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We studied thermal evolution of isolated neutron stars (NSs) including the pion condensation core, with an emphasis on the stiffness of equation of state (EOS). Many temperature observations can be explained by the minimal cooling scenario which excludes the fast neutrino cooling process. However, several NSs are cold enough to require it. The most crucial problem for NS cooling theory is whether the nucleon direct Urca (DU) process is open. The DU process is forbidden if the nucleon symmetry energy is significantly low. Hence, another fast cooling process is required in such an EOS. As the candidate to solve this problem, we consider the pion condensation. We show that the low-symmetry-energy model can account for most cooling observations including cold NSs, with strong neutron superfluidity. Simultaneously, it holds the $2~M_{\odot}$ observations even if the pion condensation core exists. Thus, we propose the possibility of pion condensation, as an exotic state to solve the problem in low-symmetry-energy EOSs. We examined the consistency of our EOSs with other various observations as well., 21 pages, 8 figures, accepted by Int. J. Mod. Phys. E

We calculate the abundances of 7Li, 11B, 92Nb, 98Tc, 138La, and 180Ta produced by neutrino (ν)-induced reactions in a core-collapse supernova explosion. We consider the modification by ν self-interaction (ν-SI) near the neutrinosphere and the Mikheyev–Smirnov–Wolfenstein (MSW) effect in the outer layers based on time-dependent neutrino energy spectra. Abundances of 7Li and the heavy isotopes 92Nb, 98Tc, and 138La are reduced by a factor of 1.5–2.0 by the ν-SI. In contrast, 11B is relatively insensitive to the ν-SI. We find that the abundance ratio of heavy to light nuclei, 138La/11B, is sensitive to the neutrino mass hierarchy, and the normal mass hierarchy is more likely to be consistent with the solar meteoritic abundances.

We review the recent progress in the Big-Bang nucleosynthesis which includes the standard and nonstandard theory of cosmology, effects of neutrino degeneracy, and inhomogeneous nucleosynthesis within the framework of a Friedmann model. As for a nonstandard theory of gravitation, we adopt a Brans–Dicke theory which incorporates a cosmological constant. We constrain various parameters associated with each subject.

Aspergillus niger and its related species, known as Aspergillus section Nigri , are ubiquitously distributed across the globe and are often isolated from clinical specimens. In Japan, Aspergillus section Nigri is second most often isolated from clinical specimens following Aspergillus fumigatus . We determined the species of Aspergillus section Nigri isolated in Japan by DNA sequencing of partial β-tubulin genes and investigated drug susceptibility by the CLSI M38-A2 method. The collection contained 20 Aspergillus niger , 59 Aspergillus welwitschiae , and 39 Aspergillus tubingensis strains. Drug susceptibility testing revealed 30 to 55% of A. niger , 6.8 to 18.6% of A. welwitschiae , and 79.5 to 89.7% of A. tubingensis isolates to be less susceptible (so-called resistant) to itraconazole (ITC) and/or voriconazole (VRC) according to the epidemiologic cutoff values (ECVs) proposed for A. niger previously. MIC distributions of ITC or VRC showed no remarkable differences between clinical and environmental isolates. When the cyp51A sequences were compared between susceptible and resistant strains, 18 amino acid mutations were specific for resistant isolates of A. niger and A. tubingensis ; however, none of them were confirmed to be associated with azole resistance. Three nonrelated A. welwitschiae isolates possessed a partial deletion in cyp51A , likely attributable to being more susceptible to azoles than other isolates. One of five ITC-resistant A. tubingensis isolates showed higher expression of cyp51A than did susceptible strains. Our results show that cyp51A point mutations may have no association with azole resistance but that in some cases the overexpression of cyp51A may lead to the azole resistance in these species.

