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PubMed1962

Genetic characters of human gamma-globulins in myeloma proteins.

The genetic factors Gm(a), Gm(b), Gm(x), and Inv(a), Inv(b) described for normal human gamma-globulin were all found in different myeloma proteins. A single myeloma protein never contained more than one product of alternate alleles even in heterozygous individuals. However, factors determined by the two different loci were often found in the same myeloma protein. The Gm(a) character of the myeloma protein parallelled that of the normal gamma-globulin of the same serum in most cases. In contrast, the Gm(b) character was usually absent in the myeloma protein when it was directly demonstrable in the normal gamma-globulin. The myeloma proteins from six Negroes were Gm(a+b-), whereas the normal gamma-globulin was Gm(a+b+). This indicates that the effect of gene Gm(b) is similar in Negroes and whites, even though its relation to gene Gm(a) is different in the two races. Gm factors were found only in the 7S gamma-globulin type myelomas and not in other products of plasma cell tumors. Inv characters were, however, present in all four types of proteins studied, namely 7S and 19S gamma-globulins, beta(2A)-globulins, and Bence Jones proteins. In two instances, genetic heterogeneity of the protein products was demonstrated suggesting the proliferation of more than one clone of plasma cells in some multiple myeloma patients. The accumulated evidence obtained in this study strongly suggested that the presence and absence of genetic characters was compatible with the concept that myeloma proteins were closely analogous to individual moieties in the spectrum of normal gamma-globulins rather than truly abnormal proteins. Their study offered evidence of a heterogeneity of genetic characters among the normal gamma-globulins in a given individual. It also appears probable that in normal individuals single plasma cells have a restricted capacity to express genetic information in their protein product.

Bence Jones Protein↗
PubMed1990

A character separation index suitable for binary data containing equivocal responses.

Character separation indices are useful for determining which binary characters best discriminate between two populations. To date these indices are unable to cope sufficiently with binary data that contain equivocal responses. A character separation index is described which can be applied to data containing equivocal responses. Furthermore, for larger numbers of group members this index can be used to derive the significance that a given character would have given a particular separation value by change. The BASIC implementation of a program to calculate character separation indices is presented.

Biometry↗
PubMed2002

Sensory evaluation of character impact components in an apple model mixture.

Food aromas generally are complex mixtures of volatiles. In the present study, we investigated the joint effects of hexyl acetate, trans-2-hexenal and 1-hexanol on the multi-attribute perception of an apple aroma. The first two substances were identified earlier as positive contributors to the apple aroma (high character impact), whereas the third component was identified as an irrelevant or negative contributor (low character impact). Aroma quality was quantified using a set of eight graphic rating scales. All three components had significant effects on the aroma profiles. These effects consist mainly of an effect of each component on the attribute that described its individual character and an effect of all three components on ratings on the main character attribute 'apple'. As expected, the high impact components increased 'apple' ratings, whereas the low character impact component decreased 'apple' ratings. Furthermore, intensity ratings on the attribute that corresponded with the odour of the low impact component were suppressed by the presence of high impact components. These results indicate that the contributions of odorants to the mixture's aroma are not linear combinations of separate odour intensities, because sensory interactions were observed. In addition, humans detect components in complex mixtures more accurately than studies on identification performance have suggested. We conclude that for an adequate assessment of the effects of multiple mixture components on changes in aroma perception, it is sufficient to employ multiple response scales measuring intensities of attributes that are distinctive with respect to the expected qualitative changes. Results of this approach should be subjected to multivariate methods of statistical analysis.

Acetates↗
PubMedDate not supplied

Genetic analysis of fluctuating asymmetry for skeletal characters in mice.

Fluctuating asymmetry (FA)--nondirectional variation between left and right sides of bilateral characters--has become increasingly used as a measure of developmental stability. In the comparison of stability levels among various populations, however, it often has been assumed that FA does not have a genetic basis (i.e., its heritability is zero). To test this hypothesis, heritabilities were estimated via maximum likelihood correlations of parents and offspring for FA in eight quasi-continuous skeletal characters (primarily presence/absence of various foramina) in randombred house mice. Genetic correlations between left and right sides for each of the characters also were calculated to test whether they were one, as would be predicted if differences between sides are purely environmental in origin. Heritabilities of FA in all eight characters were not significantly different from zero, as hypothesized, their mean value being very low (0.032). Similarly, genetic correlations between sides were not significantly different from one for most of the characters. It was concluded that for this specific population of mice, there was no detectable additive genetic variance for FA.

Animals↗
PubMed1996

Conflicting character distribution within different data sets on cardueline finches: artifact or history?

