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Search Results: 1 - 10 of 144 matches for " Assem Hedayat "
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Theoretical Application of Irreversible (Nonequilibrium) Thermodynamic Principles to Enhance Solute Fluxes across Nanofabricated Hemodialysis Membranes
Assem Hedayat,Hamdi Elmoselhi,Ahmed Shoker
International Journal of Nephrology , 2012, DOI: 10.1155/2012/718085
Abstract: Objective. Nanotechnology has the potential to improve hemodialysis membrane technology. Thus, a major objective is to understand how to enhance toxic solute fluxes across these membranes. The aim of this concept building study is to review the application of irreversible thermodynamic (IT) to solute fluxes. Methods. We expanded the application of the Nernst-Planck equation to include the Kedem-Katchalsky equation, pH, membrane thickness, pore size, and electric potential as variables. Results. (1) Reducing the membrane’s thickness from 25?μm to 25?nm increased the flux of creatinine, -microglobulin, and tumor necrosis factor-α (TNF-α) by a thousand times but prevented completely albumin flux, (2) applying an electric potential of 50–400?mV across the membrane enhanced the flux of the respective molecules by , , and ?mol/s, and (3) changing the pH from 7.35 to 7.42 altered the fluxes minimally. Conclusions. The results supported an argument to investigate the application of IT to study forces of fluxes across membranes. Reducing the membrane’s thickness—together with the application of an electrical potential—qualities achievable by nanotechnology, can enhance the removal of uremic toxins by many folds. However, changing the pH at a specific membrane thickness does not affect the flux significantly. 1. Introduction Irreversible (nonequilibrium) thermodynamics (IT) is a descriptive and powerful tool to delineate the contribution of forces responsible for fluid movements across membranes. Both Soltanieh and Gill [1] and Sievertsen [2] presented excellent reviews summarizing the differences between IT and kinetic transport models. Kedem and Katchalsky [3] stressed that kinetic equations describing volume and solute flow do not fully describe a membrane’s physical behavior. They also pointed out to the quantitatively incomparable results of permeability data obtained by different methods. Kedem and Katchalsky resolved this issue by applying IT methods to address membrane transport processes. The principle is to identify the constituent, independent, and elemental processes within the system (diffusion, convection, and so forth…). Then, each process is represented by a set of flux and conjugate force, where there is a relationship between the flux (flow) and the force (free energy gradient) causing it. All these parallel processes of fluxes and conjugate forces can be summed up [4, 5]. Hemodialysis is a life-saving procedure to treat patients with kidney failure. During hemodialysis treatment, the human blood is filtered through a semipermeable membrane to
The Peculiarities of Gratitude Expression Use in the Foreign Language (on the Example of English)  [PDF]
Saltanat Meiramova, Assem Kulzhanova
Open Journal of Social Sciences (JSS) , 2015, DOI: 10.4236/jss.2015.36004
Abstract:

It is known that expressing gratitude is one of the most frequently occurring communicative acts in most languages in the world. According to Nofsinger [1999:29], thanking is a speech act, specifically classified under expressive, which are “expressions of the speaker’s psychological state about something (an event, an object, a behaviour, or whatever).” Also, the general idea is that thanks maybe viewed as unimportant routine formulae. This paper attempts to investigate the linguistic and semantic characteristics of gratitude expressions’ use in the English language by Kazakhstani EFL students of higher school. In addition, the paper tries to determine the impact of social factors on the way the gratitude is expressed and also show the importance of thankfulness when it is missing in situations in which it is expected. To do so, the practical analysis of gratitude expressions’ use in oral speech has been done. Sixty people were selected from among students of Gumilyov Eurasian National University to collect data through a discourse completion task (DCT) adapted from Eisenstein and Bodman (1993). The results of the study show that the most frequently used gratitude expressions by Kazakhstani EFL students are expressions of happiness, thankfulness and best wishes in oral speech informal style.

Large liver abscess: Unusual presentation of fascioliasis: Case report and literature review
Riazi Hedayat
Saudi Journal of Gastroenterology , 2001,
Abstract:
The oral novel in history
Assem Eldessouki
Historical Kan Periodical , 2009,
Abstract: . " " .
