Spinor and Twistor Formulations of Tensionless Bosonic Strings in Four Dimensions

Spinor and twistor formulations of tensionless bosonic strings in 4-dimensional Minkowski space are constructed. We begin with a first-order action that is equivalent to the Nambu-Goto action in the tensionful case and that leads to a spinorial action in the tensionless case. From this spinorial action, we find an alternative spinorial action useful for constructing a simple twistor formulation of tensionless strings. The twistor formulation is steadily constructed in accordance with a fundamental concept of twistor theory. We investigate local internal symmetries inherent in the twistorial action for a tensionless string and carry out some classical analyses of the tensionless string expressed in a twistorial form.Comment: 30 pages, no figures, minor corrections, a footnote added, published versio

Extremely Strong ^{13}CO J=3-2 Line in the "Water Fountain" IRAS 16342-3814: Evidence for the Hot-Bottom Burning

We observed four "water fountain" sources in the CO J=3-2 line emission with the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope in 2010-2011. The water fountain sources are evolved stars that form high-velocity collimated jets traced by water maser emission. The CO line was detected only from IRAS 16342-3814. The present work confirmed that the ^{12}CO to ^{13}CO line intensity ratio is ~1.5 at the systemic velocity. We discuss the origins of the very low ^{12}CO to ^{13}CO intensity ratio, as possible evidence for the "hot-bottom burning" in an oxygen-rich star, and the CO intensity variation in IRAS 16342-3814.Comment: 10 pages, 3 figures, accepted for publication to the Publications of the Astronomical Society of Japan, Vol. 64, No.

Mixbiotic society measures: Assessment of community well-going as living system

Social isolation is caused by the impoverishment of community (atomism) and fragmentation is caused by the enlargement of in-group (mobism), both of which can be viewed as social problems related to communication. To solve these problems, the philosophical world has proposed the concept of "mixbiotic society," in which individuals with freedom and diverse values mix and mingle to recognize their respective "fundamental incapability" each other and sublimate into solidarity. Based on this concept, this study proposes new mixbiotic society measures to evaluate dynamic communication patterns with reference to classification in cellular automata and particle reaction diffusion that simulate living phenomena. Specifically, the hypothesis of measures corresponding to the four classes was formulated, and the hypothesis was validated by simulating the generation and disappearance of communication. As a result, considering communication patterns as multidimensional vectors, it found that the mean of Euclidean distance for "mobism," the variance of the relative change in distance for "atomism," the composite measure that multiplies the mean and variance of cosine similarity for "mixism," which corresponds to the well-going of mixbiotic society, and the almost zero measures for "nihilism," are suitable. Then, evaluating seven real-society datasets using these measures, we showed that the mixism measure is useful for assessing the livingness of communication, and that it is possible to typify communities based on plural measures. The measures established in this study are superior to conventional analysis in that they can evaluate dynamic patterns, they are simple to calculate, and their meanings are easy to interpret. As a future development, the mixbiotic society measures will be used in the fields of digital democracy and platform cooperativism toward a desirable society.Comment: 52 pages, 10 figure

Mixbiotic society measures: Comparison of organizational structures based on communication simulation

The philosophical world has proposed the concept of "mixbiotic society," in which individuals with freedom and diverse values mix and mingle to recognize their respective "fundamental incapability" each other and sublimate into solidarity, toward solving the issues of social isolation and fragmentation. Based on this concept, the mixbiotic society measures have been proposed to evaluate dynamic communication patterns with reference to classification in cellular automata and particle reaction-diffusion that simulate living phenomena. In this paper, we applied these measures to five typologies of organizational structure (Red: impulsive, Amber: adaptive, Orange: achievement, Green: pluralistic, and Teal: evolutionary) and evaluated their features. Specifically, we formed star, tree, tree+jumpers, tree+more jumpers, and small-world type networks corresponding to each of five typologies, conducted communication simulations on these networks, and calculated values for mixbiotic society measures. The results showed that Teal organization has the highest value of the mixism measure among mixbiotic society measures, i.e., it balances similarity (mixing) and dissimilarity (mingling) in communication, and is living and mixbiotic between order and chaos. Measures other than mixism showed that in Teal organization, information is not concentrated in a central leader and that communication takes place among various members. This evaluation of organizational structures shows that the mixbiotic society measures is also useful for assessing organizational change. In the future, these measures will be used not only in business organizations, but also in digital democratic organizations and platform cooperatives in conjunction with information technology.Comment: 25 pages, 6 figure

