Astral microtubules are rapidly elongated during anaphase and telophase in sea urchin eggs. The number of microtubules extending to the cell surface was calculated with a computer. For the calculations, microtubules were assumed to radiate from the astral center uniformly over angles. Although microtubules from two asters freely overlapped around the equator, the number per the unit area, i.e. the surface density, was larger in the polar region than in the equatorial region. The ratio of the theoretically calculated numbers in (...) the two regions was close to the ratio obtained from the ultrastructural observations by Asnes and Schroeder in 1979. When counted in the longitudinal section including two astral centers, the microtubule number was a little larger in the equatorial region than in the polar region. However, the numbers do not represent the surface density because the two-dimensional section contains only a small portion of all the microtubules spreading in the three-dimensional space. The fluorescence image for tubulin, in most cases, provides the microtubule distribution in the longitudinal section. Therefore, from such an image, we cannot judge whether the surface density of astral microtubules is larger at the pole or at the equator. (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)

Experimental studies have developed, conducted, and evaluated classroom interventions for foreign language anxiety reduction. However, various characteristics of those classroom interventions make it difficult to synthesize the findings and apply them to practice. We conducted what is, to the best of our knowledge, the first systematic review on educational interventions for FLA. Six criteria were established for inclusion of studies. Using English keywords, we identified 854 potentially eligible studies through ProQuest and Scopus, 40 of which were finally included. All included (...) studies were published from 2007 to 2020. The studies differed in type of intervention, duration of intervention, and scale to measure FLA. Our systematic review resulted in seven features of classroom interventions, categorized as student–student interactions, student-teacher interactions, self-management, and mood boosters; we also categorized interventions as either individual or interactional. (shrink)

Using anthropological theory, this paper examines human–android interactions (HAI) as an emerging aspect of android science. These interactions are described in terms of adaptive learning (which is largely subconscious). This article is based on the observations reported and supplementary data from two studies that took place in Japan with a teleoperated android robot called Telenoid in the socialization of school children and older adults. We argue that interacting with androids brings about a special context, an interval, and a space/time for (...) reflection and imagination that was not there before. During the interaction something happens. There is adaptive learning and as a result, both children and older adults accepted Telenoid, and the children and older adults accepted each other. Using frames of play and ritual, we make sense and ‘capture’ moments of adaptive learning, and the feedback that elicits a social response from all study participants that results in self-efficacy and socialization. While “ritual” refers to the application of what has been learned and “play” means that there are no obvious consequences of what has been learned. This analysis illuminates new understanding about the uncanny valley, cultural robotics and the therapeutic potential of HAI. This has implications for the acceptance of androids in ‘socialized roles’ and gives us insight into the subconscious adaptive learning processes that must take place within humans to accept androids into our society. This approach aims to provides a clearer conceptual basis and vocabulary for further research of android and humanoid development. (shrink)

In this paper, we investigate the logical strength of completeness theorems for intuitionistic logic along the program of reverse mathematics. Among others we show that is equivalent over to the strong completeness theorem for intuitionistic logic: any countable theory of intuitionistic predicate logic can be characterized by a single Kripke model.

構造主義からアクターネットワークセオリーまで、哲学と人類学という二つの知的実践は交錯してきた。その現代的な意義を考える。 ドゥルーズ=ガタリ、メルロ=ポンティ、サルトル、モース、デュルケム、ヴィヴェイロス・デ・カストロ、デスコラ、ストラザーン――いずれも「自然」をめぐり、レヴィ=ストロースの神話論理の再解釈や「構造」の捉 えなおしとして進行してきた哲学と人類学について、思考様式の違いや歴史的な影響関係、主題の反復を浮き彫りにする。.

Currently in Japan, discontinuing an invasive mechanical ventilator (IMV) is illegal; therefore IMV-related decision making is a crucial issue. This study examined IMV decision-making factors and psychological conflict in 50 patients with amyotrophic lateral sclerosis. The Herth Hope Index was used for the assessment of pre- and post-IMV conflict. Interviews identified some decision-making factors: patient’s decision, patient’s and family’s mutual decision, family’s decision, and emergency-induced without patient’s or family’s consent. Participants who experienced no IMV-related regret received sufficient prior IMV education (...) from physicians and nurses, and time for reflection and family consultation. Their hope was similar to their pre-onset levels. Patients who received no prior IMV education accepted treatment as a natural progression. Their hope levels were lower than pre-onset. Those who received only a brief prior IMV explanation rejected the ventilator, experiencing regret if they were given an emergency IMV. Their hope levels were among the lowest. However, some of these patients managed to overcome their regret through being helped by nurses. Sufficient physician explanation and nursing advocacy for autonomous patient decision making are critical for improving hope in this patient group. (shrink)

In this paper, we investigate the logical strength of two types of fixed point theorems in the context of reverse mathematics. One is concerned with extensions of the Banach contraction principle. Among theorems in this type, we mainly show that the Caristi fixed point theorem is equivalent to math formula over math formula. The other is dedicated to topological fixed point theorems such as the Brouwer fixed point theorem. We introduce some variants of the Fan-Browder fixed point theorem and the (...) Kakutani fixed point theorem, which we call math formula and math formula, respectively. Then we show that math formula is equivalent to math formula and math formula is equivalent to math formula, over math formula. In addition, we also study the application of the Fan-Browder fixed point theorem to game systems. (shrink)