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The hydrophobic effect and the organization of living matter.

Biological organization may be viewed as consisting of two stages: biosynthesis and assembly. The assembly process is largely under thermodynamic control; that is, as a first approximation it represents a search by each structural molecule for its state of lowest chemical potential. The hydrophobic effect is a unique organizing force, based on repulsion by the solvent instead of attractive forces at the site of organization. It is responsible for assembly of membranes of cells and intracellular compartments, and the absence of strong attractive forces makes the membranes fluid and deformable. The spontaneous folding of proteins, however, involves directed polar bonds, leading to more rigid structures. Intercellular organization probably involves polar bonds between cell surface proteins.

Cell Compartmentation

Consciousness and the brain: evolutionary aspects.

Self-reflective consciousness is distinguished from 'simple' awareness and from conscious awareness. Awareness is a fundamental property of living matter as it reacts to environmental stimuli. A hypothesis is advanced to account for the general phenomenon of decussation of nerve fibres in the central nervous system of vertebrates. This feature, the crossing over of nerve fibres to the opposite side of the brain, is interpreted as exemplifying the inherent caution of living forms. The evolution of increasing complexity of structure in spinal cord and brain is a prerequisite for increasing awareness of the environment and for increasing freedom from its constraints. Conscious awareness is manifested in living forms primarily when they are learning to respond either to new stimuli or to internal demands such as breathing and walking. The relegation of learnt activities to the realm of unconscious reflex allows for concentration on new and more complex responses, which leads to further freedom of action. The seeming simplicity of human thinking rests on the increasing complexity of the evolving brain and of appropriate responses learnt during phylogenetic development. The human brain and its thinking functions are basically trustworthy because they are rooted in biological evolution.

Amoeba

[A scientific-cultural approach to the Gestalt concept].

In the descriptions of the gestalt process formulated by F. S. Perls (Gestalt Therapy Verbatim, Real People Press, Lafayette, 1969) and other gestalt psychologists, it appears as if the gestalt formation was a general and universal tendency of living and non living matter as well. Broadly speaking, they state that a gestalt is something that in itself wants to be formed and completed, something which emerges as a distinct entity (figure) from a undifferentiated environment (background). From experience we know that perceptions of any kind, have this as a prerequisite: the perceived object or process has to out of equilibrium with the environment, otherwise it remains undetectable. On the other hand, the second law of thermodynamics prescribes that the tendency for spontaneous isolated processes is exactly the opposite. With time, processes tend towards equilibrium, things tend to equalize, heterogeneity tends to become homogeneity, order into disorder. Thus these two very important "rules of the game" for natural processes are seemingly contradictory. While one states that matter tends to differentiate into figure and ground, the other states that exactly the opposite is what will occur - with time, all distinction and differentiation will disappear. Of the many problems posed by biological entities to the physical sciences, their obvious differentiation within the growth span of the organism, is a flagrant violation of the second law and hence they, as a whole, escape the realm of thermodynamics. Only living organisms can go against the second law. Living organisms tend to form gestalts and they perceive the world through the formation of gestalt pairs. However, the first man-made creature that knowingly could obviate the results prescribed by the second law, was Maxwell's Demon. He can produce heterogeneity from homogeneity since he can handle information. In Maxwell's hypothetical experiment, his Demon can pick out fast molecules from slow molecules taking a system initially in equilibrium to a new state in which there are differences. Information, in its mathematical context or neg-entropy is thus essential to systems that are out of equilibrium with their environment. In particular this is true of biological organisms. At an early stage genetic information is all that is required to produce differentiation. With growth and differentiation other forms of information come into play. From an engineer's point of view, energy without information does not serve in the production of work. From a psychotherapist's point of view, energy without information does not serve in the production of growth. In all schools of psychotherapy, the therapist can be considered as a Maxwell Demon; the outcome depending on the particular bias of his school. Gestalt Therapy with its strong emphasis on the "awareness of the ongoing process" relies heavily on all organismic functions as the means of producing information relevant to the patient...

Gestalt Theory

Synthesis of purine and pyrimidine bases and nucleosides under the cold plasma conditions (IX).

Living-matter precursors are obtained by the action of the high-frequency electrical discharges on a methane-ammonia-water mixture. Some purine and pyrimidine bases as well as nucleosides are detected and estimated quantitatively by column chromatography, one- and two-dimensional paper chromatography, paper chromatography with standard addition, colour tests as well as by optical density measurement within the UV region.

Ammonia

Dinferentiation in biology.

In this paper the authors give a survey of biological phenomena (both at the cellular level and in organisms), for which the term 'differentiation', used in the widest sense, has a meaningful application. The last chapter deals with some general aspects of differentiation and connected phenomena, such as polarity, symmetry, loss of potencies, dedifferentiation, redifferentiation, adifferentiation, regulation and integration. To prevent this article becoming too voluminous, the authors had to refrain from extending the treatment of differentiation to non-living matter and to human society.

Animals

The asymmetry of life.

