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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]

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]