IPO企業の経営陣は投資家に何を教えたか？ : 中国市場のIPOオンラインロードショーからの証拠

中国証券市場において，取引者の多数を占める小口投資家は新規上場企業のオフラインロードショーに参加することができない。そのため，オンラインロードショーは彼らが企業の経営を知るための重要な方法である。本研究は2010年から2018年までに深圳証券取引所の中小企業ボードに新規上場する企業を研究対象とし，企業が開催したオンラインロードショーにおける投資家の質問と経営陣の回答の問答関連度を計量して，さらに，問答関連度と新規上場企業の初期パフォーマンスの関係を検証した。検証結果によると，オンラインロードショーでの質問と回答の関連度が高ければ高いほど，初期収益率と流動性が高くなる。また，長期的には，問答関連度の高い企業は株価が安定しているものの，問答関連度の低い企業は株価が低下しつつある傾向があるということが追加検証で分かる。オンラインロードショーは，投資家と新規上場企業間の情報非対称性を，ある程度緩和でき，企業価値を評価するには大切な役割を果たしている。Retail investors, who are the majority traders in the Chinese stock market, cannot participate in off-line roadshows of IPO firms. Online roadshows are an important channel for them to learn about the situation of IPO firms. This study takes the IPO firms which are new-listed in Shenzhen Stock Exchange from 2010 to 2018 as the research subject, investigates the relationship between question-answers relevance in online roadshows and the first-day performance of IPO firms. According to the results, a high-level of question-answers relevance leads to a high first-day return and high liquidity. Furthermore, the additional analysis shows that the IPO firms with a high-level of question-answers relevance show stable long-term stock returns, on the contrary, the IPO firms with a low-level of question-answers relevance show the trends to decrease. Online roadshows could mitigate the information asymmetry between the investors and IPO firms, and play an important role in assessing firm values

新型コロナ禍における国際教育への挑戦

Due to the COVID-19, many countries including Japan have reinforced regulations at the borders. As many international students could not enter Japan due to the COVID-19 pandemic, some universities offered online education services as an alternate. On the other hand, since April 2020, many of international student livening in Japan have not been able to go back to their countries

Investigation of small-fraction molecular impurities in high-pressure helium plasmas using optical plasma diagnostic methods

In high-pressure plasmas using gases diluted via a rare gas, small-fraction impurities in the discharge space significantly impact the basic plasma parameters and excited-species generation processes. This study investigated the behaviors of molecular impurities in a dielectric barrier discharge (DBD) generated in a flow of high-purity He gas using optical plasma diagnostic methods. The optical emission spectra obtained under various discharge conditions (pressure, flow rate, and voltage frequency) indicated that the major impurity species in the He DBD was the H₂O molecule, and the DBD decomposed the H₂O before reaching the measurement spot. To quantitatively analyze the H₂O fraction, time-resolved laser absorption spectroscopy was performed to measure the exponential decay time of He metastable (Hem) atoms in the He-DBD. The H₂O fraction in the He gas flow was derived from the dependence of Hem lifetime decay on the voltage frequency. In addition, a model was proposed to estimate the H₂O fraction under various He pressure and flow rate conditions from reference data. The procedures to perform optical plasma diagnostics and evaluate the fraction and behavior of H₂O impurities are expected to facilitate a better understanding and control of high-pressure plasmas

Identification of plb1 mutation that extends longevity via activating Sty1 MAPK in Schizosaccharomyces pombe

To understand the lifespan of higher organisms, including humans, it is important to understand lifespan at the cellular level as a prerequisite. So, fission yeast is a good model organism for the study of lifespan. To identify the novel factors involved in longevity, we are conducting a large-scale screening of long-lived mutant strains that extend chronological lifespan (cell survival in the stationary phase) using fission yeast. One of the newly acquired long-lived mutant strains (No.98 mutant) was selected for analysis and found that the long-lived phenotype was due to a missense mutation (92Phe → Ile) in the plb1^+ gene. plb1^+ gene in fission yeast is a nonessential gene encoding a homolog of phospholipase B, but its functions under normal growth conditions, as well as phospholipase B activity, remain unresolved. Our analysis of the No.98 mutant revealed that the plb1 mutation reduces the integrity of the cellular membrane and cell wall and activates Sty1 via phosphorylation