Mid-infrared luminosity as an indicator of the total infrared luminosity of galaxies

The infrared (IR) emission plays a crucial role for understanding the star formation in galaxies hidden by dust. We first examined four estimators of the IR luminosity of galaxies, L_fir (Helou et al. 1988), L_tir (Dale et al. 2001), revised version of L_tir (Dale & Helou 2002) (we denote L_tir2), and L_ir (Sanders & Mirabel 1996) by using the observed SEDs of well-known galaxies. We found that L_ir provides excellent estimates of the total IR luminosity for a variety of galaxy SEDs. The performance of L_tir2 was also found to be very good. Using L_ir, we then statistically analyzed the IRAS PSCz galaxy sample (Saunders et al. 2000) and found useful formulae relating the MIR monochromatic luminosities [L(12um) and L(25um)], and L_ir. For this purpose we constructed a subsample of 1420 galaxies with all IRAS four band (12, 25, 60, and 100um) flux densities. We found linear relations between L_ir and MIR luminosities, L(12um) and L(25um). The prediction error with 95-% confidence level is a factor of 4-5. Hence, these formulae are useful for the estimation of the total IR luminosity only from 12um or 25um observations. We further tried to make an `interpolation' formula for galaxies at 0<z<1. For this purpose we construct the formula of the relation between 15-um luminosity and the total IR luminosity. We conclude that the 15-um formula can be used as an estimator of the total IR luminosity from 24um observation of galaxies at z \simeq 0.6.Comment: A&A in press, 8 pages, 9 figures, numerical errors correcte

Virtual audio reproduced in a headrest

When virtual audio reproduction is simultaneously required in many seats, such as in aircraft or cinemas, it may be convenient to use loudspeakers mounted inside each seat's headrest. In this preliminary study, the feasibility of virtual audio reproduction in the headrest of a single seat is explored using an inversion technique to compensate for crosstalk and the synthesis of head related transfer functions. Although large changes in the magnitude of the signals reproduced at the listener's ears are observed as the listener moves their head within the headrest, informal listening tests indicate that the reproduced acoustic images are surprisingly stable in about an eighth of an arc either side of the loudspeaker positions. Not surprisingly, frontal images are more difficult to reproduce with headrest loudspeakers

Strategic vs Non-Strategic Motivations of Sanctioning

We isolate strategic and non-strategic motivations of sanctioning in a repeated public goods game. In two experimental treatments, subjects play the public goods game with the possibility to sanction others. In the STANDARD sanctions treatment, each subject learns about the sanctions received in the same round as they were assigned, but in the SECRET sanctions treatment, sanctions are announced only after the experiment is finished, removing in this way all strategic reasons to punish. We find that sanctioning is similar in both treatments, giving support for nonstrategic explanations of sanctions (altruistic punishment). Interestingly, contributions to the public good in both treatments with sanctioning are higher than when the public goods game is played without any sanctioning, irrespective of announcing the sanctions to their receivers during the play of the game, or only after the game is finished. The mere knowledge that sanctions might be assigned increases cooperation: subjects correctly expect that nonstrategic sanctioning takes place against freeriders.altruistic punishment;nonstrategic sanctions;strategic sanctions;public goods;economic experiment

Horizontal transfer between loose compartments stabilizes replication of fragmented ribozymes

The emergence of replicases that can replicate themselves is a central issue in the origin of life. Recent experiments suggest that such replicases can be realized if an RNA polymerase ribozyme is divided into fragments short enough to be replicable by the ribozyme and if these fragments self-assemble into a functional ribozyme. However, the continued self-replication of such replicases requires that the production of every essential fragment be balanced and sustained. Here, we use mathematical modeling to investigate whether and under what conditions fragmented replicases achieve continued self-replication. We first show that under a simple batch condition, the replicases fail to display continued self-replication owing to positive feedback inherent in these replicases. This positive feedback inevitably biases replication toward a subset of fragments, so that the replicases eventually fail to sustain the production of all essential fragments. We then show that this inherent instability can be resolved by small rates of random content exchange between loose compartments (i.e., horizontal transfer). In this case, the balanced production of all fragments is achieved through negative frequency-dependent selection operating in the population dynamics of compartments. This selection mechanism arises from an interaction mediated by horizontal transfer between intracellular and intercellular symmetry breaking. The horizontal transfer also ensures the presence of all essential fragments in each compartment, sustaining self-replication. Taken together, our results underline compartmentalization and horizontal transfer in the origin of the first self-replicating replicases.Comment: 14 pages, 4 figures, and supplemental materia

Star formation and dust extinction properties of local galaxies from AKARI-GALEX All-Sky Surveys: First results from most secure multiband sample from FUV to FIR

