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Consciousness, reduction, and emergence. Some remarks.

Consciousness is often seen as requiring a special kind of explanation. But the various aspects of self-awareness can presumably emerge when certain levels of complexity are reached in an organism: it is not necessary to assume additional mechanisms or hidden causes. Looking at the most fundamental level, that of elementary particle physics, three principles appear--the conformability of nature to herself, the applicability of the criterion of simplicity, and the utility of certain parts of mathematics in describing physical reality--which are in themselves emergent properties of the fundamental laws of physics. At successive levels, it is the availability of similar mathematical descriptions from related problems that makes the next step appear with simplicity and elegance. Thus, once the concept of emergence is properly established, a huge burden is lifted from the inquiring mind. The whole explanatory loop may be closed by looking at the ability of the human mind to figure out the laws of nature. All the other sciences emerge in principle from fundamental physics plus historical accidents, even though "reduction" is obviously inadequate as a strategy. While bridges or staircases are under construction connecting the various sciences, each science needs to be studied at its own level as well. Although the idea of "vital forces" in biology alien to physics and chemistry has largely disappeared, consciousness remains the last refuge of obscurantists. Finally, it is argued that appeals to the alleged weirdness of quantum mechanics are based on a misunderstanding and are unlikely to have any place in a discussion of consciousness.

Animals↗

On the large-scale spectral structure of otoacoustic emissions.

Transient evoked and distortion product otoacoustic emission data, showing a characteristic slowly oscillating spectral shape, are presented. Such peculiar behavior had also been observed in earlier studies, and deserves some theoretical explanation. A simple model of the cochlear reflectivity, based on the analogy between the cochlear transmission line equations and the Schrödinger wave equation for the motion of an elementary particle above a one-dimensional potential well, is presented. Wave mechanics predicts indeed reflection from a negative potential well, which is quasiperiodically dependent on the width and depth of the well, i.e., on the quality factor of the cochlear resonance. The model, whose quantitative predictions are dependent on the rather uncertain level and slope of the cochlear tuning curve, proves capable of explaining, at least qualitatively, the observed experimental behavior.

Auditory Threshold↗

The dark halo of the milky Way

Most of the matter in the Milky Way is invisible to astronomers. Precise numbers are elusive, but it appears that the dark component is 20 times as massive as the visible disk of stars and gas. This dark matter is distributed in space differently than the stars, forming a vast, diffuse halo, more spherical than disklike, which occupies more than 1000 times the volume of the disk of stars. The composition of this dark halo is unknown, but it may comprise a mixture of ancient, degenerate dwarf stars and exotic, hypothetical elementary particles.

Journal Article↗

Big-bang nucleosynthesis and the baryon density of the universe.

For almost 30 years, the predictions of big-bang nucleosynthesis have been used to test the big-bang model to within a fraction of a second of the bang. The agreement between the predicted and observed abundances of deuterium, helium-3, helium-4, and lithium-7 confirms the standard cosmology model and allows accurate determination of the baryon density, between 1.7 x 10(-31) and 4.1 x 10(-31) grams per cubic centimeter (corresponding to about 1 to 15 percent of the critical density). This measurement of the density of ordinary matter is pivotal to the establishment of two dark-matter problems: (i) most of the baryons are dark, and (ii) if the total mass density is greater than about 15 percent of the critical density, as many determinations indicate, the bulk of the dark matter must be "non-baryonic," composed of elementary particles left from the earliest moments.

Astronomical Phenomena↗

MORPHOLOGY OF HUMAN GENITAL "T-STRAIN" PLEUROPNEUMONIA-LIKE ORGANISMS.

Ford, Denys K. (University of British Columbia, Vancouver, Canada), and Joyce Macdonald. Morphology of human genital "T-strain" pleuropneumonia-like organisms. J. Bacteriol. 85:649-653. 1963.-The morphology of Shepard's "T-strain" organisms from the human genital tract was investigated. The incubation of "T-strains" in 20% CO(2) with 80% nitrogen for 4 to 5 days caused surface outgrowth from the central core of the colonies embedded in the agar. Filtration through HA, PH, and VC Millipore filters showed that the elementary particles of "T-strains" were between 0.3 and 0.1 mu in diameter. "T-strain" pleuropneumonia-like organisms (PPLO) from broth cultures, stained by Giemsa's method, were seen to be minute, spherical particles, similar in size to the particles of the large-colony strains. Colonies of "T-strains," when prepared by the microculture, fixed-agar-block, and Formvar methods, resembled those of large-colony PPLO. It was concluded that "T-strain" organisms were true PPLO.

