Frequentist probability in Japanese school curricula

Many Japanese school mathematics teachers, policy-makers and researchers believe that probabilistic contents are difficult for most students to understand. In this study, I identify several reasons for the difficulty through an ecological analysis that is a part of a didactic analysis. This task is achieved through three research techniques: (a) constructing a reference epistemological model of probabilistic activities in terms of praxeology, (b) analysing probabilistic contents of Japanese school mathematics textbooks from the reference model and (c) identifying institutional conditions and constraints on the contents using the scale of levels of didactic codetermination. In current Japanese school mathematics, frequentist probability is hardly mentioned, whereas Laplacian probability comprises a large part of the curriculum of probability, although some generic conditions make the frequentist probability viable. This fact is related to the following three constraints: determinationism, theoricism and demathematisation of randomisers

確率概念の形成におけるミスコンセプションの研究

広島大学(Hiroshima University)博士(教育学)Doctor of Philosophy in Educationdoctora

Synthesis and Characterization of Hydrous Zirconia as an Ion-exchanger for Removal of Radioactive Iodine

In terms of nuclear waste management, the behavior of radionuclides with long half-lives, such as I-129, is of special concern especially for the final depository of nuclear waste. In addition, generally speaking, iodine is highly mobile and easily transferable to the natural environment. Furthermore, because iodine is an essential element for the synthesis of thyroid hormones, it accumulates in the human thyroid. Thus, radioactive iodine can also be the greatest potential danger of dose uptake for humans. Among many kinds of iodine species, it is rather challenging to separate iodate selectively from other anions and thus it is necessary to investigate new materials which can adsorb iodate efficiently for the removal of radioactive iodine. In this study, the iodate adsorption ability of hydrous zirconia has been investigated. Hydrous zirconia has been reported as an anion-exchanger, and because of its stability, this material is a promising candidate for selective iodate removal from radioactive waste solutions. White solid of hydrous zirconia was successfully synthesized with an amorphous structure. Its surface showed a character in between amphoteric and basic. The isotherm indicated that the material has a preference to adsorb iodate and the saturation value of adsorption was estimated to 1.8 mmol/g. The material showed lower uptakes as pH got higher. Among several competing anions tested, divalent sulphate ions suppressed the iodate adsorption to some extent due to higher affinity to the material surface. In a basic environment, boric acid also suppressed strongly the adsorption probably because of the formation of tetrahydroxyborate with hydroxide sites on the material surface. These suppressions of iodate adsorption became stronger as the concentration got higher. Post-heating at 400 °C resulted in the transformation of the material structure to tetragonal and a slight improvement of iodate adsorption rate. As the temperature of post-heating got higher, the structure became more monoclinic and showed the lower uptakes, which may be due to the loss of hydroxide sites. A column setup of the material with simulant of wastewater from Fukushima Daiichi Nuclear Power Plant has been operating and approximately 11,000 bed-volume of the solution has been gone through, but still, the column is yet to reach a 100% breakthrough. Based on the results presented in this study, it can be concluded that synthesized hydrous zirconia showed clear iodate preference and a possible high performance for the waste treatment from nuclear power plants

A Theory of Quantitative Easing Policy and Negative Interest Policy Based on the Japanese Experience

Using a two-period overlapping-generations model, I elucidate how quantitative easing policy and negative interest policy affect an economy based on the Japanese experience under the Abe cabinet. Quantitative easing policy forces a huge amount of money hoarding. Accordingly, the rate of return for money is required to rise. This implies that disinflation and/or deflation are accelerated in Japan, which is in line with reality. On the other hand, quantitative easing policy stimulates the aggregate demand, which brings about a mild recovery in business. The business upturn tightens the foreign market because of an increase in imports and causes the home currency to depreciate.Negative interest policy implies there is a tax levied on money hoarding. Hence, as longas the government expenditure is kept constant, money circulating in an economy decreases, thereby discouraging business. Such a downturn reduces aggregate income and imports. This induces excess supply of foreign exchange. Consequently, the exchange rate appreciates to equilibrate the market.These characteristics of the business cycle in conjunction with changes in the attitude of the monetary authority are entirely consistent with the current Japanese experience under Abenomics

Contact-Mediated Eyespot Color-Pattern Changes in the Peacock Pansy Butterfly: Contributions of Mechanical Force and Extracellular Matrix to Morphogenic Signal Propagation

Butterfly wing color patterns are developmentally determined by morphogenic signals from organizers in the early pupal stage. However, the precise mechanism of color-pattern determination remains elusive. Here, mechanical and surface disturbances were applied to the pupal hindwing of the peacock pansy butterfly Junonia almana (Linnaeus, 1758) to examine their effects on color-pattern determination. Using the forewing-lift method immediately after pupation, a small stainless ball was placed on the prospective major eyespot or background of the developing dorsal hindwing to cause a wing epithelial distortion, resulting in deformation of the major eyespot. When the exposed dorsal hindwing was covered with a piece of plastic film or placed on a surface of a glass slide, an adhesive tape, or a silicone-coated glassine paper, the major eyespot was effectively reduced in size without a direct contact with the covering materials. The latter two treatments additionally induced the size reduction of the minor eyespot and proximal displacement and broadening of parafocal elements through a direct contact, being reminiscent of the temperature-shock-type modifications. These results suggest the importance of mechanical force and physicochemical properties of planar epithelial contact surface (i.e., extracellular matrix) to propagate morphogenic signals for color-pattern determination in butterfly wings