MAXI J0556-332 is the hottest transient accreting neutron star at the beginning of its quiescence. A theoretical model with crustal heating indicates that an additional shallow heat source of Qshallow > 6 MeV per accreted nucleon is required in the shallow outer crust with respect to the deeper star crust by considering the observed decline in accretion rate at the end of outburst. However, the physical source of this shallow heating is still unclear. In the present investigation, we performed stellar evolutionary calculations, adopting the effects of outburst behavior of the accretion rate. As a consequence, we find that the quiescent light curve of MAXI J0556-332 can be well explained by the nuclear energy generation due to the hot CNO cycle., 9 pages, 2 figures

This paper describes an exploratory study on the effects of temperature on the formation of oxide film and rolling contact fatigue life in hydrogen, argon and air. Rolling contact fatigue tests were conducted at 333 K and 363 K by using a three-ball-on-disk type apparatus. The rolling contact fatigue life in hydrogen was shorter than that in argon, and life in air was the longest. Relationship was found between fatigue life and hydrogen concentration in steel. Cross sections of the specimens show that iron oxide grew to larger grain size in the subsurface in hydrogen environment, which may have resulted in shorter fatigue life. It was also found that fatigue failure occurs on ball surface in hydrogen at 363 K.

Comparing the latest observed abundances of 4He and D, we make a ?2 analysis to see whether it is possible to reconcile primordial nucleosynthesis using up-to-date nuclear data of NACRE II and the mean-life of neutrons. If we adopt the observational data of ${}^4_{}$He by Izotov et al., we find that it is impossible to get reasonable concordance against the standard Big-Bang nucleosynthesis. However, including degenerate neutrinos, we have succeeded in obtaining consistent constraints between the neutrino degeneracy and the baryon-to-photon ratio from detailed comparison of calculated abundances with the observational data of ${}^4_{}$He and D: the baryon-to-photon ratio in units of $10^{-10}$ is found to be in the range 6.02 < $��^{}_{10}$ < 6:54 for the specified parameters of neutrino degeneracy., 4 figures

We investigate the r-process nucleosynthesis during the magnetohydrodynamical (MHD) explosion of a supernova in a helium star of 3.3 M⊙, where effects of neutrinos are taken into account using the leakage scheme in the two-dimensional (2D) hydrodynamic code. Jet-like explosion due to the combined effects of differential rotation and magnetic field is able to erode the lower electron fraction matter from the inner layers. We find that the ejected material of low electron fraction responsible for the r-process comes out from just outside the neutrino sphere deep inside the Fe-core. It is found that heavy element nucleosynthesis depends on the initial conditions of rotational and magnetic fields. In particular, the third peak of the distribution is significantly overproduced relative to the solar system abundances, which would indicate a possible r-process site owing to MHD jets in supernovae.

Angle-resolved photoemission spectroscopy using tunable low energy photons allows us to study the quasi-particle (QP) dispersions of the inner and outer CuO2 planes (IP and OP) separately in the tri-layer cuprate Bi$_2$Sr$_2$Ca$_2$Cu$_3$O$_{10+\delta}$ (Bi2223). The kink energy of the OP band is $\sim$ 70 meV, as observed in various high-$T_c$ cuprates, while that of the IP band is as large as 100 meV in the superconducting (SC) state. This large kink energy is attributed to the $\sim$ 35 meV buckling mode plus the large ($\sim$ 60 meV) SC gap of IP. The IP band also shows a weak kink feature at 70 meV in the SC state. The latter feature can be explained either by the 70 meV half-breathing mode or by the $\sim$ 35 meV buckling-phonon mode plus the $\sim$ 40 meV SC gap of OP if interlayer scattering of QP is involved., Comment: 5 pages, 2 figures

Effects of a new triple-{\alpha} reaction rate on the s-process during the evolution of a massive star of 25 M\odot are investigated for the first time. Although the s-process in massive stars has been believed to be established with only minor change, we find that the s-process with use of the new rate during the core He-burning is very inefficient compared to the case with the previous triple-{\alpha} rate. However, the difference of the overproduction is found to be largely compensated by the subsequent C-burning. Since the s-process in massive stars has been attributed so far to the neutron irradiation during core He-burning, our finding reveals the importance of C-burning for the s-process during the evolution of massive stars., Comment: 8 pages, 5 figures. Submitted to Prog. Theor. Phys. Letters on October 2, 2011

