Rethinking Ancient Maya Social Organization: Replacing "Lineage" with "House"

Long-standing disagreements concerning prehispanic Maya kinship and social organization have focused on the nature of their corporate groups, generally presumed to have been lineages. Specific debates center on whether the lineages were patrilineal or incorporated some kind of double-descent reckoning, how descent was combined with locality to define a group, and the status of lineage-outsiders within a group. It is argued here that Maya social organization is better approached within the contemporary critique of kinship, replacing "lineage" with Lévi-Strauss's model of the "house"—a corporate group maintaining an estate perpetuated by the recruitment of members whose relationships are expressed "in the language" of kinship and affinity and affirmed by purposeful actions. In this perspective, the operation of corporate groups is the primary concern, and relationships construed in terms of consanguinity and affinity are seen as strategies pursued to enhance and perpetuate the group, [ancestor veneration, house society, kinship, Maya, social organization]     

Ly-1 B helper cells in autoimmune "viable motheaten" mice

Previous work has demonstrated that Ly-1 B cells from normal C57BL/6J mice help the response of B cell subsets to the 4-hydroxy-3-nitrophenylacetyl hapten (NP). This regulatory cell population, called BH, preferentially helps the expression of plaque-forming B cells which express a predominant set of serologically related determinants collectively known as the NPb idiotype family. The specificity of BH cell activity in the NP system is a reflection of NPb idiotype-specific BH cell surface receptors. Thus, BH cells recognize autologous (i.e., idiotype) antigens. Given these observations and previous associations of increased Ly-1 B cell frequency in autoimmune mice, it was hypothesized that autoreactive Ly-1 BH cells may be present in high frequencies and in an activated state in autoimmune mice. To test this hypothesis the immunologic activity of BH cells in autoimmune viable motheaten (mev/mev) mice was studied. It was determined that splenic BH cells are approximately 10 times more frequent in viable motheaten than normal mice. The fact that BH cells from viable motheaten mice are activated was suggested by the presence of NPb idiotype-specific BH replacing helper activity in sera or B cell supernatants from these autoimmune mice. The soluble helper activities constitutively produced in mev/mev splenic B cell cultures and detected in mev/mev serum were resolved into two moieties, an NPb idiotype-specific immunoglobulin and a nonimmunoglobulin lymphokine(s) fraction. Purified mev/mev B cell-derived B cell maturation factor could substitute for the lymphokine moiety in the NPb idiotype helper cell assay. These results suggest that at least two signals, anti-idiotype immunoglobulin and a late-acting B cell maturation factor, are required for BH-dependent helper activity. The relationships of these results to current concepts of B cell activation mechanisms and the possible association of Ly-1 BH cells with autoimmunity are discussed.     

Nonlinear "hydrophobicity-antiesterase activity" model for various types of organophosphorous compounds

The dependence of antiesteratic activity on the structure of insecticides (RO)2P(O)SCH(COOEt)SP(O)(OR)2 (I) and (RO)2P(O)SCH(COOEt)OP(S)(OR)2 (II) was examined. Nonlinear regression equations (parabolic and bilinear) "hydrophobicity-antiesteratic activity" were derived. Basing on the studies of the relationships between hydrophobicity and individual constants, the detailed mechanisms were proposed for the interaction of type (I) and (II) compounds with the esterase active centers. The mechanisms implicate different kinds of sorbtion for compounds of type I and II. Applicability of bilinear models, similar to that of Kubinyi type, for analyzing the structure-antienzyme activity dependences was demonstrated. Thus, several equations were obtained starting from the literature data on inhibition of esterases with diverse organophosphorus compounds.     

Synthesis and antiviral activities of new acyclic and "double-headed" nucleoside analogues

To develop an understanding of the structure-activity relationships for the inhibition of orthopoxviruses by nucleoside analogues, a variety of novel chemical entities were synthesized. These included a series of pyrimidine 5-hypermodified acyclic nucleoside analogues based upon recently discovered new leads, and some previously unknown "double-headed" or "abbreviated" nucleosides. None of the synthetic products possessed significant activity against two representative orthopoxviruses; namely, vaccinia virus and cowpox virus. They were also devoid of significant activity against a battery of other DNA and RNA viruses. So far as the results with the orthopoxviruses and herpes viruses, the results may point to the necessity for nucleoside analogues 5'-phosphorylation for antiviral efficacy.     

