Genetic and morphological differences between Sebastes vulpes and S. zonatus (Teleostei: Scorpaeniformes: Scorpaenidae)

The taxonomic status of Sebastes vulpes and S. zonatus were clarified by comprehensive genetic (amplif ied fragment length polymorphisms [AFLP] and mitochondrial DNA [mtDNA] variation) and morphological analyses on a total of 65 specimens collected from a single locality. A principal coordinate analysis based on 364 AFLP loci separated the specimens completely into two genetically distinct groups that corresponded to S. vulpes and S. zonatus according to body coloration and that indicated that they are reproductively isolated species. Significant morphological differences were also evident between the two groups; 1) separation by principal component analysis based on 31 measurements, and 2)separation according to differences in counts of gill rakers and dorsal-fin spines without basal scales, and in the frequencies of specimens with small scales on the lower jaw. Restriction of gene flow between the two groups was also indicated by the pairwise ΦST values estimated from variations in partial sequences from the mtDNA control region, although the minimum spanning network did not result in separation into distinct clades. The latter was likely due to incomplete lineage sorting between S. vulpes and S. zonatus owing to their recent speciation

Strategic Complexity in Repeated Extensive Games

This paper studies a two-player machine (finite automaton) game in which an extensive game with perfect information is infinitely repeated. We introduce a new measure of strategic complexity named "multiple complexity", which considers the responsiveness of a strategy to information as well as the number of states of machines. In contrast to Piccione and Rubinstein (1993), we prove that a machine game may include non-trivial Nash equilibria. In the sequential-move prisoners' dilemma, cooperation can be sustained in an equilibrium of the machine game.

Revenue-capped efficient auctions

We study an auction that maximizes the expected social surplus under an upperbound constraint on the seller's expected revenue, which we call a revenue cap. Such a constrained-efficient auction may arise, for example, when: (i) the auction designer is "pro-buyer", that is, he maximizes the weighted sum of the buyers' and seller's auction payoffs, where the weight for the buyers is greater than that for the seller; (ii) the auction designer maximizes the (unweighted) total surplus in a multi-unit auction in which the number of units the seller owns is private information; or (iii) multiple sellers compete to attract buyers before the auction. We characterize the mechanisms for constrained-efficient auctions and identify their important properties. First, the seller sets no reserve price and sells the good for sure. Second, with a nontrivial revenue cap, "bunching" is necessary. Finally, with a sufficiently severe revenue cap, the constrained-efficient auction has a bid cap, so that bunching occurs at least "at the top," that is, "no distortion at the top" fails

Revenue-capped efficient auctions

We study an auction that maximizes the expected social surplus under an upperbound constraint on the seller's expected revenue, which we call a revenue cap. Such a constrained-efficient auction may arise, for example, when: (i) the auction designer is "pro-buyer", that is, he maximizes the weighted sum of the buyers' and seller's auction payoffs, where the weight for the buyers is greater than that for the seller; (ii) the auction designer maximizes the (unweighted) total surplus in a multi-unit auction in which the number of units the seller owns is private information; or (iii) multiple sellers compete to attract buyers before the auction. We characterize the mechanisms for constrained-efficient auctions and identify their important properties. First, the seller sets no reserve price and sells the good for sure. Second, with a nontrivial revenue cap, "bunching" is necessary. Finally, with a sufficiently severe revenue cap, the constrained-efficient auction has a bid cap, so that bunching occurs at least "at the top," that is, "no distortion at the top" fails

List-based decision problems

When encountering a set of alternatives displayed in the form of a list, the decision maker usually determines a particular alternative, after which she stops checking the remaining ones, and chooses an alternative from those observed so far. We present a framework in which both decision problems are explicitly modeled, and axiomatically characterize a stop-and-choose rule which unifies position-biased successive choice and satisficing choice

Field Effect of Alcohol, Cigarette Smoking, and Their Cessation on the Development of Multiple Dysplastic Lesions and Squamous Cell Carcinoma: A Long-term Multicenter Cohort Study

[Background and Aims] Multiple developments of squamous dysplasia and squamous cell carcinoma (SCC) in the upper aerodigestive tract have been explained by field cancerization phenomenon and were associated with alcohol and cigarette use. Second primary SCC development after curative treatment impairs patients’ quality of life and survival; however, how these consumption and cessation affect field cancerization is still unknown. [Methods] This is a multicenter cohort study including 331 patients with superficial esophageal SCC (ESCC) treated endoscopically and pooled data from 1022 healthy subjects for comparison. Physiological condition in the background esophageal mucosa was classified into 3 groups based on the number of Lugol-voiding lesions (LVLs) per endoscopic view: grade A, 0; grade B, 1–9; or grade C, ≥10 LVLs. Lifestyle surveys were conducted using a self-administered questionnaire. Patients were counseled on the need for alcohol and smoking cessation by physicians and were endoscopically surveyed every 6 months. [Results] LVL grades were positively associated with alcohol drinking intensity, flushing reactions, smoking, and high-temperature food and were negatively associated with eating green and yellow vegetables and fruit. Second primary ESCC and head/neck SCC were significantly more prevalent in the grade C LVL (cumulative 5-y incidences 47.1%, 95% confidence interval [CI] = 38.0–57.2 and 13.3%, 95% CI = 8.1–21.5, respectively). Alcohol and smoking cessation significantly reduced the development of second primary ESCC (adjusted hazard ratios 0.47, 95% = CI 0.26–0.85 and 0.49, 95% CI = 0.26–0.91, respectively). [Conclusion] Alcohol drinking, smoking, flushing reaction, and high-temperature food were closely associated with field cancerization, and cessation of alcohol and smoking significantly reduced the risk of development of second primary cancer. UMIN Clinical Trials Registry ID:UMIN000001676

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

キツネメバル複合種群(メバル科)の進化系統分類学的研究

京都大学0048新制・課程博士博士(農学)甲第17831号農博第2016号新制||農||1016(附属図書館)学位論文||H25||N4788(農学部図書室)30646京都大学大学院農学研究科応用生物科学専攻(主査)教授 中坊 徹次, 准教授 田川 正朋, 准教授 豊原 治彦学位規則第4条第1項該当Doctor of Agricultural ScienceKyoto UniversityDGA