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American children with reading problems can easily learn to read English represented by Chinese characters.

With 2.5 to 5.5 hours of tutoring, eight second-grade inner-city school children with clear reading disability were taught to read English material written as 30 different Chinese characters. This accomplishment eliminates certain general interpretations of dyslexia, for example, as a visual-auditory memory deficit. The success of this program can be attributed to the novelty of the Chinese orthography and to the fact that Chinese characters map into speech at the level of words rather than of phonemes. It is proposed that much reading disability can be accounted for in terms of the highly abstract nature of the phoneme (the critical unit of speech in alphabetic systems) and that an intermediate unit, such as the syllable, might well be used to introduce reading.

Child↗

"Killer" character does not influence the transmission of mitochondrial genes in Saccharomyces cerevisiae.

Three cytoplasmic genetic elements have been shown to be separate from mitochondrial deoxyribonucleic acid (DNA), [rho], in Saccharomyces cerevisiae: the killer character [k], omicron-DNA, and psi [psi]. Griffiths has suggested genetic interactions between [VENR] and [TETR] mutants possibly located on omicron-DNA and mitochondrial genetic markers, but possible interactions between the best characterized of the three, the killer character, and mitochondrial DNA have not been investigated. To test this we isolated cycloheximide-induced nonkiller segregants (NKS) of killer cells with suitable genetic markers and mated them in [k] x [k], [k] x [k], and (NKS) x (NKS) combinations. No differences in quantitative mitochondrial marker transmission between these groups were found in crosses illustrating the mitochondrial phenomena of bias, polarity, and suppressiveness. Our studies show that no intercellular interactions between [k] and (NKS) cells influence mitochondrial transmission genetics. Intracellular interactions between the smaller double-stranded ribonucleic acid of [k] and mitochondrial DNA also were not detected.

Chloramphenicol↗

Lysogenic conversion for multiple characters in a strain of Staphylococcus aureus.

Lysogenization of nonlysogenic strains of Staphylococcus aureus was performed with two different bacteriophages, LS1 and LS2, that were unable to plaque on any of the strains of S. aureus tested. Infection of recipient strains was achieved when protoplasts were inoculated with LS1 or LS2 or when bacterial cultures were simultaneously inoculated with a virulent phage together with LS1 or LS2. Lysogenization was demonstrated by changes in phenotypic characters of the host strain and by liberation of bacteriophages from the modified strains as shown by electron microscopic examination. The lysogenic strains differed from the host strains by the following characters: they were coagulase, deoxyribonuclease, and lipase negative; they were untypable by the basic set of phages; they did not ferment mannitol under anaerobic conditions; and they produced only l-(+)-lactic acid by glucose fermentation. Their cell walls contained less glycine and concomitantly more serine than those of the host strains. Furthermore, they were devoid of protein A. Conversely, some antigenic factors as well as the presence of ribitol in the cell wall teichoic acid, indicated a parental relationship between the host strains and the derived lysogenic ones. Phages LS1 and LS2 could be excluded from the lysogenic strains by invading phages, and the revertant nonlysogenic strains recovered all of the characteristics of the initial host strains. It was thus concluded that the phenomenon described was due to lysogenic conversion. The origin of phages LS1 and LS2 is discussed.

Cell Wall↗

Isolation and characterization of linear deoxyribonucleic acid plasmids from Kluyveromyces lactis and the plasmid-associated killer character.

Two linear deoxyribonucleic acid plasmids, designated pGK11 and pGK12, were isolated from the yeast Kluyveromyces lactis IFO 1267. pGK11 and pGK12 had molecular weights of 5.4 X 10(6) and 8.4 X 10(6), respectively. Both plasmids possessed the same density of 1.687 g/cm3, lighter than the densities of mitochondrial (1.692 g/cm3) and nuclear (1.699 g/cm3) deoxyribonucleic acids. A restriction map of pGK11 was constructed from digestions by EcoRI, HindIII, PstI, and BamHI. pGK12 was cleaved by EcoRI into seven fragments and by BamHI into two fragments K. lactis IFO 1267 killed Saccharomyces cerevisiae sensitive and killer strains and certain strains of Saccharomyces italicus, K. lactis, Kluyveromyces thermotolerans, and K. vanudenii. All K. lactis strains lacking the pGK1 plasmids were nonkillers. A hybrid was constructed between K. lactis IFO 1267 and a nonkiller K. lactis strain lacking the plasmids and subjected to tetrad analysis after sporulation. The killer character was extrachromosomally transmitted in all tetrads in association with the pGK1 plasmids. The double-stranded ribonucleic acid killer plasmid could not be detected in any K. lactis killer strains. It is thus highly probable that the killer character is mediated by the linear deoxyribonucleic acid plasmids. A single chromosomal gene was found which was responsible for the resistance to the K. lactis killer.

