ASY-EOS experiment at GSI: Constraining symmetry energy with neutron and proton elliptic flows

The Equation Of State of asymmetric nuclear matter is of fundamental importance for both nuclear physics and astrophysics. However, the present understanding of the EOS is limited, largely due to the poor knowledge of the density dependence of the nuclear symmetry energy. In fact, while considerable progress has been made recently in determining the behaviour of symmetry energy at sub-normal nuclear matter density, much more work is still needed to probe its behaviour at high density. The ASY-EOS experiment at GSI will measure elliptic flow (squeeze-out) of neutrons, protons and light complex particles in reactions of isospin asymmetric systems at pre-relativistic energies, in order to provide quantitative information on the density dependence of symmetry energy at densities larger than the saturation one

Towards a model-independent constraint of the high-density dependence of the symmetry energy

Neutron-proton elliptic flow difference and ratio have been shown to be promising observables in the attempt to constrain the density dependence of the symmetry energy above the saturation point from heavy-ion collision data. Their dependence on model parameters like microscopic nucleon-nucleon cross-sections, compressibility of nuclear matter, optical potential, and symmetry energy parametrization is thoroughly studied. By using a parametrization of the symmetry energy derived from the momentum dependent Gogny force in conjunction with the T\"{u}bingen QMD model and comparing with the experimental FOPI/LAND data for 197Au+197Au collisions at 400 MeV/nucleon, a moderately stiff, x=-1.35 +/- 1.25, symmetry energy is extracted, a result that agrees with that of a similar study that employed the UrQMD transport model and a momentum independent power-law parametrization of the symmetry energy. This contrasts with diverging results extracted from the FOPI $\pi^{-}/\pi^{+}$ ratio available in the literature.Comment: 18 pages, 3 figures, accepted for publication in Phys. Rev.

Production cross sections for intermediate mass fragments from dynamical and statistical decay of projectile-like fragments in Sn 124 + Ni 64 and Sn 112 + Ni 58 collisions at 35 A MeV

Background: In heavy-ion collisions at intermediate energies the production of light charged particles and intermediate mass fragments (IMFs) is due to different reaction mechanisms and different time scales, ranging from fast dynamical processes to statistical emission from the equilibrated system. Purpose: We compare the IMF statistical and dynamical emission probabilities in collisions of a neutron-rich Sn124+Ni64 system and a neutron-poor Sn112+Ni58 system at the laboratory energy of 35 A MeV. Method: The IMFs production mechanism in semiperipheral reactions has been investigated in our previous works. In this paper, the analysis is expanded for the same set of data and production cross sections have been evaluated for dynamical and statistical emission in a coherent way for light and heavy fragments. Results: The data analysis has evidenced a strong competition between dynamical and statistical emission mechanisms. Probability of the dynamical emission of IMFs is strongly influenced by the (N/Z) ratio of the colliding system. Conclusions: It is demonstrated that the statistical emission is equally probable for the two systems, while the dynamical emission is enhanced for the neutron-rich system, especially for heavy fragments (Z≥6). The observed effect points at a high sensitivity of the prompt-dynamical emission to the (N/Z) ratio of a given system

Morphological variation of the newly confirmed population of the javelin sand boa, Eryx jaculus (Linnaeus, 1758) (Serpentes, erycidae) in Sicily, Italy

The presence of the Javelin sand boa in Sicily has recently been confirmed. Here the morphological characters and sexual dimorphism of the Sicilian population of Eryx jaculus are presented. Seven meristic and six metric characters in 96 specimens from Sicily were examined. The results show that tail length, snout-vent length, the distance between nostrils and the number of ventral and subcaudal scales are different between sexes. The characters found in the Sicilian population of the Javelin sand boa resemble those of the African population (ssp. jaculus) rather than the Eurasian population (ssp. turcicus), but biomolecular studies are necessary to understand its taxonomic identity

Flow probe of symmetry energy in relativistic heavy-ion reactions

Flow observables in heavy-ion reactions at incident energies up to about 1 GeV per nucleon have been shown to be very useful for investigating the reaction dynamics and for determining the parameters of reaction models based on transport theory. In particular, the elliptic flow in collisions of neutron-rich heavy-ion systems emerges as an observable sensitive to the strength of the symmetry energy at supra-saturation densities. The comparison of ratios or differences of neutron and proton flows or neutron and hydrogen flows with predictions of transport models favors an approximately linear density dependence, consistent with ab-initio nuclear-matter theories. Extensive parameter searches have shown that the model dependence is comparable to the uncertainties of existing experimental data. Comprehensive new flow data of high accuracy, partly also through providing stronger constraints on model parameters, can thus be expected to improve our knowledge of the equation of state of asymmetric nuclear matter.Comment: 20 pages, 24 figures, review to appear in EPJA special volume on nuclear symmetry energ

