363 resultados para Congruence


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In most taxa, species boundaries are inferred based on differences in morphology or DNA sequences revealed by taxonomic or phylogenetic analyses. In crickets, acoustic mating signals or calling songs have species-specific structures and provide a third data set to infer species boundaries. We examined the concordance in species boundaries obtained using acoustic, morphological, and molecular data sets in the field cricket genus Itaropsis. This genus is currently described by only one valid species, Itaropsis tenella, with a broad distribution in western peninsular India and Sri Lanka. Calling songs of males sampled from four sites in peninsular India exhibited significant differences in a number of call features, suggesting the existence of multiple species. Cluster analysis of the acoustic data, molecular phylogenetic analyses, and phylogenetic analyses combining all data sets suggested the existence of three clades. Whatever the differences in calling signals, no full congruence was obtained between all the data sets, even though the resultant lineages were largely concordant with the acoustic clusters. The genus Itaropsis could thus be represented by three morphologically cryptic incipient species in peninsular India; their distributions are congruent with usual patterns of endemism in the Western Ghats, India. Song evolution is analysed through the divergence in syllable period, syllable and call duration, and dominant frequency.

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Studies on the diffusion of methane in a zeolite structure type LTA (as per IZA nomenclature) have indicated that different types of methane zeolite potentials exist in the literature in which methane is treated within the united-atom model. One set of potentials, referred to as model A, has a methane oxygen diameter of 3.14 angstrom, while another set of potential parameters, model B, employs a larger value of 3.46 angstrom. Fritzsche and co-workers (1993) have shown that these two potentials lead to two distinctly different energetic barriers for the passage of methane through the eight-ring window in the cation-free form of zeolite A. Here, we compute the variation of the self-diffusivity (D) with loading (c) for these two types of potentials and show that this slight variation in the diameter changes the concentration dependence qualitatively: thus, D decreases monotonically with c for model A, while D increases and goes through a maximum before finally decreasing for model B. This effect and the surprising congruence of the diffusion coefficients for both models at high loadings is examined in detail at the molecular level. Simulations for different temperatures reveal the Arrhenius behaviour of the self-diffusion coefficient. The apparent activation energy is found to vary with the loading. We conclude that beside the cage-to-cage jumps, which are essential for the migration of the guest molecules, at high concentrations migration within the cage and guest guest interactions with other molecules become increasingly dominant influences on the diffusion coefficient and make the guest zeolite interaction less important for both model A and model B.

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How the brain converts parallel representations of movement goals into sequential movements is not known. We tested the role of basal ganglia (BG) in the temporal control of movement sequences by a convergent approach involving inactivation of the BG by muscimol injections into the caudate nucleus of monkeys and assessing behavior of Parkinson's disease patients, performing a modified double-step saccade task. We tested a critical prediction of a class of competitive queuing models that explains serial behavior as the outcome of a selection of concurrently activated goals. In congruence with these models, we found that inactivation or impairment of the BG unmasked the parallel nature of goal representations such that a significantly greater extent of averaged saccades, curved saccades, and saccade sequence errors were observed. These results suggest that the BG perform a form of competitive queuing, holding the second movement plan in abeyance while the first movement is being executed, allowing the proper temporal control of movement sequences.

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Let Gamma subset of SL2(Z) be a principal congruence subgroup. For each sigma is an element of SL2(Z), we introduce the collection A(sigma)(Gamma) of modular Hecke operators twisted by sigma. Then, A(sigma)(Gamma) is a right A(Gamma)-module, where A(Gamma) is the modular Hecke algebra introduced by Connes and Moscovici. Using the action of a Hopf algebra h(0) on A(sigma)(Gamma), we define reduced Rankin-Cohen brackets on A(sigma)(Gamma). Moreover A(sigma)(Gamma) carries an action of H 1, where H 1 is the Hopf algebra of foliations of codimension 1. Finally, we consider operators between the levels A(sigma)(Gamma), sigma is an element of SL2(Z). We show that the action of these operators can be expressed in terms of a Hopf algebra h(Z).

