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    Trends Journal of Sciences Research 2015, 2(2), 73-75. 10.31586/Surgery.0202.04
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    Abstract
    The aneurysm is a complex phenomenon which is affected by different factors, such as the biological diseases and the blood flow parameters. The wall shear stress and pressure are the main factors in the establishment and growth of cerebral aneurysm. The circle of Willis is a prevalent location for aneurysm.
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    The aneurysm is a complex phenomenon which is affected by different factors, such as the biological diseases and the blood flow parameters. The wall shear stress and pressure are the main factors in the establishment and growth of cerebral aneurysm. The circle of Willis is a prevalent location for aneurysm. On the other hand, the anomalies of circle of Willis cause variations in flow field pattern and also the wall shear stress and pressure. In the present study, the effects of some anomalies in the flow pattern are investigated using three dimensional simulation of the Circle of Willis. The simulations are conducted using commercial ANSYS FLUENT. The obtained results show the major anomalies cause increase wall shear stress and pressure on the wall of circle of Willis. This factor can lead to increase the risk of aneurysm.Full article
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    Trends Journal of Sciences Research 2015, 2(2), 76-83. 10.31586/Education.0202.05
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    Abstract
    The study presented here aimed to grasp, interpret and understand the processes of construction of knowledge developed by the Specialization Course in Education Program (PPGE) at UFAM (Universidade Federal do Amazonas ? Amazonas Federal University). The dip in their doings, in the society and culture in which it is located,
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    The study presented here aimed to grasp, interpret and understand the processes of construction of knowledge developed by the Specialization Course in Education Program (PPGE) at UFAM (Universidade Federal do Amazonas ? Amazonas Federal University). The dip in their doings, in the society and culture in which it is located, has enabled us to grasp the immense plot and the network of meanings woven by the energy that emerges from the life of Amazonian subjects and their world which transcend, by far, the pure beams of logical relationships where humans are treated as clones, doomed to an eternal repetition. The analysis have articulated the researchers? perceptions, the theoretical conceptions and the data collected and revealed the richness and fertility of those cultures and the meaning of that Program, which has its support in local knowledge with insertion in the universal context.Full article
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    Trends Journal of Sciences Research 2015, 2(2), 64-72. 10.31586/Physics.0202.03
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    Abstract
    In the present paper, we propose an explanation of the ambiguity of the results of experiments on the study of high-temperature superconductivity of ammonia systems. At the heart of the theoretical interpretation of the experiments, we put the bipolaron model. In this study, we have shown mathematically that the barrier
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    In the present paper, we propose an explanation of the ambiguity of the results of experiments on the study of high-temperature superconductivity of ammonia systems. At the heart of the theoretical interpretation of the experiments, we put the bipolaron model. In this study, we have shown mathematically that the barrier of repulsion between polarons can be effectively reduced if the polarons are in the macroscopic dielectric layers, or capillaries. We constructed the theory of polaron states in the macroscopic dielectric layers. We specify the conditions under which the polarons are hold in the layer between dielectrics. It was found that the electrostatic image forces lead to the appearance of additional forces of attraction between polarons. These forces are conditioned by oscillations of polarons around the position of their fixation. Derivations are given of the upper and lower limits on the width of the gap in which the polaron oscillations are not suppressed. In this case take place disappearance Coulomb repulsion of the polarons. A long-range resonant interaction of two oscillators resulting in the appearance of effective attraction between polarons is discussed. This leads to the formation of diamagnetic singlet bipolarons due to quantum exchange interactions and the effects of electron-electron correlations. For glass capillaries (quasi-one-dimensional bipolaron) and for gap between glass plates (quasi-two-dimensional bipolaron) we give quantitative estimates of the gap width and the critical temperature at which there is a barrier-free formation of the bipolaron in ammonia. Numerical estimates are obtained for a case of the bipolaron in ammonia. We got a quantitative evaluation, which indicate that the barrier-free formation of singlet bipolaron in ammonia begins at temperatures below 80K. As the experiment showed the electrical resistance of ammonia systems decreases abruptly by 10-12 orders of magnitude in this temperature range. At the same time, experiments have shown that for the bulk superconductivity superconducting phase is only ~ 0.01%.Full article
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    Trends Journal of Sciences Research 2015, 2(2), 56-63. 10.31586/Physicochemical.0202.02
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    Abstract
    The PbTe films were deposited onto glass substrate (microscopic slices) by a chemical bath method (CBD) at room temperature. The deposited films are dense, smooth, and uniform with silver gray metallic luster structure. Using XRD, it found that the structure of PbTe possesses stable face centered cubic (fcc) phase. The
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    The PbTe films were deposited onto glass substrate (microscopic slices) by a chemical bath method (CBD) at room temperature. The deposited films are dense, smooth, and uniform with silver gray metallic luster structure. Using XRD, it found that the structure of PbTe possesses stable face centered cubic (fcc) phase. The grain size of the PbTe bulk increased within the range of 33? 57 nm with annealing temperature increasing. AFM micrographs of surface of the prepared film are observed that horizontal distance in the rang (230? 395) nm. The band gaps of the PbTe are determined from UV-Vis spectrophotometer and are found to be within the range ( 0.39 - 0.95) eV. Energy band gab of PbTe which determined from FT -IR spectrophotometer is (0.36ev). The activation energy varied from 0.35- 1.72 eV for films and from 0.11-0.34 eV for bulk with annealing temperature variations from 373-573K. Films and bulk exhibit p-type conduction and resistivity in the range (75?10-4 ?. cm - 146?10-4 ?.cm). The carriers density and Hall mobility in PbTe bulk were in the rang 5.8 ?1023 m-3 and 4.004 m2/Vs.Full article
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    Trends Journal of Sciences Research 2015, 2(2), 50-55. 10.31586/Management.0202.01
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    Abstract
    Organizational citizenship behavior (OCB) as a non-mandatory cooperation with others significantly influences an organization?s performance and social capital. In this paper it has been attempted to study the role of personality traits based on the Big Five model namely, extraversion, agreeableness, conscientiousness, openness to experience and neuroticism in the performing
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    Organizational citizenship behavior (OCB) as a non-mandatory cooperation with others significantly influences an organization?s performance and social capital. In this paper it has been attempted to study the role of personality traits based on the Big Five model namely, extraversion, agreeableness, conscientiousness, openness to experience and neuroticism in the performing of organizational citizenship behavior, while Altruism, civic virtue, organizational conscientiousness, courtesy and sportsmanship were regarded as the main OCB dimensions. Correlation analysis on data from 56 employees of ?Bank Mellat? of Tehran, revealed that there was a significant relationship between personality characteristics and OCB. The present study suggests that conscientiousness, agreeableness and emotional stability positively affect OCB. Also according to the regression model conscientiousness is the best factor to predict OCB. The current research demonstrates that neuroticism is negatively related to OCB, since it diminishes a person's ability to avoid complaining while facing organizational problems.Full article