Effects of a new triple-alpha reaction rate on the ignition of carbon-oxygen white dwarfs accreting helium in a binary systems have been investigated. The ignition points determine the properties of a thermonuclear explosion of a Type Ia supernova. We examine the cases of different accretion rates of helium and different initial masses of the white dwarf, which was studied in detail by Nomoto. We find that for all cases from slow to intermediate accretion rates, nuclear burnings are ignited at the helium layers. As a consequence, carbon deflagration would be triggered for the lower accretion rate compared to that of $dM/dt\simeq 4\times10^{-8} M_{\odot} \rm yr^{-1}$ which has been believed to the lower limit of the accretion rate for the deflagration supernova. Furthermore, off-center helium detonation should result for intermediate and slow accretion rates and the region of carbon deflagration for slow accretion rate is disappeared., 4 pages, 2 figures

We constrain the thermal evolution of the universe with a decaying cosmological term by using the method of the analysis for the Wilkinson Microwave Anisotropy Probe (WMAP) observation data. The cosmological term is assumed to be a function of the scale factor that increases toward the early universe, and the radiation energy density is lower compared to that in the model with the standard cosmological constant ($\ensuremath{\Lambda}\mathrm{CDM}$). The decrease in the radiation density affects the thermal history of the universe; e.g. the photon decoupling occurs at higher-$z$ compared to the case of the standard $\ensuremath{\Lambda}\mathrm{CDM}$ model. As a consequence, a decaying cosmological term affects the cosmic microwave background (CMB) anisotropy. Thanks to the Markov-Chain Monte Carlo method, we compare the angular power spectrum in the decaying $\ensuremath{\Lambda}\mathrm{CDM}$ model with the CMB data, and we get severe constraints on parameters of the model.

The thermal evolution of isolated neutron stars depends on neutrino emission process, equation of state (EOS) of nuclear matter, and surface composition. Focusing on the neutrino emission process, we can classify the cooling models in two groups. First one is the “standard cooling model”, which includes modified URCA process and bremsstrahlung process; these processes are believed to operate inside neutron stars. Others include some exotic processes at high density or high temperature, such as pion condensation or quark beta decay, which is named as “exotic cooling model”. Since exotic models result in high neutrino emission, exotic neutron stars cool much faster than standard ones. We investigate the thermal evolution of isolated neutron stars, using both the standard and the exotic cooling processes, and two kinds of surface composition, He and Fe. Furthermore we employ nucleon superfluidity models, and adopt a critical temperature as a density-independent parameter. We find that there exist parameter regions which can be consistent with the observational results.

For the rst time heavy element nucleosynthesis in the magneto‐hydrodynamical (MHD) explosions of core‐collapse supernovae are investigated using a massive star of 13M⊙ in a main sequence stage. Contrary to the case of the spherical explosion, jet‐like explosion due to the combined effects of the rotation and magnetic eld lowers the electron fraction signicantly inside the layers above the Fe‐core. Then, the anisotropic shock waves pass through the oxygen rich layers. As a consequence, we nd that the nucleosynthesis of the r‐ and p‐process proceeds appreciably compared to the models previously considered.

We present a new astrophysical site of the big bang nucleosynthesis (BBN) that are very peculiar compared with the standard BBN. Some models of the baryogenesis suggest that very high baryon density regions were formed in the early universe. On the other hand, recent observations suggest that heavy elements already exist in high red-shifts and the origin of these elements become a big puzzle. Motivated by these, we investigate BBN in very high baryon density regions. BBN proceeds in proton-rich environment, which is known to be like the p-process. However, by taking very heavy nuclei into account, we find that BBN proceeds through both the p-process and the r-process simultaneously. P-nuclei such as 92Mo, 94Mo, 96Ru, 98Ru whose origin is not well known are also synthesized., 6 pages, 7 figures

