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[reaction: see text] A new Kekulé polycyclic hydrocarbon with a singlet biradical index of 50% was synthesized. The singlet biradical character was assessed with UV and 1H-NMR spectroscopy, cyclic voltammetry, SQUID magnetic susceptibility measurement, and quantum chemical calculations.
Five genetically distinct and reproductively isolated species have been detected previously within the morphospecies Pseudoterranova decipiens from the Arctic-Boreal, Boreal and Antarctic. Morphological analysis was carried out on male specimens identified by genetic (allozyme) markers, allowing the detection of significant differences at a number of characters between two members of the P. decipiens complex, namely P. decipiens A and B. On the basis of such differences, the nomenclatural designation for the two species is discussed. The names Pseudoterranova krabbei n. sp. and P. decipiens (sensu stricto) are proposed for species A and B, respectively. Morphological and genetic differentiation between the two species is shown using multivariate analysis. Allozyme diagnostic keys for routine identification of the four members of the P. decipiens complex, namely P. decipiens (s.s.), P. krabbei, P. bulbosa and P. azarasi, irrespective of sex and life-history stage, are provided.
A theoretical model is presented to study the stepwise thermal unfolding of globular proteins using the stabilizing/destabilizing characters of amino acid residues in protein crystals. A multiple regression relation connecting the melting temperature and the amounts of stabilizing and destabilizing groups of residues in a protein, when used for the thermal behavior of peptide segments, provides reliable results on the stepwise unfolding nature of the protein. In ribonuclease A, the shell residues 16-22 are predicted to unfold earlier in the temperature range 30-45 degrees C; the beta-sheet structures undergo thermal denaturation as a single cooperative unit and there is evidence indicating the segment 106-118 as a nucleation site. In ribonuclease S, the S-peptide unfolds earlier than S-protein. The predicted average and the range of melting temperatures, and the folding pathways of a set of globular proteins, agree very well with the experimental results. The results obtained in the present study indicate that (i) most of the nucleation parts possess high relative thermal stability, (ii) the unfolded state retains some residual structure, and (iii) some segments undergo gradual and overlapping thermal denaturation.
Our objective was to test the hypothesis that the pheromone blend and/or diel periodicity of pheromonal communication differ in populations of the nun moth, Lymantria monacha (Lepidoptera: Lymantriidae), from eastern Asia (northern Honshu, Japan) and Central Europe (Bohemia, Czech Republic). Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses of pheromone gland extract of female L. monacha from Japan confirmed the presence of compounds previously identified in pheromone extracts of L. monacha from Bohemia, as follows: (Z)-7-octadecene, 2-methyl-(Z)-7-octadecene (2me-Z7-18Hy), cis-7,8-epoxy-octadecane (monachalure), and cis-7,8-epoxy-2-methyloctadecane (disparlure). Field experiments in Honshu suggested that (+)-monachalure is the major pheromone component of L. monacha. 2me-Z7-18Hy significantly enhanced attractiveness of (+)-monachalure. Addition of (+)-disparlure to (+)-monachalure plus 2me-Z7-18Hy in Honshu and Bohemia increased attractiveness of lures by 1.2 and 20 times, respectively, indicating that (+)-disparlure is of least and most significance in the respective L. monacha populations. Moreover, capture of male L. monacha in pheromone-baited traps between 18:00 and 24:00 hr in Bohemia and 2:00 and 5:00 hr in Honshu revealed a markedly different diel periodicity of pheromonal communication. Pheromonal communication late at night and use of (+)-monachalure, rather than (+)-disparlure, as the major pheromone component by L. monacha in Honshu may have resulted from interspecific competition with coseasonal L. fumida, which uses the early night for pheromonal communication and (+)-disparlure as major pheromone component. Whether communication channel divergence of L. monacha in Honshu indeed constitutes a case of reproductive character displacement is difficult to prove. The evolution of such divergence in sympatric populations of L. fumida and L. monacha would have to be demonstrated.
Gordionus violaceus (Baird, 1853) and G. wolterstorffii (Camerano, 1888) are regarded as two species which are clearly separated by distinct cuticular patterns. A study of 59 specimens of these two species from Britain and Ireland revealed numerous transitional stages between the cuticular patterns that are regarded as being typical for each species. Variation was also found at the posterior end, but no character separates both species. Therefore, G. violaceus and G. wolterstorffii might represent one polymorphic species. Four specimens resembled G. violaceus but had a different cuticular pattern, including a second type of areole occurring in a pattern which has been named a megareolar pattern. This might represent a separate species, but a detailed determination relies upon further revisional work in the genera Gordionus, Parachordodes and Paragordionus.
