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Introduction: Pyrazinamide (PZA) susceptibility testing plays a critical role in determining the appropriate treatment regimens for multidrug-resistant tuberculosis. We conducted a systematic revie...

Linear low-density polyethylene (LLDPE) cast stretch films were fabricated at broad range of line speeds (200–1000 m/min) to investigate the relationship between tensile properties of films and line speed of cast extrusion process, particularly high line speeds as a matter of scientific and economic interest. In addition, tensile experiments were carried out at low and high drawing speeds as well as in both machine and transverse directions (MD and TD). The results illustrated an enhancement of MD modulus (more than 100%) and strength (about 22%) with increasing the line speed from 200 to 1000 m/min, indicating a more pronounced increase for modulus values. Changing the drawing speed, generally, affected the high strain behavior of films. Nevertheless, at the lower strains, the drawing speed influences particularly the modulus of lower line speed films. It was observed that increasing the line speed in the cast film line has stronger effects on the film elongation behavior than the drawing speed in tensile tests. The tensile properties along TD showed greater deviations from MD tensile behaviors as line speed increased. The variations of tensile properties by line speed were due to chain orientation and extension especially in the amorphous phase. Furthermore, the surface morphology of the LLDPE films were also observed, and it was found that increasing the line speed leads to reduction of surface roughness.

Methamphetamine (METH) has been reported to induce social and recognition memory impairment. Evidence suggests that the cannabinoid system has an important modulatory role in cognitive processing and social interaction. Nonetheless, no previous study has investigated the probable role of the cannabinoids system on METH-induced deficits of novel object recognition (NOR) memory and social interaction. Adult male rats were given a neurotoxic METH regimen (four injections of 6 mg/kg, s.c, at 2 h intervals). One week later, they were examined for either NOR or social interaction in different groups. The cannabinoid type 1 receptor (CB

Cavitation (void formation) in high-density polyethylene cast films, having a stacked lamellar morphology, subsequent to tensile stretching of both nonirradiated and irradiated films was investigated. With nonirradiated films, the cavitation was not observed in the nonannealed films with lower draw ratios, while a limited number of voids was detected in the films of higher draw ratios. Annealing caused an intensive cavitation, and uniform distribution of cavities was noticed in highly oriented films. It was shown that cross-linking exerted a suppressive influence on cavitation in the annealed and oriented films; and with increasing the irradiation dose, the cavitation was completely eliminated.

One of the megaprojects under construction in the Isfahan metropolis is the project of the International Conference Center of the Isfahan Metropolis, which, despite the multidimensional and profound effects, has not yet been fully explored. Hence, the aim of this paper is to evaluate the megaproject of the international conference center of the Isfahan metropolis in terms of various physical, social, economic, managerial and environmental dimensions. Accordingly, the mixed research (combination of Qualitative and Quantitative methods) paradigms have been used. The data have been also collected by means of both document and survey methods (interview type). For evaluation and analysis, Likert scale, AHP method and Expert Choice software have been used. The results show that, despite the positive features of the Megaproject in the social, physical, and environmental sectors, this megaproject in the economic and management sector has major weaknesses, most notably is non-matching of costs with efficiency and non-achievement of objectives over the specified time. So there are some suggestions to address this defect. Streszczenie Jednym z megaprojektów budowanych w metropolii Isfahan jest projekt Międzynarodowego Centrum Konferencyjnego Metropolii Isfahan, które pomimo wielowymiarowych i dogłębnych analiz nie zostało jeszcze w pełni zbadane. Celem niniejszego artykułu jest ocena megaprojektu pod względem zróżnicowanych aspektów fizycznych, społecznych, ekono-micznych, zarządczych i środowiskowych. W związku z tym wykonano połączone badania – kombinację metod jakościowych i ilościowych. Dane zostały zebrane za pomocą zarówno dokumentów jak i metod sondażowych (typ wywiadu). Do oceny i analizy użyto skali Likerta, metody AHP i oprogramowania Expert Choice. Wyniki pokazują, że prócz pozytywnych cech megaprojektu w sektorach społecznym, fizycznym i środowiskowym, megaprojekt w sektorze gospodarczym i zarządzania ma wiele niedociągnięć a w szczególności wykazuje nieadekwatne odniesienie kosztów do osiągniętych celów w określonym czasie. Wprowadzone zostają sugestie naprawcze odnoszące się do tego błędnego rozwiązania.

Linear low density polyethylene (LLDPE) stretch films under different processing conditions in terms of line speed, air gap and film thickness are manufactured using a cast film line. The influence of processing parameters on crystal orientation in the cast LLDPE films is evaluated by wide angle X-ray scattering (WAXD). Diffraction patterns reveal no preferred crystal orientation in the cast films. To evaluate the amorphous orientation, shrinkage measurements are carried out in the both machine direction (MD) and transverse direction (TD). It is found that higher line speeds lead to a higher MD shrinkage in the films, and some TD shrinkages are also noticed in the films prepared at high line speeds. However, no significant differences are observed in the shrinkage behavior off films as air gap and film thickness change. The shrinkage detected in the cast films of high line speeds is taken as a measure of chain orientation in the amorphous phase.

