The present work described the influence of POLYMER admixture (i.e. POLYMER latexes) contents on the physical/mechanical properties of latex modified concretes (LMCs). At the first step, the optimum water to cement ratio was determined for a LMC concrete according to the results of compressive strength. Afterwards, six latexes were investigated as admixture for LMCs at 10% of latex content. Their physical and mechanical properties including compressive strength, flexural strength, splitting tensile strength and capillary water absorption was evaluated. Finally, two latexes which were better in LMCs general properties (i.e. Acrylic and Co-POLYMER Acrylic) were incorporated at 5 and 15% of latex contents to concrete. The result have shown that the increase in the amount of latex content decreased the compressive strength, but the other properties including flexural strength and split tensile strength were improved. Also, an improvement in barrier efficiency for water absorption of LMC concrete with increment of latex content was observed.

Paratuberculosis caused byMycobacterium avium subsp. paratuberculosis (Map) is a progressive, chronic and noncurable granulomatous enteritis. Paratuberculosis affects ruminants worldwide. The earliest reports on paratuberculosis in Iran date back to 1960’s when the disease was diagnosed in imported animals of the Abadan Oil Company’s farm. In the work presented here 13 field MAP isolates including 4 ovine and 3 caprine isolates from Isfahan, 6 bovine isolates from Zanjan and Alborz provinces plus 2 vaccinal strains of 316F and III & V were subjected to PCR-IS900, PCR-F57 for identification and also PCR-Collins for typing. In consequence, while an identical PCR protocol was successfully developed to simultaneously perform all the three experiments, the 15 tested bacteria were all shown to be MAP TYPE II (cattle TYPE). In epidemiological sense, when the size of national goat, sheep and cattle herds of Iran is taken into account, circulation of MAP TYPE II is intriguing.

Purpose: To report histopathological findings for different TYPEs of POLYMERs proposed as support for a Pintucci-TYPE keratoprosthesis. Methods: Six POLYMERs, including three TYPEs of polyesters (#1-3), one TYPE of polytetrafluoroethylene (PTFE, #4), polyethylene (#5), and expanded polytetrafluoroethylene (ePTFE, #6) were evaluated. Four samples of each material were placed under the orbicularis oculi muscles of 12 rabbits. After five weeks, the samples were removed and evaluated histopathologically. Fibrovascular tissue ingrowths were investigated in terms of tissue penetration depth into the materials (graded as none, mild, moderate, and intense) and fibrovascular ingrowth area at the ultimate level of tissue penetrance. ImageJ software was used to calculate fibrovascular tissue area between the material fibers, and the mean area values were compared between the materials. Results: Polyester materials #1 and #3 demonstrated intense fibrovascular tissue penetration with a large fibrovascular ingrowth area,no overt tissue ingrowth was observed into material #6. The mean area of penetrated fibrovascular tissues was significantly different between materials (𝑃,< 0. 001). Materials #2, #4, and #5 showed moderate fibrovascular tissue ingrowth and the area of presented fibrovascular tissue at the paracentral parts of material #4 was significantly smaller than that of materials #1 (𝑃,= 0. 02) and #3 (𝑃,= 0. 01). Conclusion: Two polyester materials that had relatively large pore sizes demonstrated a deep and large area of fibrovascular ingrowth. Given that material #3 is thicker and more consistent than material #1, the former can be used as the appropriate material for supporting the Pintucci-TYPE keratoprosthesis.