Variability of the haptoral hard parts of four Black Sea Gyrodactylus species (G. alviga Dmitrieva & Gerasev, 2000; G. crenilabri Zaika, 1966; G. flesi Malmberg, 1957; G. sphinx Dmitrieva & Gerasev, 2000) was studied in relation to season, host and geographical variability. A discriminant analysis was carried out on the measurements of 14 characters of the haptor of all four species. The haptoral hard parts of the investigated gyrodactylids decrease in size with an increase in water temperature. It is known that life-span of gyrodactylids is negatively correlated with water temperature and they exhibit peak intensities at low temperature. At the same time, life-span is considered to be a general indicator of a favourable environment. Therefore, high water temperature is not apparently advantageous for gyrodactylids. In the case of low marine salinity, in adapted species the sizes of the haptoral hard parts are larger at lower levels of salinity and vice versa for typical marine species. Lastly, in specimens parasitising the primary host, these features are larger than in those parasitising a secondary host. It is possible to say that, in general, the more favourable the environment for gyrodactylids the larger their haptoral hard parts. Unfavourable environmental conditions reduce the time of embryogenesis, which has a dual effect on gyrodactylids: positive in relation to their reproduction (by increasing the reproduction rate) and negative in relation to their development (by decreasing the size of the haptoral hard parts).
A collection of 64 fig (Ficus carica L.) accessions was characterized through the use of RAPD markers, and results were evaluated in conjunction with morphological and agronomical characters, in order to determine the genetic relatedness of genotypes with diverse geographic origin. The results indicate that fig cultivars have a rather narrow genetic base. Nevertheless, RAPD markers could detect enough polymorphism to differentiate even closely related genotypes (i.e., clones of the same cultivar) and a unique fingerprint for each of the genotypes studied was obtained. No wasteful duplications were found in the collection. Cluster analysis allowed the identification of groups in accordance with geographic origin, phenotypic data and pedigree. Taking into account the limited information concerning fig cultivar development, the results of this study, which provide information on the genetic relationships of genetically distinct material, dramatically increase the fundamental and practical value of the collection and represent an invaluable tool for fig germplasm management.
The influence of personality factors on the appraisal of subjective quality of life in individuals with schizophrenia or schizoaffective disorder is not much investigated. The present study examined this relationship in a sample of 104 patients living in the community. The temperament and character inventory was used to assess personality and the Lancashire quality of life profile was used to assess quality of life. The results showed that lower levels of harm avoidance and higher levels of self-directedness were significantly correlated to a better subjective quality of life. Regression analyses controlling for psychopathology revealed that a higher level of self-directedness was significantly associated with a better subjective quality in all aspects measured and explained the variance in the latter in the range of 4-12%. It is concluded that personality factors are involved in severely mentally ill individuals' assessment of their quality of life and should be accounted for in evaluations of quality of life assessments. The strength and directions of this influence require further studies.
Escherichia coli K12 containing the transposon Tn5044 mer operon (merR, T, P, C, and A genes) is resistant to mercuric chloride at 30 degrees C but sensitive to this compound at 37-41.5 degrees C. We have studied the mechanism underlying the temperature-sensitive nature of this mercury resistance phenotype, and found that the expression of the Tn5044 merA gene coding for mercuric reductase (MerA) is severely inhibited at non-permissive temperatures. Additionally, MerA showed a considerably reduced functional activity in vivo at non-permissive temperatures. However, the temperature-sensitive character of the functioning of this enzyme in cell extracts, where it interacted with one of the low-molecular weight SH compounds rather than with the transport protein MerT (as is the case in vivo), was not apparent. These data suggest that the temperature-sensitive mercury resistance phenotype should stay under control at two stages: when the merA gene is expressed and when its product interacts with MerT to accept the mercuric ion.