Structural analysis of eyespots: dynamics of morphogenic signals that govern elemental positions in butterfly wings

<p>Abstract</p> <p>Background</p> <p>To explain eyespot colour-pattern determination in butterfly wings, the induction model has been discussed based on colour-pattern analyses of various butterfly eyespots. However, a detailed structural analysis of eyespots that can serve as a foundation for future studies is still lacking. In this study, fundamental structural rules related to butterfly eyespots are proposed, and the induction model is elaborated in terms of the possible dynamics of morphogenic signals involved in the development of eyespots and parafocal elements (PFEs) based on colour-pattern analysis of the nymphalid butterfly <it>Junonia almana</it>.</p> <p>Results</p> <p>In a well-developed eyespot, the inner black core ring is much wider than the outer black ring; this is termed the inside-wide rule. It appears that signals are wider near the focus of the eyespot and become narrower as they expand. Although fundamental signal dynamics are likely to be based on a reaction-diffusion mechanism, they were described well mathematically as a type of simple uniformly decelerated motion in which signals associated with the outer and inner black rings of eyespots and PFEs are released at different time points, durations, intervals, and initial velocities into a two-dimensional field of fundamentally uniform or graded resistance; this produces eyespots and PFEs that are diverse in size and structure. The inside-wide rule, eyespot distortion, structural differences between small and large eyespots, and structural changes in eyespots and PFEs in response to physiological treatments were explained well using mathematical simulations. Natural colour patterns and previous experimental findings that are not easily explained by the conventional gradient model were also explained reasonably well by the formal mathematical simulations performed in this study.</p> <p>Conclusions</p> <p>In a mode free from speculative molecular interactions, the present study clarifies fundamental structural rules related to butterfly eyespots, delineates a theoretical basis for the induction model, and proposes a mathematically simple mode of long-range signalling that may reflect developmental mechanisms associated with butterfly eyespots.</p

Understanding Low-Dose Exposure and Field Effects to Resolve the Field-Laboratory Paradox: Multifaceted Biological Effects from the Fukushima Nuclear Accident

Many reports about the biological effects of the Fukushima nuclear accident on various wild organisms have accumulated in recent years. Results from field-based laboratory experiments using the pale grass blue butterfly have clearly demonstrated that this butterfly is highly sensitive to “low-dose” internal exposure from field-contaminated host-plant leaves. These experimental results are fully consistent with the filed-collection results reporting high abnormality rates. In contrast, this butterfly is highly resistant against the internal exposure to chemically pure radioactive cesium chloride under laboratory conditions. To resolve this field-laboratory paradox, I propose that the field effects, which are a collection of indirect effects that work through different modes of action than do the conventional direct effects, play an important role in the “low-dose” exposure results in the field. In other words, exclusively focusing on the effects of direct radiation, as predicted by dosimetric analysis, may be too simplistic. In this chapter, I provide a working definition and discuss the possible variation in the field effects. I include an example on the misunderstanding of the field effects In the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) 2017 Report. Lastly, I discuss a theoretical application of the butterfly model to humans

DOES PHYSICAL EXERCISE INCREASE BRAIN-DERIVED NEUROTROPHIC FACTOR IN MAJOR DEPRESSIVE DISORDER? A META-ANALYSIS

Background: Major depressive disorder (MDD) is one of the most common disorders in the world, but is generally refractory to antidepressant treatment. However, physical exercise has been demonstrated to improve MDD symptoms, though the mechanism through which this is achieved is not clear. This systematic review and meta-analysis aimed to clarify whether physical exercise increased brainderived neurotrophic factor (BDNF) in patients with MDD to either establish or rule out this effect as a possible mechanism. Subjects and methods: We searched five electronic databases (PubMed, PsycINFO, CHINAL, Cochran Library, and Japanese Central Review of Medicine) for interventional studies released prior to 24 October 2017, examining the effects of physical exercise on BDNF in patients with MDD that compared the experimental group with an MDD control group. Those studies meeting the inclusion criteria were subjected to a meta-analysis in which changes of BDNF from baseline to post-exercise were quantified, with a standard mean difference and random effect model. Results: Five studies were eligible and included 199 participants. All articles included subjects with severe symptoms; three articles studied inpatient populations. All articles introduced aerobic exercise. We found no significant effect of physical exercise on BDNF levels (Z=0.32, p=0.75), and no heterogeneity (I2=0%). The risk of bias was moderate. Conclusions: We conclude that physical exercise does not significantly increase BDNF in patients with MDD. Thus, while increased BDNF has been shown to be beneficial in patients with MDD, physical exercise likely produces its benefits through a different mechanism. However, the small number of included articles and lack of multiple reviewers increase the risk of the result being a false negative