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1.
The authors used testimonies of students on the dominant motives of joining a higher education institution as the behavioral model that prefers a high probability of the attainment of a goal or its subjective value. They compared the features of the motivation sphere related to the choice of profession with the psychophysiological data of 38 students of a sports higher education institution. The motivation of this choice was determined using a test questionnaire that permitted the authors to measure the subjective value (importance) and accessibility (probability of attainment) of the selected profession. The psychophysiological features were evaluated on two levels, i.e., formal dynamic (temperamental characteristics) and physiological (frequency and amplitude characteristics of EEG). The athlete students’ motivating factor of the choice of profession was shown to form under the influence of individual and typological features, which manifest themselves in psychomotor activity and total ergicity (working capacity), while accessibility experiences a negative influence of the temperamental characteristics in the intellectual sphere, as well as the total ergicity level. The background EEG was more activated in those who chose sports as their profession because of deeming it more valuable. In students who were attracted by the accessibility of this field, a lower cerebral activation level was observed, especially in the frontal zones of the left hemisphere.  相似文献   

2.
In 70 Ss EEG coherence, amplitude and frequency characteristics as well as formal-dynamic (temperamental) properties were compared with the two dimensions of motivation involved in the choice of profession--its subjective "value" and the probability of its achievement ("accessability"). It was shown that the persons orienting themselves to the subjective value of the future profession tend to possess those features of temperament that testify to the stronger, more mobile and more labile nervous system as distinct from the subjects orienting themselves to the higher level of accessability. It was also shown that the persons with a higher level of the subjective value had a much higher level of EEG cortical activation in both hemispheres of the brain. The subjects with higher magnitudes of "accessability" were characterized by a lower level of brain activation.  相似文献   

3.
A finite conflict with given payoff matrix may have many ESS's (evolutionarily stable strategies). For a given set of pure strategies { 1, 2, ...,n} a set of subsets of these is called a pattern, and if there exists ann ×n matrix which has ESS's whose supports (i.e. the playable strategies) precisely match the elements of the pattern, then the pattern is said to be attainable. In [5] and [10] some methods were developed to specify when a pattern was, or was not, attainable. The object here is to present a somewhat different method which is essentially recursive. We derive certain results which allow one to deduce from the attainability of a pattern for givenn the attainability of other patterns forn+1, and by induction for anyn+r.  相似文献   

4.
In this paper, the attainability of ESS of the evolutionary game among n players under the frequency-independent selection is studied by means of a mathematical model describing the dynamical development and a concept of stability (strongly determined stability). It is assumed that natural selection and small mutations cause the phenotype to change gradually in the direction of fitness increasing. It is shown that (1) the ESS solution is not always evolutionarily attainable in the evolutionary dynamics, (2) in the game where the interaction between two species is completely competitive, the Nash solution is always attainable, and (3) one of two species may attain the state of minimum fitness as a result of evolution. The attainability of ESS is also examined in two game models on the sex ratio of wasps and aphids in light of our criterion of the attainability of ESS.  相似文献   

5.
Knowledge of the dynamic features of protein interfaces is necessary for a deeper understanding of protein–protein interactions. We performed normal‐mode analysis (NMA) of 517 nonredundant homodimers and their protomers to characterize dimer interfaces from a dynamic perspective. The motion vector calculated by NMA for each atom of a dimer was decomposed into internal and external motion vectors in individual component subunits, followed by the averaging of time‐averaged correlations between these vectors over atom pairs in the interface. This averaged correlation coefficient (ACC) was defined for various combinations of vectors and investigated in detail. ACCs decrease exponentially with an increasing interface area and r‐value, that is, interface area divided by the entire subunit surface area. As the r‐value reflects the nature of dimer formation, the result suggests that both the interface area and the nature of dimer formation are responsible for the dynamic properties of dimer interfaces. For interfaces with small or medium r‐values and without intersubunit entanglements, ACCs are found to increase on dimer formation when compared with those in the protomer state. In contrast, ACCs do not increase on dimer formation for interfaces with large r‐values and intersubunit entanglements such as in interwinding dimers. Furthermore, relationships between ACCs for intrasubunit atom pairs and for intersubunit atom pairs are found to significantly differ between interwinding and noninterwinding dimers for external motions. External motions are considered as an important factor for characterizing dimer interfaces.  相似文献   

