University of Cagliari

About: University of Cagliari is a education organization based out in Cagliari, Italy. It is known for research contribution in the topics: Population & Dopamine. The organization has 11029 authors who have published 29046 publications receiving 771023 citations. The organization is also known as: Università degli Studi di Cagliari & Universita degli Studi di Cagliari.

PSR J1756?2251: A New Relativistic Double Neutron Star System

Abstract: We report the discovery during the Parkes Multibeam Pulsar Survey of PSR J1756-2251, a 28.5 ms pulsar in a relativistic binary system. Subsequent timing observations showed the pulsar to have an orbital period of 7.67 hr and an eccentricity of 0.18. They also revealed a significant advance of periastron, 2585 ± 0002 yr-1. Assuming this is entirely due to general relativity implies a total system mass (pulsar plus companion) of 2.574 ± 0.003 M☉. This mass and the significant orbital eccentricity suggest that this is a double neutron star system. Measurement of the gravitational redshift, γ, and an evaluation of the Shapiro delay shape, s, indicate a low companion mass of less than 1.25 M☉. The expected coalescence time due to emission of gravitational waves is only ~1.7 Gyr, substantially less than a Hubble time. We note an apparent correlation between spin period and eccentricity for normally evolving double neutron star systems.

From models to pathogens: how much have we learned about Streptococcus pneumoniae cell division?

Abstract: Summary Streptococcus pneumoniae is an oval-shaped Gram-positive coccus that lives in intimate association with its human host, both as a commensal and pathogen. The seriousness of pneumococcal infections and the spread of multi-drug resistant strains call for new lines of intervention. Bacterial cell division is an attractive target to develop antimicrobial drugs. This review discusses the recent advances in understanding S. pneumoniae growth and division, in comparison with the best studied rod-shaped models, Escherichia coli and Bacillus subtilis. To maintain their shape, these bacteria propagate by peripheral and septal peptidoglycan synthesis, involving proteins that assemble into distinct complexes called the elongasome and the divisome, respectively. Many of these proteins are conserved in S. pneumoniae, supporting the notion that the ovococcal shape is also achieved by rounds of elongation and division. Importantly, S. pneumoniae and close relatives with similar morphology differ in several aspects from the model rods. Overall, the data support a model in which a single large machinery, containing both the peripheral and septal peptidoglycan synthesis complexes, assembles at midcell and governs growth and division. The mechanisms generating the ovococcal or coccal shape in lactic-acid bacteria have likely evolved by gene reduction from a rod-shaped ancestor of the same group.

Structural differences in two biochemically defined populations of cardiac mitochondria.

Abstract: To determine whether there are structural differences in two topologically separated, biochemically defined mitochondrial populations in rat heart myocytes, the interior of these organelles was exa...