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We present a new model for time evolution of fast magnetic reconnection in free space, which is characterized by self-similarity. Reconnection triggered by locally enhanced resistivity assumed at the center of the current sheet can self-similarly and unlimitedly evolve until external factors affect the evolution. The possibility and stability of this type of evolution are verified by numerical simulations in a very wide spatial dynamic range. Actual astrophysical reconnection in solar flares and geomagnetospheric substorms can be treated as an evolutionary process in free space, because the resultant scale is much larger than the initial scale. In spite of this fact, most of the previous numerical works focused on the evolutionary characters strongly affected by artificial boundary conditions on the simulation boundary. Our new model clarifies a realistic evolution for such cases. The characteristic structure around the diffusion region is quite similar to the Petschek model which is characterized by a pair of slow-mode shocks and the fast-mode rarefaction-dominated inflow. However, in the outer region, a vortex-like return flow driven by the fast-mode compression caused by the piston effect of the plasmoid takes place. The entire reconnection system expands self-similarly.

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In the 1991-strain of Aquarius paludum in Kochi, both critical photoperiods for wing-form and diapause shifted to longer values by 1 h when specimens were grown under gradually decreasing photoperiods. However, the 1999-strain didn't respond at all to decreasing (14.5L to 13.5L) or increasing (12.5L to 13.5L) photoperiods. Photoperiodic response for wing-form determination by the 2002-strain was witnessed only in a small range between 60% and 95% as the proportion of long-winged form, and the critical photoperiod (14L) was a little bit longer than the critical value of 13.75L for the 1991-strain. The critical photoperiod for diapause induction in the 2002-strain was estimated to be 13

In the present study, we measured the levels of the cytokines and gelatinase species in the fluids of ameloblastomas and odontogenic keratocysts, and showed that ameloblastomas can be distinguished from odontogenic keratocysts by the use of these biochemical data. We found that interleukin (IL)-1alpha and IL-1beta levels in the intracystic fluids of ameloblastomas were significantly lower than those in the fluids of odontogenic keratocysts, while IL-6 levels in the fluids of ameloblastomas were significantly higher than those in the fluids of odontogenic keratocysts. On the other hand, no significant differences in tumor necrosis factor (TNF)-alpha levels of the fluids were detected between ameloblastomas and odontogenic keratocysts. An immunohistochemical study revealed that the staining intensity of IL-1alpha, IL-1beta and TNF-alpha in the tumor cells of ameloblastomas was significantly weaker than that in the epithelial cells of odontogenic keratocysts, while the staining intensity of IL-6 in the tumor cells was significantly stronger than that in the epithelial cells of odontogenic keratocysts. Gelatin zymography of the fluids showed that only a small amount of pro-MMP-9 was detected in ameloblastomas, while both pro-MMP-9 and the active form of MMP-9 were detected in 8 of 10 cases of odontogenic keratocysts. Thus, ameloblastomas can be distinguished from odontogenic keratocysts by measuring IL-1alpha and IL-6 levels, and gelatinase species in the fluids.

We have clarified the structure of asymmetric magnetic reconnection in detail as the result of the spontaneous evolutionary process. The asymmetry is imposed as ratio k of the magnetic field strength in both sides of the initial current sheet (CS) in the isothermal equilibrium. The MHD simulation is carried out by the HLLD code for the long-term temporal evolution with very high spatial resolution. The resultant structure is drastically different from the symmetric case (e.g., the Petschek model) even for slight asymmetry k = 2. (1) The velocity distribution in the reconnection jet clearly shows a two-layered structure, i.e., the high-speed sub-layer in which the flow is almost field aligned and the acceleration sub-layer. (2) Higher beta side (HBS) plasma is caught in a lower beta side plasmoid. This suggests a new plasma mixing process in the reconnection events. (3) A new large strong fast shock in front of the plasmoid forms in the HBS. This can be a new particle acceleration site in the reconnection system. These critical properties that have not been reported in previous works suggest that we contribute to a better and more detailed knowledge of the reconnection of the standard model for the symmetric magnetic reconnection system.

We have classified possible transonic solutions of galactic outflows in the gravitational potential of the dark matter halo (DMH) and super massive black hole (SMBH) under the assumptions of isothermal, spherically symmetric and steady state. It is clarified that the gravity of SMBH adds a new branch of transonic solutions with the transonic point in very close proximity to the centre in addition to the outer transonic point generated by the gravity of DMH. Because these two transonic solutions have substantially different mass fluxes and starting points, these solutions may have different influences on the evolution of galaxies and the release of metals into intergalactic space. We have applied our model to the Sombrero galaxy and obtained a new type of galactic outflow: a slowly accelerated transonic outflow through the transonic point at very distant region (≃ 126 kpc). In this galaxy, previous works reported that although the trace of the galactic outflow is observed by X-ray, the gas density distribution is consistent with the hydrostatic state. We have clarified that the slowly accelerating outflow has a gas density profile quite similar to that of the hydrostatic solution in the widely spread subsonic region. Thus, the slowly accelerating transonic solution cannot be distinguished from the hydrostatic solution in the observed region ( 25 kpc) even if slow transonic flow exists. Our model provides a new perspective of galactic outflows and is applicable even to quiescent galaxies with inactive star formation.