Cardueline finches (Passeriformes: Fringillidae, Carduelinae) provide an example of unresolved species relationships despite decades of extensive study of the group. Existing morphological studies suffer from numerous cases of assumed parallel evolution due to a conflicting character distribution in different lineages. In this study, results of assumed parallel evolution due to a conflicting character distribution in different lineages. In this study, results of cytochrome b sequence analysis are compared with species relationships suggested by morphological and behavioral evidence. In the molecular analyses, species clusters mutually excluding each other were observed, lowering the statistical support of the internodes, i.e., the branches could not be resolved convincingly. Despite these difficulties, some phylogenetic signal was present in the molecular data as well as in the other approaches. In particular, any species or genus relationship suggested by cytochrome b sequence analysis was reflected by some other evidence. Based on this general congruence of the different data sets and on a considerable cytochrome b tree stability observed independent of species combination, choice of outgroup and tree-generating method, the short internodes are interpreted to reflect a historical reality. A model of cardueline evolution is proposed which assumes a population of cardueline ancestors with considerable polymorphism concerning the mitochondrial DNA and morphological characters alike. Retention of ancestral character states in different lineages and a subsequent rapid radiation are suggested to explain the conflicting character distributions observed in different fields of investigation.

Amino Acid Sequence↗
PubMed1996

Character congruence and phylogenetic signal in molecular and morphological data sets: a case study in the living Iguanas (Squamata, Iguanidae).

The lizard family Iguanidae comprises eight living genera distributed throughout the New and Old World, and includes several island endemics. We reconstruct phylogenetic relationships among these genera using 90 previously published morphological characters, to which we add a molecular (mtDNA sequence) data set that includes 742 nucleotides of the ND4 gene and the complete sequences of the histidine, serine, and leucine tRNAs (217 nucleotides). Trees were initially constructed separately from these three data sets, and then tested for significant conflict in topologies that would suggest the influence of different evolutionary processes. The three data sets were then combined, and a single tree was obtained from the total evidence that permitted identification of potential sources of character incongruence. Several additional analyses of the combined data sets were repeated with sequential deletion of successive classes of homoplastic characters, and we show that the same single tree topology is recovered in most cases. However, part of the tree structure collapses when the matrix of combined characters is completely purged of all homoplastic characters. We argue that this extreme results in an unacceptable loss of phylogenetic information, and we present a single phylogenetic hypothesis for all living genera of iguanas. We show that this hypothesis is significantly more parsimonious than either of two previously published trees, and we discuss the evolution and biogeography of the Iguanidae based on the preferred hypothesis.

Animals↗
PubMed1986

Effects of video display character size, clarity, and color on P-300 latency.

The P-300 is a positive polarity electroencephalographic (EEG) signal occurring about 300 ms after a surprising, novel, or unique stimulus. The amplitude of the P-300 is dependent on the degree of attention and importance the subject has assigned to the stimulus and on its relative novelty. P-300 latency is dependent on the time it takes the subject to mentally process the stimulus and determine if the information it carries is novel. In Experiment I, the latencies of P-300's for 40 and 80 column size video display characters were compared. The effect of dioptric blur (mean add power +2.44 D) on latency was also determined. It was found that 40 column size characters could be interpreted more quickly than 80 column size characters and that blur increased the processing time equally for both character sizes. In Experiment II, P-300 latencies for green and amber display screens were compared. Display screen color did not significantly affect latency, neither did the addition of lens powers ranging from a mean of -1.15 D to a mean of +1.15 D over the subjects' habitual lenses. However, it was found that latencies significantly increased when a mean add of +2.29 D for the green display or a mean add of +2.57 D for the amber display were used. (Chromatic aberration accounted for the difference in lens power for the green vs. amber display.) These results demonstrate that character size and clarity are significant factors in determining the time required to mentally process a stimulus. They also demonstrate that there is no clear advantage to using an amber vs. a green screen when speed of mental processing (as measured by P-300 latency) is used as a criterion.

Adult↗
PubMed2006

Dissociated roles of the middle frontal gyri in the processing of Chinese characters.

The present study examined a hypothesis that the right middle frontal gyrus participates in processing orthography of Chinese characters, while the left middle frontal gyrus mediates access to phonology and semantics. Brain activation during three character tasks, which required processing orthography, phonology, or semantics of Chinese characters, respectively, was measured by functional magnetic resonance imaging. Comparable neural activity in the right middle frontal gyrus was observed in all three character tasks that always demand orthographical processing. In contrast, the left middle frontal gyrus showed greater activation in the phonological and semantic tasks than in the orthographic task. These results suggest that the right and left middle frontal gyrus have dissociable functions in achieving Chinese character recognition.