Rational Choice Hypothesis as X-point of Utility Function and Norm Function

Towards the realization of a sustainable, fair and inclusive society, we proposed a novel decision-making model that incorporates social norms in a rational choice model from the standpoints of deontology and utilitarianism. We proposed a hypothesis that interprets choice of action as the X-point for individual utility function that increases with actions and social norm function that decreases with actions. This hypothesis is based on humans psychologically balancing the value of utility and norms in selecting actions. Using the hypothesis and approximation, we were able to isolate and infer utility function and norm function from real-world measurement data of actions on environmental conditions and elucidate the interaction between the both functions that led from current status to target actions. As examples of collective data that aggregate decision-making of individuals, we looked at the changes in power usage before and after the Great East Japan Earthquake and the correlation between national GDP and CO2 emission in different countries. The first example showed that the perceived benefits of power (i.e., utility of power usage) was stronger than the power usage restrictions imposed by norms after the earthquake, contrary to our expectation. The second example showed that a reduction of CO2 emission in each country was not related to utility derived from GDP but to norms related to CO2 emission. Going forward, we will apply this new X-point model to actual social practices involving normative problems, and design the approaches for the diagnosis, prognosis and intervention of social systems by IT systems.Comment: 15 pages, 13 figures. Published online at http://redfame.com/journal/index.php/aef/article/view/4890 . Related to arXiv:2002.0903

Modeling SARS-CoV-2 infection and its individual differences with ACE2-expressing human iPS cells

ACE発現ヒトiPS細胞を用いたSARS-CoV-2感染の個人差再現と原因究明. 京都大学プレスリリース. 2021-04-19.Stem cells show gender differences in COVID-19 risk. 京都大学プレスリリース. 2021-04-19.Genetic differences are a primary reason for differences in the susceptibility and severity of COVID-19. As induced pluripotent stem (iPS) cells maintain the genetic information of the donor, they can be used to model individual differences in SARS-CoV-2 infection in vitro. We found that human iPS cells expressing the SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) (ACE2-iPS cells) can be infected w SARS-CoV-2. In infected ACE2-iPS cells, the expression of SARS-CoV-2 nucleocapsid protein, budding of viral particles, and production of progeny virus, double membrane spherules, and double-membrane vesicles were confirmed. We performed SARS-CoV-2 infection experiments on ACE2-iPS/ embryonic stem (ES) cells from eight individuals. Male iPS/ES cells were more capable of producing the virus compared with female iPS/ES cells. These findings suggest that ACE2-iPS cells can not only reproduce individual differences in SARS-CoV-2 infection in vitro but also are a useful resource to clarify the causes of individual differences in COVID-19 due to genetic differences

Sustainability and Fairness Simulations Based on Decision-Making Model of Utility Function and Norm Function

We introduced a decision-making model based on value functions that included individualistic utility function and socio-constructivistic norm function and proposed a norm-fostering process that recursively updates norm function through mutual recognition between the self and others. As an example, we looked at the resource-sharing problem typical of economic activities and assumed the distribution of individual actions to define the (1) norm function fostered through mutual comparison of value/action ratio based on the equity theory (progressive tax-like), (2) norm function proportional to resource utilization (proportional tax-like) and (3) fixed norm function independent of resource utilization (fixed tax-like). By carrying out numerical simulation, we showed that the progressive tax-like norm function (i) does not increase disparity for the distribution of the actions, unlike the other norm functions, and (ii) has high resource productivity and low Gini coefficient. Therefore the progressive tax-like norm function has the highest sustainability and fairness

High-resolution melting curve analysis for rapid detection of mutations in a Medaka TILLING library

<p>Abstract</p> <p>Background</p> <p>During the last two decades, DNA sequencing has led to the identification of numerous genes in key species; however, in most cases, their functions are still unknown. In this situation, reverse genetics is the most suitable method to assign function to a gene. TILLING (Targeting Induced Local Lesions IN Genomes) is a reverse-genetic strategy that combines random chemical mutagenesis with high-throughput discovery of the induced mutations in target genes. The method has been applied to a variety of plant and animal species. Screening of the induced mutations is the most important step in TILLING. Currently, direct sequencing or nuclease-mediated screening of heteroduplexes is widely used for detection of mutations in TILLING. Both methods are useful, but the costs are substantial and turnaround times are relatively long. Thus, there is a need for an alternative method that is of higher throughput and more cost effective.</p> <p>Results</p> <p>In this study, we developed a high resolution melting (HRM) assay and evaluated its effectiveness for screening ENU-induced mutations in a medaka TILLING library. We had previously screened mutations in the <it>p53 </it>gene by direct sequencing. Therefore, we first tested the efficiency of the HRM assay by screening mutations in <it>p53</it>, which indicated that the HRM assay is as useful as direct sequencing. Next, we screened mutations in the <it>atr </it>and <it>atm </it>genes with the HRM assay. Nonsense mutations were identified in each gene, and the phenotypes of these nonsense mutants confirmed their loss-of-function nature.</p> <p>Conclusions</p> <p>These results demonstrate that the HRM assay is useful for screening mutations in TILLING. Furthermore, the phenotype of the obtained mutants indicates that medaka is an excellent animal model for investigating genome stability and gene function, especially when combined with TILLING.</p