Kyoto College of Economics

Abstract Hypothalamic agouti-related peptide (AgRP) neurons that drive hunger-related behaviors are activated during energy deficit, encode negative valence but can be inhibited even by perception of food without digestion. Here, we show that in head-fixed mice, discrete motor actions such as spontaneous walking and conditioned licking rapidly suppress AgRP neuron activity. This suppression persisted throughout movement and terminated upon cessation, which was independent of food perception or conditioned cues. The degree of suppression was positively correlated with movement vigor. While optogenetic enhancement of AgRP neuron suppression did not initiate movement, it promoted reinforcement of concurrent walking behavior. These findings unmask that spontaneous, low intensity physical activity can reduce AgRP neuron activity reinforcing concurrent movement/exercise with implications for systemic health benefits.

Research and development (R&D) has been associated with the accomplishment of business results through capital investment. In recent years, the efficiency of R&D investment by US firms has declined; however, there is a lack of empirical evidence. Therefore, this study empirically analyses the relationship between R&D, capital investments, and the US firms' profitability. A regression analysis was conducted using data from US stock market-listed firms between fiscal years (FY) 2010 to 2021. The results indicate a significantly negative R&D ratio coefficient for all years. Additionally, the capital investment ratio coefficient was significantly positive in FY2019 and FY2021. However, for FY2011 it was positive but insignificant. The coefficients were significantly negative for all other years. The results indicate decreased efficiency of R&D investments by US firms, indicating opportunities to enhance their profitability. Moreover, the findings contribute to the existing literature and will assist practitioners make more informed management-related decisions.

This study investigates how people in Japan perceived the severity of and probability of infection from coronavirus disease 2019 (COVID-19), and how their willingness to purchase a hypothetical vaccine depends on these perceptions and their risk attitudes. We conducted a large-scale panel survey three times between 13 March to 13 April 2020 in Japan. By analyzing the data, we found that the perception of COVID-19 became more serious. The estimation of the fixed effect model reveals that a person becomes more willing to pay for a vaccine as the person evaluates COVID-19 as a more severe disease, considers a higher probability of infection, and becomes more risk averse. Since the sensitivity of willingness to pay for the vaccine on risk aversion increased during the period, the change in risk attitude contributed to an increase in willingness through the sensitivity channel, while it decreased through the magnitude channel.

This paper investigates a new voting rule wherein some people are given extra votes to serve as proxies for future generations. We predict that this voting scheme affects the voting behavior of those who do not receive an extra vote (i.e., single-ballot voters) because they are less likely to become a pivot, while proxy voters are expected to behave in support of the future generation. To test this prediction, we compare three scenarios wherein single-ballot voters would cast a vote: (a) one-voter-one-vote scenario wherein all voters cast only a single ballot; (b) a standard proxy-voting scenario wherein other voters cast two ballots, and the second vote is to cast for the benefit of a future generation; and (c) a non-proxy-voting scenario wherein other voters cast two ballots with no explanation for the second vote. The result shows that single-ballot voters are less inclined to vote for the future-oriented option in (c) than in (a). This indicates the potential drawback of the new voting scheme. However, there is no difference in the single-ballot voters’ decision between (a) and (b), indicating that the explanation of the second ballot as the proxy is important for reducing the intergenerational inequality through this voting reform.