The microstructure and crystalline morphology of high density polyethylene (HDPE) cast films prepared in a wide range of draw ratios (1.6 to 148.8) were investigated. The flow-induced orientation of crystalline and amorphous phases was characterized using Fourier transform infrared spectroscopy (FTIR). The results showed that the draw ratio has a crucial role on the orientation state of the cast films. Scanning electron microscopy (SEM) images also confirmed this influence. The crystallinity of the films was examined using both differential scanning calorimetry (DSC) and Raman spectroscopy. Moreover, considering a three-phase structure (i.e. crystal, amorphous and interphase) for semi-crystalline polyethylene, Raman spectroscopy was also employed to estimate the amount of the so-called interphase in the HDPE cast films. As a result, the interphase content was found to decrease by increasing the applied draw ratio. The origin of this dependency was suggested to be due to a coil–stretch transition during elongation flow and the subsequent disentanglement. On the other hand, remarkable differences were observed in the CH2 bending vibration features of the Raman spectra of the cast films which were correlated with the applied draw ratios and with the calculated crystalline orientation functions.

Ultra-high precision machining is proposed by externally actuating the work piece in linear motions in the X-Y plane and linear motion in the Z-axis. To solve the problems in the machining process such as nonlinearity and low repeatability positioning accuracy of machining tools in a larger scale, a novel platform for cutting tools in micro machining based on electrostatic linear micromotors and piezoelectric stack actuator system is presented.

Ethylene-vinyl alcohol copolymers (EVOH), with appropriate barriers and processability, can be chemically modified through vinyl alcohol units. Amides and polyamides based on condensation reactions of adipoyl chloride and hexamethylenediamine were grafted onto EVOH. Grafting was characterized by contact angle measurement, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), nuclear magnetic resonance spectroscopy (NMR) and scanning electron microscopy (SEM). Amide peaks at 3302 cm-1 corresponding to –NH bond stretching and the absorption of HN-CH2 at 7.8 ppm, were observed from ATR-FTIR and NMR, respectively, as a result of grafting. SEM showed the formation of amide structures as bundles, agglomerates and needle-like particles. Differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) showed considerable changes in onset of melt temperature, crystallinity and various transitions in grafted EVOH, showing an effective alteration in the physical properties compared with the virgin resin. Nylon grafted EVOH can be considered as a potential compatibilizer in polyethylene (PE)/polyamide blends via increasing interactions at the interface.

Laminated composite structures are vulnerable to failure when subjected to impact and vibration. The present work investigates the impact response of laminated composite structures filled with MR-fluid segments. The mathematical modelling of a composite plate is presented using finite element method with MATLAB® software to study the vibration response due to impact loads. A proof-of-the-concept experimental work has been set up in order to illustrate the performance and functionality of the MR-fluid on damping vibration for MR-laminated composite structures.

A trifunctional organo alkoxysilane (3-aminopropyl)triethoxysilane (γ-APS) has been used as reagent for the chemical modification of montmorillonite clay. Silane grafting was taken place in dry and hydrolyzing conditions. Silane grafted and pristine clay took part in interfacial polycondensation process to deposit a layer of nylon-66 onto the clay lamellae and therefore, enhance their affinity with nylon-66 matrix. Evidence of presence of grafted silane molecules and deposition of nylon-66 on clay particles were provided by Fourier transform-infrared, thermogravimetric analysis (TGA), and X-ray diffraction (XRD). Such modified clays and pristine clays were melt compounded with nylon-66. The structures of the resulting nylon composites were characterized using XRD and transmission electron microscopy and the results showed presence of both intercalation and exfoliation. TGA thermograms of nanocomposites indicated improved thermal stability upon the incorporation of silane grafted montmorillonite. Furthermore, differential scanning calorimetry scans showed that silane modified clays promoted crystallization in nanocomposites. Increase of storage modulus and depression of tan δ peak in nanocomposites in dynamical mechanical thermal analysis were observed. The rheological properties of nylon-66 and nanocomposites were also evaluated and differences in values of complex viscosity of samples were noticed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The aims of this study were to determine vertebral heart size (VHS) in stray cats and to compare different radiographic views. This study was performed on 50 adult stray cats. All cats were short-haired and non-obese and were considered to be healthy based on physical examination and electrocardiography. Left and right lateral, dorsoventral and ventrodorsal radiographs were taken. The long and short axes of the heart were measured in millimetres. The thoracic vertebral length spanned by each dimension was measured caudally from the fourth thoracic vertebra. Mean ± SD and the correlation coefficient between the measurements were calculated with standard statistical software. The sum of the long and short axes of the heart expressed as VHS was 7.3 ± 0.49 vertebrae in right lateral, 7.3 ± 0.55 vertebrae in left lateral, 7.5 ± 0.68 vertebrae in dorsoventral and 7.5 ± 0.53 vertebrae in ventrodorsal. The differences between right and left lateral as well as dorsoventral and ventrodorsal views were not significant ( P > 0.05). Absolute measurements and vertebral heart scale values were slightly smaller than those reported in the literature for mixed population of cats. It is, therefore, important to take the breed in to account.

Background: Despite the importance of self-management in epileptics, no instrument has been developed or validated in Iran. Since self-management is a multi-dimensional construct, having a valid and reliable instrument for measuring this compound construct is crucial. Objectives: This study aims to validate the Persian version of the self-management scale and provide a valid and reliable tool to measure self-management of patients with epilepsy. Patients and Methods: This is a methodological psychometric study. Construct , face and content validity was calculated on 200 samples after translation. Tool reliability was examined by using two methods: internal consistency and test-retest. Finally, the modified model was presented using exploratory factor analysis for the Iranian version of the tool. Results: The validity of all items was above 0.63 and their content validity indexes (0.81-1) were appropriate. Construct validity, exploratory and confirmatory factor analysis confirmed all the dimensions except for some safety and pharmacotherapy items. The overall tool reliability with internal consistency had alpha of 0.77. Conclusions: Persian version of the self-management scale for patients with epilepsy is valid and reliable to measure the dimensions of self-management in Iranian patients and it can be used to measure epileptics’ self-management. Further research on the safety of this tool is recommended.