Search

Biosynthesizing conjugated linoleic acid (CLA) using food processing by-products offers a practical and efficient method for producing this valuable compound, delivering health benefits, promoting sustainability, and providing economic advantages. Here, we optimized the fermentation conditions for in situ biosynthesis of CLA using Bacillus coagulans IBRC-M 10807, with grapeseed oil by-product providing the linoleic acid precursor, focusing on temperature, pH, incubation time, concentrations of grapeseed oil and yeast extract. The total CLA was measured using a UV-Vis spectrophotometer at 233 nm, and the concentration was evaluated using a standard curve of conjugated linoleic acid. To analyze the isomers and identify the functional groups of biosynthesized CLA, gas chromatography (GC) and Fourier-transform infrared spectroscopy (FTIR) were used, respectively. The results indicated that the maximum amount of CLA production was 225.37 ± 0.74 μg/mL, obtained under optimal conditions: an initial pH of 6.8, a temperature of 44.8°C, an incubation time of 48 h, a grapeseed oil concentration of 1,000 μg/mL, and a yeast extract concentration of 3.88%. Characterization of the produced CLA revealed two main isomers--CLA 1: c-9, t-11 C18:2, and CLA 2: t-10, c-12 C18:2 methyl esters. These results suggest that B. coagulans has high potential to produce CLA as a bioactive compound, offering an excellent opportunity for use in various industries, including nutraceuticals, foods, pharmaceuticals, cosmetics, and animal feeds. [ABSTRACT FROM AUTHOR]

In recent decades, the concept of a knowledge-based city has been proposed as one of the most important concepts in urban planning. The present study evaluates the ability to localize urban planning indicators in the city of Urmia and determine the desirability of knowledge-based city indicators to provide coherent policies and strategies to achieve sustainable development and a knowledge-based city. Localization is the adaptation of global patterns and methods of development and planning to the internal conditions of the local community. In order to collect data from documents and library studies, experts' opinions have been used by the Delphi method. Then, indicators related to local urban planning and knowledge-based city were extracted. The present study's statistical population is 20 specialists and experts related to the research topic through the survey method. In order to analyze the research data, a one-sample t-test was used to assess the ability to localize aspects of urban planning in the city of Urmia. In order to investigate the degree of correlation and factor load of each urban planning indicator, confirmatory factor analysis was used. Using the Swara technique, the desirability and knowledge-based city indicators' priority level has been evaluated and analyzed. The research results indicate that each of the economic, social, physical, environmental, and managerial aspects of urban planning can be localized in the city of Urmia. Moreover, the situation of Urmia in some aspects is in a situation of incompatibility in terms of the feasibility of the knowledge-based city's policies. In order to improve the current situation and achieve the desired goals, suggestions have been made in various aspects. [ABSTRACT FROM AUTHOR]

Electroactive polymers (EAP) can alter and change their shape when subjected to an electric field, they have been investigated for a variety of purposes including smart drug delivery and artificial muscles. However, approaches to design electroactive hydrogel structures can be hindered by low polymeric conductivity, which then requires high electrical input to induce movement and results in low cellular viability. Our purpose in this study, was to reduce the input voltage required for movement by layering electroactive PEGDA:Acrylic acid (PEGDA:AA) with poly(ethylene glycol) diacrylate (PEGDA) modified with a conductive nanocomposite of colloidal poly(3,4 ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) and graphene oxide (GO). In this study PEDOT:PSS/GO was a flexible electrode that stimulated the PEGDA:AA. The multilayered hydrogel was evaluated for angular movement, electrical properties, and biocompatibility with C2C12 myoblast cells. The data showed that increasing the PEDOT:PSS/GO in the hydrogel decreased the conductivity, potentially due to the presence of GO. The addition of PEDOT:PSS/GO increased scaffold movement compared with PEGDA:AA alone when stimulated at 1 V. Fewer scaffolds displayed significantly more movement with increased voltage, but the 10% PEDOT:PSS/GO group experienced more movement at each tested voltage. C2C12 cells on the 10% PEDOT:PSS/GO were more metabolically active than cells on scaffolds with increased concentrations of PEDOT:PSS/GO. This work is an initial step in creating biocompatible scaffolds capable of actuation for tissue engineering. [ABSTRACT FROM AUTHOR]

Today's cities are increasing their space zones while becoming more vulnerable to natural disasters and man-made threats. The initial evaluation of the resilience of city systems is of great importance and helps develop policies and measures that would improve resilience. This paper, using a descriptive–analytic method, defines the characteristics of a resilient city, and natural disasters are addressed. At the same time, the process of reaching a resilient city is investigated. Then, the indicators of resilience have been defined in pillars of ecologic, physiological, social, economic, and managerial–institutional dimensions for the evaluation of a resilient city in Iran. As the sample of the study, the indicators of the study were evaluated in the city of Sanandaj and prioritized in the network analysis process (ANP). The results of this analysis showed that zones one and two, respectively, were the weakest parts regarding urban resilience. In order to move toward a resilient city, future investments should go beyond financial investment and technical solutions and consider human and community development, as well as institutional capacity and inter-organizational cooperation. [ABSTRACT FROM AUTHOR]

Hydrogels have been used for many applications in tissue engineering and regenerative medicine due to their versatile material properties and similarities to the native extracellular matrix. Poly (ethylene glycol) diacrylate (PEGDA) is an ionic electroactive polymer (EAP), a material that responds to an electric field with a change in size or shape while in an ionic solution, that may be used in the development of hydrogels. In this study, we have investigated a positively charged EAP that can bend without the need of external ions. PEGDA was modified with the positively charged molecule 2‐(methacryloyloxy)ethyl‐trimethylammonium chloride (MAETAC) to provide its own positive ions. This hydrogel was then characterized and optimized for bending and cellular biocompatibility with C2C12 mouse myoblast cells. Studies show that the polymer responds to an electric field and supports C2C12 viability. [ABSTRACT FROM AUTHOR]

Today, the use of waste tires mixed with soil has been expanded in various geotechnical projects to absorb and reduce the vibration caused by seismic and dynamic loads. Therefore, the objective of this work was to evaluate the dynamic properties of such mixtures prior to practical applications. To this reason, 1-g shaking table tests were carried out, and the effects of important parameter like loading frequency on the dynamic behavior of mixtures were investigated. Tire powders were added to the sand with 5%, 10%, 15% and 20% in gravimetric basis and with a relative density of zero were subjected to sinusoidal loading at frequencies of 0.5, 1, 2, 3, 5, 7 and 9 Hz and input acceleration of 0.1 g and 0.3 g. The results showed that in all cases, the increase in frequency in the same cycles increased the shear modulus and the damping ratio. Also, with increasing shear strain, the shear modulus of the mixture decreased, but the damping ratio increased. On the other hand, by increasing the tire powder, the value of the shear modulus is reduced, but the amount of damping ratio is increased. [ABSTRACT FROM AUTHOR]