We compared the safety and efficacy in mice with peritoneal carcinomatosis of two etoposide formulations: an aqueous solution (Etp-sol) and particles suspended in oil (the addition products of iodine and the ethyl esters of the fatty acids obtained from poppy-seed oil (Lipiodol) or sesame oil; Etp-oil). We also investigated tissue distribution of etoposide in rats treated with Etp-oil and Etp-sol. Etoposide was injected intraperitoneally at concentrations ranging from 52 to 392 mg/kg (increasing geometrically by a factor of 1.4). The 50% lethal dose (LD50), determined over a 2-week period of observation, was 135 mg/kg for Etp-oil and 108 mg/kg for Etp-sol. Autopsy findings included macroscopic intestinal bleeding, necrosis of the intestinal mucosa, and pulmonary congestion in mice from both treatment groups. In the efficacy trials. 10(6) P388 leukemia cells were transplanted into CDF1 male mice, and Etp-oil and Etp-sol were injected at doses of 20 mg/kg and 80 mg/kg. In the groups receiving the 20 mg/kg dose, 11 of 19 mice in the Etp-oil group survived to day 60 compared with 3 of 20 mice in the Etp-sol group. Toxicity-related deaths occurred in 1 of 20 mice treated with 80 mg/kg Etp-oil and in 8 of 20 mice treated with 80 mg/kg Etp-sol. No cancer-related deaths were associated with the 80 mg/kg dose in either treatment group. Our findings showed that the Etp-oil was associated with a lower toxicity and a higher efficacy than the Etp-sol. To evaluate tissue distribution, rats were injected intraperitoneally with 5 mg/kg body weight of Etp-sol or Etp-oil. The tissue distribution of etoposide was subsequently analyzed by high performance liquid chromatography. Compared with Etp-sol, Etp-oil delivered significantly greater amounts of etoposide and for a longer period to the omentum, taken as representative of the intraperitoneal tissue, and the etoposide concentration in blood plasma was increased more slowly and decreased more gradually.

The possible role of local motility in the pathogenesis of duodenal ulcers was investigated in rats using cysteamine. Duodenal motor activity was measured as intraluminal pressure recordings by means of a balloon positioned in the proximal duodenum. Subcutaneous administration of cysteamine (100 mg/kg) produced two linear bandlike lesions in the proximal duodenum within 6 hr. This dose of cysteamine significantly increased gastric acid secretion in acute fistula rats, and decreased duodenal HCO3- secretion caused by acid. During this period, this agent inhibited gastric motility but did produce markedly enhanced contractions in the duodenum. The changes in duodenal motility appeared within 5-10 min and were dose-dependent for cysteamine (10-100 mg/kg). Pretreatment with subcutaneously administered atropine (10 mg/kg), 16,16-dmPGE2 (30 micrograms/kg) or dopamine (10 or 30 mg/kg) significantly reduced the development of duodenal lesions caused by cysteamine, the inhibition being 86.8%, 49.7%, 54.5% or 67.8%, respectively. In the presence of cysteamine, dopamine had minimal effect on both acid and HCO3- secretion, while atropine or 16,16-dmPGE2 markedly inhibited acid secretion or increased HCO3- secretion, respectively. The enhanced duodenal motility induced by cysteamine was blocked partially by atropine and only slightly by 16,16-dmPGE2. Dopamine showed a dose-dependent inhibition on the duodenal hypermotility following cysteamine, and at 30 mg/kg almost completely abolished the development of contractions. These results suggest that abnormal hypermotility in the duodenum may be partly involved in the pathogenesis of cysteamine-induced duodenal ulcers.

Semiconductor devices for light amplification in that 1-μm wavelength region have already been proposed,1,2 such as the direct and vertical integration devices, e.g., a double heterojunction light-emitting diode integrated onto the collector portion of a heterojunction phototransistor, as shown in Fig. 1, or vice versa. It was experimentally observed that the input light intensity is amplified and the maximum gain is ~10.

Effects of 16-dimethyl prostaglandin E2 (16-dmPGE2) and necrotizing agents on gastric motility and gastric mucosa were studied in conscious rats. Gastric motility was determined using a miniature balloon positioned in the glandular part of the stomach, which was connected to a pressure transducer and polygraph. Necrotizing agents, such as absolute ethanol, 0.6 N HCl, 0.2 N NaOH, or 4 M NaCl, were instilled into the stomach through a small fistula prepared in the forestomach. One milliliter of these agents produced streak lesions in the glandular part of the stomach within 1 hr, which were preceded by violent gastric contraction in every case. An intragastric administration of 16-dmPGE2 (0.3-3 micrograms/kg) by itself increased a tonus of the gastric wall but dose-dependently lessened the number and the amplitude of contractions. In those rats treated with 16-dmPGE2 (3 micrograms/kg), necrotizing agents failed to enhance the motility or to induce streak lesions. Pretreatment with 1 M NaCl as a mild irritant also inhibited gastric motility and lesion formation, but those actions were significantly antagonized by indomethacin (5 mg/kg). These results indicate that necrotizing agents induce a violent gastric contraction, followed by development of lesions in the stomach, and that the inhibition of gastric hypercontraction may be involved in a cytoprotective action of a prostaglandin against those induced gastric lesions in rats.