The functions of the "Greeting Ceremony" among male mantled howlers (Alouatta palliata) on Agaltepec Island, Mexico

Nonhuman primates use greeting behaviors as nonaggressive communicatory signals in multiple social contexts. Adult male mantled howlers (Alouatta palliata) perform a ritual greeting that has been associated with bond-strengthening functions. The aim of this study is to explore the greeting patterns of male howlers living on Agaltepec Island, Mexico. Specifically, we analyzed the relationships between greetings and several individual, relational, and contextual variables, such as the expression of affiliation and agonism, dominance rank, age, kinship relationships, spatial organization, activity patterns, and subgrouping patterns. Greetings were more frequent between males with closer dominance ranks. Among those dyads that greeted at least once, dominant males initiated greetings more frequently than less-dominant males. On the other hand, more greetings were observed when one of the participants had recently returned to a subgroup and during locomotion. On the basis of these results, we propose that on Agaltepec greetings are a conflict management mechanism used between males of similar ranks. The fission-fusion social system of this group of howlers allows males with conflicting interests to remain separated, and greetings may reduce tension during fusion events.     

Pattern recognition methods for prediction of secondary structure of proteins. II. Elimination of "Contradicting" signs and prediction of turns of polypeptide chains in proteins.

A study is made of the relationships between electronic structures and carcinogenic activities of a series of molecules of which the parent is tricycloquinazoline. The carcinogens amongst these molecules do not belong to any of the better known classes of carcinogens and small variations between the members of the series produce marked differences in carcinogenic activity. Using semi.empiriW methods of pi-molecular orbital theory calculations have been carried out on the electronic structures of a number of the tricycloquinazdline series and the effect of substituents on the charge distribution is examined through the calculation of atom atom polarizabilities. The relation of these results to the carcinogenic behaviour of the tricycloquinazolines add the form of the variation of carcinogenic activity amongst the series of molecules under study is examined critically and the hypothesis that the specificity of tricycloquinazoline carcinogenesis could be due to electrostatic interactions between DNA base-pairs and tricycloqumazoline molecules intercalated into the DNA helix is formulated. Theoretical calculations to test this hypothesis are presented. Although the magnitudes of the electrostatic interactions are large enough to be significant, no general correlation in support of the hypothesis is found. Ionization potentials of tricycloquinazolines are also calculated and these support the view that there is no correlation between ionization potential and carcinogenic activity.     

The "image" of the regulatory gene in experiments with Drosophila

The mutants referred to as facultative dominant lethals were selected in the progeny of gamma-irradiated Drosophila males. The mutant males were viable and fertile, though their crosses with females of the yellow line yielded no daughters. The mutations obtained differed from the common mutations by (1) extremely varying penetrance of F1 hybrids from crosses with various lines; (2) the uncertain relationships between the mutant and normal alleles; (3) the different expression in somatic and germ cells; (4) the dependence of the expression on the sex of the parent carrying the donor mutations; (5) the mass morphosis formation and (6) the frequent reversal to the norm. These mutations are assigned to the regulatory group and their specific expression (see above) can be helpful in identifying regulatory gene mutations. We assume that the specific expression of the mutations studied is related to specific properties of the regulatory genes. These properties are as follows: (1) only one out of two homologous regulatory genes located on one homolog is in an active state, (2) in the haploid chromosome set the regulatory gene is represented by several alleles (cys-alleles); (3) only one allele ensures the regulatory gene activity.     

