Mitochondrial abnormalities and oxidative imbalance in neurodegenerative disease

An increasing body of evidence now suggests the involvement of mitochondrial abnormalities in the etiology of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer disease. In this Perspective, we describe a recent study that shows that treatment of human patients with the antioxidant coenzyme Q(10'), which functions in concert with certain mitochondrial enzymes, reduced the worsening of symptoms associated with PD. These findings are consistent with the hypothesis that mitochondrial dysfunction plays a role in the pathogenesis of PD and that treatments that target mitochondrial biochemistry might ameliorate the functional decline observed in patients suffering from PD.     

Eradication of the melon fly,Dacus cucurbitae, from Kume is., Okinawa with the sterile insect release method

Summary The sterile insect release method was applied to eradicate the melon fly,Dacus cucurbitae, from the 58.5 km² island of Kume, in the Okinawa Islands group. Weekly releases of 1 to 1.5 million flies irradiated as pupae with 6–7 kR from a cobalt-60 source did not decrease the wild melon fly population. Releases of 1.5–2 million pupae per week made from September, 1975 to January, 1976 decreased the percent egg-hatch of females caught on Kume Is., but did not decrease the percent infestation significantly. The number of pupae released was increased from February, 1976 to accelerate the eradication process. When the number of pupae released exceeded 3.5 million per week, a rapid increase in the ratio of marked (sterile) to unmarked (wild) flies, a remarkable decrease in percent egg-hatch, and a decrease in percent infestation of fruits were observed. There has been no sign of melon fly infestation in wild cucurbit fruits from October, 1976 to the present time (April, 1977), despite the fact that more than 70,000 fruits were carefully examined. The eradication of the melon fly from Kume Is. was thus achieved by April, 1977, after the release of 264 million sterile fly pupae.     

Towards the Governance of Neuroscience: Neuroethics in Japan with Special Reference to Brain–Machine Interface (BMI)

Neuroscience in Japan has been rapidly growing during this decade. Interdisciplinarity and application oriented approach are two major tendencies of that. These are clearly observed in the recent launched big projects of neuroscience organized by departments and/or agencies of the Japanese government such as MEXT, NEDO and JST. We report the details of the project of Brain-machine Interface (BMI) as the typical example, which include research teams of ELSI and public relation besides the R&D bodies. Out trial of Benchside Research Ethics Consultation shows it is an effective and constructive way to realize mid-stream modulation of emerging technology. We also discuss how to bridge the gap between the expert and public perception for BMI.     

Effect of Particle Size on Risk Assessment of Direct Soil Ingestion and Metals Adhered to Children's Hands at Playgrounds

The quantity of heavy metals in soil is measured after 2‐mm sieving in Japan for risk assessment of direct soil ingestion. A study was conducted on the relationship between the size of soil particles and quantity of heavy metals in soil, and the particle‐size distribution of soil adhered to children's hands, and the risks of direct intake of soil considering the particle sizes ingested were evaluated. The results showed that smaller particles had a tendency to contain more heavy metals than bigger ones, that the particle size of approximately 90% of the soil particles from playgrounds adhered to children's hands was less than 100 μm, and that 2‐mm sieving in preparation for measuring heavy metal content caused underestimation of the risk of direct soil intake. The amount of heavy metals on children's hands after playing outside was investigated. Various metals and soil were adhered to their hands, and the amount of soil adhered could be estimated from the concentration of metals. To develop accurate risk assessment, the particle‐size distribution of ingested soil and more detailed scenarios of soil intake are necessary.     

Historical Demography: Achievements and Prospects

Historical demography as a separate discipline came into existence when family reconstruction was first developed for the analysis of a pre-transition population. This paper assesses the significant achievements made in this field of population studies since then. Attention is also paid to equally significant findings obtained from aggregative analysis based on back projection, and to a large body of research results for the period of the demographic transition. In the last part of the paper, new research directions are discussed. Data issues as well as methodological ones are raised. Special attention is given to newly emerging Asian historical demography where different source materials require different methods and techniques, which in turn are expected to broaden the scope of the so far disproportionality fertility-oriented field. Finally, discussions are extended to economic, cultural and institutional aspects of the subject, with a plea not to isolate demographic analysis from other branches of historical research.     

Stabilization of the population of a parasite on fruit by the population of a cleptoparasite

Summary When there exist two species such that one is a parasite on fruit and the other exploits the parasitized fruits, they must compete for a limited resource with each other. The relation betweenDacus cucurbitae andAtherigona orientalis is an example of such a situation. We raise a question whether the population of a parasite on fruit can be stabilized by the existence of the cleptoparasite of the parasite on fruit. The changes in their population densities are represented as a differential equation with time delayed parameters, which is deduced from the context of life histories of the two species. An index representing degree of overlapping of generations (g) is defined as an average oviposition period devided by the average preoviposition period, and the value is assumed to be the same in the two species. The stability of the system is classified by three parameters: the reproductive rate of the parasite on fruits (R), the survival probability of it through competition against the cleptoparasite (p), and the generation overlapping index (g). For small values ofg, e.g. less than some 0.5, the stability is determined mainly by a product ofRp: the values larger than 1 result in no equilibrium and infinite increase of both species, the values near 0 lead to large amplitude oscillations, and the intermediate values make stable equilibria or regular small oscillations. Asg takes the larger values, the stability region in the space (p, R) occupies the larger area. The model presented here is well adjusted to the fluctuating pattern of the population ofD. cucurbitae on Okinawa Is., and would also be applied to analysis of both hyperparasitisms and inquilin. This study was supported partly by Science Research Fund (No. 574092) from the Ministry of Education, Japan.     

Two simple characterizations of the Nash bargaining solution

We provide two alternative characterizations of the Nash bargaining solution. We introduce new simple axioms, strong undominatedness by the disagreement point, and egalitarian Pareto optimality. First, we prove that the Nash solution is characterized by symmetry, scale invariance, independence of irrelevant alternatives, and strong undominatedness by the disagreement point. Second, we replace the independence of irrelevant alternatives axiom with the sandwich axiom (Rachmilevitch in Theory Decis 80:427–442, 2016) and egalitarian Pareto optimality. We then demonstrate that the Nash solution is characterized by symmetry, scale invariance, strong undominatedness by the disagreement point, the sandwich axiom, and egalitarian Pareto optimality.     

Harsanyi's Social Aggregation Theorem and Dictatorship

In this paper I investigate the possibility of a dictatorship in the context of Harsanyi's Social Aggregation Theorem. Preliminarily, some propositions about Harsanyi's Theorem are presented using an alternative principle that I name Quasi-strong Pareto, which is the latter part of Strong Pareto. Then I define dictatorship as a requirement that social preference agrees with a dictator's preference or those of members of dictatorial group even if their preferences strictly contradict those of all other people in the society. Conclusively, although in each version of Harsanyi's Theorem with Pareto Indifference, Weak Preference Pareto or Weak Pareto the social utility function may have a form of dictatorship, however if individuals' vNM utility functions are all 'individualistic' and Quasi-strong Pareto is satisfied, then the dictatorship is excluded.