Background: Donepezil (DON) is a reversible and non-competitive cholinesterase inhibitor and a well-known drug for treatment of Alzheimer’s disease. The main objective of this study was to prepare an oral dosage form of DON with gradual drug release characteristics in order to reduce the gastrointestinal side effects and increase patient compliance. For this purpose DON was intercalated into montmorillonite (MMT) and drug release was manipulated by inclusion of different POLYMERs into DON-MMT hybrids.Methods: DON-MMT hybrids were prepared and the effects of drug concentration and temperature on drug loading were evaluated. To achieve the desired release profile, DON-MMT hybrids were dispersed separately into a solution of carbomer, chitosan, sodium alginate, or Eudragit. The resultant suspensions were spray-dried separately. The weight fraction of hybrid to the POLYMERs was 1.0: 1.0, 1.0: 0.6, and 1.0: 0.3. All prepared nanocomposites were tested for drug loading capacity and drug release profiles. The surface morphology of optimized nanoparticles was analyzed by scanning electron microscopy.Findings: The highest drug loading (16.8%) was achieved by nanocomposites containing 2 mM DON prepared at 70oC (formulation coded D2MMT70). The lowest drug loading (12.3%) belonged to hybrids coded D1MMT25 prepared at 25oC. Among four POLYMERs, Eudragit L100-55 and sodium alginate had more distinct effect than carbomer or chitosan on drug release from the DON-MMT hybrids. Cumulative drug release from nanocomposites coded as H1AL1 was 34.0% and 18.84% in hydrochloric acid and phosphate buffer, respectively.Conclusion: Increasing temperature to 70oC could increase drug loading during the preparation of hybrids. Drug release rate from hybrids could be certainly manipulated by the presence of sodium alginate or Eudragit L100-55.

The shape and geometry of the flow field have considerable effects on the transfer rate of the reactants toward the catalyst layer and consequently the performance of the POLYMER electrolyte membrane (PEM) fuel cell. In this study, a novel PEM fuel cell with pin-TYPE flow field is proposed in order to reduce the wake regions, increase the oxygen transfer rate into the catalyst layer and the current density, and finally improve the fuel cell performance. To assess the performance of the proposed fuel cell, it is numerically simulated based on the computational fluid dynamics and the single-domain approaches and compared with that of a PEM fuel cell with parallel channels for the same geometry and operating conditions. The numerical results show that oxygen transfer rate into the gas diffusion layer and cathode catalyst layer is increased due to the existence of the pins in the proposed flow field. Comparing with the parallel channels, the pin-TYPE fuel cell has an improved performance as the current density is increased, especially for high current density value. However, the pin-TYPE fuel cell exhibits a higher pressure drop and non-uniform distribution of the current density.

Hydrophilic and Hydrophobic POLYMERs are widely used excipients to control the release of active ingredients from matrices. In this research the effect of various parameter (TYPE of POLYMERs and their concentrations). On the release rate of atenolol were investigated. Four POLYMERs namely Eudragit RSPO, HPMC K4M NaCMC and EC were used. The results showed that an increase in the Concentration of HPMC and EC in the matrices resulted in a reduetion in the release rate of atenolol. As the amount of Eudragit was increased in HPMC matrices the release rate of atenolol was not significantly changed (HPMC: Eudragit 3:1). When the ratio of HPMC: Eudragit was 1:1 the release rate of atenolol Significantly increased. The results showed that the release rate of atenolol from NaCMC matrices is similar to HPMC matrices at pH 1.2, but the release rate at pH 6.8 significantly increased. It can be concluded that the TYPE and concentration of POLYMERs are able to control the release rate of atenolol from matrices formulations.

This study synthesised nanocomposites by incorporating selenium nanoparticles into POLYMERic materials, specifically polyethylene oxide (PEO), polyvinyl alcohol (PVA), and poly(methyl methacrylate) (PMMA). The investigation focused on their linear, nonlinear, structural, and formal optical properties. The properties of nanocomposites can be enhanced by incorporating them into POLYMERic materials appropriate for various applications. Nanocomposites are significant in nonlinear optics (NLO) owing to their substantial nonlinear response and broad spectral transparency. The three nanocomposites, Se+PEO, Se+PVA and Se+PMMA, were prepared and characterised through XRD, FESEM, EDX, FTIR, RSS, and PL techniques. The linear optical properties of the prepared samples were analysed using UV-VIS spectroscopy at various concentrations achieved through the addition of different POLYMERs. The results indicated that an increase in concentration corresponded with a rise in absorbance at the same wavelength, with Se+PMMA exhibiting a higher absorbance compared to the other compounds. The fluorescence of all prepared samples was measured, and the results indicated that an increase in concentration led to a decrease in fluorescence. The Z-Scan technique, encompassing both open and closed aperture measurements, was employed to determine the nonlinear refractive index (n2) and the nonlinear absorption coefficient (β). The experiment utilised a solid-state diode laser operating at a wavelength of 405 nm and a power output of 2.94 mW. The Se+PMMA composite exhibits superior nonlinear behaviour compared to the other nanocomposites.