16,055,313 research outputs found
Finite universe of discourse. The systems biology of Walter Elsasser (1904-1991).
No full textWalter Elsasser (1904-1991), an eminent quantum physicist and geophysicist, was also active in theoretical biology over a 35-year period from the early 1950s to the late 1980s. Although increasingly estranged from the biological establishment during the last fifteen years of his life, Elsasser's central concern with complexity has resulted in a revival of interest in his theories over the last decade, particularly among those who see biology from a systems holist rather than a molecular reductionist viewpoint. This article reviews the development of Elsasser's thought from his early opposition to genetic determinism, through the radical epistemology of his middle period, to his later more broadly philosophical ideas. After a summary of existing responses to Elsasser in the literature, a fresh critique and assessment of his work is presented, with particular attention to the implications for systems biology. It is concluded that although Elsasser drew some conclusions from his epistemology that are not justifiable in the light of subsequent research, his insistence on the existence of biotonic phenomena in biology, irreducible (either at present, or in principle) to physics, is correct. Ironically, the most significant biotonic principle is one which Elsasser largely ignored in his own work, that of Natural Selection
Jon Elsasser Interview, 2008
No full textJon Elsasser is the president of the Zoar Board of the Ohio & Erie Canal Association and Senior Vice President and Chief Information Officer at The Timken Company. Elsasser discusses Towpath Trail surfacing and bridge repairs after the 2005 flood and his hope that the trail will move beyond Zoar. He also discusses the semi-annual Civil War reenactment; town hall renovation; cemetery improvements; and other projects
First-principles analysis of cation segregation at grain boundaries in alpha-Al2O3
No full textThe modifications in atomistic structure, chemical bonding, and energetics induced by substitutional cation impurities isolated in the bulk volume and segregated at grain boundaries of alpha-Al2O3 were investigated by combining empirical ionic-model and first-principles electronic-structure calculations. The dependency of these modifications on the boundary type, species and concentration of impurities, was studied by selecting the following variety of systems: three twin boundaries (the prismatic Sigma3 (10 (1) over bar0), the rhombohedral Sigma7 (10 (1) over bar2), and the pyramidal Sigma13 (10 (1) over bar4) twins), three impurities X (X = Se, Y, and La), and two concentrations for the segregant ( approximate to3 and approximate to6 atoms/nm(2)). A partial covalent character is found to be a distinctive feature of the X-O bonds in both bulk and interfacial atomic environments, and to drive the structural distortions of the octahedral XO6 clusters. The energetics of segregation reveals a linear relationship between segregation energy and impurity size. This is interpreted as resulting from a stress field localized at the interface. (C) 2002 Published by Elsevier Science Ltd on behalf of Acta Materialia Inc
Breslau, Elsasser Strasse
No full textLantern slide of Elsasser Strasse in Wroclaw (formerly Breslau), Poland, circa 1905.https://research.library.kutztown.edu/lanternslideseducation/2202/thumbnail.jp
Die Elsasser: Rheinischer Merkur 1. 1814, Nr. 198 (!) [6.8.1814].
No full textDIE ELSASSER: RHEINISCHER MERKUR 1. 1814, NR. 198 (!) [6.8.1814].
Die Elsasser: Rheinischer Merkur 1. 1814, Nr. 198 (!) [6.8.1814]. ( -
Sigma 13 (10(1)over-bar4) twin in alpha-Al2O3: A model for a general grain boundary
No full textThe atomistic structure and energetics of the Sigma13 (10(1) over bar4)[1(2) over bar 10] symmetrical tilt grain boundary in alpha-Al2O3 are studied by first-principles calculations based on the local-density-functional theory with a mixed-basis pseudopotential method. Three configurations, stable with respect to intergranular cleavage, are identified: one Al-terminated glide-mirror twin boundary and two O-terminated twin boundaries, with glide-mirror and twofold screw-rotation symmetries, respectively. Their relative energetics as a function of axial grain separation are described, and the local electronic structure and bonding are analyzed. The Al-terminated variant is predicted to be the most stable one, confirming previous empirical calculations, but in contrast with high-resolution transmission electron microscopy observations on high-purity diffusion-bonded bicrystals. which resulted in an O-terminated structure. An explanation of this discrepancy is proposed based on the different relative energetics of the internal interfaces with respect to the free surfaces
Batılı gizli servislerden IŞİD’e giden yol
No full textJürgen Elsasser'in "Batılı Gizli Servislerden IŞİD’e Giden Yol" adıyla Türkçeye çevrilen kitabının tanıtımı
Pauli letter collection: letter to Walter M Elsasser
No full textPauli thanks Elsasser for his book "The Physical Foundation of Biology" and he discusses a few of its topics
Pauli letter collection: letter to Wolfgang Pauli
No full textElsasser replies to Pauli's letter concerning Elsasser's book. He clarifies several points criticized by Pauli
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