The AKARI All-Sky Survey provided the first bright point source catalog detected at 90um. Starting from this catalog, we selected galaxies by matching AKARI sources with those in the IRAS PSCz. Next, we have measured total GALEX FUV and NUV flux densities. Then, we have matched this sample with SDSS and 2MASS galaxies. By this procedure, we obtained the final sample which consists of 607 galaxies. If we sort the sample with respect to 90um, their average SED shows a coherent trend: the more luminous at 90um, the redder the global SED becomes. The M_r--NUV-r color-magnitude relation of our sample does not show bimodality, and the distribution is centered on the green valley between the blue cloud and red sequence seen in optical surveys. We have established formulae to convert FIR luminosity from AKARI bands to the total infrared (IR) luminosity L_TIR. With these formulae, we calculated the star formation directly visible with FUV and hidden by dust. The luminosity related to star formation activity (L_SF) is dominated by L_TIR even if we take into account the far-infrared (FIR) emission from dust heated by old stars. At high star formation rate (SFR) (> 20 Msun yr^-1), the fraction of directly visible SFR, SFR_FUV, decreases. We also estimated the FUV attenuation A_FUV from FUV-to-total IR (TIR) luminosity ratio. We also examined the L_TIR/L_FUV-UV slope (FUV- NUV) relation. The majority of the sample has L_TIR/L_FUV ratios 5 to 10 times lower than expected from the local starburst relation, while some LIRGs and all the ULIRGs of this sample have higher L_TIR/L_FUV ratios. We found that the attenuation indicator L_TIR/L_FUV is correlated to the stellar mass of galaxies, M*, but there is no correlation with specific SFR (SSFR), SFR/M*, and dust attenuation L_TIR/L_FUV. (abridged)Comment: 13 pages, 18 figures, accepted for publication in A&

Game-theoretic versions of strong law of large numbers for unbounded variables

We consider strong law of large numbers (SLLN) in the framework of game-theoretic probability of Shafer and Vovk (2001). We prove several versions of SLLN for the case that Reality's moves are unbounded. Our game-theoretic versions of SLLN largely correspond to standard measure-theoretic results. However game-theoretic proofs are different from measure-theoretic ones in the explicit consideration of various hedges. In measure-theoretic proofs existence of moments are assumed, whereas in our game-theoretic proofs we assume availability of various hedges to Skeptic for finite prices

Planets opening dust gaps in gas disks

We investigate the interaction of gas and dust in a protoplanetary disk in the presence of a massive planet using a new two-fluid hydrodynamics code. In view of future observations of planet-forming disks we focus on the condition for gap formation in the dust fluid. While only planets more massive than 1 Jupiter mass (MJ) open up a gap in the gas disk, we find that a planet of 0.1 MJ already creates a gap in the dust disk. This makes it easier to find lower-mass planets orbiting in their protoplanetary disk if there is a significant population of mm-sized particles.Comment: 5 pages, 3 figures, accepted for publication in A&A Letter

Effect of Chondroitinases on the Growth of Solid Ehrlich Ascites Tumour

The effect of various glycosidases on the growth of solid hypotetraploid Ehrlich ascites tumour was investigated. The purified bacterial chondroitinase-ABC significantly inhibited the growth of tumour; chondroitinase-AC inhibited the tumour to some extent but chondro-4-sulphatase, chondro-6-sulphatase, streptomyces hyaluronidase, and β-glucuronidase had no inhibitory effect. Heat-treated chondroitinase-ABC had no inhibitory effect on the tumour growth. The growth of tumour cells which were injected subcutaneously after in vitro incubation with chondroitinase-ABC or -AC solution was decreased when compared with that of sham-treated cells

Effect of chondroitin sulphate on the growth of solid Ehrlich ascites tumour under the influence of hydrocortisone.

THE influence of adrenal cortical hormone on the connective tissue has been observed by some investigators. It was reported that cortisone acetate depressed sulphate (Na235SO4) incorporation into chondroitin sulphate and carbon (acetate-1-14C) incorporation into chondroitin sulphate and hyaluronic acid of rat skin (Schiller and Dorfman, 1957), and that a short period of elevated plasma corticosterone-levels caused a decrease in hyaluronic acid and chondroitin sulphate and in diffusibility of intradermally injected colloidal particles in rat skin (Fediay and Clay, 1964). At the same time, the inhibitory effect of adrenal cortical hormones on the growth of tumours has recently been studied by many workers (Watson, 1958; Moore, Kondo and Oliver, 1960; Kodama, 1962). The present author demonstrated the age and sex differences in inhibitory effect of hydrocortisone acetate on the growth of solid Ehrlich ascites tumour in SM mic

Higher derivative corrections to black hole thermodynamics from supersymmetric matrix quantum mechanics

We perform a direct test of the gauge-gravity duality associated with the system of N D0-branes in type IIA superstring theory at finite temperature. Based on the fact that higher derivative corrections to the type IIA supergravity action start at the order of \alpha'^3, we derive the internal energy in expansion around infinite 't Hooft coupling up to the subleading term with one unknown coefficient. The power of the subleading term is shown to be nicely reproduced by the Monte Carlo data obtained nonperturbatively on the gauge theory side at finite but large effective (dimensionless) 't Hooft coupling constant. This suggests, in particular, that the open strings attached to the D0-branes provide the microscopic origin of the black hole thermodynamics of the dual geometry including \alpha' corrections. The coefficient of the subleading term extracted from the fit to the Monte Carlo data provides a prediction for the gravity side, which can be checked once the complete form of the O(\alpha'^3) corrections to the supergravity action is obtained.Comment: REVTeX4, 4 pages, 2 figures. Ver.2:intuitive derivation of the subleading term adde