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The ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) Mini-Array will be composed of nine imaging atmospheric Cherenkov telescopes at the Observatorio del Teidesite. The array will be best suited for astrophysical observations in the 0.3–200 TeV range with an angular resolution of few arc-minutes and an energy resolution of 10-15%. A core-science programme in the first four years will be devoted to a limited number of key targets, addressing the most important open scientific questions in the very-high energy domain. At the same time, thanks to a wide field of view of about 10∘, ASTRI Mini-Array will observe many additional field sources, which will constitute the basis for the long-term observatory programme that will eventually cover all the accessible sky. In this paper, we review different astrophysical Galactic environments, e.g. pulsar wind nebulae, supernova remnants, and gamma-ray binaries, and show the results from a set of ASTRI Mini-Array simulations of some of these field sources made to highlight the expected performance of the array (even at large offset angles) and the important additional observatory science that will complement the core-science program.

Flux-dominated solar dynamo models, which have been demonstrated to be quite successful in reproducing most of the observed features of the large-scale solar magnetic cycle, generally produce an inappropriate latitudinal distribution of the toroidal magnetic fields, showing fields of large magnitude in polar regions where the radial shear has a maximum amplitude. Employing a kinematic solar dynamo model, here we explore the contributions of both the radial and the latitudinal shear in the generation of the toroidal magnetic fields by varying the shape and the thickness of the solar tachocline. We also explore the effects of the diffusivity profile of the convective zone. Considering the shear term of the dynamo equation, $(\vec{B}_{\rm p} \cdot \nabla) \Omega =B_r{\partial \Omega/\partial r}+ B_{\theta}/r \, \partial \Omega / \partial \theta$, we find that the latitudinal component is always dominant over the radial component at producing toroidal field amplification. These results are very sensitive to the adopted diffusivity profile, specially in the inner convection zone (which is characterized by the diffusivity $\eta_{\rm c}$and the radius rcof transition between a weak and a strong turbulent region). A diagram of the toroidal field at a latitude of $60^{\circ}$versus the diffusivity at the convection layer for different values of the tachocline width has revealed that these fields are mainly eliminated for tachoclines with width $d_1 \gtrsim 0.08~R_{\odot}$(for $\eta_{\rm c} \simeq 2\times10^9 {-} 1\times10^{10}$cm2s-1and $r_{\rm c} = 0.715~R_{\odot}$), or for $d_1 \lesssim 0.02~R_{\odot}$and almost any value of $\eta_{\rm c}$in the appropriate solar range. For intermediate values of $d_1 \simeq 0.04~R_{\odot}$-$0.06~R_{\odot}$, strong toroidal fields should survive at high latitudes in the butterfly diagram and those values are therefore not suitable. We have built butterfly diagrams for both a thin and a thick tachocline that best match the observations. We have also found that a prolate tachocline is able to reproduce solar-like butterfly diagrams depending on the choice of appropriate diffusivity profiles and tachocline width range.

Recent observational studies of the age distribution of star clusters in nearby merging galaxies and starburst (SB) galaxies indicate a premature death of the young clusters. The fate of an evolving star cluster crucially depends of its gas content. This behaves like a glue that helps to keep the star system gravitationally bound. In SB systems where the rate of supernovae (SNe) explosions is elevated one should expect an efficient heating of the gas and its complete removal which could then favor the rapid dissociation of the evolving star clusters. Based on a contemporaneous study of the dynamical evolution of the interstellar gas in SB environments (Melioli & de Gouveia Dal Pino 2004, A&A, 424, 817) where it has been considered also the presence of dense clouds that may inhibit the heating efficiency of the interstellar gas by the SNe, we have here computed the timescales for gas removal from young clusters embedded in these systems and found that they are consistent with the very short timescales for cluster dissolution which are inferred from the observational studies above. Our results indicate that typical SB proto-clusters should start to disperse after less than 5 Myr. For a given total gas mass content, this result is nearly insensitive to the initial star formation efficiency.

Most galaxies present supernova shock fronts interacting with cloudy interstellar medium. These interactions can occur either at small scales, between a single supernova remnant (SNR) and a compact cloud, or at large scales, between a giant shell of a superbubble and a molecular cloud. Here study the by-products of SNR-clouds in a starburst (SB) system. Due to the high supernova (SN) rate in this environment, a cloud may be shocked more than once by SNRs. These interactions can have an important role in the recycling of matter from the clouds to the ISM and vice-versa. Their study is also relevant to understand the evolution of the ISM density and the structure of the clouds embedded in it.
In the present work, we have focused our attention on the global effects of the interactions between clouds and SN shock waves in the ISM of SB environments and performed three-dimensional radiative cooling hydrodynamical simulations which have included the continuity equations for several atomic/ionic and molecular species. We have also considered the effects of the photo-evaporation due to the presence of the UV radiation from hot stars and SNe. 
The results have shown that due to the presence of radiative cooling, the interactions cause the formation of elongated cold filaments, instead of favoring an efficient mixing of the cloud gas with the diffuse ISM. These filaments could be associated with the dense clumps observed inside several SBs that are blown out by the galactic wind. The results have also revealed that the SNR-cloud interactions are less efficient at producing substantial mass loss from the clouds to the diffuse ISM than mechanisms such as the photo-evaporation caused by the UV flux from the hot stars. This result has important consequences for the global evolution of the SB environment and the formation of the associated superwinds, and may also be relevant to the ISM of normal galaxies.