An even "newer" animal phylogeny

Metazoa are one of the great monophyletic groups of organisms. They comprise several major groups of organisms readily recognizable based on their anatomy. These major groups include the Bilateria (animals with bilateral symmetry), Cnidaria (jellyfish, corals and other closely related animals), Porifera (sponges), Ctenophores (comb jellies) and a phylum currently made up of a single species, the Placozoa. Attempts to systematize the relationships of these major groups as well as to determine relationships within the groups have been made for nearly two centuries. Many of the attempts have led to frustration, because of a lack of resolution between and within groups. Other attempts have led to "a new animal phylogeny". Now, a study by Dunn et al., using the expresssed sequence tag (EST) approach to obtaining high-throughput large phylogenetic matrices, presents an "even newer" animal phylogeny. There are two major aspects of this study that should be of interest to the general biological community. First, the methods used by the authors to generate their phylogenetic hypotheses call for close examination. Second, the relationships of animal taxa in their resultant trees also prompt further discussion.     

Distinguishing "or" from "and" and the case for historical identification

The adequacy of a probabilistic interpretation must be judged according to the nature of the event, or thing, being inferred. For example, conditional (frequency) probability is not admissible in the inference of phylogeny, because basic statements of common ancestry do not fulfill the requirements of the relations specified by the probability calculus. The probabilities of the situation peculiar to the time and place of origin of species are unique. Moreover, according to evolutionary theory, an event of species diversification is necessarily unique, because species are parts of a replicator continuum—species arise from ancestral species. Also, these probabilities cannot be ascertained, because the relevant situation cannot be repeated—it is unique. Finally, the applicability of conditional (frequency) probability is denied, because events of common ancestry have already occurred—there is nothing to predict. However, hypotheses of species relationships can be identified objectively according to the degree to which they have survived simultaneous testing with critical evidence, not with generally confirming evidence. The most parsimonious hypothesis of species relationships represents the least disconfirmed, best supported, proposition among the alternatives being compared. That hypothesis does not, however, deserve any special epistemological status beyond serving as the focus of the next round of testing.     

系统发育研究中“长枝吸引”现象概述

系统发育研究(phylogeny)不仅有助于重建地球所有生物体的进化历史, 而且还可以揭示进化生物学领域中的一些基本问题。清晰了解各生物物种进化历程及不同物种之间的进化关系, 是进一步研究和探索生物学其他学科的基础。但是现今广泛应用的所有系统发育分析方法都存在一定的局限性, 在一定程度上不能有效消除各种误差, 从而不能客观地处理和分析数据, 也就不能成功重建生物进化历程, 真实反映物种进化关系。系统发育研究中, “长枝吸引” (Long-branch Attraction, LBA)假象是最为困扰研究者的问题。文章从“长枝吸引”问题的产生原由、检测方法以及消除策略等多个方面进行详尽概述, 并通过列举典型实例, 阐述了解决“长枝吸引”问题的途径。     

Thiolactomycin inhibits d-aspartate oxidase: A novel approach to probing the active site environment

d-Aspartate oxidase (DDO) and d-amino acid oxidase (DAO) are flavin adenine dinucleotide (FAD)-containing flavoproteins that catalyze the oxidative deamination of d-amino acids. While several functionally and structurally important amino acid residues have been identified in the DAO protein, little is known about the structure–function relationships of DDO. In the search for a potent DDO inhibitor as a novel tool for investigating its structure–function relationships, a large number of biologically active compounds of microbial origin were screened for their ability to inhibit the enzymatic activity of mouse DDO. We discovered several compounds that inhibited the activity of mouse DDO, and one of the compounds identified, thiolactomycin (TLM), was then characterized and evaluated as a novel DDO inhibitor. TLM reversibly inhibited the activity of mouse DDO with a mixed type of inhibition more efficiently than meso-tartrate and malonate, known competitive inhibitors of mammalian DDOs. The selectivity of TLM was investigated using various DDOs and DAOs, and it was found that TLM inhibits not only DDO, but also DAO. Further experiments with apoenzymes of DDO and DAO revealed that TLM is most likely to inhibit the activities of DDO and DAO by competition with both the substrate and the coenzyme, FAD. Structural models of mouse DDO/TLM complexes supported this finding. The binding mode of TLM to DDO was validated further by site-directed mutagenesis of an active site residue, Arg-237. Collectively, our findings show that TLM is a novel, active site-directed DDO inhibitor that will be useful for elucidating the molecular details of the active site environment of DDO.     

