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Copyright of International Journal of Engineering Transactions B: Applications is the property of International Journal of Engineering (IJE) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Statement of Problem: One of the factors affecting the degree of polymerization of light-cured composites is the type of light-curing unit used. In addition, physicomechanical properties of the composite resins depend on the degree of conversion and polymerization. Objectives: Since the type of initiator in new composite resins is not explained by manufacturers, this study is an attempt to compare the depth of hardening, with two LED and QTH light-curing units. Materials and Methods: Fifteen samples prepared from Gradia Direct and Filtek Z250, both of which being universal, were cured with QTH (Astralis 7) and LED (Bluephase C8) light-curing units. All the samples were molded in polyester resin and cut from the middle by a disk. The hardness of the cut area was evaluated at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5 and 4-mm depth intervals and also at the same interval as the width of the sample, with Vickers hardness machine, while the samples were placed in a darkroom. Data were statistically analyzed using one-way ANOVA, two-way ANOVA, t-test and post Hoc Tukey’s tests in SPSS, version 16. Results: Filtek Z250 was harder than Gradia Direct at all the depth with both light-curing units. The hardness of Filtek Z250 sample cured with Astralis 7 was higher than that cured with LED, but with Gradia Direct the LED unit resulted in higher hardness. Curing depth was not significantly different between the groups (p = 0.109). Conclusions: Vickers hardness number for both composites used in this study is in an acceptable range for clinical implications. The composites’ composition is important to be considered for selection of light unit. Based on the findings of the present study, LED did not present more curing depth compared with QTH.

The present research aims to investigate the two-phase air/water flow in a vertical pipe using an electrical resistance sensor and a high-speed camera. An electrical resistance sensor is designed and embedded in the inner wall of the tube. A flow pattern map is drawn at the height of 270 cm from the testbed inlet for 320 different phase velocities using a high-speed camera. By measuring the output voltage of the electrical resistance sensor and using the Maxwell relation, the volume fraction in bubbly and slug flow regimes are calculated for different phase velocities. The volume fraction values detected from the output signal of the electrical resistance sensor are compared with the results obtained from the high-speed camera images. The width of the output signal from the electrical resistance sensor indicates the length of the Taylor bubble. The output signal width is compared to the obtained Taylor bubble length from high-speed camera images, for several different velocities of the phases. It is noticed that at a constant velocity of the phases, the output signal width from the sensor is linearly related to the length of the Taylor bubble. The variations of the output signal width are plotted in terms of the ratio of the Taylor bubble length to the summation of air and water superficial velocities. By linear fitting of the available data, a novel equation is presented to calculate the Taylor bubble length in terms of the signal output from the electrical resistance sensor and the total superficial velocity of the phases. [ABSTRACT FROM AUTHOR]

Background and Objectives: Cadmium is a toxic metal which is widely used in industry. This metal exerts toxic effects on multiple organs, including nervous system. The aim of this study is to evaluate the effect of cadmium on weight and development of hippocampus in Wistar rat embryos and then determining whether L-carnitine, as an antioxidant, can protect hippocampus from the toxic effects.Methods: Female Wistar rats (250-300g) were used in this study. 24 hours after mating with male rats, the females were separated and their vaginal smears were examined for sperm detection. This day was considered as embryonic zero day. The female rats were divided into three groups: The control group which received no injection, the experimental group 1 which received 1mg/kg B.W cadmium and the experimental group 2 which received 1mg/kg B.W cadmium+500mg/kg B.W L-carnitin in days 7 and 10 of gestation. On day 17 of gestation, the animals were sacrificed by chloroform over dose and their embryos were removed surgically. The embryos were fixed in formalin 10% for 30 days, the weight of embryos were measured. Then tissue processing, sectioning and Hematoxylin-Eosin (H & M) staining were done. Some sections of hippocampus were evaluated using light microscope and MOTIC soft ware. Results: The weight of embryos were significantly decreased in experimental groups. This decrease was significantly greater in the Experimental group 2. The number of cells and thickness of hippocampus layers were decreased significantly just in the second group. Conclusion: These findings indicate that cadmium has teratogenic effects on embryo’s weight and development of hippocampus and at least a part of these effects may be inhibited by L-carnitine.

Aim; Autism is a pervasive developmental disorder Deficit; in sensory functions is one of the characteristics of people with autism, and usually these people show abnormality in processing and correct interpretation of auditory information. Also people with Autism show problems in communicating with others. This review article deals with the accurate understanding of Auditory processing skills of autistic children compared to normal children is done to clarify the auditory processing disorder in this group. Information & Methods This systematic review was conducted in articles published from 2002 to 2022 in the field of electrophysiological evaluations of auditory brainstem in autism spectrum disorder by searching Scopus, PubMed, Google Scholar, and Science Direct databases. Finding: Disorders were observed in the brainstem electrophysiological responses of patients with ASD compared to the normal group. The results of studies of auditory brainstem evoked responses with click stimuli showed an increase in wave V latency and I-V interpeak latency in ASD subjects compared to normal groups. Studies of brainstem evoked responses with speech stimuli also showed a decrease in amplitude and an increase in latency. Conclusion Auditory processing disorders in verbal and non-verbal stimuli in people with autism spectrum have been reported. Most studies show disorders in speech stimuli, which play a very important role in communicating. department [ABSTRACT FROM AUTHOR]

In this group article, part of the teaching of advanced dynamics course has been done in the form of group-based training projects. In this project, the mechanism of a spinning ride is designed and then engineering analyzes are performed on it. The system of this spinning ride must be designed in such a way that the absolute acceleration of the human head is equal to six times the acceleration of gravity. The most basic thing to do is conceptual design. Engineering analyzes such as dynamic analysis and motion simulation; finite element analysis is also performed to obtain natural frequencies and to determine the deformations caused by loading. After completing the above steps, information will be provided about materials and manufacturing processes. Due to the fact that this project was carried out in the form of a new method of learning advanced dynamics in the form of nine groups at Sharif University of Technology and the groups competed with each other, in the end, students were surveyed about the amount of learning from this method of teaching. [ABSTRACT FROM AUTHOR]