Adult↗
PubMed1986

No correlation exists between the conjugative transfer of the autotrophic character and that of plasmids in Nocardia opaca strains.

A new isolate of Nocardia opaca was obtained by enrichment culture for aerobic lithoautotrophic growth on CO2 and H2. This strain, MR22, is very similar to N. opaca MR11 (formerly 1b) in functioning as a donor for genetic information determining the ability to grow lithoautotrophically (Aut character) in matings with Aut- strains of N. opaca or closely related heterotrophic species. The strain contains a plasmid, pHG33 of about 110 kb. A mutant was isolated from strain MR22 which was plasmid-free, and had lost the Aut character, resistance to 50 microM-thallium salt and susceptibility to the nocardia-specific bacteriophage phi B1. As a recipient of the Aut character, this plasmid-free mutant was as well suited as plasmid-bearing Aut- strains of N. opaca. In matings with the mutant as recipient the frequency of Aut+ transconjugants per donor was 3 X 10(-4) with N. opaca MR11 (pHG31-a, Aut+, Tlr, Strs, phi B1s) and 2 X 10(-3) with N. opaca MR22 (pHG33, Aut+, Tlr, Strs, phi B1r) as donor. Phenotypic characterization of the transconjugants, which had been selected for the Aut marker, revealed that in many cases the Aut marker had been transferred without plasmid transfer. Furthermore, plasmid-free, Aut+ transconjugants functioned as donors for the Aut marker. Both plasmid-free and plasmid-bearing transconjugants transferred the Aut marker to the Aut- strains of N. opaca with a frequency which was one or two orders of magnitude higher than that of the wild-type strains. The plasmids pHG31-a and pHG33 code for thallium resistance (50 microM-thallium acetate). The frequency of thallium-resistant transconjugants was 10(-1) to 10(-2) per donor; all thallium-resistant transconjugants contained the donor plasmid. We conclude that the plasmids pHG31-a of strain MR11 and pHG33 of strain MR22 of N. opaca carry the genetic information for thallium resistance but not the Aut character. As plasmid-free Aut+ strains can function as donors the Aut character is assumed to reside on the chromosome and to function as an independent self-transmissible genetic element.

Bacteriophages↗
PubMedDate not supplied

Personality and emotion-based high-level control of affective story characters.

Human emotional behavior, personality, and body language are the essential elements in the recognition of a believable synthetic story character. This paper presents an approach using story scripts and action descriptions in a form similar to the content description of storyboards to predict specific personality and emotional states. By adopting the Abridged Big Five Circumplex (AB5C) Model of personality from the study of psychology as a basis for a computational model, we construct a hierarchical fuzzy rule-based system to facilitate the personality and emotion control of the body language of a dynamic story character. The story character can consistently perform specific postures and gestures based on his/her personality type. Story designers can devise a story context in the form of our story interface which predictably motivates personality and emotion values to drive the appropriate movements of the story characters. Our system takes advantage of relevant knowledge described by psychologists and researchers of storytelling, nonverbal communication, and human movement. Our ultimate goal is to facilitate the high-level control of a synthetic character.

Affect↗
PubMed2000

Autonomy and the subjective character of experience.

In his famous paper, What Is It Like To Be a Bat?, Thomas Nagel argues against a reductive physicalist account of consciousness by highlighting what he calls "the subjective character of experience." In this paper I will argue that Nagel's insight is important for understanding the value placed on patient autonomy in medical ethics. Appreciation of the subjective character experience brings with it the necessity for an epistemological humility with respect to the lives of others and what can be said to be "right" for them. Appreciation of the subjective character of experience lies at the heart of empathy and our capacity to make decisions that genuinely reflect respect for the patient's autonomy. Through the example of a case involving extreme medical intervention, I identify some impediments to the proper recognition of autonomy. These kind of cases highlight the significance of affective responses with respect to the subjective character of experience, and, by extension, to our capacity to imagine and act in accordance with another's perspective. I argue that affective responses are appropriate and needed considerations in the case where one must attempt to assume another's perspective in order to respect autonomy. I conclude that understanding that experience has an irreducibly subjective character is essential to respecting patient autonomy.

Decision Making↗
PubMed2000

Neurobiological constraints and fly systematics: how different types of neural characters can contribute to a higher level dipteran phylogeny.

