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PubMed2003

On the physics of the symbol--matter problem in biological systems and the origin of life: affine Hilbert spaces model of the robustness of the internal quantum dynamics of biological systems.

In the present paper, some physical considerations of the biological symbol-matter problem is exposed. First of all, the physical concept of quantum dynamical internal measuremental robustness is discussed. In this context, the significance of introducing affine molecular Hilbert spaces, the original (primordeal) internal quantum measurement, and the global constraining nature of time-inversion symmetry restoring, as a special restoration force, is discussed at some length. It is pointed out, as a summary, that global robustness of the internal dynamics of quantum measurements is due to two basic factors: on one hand, the global constraining nature of the chosen specific (symmetry-) restoring force, and on the other, the individual robustness of the discrete local internal measuremental interactions. The second condition is supposed to follow from a system-internalised ("objective") Bohr-type Copenhagen interpretation of quantum mechanics, corresponding, in an external context, to the Generalized Complementarity Principle of Bohr and Elsasser. It is not claimed, however, that this latter problem has been, as yet, satisfactorily settled physically. In fact, if it were, it would amount to a specifically biological quantum theory of internal measurement, which had to be rooted in the original primordeal global internal measurement, amounting to the origin of the genetic code.

Adaptation, Physiological↗
PubMed1976

Model consideration for the origin of life. Environmental structure as stimulus for the evolution of chemical systems.

In an attempt to understand the origin of living systems we encounter the following problems: How can we conceive the origin of the first self-reproducing forms, and by means of what stimuli could a constant increase in the complexity of such forms commence? How can a translation apparatus for genetic information develop? One cannot imagine that such an apparatus for the synthesis of enzymes can function alone without the interference of enzymes themselves, which, however, could only become available after the construction of the apparatus itself. What stimulus mechanism is conceivable that leads to the division of the genetic apparatus into a replication system, and an enzyme-synthesis system? The main problem therefore, is not the search for basic theoretical concepts. It is not a question which can be answered by means of specific experiments. One should rather explore the principal possibilities of how molecules combine to produce more and more complicated functional units. We look for the fundamental structural changes in the organizational systems and the driving forces initiating these developments. Questions concerning the detailed chemical realization are of secondary importance. In trying to solve the puzzle of how the genetic apparatus is gradually built up as complex aggregates of molecules, we consider a consistent causal chain of simple and transparent physiochemical model steps. The driving force for the self-organization of matter is seen in a specific environmental structure to be found on the surface of the earth. By this structure, which is periodic in time and heterogeneous in space, evolution is initiated and driven towards a continuously increasing degree of complexity correlated with a continuous expansion of the accessible living space. This process is a necessity under proper environmental conditions. Accidental events initiate each step but do not determine the general course of evolution which is determined by the selection mechanism.

Adenosine Monophosphate↗
PubMed1989

RNA evolution and the origins of life.

The evolution of RNA is likely to have played an important role in the very early history of life on Earth but it is doubtful that life began with RNA. Consideration of what came before RNA must take into account relevant information from geochemistry, prebiotic chemistry and nucleic acid biochemistry.

Biological Evolution↗
PubMed1994

The origin of life on the earth.

Growing evidence supports the idea that the emergence of catalytic RNA was a crucial early step. How that RNA came into being remains unknown.

Animals↗
PubMed1997

Combat trauma life support training versus the original advanced trauma life support course: the impact of enhanced curriculum on final student scores.

BACKGROUND: Within a military framework, the trauma course student, a young medical officer, is trained to become a trauma team leader and the first provider of medical aid. By adding battlefield medicine-related subjects to the basic Advanced Trauma Life Support (ATLS) course, as well as exercises tailored to the distinctive demands of military medicine, we could develop a special teaching unit: Combat Trauma Life Support (CTLS). The curriculum is basically the complete unchanged ATLS course of the American College of Surgeons enriched with lectures and practicums to fill the gap between the essentially civilian emergency department character of the ATLS course and the military tasks of the medical officer. PURPOSE OF STUDY: To compare the cognitive knowledge achievements of trauma course participants in the Israel Defence Force Medical Corps and to delineate the impact of the course type on students' written test results. DESIGN: A retrospective comparison analysis of pre- and post-course written test scores of 2,614 physicians who had participated in the ATLS and CTLS courses in the Israel Defence Force School of Military Medicine between 1990 and 1993. RESULTS: The analysis indicated that students who undertook the CTLS course achieved statistically better results in written tests (87.9 +/- 8.7 vs. 79.6 +/- 11.4, R2 = 0.33). CONCLUSIONS: We conclude that the CTLS comprehensive curriculum provides an improved training basis for the complex task of army battlefield trauma care support.

Curriculum↗
PubMed1986

Is there a single origin of life?

The emergence of the first life on the earth is now established as an early event, and closely related to the evolving earth. Laboratory experiments examining possible chemical events have revealed a multitude of plausible pathways. Lack of knowledge of the primitive terrestrial conditions contemporary with the evolving prebolic organic chemistry limits reconstruction techniques. The primitive earth's aqueous history is essential to unraveling this problem. Based on our current knowledge of other planets of the solar system, we do not expect close analogues to the early earth. We still do not know if there was a second origin or if only earth has life. This may depend upon the question of the survival of information bearing chemical systems in a dynamic or chaotic environment and the chemical protection afforded within such a system. Water is the central molecule of controversy: the blessing and the curse of the chemist. New and novel chemical mechanisms and systems abound.

