Daily rhythms are a ubiquitous feature of living systems. Generally, these rhythms are not just passive consequences of cyclic fluctuations in the environment, but instead originate within the organism. In mammals, including humans, the master pacemaker controlling 24‐hour rhythms is localized in the suprachiasmatic nuclei of the hypothalamus. This circadian clock is responsible for the temporal organization of a wide variety of functions, ranging from sleep and food intake, to physiological measures such as body temperature, heart rate and hormone release. (...) The retinal circadian clock was the first extra‐SCN circadian oscillator to be discovered in mammals and several studies have now demonstrated that many of the physiological, cellular and molecular rhythms that are present within the retina are under the control of a retinal circadian clock, or more likely a network of hierarchically organized circadian clocks that are present within this tissue. BioEssays 30:624–633, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

In this paper, we show within ${\mathsf{RCA}_0}$ that both the Jordan curve theorem and the Schönflies theorem are equivalent to weak König’s lemma. Within ${\mathsf {WKL}_0}$ , we prove the Jordan curve theorem using an argument of non-standard analysis based on the fact that every countable non-standard model of ${\mathsf {WKL}_0}$ has a proper initial part that is isomorphic to itself (Tanaka in Math Logic Q 43:396–400, 1997).

Genome maintenance requires various nucleoid-associated factors in prokaryotes. Among them, the SMC protein has been thought to play a static role in the organization and segregation of the chromosome during cell division. However, recent studies have shown that the bacterial SMC is required to align left and right arms of the emerging chromosome and that the protein dynamically travels from origin to Ter region. A rod form of the SMC complex mediates DNA bridging and has been recognized as a machinery (...) responsible for DNA loop extrusion, like eukaryotic condensin or cohesin complexes, which act as chromosome organizers. Attention is now turning to how the prototype of the complex is loaded on the entry site and translocated on chromosomal DNA, explaining its overall conformational changes at atomic levels. Here, we review and highlight recent findings concerning the prokaryotic SMC complex and discuss possible mechanisms from the viewpoint of protein architecture. Recent studies show dynamic movements of the prokaryotic SMC protein complex: initial loading, translocation on DNA for bacterial chromosome organization. The recent structural models of the protein also provide a new vision for the structure-function relationship. (shrink)

This monograph is the first to analyze Julius Caesar Scaliger's Exotericae Exercitationes(1557). In order to make this late-Renaissance work accessible to modern readers, Kuni Sakamoto conducted a detailed textual analysis and revealed the basic tenets of Scaliger's philosophy.

Recently, several funding agencies have introduced the distribution of funds by a lottery system; however, its effects on the productivity of the research community are unclear. Simulation studies in philosophy of science have argued that a combination of peer review and lottery is an optimal method. However, these models overlook several important aspects of research activities, such as baseline funding through block grants. In this study, I constructed a general theoretical model that incorporates these aspects and argue that the conventional (...) combination of peer review and baseline funding outperforms the combination of peer review and lottery in many situations. (shrink)

Pierre Gassendi is widely known as a reviver of Epicurean atomism. But he was also regarded as an accomplished astronomer by his contemporaries. Along with the life-long observational pursuits, Gassendi developed his theories of the causes underlying celestial motions. In elaborating them, he absorbed seveal ideas coming from the astronomy of Johannes Kepler. Moreover, Gassendi went further to incorporate some theological principles from the Keplerian cosmology, especially the idea that God is a Geometer. The present paper thus explores Kepler's influence (...) on the philosophy of Gassendi in both astronomical and theological spheres. (shrink)

清朝末から中華人民共和国建国までの世界的激動期、中国の知識人は儒教的世界観の更新に立ち会い、西洋の知と格闘した。社会進化論や立憲思想の衝撃はナショナリズムと革命思想に展開し、雑誌メディアには生命論から 民族論まで様々な論争と漫画表現が花開く。貴重な資料と最新の研究から読み解く労作。.

正しいから証明できるのか、証明できるから正しいのか。数学にとって証明とは何か、正しさとは何なのかは数学基礎論の根本的な問題である。様相論理を軸とした、証明と真理に関わる数学基礎論の古典的な結果から最先 端の議論までを解説した。.

One of the problems we face in many-valued logic is the difficulty of capturing the intuitive meaning of the connectives introduced through truth tables. At the same time, however, some logics have nice ways to capture the intended meaning of connectives easily, such as four-valued logic studied by Belnap and Dunn. Inspired by Dunn’s discovery, we first describe a mechanical procedure, in expansions of Belnap-Dunn logic, to obtain truth conditions in terms of the behavior of the Truth and the False, (...) which gives us intuitive readings of connectives, out of truth tables. Then, we revisit the notion of functional completeness, which is one of the key notions in many-valued logic, in view of Dunn’s idea. More concretely, we introduce a generalized notion of functional completeness which naturally arises in the spirit of Dunn’s idea, and prove some fundamental results corresponding to the classical results proved by Post and Słupecki. (shrink)