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Proteolytic enzymes have evolved several mechanisms to cleave peptide bonds. These distinct types have been systematically categorized in the MEROPS database. While a BLAST search on these proteases identifies homologous proteins, sequence alignment methods often fail to identify relationships arising from convergent evolution, exon shuffling, and modular reuse of catalytic units. We have previously established a computational method to detect functions in proteins based on the spatial and electrostatic properties of the catalytic residues (CLASP). CLASP identified a promiscuous serine protease scaffold in alkaline phosphatases (AP) and a scaffold recognizing a beta-lactam (imipenem) in a cold-active Vibrio AP. Subsequently, we defined a methodology to quantify promiscuous activities in a wide range of proteins. Here, we assemble a module which encapsulates the multifarious motifs used by protease families listed in the MEROPS database. Since APs and proteases are an integral component of outer membrane vesicles (OMV), we sought to query other OMV proteins, like phospholipase C (PLC), using this search module. Our analysis indicated that phosphoinositide-specific PLC from Bacillus cereus is a serine protease. This was validated by protease assays, mass spectrometry and by inhibition of the native phospholipase activity of PI-PLC by the well-known serine protease inhibitor AEBSF (IC50 = 0.018 mM). Edman degradation analysis linked the specificity of the protease activity to a proline in the amino terminal, suggesting that the PI-PLC is a prolyl peptidase. Thus, we propose a computational method of extending protein families based on the spatial and electrostatic congruence of active site residues.

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Papillomaviruses (PVs) are widespread pathogens. However, the extent of PV infections in bats remains largely unknown. This work represents the first comprehensive study of PVs in Iberian bats. We identified four novel PVs in the mucosa of free-ranging Eptesicus serotinus (EserPV1, EserPV2, and EserPV3) and Rhinolophus ferrumequinum (RferPV1) individuals and analyzed their phylogenetic relationships within the viral family. We further assessed their prevalence in different populations of E. serotinus and its close relative E. isabellinus. Although it is frequent to read that PVs co-evolve with their host, that PVs are highly species-specific, and that PVs do not usually recombine, our results suggest otherwise. First, strict virus-host co-evolution is rejected by the existence of five, distantly related bat PV lineages and by the lack of congruence between bats and bat PVs phylogenies. Second, the ability of EserPV2 and EserPV3 to infect two different bat species (E. serotinus and E. isabellinus) argues against strict host specificity. Finally, the description of a second noncoding region in the RferPV1 genome reinforces the view of an increased susceptibility to recombination in the E2-L2 genomic region. These findings prompt the question of whether the prevailing paradigms regarding PVs evolution should be reconsidered.

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Vários estudos encontraram maiores taxas de mortalidade por batidas no trânsito entre homens do que entre mulheres e entre homens jovens do que entre homens mais velhos. No entanto, há uma lacuna quanto a explicações para essas diferenças. Esse estudo, diferentemente dos antecessores, parte de hipóteses postuladas a priori, sobre como devem variar as taxas de mortalidade por batidas no trânsito, de acordo com sexo e idade. Espera-se encontrar a presença e ausência de certas associações e interações, com base na teoria moderna da seleção sexual aplicada ao estudo do comportamento humano, especificamente, a síndrome do macho jovem. O objetivo do presente estudo é comparar tendências nas taxas de mortalidade por batida de carro e moto segundo sexo e idade. Trata-se de um estudo ecológico com Estado como unidade geográfica de análise e o ano calendário como unidade temporal de análise. A população do estudo foi composta por homens e mulheres de 18 a 60 anos residentes no Estado do Rio de Janeiro, entre 2004 e 2010, e no Estado do Rio Grande do Sul, entre os anos de 2001 e 2010. Os resultados mostraram que o número de mortes por batida de carro e de moto, considerando o número de habilitados para guiar tais veículos, foi maior em homens do que em mulheres e em indivíduos mais jovens do que mais velhos. Além dessa interessante congruência entre os resultados encontrados e as hipóteses postuladas, descobrimos uma intrigante exceção: no Estado do Rio de Janeiro, a taxa de mortalidade por batida de moto foi consideravelmente maior em mulheres do que em homens. As tendências nas taxas de mortalidade por batida de carro e moto no Estado do Rio de Janeiro vêm apresentando uma queda nos últimos anos. No Rio Grande do Sul, as taxas de mortalidade por batida de moto também vêm caindo ao longo dos anos, enquanto que as taxas de mortalidade por batida de carro vêm apresentando aumento. Tais resultados levam a concluir que a Síndrome do Macho Jovem parece ser uma potente e promissora teoria para ajudar a postular hipóteses sobre o risco de morte no trânsito.

