lusitanicum

This study aimed to define the karyotype of the recently described Iberian endemic Iberochondrostoma almacai, to revisit the previously documented chromosome polymorphisms of its sister species I.lusitanicum using C-, Ag-/CMA3 and RE-banding, and to compare the two species genome sizes. A 2n = 50 karyotype (with the exception of a triploid I.lusitanicum specimen) and a corresponding haploid chromosome formula of 7M:15SM:3A (FN = 94) were found. Multiple NORs were observed in both species (in two submetacentric chromosome pairs, one of them clearly homologous) and a higher intra and interpopulational variability was evidenced in I.lusitanicum. Flow cytometry measurements of nuclear DNA content showed some significant differences in genome size both between and within species: the genome of I. almacai was smaller than that of I.lusitanicum (mean values 2.61 and 2.93 pg, respectively), which presented a clear interpopulational variability (mean values ranging from 2.72 to 3.00 pg). These data allowed the distinction of both taxa and confirmed the existence of two well differentiated groups within I. lusitanicum: one that includes the populations from the right bank of the Tejo and Samarra drainages, and another that reunites the southern populations. The peculiar differences between the two species, presently listed as “Critically Endangered”, reinforced the importance of this study for future conservation plans

The Evolution of Compact Binary Star Systems

We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs) within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA). Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure

Roles of P2 receptors in glial cells: focus on astrocytes

Central nervous system glial cells release and respond to nucleotides under both physiological and pathological conditions, suggesting that these molecules play key roles in both normal brain function and in repair after damage. In particular, ATP released from astrocytes activates P2 receptors on astrocytes and other brain cells, allowing a form of homotypic and heterotypic signalling, which also involves microglia, neurons and oligodendrocytes. Multiple P2X and P2Y receptors are expressed by both astrocytes and microglia; however, these receptors are differentially recruited by nucleotides, depending upon specific pathophysiological conditions, and also mediate the long-term trophic changes of these cells during inflammatory gliosis. In astrocytes, P2-receptor-induced gliosis occurs via activation of the extracellular-regulated kinases (ERK) and protein kinase B/Akt pathways and involves induction of inflammatory and anti-inflammatory genes, cyclins, adhesion and antiapoptotic molecules. While astrocytic P2Y1 and P2Y2,4 are primarily involved in short-term calcium-dependent signalling, multiple P2 receptor subtypes seem to cooperate to astrocytic long-term changes. Conversely, in microglia, exposure to inflammatory and immunological stimuli results in differential functional changes of distinct P2 receptors, suggesting highly specific roles in acquisition of the activated phenotype. We believe that nucleotide-induced activation of astrocytes and microglia may originally start as a defence mechanism to protect neurons from cytotoxic and ischaemic insults; dysregulation of this process in chronic inflammatory diseases eventually results in neuronal cell damage and loss. On this basis, full elucidation of the specific roles of P2 receptors in these cells may help exploit the beneficial neuroprotective features of activated glia while attenuating their harmful properties and thus provide the basis for novel neuroprotective strategies that specifically target the purinergic system

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy

A search for new physics is performed in events with two same-sign isolated leptons, hadronic jets, and missing transverse energy in the final state. The analysis is based on a data sample corresponding to an integrated luminosity of 4.98 inverse femtobarns produced in pp collisions at a center-of-mass energy of 7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of 140 increase in integrated luminosity over previously published results. The observed yields agree with the standard model predictions and thus no evidence for new physics is found. The observations are used to set upper limits on possible new physics contributions and to constrain supersymmetric models. To facilitate the interpretation of the data in a broader range of new physics scenarios, information on the event selection, detector response, and efficiencies is provided.Comment: Published in Physical Review Letter

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Compressed representation of a partially defined integer function over multiple arguments

In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one

Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV

The azimuthal anisotropy of charged particles in PbPb collisions at nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pt) range up to approximately 60 GeV. The data cover both the low-pt region associated with hydrodynamic flow phenomena and the high-pt region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with pt, reaching a maximum around pt = 3 GeV, and then to gradually decrease to almost zero, with the decline persisting up to at least pt = 40 GeV over the full centrality range measured.Comment: Replaced with published version. Added journal reference and DO