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Both mammary gland development and mammary carcinogenesis involve extensive remodeling of the mammary gland extracellular matrix. The expression of four membrane-type matrix metalloproteinases (MT-MMPs) with matrix remodeling potential in development and tumorigenesis was evaluated by in-situ hybridization on mouse mammary gland sections. MT1-MMP and MT3-MMP were found in the mammary stroma mainly around epithelial structures in both developing and mature mammary gland. In contrast, MT2-MMP was found exclusively in the mammary epithelium. Lactating gland expressed none of the examined MT-MMPs. Mammary gland tumors expressed MT1-MMP, MT2-MMP, and MT3-MMP while MT4-MMP was not expressed in any developmental or cancerous stage analyzed here. Our results suggest that MT1-MMP, MT2-MMP, and MT3-MMP may be involved in remodeling of both the normal and diseased mammary gland either directly or indirectly by activation of other MMPs. Published 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Starburst amacrine cells in the macaque retina were studied by electron microscopic immunohistochemistry. We found that these amacrine cells make a type of synapse not described previously; they are presynaptic to axon terminals of bipolar cells. We also confirmed that starburst amacrine cells are presynaptic to ganglion cell dendrites and amacrine cell processes. In order to determine the functions of these synapses, we localized acetylcholine receptors using a monoclonal antibody (mAb210) that recognizes human α3- and α5-containing nicotinic receptors and also antisera against the five known subtypes of muscarinic receptors. The majority of the mAb210-immunoreactive perikarya were amacrine cells and ganglion cells, but a subpopulation of bipolar cells was also labeled. A subset of bipolar cells and a subset of horizontal cells were labeled with antibodies to M3 muscarinic receptors. A subset of amacrine cells, including those that contain cholecystokinin, were labeled with antibodies to M2 receptors. Taken together, these results suggest that acetylcholine can modulate the activity of retinal ganglion cells by multiple pathways. J. Comp. Neurol. 461:76–90, 2003. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Using low-temperature molecular beam epitaxy, we experimentally examine the substitutions of Fe atoms for Co ones in Co3−xFexSi (1.0≤x≤3.0) Heusler-compound films grown on Si and Ge. The Co-Fe atomic substitution at A and C sites can be confirmed by the conversion electron Mössbauer spectroscopy measurements. The magnetic moment and the magnitude of spin signals in nonlocal spin-valve measurements are systematically changed with increasing x in Co3−xFexSi. By assuming proper spin diffusion length for Co3−xFexSi on the basis of our previous work [ Phys. Rev. B 85 100404 (2012)], we experimentally verify that the Co-Fe substitution in Co3−xFexSi can directly affect the room-temperature spin polarization. [ABSTRACT FROM AUTHOR]

Neural systems are necessarily the adaptive products of natural selection, but a neural system, dedicated to any particular function in a complex brain, may be composed of components that covary with functionally unrelated systems, owing to constraints beyond immediate functional requirements. Some studies support a modular or mosaic organization of the brain, whereas others emphasize coordination and covariation. To contrast these views, we have analysed the retina, striate cortex (V1) and extrastriate cortex (V2, V3, MT, etc.) in 30 mammals, examining the area of the neocortex and individual neocortical areas and the relative numbers of rods and cones. Controlling for brain size and species relatedness, the sizes of visual cortical areas (striate, extrastriate) within the brains of nocturnal and diurnal mammals are not statistically different from one another. The relative sizes of all cortical areas, visual, somatosensory and auditory, are best predicted by the total size of the neocortex. In the sensory periphery, the retina is clearly specialized for niche. New data on rod and cone numbers in various New World primates confirm that rod and cone complements of the retina vary substantially between nocturnal and diurnal species. Although peripheral specializations or receptor surfaces may be highly susceptible to niche-specific selection pressures, the areal divisions of the cerebral cortex are considerably more conservative. [ABSTRACT FROM AUTHOR]

By combining solid phase epitaxy and molecular beam epitaxy with Sb doping, we can form n-type Ge layers on one of the ferromagnetic Heusler alloys, Fe3Si. Two-dimensional epitaxial growth of the Sb-doped Ge layers can be achieved on the Si-terminated Fe3Si surface at 175 ◦C. Electrical properties of the Au-Ti/Sb-doped Ge/Fe3Si/p-Ge/Al vertical devices indicate that the Sb-doped Ge layer is an n-type semiconductor. We also show a high-quality CoFe/n-Ge/Fe3Si trilayer structure for vertical semiconductor spintronic devices. [ABSTRACT FROM AUTHOR]

The present status of kinetic modeling of particle dynamics in hydrogen negative ion (H−) source plasmas and their comparisons with experiments are reviewed and discussed with some new results. The main focus is placed on the following topics, which are important for the research and development of H− sources for intense and high-quality H− ion beams: (i) effects of non-equilibrium features of electron energy distribution function on volume and surface H− production, (ii) the origin of the spatial non-uniformity in giant multi-cusp arc-discharge H− sources, (iii) capacitive to inductive (E to H) mode transition in radio frequency-inductively coupled plasma H− sources and (iv) extraction physics of H− ions and beam optics, especially the present understanding of the meniscus formation in strongly electronegative plasmas (so-called ion–ion plasmas) and its effect on beam optics. For these topics, mainly Japanese modeling activities, and their domestic and international collaborations with experimental studies, are introduced with some examples showing how models have been improved and to what extent the modeling studies can presently contribute to improving the source performance. Close collaboration between experimental and modeling activities is indispensable for the validation/improvement of the modeling and its contribution to the source design/development. [ABSTRACT FROM AUTHOR]