Neutrophil CD64 as a marker of infection in patients admitted to the emergency department with acute respiratory failure

Introduction: Cluster of differentiation 64 (CD64) is expressed on neutrophils during bacterial infections and sepsis. The aim of our study was to assess the CD64 expression in patients admitted to the emergency department (ED) with a triage diagnosis of acute respiratory failure (ARF) and/or dyspnea and to verify a relationship between its value and the presence of infection. Methods: We assessed neutrophil CD64 expression in peripheral blood of patients admitted to the ED with a diagnosis of ARF and/or dyspnea from September 2012 to April 2013. We mea- sured CD64 index by flow cytometry (Leuko64TM kit) and classified patients as infected within 12 hours from admission, without an infection within 12 hours but infected within 72 hours from admission, and not infected. The primary outcome was differentiating CD64 values of patients with a diagnosis of infection within 12 hours and 72 hours from admission, from those of patients without a diagnosis of infection. The secondary outcome was verifying a relationship between CD64 values and patients’ characteristics, Sequential Organ Failure Assessment score, and intensive care unit admission. Results: Of 212 patients included in the study, 40.1% were classified as infected within 12 hours from admission, 20.3% were without an infection 12 hours after admission but were infected within 72 hours, and 39.6% were not infected. The median CD64 index was higher in patients with an infection on admission (CD64 index: 3.58) than in those not considered infected (CD64 index: 1.37), P,0.0001. Among patients not infected at admission, the CD64 index was higher in those with an infection detected during the following hours of observation (CD64 index: 2.75) than in patients without a diagnosis of infection (CD64 index: 1.28), P,0.0001. A CD64 index .3.65 showed a sensitivity of 94.6%, a specificity of 86.8%, and an area under the receiver-operating characteristic curve of 0.952 for prediction of intensive care unit admission. Conclusion: CD64 index could represent a useful diagnostic tool for differential diagnosis of ARF in the ED

An innovative method for the detection of contaminant viral genome in cell cultures

The use of cell cultures involves different fields of biology, from diagnosis to research. Moreover, technologies based on animal cells represent a useful tool to the development of biological products for the prophylaxis and therapy in humans and animals. Therefore, it is necessary to perform quality controls, including virological tests. Several tests performed in research laboratories are able to discriminate one or more viral species, but it is not possible to demonstrate the presence of contaminant viral genome with one non-specific method. The aim of this work consisted on the realization of a biomolecular method able to detect and to identify by sequencing extraneous viral genome in cell cultures of animal and human origin in the absence of any specific information about the virus

What Healthcare Workers Should Know about Environmental Bacterial Contamination in the Intensive Care Unit

Intensive care unit- (ICU-) acquired infections are a major health problem worldwide. Inanimate surfaces and equipment contamination may play a role in cross-transmission of pathogens and subsequent patient colonization or infection. Bacteria contaminate inanimate surfaces and equipment of the patient zone and healthcare area, generating a reservoir of potential pathogens, including multidrug resistant species. Traditional terminal cleaning methods have limitations. Indeed patients who receive a bed from prior patient carrying bacteria are exposed to an increased risk (odds ratio 2.13, 95% confidence intervals 1.62\u20132.81) of being colonized and potentially infected by the same bacterial species of the previous patient. Biofilm formation, even on dry surfaces, may play a role in reducing the efficacy of terminal cleaning procedures since it enables bacteria to survive in the environment for a long period and provides increased resistance to commonly used disinfectants. No-touch methods (e.g., UV-light, hydrogen peroxide vapour) are under investigation and further studies with patient-centred outcomes are needed, before considering them the standard of terminal cleaning in ICUs. Healthcare workers should be aware of the role of environmental contamination in the ICU and consider it in the broader perspective of infection control measures and stewardship initiatives

Canine Mesenchymal Stem Cells from visceral and subcutaneuous adipose tissue for cell-based therapy

This study compared some characteristics of canine Adipose tissue-Derived Mesenchymal Stem Cells (cAD-MSCs) from subcutaneous and visceral fat. These findings were directed to obtain high quantity and quality cAD-MSCs for clinical cell-based therapy