6.
The frequency of sleep disturbances is considerably higher in the night and shift workers and in females than in day workers and males, respectively. However, a subjective sleep scale must be invariant across these groups, independently of the level of their members on the scale. This study is aimed to test the invariance of the Karolinska Sleep Questionnaire’s (KSQ) items by shift work and sex. We used the data from a census that covered more than 90% (N = 1648) of the nurses from the main institute of the largest public hospital complex of Brazil. Firstly, we intend to find the KSQ’s dimensionality using factorial analysis and Item Response Theory (IRT) performed by Graded Response Model. Differential Item Functioning (DIF) was the technique used to test the invariance of each KSQ’s dimensions. In case of variance detection, we applied the linking analysis. Intending to test the KSQ’s consistency with external variables, we assessed correlations between KSQ’s dimensions with health variables, i.e., self-reported health status and musculoskeletal pain. We have found one scale and two subscales from one general and another bidimensional factor structure of the KSQ, respectively. In these dimensions, the KSQ’s items fitted well to the IRT and we have identified DIF by shift work. However, we have found DIF by sex just in one item on the general factor. Linking analysis showed as a possible step forward in the variance issue placing on to the same scale the shift work groups in the items with DIF. All correlations between KSQ’s dimensions with health variables were significant. Our findings allow us to argue that KQS’s items were variant by shift work and sex in a nursing staff census from the largest public hospital complex of Brazil, but we can go on using linking analysis. This could be used as an evidence for the construct validity should go beyond the traditional dimensionality assessment. The dimensionalities of KSQ fit well for other population but individuals living in Scandinavian countries.  相似文献   

7.
Event-related EEG potentials (ERP) were recorded from 75 tested adult men and women; recording was performed from C3 and C4 points. The experimental situation required internal counting of time intervals limited by two pushes of a button. The experimental paradigm provided a substantial level of uncertainty, and a high level of attention needed to be maintained. The tested subjects were not informed by the experimenter about the precise value of the preset time interval; they knew only its limits, 17–23 sec. The subject obtained information about the agreement or disagreement between the produced interval and its value preset by the experimenter by visual feedback signals obtained 2 sec after termination of counting; in the case of agreement the subject had to perform a confirming (third) push of the button. Pushes were preceded by readiness potentials (RP); contingent negative variation (CNV) developed before the feedback signals, and the latter were accompanied by P300 potentials. Significant positive correlations were found between the parameters of RP and P300 in both hemispheres. In general, ERP were characterized by very high interindividual variability, which in a few respects correlated with the personality-related characteristics of tested subjects evaluated by psychological testing with the use of corresponding questionnaires. In particular, under the experimental conditions used, negative correlations were observed between the RP amplitude and psychotism indices, CNV amplitude and emotional stability; CNV amplitude and extroversive features, and P300 amplitude and domination properties of a person. Positive correlations were observed between the CNV amplitude and autia factor (according to Eysenck’s PEN and Cattell’s 16 PF questionnaires). We suppose that correlations between the personal psychical features and ERP parameters are grounded in both inherited constitutional specificities of the nervous system and neurochemical/structural modifications in the brain determined by the acquired vital experience.  相似文献   