We have constructed a nuclear equation of state (EOS) that includes a full nuclear ensemble for use in core-collapse supernova simulations. It is based on the EOS for uniform nuclear matter that two of the authors derived recently, applying a variational method to realistic two- and three-body nuclear forces. We have extended the liquid drop model of heavy nuclei, utilizing the mass formula that accounts for the dependences of bulk, surface, Coulomb and shell energies on density and/or temperature. As for light nuclei, we employ a quantum-theoretical mass evaluation, which incorporates the Pauli- and self-energy shifts. In addition to realistic nuclear forces, the inclusion of in-medium effects on the full ensemble of nuclei makes the new EOS one of the most realistic EOSs, which covers a wide range of density, temperature and proton fraction that supernova simulations normally encounter. We make comparisons with the FYSS EOS, which is based on the same formulation for the nuclear ensemble but adopts the relativistic mean field theory with the TM1 parameter set for uniform nuclear matter. The new EOS is softer than the FYSS EOS around and above nuclear saturation densities. We find that neutron-rich nuclei with small mass numbers are more abundant in the new EOS than in the FYSS EOS because of the larger saturation densities and smaller symmetry energy of nuclei in the former. We apply the two EOSs to 1D supernova simulations and find that the new EOS gives lower electron fractions and higher temperatures in the collapse phase owing to the smaller symmetry energy. As a result, the inner core has smaller masses for the new EOS. It is more compact, on the other hand, due to the softness of the new EOS and bounces at higher densities. It turns out that the shock wave generated by core bounce is a bit stronger initially in the simulation with the new EOS. The ensuing outward propagations of the shock wave in the outer core are very similar in the two simulations, which may be an artifact, though, caused by the use of the same tabulated electron capture rates for heavy nuclei ignoring differences in the nuclear composition between the two EOSs in these computations. [ABSTRACT FROM AUTHOR]

We develop a low-temperature growth technique of epitaxial Ge layers on a body-centered-cubic ferromagnetic metal (bcc-FM), Fe3Si, by combining solid phase epitaxy (SPE) and molecular beam epitaxy (MBE). The insertion of an SPE-grown Ge layer enables two-dimensional epitaxial growth of Ge layers by MBE even at a growth temperature of ∼175 C. Thanks to the relatively flat surface of the Ge epilayers, we can obtain an epitaxial CoFe (bcc-FM) layer on top of the Ge layers, leading to the all-epitaxial CoFe/Ge/Fe3Si trilayer with a reasonable magnetization reversal process. We believe that the all-epitaxial CoFe/Ge/Fe3Si trilayer has great potential to be utilized as novel vertical-type Ge-channel spintronic devices. [ABSTRACT FROM AUTHOR]

We investigate the criterion for the acoustic mechanism to work successfully in core-collapse supernovae. The acoustic mechanism is an alternative to the neutrino-heating mechanism. It was proposed by Burrows et al., who claimed that acoustic waves emitted by g-mode oscillations in proto-neutron stars (PNS) energize a stalled shock wave and eventually induce an explosion. Previous works mainly studied to which extent the g-modes are excited in the PNS. In this paper, on the other hand, we investigate how strong the acoustic wave needs to be if it were to revive a stalled shock wave. By adding the acoustic power as a new axis, we draw a critical surface, which is an extension of the critical curve commonly employed in the context of neutrino heating. We perform both 1D and 2D parametrized simulations, in which we inject acoustic waves from the inner boundary. In order to quantify the power of acoustic waves, we use the extended Myers theory to take neutrino reactions into proper account. We find for the 1D simulations that rather large acoustic powers are required to relaunch the shock wave, since the additional heating provided by the secondary shocks developed from acoustic waves is partially canceled by the neutrino cooling that is also enhanced. In 2D, the required acoustic powers are consistent with those of Burrows et al. Our results seem to imply, however, that it is the sum of neutrino heating and acoustic powers that matters for shock revival. [ABSTRACT FROM AUTHOR]

Cascade Si LVV Auger electron spectra at the photoexcitation of the Si 1s electron in a SiCl4 molecule have been measured using an electron spectrometer combined with monochromatized undulator radiation. In the instance of the resonant excitation of the Si 1s electron into the vacant molecular orbital a peak with high yield is observed at about 106 eV, an energy considerably higher than the energies of the normal LVV Auger electron. This peak is presumed to originate from the participator decay from the state with two 2p holes and one excited electron into the state with one 2p hole and one valence hole. Following the normal KL23L23 Auger transition, the cascade spectrum shows several peak structures, e.g. 63 eV, 76 eV and 91 eV. The peak at 91 eV is probably assigned to the second step Auger decay into states having a 2p hole together with two valence holes. These findings are similar to experimental results of SiF4. The former two peaks (63 eV and 76 eV) are ascribed to Auger transitions of Si atomic ions produced through molecular ion dissociation after the first step cascade decays, although the peak heights of atomic ions are lower than those of SiF4. [ABSTRACT FROM AUTHOR]