The purpose of this paper is to argue that the hybrid formalism fits naturally in the context of David Lewis’s counterfactual logic and that its introduction into this framework is desirable. This hybridization enables us to regard the inference “The pig is Mary; Mary is pregnant; therefore the pig is pregnant” as a process of updating local information (which depends on the given situation) by using global information (independent of the situation). Our hybridization also has the following technical advantages: (i) (...) it preserves the completeness and decidability of Lewis’s logic; (ii) it allows us to characterize the Limit Assumption as a proof-rule with some side-conditions; and (iii) it enables us to establish a general Kripke completeness result by using the proof-rule corresponding to the Limit Assumption. Keywords Counterfactual logic - David Lewis - Contextually definite description - Hybrid logic - Arthur Prior - The limit assumption - Strong completeness - Decidability - Bisimulation - Pure completeness. (shrink)

In this paper, we discuss uniform versions of some axioms of second order arithmetic in the context of higher order arithmetic. We prove that uniform versions of weak weak König's lemma WWKL and Σ01 separation are equivalent to over a suitable base theory of higher order arithmetic, where is the assertion that there exists Φ2 such that Φf1 = 0 if and only if ∃x0 for all f. We also prove that uniform versions of some well-known theorems are equivalent to (...) or the axiom of the existence of the Suslin operator. (shrink)

This paper studies a combined system of intuitionistic and classical propositional logic from proof-theoretic viewpoints. Based on the semantic treatment of Humberstone (J Philos Log 8:171–196, 1979) and del Cerro and Herzig (Frontiers of combining systems: FroCoS, Springer, 1996), a sequent calculus $$\textsf{G}(\textbf{C}+\textbf{J})$$ is proposed. An approximate idea of obtaining $$\textsf{G}(\textbf{C}+\textbf{J})$$ is adding rules for classical implication on top of the intuitionistic multi-succedent sequent calculus by Maehara (Nagoya Math J 7:45–64, 1954). However, in the semantic treatment, some formulas do not (...) satisfy heredity, which leads to the necessity of a restriction on the right rule for intuitionistic implication to keep the soundness of the calculus. The calculus $$\textsf{G}(\textbf{C}+\textbf{J})$$ enjoys cut elimination and Craig interpolation, whose detailed proofs are described in this paper. Cut elimination enables us to show the decidability of this combination both directly and syntactically. This paper also employs a canonical model argument to establish the strong completeness of Hilbert system $$\mathbf {C+J}$$ proposed by del Cerro and Herzig (Frontiers of combining systems: FroCoS, Springer, 1996). (shrink)

This paper deals with two main topics: One is a semantical investigation for a bimodal language with a modal operator \blacksquare associated with the intersection of the accessibility relation R and the inequality ≠. The other is a generalization of some of the former results to general extended languages with modal operators. First, for our language L\sb{\square\blacksquare}, we prove that Segerberg's theorem (equivalence between finite frame property and finite model property) fails and establish both van Benthem-style and Goldblatt-Thomason-style characterizations. We (...) extract the notion of \blacksquare-realizer (a generalization of bulldozing) as an essence from the proofs of our results. Second, we generalize the notion of \blacksquare-realizer and prove quite general versions of these semantical characterization results. The known and previously unknown characterization results for almost all of the languages extended with modal operators already proposed will be immediate corollaries. (shrink)

The discipline of nursing has long maintained that is has a unique contribution to make within the health care arena. This assertion of uniqueness lies in great part in the discipline's claim to a distinct body of knowledge. Nursing knowledge is characterized by diverse and multiple forms of knowing and underpins the work of all nurses, regardless of field of practice. Unfortunately, it has been challenging for the discipline to take full ownership of its epistemological diversity, largely due to factors (...) such as competing worldviews, and ideological and binary positioning. A philosophical middle ground stance is proposed as a way for the discipline to contemplate, discuss and develop nursing knowledge; a middle space that provides the freedom to consider competing worldviews while still allowing for the discipline to fully express itself in all of its epistemological diversity. In being able to enact its multiple forms of knowledge in a creative and open space that is open to different ideas and worldviews, not only can nursing take full ownership of its practice and its unique knowledge, it can also demonstrate how best to navigate an increasingly polarized world. In a world that is increasingly fixated on binary solutions and dualistic points of view, it is time for nursing to celebrate its epistemological diversity. (shrink)

劇的転換を求められている新たな生命倫理の案内書。従来、医療分野に集中しがちであった内容を生命科学全体とさらに関連する社会的緊急課題―環境・人口・難民・人種などにまで拡大、包括して最適任者が興趣ある解説 で応える。.

Societies with a higher level of income inequality tend to have lower levels of intergenerational income mobility. Known as the Great Gatsby Curve, this negative relationship in part derives from greater intergenerational economic heritance among the poor. Societies with higher rates of relative poverty will have a higher level of income inequality, but they will also tend to have lower intergenerational mobility due to the reduced capacity of low-income persons to become upwardly mobile. Reviewing relevant research in psychology, we describe (...) how poverty is associated with decreased psychological resources that compromise the competitiveness of low-income persons for superior attainment in the educational system and for greater productivity in the labor market. Economic deprivation in itself thus leads to a “vicious circle” of disadvantage that diminishes intergenerational mobility even without the existence of any culture of poverty or monopolistic institutions in the economy. (shrink)