Much uncertainty still exists regarding higher level phylogenetic relationships in the insect order Diptera, and the need for independent analyses is apparent. In this paper, I present a parsimony analysis that is based on details of the nervous system of flies. Because neural characters have received little attention in modern phylogenetic analyses and the stability of neural traits has been debated, special emphasis is given to testing the robustness of the analysis itself and to evaluating how neurobiological constraints (such as levels of neural processing) influence the phylogenetic information content. The phylogenetic study is based on 14 species in three nematoceran and nine brachyceran families. All characters used in the analysis are based on anatomical details of the neural organization of the fly visual system. For the most part they relate to uniquely identifiable neurons, which are cells or cell types that can be confidently recognized as homologues among different species and thus compared. Parsimony analysis results in a phylogenetic hypothesis that favors specific previously suggested phylogenetic relationships and suggests alternatives regarding other placements. For example, several heterodactylan families (Bombyliidae, Asilidae, and Dolichopodidae) are supported in their placement as suggested by Sinclair et al. (1993), but Tipulidae and Syrphidae are placed differently. Tipulidae are placed at a derived rather than ancestral position within the Nematocera, and Syrphidae are placed within the Schizophora. The analysis suggests that neural characters generally maintain phylogenetic information well. However, by "forcing" neural characters onto conventional phylogenetic analyses it becomes apparent that not all neural centers maintain such information equally well. For example, neurons of the second-order visual neuropil, the medulla, contain stronger phylogenetic "signal" than do characters of the deeper visual center, the lobula plate. These differences may relate to different functional constraints in the two neuropils.

Animals↗
PubMed2000

Character displacement in polyphenic tadpoles.

Biologists have long known that closely related species are often phenotypically different where they occur together, but are indistinguishable where they occur alone. The causes of such character displacement are controversial, however. We used polyphenic spadefoot toad tadpoles (Spea bombifrons and S. multiplicata) to test the hypothesis that character displacement evolves to minimize competition for food. We also sought to evaluate the role of phenotypic plasticity in the mediation of competitive interactions between these species. Depending on their diet, individuals of both species develop into either a small-headed omnivore morph, which feeds mostly on detritus, or a large-headed carnivore morph, which specializes on shrimp. Laboratory experiments and surveys of natural ponds revealed that the two species were more dissimilar in their tendency to produce carnivores when they occurred together than when they occurred alone. This divergence in carnivore production was expressed as both character displacement (where S. multiplicata's propensity to produce carnivores was lower in sympatry than in allopatry) and as phenotypic plasticity (where S. multiplicata facultatively enhanced carnivore production in S. bombifrons, and S. bombifrons facultatively suppressed carnivore production in S. multiplicata). In separate experiments, we established that S. bombifrons (the species for which carnivore production was enhanced) was the superior competitor for shrimp. Conversely, S. multiplicata (the species for which carnivore production was suppressed and omnivore production enhanced) was the superior competitor for detritus. These results therefore demonstrate that selection to minimize competition for food can cause character displacement. They also suggest that both character displacement and phenotypic plasticity may mediate competitive interactions between species.

Animals↗
PubMed2001

Size and fluctuating asymmetry of morphometric characters in mice: their associations with inbreeding and t-haplotype.

Fluctuating asymmetry (FA), a ubiquitous type of asymmetry of bilateral characters, often has been used as a measure of developmental instability in populations. FA is expected to increase in populations subjected to genetic stressors such as inbreeding or environmental stressors such as toxins or parasites, although results have not always been consistent. We tested whether FA in four skeletal size characters and mandible shape was greater in a population of wild-derived mice reared in the laboratory and subjected to one generation of inbreeding (F = 0.25) versus that in an outbred group (F = 0.00). FA did not significantly differ between the inbred and outbred groups, despite the fact that these two groups differed dramatically in fitness under seminatural population conditions. As far as we know, this is the first study to evaluate the relationship between FA and inbreeding in wild house mice, and our general conclusion is opposite that of earlier work on laboratory inbred strains of mice and their hybrids. Size for two of the characters was significantly less in inbreds than in outbreds, however, and there was a significant difference between inbreds and outbreds in the signed differences of right and left sides in one character (humerus length). Some of the mice in both groups also were heterozygous or homozygous carriers of the t-complex. Because mice carrying this chromosome 17 variant are known to have reduced fitness, we also tested whether they had greater FA than mice carrying non-t-haplotypes. The overall level of a composite FA index calculated from all four characters was in fact significantly higher in the t-bearing mice. These combined results suggest that FA is not a generally sensitive proxy measure for fitness, but can be associated with fitness reductions for certain genetic stressors.

Analysis of Variance↗
PubMed2004

Three-year follow up of women with and without borderline personality disorder: development of Cloninger's character in adolescence.