Agar↗

Deafferentation pain in man.

Pains of various etiologies are described in so many overlapping ways that verbal descriptions alone do not permit a valid distinction between those pains associated with neurological injury (with or without sensory loss) and those associated with neurological compression. Nor does the fact of some sensory loss plus pain constitute a useful classification to determine either the mechanism of the pain or its treatment. Progress is more likely to ensue if we seek to characterize in detail each type of painful lesion. Evidence for these conclusions is drawn from cases of brachial plexus injury, trigeminal rhizotomy and tractotomy, postcordotomy dysesthesia and central pain treated by regional guanethidine block. Examples of the value of totally innovative approaches are drawn from the physics of elementary particles.

Afferent Pathways↗

Pathomechanisms in rheumatoid arthritis--time for a string theory?

RA is a quintessential autoimmune disease with a growing number of cells, mediators, and pathways implicated in this tissue-injurious inflammation. Now Kuhn and colleagues have provided convincing evidence that autoantibodies reacting with citrullinated proteins, known for their sensitivity and specificity as biomarkers in RA, enhance tissue damage in collagen-induced arthritis (see the related article beginning on page 961). This study adds yet another soldier to the growing army of autoaggressive mechanisms that underlie RA. With great success researchers have dismantled the pathogenic subunits of RA, adding gene to gene, molecule to molecule, and pathway to pathway in an ever more complex scheme of dysfunction. The complexity of the emerging disease model leaves us speechless. It seems that with this wealth of data available, we need to develop a new theory for this disease. We may want to seek guidance from our colleagues in physics and mathematics who have successfully integrated their knowledge of elementary particles and the complexity of their interacting forces by formulating the string theory.

Animals↗

Focused X-shaped pulses.

The space-time focusing of a (continuous) succession of localized X-shaped pulses is obtained by suitably integrating over their speed, i.e., over their axicon angle, thus generalizing a previous (discrete) approach. New superluminal wave pulses are first constructed and then tailored so that they become temporally focused at a chosen spatial point, where the wave field can reach very high intensities for a short time. Results of this kind may find applications in many fields, besides electromagnetism and optics, including acoustics, gravitation, and elementary particle physics.

Journal Article↗

Physical bases for a triad of biological similarity theories.

The dimensional analysis of physics, based on the MLT-system (M = mass, L = length, T = time), can be applied to the living world, from mycoplasmas (10(-13) g) to the blue whales (10(8) g). Body mass (M), or body weight (W), are utilized as convenient reference systems, since they represent the integrated masses of all elementary particles--at the atomic level--which conform an organism. A triad of biological similarities (mechanical, biological, transport) have been previously described. Each similarity was based on two postulates, of which the first was common to all three, i.e., the constancy of body density; whereas the second postulates were specific for each of the three theories. In this study a physical foundation for these second postulates, based on three universal constants of nature, is presented, these are: 1) the acceleration of gravity (g = LT-2); 2) the velocity of light (c = LT-1); and 3) the mass-specific quantum (h/m = L2T-1). The realm of each of these biological similarities is the following: 1) the gravitational or mechanical similarity (where g = constant), deals mainly with the relationship between a whole organism and its environment, particularly with locomotion. The acceleration of gravity (g) is also one of the determining factors of the "potential" energy (E = m.g.H), where m is the mass, and H is the height above the reference level; 2) the electrodynamic similarity (formerly biological similarity), (c = constant), is able to quantitatively define the internal organization of an organism from both a morphological and a physiological point of view.(ABSTRACT TRUNCATED AT 250 WORDS)

Biological Transport↗

[Molecular computer. Biological physics and physics of the real world].

Any mind (man or computer) using Physical laws is a part of physical world, and thus it is necessary to correct physical laws for taking into account influence of the work of real limited computer on the predicted result. If we suppose that univerce was constructed to be supreme regular for mind, then this correction is negligible and on principle there is possibility to calculate relation between fundamental physical and biophysical constants. Two main principle are proposed: 1. The principle of minimum action and uncontrole influence of mind. 2. The maximum asymmetry of elementary particles, which are allowed by first principle. The first principle requires the upper and the lower limits for all physical values, and first of all the upper limit for velocity (c) and the lower limit for action (h). The second principle allows to construct the minimal physical elements for mind.