Due to the extreme states of masochism, dependency, and narcissistic rage that these patients experience, the treatment must be attuned to the inevitable periods of regression and primitive defense. The patient feels compelled to be a servant to the object, yet is furious at this less than equal status. The alternating states of idealizing the object in a masochistic fashion, the anger at the lack of self importance, and the desperate hope for soothing from that object create an externally focused character structure, which generally leads to a pattern of acting out, the lack of internal linking processes, and a scarcity of interpersonal skills that foster mutuality. A fundamental lack of self soothing leads to a perpetual search and craving for the soothing talents of the object. It is often unconsciously believed that compliance and servitude will bring about this gift of soothing from the object. Hans Loewald (1962) had described internalization as a process whereby the child reaches out to take back from the environment what has been removed from him in an ever-increasing manner since his birth. For the forgotten hero, this theory is definitely true. Not only is the treatment of this type of patient one of gradual internalization of new internal object relationships and the working through of the older more pathological ones, but it is a true understanding between patient and analyst of the original nontolerable removal of the uniqueness of the self via reality and/or fantasy states. When this situation is focused upon and worked with, the taking back from the environment can occur in a spirit devoid of former states of envy, hate, resentment, and wild craving that were formally protected and disguised in a facade of dependent masochism. The patient has essentially experienced or perceived his parents, usually the mother, as not providing a soothing function or a proper fit for his developing ego. The patient has then gone about constructing various methods to compensate for this lack. The analyst is often experienced as not providing an adequate soothing function, but this emptiness is warded off from conscious expression with a compromise formation of dependent, masochistic, or narcissistic methods of relating. This style of compromise hides any envy, hunger, or rage and keeps alive the hopes of being rewarded with soothing. The patients expects to be used as a waste disposal unit and believes that this dumping by the object into him is the longed-for love. Ideally, interpretations focus upon the hunger for the soothing function of the object and the drive to obtain it at any cost. The patient will fiercely resist because he believes that in giving up his masochism and dependency, he would expose his envy and narcissistic injury. This patient believes he would then lose any hope of ever receiving the soothing function due to the fantasized destruction of the source of that soothing, his beloved object.
Neuroglycan C (NGC), a brain-specific transmembrane proteoglycan, is thought to bear not only chondroitin sulfate but also N- and O-linked oligosaccharides on its core protein. In this study, we isolated and purified NGC from rat brains at various developmental stages by immunoaffinity column chromatography or by immunoprecipitation, and examined the structural characters of its carbohydrate moiety. The chondroitin sulfate disaccharide composition of NGC at postnatal day 10 was significantly different from those of two secreted chondroitin sulfate proteoglycans, neurocan and phosphacan, purified from the brain at the same developmental stage; higher levels of 4-sulfate unit and E unit, a disulfated disaccharide unit, and a lower level of 6-sulfate unit. The levels of both 6-sulfate and E units decreased with a compensatory increase of 4-sulfate unit with postnatal development of the brain. Lectin-blot analysis of the NGC core glycoprotein prepared by chondroitinase digestion confirmed that NGC actually bore both N- and O-linked carbohydrates, and also revealed that lectin-species reactive with NGC did not always recognize other brain-specific proteoglycans, neurocan and phosphacan, and vice versa, even though they were isolated from the brain at the same stage. The reactivity of NGC with lectins and with the HNK-1 antibody markedly changed as the brain matured. These findings indicate that the structure of the carbohydrate moiety of NGC is developmentally regulated, and differs from those of neurocan and phosphacan. The developmentally-regulated structural change of the carbohydrates on NGC may be partly implicated in the modulation of neuronal cell recognition during brain development.
OBJECTIVE: To determine the influence of language and culture on the temperament and character (TCI) measure in a Chinese sample. METHOD: We translated the TCI into Mandarin and had a non-psychiatric sample of Malaysian Chinese subjects complete the TCI at baseline and at a 1-month retest, with subsets completing English or Mandarin versions alternatively or on both occasions. Analyses examine the TCI factor structure and any impact of language and culture on TCI scoring. RESULTS: We identified age, gender, occupation and language effects on TCI scale scores. Test-retest reliability was high and not compromised by language. Scale internal consistency was also high. Factor analyses of separate sets of TCI scales corresponded strongly to the structure identified in the TCI development studies. CONCLUSION: The results indicate that TCI is likely to have applicability to Chinese subjects, and argue against properties being constrained by the English language or by western culture.
