Supersymmetry Breaking and Gravitino Production after Inflation in Modular Invariant Supergravity

By using a string-inspired modular invariant supergravity, which was proved well to explain WMAP observations appropriately, a mechanism of supersymmetry breaking (SSB) and Gravitino Production just after the end of inflation are investigated. Supersymmetry is broken mainly by F-term of the inflaton superfield and the Goldstino is identified to be inflatino in this model, which fact is shown numerically. By using the canonically normalized and diagonalized scalars, the decay rates of these fields are calculated, for both the $T$ and $Y$ into gravitinos. Non-thermal production of gravitinos is not generated from the inflaton (dilaton), since the inflaton mass is lighter than gravitino, but they are produced by the decay of modular field $T$ and scalar field $Y$. Because the reheating temperature $T_R$ is about order $\sim O(10^{10})$ GeV and the mass of gravitino is $3.16 \times 10^{12}$ GeV, it is not reproduced after the reheating of the universe. The gravitinos are produced almost instantly just after the end of inflation through $Y$ and $T$, not from inflaton. Because the decay time appears very rapid, gravitinos disappear before the BBN stage of the universe. The effects of the lightest supersymmetric particles (LSP) produced by gravitinos may be important to investigate more carefully, if the LSP's are the candidate of dark matter.Comment: 11 pages, 1 figure

Dilatonic Inflation, Gravitino and Reheating in Modified Modular invariant Supergravity

A new modified string-inspired modular invariant supergravity model is proposed and is applied to realize the slow roll inflation in Einstein frame, so that the model explains WMAP observations very well. Gravitino mass and their production rate from scalar fields are estimated at certain values of parameters in the model. Seven cases of parameter choices are discussed here, among which some examples show the possibility of observation of gauginos by LHC experiments, which will give some hints of identity of dark matters. The reheating temperature, which is estimated by the stability condition of Boltzmann equation by using the decay rates of the dilaton $S$ into gauginos, is lower than the mass of gravitino. Therefore no thermal reproduction of gravitinos happens. The ratio between the scalar and tensor power spectrum is predicted to be almost the same for the seven cases under study, and its value $r \sim 6.8 \times 10^{-2}$ seems in the range possibly observed by the Planck satellite soon. The plausible supergravity model of inflation, which will be described here, will open the hope to construct a realistic theory of particles and cosmology in this framework, including yet undetected objects.Comment: 12 pages, 4 figures, 2 table

Angular Power Spectrum in Modular Invariant Inflation Model

We propose a scalar potential of inflation, motivated by modular invariant supergravity, and compute the angular power spectra of the adiabatic density perturbations that result from this model. The potential consists of three scalar fields, S, Y and T, together with two free parameters. By fitting the parameters to cosmological data at the fixed point T=1, we find that the potential behaves like the single-field potential of S, which slowly rolls down along the minimized trajectory in Y. We further show that the inflation predictions corresponding to this potential provide a good fit to the recent three-year WMAP data, e.g. the spectral index n_s = 0.951. The TT and TE angular power spectra obtained from our model almost completely coincide with the corresponding results obtained from the \LambdaCDM model. We conclude that our model is considered to be an adequate theory of inflation that explains the present data, although the theoretical basis of this model should be further explicated.Comment: 8 pages, 8 figures and 1 tabl

Transforming growth factor α protects against Fas-mediated liver apoptosis in mice

AbstractThe Fas/Fas ligand interaction plays a crucial role in various liver diseases, and administration of agonistic anti-Fas antibody to mice causes massive hepatic apoptosis and fulminant hepatic failure. Several growth factors have recently been found to function in preventing apoptosis. In this study, we demonstrated that overexpression of transforming growth factor α (TGFα) has a dramatic protective effect on Fas-mediated hepatic apoptosis at the biochemical and histological levels. Moreover, 85.7% (six out of seven) of TGFα transgenic mice survived the lethal liver damage, whereas all wild-type mice died. Expression of Bcl-xL, an anti-apoptotic protein, was greatly increased in the transgenic mice. Taken together, our findings suggest that TGFα protects against Fas-mediated liver apoptosis in vivo and up-regulation of Bcl-xL may participate in protective effect of TGFα

