Quark deconfinement and neutrino trapping in compact stars

We study the role played by neutrino trapping on the hadron star (HS) to quark star (QS) conversion mechanism proposed recently by Berezhiani and collaborators. We find that the nucleation of quark matter drops inside hadron matter, and therefore the conversion of a HS into a QS, is strongly inhibit by the presence of neutrinos.Comment: 3 pages, 3 figures. Talk given at the VIII International Conference on Strangeness in Quark Matter. Cape Town, South Africa, Septembre 200

Effect of Freezing and Thawing on Uptake of Amino Acids into Human Erythrocytes

ABSTRACT - The transport of C-amino acids into human erythrocytes and into erythrocytes which had been frozen and thawed was studied experimentally. The relative rates of uptake were found to be (in decreasing order): phenylalanine, leucine, alanine, trythophan, and glycine. Freezing (using gycerol as the cryoprotective additive) and thawing had no significant effect on either the magnitude of the rate constants or on the order of the above relative rates of amino acid uptake into erythrocytes suspended in isotonic TRIS-HCl buffer

CORNELIA DE LANGE SYNDROME AND RELATED DISORDERS: NEW INSIGHTS INTO GLOBAL TRANSCRIPTIONAL DISTURBANCES DUE TO MUTATIONS IN CHROMATIN-ASSOCIATED FACTORS

Cornelia de Lange syndrome (CdLS) is a rare disorder characterized by an extensive clinical heterogeneity. The main features of the syndrome are characteristic facial dysmorphisms and a variable level of intellectual disability, growth retardation and developmental delay. Though, the number and severity of the clinical signs vary among patients. An extensive genetic heterogeneity partially accounts for the reported clinical variability. Mutations in different cohesin-associated proteins are in fact responsible for the onset of the syndrome. The known CdLS-genes include NIPBL, SMC1A, SMC3, RAD21 and HDAC8. Alterations in the cohesin loader NIPBL are found in more than half of CdLS cases and are associated with a classical phenotype and with a high frequency of limb malformations. In addition, mosaicism has been proven to play an important role in association with NIPBL. Mutations in the structural elements SMC1A, SMC3 and RAD21 and in the regulator HDAC8 account for about 10-15% of CdLS cases. The phenotype of those patients who harbor mutations in these genes is usually milder or atypical. The five genes all together, also taking into account the role of mosaicism, can explain about 70% of CdLS cases. In an internationally assembled cohort of patients we were able to identify 109 mutations in NIPBL, 8 mutations in SMC1A, 15 mutations in SMC3 and 11 mutations in HDAC8, thus increasing the total number of mutations so far described for CdLS. In addition, by the use of next generation sequencing techniques we were able to identify mutations in five genes different from cohesin in six unrelated patients with a clinical diagnosis of CdLS. The five genes include those encoding for different subunits of the chromatin remodeling complex named SWI/SNF and for the transcriptional repressor ANKRD11. Mutations in these genes have been so far associated to Coffin-Siris syndrome and KBG syndrome, respectively. Protein-protein interaction experiments also showed a direct interaction of the SWI/SNF subunit SMARCB1 with the cohesin-related proteins NIPBL and SMC3. These direct link between cohesin and SWI/SNF subunits indicate that mutations affecting the two protein complexes might determine the deregulation of overlapping sets of genes. Our newly identified variants contribute to a better understanding of the correlation between genotype and phenotype in the presence of mutations in the known-CdLS genes. Notwithstanding, different pehotypes have been observed in patients carrying the same DNA alteration, hence suggesting that environmental factors may play an important role in the delineation of the observed clinical features. Additionally, the identification of mutations in chromatin-associated factors responsible for syndromes different from CdLS indicate the existence of a broad pleiotropy that should be taken into account while assessing the clinical and molecular diagnosis. Furthermore, we investigated the molecular mechanisms underlying the syndrome in the presence of missense substitutions or small in-frame deletions in SMC1A, a X-linked gene that localizes in a region of the X-chromosome that partially escapes X-inactivation in humans. Our expression analysis revealed that the transcript is expressed at higher levels in females as compared to males, and that there are no differences in the expression of the SMC1A protein between healthy and affected females. In addition, pyrosequencing analysis showed that CdLS female patients harboring mutations in SMC1A tend to express the wild type allele at higher levels as compared to the mutant allele. All together, these data suggests that the pathogenesis of the syndrome in the presence of mutations affecting SMC1A which do not disrupt the reading frame might be linked to a dominant negative effect exerted by the mutant protein on the wild type

