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Origin and evolution of binucleate cells in cultures of HEp-2 cells.

The origin and evolution of binucleate cells in cultures of HEp-2 cells have been studied by means of interval photography and time-lapse video-recording. Binucleate cells most frequently formed by the fusion of two sister cells born in a previous mitosis. The study of binucleate cells has shown that they are a cellular type able to successfully undergo mitosis. However, the mitosis may be bipolar, tripolar or multipolar. The daughter cells arising from these divisions do not follow a clear pattern in the number of nuclei they have, instead showing a wide range of possibilities.

Carcinoma↗

Microcalorimetric investigations of the metabolism of yeasts. VII. Flow-calorimetry of aerobic batch cultures.

The heat evolution of aerobic batch cultures of growing yeast (Saccharomyces cerevisiae) in glucose media was investigated by a combination of a flow-microcalorimeter with a fermentor vessel. The course of heat production, cell production and the rate of oxygen consumption were qualitatively the same for all glucose concentrations between 10 mM and 100 mM. Under optimal aerobic conditions a triphasic growth was observed due to the fermentation of glucose to ethanol, respiration of ethanol to CO2 and acetate, and respiration of acetate to CO2. Energy and carbon were found to be in balance for all glucose concentrations.

Calorimetry↗

Culture, social minds, and governance in evolution.

In the past quarter century, the concept of culture has undergone change as evolutionary scientists have come to include social behavior in their purview. Evolutionary psychology is the newest field to concern itself with culture by claiming that most specific human behaviors are generated by minds specifically designed for these behaviors -- and not from a general-purpose mind -- as a result of adaptations made during the Pleistocene. Thus, mental behaviors are explained as having formed independently of cultural learning. In defending the concept, however, the leading proponents practically slough off culture as significant in human affairs. I argue that they have neglected the powerful explanatory statement of Darwin regarding at least one general-purpose adaptation of social animals, namely, the instinct for sociability, a position supported by recent neurological studies. Expanding the Darwinian concept, modern research shows that (1) the human brain was selected for sociability, which explains the origin and strength of culture, as well as its variability; (2) the development of complex culture in a pre-human primate initiated the two-and-one-half million-year evolution to modern humans; and (3) there are political contributions to cultural evolution that rest on the nature of groups (competitive and cooperative).

Journal Article↗

Working through a psychotherapy group's political cultures.

Macropolitical evolution, starting with authoritarian monarchism, has moved through anarchistic transitions either to the totalitarianism of fascism and communism or to liberal and social democracy. We posit analogous micropolitical development in process-oriented therapy groups: "dependence" and "counterdependence" corresponding to monarchism and anarchism; and "independence" and "interdependence" to liberal and social democracy, respectively. Transition from counterdependence to independence and interdependence may be: (1) facilitated through group members' cooperative experience of rebellion, or (2) blocked by collective identification, the internalization of dystopian or utopian fantasies that coalesce as "group-self" perceptions. We explore how group therapists work clinically with and through these several "political cultures" in the service of group and self transformation.

Defense Mechanisms↗

Third nature: the co-evolution of human behavior, culture, and technology.

Within a dynamical-systems framework, human behavior is seen as emergent from broad evolutionary processes associated with three basic forms of nature. First nature, matter, emerged from the big bang some 12-15 billion years ago; second nature, life, from the first bacteria up to 4 billion years ago; third nature, ideology and cultural artifacts (e.g., institutions and technology), with a shift to self-reflective, symbolic thought and agrarianism in humans some 8-40 thousand years ago. The co-evolution of these three natures has dramatically altered human behavior and its relationship to the whole planet. Third nature has infused human minds with several powerful ideas, or memes, including the idea of progress. These ideas have fueled the evolution of a complex institutional order (e.g., political systems and technology) and myriad attendant global problems (e.g., wars and environmental degradation). The human brain/mind is seen as the primary medium by which third nature governs human behavior and, therefore, self perpetuates.