We here present results of three-dimensional Smoothed Particle hydro and magnetohydrodynamics simulations of rotating jets, also including the effects of radiative cooling, precession and velocity variability. Using initial conditions and parameters which are particularly suitable for the DG Tau microjet, we have been able to approximately reproduce its complex knotty morphology and kinematics. We have also obtained radial velocity maps which are in good agreement with the data obtained by Bacciotti et al., thus indicating that their interpretation that the DG Tau microjet is rotating is correct. Finally, we have found that a magnetic field of the order of ≈0.5 mG is sufficient to collimate the jet against the lateral expansion that is caused by the centrifugal forces.

The interstellar medium heated by supernova explosions (SN) may acquire an expansion velocity larger than the escape velocity and leave the galaxy through a supersonic wind. Galactic winds are effectively observed in many local starburst galaxies. SN ejecta are transported out of the galaxies by such winds which thus affect the chemical evolution of the galaxies. The effectiveness of the processes mentioned above depends on the heating efficiency (HE) of the SNe, i.e. on the fraction of SN energy which is not radiated away. The value of HE, in particular in starburst (SB) galaxies, is a matter of debate. We have constructed a simple semi-analytic model, considering the essential ingredients of a SB environment which is able to qualitatively trace the thermalisation history of the ISM in a SB region and determine the HE evolution. Our study has been also accompanied by fully 3-D radiative cooling, hydrodynamical simulations of SNR-SNR and SNR-clouds interactions. We find that, as long as the typical time scale of mass-loss of the clouds to the ambient medium, which is often dominated by photoevaporation, remains shorter than the time scale at which the SNRs interact to form a superbubble, the SN heating efficiency remains very small, as radiative cooling of the gas dominates. If there is a continuous production of clouds by the gas swept by the SNR shells, this occurs during the first ≤16 Myr of the SB activity (of ~30 Myr), after which the efficiency rapidly increases to one, leading to a possible galactic wind formation. Under an extreme condition in which no clouds are allowed to form, other than those that were already initially present in the  SB environment, then in this case HE increases to one in only few Myr. We conclude that the HE value has a time-dependent trend that is sensitive to the initial conditions of the system and cannot be simply assumed to be ~1, as it is commonly done in most SB galactic wind models.

We present 3D, gasdynamic simulations of jet/cloud collisions, with the purpose of modelling the HH 270/110 system. From the models, we obtain predictions of Hαand H21–0 s(1) emission line maps, which qualitatively reproduce some of the main features of the corresponding observations of HH 110. We find that the model that better reproduces the observed structures corresponds to a jet that was deflected at the surface of the cloud ~1000 yr ago, but is now boring a tunnel directly into the cloud. This model removes the apparent contradiction between the jet/cloud collision model and the lack of detection of molecular emission in the crossing region of the HH 270 and HH 110 axes.

Context. The turbulent pumping effect corresponds to the transport of magnetic flux due to the presence of density and turbulence gradients in convectively unstable layers. In the induction equation it appears as an advective term and for this reason it is expected to be important in the solar and stellar dynamo processes.Aims. We explore the effects of turbulent pumping in a flux-dominated Babcock-Leighton solar dynamo model with a solar-like rotation law.Methods. As a first step, only vertical pumping has been considered through the inclusion of a radial diamagnetic term in the induction equation. In the second step, a latitudinal pumping term was included and then, a near-surface shear was included.Results. The results reveal the importance of the pumping mechanism in solving current limitations in mean field dynamo modeling, such as the storage of the magnetic flux and the latitudinal distribution of the sunspots. If a meridional flow is assumed to be present only in the upper part of the convective zone, it is the full turbulent pumping that regulates both the period of the solar cycle and the latitudinal distribution of the sunspot activity. In models that consider shear near the surface, a second shell of toroidal field is generated above r=0.95?R?at all latitudes. If the full pumping is also included, the polar toroidal fields are efficiently advected inwards, and the toroidal magnetic activity survives only at the observed latitudes near the equator. With regard to the parity of the magnetic field, only models that combine turbulent pumping with near-surface shear always converge to the dipolar parity.Conclusions. This result suggests that, under the Babcock-Leighton approach, the equartorward motion of the observed magnetic activity is governed by the latitudinal pumping of the toroidal magnetic field rather than by a large scale coherent meridional flow. Our results support the idea that the parity problem is related to the quadrupolar imprint of the meridional flow on the poloidal component of the magnetic field and the turbulent pumping positively contributes to wash out this imprint.