Sequence requirements in the catalytic core of the "10-23" DNA enzyme

A systematic mutagenesis study of the "10-23" DNA enzyme was performed to analyze the sequence requirements of its catalytic domain. Therefore, each of the 15 core nucleotides was substituted separately by the remaining three naturally occurring nucleotides. Changes at the borders of the catalytic domain led to a dramatic loss of enzymatic activity, whereas several nucleotides in between could be exchanged without severe effects. Thymidine at position 8 had the lowest degree of conservation and its substitution by any of the other three nucleotides caused only a minor loss of activity. In addition to the standard nucleotides (adenosine, guanosine, thymidine, or cytidine) modified nucleotides were used to gain further information about the role of individual functional groups. Again, thymidine at position 8 as well as some other nucleotides could be substituted by inosine without severe effects on the catalytic activity. For two positions, additional experiments with 2-aminopurine and deoxypurine, respectively, were performed to obtain information about the specific role of functional groups. In addition to sequence-function relationships of the DNA enzyme, this study provides information about suitable sites to introduce modified nucleotides for further functional studies or for internal stabilization of the DNA enzyme against endonucleolytic attack.     

The meaning of the concept "ecological hazard"

Anthropogenic activity transforms the natural media and in the wide sense is a stimulus of further evolution. The late consequences of anthropogenic activity are mainly unpredictable. It is possible to acknowledge anthropogenic activity as ecologically hazardous only when it has a damaging effect on the health of man or interferes with its interests, i.e. while estimating it from egocentric positions. At present ecological hazards are first of all presented by industrial waste.     

Evaluation of the antioxidant activity of flavonoids by "ferric reducing antioxidant power" assay and cyclic voltammetry

Flavonoids, naturally occurring phenolic compounds, have recently been studied extensively for their antioxidant properties. The structure-antioxidant activity relationships (SAR) of flavonoids have been evaluated against different free radicals, but "ferric reducing antioxidant power" (FRAP) assay, which determines directly the reducing capacity of a compound, has not been used for this purpose. In this study, the antioxidant activities of 18 structurally different flavonoids were evaluated by FRAP assay modified to be used in 96-well microplates. Furthermore, their oxidation potentials were also measured, which were in the range of +0.3 V (myricetin) to +1.2 V (5-hydroxy flavone) and were in good agreement with FRAP assay results. Quercetin, fisetin and myricetin had the lowest oxidation potentials and appeared the most active compounds in FRAP assay and were 3.02, 2.52 and 2.28 times more active than Trolox, respectively. Indications were found that the o-dihydroxy structure in the B ring and the 3-hydroxy group and 2,3-double bond in the C ring give the highest contribution to the antioxidant activity.     

Men Who Are Called "Women" in Toba-Batak: Marriage, Fundamental Sex-Role Differences, and the Suitability of the Gloss "Wife-Receiver"

This article gives brief accounts of affinal relations, marriage, gender roles, and long-term lineage relationships among Toba Bataks of Samosir, north Sumatra, Indonesia. Ethnographic data, presented in tandem with data on the Kachin and similar cultures, are used to call into question the use of the term "wife-taker" as opposed to "wife-receiver," as it is generally employed with reference to the groom, his family, and lineage-mates, in glossing a major conceptual category of Southeast Asian hinterland societies that have preferred matrilateral cross-cousin marriage. It is argued that "wife-taker" is more distorting of Batak practice and of their system of values than "wife-receiver."     

"Post-residency disease" and the medical self: identity, work, and health care among doctors who become patients

Doctors who become patients due to serious illnesses face many challenges related to issues of identity, work, and professionalism. In-depth interviews with such doctors reveal the complex ways in which illness threatens identity in these professionals. In comparison with "medical student's disease," these doctors now exhibit "post-residency disease"-minimizing physical symptoms that are in fact present, leading to decreases in care sought. Doctors often feel they are somehow invulnerable to disease and have to remain strong, not burdening others. Many describe themselves as "workaholics," which can prove to be a double-edged sword, posing problems as well as providing benefits. This professional commitment could interfere with preventive health behaviors and with "practicing what they preach." Some view their illness with their "medical self" - as if they were a physician observing another patient rather than themselves. These doctors often support their approach by choosing a colleague as a doctor who will not challenge them, thereby establishing a "denial system" as opposed to a support system. These doctor-patients confront difficult issues of how much their physicianhood is an identity or an activity, illustrating the intricate relationships and tensions between work, identity, professionalism, and health in contemporary medicine.     