We present a scenario of formation of strange stars due to spin-down of {\it rapidly rotating} neutron stars left after supernova explosions . By assuming a process where the total baryon mass is conserved but the angular momentum is lost due to emission of gravitational waves and/or the magnetic braking, we find that the transition from rapidly rotating neutron stars to slowly rotating strange stars is possible; a large amount of energy $\sim 10^{53} ergs $ could be released. The liberated energy might become a new energy source for a delayed explosion of supernova. Furthermore, our scenario suggests that the supernova associated with gamma-ray bursts could become candidates for targets in the future observation of gravitational waves., 11 pages, 3 figures, Received November 5, 2004

Nucleosynthesis in ONeMg novae has been investigated with the wide ranges of three parameters, i.e., the white dwarf mass, the envelope mass at ignition, and the initial composition. A quasi-analytic one-zone approach is used with an up-to-date nuclear reaction network. The nucleosynthesis results show correlation with the peak temperatures or the cooling timescales during outbursts. Among the combinations of white dwarf and envelope masses which give the same peak temperature, the explosion is more violent for a lower white dwarf mass owing to its smaller gravitational potential. Comparison of the nucleosynthesis results with observations implies that at least two-third of the white dwarf masses for the observed ONeMg novae are $\simeq 1.1 M_\odot$, which are significantly lower than estimated by previous hydrodynamic studies but consistent with the observations of V1974 Cyg. Moreover, the envelope masses derived from the comparison are $\gtrsim 10^{-4} M_\odot$, which are in good agreement with the ejecta masses estimated from observations but significantly higher than in previous hydrodynamic studies. With such a low mass white dwarf and a high mass envelope, the nova can produce interesting amounts of $\gamma$-ray emitters $^7$Be, $^{22}$Na, and $^{26}$Al. We suggest that V1974 Cyg has produced $^{22}$Na as high as the upper limit derived from the COMPTEL survey. In addition, a non-negligible part of the Galactic $^{26}$Al may originate from ONeMg novae, if not the major contributors. Both the future INTEGRAL survey for these $\gamma$-ray emitters and abundance estimates derived from ultraviolet, optical, and near infrared spectroscopies will impose a severe constraint on the current nova models., Comment: 21 pages, 23 figures, to appear in the Astrophysical Journal, Vol. 523, No.1, September 20, 1999; preprint with embedded images can be obtained from http://th.nao.ac.jp/~wanajo/journal/onenova.ps

We have performed 1-dimensional calculations for explosive nucleosynthesis in collapse-driven supernova and investigated its sensitivity to the initial form of the shock wave. We have found the tendency that the peak temperature becomes higher around the mass cut if the input energy is injected more in the form of kinetic energy rather than internal energy. Then, the mass cut becomes larger, and, as a result, neutron-rich matter is less included in the ejecta; this is favorable for producing the observational data compared with a previous model. Our results imply that the standard method to treat various processes for stellar evolution, such as convection and electron capture during the silicon burning stage, are still compatible with the calculation of explosive nucleosynthesis., 20 pages, 6 figures, LaTex

This is the first case of Plasmodium knowlesi infection in a Japanese traveller returning from Malaysia. In September 2012, a previously healthy 35-year-old Japanese man presented to National Center for Global Health and Medicine in Tokyo with a two-day history of daily fever, mild headaches and mild arthralgia. Malaria parasites were found in the Giemsa-stained thin blood smear, which showed band forms similar to Plasmodium malariae. Although a nested PCR showed the amplification of the primer of Plasmodium vivax and Plasmodium knowlesi, he was finally diagnosed with P. knowlesi mono-infection by DNA sequencing. He was treated with mefloquine, and recovered without any complications. DNA sequencing of the PCR products is indispensable to confirm P. knowlesi infection, however there is limited access to DNA sequencing procedures in endemic areas. The extent of P. knowlesi transmission in Asia has not been clearly defined. There is limited availability of diagnostic tests and routine surveillance system for reporting an accurate diagnosis in the Asian endemic regions. Thus, reporting accurately diagnosed cases of P. knowlesi infection in travellers would be important for assessing the true nature of this emerging human infection.