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Mawsoniidae é uma família de actinístios fósseis, conhecidos popularmente como celacanto, sendo encontrados em paleoambientes continental e marinho. O táxon foi proposto na década de 1990, apresentando, a partir de então, alguns estudos abordando sua filogenia num contexto cladístico. Trata-se de um grupo monofilético, sendo representado por cinco gêneros inquestionáveis (i. e., Axelrodichthys, Chinlea, Diplurus, Mawsonia e Parnaibaia), além de outros dez que possuem alguma discordância na sistemática (i. e., Alcoveria, Garnbergia, Heptanema, Indocoelacanthus, Libys, Lualabaea, Megalocoelacanthus, Moenkopia, Rhipis e Trachymetopon). Cabe ressaltar que nem todos estes gêneros foram contemplados nas análises cladísticas de Mawsoniidae. Mawsoniidae possui considerável interesse biogeográfico, considerando sua extensa amplitude temporal (Triássico Médio ao Cretáceo Superior) e ampla distribuição geográfica (Américas do Sul e do Norte, África e Europa). Os gêneros restritos à América do Norte (Diplurus e Chinlea) e Europa (Alcoveria) possuem os registros mais antigos (Triássico Médio-Jurássico Inferior). Já os gêneros restritos ao Hemisfério Sul (Mawsonia, Axelrodichthys e Parnaibaia) distribuem-se do Jurássico Superior ao Cretáceo Superior, no Brasil e na África. A presente dissertação propôs analisar a Biogeografia Histórica de todos os gêneros (os válidos e os de posicionamento taxonômico controverso) de Mawsoniidae, aplicando o método panbiogeográfico de análise de traços. A partir desta análise, foram obtidos 11 traços individuais das espécies e três traços generalizados (TGs). O TG1, que foi denominado Newark Nordeste, ocorre nos estratos do Grupo Newark (Triássico Superior); o TG2, que foi denominado Centro-oeste gondwânico, ocorre na Formação Lualaba (Jurássico Superior); e o TG3, que foi denominado Itapecuru-Alcântara-Santana, ocorre nas formações Itapecuru-Alcântara-Santana (Cretáceo Inferior). Com base no padrão de distribuição encontrado, sugere-se que a origem do grupo ocorreu a partir do Triássico Médio/Superior na Pangeia Oriental, com subsequente expansão no Jurássico Inferior, corroborada por registros de Indocoelacanthus e Trachymetopon. A expansão do grupo em direção à Gondwana Ocidental ocorreu a partir do Cretáceo Inferior, com registros dos gêneros Mawsonia e Axelrodichthys. A análise panbiogeográfica também foi aplicada para produzir traços individuais para os gêneros em determinados períodos geológicos, os quais mostraram congruência com os traços individuais das espécies. Os resultados aqui obtidos reforçaram o potential do método panbiogeográfico na obtenção dos padrões de distribuição e, consequentemente, nas áreas de endemismo de Mawsoniidae, ao longo de todo o Mesozoico.

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Papillomaviruses (PVs) are widespread pathogens. However, the extent of PV infections in bats remains largely unknown. This work represents the first comprehensive study of PVs in Iberian bats. We identified four novel PVs in the mucosa of free-ranging Eptesicus serotinus (EserPV1, EserPV2, and EserPV3) and Rhinolophus ferrumequinum (RferPV1) individuals and analyzed their phylogenetic relationships within the viral family. We further assessed their prevalence in different populations of E. serotinus and its close relative E. isabellinus. Although it is frequent to read that PVs co-evolve with their host, that PVs are highly species-specific, and that PVs do not usually recombine, our results suggest otherwise. First, strict virus-host co-evolution is rejected by the existence of five, distantly related bat PV lineages and by the lack of congruence between bats and bat PVs phylogenies. Second, the ability of EserPV2 and EserPV3 to infect two different bat species (E. serotinus and E. isabellinus) argues against strict host specificity. Finally, the description of a second noncoding region in the RferPV1 genome reinforces the view of an increased susceptibility to recombination in the E2-L2 genomic region. These findings prompt the question of whether the prevailing paradigms regarding PVs evolution should be reconsidered.