Ascomycota↗

Selection of characters for an Adansonian analysis of mycobacterial taxonomy.

Tests which are most frequently employed to provide characters for numerical analysis of bacterial taxonomy provide little differentiation among the slow-growing members of the genus Mycobacterium. A special scheme was proposed to deal with this problem. Characters were based, to some extent, on quantitative reactions to tests, and were defined, for each test, in terms of natural clustering behavior of a large collection of assorted strains. Inter- and intrataxon analyses were based on comparisons of reaction patterns with tentative hypothetical median strain patterns. This permitted the analysis of larger numbers of cultures than can be practically studied in a conventional n x n table.

Catalase↗

Faints, fits, and fatalities from emotion in Shakespeare's characters: survey of the canon.

OBJECTIVES: To determine how often Shakespeare's characters faint, fit, or die from extreme emotion; to assess Shakespeare's uniqueness in this regard; and to examine the plausibility of these dramatised events. DESIGN: Line by line search through modern editions of these late 16th and early 17th century works for accounts of characters fainting, fitting, or dying while under strong emotion and for no other apparent reason. DATA SOURCES: All 39 canonical plays by Shakespeare and his three long narrative poems; 18 similar works by seven of Shakespeare's best known contemporaries. RESULTS: 10 deaths from strong emotion are recorded by Shakespeare (three occur on stage); all are due to grief, typically at the loss of a loved one. All but two of the deaths are in the playwright's late works. Some deaths are sudden. Another 29 emotion induced deaths are mentioned as possible, but the likelihood of some can be challenged. Transient loss of consciousness is staged or reported in 18 cases (sounding like epilepsy in two) and near fainting in a further 13. Extreme joy is sometimes depicted as a factor in these events. Emotional death and fainting also occur occasionally in works by Shakespeare's contemporaries. CONCLUSIONS: These dramatic phenomena are part of the early modern belief system but are also plausible by modern understanding of physiology and disease. They teach us not to underestimate the power of the emotions to disturb bodily functions.

Death, Sudden↗

Genetic diversity among varieties and wild species accessions of pea (Pisum sativum L.) based on molecular markers, and morphological and physiological characters.

Random amplified polymorphic DNA, simple sequence repeat, and inter-simple sequence repeat markers were used to estimate the genetic relations among 65 pea varieties (Pisum sativum L.) and 21 accessions from wild Pisum subspecies (subsp.) abyssinicum, asiaticum, elatius, transcaucasicum, and var. arvense. Fifty-one of these varieties are currently available for growers in western Canada. Nei and Li's genetic similarity (GS) estimates calculated using the marker data showed that pair-wise comparison values among the 65 varieties ranged from 0.34 to 1.00. GS analysis on varieties grouped according to their originating breeding programs demonstrated that different levels of diversity were maintained at different breeding programs. Unweighted pair-group method arithmetic average cluster analysis and principal coordinate analysis on the marker-based GS grouped the cultivated varieties separately from the wild accessions. The majority of the food and feed varieties were grouped separately from the silage and specialty varieties, regardless of the originating breeding programs. The analysis also revealed some genetically distinct varieties such as Croma, CDC Handel, 1096M-8, and CDC Acer. The relations among the cultivated varieties, as revealed by molecular-marker-based GS, were not significantly correlated with those based on the agronomic characters, suggesting that the 2 systems give different estimates of genetic relations among the varieties. However, on a smaller scale, a consistent subcluster of genotypes was identified on the basis of agronomic characters and their marker-based GS. Furthermore, a number of variety-specific markers were identified in the current study, which could be useful for variety identification. Breeding strategies to maintain or enhance the genetic diversity of future varieties are proposed.