8.
9.
Summary In vitro-stored plant germplasm is usually evaluated by visual analysis of the plant based on subjective characters. To reduce the variability in these evaluations, we developed a digital-image evaluation system for in vitro-stored plantlets. This study compares the standard visual evaluation system with a digital analysis system to determine if digital analysis can effectively quantify the health of diverse Humulus germplasm. Eight cultivars of Humulus lupulus L. were stored on standard Murashige and Skoog (MS) medium with iron alone (EDTA chelated) and on MS iron with 100 or 200 mgl−1 sequestrene 138 iron (EDDHA chelated). Digital images of the upper two nodes of each plantlet were evaluated for red, green, blue, green/red ratio, and modified normalized difference vegetation index (MNDVI=R-G/R+G). Evaluation of each plantlet for MNDVI values showed consistent significant differences for all treatments only at the upper node. Significant differences for visual and the MNDVI values among the three iron treatments were observed at the upper node of most of the eight hop cultivars. Regression analysis of the upper node MNDVI values vs. whole-plant visual ratings showed positive correlations for most cultivars. Effects of iron treatments on storage duration were also analyzed for both visual and digital systems. There were significant differences among MNDVI values for plantlets stored on medium with standard MS iron alone (EDTA chelated) and with the addition of sequestrene 138 iron. In general, the MNDVI value of the upper node correlated well with visual ratings and could be used to determine the health of in vitro stored hops.  相似文献   

10.
The objective of this study was to quantify the effect of fungal biomass concentration on the rheology of non-Newtonian fermentation systems. Batch fermentations of Penicillium chrysogenum were carried out with glucose as the sole carbon source. The flow behavior of the system was characterized at various fermentation times and was adequately described by the power-law model. The apparent viscosity of the fermentation broth was significantly affected by biomass concentrations in the fermenter. Fermentation broths containing 17.71 g/l biomass as dry weight were characterized by an apparent viscosity of 0.25 Pa s at a shear rate of 50 s−1. Microbial concentration also affected the power-law flow-behavior index and the consistency index. The value of the consistency index ranged from 0.002 Pa s n at a biomass concentration of 0.1 g/l to 6.14 Pa s n at a biomass concentration of 17.71 g/l. The flow-behavior index decreased from an initial value of 1 to a final value of 0.17. Simple empirical correlations have been proposed to quantify the dependence of the power-law parameters on fungal biomass concentration. Experimental data obtained in this study were accurately described by these correlations. The general applicability of these relationships was tested, using previously published rheological data on Aspergillus awamori and Aspergillus niger fermentation broths, and good agreement was seen between experimental data and the predictions from the empirical correlations. Received: 24 March 1998 / Received revision: 10 September 1998 / Accepted: 16 October 1998  相似文献   

11.
Forty-one type and reference strains of Lactobacillus were evaluated using their randomly amplified polymorphic DNA band profiles. Developed bands for each strain were distinct and enabled discrimination. The best correlations were obtained applying the Pearson product moment correlation coefficient (r) together with the unweighted pair group method using arithmetic averages algorithm. All of the strains were clearly differentiated at and below the 72% similarity value. Species discrimination might be possible making use of the distinctly polymorphic bands amplified specific to a strain.  相似文献   

12.
α‐MgAgSb is recently discovered to be a new class of thermoelectric material near room temperature. A competitive ZT of 1.4 at 525 K is achieved in Ni‐doped α‐MgAgSb, and the measured efficiency of energy conversion reaches a record value of 8.5%, which is even higher than that of the commercially applied material bismuth telluride. On the other hand, the band structure of α‐MgAgSb is believed to be unprofitable to the power factor, owing to the less degenerate valence valleys. Here, this paper reports a systematic theoretical study on the thermoelectric properties by using the electron/phonon structure and transport calculations. Based on the careful analysis of Fermi surface, a principled scheme is presented to design band engineering in α‐MgAgSb. Following the given rules, several effective dopants are predicted. As two examples, Zn‐ and Pd‐doped α‐MgAgSb are numerically confirmed to exhibit an extraordinary ZT value of 2.0 at 575 K and a high conversion efficiency of 12.6%, owing to the effects of band convergence. This work develops an applicable scheme for the purposive design of band engineering, and the idea can be simply applied to more thermoelectric materials.  相似文献   

