Japanese Banks' Monitoring Activities and the Performance of Borrower Firms: 1981-1996

Using micro data of Japanese banks and borrower firms, we construct an index measure that quantitatively describes the monitoring activities of Japanese banks. We examine the effects of bank monitoring on the profitability of borrower firms. We find significant positive effects in the periods 1986-1991 and 1992-1996, although there is no significant effect in the 1981-1985 period . We also examine how banks' monitoring affects borrowers. The results show that the positive effects of banks' monitoring on borrowers' profitability are mostly caused by screening effects, not performance-improving effects.

Stock Price Forecast and Business Fluctuation

これまでの理論分析では予測形成が経済政策の有効性に与える影響が多く分析されてきたが，実際の人々の予測形成の在り方に関する分析が少ない．本研究は，毎年年初の『日本経済新聞』に掲載される経営者の株価予測を対象として予測形成の特徴及びそれが実体経済に及ぼす影響を検証する．われわれの検証結果では，経営者による株価の高値安値の発生時期に関する予測は予測対象の発生時期と何ら相関を持っていない．また高値安値水準に関する予測はその実現値よりも関連指標のうち予測時点の株価に最も近い．その意味において株価高値安値水準に関する予測は適合的性質を持っている．株価予測による実体経済への影響については，高値予測は法人企業部門の設備投資に大きなインパクトを持つことが観察される．このことは人々の予測形成自体は実体経済に影響を及ぼす可能性を示唆している．バブル崩壊後，長く景気低迷を続いている日本にとって不必要な悲観論をただすことも重要な景気対策の一部といえよう．In this paper, we focus on the business leaders’ forecast of stock prices, published by Nihon Keizai Shibun, and study their characteristics and their impact to the real economy.We find that the forecasts of the timing of the highest or the lowest stock price does not correlate with the timing of realizations, but the forecasts on the price level do correlate with the nearest historical value. We also find that some of the forecast measures do have some real impacts to the economy. These findings suggest that the pessimistic view of the future after the burst of bubble may itself formed an important factor of the economic recession.特集　新しい金融経済

Richard F. Kahn The Making of Keynes\u27General Theory Cambridge University Press（1984）

特集　ケインズとその時代を読

"Banks' Monitoring and Profitability of Borrowing Firms"(in Japanese)

We constructed measures representing the magnitude of Japanese banks' monitoring activities and tested two competing hypotheses about nature of banks' monitoring, (1) the monitoring improved profitability of borrowing firms and (2) it simply "screened" out unprofitable firms, by using the data of all Japanese corporations listed in the Tokyo Stock Exchange between 1986 and 1997. The result was inconsistent with the profitability-improving hypothesis of banks' active involvement in borrowing firms, and strongly suggested the banks' passive role as a screening device.

An Updated Search of Steady TeV γ−\gamma-Ray Point Sources in Northern Hemisphere Using the Tibet Air Shower Array

Using the data taken from Tibet II High Density (HD) Array (1997 February-1999 September) and Tibet-III array (1999 November-2005 November), our previous northern sky survey for TeV $\gamma-$ray point sources has now been updated by a factor of 2.8 improved statistics. From $0.0^{\circ}$ to $60.0^{\circ}$ in declination (Dec) range, no new TeV $\gamma-$ray point sources with sufficiently high significance were identified while the well-known Crab Nebula and Mrk421 remain to be the brightest TeV $\gamma-$ray sources within the field of view of the Tibet air shower array. Based on the currently available data and at the 90% confidence level (C.L.), the flux upper limits for different power law index assumption are re-derived, which are approximately improved by 1.7 times as compared with our previous reported limits.Comment: This paper has been accepted by hepn

Broadening of Neutralization Activity to Directly Block a Dominant Antibody-Driven SARS-Coronavirus Evolution Pathway

Phylogenetic analyses have provided strong evidence that amino acid changes in spike (S) protein of animal and human SARS coronaviruses (SARS-CoVs) during and between two zoonotic transfers (2002/03 and 2003/04) are the result of positive selection. While several studies support that some amino acid changes between animal and human viruses are the result of inter-species adaptation, the role of neutralizing antibodies (nAbs) in driving SARS-CoV evolution, particularly during intra-species transmission, is unknown. A detailed examination of SARS-CoV infected animal and human convalescent sera could provide evidence of nAb pressure which, if found, may lead to strategies to effectively block virus evolution pathways by broadening the activity of nAbs. Here we show, by focusing on a dominant neutralization epitope, that contemporaneous- and cross-strain nAb responses against SARS-CoV spike protein exist during natural infection. In vitro immune pressure on this epitope using 2002/03 strain-specific nAb 80R recapitulated a dominant escape mutation that was present in all 2003/04 animal and human viruses. Strategies to block this nAb escape/naturally occurring evolution pathway by generating broad nAbs (BnAbs) with activity against 80R escape mutants and both 2002/03 and 2003/04 strains were explored. Structure-based amino acid changes in an activation-induced cytidine deaminase (AID) “hot spot” in a light chain CDR (complementarity determining region) alone, introduced through shuffling of naturally occurring non-immune human VL chain repertoire or by targeted mutagenesis, were successful in generating these BnAbs. These results demonstrate that nAb-mediated immune pressure is likely a driving force for positive selection during intra-species transmission of SARS-CoV. Somatic hypermutation (SHM) of a single VL CDR can markedly broaden the activity of a strain-specific nAb. The strategies investigated in this study, in particular the use of structural information in combination of chain-shuffling as well as hot-spot CDR mutagenesis, can be exploited to broaden neutralization activity, to improve anti-viral nAb therapies, and directly manipulate virus evolution

Synthesis and White-Light Emission of ZnO/HfO2: Eu Nanocables

ZnO/HfO2:Eu nanocables were prepared by radio frequency sputtering with electrospun ZnO nanofibers as cores. The well-crystallized ZnO/HfO2:Eu nanocables showed a uniform intact core–shell structure, which consisted of a hexagonal ZnO core and a monoclinic HfO2 shell. The photoluminescence properties of the samples were characterized. A white-light band emission consisted of blue, green, and red emissions was observed in the nanocables. The blue and green emissions can be attributed to the zinc vacancy and oxygen vacancy defects in ZnO/HfO2:Eu nanocables, and the yellow–red emissions are derived from the inner 4f-shell transitions of corresponding Eu3+ ions in HfO2:Eu shells. Enhanced white-light emission was observed in the nanocables. The enhancement of the emission is ascribed to the structural changes after coaxial synthesis