Seasonal variability of some biochemical parameters in the whitefish (<Emphasis Type="Italic">Coregonus muksun</Emphasis> and <Emphasis Type="Italic">Coregonus lavaretus</Emphasis>)

The base levels and seasonal variability of ethoxyresorufin-O-deethylase (EROD) activity, glutathione-S-transferase (GST) activity, reduced glutathione concentration (GSH) and phospholipids concentration (PhL) of Coregonus lavaretus (Linnaeus, 1758) and Coregonus muksun (Pallas, 1814) were investigated. The relationships between this biochemical markers, hepatosomatic index and seasonal growth were also examined.     

A metalloproteinase associated with gelonin, a "ribosome inactivating protein"

Gelonin, a single-chain protein which inactivates eukaryotic ribosomes, becomes split into peptides when incubated with SDS. During the chromatographic purification of gelonin on carboxymethylcellulose three overlapping peaks emerge in the gelonin elution region, containing three proteins with small differences in apparent molecular weight (31,500, 30,000 and 29,200). All three proteins are endowed with inhibitory activity on protein synthesis and with proteinase activity, although with different specific activities, and all three give rise to the same peptides upon incubation with SDS, suggesting that they are isoforms of gelonin. The gelonin-associated proteinase acts only on gelonin, while it is inactive on the most common substrates for endoproteinases. The proteolytic activity is not inhibited by inhibitors of serine- or SH-proteinases, while it is completely abolished by chelating agents. Divalent cations restore the proteolytic activity inhibited by EDTA. The stability of the proteinase activity on exposure of gelonin to extreme values of pH or to prolonged incubation has been investigated. The inhibitory activity on protein synthesis and the proteinase activity are differently affected by these treatments.     

"I'm worth more than that": trait positivity predicts increased rejection of unfair financial offers

Humans react strongly to unfairness, sometimes rejecting inequitable proposals even if this sacrifices personal financial gain. Here we explored whether emotional dispositions--trait tendencies to experience positive or negative feelings--shape the rejection of unfair financial offers. Participants played an Ultimatum Game, where the division of a sum of money is proposed and the player can accept or reject this offer. Individuals high in trait positivity and low in trait negativity rejected more unfair offers. These relationships could not be explained by existing accounts which argue that rejection behaviour results from a failure to regulate negative emotions, or serves to arbitrate social relationships and identity. Instead, the relationship between dispositional affect and rejection behaviour may be underpinned by perceived self worth, with those of a positive disposition believing that they are "worth more than that" and those of a negative disposition resigning themselves to "taking the crumbs from under the table".     

Body mass and foraging ecology predict evolutionary patterns of skeletal pneumaticity in the diverse "waterbird" clade

Extensive skeletal pneumaticity (air-filled bone) is a distinguishing feature of birds. The proportion of the skeleton that is pneumatized varies considerably among the >10,000 living species, with notable patterns including increases in larger bodied forms, and reductions in birds employing underwater pursuit diving as a foraging strategy. I assess the relationship between skeletal pneumaticity and body mass and foraging ecology, using a dataset of the diverse "waterbird" clade that encompasses a broad range of trait variation. Inferred changes in pneumaticity and body mass are congruent across different estimates of phylogeny, whereas pursuit diving has evolved independently between two and five times. Phylogenetic regressions detected positive relationships between body mass and pneumaticity, and negative relationships between pursuit diving and pneumaticity, whether independent variables are considered in isolation or jointly. Results are generally consistent across different estimates of topology and branch lengths. "Predictive" analyses reveal that several pursuit divers (loons, penguins, cormorants, darters) are significantly apneumatic compared to their relatives, and provide an example of how phylogenetic information can increase the statistical power to detect taxa that depart from established trait correlations. These findings provide the strongest quantitative comparative support yet for classical hypotheses regarding the evolution of avian skeletal pneumaticity.