Extremes of geometric variables with applications to branching processes

We obtain limit theorems for the row extrema of a triangular array of zero-modified geometric random variables. Some of this is used to obtain limit theorems for the maximum family size within a generation of a simple branching process with varying geometric offspring laws.Comment: 12 pages, some proofs are added to the published versio

Dewey's unprincipled philosophy: pragmatism against the Kantian tradition

Bibliography: p. 123-128

一般分枝過程の個体群動態諸問題への応用的研究

金沢大学理学部分枝過程の生物個体群動態への応用として,以下のような問題について知見を得た.1.Multiply-controlled branching processを用いて,密度依存の遅れと動態の周期的変動との関係.2.Controlled branching processを用いて,個体群の密度依存性と動態安定性の関係.3.General continuous branching processを用いて,一種個体群の齢構成と増殖率および生存曲線との関係.4.Simple branching processを同時に多数用いて,一生態学的群集の構造と環境のランダム変動および移入率との関係.5.ランダム環境下のNear-critical branching processを応用して,ミトコンドリア・イヴの年代推定への環境変動の影響.これらの結果の一部は著書「確率過程と数理生態学」にも取り入れることができた.以上で得られた知見は数学的にはまだ明らかにされていないことが多いが,コンピュータシミュレーションを活用することで得られたものである.今後,これらの問題をさらに発展的にかつ数学的にも研究を進めることは課題である.これまでの研究から分枝過程は個体群動態など生態学に限らず,DNA分子のPCR増殖法などより広く生命科学の諸問題に応用可能でありかつ有意義であることを認識した.このようなことから金沢で開催した研究集会「確率過程と数理生物学」(広島大学の瀬野裕美氏に企画を依頼)は今後の研究発展のために大変有意義であったと考える.Branching processes have been applied to the problems in biological population dynamics, and we have had some knowledge for the following problems.1.The relationship between periodic population growth and a delayed density-dependenxe.2.The relationship between an age-structure of population and a population growth rate as well as a survivorship curve.3.The relationship between ecological communities and random environmental variations.4.The effect of random environments on the age estimation of our most recent common ancestor.Part of the results are included in the monograph titled as "Random Processes and Mathematical Ecology" (in Japanese) by the head investigator T.Fujimagari. Most of the knowledge studied for the above problems were results through computer simulations. So, their mathematical analyses are to be studied hereafter.We realize the importance of the other applications of branching processes to various problems in life science such as an efficiency estimation of PCR of DNA molecules. The meeting "Random Processes and Mathematical Biology" which was held in Kanazawa in Autumn, 2002, with the aids of H.Seno at Hiroshima University was quite meaningful to develop the probabilistic studies of the problems in life science.研究課題/領域番号:14540109, 研究期間(年度):2002-2003出典：研究課題「一般分枝過程の個体群動態諸問題への応用的研究」課題番号14540109（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/report/KAKENHI-PROJECT-14540109/145401092003kenkyu_seika_hokoku_gaiyo/）を加工して作

Altered erythrocyte protein kinase C activity and membrane protein phosphorylation in chronic myelogenous leukemia

The membrane protein kinase C (PKC) content was found to be higher in erythrocytes form patients suffering from chronic myelogenous leukemia (CML) compared to normal erythrocytes. PKC activity was also higher in the cytosol and after translocation to the membrane, as assessed by histone phosphorylation. The increased PKC activity in CML erythrocytes was associated with abnormal phosphorylation of protein 4.1. Since phosphorylation-dephosphorylation mechanisms are likely candidates for controlling membrane protein associations, the altered PKC activity may be one of the factors responsible for altered thermal sensitivity and mechanical stability of CML erythrocytes

Supplementary Material for: Expression Profile of NOTCH3 in Mouse Spermatogonia

<p>Stable and sustainable spermatogenesis is supported by the strict regulation of self-renewal and differentiation of spermatogonial stem cells (SSC), which are a rare population of undifferentiated spermatogonia. It has been revealed that some signaling factors regulate the self-renewal of SSC; however, the molecular mechanism of SSC maintenance is still not completely understood. Notch signaling is an evolutionarily conserved juxtacrine signaling that plays important roles in the cell fate determination of various tissue stem cells. Recently, analyses of loss- and gain-of-function suggested that Notch signaling was necessary for normal spermatogenesis. However, the expression of Notch signal components in spermatogonia is still unclear. Here, we analyzed the distribution of NOTCH3-expressing spermatogonia and the target genes. Double immunostaining with differentiation markers revealed that NOTCH3 was expressed in some undifferentiated and differentiated spermatogonia in mouse testes. To define the target gene of Notch3 signaling in spermatogonia, we analyzed the mRNA expression pattern of <i>Hes</i> and <i>Hey</i> family genes during testis development. <i>Hes1</i> abundance was decreased during testis development, suggesting that spermatogonia may express <i>Hes1</i>. Immunohistochemical analysis showed that HES1 was expressed in prepubertal spermatogonia, whereas it was expressed predominantly in adult Sertoli cells and weakly in adult spermatogonia. Furthermore, NOTCH3-HES1 double-positive spermatogonia were in pup and adult testes. These results suggest that Notch3 signaling in spermatogonia could promote <i>Hes1</i> expression.</p