Stereoselective physical phenomena and their possible importance for the prevalence of D-sugars and L-aminoacids in living matter are reviewed. A classification is presented according to which a selective force provides a microscopic or macroscopic selection depending on its generality when taken over a macrosystem (a 'unitary biosphere' such as the Earth). The microscopic 'selections' are not genuine selections because the final sense of asymmetry is here determined by chance, in other words the initial choice is 'random', while it is 'directed' in the macroscopic selection. Two macroscopic selections appear possible: 1. selection due to an intrinsic energy difference between enantiomorph configurations, 2. selection accomplished by elliptically polarised radiation.

Amino Acids

[Search for life on Mars].

The paper presents the data about the catalytic activity of several minerals from the Martian ground and of some laboratory analogues of the planet ground. It has been shown that it is possible to obtain unambigious data about life on Mars by using such methodological approaches which are based on biological principles of the determination of living matter. Microbiological methods for detection of extraterrestrial life should be preferred in future over biogeochemical methods which were used by the Viking stations.

Carbon Dioxide

[Coexistence of coacervate systems of different chemical composition].

Protein--nucleic acids--carbohydrate drops stabilized at pH 6.0 by the products of oxidative enzymes (polyphenol oxidase and peroxidase) were mixed with unstabilized ones. Using light, luminescent and electron microscopic techniques, a possibility was demonstrated of co-existence of coacervate drops with different chemical composition and formation of colonies from them. Coacervate drops are considered as a primitive form of cooperation of molecules in the course of the origin of the living matter. The results obtained will be used for obtaining more complex coacervate systems by imitation of a chain of catalytic reactions.

Biological Evolution

[Several methodologic problems of evolutionary histology in light of the findings of molecular genetics].

The paper elucidates certain methodological problems of evolutionary histology. The principal attention is given to the necessary synthesis of modern molecular biology and genetics and evolutionary histology. Modern data on the levels of the organization of the living matter and their significance for the rightness of the A.A. Zavarzin's theory of parallel lines in the tissue evolution are presented. The hypothesis of an application of the theory of parallel lines in the hereditary variability by N.I. Vavilov to the analysis of regularities of the tissue evolution is set forth. The hypothesis is proposed that mutation changes of similar genes in representatives of different types of animals underlie the regularities of the tissue evolution discovered by A.A. Zavarzin, and epigenomic changes of regulation systems occurring most frequently in the process of ontogenesis of organisms lie in the basis of the divergent evolution of tissues after N.G. Chlopin.

Biological Evolution

[Microorganisms in drugs and cosmetics - occurrence, harms and consequences in hygienic manufacturing (author's transl)].

The quantity of pharmaceutical and cosmetic products with different composition and the diversity of contaminating microorganisms set up special problems for each product with its specific field of application. It is not exact to generalize the hazard of contaminating microorganisms to product cathegories. Some product cathegories however are more imperilled to be contaminated with microorganisms and they are more hazardous than other ones. The most important component of the living matter is water that decides on growth, multiplication and survival of microorganisms in drugs and cosmetics. Products with a high content of available water are the most problematic ones. The consequences of survival and multiplication of microorganisms in relation to metabolic activity, pathogenicity and route of administration can be harmless or fatal. The nutritive wants of many microorganisms are very small, even simple salt solutions do not exclude microbial growth. There scarcely exist substrates not used as energy source by any microorganism and so it does not wonder that desinfectants are also used. Added preservatives may be absorbed or inactivated by suspended anorganic components, swelling agents, solubilizers etc., the containers or its closing. In the water phase of emulsions, in which under special conditions smaller amounts of the preservative are available, microorganisms sometimes can multiply. Skin care products neither belonging to pharmaceuticals nor to cosmetics present special clinical problems. Many times creams and lotions contain ingredients metabolized by microorganisms. Ointments and oils can be overgrown only by highly specialized organisms but if there is condensed water as a film at boundary surfaces much more microorganism species can grow. When using cosmetics it must be considered that parts of them will get into the eye. The eye is really endangered by Pseudomonads, which can according to the composition multiply in shampoos and whose contact to the eye can not be excluded. Syrups and solutions contain sugar concentrations, which suppress growth of most microorganisms except osmotolerant germs. Because of their low water content powders normally are protected against microbial growth but they should be free from clostridial spores for a mixture of powder and sweat is a good nutrient medium to Clostridia and fungi. Powders for surgical use must be sterile. Tablets and dragees do not allow microbial multiplication because of their low water activity. Under bad storage conditions a local increase of water content may permit microbial growth at the surface, especially in hygroscopicity. Fortunately there is seen a trend of not using multi-dose-containers for injections because of the high risk of contamination. It is to develop single-dose-containers also for other groups of preparations especially for eye-preparations. Many products microbiologically unobjectionable produced are contaminated in use, they contain the spectrum of microorganisms of the area of application...

Bacteria

Morphological instability and roughening of growing 3D bacterial colonies.

