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In this study, Virtual Reality (VR) was employed in an English course intended to promote oral presentation skills in Iranian academia, and the possible impact of the course on learners’ self-efficacy regarding presenting, Foreign Language Anxiety (FLA), and speaking skills was investigated. Eight participants attended a 6-session course, and practiced academic oral presentation in a virtually simulated environment. Prior to the course, semi-structured interviews were administered; in addition, participants’ weekly reflection notes and self-assessments were gathered throughout the course. Moreover, post-course semi-structured interviews and written follow-up interviews were conducted afterward. The findings revealed that the learners reported higher levels of self-efficacy regarding presenting after the course, due to a perceived improvement in their presenting style, as well as their presentation content and slides. Additionally, the course had contributed to lowering the learners’ FLA due to presence in the Immersive Learning Environment (ILE), ample practice opportunities, and collaborative avatar interactions. Moreover, the learners mentioned that the course had helped them to improve their speaking skills due to academic vocabulary expansion, pronunciation enhancement, fluency upgrade, and grammatical adjustment. The findings can provide insights for language educators with regard to the use of virtual reality for simultaneously fostering language and academic skills, as well as facilitating internationalization in higher education.

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Nine wild olive accessions collected from the Golestan province, the North of Iran, were screened under greenhouse conditions for their resistance to Verticillium wilt. Plants of the highly susceptible cv. ‘Zard’, frequently used as a local cultivar, were also included in this test. Nine-month-old nursery olive plants were inoculated by root-dip method with defoliating (VCG1, D) and non-defoliating (VCG4B, ND) isolates of Verticillium dahliae, both obtained from diseased olives in Golestan province. Resistance was evaluated by assessing symptom severity using 0-4 rating scale and estimating the area under disease progress curves. The percentage of plants killed, final mean severity of symptoms, frequency of V. dahliae reisolation from olive xylem, dry weight of new green leaves and shoots and total phenol content in root tissues were used as additional parameters. The results showed that seven of the nine wild olive accessions were highly resistant to D and ND isolates of V. dahliae. A second group of wild olive accessions (P4 and P7) were classified as moderately resistant and resistant to D and ND isolates of V. dahliae, respectively. Phenol content was significantly higher in highly resistant plants and correlation coefficient analyses revealed a negative relation between disease severity and root total phenol contents. Dendrogram of wild olive accessions and ‘Zard’ cultivar based on all parameters represented two main clusters, major and minor. Minor cluster comprised only two wild olive accessions and ‘Zard’ cultivar. Major cluster could be divided into two groups, I and II, showed a highly resistance reaction to pathotypes of V. dahliae.

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Abstract: In the papers published on compressible fluid using Pseudo Bond Graph approach, isentropic flow is assumed. However in a converging- diverging nozzle, for a specific pressure ratio, the assumption of isentropic flow is invalid. For the purpose of considering normal shock effects, this paper introduces a new field (NIKE-field) to the pseudo bond graph. The output of the new field can be also used to determine normal shock position and to extract momentum equation as well. In the following, the methodology developed in this paper has been applied a simple pedagogic example. Simulation result is validated by comparison with the analytical result. As the new field can be modeled non-isentropic flow, it can be used to for modeling rockets motors and thrusters in transient state. One of another advantage of new field (NIKE-field) is that it can be easily used in many software applications like MS1, SYMBOLS2000 and 20SIM®; therefore, With regard to the systematic derivation of a mathematical model from a bond graph in these softwares, there is no need to derive any state equations and their solutions.