13.
We present a method to evaluate ecological characteristics of small shallow ponds in Central Mexico based on video remote sensing and image processing techniques in a GIS environment. We used a set of color video imagery obtained from heights lower than 700 m above ground. Our analysis established statistical correlations between the average reflectance values contained in video imagery (digital numbers DN per Blue-Green-Red band) and the average values of limnetic variables: (1) water suspended solids concentration; (2) water turbidity; (3) total macrophytes coverage; (4) free floaters and emergent macrophytes coverage; (5) zooplankton abundance; and (6) chlorophyll-a concentration in water. We found strong correlation between DN values and vegetation presence, suspended solids concentration and water turbidity (R= 0.85 to 0.98), but weak correlations with phytoplankton and zooplankton abundance. This cheap and fast method can be used to describe general conditions of ponds related with vegetation abundance, turbidity and suspended solids.  相似文献   

14.
15.
The aim of this study was to provide validity for the Spanish version of the Morningness–Eveningness-Stability Scale – improved (MESSi), a novel evolved assessment of circadian typology which considers the subjective phase and amplitude by morning affect (MA), eveningness (EV) and distinctness (DI; subjective amplitude) sub-scales. Convergence validity of the MESSi with the reduced Morningness–Eveningness Questionnaire (rMEQ) and relationships with the General Health Questionnaire (GHQ-12) and sensitivity to reward and punishment (SR and SP) were analyzed. Two different Spanish samples, young undergraduate students (n = 891, 18–30 years) and adult workers (n = 577, 31–65 years) participated in this study. Exploratory structural equation modeling (ESEM) of MESSi displayed acceptable fit of a three-factors measurement model. Percentiles of the MA, EV and DI sub-scales were obtained for students and adults. The MESSi showed good convergence validity with the rMEQ scores, with a higher correlation coefficient between MA, EV and lower with DI sub-scales. In both, young students and adult workers, MA was negatively related with the GHQ-12 and SP, but the percentage of explained variance (6% and 3%) was lower than the positive correlations between DI, the GHQ-12 and SP (20% and 13%). Morning types presented higher MA and lower EV scores than the other two typologies in both students and adult workers, whereas only differences in DI were found among students (lowest in evening type). Candidates to psychological symptoms and mental disorders (“true cases”), with the clinical cut-off criteria of the GHQ-12, showed lower MA and higher DI in students, whereas only DI was higher for “true cases” among adults. These results supported that subjective amplitude is a factor related to, but also differentiated of, morningness–eveningness (preferred time for a certain activity). The measure of amplitude might be more important than circadian phase in health consequences.  相似文献   

16.
doi: 10.1111/j.1741‐2358.2011.00459.x
Relationship between subjective assessment of oral health and medical expenses in community‐dwelling elderly persons Objectives: The increasing medical expenses of elderly persons in Japan’s rapidly ageing society have become a major concern. It is therefore important to elucidate the factors associated with such escalation. Here, we focused on the relationship between subjective self‐assessment of oral health, as an index of general health, and medical expenses (excluding dental repair) under the hypothesis that oral health contributes to general medical expenses. Several studies have shown that oral health status is correlated with general health status among elderly persons. We speculated that oral health status might show a relation with medical costs among elderly persons. However, few studies have investigated this relationship to date. Materials and Methods: Participants were 259 elderly subjects (range: 65–84 years; 120 men, 139 women) residing independently. Subjective assessment of oral health was evaluated by their responses (‘Good’, ‘Not good’ and ‘Not at all good’) on a survey questionnaire. The correlation between subjective assessment of oral health and medical expenditure was analysed using Spearman’s rank method, the Mann–Whitney U‐test and the Kruskal–Wallis test. Medical expenses were used as the dependent variable in multinomial logistic regression analysis with background and intraoral factors as independent variables. Results: A slight yet statistically significant correlation was observed between subjective assessment of oral health and outpatient treatment fees. Conclusion: The findings revealed that subjective assessment of oral health is significantly and independently related to the medical expenses of community‐dwelling elderly persons after adjusting for social background, living environment and physical factors.  相似文献   