Genetic Markers↗

The evolution of growth trajectories and other complex quantitative characters.

Growth trajectories differ from many other quantitative characters in that they are characterized by a continuous function rather than by a finite number of discrete measurements. We review here recently developed methods for predicting the evolution of growth trajectories under the influence of natural or artificial selection. Using our method, analysis of genetic data from mice shows that the patterns of genetic variation arising from developmental processes impose constraints on evolution of growth trajectories. These constraints can be quantified to reveal the families of growth trajectories that can be produced by selection and those families that cannot. The data suggest there may be relatively few evolutionary degrees of freedom for growth trajectories despite the presence of abundant additive genetic variation to alter size and (or) growth rate at every age. The description of these constraints may be useful to both biologists who would like to determine the evolutionary options available to natural populations and to breeders who would like to alter growth trajectories to economically improve domesticated species. Our methods and conclusions can be generalized to other kinds of "infinite-dimensional" or complex characters, including morphological shapes and norms of reaction.

Age Factors↗

No character displacement for reproductive isolation between Drosophila bipectinata and Drosophila malerkotliana.

To test whether character displacement for reproductive isolation between Drosophila bipectinata and Drosophila malerkotliana exists, the degree of sexual isolation was measured between their sympatric and allopatric populations. Although the isolation indices vary in different crosses, the average isolation index for sympatric populations is very close to that for allopatric populations. This shows no difference in the degree of sexual isolation between sympatric and allopatric populations of D. bipectinata and D. malerkotliana. Thus there is no evidence for the existence of character displacement for sexual isolation between these two closely related sympatric species.

Animals↗

Stability of alexithymia and its relationships with the 'big five' factors, temperament, character, and attachment style.

BACKGROUND: Controversy still exists concerning the stability of the alexithymia construct. Also, although alexithymia has been found to be related in a theoretically meaningful way to other personality constructs such as the 'Big Five' factors, few studies have investigated its relationship with influential constructs such as temperament and character, and attachment security. METHODS: Two hundred twenty-one undergraduate and graduate students were administered the Toronto Alexithymia Scale (TAS-20), the State-Trait Anxiety Inventory (STAI), the Zung Depression Scale (ZDS), the Temperament and Character Inventory (TCI-125), the Big Five Questionnaire (BFQ), and the Experiences in Close Relationships (ECR) questionnaire. After 1 month, 115 participants completed again the TAS-20, STAI, and ZDS. RESULTS: Alexithymia was only moderately correlated with depression and anxiety. Both the absolute and relative stability of TAS-20 total and subscale scores was high, and a negligible portion of their change over time was accounted for by changes in depression or anxiety. In separate multiple regression models including also gender, age, depression and anxiety, TAS-20 total and subscale scores were correlated with low energy/extraversion, low emotional stability, openness, low friendliness/agreeableness; harm avoidance, low self-directedness, low cooperativeness, low reward dependence; attachment-related avoidance and anxiety. CONCLUSIONS: Our findings lend support for both absolute and relative stability of alexithymia, corroborate an association between alexithymia and insecure attachment, and contribute to a coherent placing of alexithymia in the broader theoretical network of personality constructs.

Adolescent↗

Brain traits through phylogeny: evolution of neural characters.

We have previously derived a hypothetical tree of the lines of mammalian descent, based upon a comprehensive numerical taxonomic cross-analysis of primitive and derived states of 15 brain traits in 38 representative species. In this communication we use this tree to describe the probable sequence of changes that have taken place in phylogenetic history. 2 characters proved to be multiply convergent, occurring in parallel in several disparate lines of descent. The remaining 9 characters each appeared in ancestors of one or another of the lineages and characterize related progeny.

Animals↗

Genetical distance and dermatoglyphic characters. I. Interpopulation distance coefficients.

