Although its wide utilization in microbial cultures, the one factor-at-a-time method, failed to find the true optimum, this is due to the interaction between optimized parameters which is not taken into account. Therefore, in order to find the true optimum conditions, it is necessary to repeat the one factor-at-a-time method in many sequential experimental runs, which is extremely time-consuming and expensive for many variables. This work is an attempt to enhance bioactive yellow pigment production by Streptomyces thinghirensis based on a statistical design. The yellow pigment demonstrated inhibitory effects against Escherichia coli and Staphylococcus aureus and was characterized by UV-vis spectroscopy which showed lambda maximum of 449. The FTIR and GC-MS analysis showed that the colorings in this type of product are due to the presence of chromo peptides. Furthermore, the GC-MS measurement determined the presence of 4 compounds, as it gave 4 different retention times within this yellow pigment, but with different percentages, except for the compound BHT when the retention time was 17.86 minutes. Starch casein broth (SCB) was selected as an optimized medium for yellow pigment production. The optimization process was first started with one factor at time method, revealing that maltose and casein were the best carbon and nitrogen sources. Response surface methodology based on central composite design was conducted to obtain the optimal combinations of maltose and casein concentrations, pH, and inoculum size for maximum production of yellow pigment. The results showed that casein was the most effective parameter with F-value 393.1 and the model exhibited good fitting with a correlation coefficient of 0.946. Moreover, the actual maximum yellow pigment product 0.80 nm which aggregated with a predicted value 0.835 nm at maltose concentration 8 g/L, casein 5 g/L, KNO3 0.01 g/L, pH 6 and inoculum size 5%.
This work deals with the effect of adding aluminum nanoparticles on the mechanical properties, micro-hardness and porosity of memory-shape alloys (Cu-Al-Ni). These alloys have wide applications in various industrial fields such as (high damping compounds and self-lubricating applications). The samples are manufactured using the powder metallurgy method, which involved pressing in only one direction and sintered in a furnace surrounded by an inert gas. Four percentages (0%, 5%, 10%, and 15%) of aluminum nanoparticles were fabricated, which depended on the weight of aluminum powder (13%) in the sample under study. To find out which phase is responsible for the reliability of the formation of this type of alloy and its porosity, X-ray diffr
... Show MoreIntroduction: Carrier-based gutta-percha is an effective method of root canal obturation creating a 3-dimensional filling; however, retrieval of the plastic carrier is relatively difficult, particularly with smaller sizes. The purpose of this study was to develop composite carriers consisting of polyethylene (PE), hydroxyapatite (HA), and strontium oxide (SrO) for carrier-based root canal obturation. Methods: Composite fibers of HA, PE, and SrO were fabricated in the shape of a carrier for delivering gutta-percha (GP) using a melt-extrusion process. The fibers were characterized using infrared spectroscopy and the thermal properties determined using differential scanning calorimetry. The elastic modulus and tensile strength tests were dete
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Social networking sites have become very popular since the beginning of the current decade and have become linked to our daily life. We follow the news, Analyses and opinions on the one issue in a way that attracts millions of users and the number grows every secon On Twitter, one of the most important social networking sites, all social groups rushed from the president to the last citizen to open accounts when they found themselves forced to do so . During the recent Gulf crisis, Twitter was buzzing with Twitter, which achieved the largest circulation globally. Instead of serving the issue and directing it to serve the Arab interest, most of the publications were on th |
The present research deals with the study of the symmetries of the design of interior spaces in fast food restaurants in terms of formality as it is an important element and plays a direct role in the spatial configuration, which is designed in both of its performance, aesthetic and expressive aspects. Since the choice of shapes is a complex subject that has many aspects imposed by functional and aesthetic correlations, the problem of the research is represented by the following question: (To what extent can the symmetries of the interior design be used in the spaces of fast food restaurants?)
The research acquires its importance by contributing to the addition of knowledge to researchers, scholars, companies and the specialized publ
out of the familiar context in interior design and surprise the user with a new design event that is emotionally caressing psychologically and physically alluring which is not an easy matter in a time where knowledge is within everyone's reach, and the reasons for achieving the design event became a creative evaluation by the user, not only at the formative level, but also at the space level as a design event that is dealt with by a causal and not inevitable manner, Achieving the event of surprise in designing interior spaces has proved to be a great challenge to the interior designer's abilities to think of out of the ordinary and bypassing the user's cognitive reference as an experience to achieve the emotions of surprise, suspense, attra
... Show MoreWell integrity is a vital feature that should be upheld into the lifespan of the well, and one constituent of which casing, necessity to be capable to endure all the interior and outside loads. The casing, through its two basic essentials: casing design and casing depth adjustment, are fundamental to a unique wellbore that plays an important role in well integrity. Casing set depths are determined based on fracturing pressure and pore pressure in the well and can usually be obtained from well-specific information. Based on the analyzes using the improved techniques in this study, the following special proposition can be projected: The selection of the first class and materials must be done correctly and accurately in accordance with the
... Show MoreWell integrity is a vital feature that should be upheld into the lifespan of the well, and one constituent of which casing, necessity to be capable to endure all the interior and outside loads. The casing, through its two basic essentials: casing design and casing depth adjustment, are fundamental to a unique wellbore that plays an important role in well integrity. Casing set depths are determined based on fracturing pressure and pore pressure in the well and can usually be obtained from well-specific information. Based on the analyzes using the improved techniques in this study, the following special proposition can be projected: The selection of the first class and materials must be done correctly and accurately in accordance with
... Show MoreThere are many diseases that affect the arteries, especially those related to their elasticity and stiffness, and they can be guessed by estimating and calculating the modulus of elasticity. Hence, the accurate calculation of the elastic modulus leads to an accurate assessment of these diseases, especially in their early stages, which can contribute to the treatment of these diseases early. Most of the calculations used the one-dimensional (1D) modulus of elasticity. From a mechanical point of view, the stresses to which the artery is subjected are not one-dimensional, but three-dimensional. Therefore, estimating at least a two-dimensional (2D) modulus of elasticity will necessarily be more accurate. To the knowledge of researchers, there i
... Show MoreStroke is the second largest cause of death worldwide and one of the most common causes of disability. However, several approaches have been proposed to deal with stroke patient rehabilitation like robotic devices and virtual reality systems, researchers have found that the brain-computer interfaces (BCI) approaches can provide better results. In this study, the electroencephalography (EEG) dataset from post-stroke patients were investigated to identify the effects of the motor imagery (MI)-based BCI therapy by investigating sensorimotor areas using frequency and time-domain features and to select particular methods that help in enhancing the MI-based BCI systems for stroke patients using EEG signal processing. Therefore, to detect
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