Effects of ultradian variation on smoking behavior

The purpose of this study is to examine the enhancement model of smoking maintenance, which has been proposed by Mangan & Golding (1978). We studied the relationships of the ultradian variations among the smoking behavior and sleepiness. The results were as follows. (1) The results of the time series analysis revealed that several spectral peaks were obtained in day time fluctuations of smoking behavior, sleepiness, mood and task performance. The average peak frequency for each parameter distributed in the range of 10 to 14 cycle/day (c/d : See Fig. 3-6). (2) The significant correlations were obtained between the parameters of the smoking behavior (frequency of puffing and VAS score of need for smoking) and the daytime sleepiness (VAS score). The significant average correlation coefficients between smoking need and sleepiness were observed (See Table 2). In general, present results agree with the enhancement model of smoking maintenance

Effect of Digestibility of Soy Protein Concentrate on Rat Nutrition(1) : Effect of Proteolytic Pretreatment of Soy Protein Concentrate on Amino Acid Pattern in Small Intestine and Activities of Enzymes related with Digestion and Metabolism of Protein

The digestion and metabolism of protein of rats fed soy protein concentrate (SP) pretreated by protease was investigated, and the nutritive value of the pretreated SP was discussed. Glutamate-pyruvate transaminase, arginase and xanthine oxidase activities in liver of rats fed heated SP are lower than those fed SP pretreated by protease and amino acid mixture simulated SP. There is more quantity of peptide in small intestine of rats fed SP pretreated by protease than that fed the amino acid mixture. In free amino acid pattern, however, no difference was shown between SP groups, but the patterns of SP groups, especially on the bases of methionine content, were different with that of amino acid mixture group. No difference is shown in the digestion and the biological values between SP groups. From these results, it was found that the pretreatment of SP by protease, which might improve the digestibility of SP, was effective for raising the availability of SP. It may be considered, furthermore, that methionine in SP is difficult to liberate in small intestine, which causes a wasteful absorption of amino acids for rat

Overexpression of hepatocyte growth factor/scatter factor promotes vascularization and granulation tissue formation in vivo

AbstractThe effect of hepatocyte growth factor/scatter factor (HGF/SF) during wound healing in the skin was investigated, using HGF/SF-overexpressing transgenic mouse model. Histological analysis of HGF/SF transgenic mouse excisional wound sites revealed increased granulation tissue with marked vascularization. Northern blot analysis demonstrated that, relative to control, vascular endothelial growth factor (VEGF) expression in transgenic skin was significantly higher at baseline and was robustly up-regulated during wound healing. Elevated levels of VEGF protein were detected immunohistochemically, predominantly in endothelial cells and fibroblasts within the granulation tissue of HGF/SF transgenic skin. Serum levels of VEGF were also elevated in HGF/SF transgenic mice. Thus, results from our study suggest that HGF/SF has a significant effect on vascularization and granulation tissue formation during wound healing in vivo, involving with induction of VEGF

Energy transfer from Cr to Nd in substitutional crystal Y3GaxAl5-x O12 codoped with Nd and Cr

Garnet crystals codoped with Nd3+ and Cr3+ ions are a candidate for solar-pumped laser materials. Substitutional disordered crystals Y3GaxAl5-xO12 were prepared to improve the pumping efficiency of Nd3+ luminescence and energy transfer from Cr3+ to Nd3+ ions. The substitutional disordered crystal host produced inhomogeneous broadening of the Nd3+ and Cr3+ optical spectra. Enhancement of overlapping between the Cr3+ absorption bands and the solar spectrum, and between the Cr3+ luminescence bands and the Nd3+ absorption lines led to the increases of the pumping efficiency and the energy transfer rates, respectively. The excitation spectrum of the Nd3+ luminescence, the nonexponential decay curves of the Cr3+ luminescence, and the quantum yields of the Cr3+ and Nd3+ luminescence have given evidence on the energy transfer from Cr3+ to Nd3+ ions