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MOTIVATION: Synthetic lethal interactions represent pairs of genes whose individual mutations are not lethal, while the double mutation of both genes does incur lethality. Several studies have shown a correlation between functional similarity of genes and their distances in networks based on synthetic lethal interactions. However, there is a lack of algorithms for predicting gene function from synthetic lethality interaction networks. RESULTS: In this article, we present a novel technique called kernelROD for gene function prediction from synthetic lethal interaction networks based on kernel machines. We apply our novel algorithm to Gene Ontology functional annotation prediction in yeast. Our experiments show that our method leads to improved gene function prediction compared with state-of-the-art competitors and that combining genetic and congruence networks leads to a further improvement in prediction accuracy.

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A business model for integrating global-production efficiencies with sustainability is discussed. Two trends that emulate some of the aspects of the wealthy are the increasing willingness of many to pay extra for customization such as clothes, of kitchens and the increasing acceptance of purchasing a service as a product substitute. Two final trends that are also based in the attitudes of people is an increased awareness of the value of local culture and an increased concern with issues of sustainability. The results show that the goal congruence between for-profit and not-for-profit organizations puts emphasis on value and belief of the organization.

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Impedance inversion is very important in seismic technology. It is based on seismic profile. Good inversion result is derived from high quality seismic profile, which is formed using high resolution imaging resolution. High-resolution process demands that signal/noise ratio is high. It is very important for seismic inversion to improve signal/noise ratio. the main idea is that the physical parameter (wave impedance), which describes the stratigraphy directly, is achieved from seismic data expressing structural style indirectly. The solution of impedance inversion technology, which is based on convolution model, is arbitrary. It is a good way to apply the priori information as the restricted condition in inversion. An updated impedance inversion technology is presented which overcome the flaw of traditional model and highlight the influence of structure. Considering impedance inversion restricted by sedimentary model, layer filling style and congruence relation, the impedance model is built. So the impedance inversion restricted by geological rule could be realized. there are some innovations in this dissertation: 1. The best migration aperture is achieved from the included angle of time surface of diffracted wave and reflected wave. Restricted by structural model, the dip of time surface of reflected wave and diffracted wave is given. 2. The conventional method of FXY forcasting noise is updated, and the signal/noise ratio is improved. 3. Considering the characteristic of probability distribution of seismic data and geological events fully, an object function is constructed using the theory of Bayes estimation as the criterion. The mathematics is used here to describe the content of practice theory. 4. Considering the influence of structure, the seismic profile is interpreted to build the model of structure. A series of structure model is built. So as the impedance model. The high frequency of inversion is controlled by the geological rule. 5. Conjugate gradient method is selected to improve resolving process for it fit the demands of geophysics, and the efficiency of algorithm is enhanced. As the geological information is used fully, the result of impedance inversion is reasonable and complex reservoir could be forecasted further perfectly.

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Job Burnout has been a focus of the Occupational Stress Research. As a typical,helping occupation, teacher has attracted widely attention and researches in the areas of pedagogy and psychology. The special subgroup of teacher, headmasters who are the elites of the Basic Education, is ignored. The research about principals’ Job Burnout is nearly blank after analyzing related documents and information. With the development of the society, people pay more and more attention to the education and put more demands on the headmasters, especially middle-school principals. They are required not only to be good educators, who are equipped with all the inner qualities as a teacher, but also good managers. So the main purpose of this research was to compare the principal group with ordinary teacher group, and reveal underling factors, such as background variables and psychological protection variables. A representative sample of Wenzhou middle school principals sized 192 and a sample of middle school teacher sized 302 were sampled from various schools. The educational version of burnout inventory, self consistency scale, and interpersonal trust scale were administrated to the two samples, together with some demographic variables of interest. The applicability and equivalence of the three instruments used in this study were checked. Based on well-established reliability and cross-sample congruence of measures, the difference between principals and teachers was test. Then the contributing factors were analysis gradually. The five background variables were examined one by one in the two samples separately. A multiple covariance analysis was conducted to test whether there remained any difference between these two samples on the variables of interest. Regression analysis was used to further control the effect of self harmony and interpersonal trust to test the difference between two samples. Mediating analysis was conducted to build the relationship among the three constructs. The main results of the research were stated as following: 1. The internal consistency coefficients of all the scales were good, and no difference exited between the two groups. The measurement equivalence of three instruments was established well. The measures could be applied to and comparing the two samples. 2. The self-harmony, and interpersonal trust of principals were better than the ordinary middle-school teachers. Job Burnout of principals was significant lower than teachers. 3. Demographic variables like the gender, age groups, income levels, disricts, and the type of school, were important influencing factors. The difference patterns of the variables on these five variables in two samples had similarity and distinction. 4. After controlling the background variables, there remained significant difference between principals and teachers on the variables of interest. 5. Job Burnout negatively correlated with self-harmony and interpersonal trust. That is to say,the lower the degree of self-harmony and interpersonal are, the serious of the Job Burnout is, The correlation between the self-harmony and the interpersonal trust was positive. 6. After statistically controlling the background variables and psychological variables, there still exited significant difference between two groups of this study. Also, self harmony and interpersonal trust were significant protection predictors to different aspect of job burnout. 7. Mediating analysis was conducted to the residual score of the three constructs after controlling the five variables and group membership. Self harmony partially mediated the relationship between interpersonal trust and job burnout. That is, interpersonal trust had indirect effect to burnout mediated by self harmony, also had direct effect to burnout.