Biophysical Phenomena↗

[Cutaneous argyria: an electron microscopic study of four eases with microanalysis X study of one case (author's transl)].

This study was done in order to follow the fate of silver in the dermis of chronic argyria. Silver was easily recognizable in the tissue as irregular aggregates of elementary granules round or ovoid in shape, ranging from 30 to 40 mm in size. The microanalysis X showed that the metal was bound with sulfur. In the cases of recent intoxication, the main location of silver was intracellular: the granules were found in the lysosomes as elementary particle or as dense heterogen bodies. In the cases where intoxication had been stopped a long time ago, silver was found either on fibrillar component of the connective tissue or in the basal material of sweat glands. The results show that silver is at first phagocytized by macrophages but this cell is unable to perform complete degradation of the silver salt or metal. Then silver is found on connective fibers where it remains on sulfated glycoproteins.

Aged↗

[Is the "biopsychosocial model" a helpful construct?].

In 1977, G. L. Engel proposed a biopsychosocial model, applicable to all illness and disease. It was based on systems theory which orders the world into a ladder (of systems) from the most elementary particles to social phenomena and the cosmos. Systems theory was proposed to combat reductionism and to deal with complexity and order. Central to that theory is the concept of emergence that the properties of each "higher" or more complex system are not explainable either by their components nor by those at a lower level. However, no one form of complexity exists. Some forms of complexity arise out of the interactions of the components, especially as the result of feed-back, which in turn allows us to understand order, and sudden change. Living systems are characterized by genetic programs, self-replication, self-organization and adaptability. These properties exist at every "level", and thus make systems theory and its hierarchies no longer necessary, and also eliminate the concept of emergence.

Adaptation, Psychological↗

[Basic changes in neurons in the peripheral regions of the human nervous system during pathologic processes (electron microscopic study)].

Compensatory-adaptational and reparative reactions were studied in bodies, processes, receptors and synapses of the human peripheral nervous system and in the innervated substrate (myocardium, kidney, liver) by means of electron microscopy. An extreme increase of the electron density of macromolecular protein formations of specific elementary particles was revealed, in particular, in the outer layers of the hypertrophid mitochondria cryst membranes at 50000.000 magnification. These particles are considered as mitochondria precursors.

Cell Nucleus↗

NUCFRG2: a semiempirical nuclear fragmentation model.

The semiempirical abrasion/ablation model has been successful in generating a large nuclear data base for use in the study of high charge and energy (HZE) ion beams, radiation physics and galactic cosmic ray shielding. The cross sections generated agree with the measured HZE fragmentation data to the degree that different experimental groups agree among themselves. Several improvements in the model have been made including a Coulomb trajectory correction, an improved treatment of nuclear attenuation factors, an improved second order correction to the spectator fragment excitation spectrum, a pre-equilibrium emission process, and competitive equilibrium emission of additional hydrogen and helium isotope fragments.

Carbon↗

Search for projectile fragments with fractional charge in relativistic heavy ion collisions.

We measured the charge of about 35000 projectile fragments with Z > or = 5e produced by 14.5 GeV/nucleon and 200 GeV/nucleon 16O beams in a Pb target using CR39 plastic nuclear track detectors. A minimum track length of 3 mm in the detector without nuclear interaction was required. No evidence for fragments carrying a fractional charge was found.

Elementary Particle Interactions↗

Medium modified two-body scattering amplitude from proton-nucleus total cross-sections.

Recently (R.K. Tripathi, J.W. Wilson, F.A. Cucinotta, Nucl. Instr. and Meth. B 145 (1998) 277; R.K. Tripathi, F.A. Cucinotta, J.W. Wilson, NASA-TP-1998-208438), we have extracted nucleon-nucleon (N-N) cross-sections in the medium directly from experiment. The in-medium N-N cross-sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the NASA Langley Research Center. Here, we investigate the ratio of real to imaginary part of the two-body scattering amplitude in the medium. These ratios are used in combination with the in-medium N-N cross-sections to calculate total proton-nucleus cross-sections. The agreement is excellent with the available experimental data. These cross-sections are needed for the radiation risk assessment of space missions.

Aluminum↗