The purpose of the present study was to examine the developmental patterns of Cloninger's biogenetic character traits in subjects with borderline personality disorder (BPD). Study subjects met Diagnostic and Statistical Manual of Mental Disorders (3rd edn, revised; DSM-III-R) criteria for BPD without comorbid axis I or II disorders, as determined by the Diagnostic Interview for Borderlines-Revised, Structured Clinical Interview for the DSM-III-R, and Diagnostic Interview for Personality Disorders. The BPD subjects and age- and sex-matched healthy comparison subjects were initially interviewed for Cloninger's biogenetic characters and re-interviewed at an interval of 1 year for the following 3 years. There were significant differences in the developmental patterns of self-directedness, cooperativeness, and self-transcendence between BPD and healthy comparison subjects (significant group by time interaction: repeated measures manova, F = 17.3, d.f. = 3,240, P < 0.001; F = 28.5, d.f. = 3,240, P < 0.001; F = 4.7, d.f. = 3,240, P < 0.01, respectively). The BPD subjects had less changes in character-related maturity with increasing age than did healthy comparison subjects. Post-hoc tests with Duncan's statistics revealed that subjects with BPD had significantly lower scores on self-directedness at all assessment time periods (P < 0.01) and lower scores on cooperativeness at the second-year and third-year follow-up assessments as compared to healthy comparison subjects (P < 0.01). The BPD subjects had a distinctively different developmental pattern of Cloninger's character compared to healthy comparison subjects. The character development of BPD patients was more fixed and immature than those of healthy comparison subjects.

Adolescent↗
PubMed1976

The pedophilic offender with antisocial character.

The purpose of the study was to clarify how pedophilic offenders with antisocial character (psychopathy) differ from "ordinary" pedophilic offenders, among whom there are many persons with immaturity and contact difficulties. For this purpose all pedophilia cases subjected to mental examination during a period of 25 years were investigated. Of these 81 cases, 38 could be regarded as antisocial characters on the basis of the current diagnostic criteria. The others were regarded as controls. The criminals with antisocial character had also been involved in other kinds of crimes and had had hyperactivity problems more often than controls. The controls were often immature, had a low intelligence, and were less able to have relations with adult people than were antisocial characters. However, according to the present results, these features might also make criminals with antisocial character more susceptible to pedophilia.

Adult↗
PubMed2001

Skewed distribution of morphological character scores and molecular markers in three interspecific crosses in Rosa section Caninae.

The dogroses, Rosa section Caninae, are all polyploid and characterised by their unbalanced meiosis; the pollen parent contributes one genome, whereas the seed parent contributes 3-5 genomes depending upon ploidy level of the species. As a result, genetically determined traits are expected to be matroclinally inherited. In the present study, the transmittal of genetic material was studied using manually scored reproductive characters (ovary and sepals), automated image analysis of leaflet shape (Fourier coefficients), and molecular markers (RAPD). The plant material consisted of a pair of reciprocal crosses between R. sherardii and R. villosa, a R. rubiginosa x R. sherardii cross and offspring obtained from selfing or within-population crosses of the parental species. All but one of the maternal markers were transmitted to all the offspring plants, whereas only 41% of the paternal markers were transmitted to all of them, 23% were never transmitted and 36% reached only one or two of the offspring plants. Canonical variates analyses (CVA) based on the vegetative characters could easily separate the offspring groups representing parental species and also all three hybridogenous offspring groups from each other, whereas CVA based on reproductive characters failed to separate R. sherardii x R. villosa from its seed parent, but otherwise distinguished all offspring groups. The study shows that the expression of characters as well as molecular marker inheritance is dependent upon the direction of the cross, and on the species involved. It also demonstrates the importance of employing several different types of character sets for an improved comprehension of the effects of the peculiar canina meiosis.

Chromosomes↗
PubMed2001

A recurrent neural network for partitioning of hand drawn characters into strokes of different orientations.

A neural network is described which is intended to extract orientation features that should be used for recognition of hand drawn characters. The network partitions the input hand drawn characters into separate line segments (strokes) according to their orientations. The network consists of several neural layers; each layer serves for extracting strokes of a certain orientation. Every neural layer has one-to-one correspondence with an input screen. The network uses an iterative update procedure which includes interactions of neurons inside each layer through oriented excitatory connections and inhibitory interrelations between the corresponding neurons of different layers. Computer simulation of the network was performed. Experiments showed that the network efficiently classifies all pixels of any hand drawn characters according to the orientations of the strokes constituting these characters and performs, as a result of that, a reasonable segmentation of characters.

Algorithms↗