Enzymes↗
PubMed1991

Handedness, origin of life and evolution.

Biological polymers have a preferred chirality ond can replicate themselves. Physical arguments provide insight into which of these unique and apparently related properties evolved first, and by what mechanism.

Alanine↗
PubMed2001

The origin of life. II: How did it begin?

The problem of how a mixture of chemicals can spontaneously transform themselves into even a simple living organism remains one of the great outstanding challenges to science. Various primordial soup theories have been proposed in which chemical self-organization brings about the required level of complexity. Major conceptual obstacles remain, however, such as the emergence of the genetic code, and the "chicken-and-egg" problem concerning which came first: nucleic acids or proteins. Currently fashionable is the so-called RNA world theory, which casts RNA in the role of both chicken and egg. Other theories assume that protein chemistry and even clay crystal life came before nucleic acids. To be fully successful, a theory of biogenesis has to explain not merely the emergence of molecular replication and chemical complexity, but the crucial information content and information processing capabilities of the living cell.

Animals↗
PubMed2003

The philosophy of Kitaro Nishida and current concepts of the origin of life.

The philosophy of Kitaro Nishida is a basic metaphysics that intends to have a perspective beyond both Eastern and Western traditions. Nishida holds that the fundamental reality of the world appears from "the place of the absolute nothingness." Nishida's thought can be seen to have striking relationships to certain aspects of contemporary science and philosophy.

Origin of Life↗
PubMed1978

Amino acid-directed nucleic acid synthesis. A possible mechanism in the origin of life.

The fact that proteins contain only alpha-amino acids and that protein structure is determined by 3' leads to 5' linked ribonucleotides is postulated to be the result of the copolymerization of these molecules in the prebiotic environment. Ribonucleotides therefore represent partial degradation products and proteins represent a side reaction developing from copolymerization. The basic structural unit of copolymerization is a nucleotide substituted with an amino acid at the 2' postion. Characteristics of modern amino and ribonucleic acid structure are all consistent with and necessary for this hypothesis. The characteristics and individual base assignemnts of the code also provide strong support for origin from the postulated copolymers. All characteristics of the code can be accounted for by this single hypothesis.

Amino Acids↗
PubMed1983

Chemical evolution and the origin of life.

During the last three decades major advances have been made in our understanding of the formation of carbon compounds in the universe and of the occurence of processes of chemical evolution. 1) Carbon and other biogenic elements (C,H,N,O,S and P) are some of the most abundant in the universe. 2) The interstellar medium has been found to contain a diversity of molecules of these elements. 3) Some of these molecules have also been found in comets which are considered the most primordial bodies of the solar system. 4) The atmospheres of the outer planets and their satellites, for example, Titan, are actively involved in the formation of organic compounds which are the precursors of biochemical molecules. 5) Some of these biochemical molecules, such as amino acids, purines and pyrimidines, have been found in carbonaceous chondrites. 6) Laboratory experiments have shown that most of the monomers and oligomers necessary for life can be synthesized under hypothesized but plausible primitive Earth conditions from compounds found in the above cosmic bodies. 7) It appears that the primitive Earth had the necessary and sufficient conditions to allow the chemical synthesis of biomacromolecules and to permit the processes required for the emergence of life on our planet. 8) It is unlikely that the emergence of life occurred in any other body of the solar system, although the examination of the Jovian satellite Europa may provide important clues about the constraints of this evolutionary process. Some of the fundamental principles of chemical evolution are briefly discussed.

Atmosphere↗
PubMed1998

The origin of life: self-replicating asymmetrical frozen probability.

Within each of us, as within each living or extinct creature, is a broad piece from the story of life and creation. Both the evolution of the universe and the emergence of life on Earth can be considered as being the result of critical events, such as phase transitions, that occur with a certain probability and are characterized by a sudden breakage of prior symmetry. These in turn result in self-perpetuating conditions that are responsible for what we know and perceive today.

Astronomical Phenomena↗
PubMed2005

Hypothesis: the origin of life in a hydrogel environment.

A hypothesis is proposed that the first cell(s) on the Earth assembled in a hydrogel environment. Gel environments are capable of retaining water, oily hydrocarbons, solutes, and gas bubbles, and are capable of carrying out many functions, even in the absence of a membrane. Thus, the gel-like environment may have conferred distinct advantages for the assembly of the first cell(s).

Biomimetic Materials↗
PubMed1977

The role of mineral surfaces in the origin of life.

Adsorption of nucleoside phosphates on the surfaces of volcanic rocks has been studied. Differences in the absorption of some nucleoside phosphates on the surface of basalt cinder have been found. Differences in the adsorption of similar molecules on different mineral surfaces have also been shown. Different adsorptive capacities may have served as a mechanism for the selection of organic molecules during prebiotic evolution.

Adenosine Diphosphate↗