Behavior↗

[Why should we research in bioethics?].

This article reviews the conceptual evolution of bioethics, conditioned by cultural changes. The discipline could be strengthened with new analytical methodologies and with an empirical approach. The dangers of a purely descriptive bioethics, solely linked to practical experience are also discussed. This may cause the loss of the regulatory frame, that allows bioethics to enrich medical practice from a humane and moral viewpoint. Therefore, there is a need to find the balance between the theoretical analysis and an empirical approach, to face the growing complexity of contemporary ethical problems.

Bioethics↗

Cultural niche construction and the evolution of small family size.

A model of cultural niche construction with two culturally transmitted traits is examined. The frequency of individuals with a certain general predisposition, which is transmitted vertically, plays a role as the cultural background, or the cultural niche, of the population. The cultural background determines the rate of oblique, relative to vertical, transmission of another cultural trait that affects fertility of individuals. It is assumed that individuals with fewer offspring are more likely to achieve social roles that influence the succeeding generation and are therefore overrepresented as transmitters in the process of oblique transmission. Our model suggests that even a slight overrepresentation of those with fewer offspring can drive the evolution of small family size, provided that the rate of oblique transmission depends strongly on the cultural background. In addition, our model may help to explain the time lag between the decrease in death rates and the subsequent decrease in birth rates during the demographic transition of industrializing societies.

Cultural Characteristics↗

[The patterns of the karyotypic evolution of cells in culture].

Numerous personal and literary data on the karyotypic variation of cell lines during their establishing and long-term culturing have been reviewed. A new notion about karyotypic evolutionary pathways of cells in culture is presented. A detailed original approach to cytogenetic study of permanent cell lines is given, which allows, via karyotype reconstruction, to obtain finally a new karyotypic characteristics-the generalized reconstructed karyotype (GRK). Application of the cytogenetic approach as a criterion for the control of authenticity, purity and stability of cell lines is discussed. The cell line analysis by means of GRK elicited that the cell line evolution in vitro passes through two stages: a stage of establishment, and a stage of stabilization, both differing in karyotypic variability of cell populations and clonal selection in culture. The data indicate that it is important in experiments to utilize cell lines being in the stage of stabilization and to characterize chromosomally the cell line at the same passage when it is used. Above all, a comparison of karyotypic variations of tumor and leukemic cells in vitro and in vivo has revealed their common karyotypic evolution regularities (a nonrandom character of numerical and structural chromosome changes and the loss of one of the sex chromosomes) and the karyotypic evolutionary regularities characteristic solely of cells in culture. The main of these being a balanced chromosome set in the cell population as a whole and obligatory retention of diploidy in all chromosomes of the normal set by the majority of human and animal cell lines. It has been revealed that no less than two homologs of each autosome are present in cells of at least 85% of examined lines. Other cell lines (at least 15%) of a generally neurogenic origin are shown to be notable by keeping partial or complete monosomies on autosomes throughout the long-term culturing. Peculiarities of the karyotypic evolution of the latter are regarded in detail in addition to the data on the expression of oncogenes and other growth-associated genes in their cells. It is suggested that there are three main compensatory mechanisms through which cell lines with autosomal monosomies may maintain the vitality in culture: polyploidization of initial cell clones, oncogene amplification, mainly of the myc-family oncogenes, and fragmentary or complete extracopying of several autosomes. In summary, perspective of cell line cytogenetics as a field of biology of the cell in culture is discussed.

Animals↗

Metabolism of Radiolabeled beta-Guaiacyl Ether-Linked Lignin Dimeric Compounds by Phanerochaete chrysosporium.