The authors evaluated the relationship between P. T. Costa and R. R. McCrae's (1992) NEO 5-factor model, C. R. Cloninger's (1993) 7-factor Temperament and Character Inventory (TCI), and the American Psychiatric Association's (1994) Diagnostic and Statistical Manual of Mental Disorders, 4th ed., personality disorders in 370 inpatient and outpatient alcohol, cocaine, and opiate abusers. NEO Neuroticism was associated with many disorders, and different patterns for Agreeableness, Conscientiousness, and Extraversion emerged for the different disorders. Several TCI scales were associated with different personality disorders, although not as strongly as the NEO dimensions. Results did not support most predictions made for the TCI. Normal personality dimensions contributed significantly to the prediction of personality disorder severity above and beyond substance abuse and depression symptoms.
The authors tested a dolphin's (Tursiops truncatus) understanding of human manual pointing gestures to 3 distal objects located to the left of, to the right of, or behind the dolphin. The human referred to an object through a direct point (Pd), a cross-body point (Px), or a familiar symbolic gesture (S). In Experiment 1, the dolphin responded correctly to 80% of Pds toward laterally placed objects but to only 40% of Pds to the object behind. Responding to objects behind improved to 88% in Experiment 2 after exaggerated pointing was briefly instituted. Spontaneous comprehension of Pxs also was demonstrated. In Experiment 3, the human produced a sequence of 2 Pds, 2 Pxs, 2 Ss, or all 2-way combinations of these 3 to direct the dolphin to take the object referenced second to the object referenced first. Accuracy ranged from 68% to 77% correct (chance = 17%). These results established that the dolphin understood the referential character of the human manual pointing gesture.
This article examines the cultural context of early American personality psychology through a consideration of the early career of Gordon Allport. Between 1921 and 1937, Allport was among the leading figures in the movement to establish personality as a research category in American psychology. Far from being a strictly scientific concern, Allport's project was deeply embedded in the cultural politics of the age. Of particular importance was the gradual erosion of the language of character and the self-sacrificing, morally grounded self that it supported. Allport's "psychology of personality" helped fuel this trend while simultaneously attempting to resist it. His experience illustrates the elasticity and moral ambiguity of the newly emerging category of personality.
Developmental stability was assessed among lines of mice subjected to 11 generations of selection for increased (up line) and decreased (down line) widths of the first maxillary molar (M1), primarily to test the hypothesis that this stability would decline over time as a result of selection. Fluctuating asymmetry (FA) was used as an inverse measure of developmental stability, and was calculated for the M1 and a correlated character, the second mandibular molar (M2), in each generation. As measured by the regression of FA on generations, there was a statistically significant decline in stability only in the down selection line for the M2, and this trend did not differ significantly from that for the control line. The combined regressions obtained from pooling over all three lines were significantly different from zero in both molars, however, and this was taken to be evidence of a decline in stability due to increased homozygosity presumably generated by inbreeding during the selection experiment. The variation in FA among generations was greater for the selection lines than the control line for both molars, especially for the M2. The heritability of the M1 (and M2) was high, but there was no significant additive genetic variance for FA in either molar.
Using a new and more general genetic model called the discrete-allelic state model and assuming discrete-time process, the evolutionary changes of genetic variation of quantitative characters, controlled by a few loci, within and between populations during the process of genetic differentiation of populations or species, are studied under the effects of mutation and centripetal selection in infinitely large populations. While in a finite population and ignoring selection, the rate of change of additive genetic variance depends on mutation and effective population size, traits under optimal selection in infinitely large populations go through the dynamics of a rather complicated form depending on the relative intensities of selection and mutation. When a population, which has reached steady-state by mutation-selection balance, splits into two, in one of which the same optimum genotype holds but in the other the optimum shifts a few standard deviations away from the original optimum, the corresponding daughter population starts differentiating from its sister population by favouring certain class of mutant alleles and discarding others which were originally favoured. During this process of turn over of genes, both the intra- and inter-populational variances undergo a complicated change, and the ratio of the former to the latter is a non-linear function of time of divergence. This pattern is qualitatively very different from the case when selection is absent. The intra-population distribution of genotypic values, during this transition, is shown to deviate considerably from normality. The presence of linkage seems to retard the accumulation of intra-populational genetic variance. The implications of these results are discussed in comparison with the earlier findings of evolutionary models of quantitative traits.
Ricklefs claims to show that morphological evolution in birds is associated with speciation events--that is, it is punctuational--by inference from data on only species number, clade age and character variance from a range of passerine clades. He suggests that variance increases in proportion with clade age under gradual change, but in proportion to the logarithm of species number if change is punctuational. Here I show that both clade age and the logarithm of species number independently predict variance under both gradual and punctuational change, rendering Ricklefs' results uninformative about his central hypothesis.