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Side weir is one of the most important structures in flood treatment projects that are designed provided the main channel bed is rigid. However, in the most practical channels, the main channel bed is movable and the changes in bed can produce wavelike patterns known as bed forms and another additional effect of side weir on bed forms is that it causes an aggradation of sediment particles in front of itself. These two products of using side weir in movable beds cause an additional bed resistance in comparison with the state that there isn’t any weir on sidewall of main channel and so the flow level with using side weir will rise subsequently and this means more diversion ratio. Thus, In order to study the effect of side weir hydraulic and geometric properties through Froude Numbers, diversion discharge ratios and flow depths on bed forms and its effect on design conditions, the present research work is carried out. A set of 9 experiments were conducted in a flume with dimensions of 0.85 m width, 0.40 m height and 10 m length on a mobile bed having median sediment particle size of 0.23 mm running with side weirs of crest lengths of 20, 40 and 60 cm . In addition a set of 3 experiments without using a weir were considered as bench mark experiments for comparison purposes. After running a determined flow in flume regarding with the bed profiles should reach a balance it was stopped after 1-3 hours. The bed topography at the end of each experimental run was recorded using automatic bed profiler in a length of 220 cm of main channel. This topography was recorded in a net of points that were distributed in a distance of 5 cm in length and 3 cm in width. The dimensions of bed forms were then determined using the well-known crest-through method. The results indicated that the effect of flow depth, discharge, and diversion ratio on bed form dimensions are significant and increasing these parameters cause an increasing influence on bed form dimensions. In this study 4 equations are suggested that both of them are for bench mark experiments and two others are for main experiment. The coefficients of these relations were determined by Solver Add In program in Excel with using 80 percent of data that were selected in chance and then they were verified with using remaining 20 percent of data. Verification of relations also illustrated that for both length and width of bed form in main experiments the maximum error of related equations is 50 percent and maximum error of relations for bench mark experiments is 30 percent. Analyzing these relations revealed an important influence of applying side weirs on lateral variation of bed form dimensions in the main channel so that it is indicated that bed form length and height near side weir will increase up to 70 and 2 percent of channel width, respectively, in comparison with the experiments that side weir is not used.

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Synthetic biomaterials are currently used as bone graft substitutes to treat bone disorders. Based on biomechanical properties, these biomaterials are selected to engineer bioactive and bioresorbable scaffolds that increase tissue ingrowth. These porous scaffolds play an important role in new bone formation and vascularization with the ability to incorporate genes, drugs, growth factors, and stem cells. This review focuses on recent advances on bioactive glass materials for bone regeneration. Despite inherent brittleness, bioactive glasses have many promising characteristics for bone engineering scaffolds. Compared to silicate bioactive glasses, borate and borosilicate have the ability to enhance new bone formation .These materials have controllable degradation rates that closely match new bone formation. Interestingly, bioactive glasses can be doped with elements such as Cu, Zn, and Sr, which are advantageous for healthy bone growth. Although bioactive glasses have been examined in detail for bone repair, few investigations have been performed on their applications for repair of soft tissues. A recent work has shown bioactive glass has the ability to promote angiogenesis for healing of soft tissue wounds.
In this review, we highlight current advances in the use of bioactive glass materials and their conversion into scaffolds with the essential anatomical shape. Methods used to manipulate the materials’ structures in bone tissue engineering applications and growth factors involved in bone regeneration will be briefly discussed.

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The purpose of this study was to evaluate the effect of sumac (Rhus coriaria L.) administration on the growth performance, immune response, and haematological parameters of rainbow trout (Oncorhynchus mykiss). Rainbow trout juveniles with an initial weight of 38±2.65 g were allocated into 12 tanks at a density of 15 fish per tank. Fish were fed four experimental diets containing 0% (as control diet), 0.5%, 2%, and 5% sumac-supplementation for 56 days. After the feeding trial, fish were challenged with Yersinia ruckeri, and survival rate was calculated for 15 days. Sumac diet significantly increased resistance to the pathogen and led to the control of infection in rainbow trout without changing weight. The leukocyte (WBC) and erythrocyte (RBC), lymphocyte, monocyte, and neutrophil value was significantly higher in fish that were fed a sumac-supplemented diet when compared with the control. Serum lysozyme, and alternative complement pathway haemolytic activity (ACH50) as well as the hepatic expression of TNF-α and IL-1b were recorded to be the highest in fish fed 2% and 5% sumac-supplement. Meanwhile, mRNA expression levels of IL-10 significantly decreased in fish fed 5% sumac supplementation for 56 days. These results suggest that sumac administration, especially 2% and 5%, may effectively enhance the immune system, resistance to the pathogen, and hematopoiesis in rainbow trout.