Phanerochaete chrysosporium metabolized the radiolabeled lignin model compounds [gamma-C]guaiacylglycerol-beta-guaiacyl ether and [4-methoxy-C]veratrylglycerol-beta-guaiacyl ether (VI) to CO(2) in stationary and in shaking cultures. CO(2) evolution was greater in stationary culture. CO(2) evolution from [gamma-C]guaiacyl-glycerol-beta-guaiacyl ether and [4-methoxy-C]veratrylglycerol-beta-guaiacyl ether in stationary cultures was two- to threefold greater when 100% O(2) rather than air (21% O(2)) was the gas phase above the cultures. CO(2) evolution from the metabolism of the substrates occurred only as the culture entered the stationary phase of growth. The presence of substrate levels of nitrogen in the medium suppressed CO(2) evolution from both substrates in stationary cultures. [C]veratryl alcohol and 4-ethoxy-3-methoxybenzyl alcohol were formed as products of the metabolism of VI and 4-ethoxy-3-methoxyphenylglycerol-beta-guaiacyl ether, respectively.

Journal Article↗

Coevolution of pathogens and cultural practices: a new look at behavioral heterogeneity in epidemics.

The effect of heterogeneity within populations on the spread of infectious diseases has been a recent focus of research. Such heterogeneity may be, for example, spatial, temporal or behavioral in form. Generally, models that include population subdivision have assumed that individuals are permanently assigned to given behavioral states represented by the subpopulations. We consider a simple epidemic model in which a behavioral trait affects disease transmission, and this trait may be transferred among hosts as a consequence of social interaction. This creates a situation where the frequencies of different behavioral traits and disease states as well as their associations may change over time. We consider the impact of the culturally transmitted trait on the criterion for initial spread of the disease. We also explore the evolution of cultural traits in response to pathogen dynamics and show some conditions under which behavioral traits that reduce transmission evolve. We find that behaviors increasing the risk of infection can also evolve when they are inherently favored or when there is sufficient clustering of contacts between like behaviors.

Communicable Diseases↗

Culture in whales and dolphins.

Studies of animal culture have not normally included a consideration of cetaceans. However, with several long-term field studies now maturing, this situation should change. Animal culture is generally studied by either investigating transmission mechanisms experimentally, or observing patterns of behavioural variation in wild populations that cannot be explained by either genetic or environmental factors. Taking this second, ethnographic, approach, there is good evidence for cultural transmission in several cetacean species. However, only the bottlenose dolphin (Tursiops) has been shown experimentally to possess sophisticated social learning abilities, including vocal and motor imitation; other species have not been studied. There is observational evidence for imitation and teaching in killer whales. For cetaceans and other large, wide-ranging animals, excessive reliance on experimental data for evidence of culture is not productive; we favour the ethnographic approach. The complex and stable vocal and behavioural cultures of sympatric groups of killer whales (Orcinus orca) appear to have no parallel outside humans, and represent an independent evolution of cultural faculties. The wide movements of cetaceans, the greater variability of the marine environment over large temporal scales relative to that on land, and the stable matrilineal social groups of some species are potentially important factors in the evolution of cetacean culture. There have been suggestions of gene-culture coevolution in cetaceans, and culture may be implicated in some unusual behavioural and life-history traits of whales and dolphins. We hope to stimulate discussion and research on culture in these animals.

Animals↗

The Mozart effect: tracking the evolution of a scientific legend.

Theories of the diffusion of ideas in social psychology converge on the assumption that shared beliefs (e.g., social representations, rumours and legends) propagate because they address the needs or concerns of social groups. But little empirical research exists demonstrating this link. We report three media studies of the diffusion of a scientific legend as a particular kind of shared belief. We studied the Mozart effect (ME), the idea that listening to classical music enhances intelligence. Study 1 showed that the ME elicited more persistent media attention than other science reports and this attention increased when the ME was manifested in events outside of science. Study 2 suggested that diffusion of the ME may have responded to varying levels of collective anxiety. Study 3 demonstrated how the content of the ME evolved during diffusion. The results provide evidence for the functionality of diffusion of ideas and initial elements for a model of the emergence and evolution of scientific legends.

Adolescent↗