Separating Models by Formulas and the Number of Countable Models
Mohammad Assem
Mathematics , 2012,
Abstract: We indicate a way of distinguishing between structures, for which, two structures are said to be separable.Being separable implies being non-isomorphic. We show that for any first order theory $T$ in a countable language, if it has an uncountable set of countable models that are pairwise separable, then actually it has such a set of size $2^{\aleph_0}$. Our result follows trivially assuming the Continuum Hypothesis ($CH$). We work here in $ZFC$ (only without $CH$).
Distinguishing Models by Formulas and the Number of Countable Models
Mohammad Assem
Mathematics , 2013,
Abstract: We indicate a way of distinguishing between structures, for which, we call two structures distinguishable. Roughly, being distinguishable means that they diff?er in the number of realizations each gives for some formula. Being non-distinguishable turns out to be an interesting equivalence relation that is weaker than isomorphism and stronger than elementary equivalence. We show that this equivalence relation is Borel in a Polish space that codes countable structures. It then follows, without assuming the Continuum Hypothesis, that for any fi?rst order theory in a countable language, if it has an uncountable set of countable models that are pairwise distinguishable, then actually it has such a set of continuum size. We show also, as an easy consequence of our results, that Vaught's conjecture holds for the language with only one unary relation symbol.
A Characterization of Modules with Cyclic Socle
Ali Assem
Mathematics , 2015,
Abstract: In 2009, J. Wood [15] proved that Frobenius bimodules have the extension property for symmetrized weight compositions. Later, in [9], it was proved that having a cyclic socle is sufficient for satisfying the property, while the necessity remained an open question. Here, landing in Midway, the necessity is proved, a module alphabet RA has the extension property for symmetrized weight compositions built on AutR(A) is necessarily having a cyclic socle.
On substitution algebras of permutations
Mohammad Assem
Mathematics , 2013,
Abstract: The subject of this paper is a simulation to that in [1] but here we consider substitutions corresponding to transpositions instead of replacements.
On Symmetrized Weight Compositions
Ali Assem
Mathematics , 2014,
Abstract: A characterization of module alphabets with the Hamming weight EP (abbreviation for Extension Property) had been settled. A thoughtfully constructed example by J.A.Wood finished the tour. Frobenius bimodules were proved to satisfy the EP with respect to symmetrized weight compositions. In 4, the embeddability in the character group of the ambient ring R was found sufficient for a module RA to satisfy the EP with respect to swc built on any subgroup of AutR(A), while the necessity remained a question. A least action trial suggests bridging to the already settled case, a trial that turns out to be successful. Here, landing in a Midway, the necessity is proved by jumping to Hamming weight. Corollary 1.11 declares a characterization of module alphabets satisfying the EP with respect to swc
Estimation of Basal Area in West Oak Forests of Iran Using Remote Sensing Imagery  [PDF]
Loghman Ghahramany, Parviz Fatehi, Hedayat Ghazanfari
International Journal of Geosciences (IJG) , 2012, DOI: 10.4236/ijg.2012.32044
Abstract: The objective of this study is to evaluate the capability of satellite imagery for the estimation of basal area in Northern Zagros Forests. The data of the high resolution geometric (HRG) sensor of SPOT-5 satellite dated in July 2005 were used. Investigation of the quality of Satellite images shows that these images have no radiometric distortion. Overlaying of geocoded images with the digital topographic maps indicated that the images have high geometric precision. A number of 319 circular plots (0.1 ha) were established using systematic random method in the study area. All trees having diameter at breast height (DBH) (i.e. 1.3 m above ground) greater than 5 cm were callipered in each plot. Basal area in each plot was determined using field data. Main bands, artificial bands such as vegetation indices and principle component analysis (PCA) were studied. Digital numbers related to each plot were extracted from original and artificial bands. All plots were ordinated by major geographic aspects and the best fitted regression models were determined for both the study area without consideration of aspects and with consideration of major geographic aspects by multiple regression analysis (step wise regression). The results from regression analysis indicated that the square root of basal area without consideration of aspects has a high correlation with band B1 (r = –0.60). The consideration of aspects resulted in correlation of different indices with square root of basal area such that in northern forests, band B1 had higher correlation coefficient(r = –0.67) among other indices. In Eastern forests, the same band showed correlation of basal area with different correlation coefficient (r = –0.65). In southern and western forests, the square root of basal area had higher correlation (r = –0.68) with RVI. The use of the square root of basal area as a dependent variable in multivariate linear regression improved the results. The assessment of model validity indicated that the proposed models are properly valid.
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