Stability, chaos and multiple attractors: A single agent makes a difference

This paper provides an example in which a slight behavioral heterogeneity may fundamentally change the qualitative properties of a nonlinear cobweb market with a quadratic cost function and an isoelastic demand function. We consider two types of producers; adaptive and naive. In a market of naive agents a single adaptive agent stabilizes the otherwise exploding market. In a market of adaptive agents a single naive agent may destabilize the market; without him there exists at most one periodic attractor in the market but with him there may appear many coexisting periodic attractors of arbitrarily large periods

A Compositional Data Analysis of Market Share Dynamics

The existing literature has shown that there are several statistical regularities in industrial dynamics, which are an important clue to understanding for the underlying mechanism. This paper focuses on market share changes and shows that its distribution has some remarkable properties. Because of the constrained nature of market share, that is, the sum must be unity, this paper applies the recently developed method called compositional data analysis (CDA) to market share data. We find the distribution does not follow a Gaussian but a tent-shaped distribution with a fatter tail, which is closely related with the findings of firm growth rate distribution. With some exceptions, this statistical feature can be observed across different sectors. Furthermore, this property can be observed when we focus on the relation between the top subgroup and lower-ranked firms. This shape of the distribution implies that market share growth cannot be described by an accumulation of small shocks: Rather, lumpy jumps that transform the market structure are crucial in market share dynamics. Put differently, radical change in market structure is a relatively frequent phenomenon. Such implications based on statistical properties of observed data help us further investigate industrial dynamics theoretically.departmental bulletin pape

Differentiated Duopoly Revisited

The present paper explores what happens in the analytical results of a duopoly model with product differentiation when heterogeneity of production cost is introduced. It is shown that there is a possibility that the price strategy is dominant over the quantity strategy even if goods are substitutes.石田孝造教授・關哲雄教授定年退任記念号departmental bulletin pape

Subclinical tuberculosis disease - a review and analysis of prevalence surveys to inform definitions, burden, associations and screening methodology

While it is known that a substantial proportion of individuals with tuberculosis disease (TB) present subclinically, usually defined as bacteriologically-confirmed but negative on symptom screening, considerable knowledge gaps remain. Our aim was to review data from TB prevalence population surveys and generate a consistent definition and framework for subclinical TB, thus enabling an estimate of the proportion of TB that is subclinical, explore associations with overall burden and programme indicators, and performance of screening strategies. We extracted data from all publicly available prevalence surveys conducted since 1990. Between 36.1-79.7% (median 50.4%) of prevalent bacteriologically-confirmed TB was subclinical. No association was found between prevalence of subclinical and all bacteriologically confirmed TB, patient diagnostic rate or country-level HIV prevalence (p-values, 0.32, 0.4, 0.34, respectively). Chest X-ray detected 89% (range 73-98%) of bacteriologically-confirmed TB disease, highlighting the potential of optimizing current TB case-finding policies

Utility of a Single Particle Isolation System in Genome-editing and Gene-transfection Experiments

In recent decades, genetic engineering and its application to medical sciences has been rapidly progressing, and gene transfection and genome-editing techniques are generally used even in medical investigations. Although establishing single-cell clones are essential for confirming the cellular phenotypic changes in association with genetic modifications, it is technically hard to dispense single-cell efficiently and correctly. Here, we demonstrate single-cell cloning of genetically modified lung cancer cells using a single particle isolation system, On-chip SPiS, by which bi-allelic gene-knockout cells and highly gene-expressing transfectants can be easily and certainly established. In our experiment, we obtained one bi-allelic knockout clone from only 12 clones（8.3％）and eight highly transgene-expressing clones from 20 clones（40％）. Furthermore, we could define that considerable rate of clones without transgene were mixed among selection marker-resistant cell populations. These results suggest that the single-cell dispensing system is a quite useful tool for single-cell cloning in genome-editing and gene-transfection experiments.journal articl

Subclinical Tuberculosis Disease-A Review and Analysis of Prevalence Surveys to Inform Definitions, Burden, Associations, and Screening Methodology.

While it is known that a substantial proportion of individuals with tuberculosis disease (TB) present subclinically, usually defined as bacteriologically-confirmed but negative on symptom screening, considerable knowledge gaps remain. Our aim was to review data from TB prevalence population surveys and generate a consistent definition and framework for subclinical TB, enabling us to estimate the proportion of TB that is subclinical, explore associations with overall burden and program indicators, and evaluate the performance of screening strategies. We extracted data from all publicly available prevalence surveys conducted since 1990. Between 36.1% and 79.7% (median, 50.4%) of prevalent bacteriologically confirmed TB was subclinical. No association was found between prevalence of subclinical and all bacteriologically confirmed TB, patient diagnostic rate, or country-level HIV prevalence (P values, .32, .4, and .34, respectively). Chest Xray detected 89% (range, 73%-98%) of bacteriologically confirmed TB, highlighting the potential of optimizing current TB case-finding policies

Gross Findings in Lymphadenectomy Specimens: Diagnosis and Differentiation of Malignant Lymphoma

In the diagnosis of malignant lymphoma (ML), lymphadenectomy specimens are separated as needed for histological diagnosis, flow cytometry, and various genetic analyses after determining the suitability of the specimens from gross findings. We investigated gross findings for cut surfaces of lymphadenectomy specimens. Of the 57 patients who underwent lymphadenectomies, 7 were diagnosed with reactive lymphoid hyperplasia (RLH), 19 with follicular lymphoma (FL), 20 with diffuse large B-cell lymphoma (DLBCL), and 11 with Hodgkin lymphoma (HL). The gross findings for fresh, unfixed lymph node specimens with the maximum cut surface were evaluated in terms of color homogeneity, unevenness of cut surface, aspect ratio, presence of internal nodules, and capsular disruption. After this evaluation, a histological diagnosis was performed. In a comparison of color homogeneity, significantly more cases in the ML group (30/50 [60.0%]) were homogeneous than in the RLH group (1/7 [14.2%]) (P = 0.039). Capsular disruption was not observed in the RLH group, whereas it was found in 42/50 (84.0%) cases in the ML group (P = 0.001). The internal nodules between the FL group (17/19 [89.5%]) and HL group (9/11 [81.8%]) occurred more frequently than those of the DLBCL group (11/20 [55.0%]) (P = 0.039). Moreover, the internal nodules tended to be smaller in FL and HL than in DLBCL (P = 0.007). The color homogeneity and capsular disruption findings were important in differentiating ML from RLH, and the presence and size of the internal nodules were important in differentiating the ML subtypes.journal articl