17.
Summary We have investigated whether the size heterogeneity of the human apolipoprotein (a) [apo(a)] is due to differences in the number of plasminogen kringle 4-like repeat units present in the different alleles. Using the Southern blot hybridization technique and a DNA probe for the kringle 4 domain of plasminogen, we have observed that in 31 different individuals a 5.8-kb PvuII restriction fragment band varies widely in intensity relative to other bands. A strong correlation (r=0.76, P<0.001) was found between apo(a) protein size and the variation in intensity of the detected restriction fragment band. We confirmed this correlation in a large family where the parents are heterozygous for the apo(a) protein size isoforms. The specificity of the 5.8-kb band was established by using an apo(a)-specific oligonucleotide. These correlations strongly suggest that the observed size heterogeneity in apo(a) protein is due to different numbers of copies of the kringle 4 sequence in the apo(a) glycoprotein gene.  相似文献   

18.
CdTe quantum dots, 3.28 nm in size, were synthesized using a one‐step method in an aqueous medium. The CdTe quantum dots were successfully employed as hybrid phosphors for white light‐emitting diode (LED) devices by combining them with yellow‐emitting YAG:Ce phosphor. The color‐rendering index value and International Commission on illumination coordinates for hybrid phosphor white LEDs were 75 and (x = 0.30, y = 0.29), respectively. Compared with conventional phosphors, semiconductor quantum dots have larger band gap energy and broader absorption features, and can be excited more efficiently by optical pumping sources. The results confirmed that the high color‐rendering index value of the white LED was due to the CdTe quantum dots introduced in the hybrid phosphor system. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

19.
Liming trials were conducted at 28 sites in the western Great Plains of Canada for barley, rape, red clover and alfalfa. Yield increases from liming correlated with soil pH and Al but not with Mn. When all sites were included, yield increases from liming correlated closely (r=0.86 to 0.94) with exchangeable Al, percent Al saturation and 0.02M CaCl2-Al for barley, rape and red clover, these responses having correlated less well (R=0.56 to 0.72) with soil pH. Alfalfa yield responses gave low correlations with both pH and the Al measurements. When only the sites with soil pH≥5 were used, the yield responses to lime of barley and rape still correlated better with the Al measurements than with pH even though the correlations, in general, were much lower than when all sites were included. For the sites with soil pH>-5, the correlations were highest for yield responses of barley and rape with 0.02M CaCl2-Al. It is suggested that the use of toxic Al and Mn for routinely diagnosing the limiting factor by soil acidity could improve on the economy of liming. Contribution Number 653.  相似文献   

20.
Within-locality correlations among eight morphological traits of the fundatrix and among 15 morphological traits of the alate fundatrigeniae of the aphid Pemphigus populicaulis Fitch were examined for among-locality variation. A jackknife procedure revealed highly significant differences among correlation matrices representing 34 local samples from eastern North America. Most bivariate correlations also differed significantly among samples. Although very low correlations cannot differ, for moderate or strong correlations the average magnitude of correlation is not a good predictor of the degree of interlocality difference. Nearly half of the variation among localities is in the level of “overall correlation,” which is positively correlated with intralocality size variation. Despite significant differences among localities, spatial autocorrelation tests failed to reveal any significant geographic pattern in correlations. Monte Carlo experiments suggest that if geographic patterns in the correlations were of the same magnitude as those for the means of these traits, some of these patterns would have been detected. Factor analyses of the pooled within-locality correlation matrices, after oblique rotation to simple structure, reveal appendage and body-size factors for both alates and stem mothers. In general, correlations between traits with high loadings on the same factor differ among localities, whereas substantial correlations that do not vary geographically are between traits that are not well resolved by the factor analyses. It is hypothesized that the apparently random geographic differences in correlation are caused by chance differences in the mode of response to short-term selection. Geographic patterns in trait means are established by selection, but, because local population sizes are finite, similar response to selection occurs by diverse physiological or developmental mechanisms in different populations, just as replicate lines in artificial selection experiments may achieve the same response by diverse mechanisms. These diverse mechanisms of response will have diverse effects on genetic variance and covariance, causing correlation patterns to vary geographically. Several forces will oppose continued divergence of these patterns.  相似文献   

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