The multiscale multiphase flow contains both small-scale (dispersed phase) and large-scale (continuous phase) structures. Standard interface-averaging multiphase models are appropriate for the simulation of flows including small-scale structures. Standard interface-resolving multiphase models are commonly used for the simulation of flow regimes containing large-scale structures. The accurate simulation of different regimes has a crucial role to investigate the physics of multiphase flows. To cover the inability of standard models to simulate multiscale multiphase flows, various generalized hybrid models have been developed. The present research aims to present an LES-like approach to identify the large-scale structures by comparing the equivalent diameter of structures and the averaging length scale. The main difference between the presented model and the models available in the literature is the independency of the model to the thresholds of the local volume fraction to recognize the flow regime. The switching criterion is set based on the cell size and the physical phenomena including the break-up and coalescence mechanisms. To assess the capabilities of the presented multiscale model, four different benchmark cases including the bubble column, the impinging jet, the dam break, and the Rayleigh-Taylor instability are investigated. The physical behavior of the flow is considered as a reference and compared with numerical results. It is demonstrated that the present multifluid model is capable to capture the physical characteristics of both dispersed and segregated flow regimes, and it is a forward step to develop a generalized multiscale hybrid multiphase model. [ABSTRACT FROM AUTHOR]

A prevalent problem in pomegranate (Punica granatum L.) fruit is sunburn which reduces fruit quality. This study aimed to reduce the severity of sunburn during the fruit development of pomegranate by covering them with colored netted bags. Kaolin (5%) as a traditional treatment to reduce sunburn was used to compare the efficiency of noble and traditional techniques. The netted bags used were either white, green, yellow, gray or blue. This study was carried out on a commercial cultivar (Rababe-Neyriz) over a period of two successive years. The color of the netted bags affected the anthocyanin content of arils at harvest besides minimizing the levels of sunburn. Fruit of the control group were damaged notably (32.26%) by sunburn, compared to those covered with blue and white netted bags (0%). The highest amount of ascorbic acid and the minimum amount of anthocyanin were recorded in the fruit covered with blue netted bags. The lowest degree of aril whitening (discoloration of arils) was observed when fruit were covered with white bags. Covering the fruit with gray netted bags caused the highest antioxidant activity and the highest total phenolic content in the arils. Overall, covering fruit with netted bags is recommended to prevent sunburn and to enhance fruit quality. [ABSTRACT FROM AUTHOR]

This paper studies a B-spline algorithm for calculating the solution of the multi-term time-fractional diffusion equationsM-TT-FDEs. This model describes the diffusion prossing in the fluid mechanics and provides valuable predictions. The solution of the MTT-FDEs. is discretized by means of B-spline function based on the B-spline shape technique. It is verified that the proposed strategy is more efficient in terms of computational time and accuracy in domain. [ABSTRACT FROM AUTHOR]

The present study aims to propose a robust method to detect the damage severity and location of the structural elements, focusing on the data type and acquisition method and promoting the model updating tools. The novelty of this method lies in its rotational mode shape acquisition that provides valuable information on the damage. In this method, the damaged elements were indirectly identified by detecting the healthy elements and eliminating them from the search space. Moreover, this method could minimize the modal strain energy difference between the damaged reference model and the numerical model using an optimization algorithm. An improved genetic algorithm was then employed to perform the optimization task. In this study, four numerical and two experimental damage scenarios were applied to a simply supported beam to examine the performance of the proposed method. Data acquisition systems were implemented using vision-based and accelerometer-based methods. The results indicated that this method could accurately identify the location and severity of damage using only the first mode shape since the rotational mode shapes were more sensitive to damage than the vertical mode shapes. [ABSTRACT FROM AUTHOR]

In this part of the study, several benchmark problems are solved to evaluate the performance of the existing strain-based membrane elements, which were reviewed in the first part. This numerical evaluation provides a basis for comparison between these elements. Detailed discussions are offered after each benchmark problem. Based on the attained results, it is concluded that inclusion of drilling degrees of freedom and also utilization of higher-order assumed strain field result in higher accuracy of the elements. Moreover, it is evident that imposing the optimal criteria such as equilibrium and compatibility on the assumed strain field, in addition to reducing the number of degrees of freedom of the element, increases the convergence speed of the resulting strain-based finite elements. [ABSTRACT FROM AUTHOR]

Since the introduction of the finite element approach, as a numerical solution scheme for structural and solid mechanics applications, various formulation methodologies have been proposed. These ways offer different advantages and shortcomings. Among these techniques, the standard displacement-based approach has attracted more interest due to its straightforward scheme and generality. Investigators have proved that the other strategies, such as the force-based, hybrid, assumed stress, and assumed strain provides special advantages in comparison with the classic finite elements. For instance, the mentioned techniques are able to solve difficulties, like shear locking, shear parasitic error, mesh sensitivity, poor convergence, and rotational dependency. The main goal of this two-part study is to present a brief yet clear portrait of the basics and advantages of the direct strain-based method for development of high-performance plane finite elements. In this article, which is the first part of this study, assumptions and the basics of this method are introduced. Then, a detailed review of all the existing strain-based membrane elements is presented. Although the strain formulation is applicable for different types of structures, most of the existing elements pertain to the plane structures. The second part of this study deals with the application and performance of the reviewed elements in the analysis of plane stress/strain problems. [ABSTRACT FROM AUTHOR]