The distance coefficients between two relatively isolated population groups in Poland, based on various combinations of dermatoglyphic non-measurable characters were estimated. These were compared with the overall dermatoglyphic distance coefficients estimated separately for left and right, as well as with the serologic distance coefficient, based on ABO, Rh and Duffy blood groups. Dermatoglyphic distance coefficients, estimated from quantitative variables (pattern intensities) using Penrose's C2H analysis of variance method, were also introduced for a comparison. The differences in frequencies between two populations, separately for each character, were also compared with its heritability values.

ABO Blood-Group System↗

Genetical distance and dermatoglyphic characters. II. Intrapopulation distance coefficients.

This paper attempts to evaluate the dermatoglyphic (genetical) distance between two Polish population samples in relation to the intrapopulation distance coefficients estimated within each sample. All the coefficients have been based, in turn, on frequencies of fingertip, palmar and sole pattern elements, separately and for all characters combined. The results of a comparison of various combinations of dermatoglyphic characters with one another in respect of all successive values of a distance coefficient indicate that, if populations of mostly related individuals were compared, sole patterns have been the most efficient ones in differentiating between the two normal population samples. The values of inter- and intrapopulation distance coefficients obtained from samples consisting mostly of family units have been compared with those estimated in samples of non-related individuals. The limitations and difficulties in the interpretation of the values of a distance coefficient related both to the material used and statistical procedures are discussed.

Dermatoglyphics↗

Search for linkage between dermatoglyphic sole characters and blood groups.

A sample of 539 Polish families and 1,500 individuals were analysed to determine whether there was any suggestion of linkage between the dermatoglyphic characters and the blood groups. Provisional evidence for linkage between certain dermatoglyphic characters on the sole and the ABO blood groups has been obtained.

ABO Blood-Group System↗

A phylogeny of gibbons (Hylobates spp.) based on morphological and behavioural characters.

A new estimate of the phylogenetic relationships among the nine gibbon taxa is presented, based on a compatibility analysis of 55 morphological and behavioural characters. The phylogeny presented here differs somewhat from those of other studies, but there appears to be a basic consensus that: the siamang and concolor gibbons represent the earliest forms to speciate; the agile, lar, moloch, Müller's, and pileated gibbons represent the lates forms to speciate; with the Kloss and hoolock gibbons representing intermediate forms. Although the hypotheses regarding the evolutionary direction of these characters remain subjective due to the lack of gibbons in the fossil record, the method used is totally objective in its approach and is repeatable when further data become available.

Animals↗

Evolving learnable neutral networks under changing environments with various rates of inheritance of acquired characters: comparison between Darwinian and Lamarckian evolution.

The processes of adaptation in natural organisms consist of two complementary phases: learning, occurring within each individual's lifetime, and evolution, occurring over successive generations of the population. In this article, we study the relationship between learning and evolution in a simple abstract model, where neural networks capable of learning are evolved using genetic algorithms (GAs). Individuals try to maximize their life energy by learning certain rules that distinguish between two groups of materials: food and poison. The connective weights of individuals' neural networks undergo modification, that is, certain characters will be acquired, through their lifetime learning. By setting various rates for the heritability of acquired characters, which is a motive force of Lamarckian evolution, we observe adaptational processes of populations over successive generations. Paying particular attention to behaviors under changing environments, we show the following results. Populations with lower rates of heritability not only show more stable behavior against environmental changes, but also maintain greater adaptability with respect to such changing environments. Consequently, the population with zero heritability, that is, the Darwinian population, attains the highest level of adaptation to dynamic environments.

Algorithms↗

Character of the hard tooth tissue-polymer bond. I. Study of the interaction of calcium phosphate with N-phenylglycine and with N-phenylglycine-glycidyl methacrylate adduct.

A model investigation was carried out to establish the chemical character of the bond between hard tooth tissues and polymeric materials. The interaction of NPG and NPG-GMA with Ca3(PO4)2 and 45Ca3(PO4)2 was studied in aqueous, alcoholic and aqueous-alcoholic solutions. It was shown that NPG and NPG-GMA react in solution with Ca ions which are in equilibrium with calcium phosphate. The reaction proceeds more intensively in aqueous-alcoholic medium due to its ionic character. The IR spectra of the reaction products show the presence of NPG-GMA calcium salt.

Acrylates↗