Interaction of Gα₁₂ with Gα₁₃ and Gα_q signaling pathways

The G(12) subfamily of heterotrimeric G-proteins consists of two members, G(12) and G(13). Gene-targeting studies have revealed a role for G(13) in blood vessel development. Mice lacking the a subunit of G(13) die around embryonic day 10 as the result of an angiogenic defect. On the other hand, the physiological role of G(12) is still unclear. To address this issue, we generated Galpha(12)-deficient mice. In contrast to the Galpha(13)-deficient mice, Galpha(12)-deficient mice are viable, fertile, and do not show apparent abnormalities. However, Galpha(12) does not seem to be entirely redundant, because in the offspring generated from Galpha(12)+/-Galpha(13) intercrosses, at least one intact Galpha(12) allele is required for the survival of animals with only one Galpha(13) allele. In addition, Galpha(12) and Galpha(13) showed a difference in mediating cell migratory response to lysophosphatidic acid in embryonic fibroblast cells. Furthermore, mice lacking both Galpha(12) and Galpha(q) die in utero at about embryonic day 13. These data indicate that the Galpha(12)-mediated signaling pathway functionally interacts not only with the Galpha(13)- but also with the Galpha(q/11)-mediated signaling systems

Experimental method for measuring classical concurrence of generic beam shapes

Classical entanglement is a powerful tool which provides a neat numerical estimate for the study of classical correlations. Its experimental investigation, however, has been limited to special cases. Here, we demonstrate that the experimental quantification of the level of classical entanglement can be carried out in more general instances. Our approach enables the extension to arbitrarily shaped transverse modes and hence delivering a suitable quantification tool to describe concisely the modal structure

On the polytropic Bondi accretion in two-component galaxy models with a central massive BH

In many investigations involving accretion on a central point mass, ranging from observational studies to cosmological simulations, including semi-analytical modelling, the classical Bondi accretion theory is the standard tool widely adopted. Previous works generalized the theory to include the effects of the gravitational field of the galaxy hosting a central black hole and of electron scattering in the optically thin limit. Here, we apply this extended Bondi problem, in the general polytropic case, to a class of new two-component galaxy models recently presented. In these models, a Jaffe stellar density profile is embedded in a dark matter halo such that the total density distribution follows a r−3 profile at large radii; the stellar dynamical quantities can be expressed in a fully analytical way. The hydrodynamical properties of the flow are set by imposing that the gas temperature at infinity is proportional to the virial temperature of the stellar component. The isothermal and adiabatic (monoatomic) cases can be solved analytically; in the other cases, we explore the accretion solution numerically. As non-adiabatic accretion inevitably leads to an exchange of heat with the ambient, we also discuss some important thermodynamical properties of the polytropic Bondi accretion and provide the expressions needed to compute the amount of heat exchanged with the environment as a function of radius. The results can be useful for the subgrid treatment of accretion in numerical simulations, as well as for the interpretation of observational dat

Early suppression of lymphoproliferative response in dogs with natural infection by Leishmania infantum.

Dogs are the domestic reservoirs of zoonotic visceral leishmaniasis caused by Leishmania infantum. Early detection of canine infections evolving to clinically patent disease may be important to leishmaniasis control. In this study we firstly investigated the peripheral blood mononuclear cell (PBMC) response to leishmanial antigens and to polyclonal activators concanavalin A, phytohemagglutinin and pokeweed mitogen, of mixed-breed dogs with natural L. infantum infection, either in presymptomatic or in patent disease condition, compared to healthy animals. Leishmania antigens did not induce a clear proliferative response in any of the animals examined. Furthermore, mitogen-induced lymphocyte proliferation was found strongly reduced not only in symptomatic, but also in presymptomatic dogs suggesting that the cell-mediated immunity is suppressed in progressive canine leishmaniasis. To test this finding, naive Beagle dogs were exposed to natural L. infantum infection in a highly endemic area of southern Italy. Two to 10 months after exposure all dogs were found to be infected by Leishmania, and on month 2 of exposure they all showed a significant reduction in PBMC activation by mitogens. Our results indicate that suppression of the lymphoproliferative response is a common occurrence in dogs already at the beginning of an established leishmanial infection. # 1999 Elsevier Science B.V. All rights reserved

Differences and similarities between SARS-CoV and SARS-CoV-2: spike receptor-binding domain recognition and host cell infection with support of cellular serine proteases

Novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) became pandemic by the end of March 2020. In contrast to the 2002–2003 SARS-CoV outbreak, which had a higher pathogenicity and lead to higher mortality rates, SARSCoV-2 infection appears to be much more contagious. Moreover, many SARS-CoV-2 infected patients are reported to develop low-titer neutralizing antibody and usually suffer prolonged illness, suggesting a more effective SARS-CoV-2 immune surveillance evasion than SARS-CoV. This paper summarizes the current state of art about the differences and similarities between the pathogenesis of the two coronaviruses, focusing on receptor binding domain, host cell entry and protease activation. Such differences may provide insight into possible intervention strategies to fight the pandemic

Nonequilibrium Quantum Thermodynamics of a Particle Trapped in a Controllable Time-Varying Potential

Many advanced quantum techniques feature non-Gaussian dynamics, and the ability to manipulate the system in that domain is the next stage in many experiments. One example of meaningful non-Gaussian dynamics is that of a double-well potential. Here we study the dynamics of a levitated nanoparticle undergoing the transition from a harmonic potential to a double well in a realistic setting, subjected to both thermalization and localization. We characterize the dynamics of the nanoparticle from a thermodynamic point of view, investigating the dynamics with the Wehrl entropy production and its rates. Furthermore, we investigate coupling regimes where the the quantum effect and thermal effect are of the same magnitude, and look at suitable squeezing of the initial state that provides the maximum coherence. The effects and the competitions of the unitary and the dissipative parts onto the system are demonstrated. We quantify the requirements to relate our results to a bonafide experiment with the presence of the environment, and discuss the experimental interpretations of our results in the end