The Role of Emotional Intelligence in Health Care Professionals Burnout

The purpose of this study is to explore the relationship between Emotional Intelligence (EI) and burnout in health care professionals. More specifically, this survey has the purpose of demonstrating the role of EI as a protective factor against the risk of burnout. Health professionals (doctors, nurses, and other caregivers) composed the sample. Data, collected during professional training, provided 148 employees. Major results of this survey underline the relationship between EI and burnout. As we expected, there is a negative and significant correlation between burnout and Emotional Intelligence. Moreover, burnout varies depending on length of service: burnout increases between 5 and 10 years of experience and decreases over 10 years. Indeed, burnout is differently expressed amongst healthcare professionals: more specifically, Psycho-physical exhaustion, Detriment of the relationships and Burnout (total score) has an impact on physician (doctors) more than other investigated health professionals. These findings seem to suggest the opportunity to improve Emotional Intelligence abilities through specific training programs, useful to promote the ability to cope with stress and to enrich the relationships in the workplace

Equation of state at high densities and modern compact star observations

Recently, observations of compact stars have provided new data of high accuracy which put strong constraints on the high-density behaviour of the equation of state of strongly interacting matter otherwise not accessible in terrestrial laboratories. The evidence for neutron stars with high mass (M =2.1 +/- 0.2 M_sun for PSR J0751+1807) and large radii (R > 12 km for RX J1856-3754) rules out soft equations of state and has provoked a debate whether the occurence of quark matter in compact stars can be excluded as well. In this contribution it is shown that modern quantum field theoretical approaches to quark matter including color superconductivity and a vector meanfield allow a microscopic description of hybrid stars which fulfill the new, strong constraints. The deconfinement transition in the resulting stiff hybrid equation of state is weakly first order so that signals of it have to be expected due to specific changes in transport properties governing the rotational and cooling evolution caused by the color superconductivity of quark matter. A similar conclusion holds for the investigation of quark deconfinement in future generations of nucleus-nucleus collision experiments at low temperatures and high baryon densities such as CBM @ FAIR.Comment: 6 pages, 2 figures, accepted for publication in J. Phys. G. (Special Issue

Random Graph-Homomorphisms and Logarithmic Degree

A graph homomorphism between two graphs is a map from the vertex set of one graph to the vertex set of the other graph, that maps edges to edges. In this note we study the range of a uniformly chosen homomorphism from a graph G to the infinite line Z. It is shown that if the maximal degree of G is `sub-logarithmic', then the range of such a homomorphism is super-constant. Furthermore, some examples are provided, suggesting that perhaps for graphs with super-logarithmic degree, the range of a typical homomorphism is bounded. In particular, a sharp transition is shown for a specific family of graphs C_{n,k} (which is the tensor product of the n-cycle and a complete graph, with self-loops, of size k). That is, given any function psi(n) tending to infinity, the range of a typical homomorphism of C_{n,k} is super-constant for k = 2 log(n) - psi(n), and is 3 for k = 2 log(n) + psi(n)

Neurotensin receptor 1 immunoreactivity in the peripheral ganglia and carotid body

In the present study we investigated, through immunohistochemistry, the presence and location of neurotensin receptor 1 (NTR1) in the peripheral ganglia and carotid body of 16 humans and 5 rats. In both humans and rats, NTR1 immunostained ganglion cells were found in superior cervical ganglia (57.4±11.6% and 72.4±11.4%, respectively, p<0.05), enteric ganglia (51.9±10.4% and 64.6±6.1%, p<0.05), sensory ganglia (69.2±10.7% and 73.0±13.1%, p>0.05) and parasympathetic ganglia (52.1±14.1% and 59.4±14.0%, p>0.05), supporting a modulatory role for NT in these ganglia. Positivity was also detected in 45.6±9.2% and 50.8±6.8% of human and rat type I glomic cells, respectively, whereas type II cells were negative. Our findings suggest that NT produced by type I cells acts in an autocrine or paracrine way on the same cell type, playing a modulatory role on chemoception