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This study employed the compliance, identification, and internalization model of attitude change to explore the mechanism of rule-following behaviors in organizations. The objectives of this study were to examine the effects of individual utilitarianism and formalism on rule compliance, deference and rule-breaking behaviors, and the relationships between legitimacy, organizational identification, and value internalization. I surveyed 262 employees from a high-tech corporation in Beijing. After Confirmative Factor Analysis, Regression Analysis, and Structural Equation Modeling, I summarized main conclusions as follow. First, rule legitimacy and organizational identification have different effects on different rule behaviors. Perceived rule legitimacy and organizational identification have direct positive effect on rule deference. But the effects of legitimacy on rule-compliance and rule-breaking are moderated by organizational identification and value internalization. Only under high identification or value congruence with organization, could legitimacy perception predict rule compliance and breaking. Second, individual formalism (IF) has positive effect on rule compliance. IF’s positive effect on rule deference only appear under high value congruence between individuals and organization. Third, organizational identification works as a “valve” in the relationship between individual viewpoints and rule-breaking. Organizational identification turns off the tendency of utilitarianism to break rules, and turns on the tendency of formalism to inhibit rule-breaking. Forth, attitudinal and behavioral facets of utilitarianism and formalism have different influences on rule-following behaviors. Only individuals who are both attitudinal and behavioral formalists show deference to rules, while formalism as behavioral tendency predicts less rule-breaking. Fifth, innovation behaviors coexist independently with compliance and deference to rules. But the division between innovation and rule-breaking is obscure. Organizational identification facilitate both rule following and innovation. Sixth, women comply with rules more than men do, while men break more rules than women do. More aged people develop deeper identification with their organizations, and higher deference to rules. Individuals with higher education are fewer formalists, and accordingly defer to rules less and break more.

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This study is aimed at examining the degree of the basic scales (validity scales and clinical scales) between The Chinese MMPI and MMPI-2. Four samples (include schizophrenia, affective disorder, neuroses and normal subjects) of 236 subjects completed MMPI/MMPI-2 Combined Questionnaires in groups. The concordance rate for total code types was 90.1%. For 1-point, 2-point, 3-point and elevated code types, they were separately 81.6%, 65.8%, 49.2%, 64%. Only 56.8% of men compared to 73.8% of the women showed concordance in 2-ponit code types between MMPI and MMPI-2. And 58% of normal subjects compared to 48% of the schizophrenia subjects showed concordance in 3-point code types. Of the 236 cases, 156 (66.1%) had code types that were "well-defined" (1-, 2- or 3-point). 1-point, 2-point, 3-point well-defined code types respectively were 38.6%, 29.7%, 21.6%. For 2-point code types which were well-defined, the concordances was 84.3%, 82.8%, 85.7% (all the cases, men, women), higher than 64.4%, 56.8%, 72.9% when they were free-defined. 96.4% of subjects with incongruent 2-point code types had one of the scales in their MMPI code types with MMPI-2 code types. When deference caused by the use of uniform T-scores and new norms in MMPI-2 were found, the differences typically in code types congruence were not very great. Comparison of mean scores for the validity and clinical scales, 7 raw scores and 12 T-scores showed significant difference for MMPI versus MMPI-2 (Form). In spite of significant mean differences, correlational analyses show correlations above 0.92 for the raw scores and T-scores for each gender. All these results showed the good consistence between MMPI and MMPI-2 in basic scales, and showed MMPI-2 should be studied deeply.