How do growing bacterial colonies get their shapes? While colony morphogenesis is well studied in two dimensions, many bacteria grow as large colonies in three-dimensional (3D) environments, such as gels and tissues in the body or subsurface soils and sediments. Here, we describe the morphodynamics of large colonies of bacteria growing in three dimensions. Using experiments in transparent 3D granular hydrogel matrices, we show that dense colonies of four different species of bacteria generically become morphologically unstable and roughen as they consume nutrients and grow beyond a critical size-eventually adopting a characteristic branched, broccoli-like morphology independent of variations in the cell type and environmental conditions. This behavior reflects a key difference between two-dimensional (2D) and 3D colonies; while a 2D colony may access the nutrients needed for growth from the third dimension, a 3D colony inevitably becomes nutrient limited in its interior, driving a transition to unstable growth at its surface. We elucidate the onset of the instability using linear stability analysis and numerical simulations of a continuum model that treats the colony as an "active fluid" whose dynamics are driven by nutrient-dependent cellular growth. We find that when all dimensions of the colony substantially exceed the nutrient penetration length, nutrient-limited growth drives a 3D morphological instability that recapitulates essential features of the experimental observations. Our work thus provides a framework to predict and control the organization of growing colonies-as well as other forms of growing active matter, such as tumors and engineered living materials-in 3D environments.

Models, Biological

Pitfalls to avoid: the Australian experience.

In this paper the major health problems facing Australia's Aboriginal population are reviewed and an attempt is made to assess the genetic and environmental, social and cultural factors to which they may be attributed. Among Aborigines living in remote areas under semi-tribal conditions, recent improvements in health, though considerable, have not been commensurate with the greatly increased expenditure on health and welfare services. This disappointing outcome is due partly to loss of control by Aborigines over their own lives, including matters concerning health, and partly to failure of white medical and welfare personnel to communicate with people holding different beliefs about health and disease. The bad health of Aborigines living in cities and rural areas can be attributed largely to their poverty, which in turn stems from discrimination in employment, housing and community services. In both the remote and the settled areas health services for Aborigines are increasingly coming under the control of Aborigines themselves and producing encouraging results.

Adult

Concurrent studies of the flow of digesta in the duodenum and of exocrine pancreatic secretion in calves. 5. The effect of giving milk once and twice daily, and of weaning.

1. The effects of giving milk once or twice daily (Expt 1) and of weaning (Expt 2) on the flow rate of digesta through the duodenum and on pancreatic secretion were studied in four and two Ayrshire calves respectively. The calves were prepared with duodenal re-entrant and pancreatic sac cannulas. 2. In Expt 1, when whole milk was offered ad lib. once daily, the calves ingested 141 g/kg live weight (46 g dry matter (DM)/kg live weight 0.75) at a single meal. The subsequent pattern of flow and total recovery of polyethylene glycol from the duodenum suggested that none of the ingested milk passed into the rumeno-reticulum. As the total daily quantity of milk ingested when the calves were fed once and twice daily was similar, it was concluded that abomasal distension is unlikely to be the sole factor limiting milk intake in the preruminant calf. 3. With twice-daily feeding, there were no differences in the pattern or total flow of fluid, electrolytes, nitrogen or fat through the duodenum of the calves following the 09.00 and 21.00 hours meals. The pattern of flow of duodenal and pancreatic fluids and the concentration of electrolytes, N and fat were markedly different when the calves were fed once or twice daily. The patterns of flow of fluid and the concentration of electrolytes in the duodenal digesta reflected the frequency of feeding and the size of the meal and the consequent balance between feed and endogenous components of the digesta. The quantity of the apparent endogenous secretion and pancreatic secretion was markedly less when the calves were fed once daily. 4. In Expt 2, the two Ayshire calves were given whole milk twice daily (diet MM), whole milk once daily with concentrates (diet MC), concentrates alone (diet CC) or dried grass alone (diet DG). The calves consumed 46, 49, 45 and 51 g DM/kg live weight 0.75 when given diets MM, MC, CC and DG respectively. 5. The twice-daily fluctuations in the flow and concentration of fluid, electrolytes, N and fat in the duodenal digesta and the pancreatic fluid observed when diet MM was given were replaced by relatively constant flow rates and composition when diet CC or DG was given. 6. Over the 24 h experimental period 97, 70, 50 and 58% of the DM and 112, 98, 99 and 84% of the N in the feed passed through the duodenum of calves when given diets MM, MC, CC and DG respectively. 7. When dry food was given, the rate of pancreatic fluid secretion was markedly lower (11.3 and 13.5 ml/kg live weight for diets CC and DG respectively) than when diet MM (19.7 ml/kg live weight) was given.

Animal Nutritional Physiological Phenomena

[Energy metabolism and energy requirements of growing boars].

The nitrogen and energy metabolism and the energy consumption of growing boars were measured in 2 metabolic and feeding trials using 8 parallel animals each. The studies covered the 30 to 150 kg live weight range. The growth intensity of the boars was found strongly influenced by the protein level of the ration. At a crude protein level of 18% in the ration, the boars gained, on the average, 780 g per day during the fattening period under study. Energy conversion was found to decline as the protein amount went up. The energy expediture for protein deposition was estimated at 1.8 to 2.0 kcal metabolizable energy per kg deposited. The energy and feed expenditures were calculated to be 7.1 Mcal net energy--fat retention for the whole development period or 3.0 kg dry matter per kg live weight. Boars proved to have an energy requirement differing from that of barrows and gilts; equations are presented for derivation.

Animals