Flux-dominated solar dynamo models have demonstrated to reproduce the main features of the large scale solar magnetic cycle, however the use of a solar like differential rotation profile implies in the the formation of strong toroidal magnetic fields at high latitudes where they are not observed. In this work, we invoke the hypothesis of a thin-width tachocline in order to confine the high-latitude toroidal magnetic fields to a small area below the overshoot layer, thus avoiding its influence on a Babcock-Leighton type dynamo process. Our results favor a dynamo operating inside the convection zone with a tachocline that essentially works as a storage region when it coincides with the overshoot layer. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

α-Crystallin is a major chaperone lens protein to which has been ascribed antioxidant functions. In the present work we have evaluated the antioxidant and free radical scavenging properties of bovine α-crystallin in a series of in vitromodels: zimosan-induced, luminol-enhanced chemiluminescence response of polymorphonuclear leukocytes, the autoxidation of brain homogenate, bleaching of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)-derived radical cations, trapping of peroxyl radicals, and reactivity toward hypochloric acid. In all these systems, the reactivity of α-crystallin is higher than or similar to that of bovine serum albumin. It is concluded that, given the high concentrations of α-crystallin in the lenses, its capacity to interact with free radicals and to remove hypochlorous acid could contribute to the maintenance of the lens functionality.

The ASTRI Mini-Array (MA) is an INAF project to build and operate a facility to study astronomical sources emitting at very high-energy in the TeV spectral band. The ASTRI MA consists of a group of nine innovative Imaging Atmospheric Cherenkov telescopes. The telescopes will be installed at the Teide Astronomical Observatory of the Instituto de Astrofisica de Canarias (IAC) in Tenerife (Canary Islands, Spain) on the basis of a host agreement with INAF. Thanks to its expected overall performance, better than those of current Cherenkov telescopes' arrays for energies above ∼5 TeV and up to 100 TeV and beyond, the ASTRI MA will represent an important instrument to perform deep observations of the Galactic and extra-Galactic sky at these energies.

Without Abstract:

Many frogs lay their eggs in water; the development of these frogs is well-known. However, many frogs reproduce on land; their eggs are large and have an altered early development. As examples, Gastrotheca riobambae broods its embryos in a pouch on the mother's back, and Eleutherodactylus coqui exhibits direct development with no tadpole stage. We provide practical information on obtaining eggs and embryos from these terrestrial-breeding species and on analyzing their development. Our aim is to make these species more accessible to researchers who are interested in the developmental and evolutionary consequences of terrestrial development.

The serum lactic acid dehy-drogenase isoenzyme pattern has been studied in 7 normal subjects, 6 patients with tropical sprue in its acute phase and 4 partially, but inadequately treated cases of tropical sprue. The results reveal a marked increase in the LD5 isoenzyme fraction which returned to normal with continuous adequate specific therapy. Since the isoenzyme abnormality does not disappear until 10-14 days after the serum lactic dehydrogenase reach a normal level, an abnormally high LD5 iso-enzyme fraction may be an indication of the lack of total correction of the abnormalities present during the acute phase of the disease. As such, this may be a sign of the need of more active therapy.

Large-scale magnetic fields created by dynamo action along with magneto-centrifugal and reconnection processes in accretion disks around the sources is currently the most accepted mechanism for jet production. Understanding the production of magnetic fields in jet-accretion phenomena may be the key for understanding the origin of the large-scale magnetic fields in galaxy clusters and in the Universe. Here, we discuss recent observational, theoretical and numerical results on jet phenomena that support the MHD scenarios for jet production. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Context. It was proposed earlier that the relativistic ejections observed in microquasars could be produced by violent magnetic reconnection episodes at the inner disk coronal region (de Gouveia Dal Pino & Lazarian 2005). Aims. Here we revisit this model, which employs a standard accretion disk description and fast magnetic reconnection theory, and discuss the role of magnetic reconnection and associated heating and particle acceleration in different jet/disk accretion systems, namely young stellar objects (YSOs), microquasars, and active galactic nuclei (AGNs).Methods. In microquasars and AGNs, violent reconnection episodes between the magnetic field lines of the inner disk region and those that are anchored in the black hole are able to heat the coronal/disk gas and accelerate the plasma to relativistic velocities through a diffusive first-order Fermi-like process within the reconnection site that will produce intermittent relativistic ejections or plasmons.Results. The resulting power-law electron distribution is compatible with the synchrotron radio spectrum observed during the outbursts of these sources. A diagram of the magnetic energy rate released by violent reconnection as a function of the black hole (BH) mass spanning 109orders of magnitude shows that the magnetic reconnection power is more than sufficient to explain the observed radio luminosities of the outbursts from microquasars to low luminous AGNs. In addition, the magnetic reconnection events cause the heating of the coronal gas, which can be conducted back to the disk to enhance its thermal soft X-ray emission as observed during outbursts in microquasars. The decay of the hard X-ray emission right after a radio flare could also be explained in this model due to the escape of relativistic electrons with the evolving jet outburst. In the case of YSOs a similar magnetic configuration can be reached that could possibly produce observed X-ray flares in some sources and provide the heating at the jet launching base, but only if violent magnetic reconnection events occur with episodic, very short-duration accretion rates which are ~100–1000 times larger than the typical average accretion rates expected for more evolved (T Tauri) YSOs.