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Background: Klinefelter syndrome (KS) is the most prevalent sex-chromosome aberration and the leading genetic cause of male hypogonadism. This chromosomal anomaly results in male hypergonadotropic hypogonadism, androgen deficiency, impaired spermatogenesis, and cognitive impairment. On the other hand holoprosencephaly (HPE) is a complex developmental disorder that represents a profound malformation of the human brain, characterized by the failure of midline cleavage of the prosencephalon into the right and left hemispheres. Case Report: The study presents a unique clinical scenario involving the co-occurrence of alobar holoprosencephaly (HPE) and Klinefelter syndrome (KS) in a term male fetus born to a healthy couple with uneventful prenatal ultrasound studies. While Klinefelter syndrome is known for its chromosomal aberrations, the simultaneous presence of HPE raises intriguing questions regarding the potential association between KS and cerebral malformations. Conclusion: This case highlights the importance of further research to explore the underlying mechanisms and implications of this rare intersection, shedding light on previously uncharted territory in the realm of genetic and neurodevelopmental disorders. [ABSTRACT FROM AUTHOR]

Commercially pure titanium (CP-Ti) due to excellent biocompatibility and high specific strength is known as a metallic biomaterial and is widely utilized in medical applications as implant material. Because of low strength of CP-Ti as compared to other bio-metals, it has been proved in literatures that applying equal channel angular pressing (ECAP) process can be useful to enhancement of mechanical and metallurgical properties of CP-Ti by improvement of initial microstructure to ultrafine grained (UFG). Implant in human body is attacked from cyclic fatigue loads and corrosion, simultaneous. Hence, aim of this study is examination of corrosion-fatigue resistance of CP-Ti before and after introducing ECAP in simulated body fluid (SBF) as a saline solution close to blood plasma. In this study, multi-pass ECAP is conducted on CP-Ti at room temperature and then the axial fatigue test is performed in SBF environment with temperature 37 °C. The comparison of stress-cycle curves demonstrated that corrosion-fatigue resistance of ECAPed CP-Ti is extremely higher than initial annealed one. Moreover, it was observed that by increasing the pass number of ECAP, corrosion-fatigue resistance improves significantly. Furthermore, these results are compared to fatigue behavior of CP-Ti in air environment. The results show that corrosion-fatigue resistance of unECAPed and ECAPed CP-Ti in SBF is slightly lower than fatigue ones in air. According to the results of this experimental research, it is concluded that UFG CP-Ti has an awesome corrosion-fatigue resistance in human body and it is very suitable for utilizing as material of implants. [ABSTRACT FROM AUTHOR]

In the analysis of contact mechanics problems, determination of stress field in mechanical elements is essential. Between the stress components the von Mises stress is more important, because it is used in the investigation of yield criteria and fatigue fracture of elements. The aim of this study is to present formulas for determining the magnitude and position of maximum von Mises stress. For this purpose, the effect of various material properties, element geometries and loading conditions on these two parameters are investigated. By applying Hertzian contact stress and von Mises relations, the magnitude and position of maximum von Mises stress are determined. The von Mises stress is assumed to be a function of material properties, geometry of the element and loading conditions and finally two formulas are presented for the calculation of the magnitude and position of maximum von Mises stress. The results of these presented formulas are in close agreement with the literature. The error is less than 1% for depth prediction and less than 6% for stress value prediction, which confirms the accuracy of the presented formulas. [ABSTRACT FROM AUTHOR]

In this study, the flow-forming process for fabricating seamless thin-wall tubes is experimentally investigated on a commercially pure titanium sample. For this purpose, the influence of three processing parameters including feed rate, mandrel revolution, and thickness reduction is studied on the surface quality and geometrical accuracy of flow-formed tube. It is found that the feed rate increment results in more longitudinal displacement of the roller on the tube sample. This intern results in, more area of the material to be in contact with the roller during the tube revolution; hence, higher tube surface roughness. Also, surface finish and dimensional precision of spun tube are lessened by increment of the mandrel revolution due to the intensification of machine vibration. Additionally, increased reduction of wall thickness leads to the enlargement of diametral growth and the loss of roundness. Also, it will increase the resistance of the material flow, which results in the wave creation at the tube surface, thereby decreasing the surface quality of the spun sample. [ABSTRACT FROM AUTHOR]

Shear walls are one of the important structural elements for bearing loads imposed on buildings due to winds and earthquakes. Composite shear walls with high lateral resistance, and high energy dissipation capacity are considered as a lateral load system in such buildings. In this paper, a composite shear wall consisting of steel faceplates, infill concrete and tie bars which tied steel faceplates together, and concrete filled steel tubular (CFST) as boundary columns, was modeled numerically. Test results were compared with the existing experimental results in order to validate the proposed numerical model. Then, the effects of some parameters on the behavior of the composite shear wall were studied; so, the diameter and spacing of tie bars, thickness and compressive strength of infill concrete, thickness of steel faceplates, and the effect of strengthening the bottom region of the wall were considered. The seismic behavior of the modeled composite shear wall was evaluated in terms of stiffness, ductility, lateral strength, and energy dissipation capacity. The results of the study showed that the diameter of tie bars had a trivial effect on the performance of the composite shear wall, but increasing the tie bars spacing decreased ductility. Studying the effect of infill concrete thickness, concrete compressive strength, and thickness of steel faceplates also showed that the main role of infill concrete was to prevent buckling of steel faceplates. Also, by strengthening the bottom region of the wall, as long as the strengthened part did not provide a support performance for the upper part, the behavior of the composite shear wall was improved; otherwise, ductility of the wall could be reduced severely. [ABSTRACT FROM AUTHOR]

In the present study, the two-layer sheet made of commercially pure copper (CP-Cu) and 304 stainless steel (SS-304) was fabricated by using explosive welding process and then was formed in U-shape bending process. In the study, the load was analyzed and effect of parameters such as punch tip radius, sheet thickness, friction coefficient, and mechanical properties on spring back of the two-layer sheet was investigated using experiments and finite element simulation. The results of this research show that, by increasing the strength and modulus of elasticity of material, thickness of sheet, the friction coefficient between die wall and sheet and reducing the punch tip radius, the spring back amount of sheet decreases. Moreover, the effect of mechanical properties of steel and increasing its thickness on the spring back reduction is more than the copper in two-layer metallic sheet. [ABSTRACT FROM AUTHOR]

Günespän-e Pätappeh is located 30 km to the southeast of the modem town of Malayer in Hamadan Province, 1 km away from the Kalän Dam. The site was excavated during six seasons as part of the archaeological salvage project inside the dam reservoir. The Islamic, Parthian, Achaemenid, Median and Bronze Age remains discovered in the excavations show that GQnespän was an important site in the Zagros Mountains. Most important, however, is the discovery during the fourth and fifth seasons of excavation of a fortified Median building showing close similarities to other Median architecture at nearby Nush-i Jan, Godin and Baba Jan. This newly uncovered structure sheds new light on the Median presence in western Iran. [ABSTRACT FROM AUTHOR]

Equal channel angular pressing is one of the most effective severe plastic deformation processes for fabrication of ultrafine grained or even nanostructured materials. Among the metallic biomaterials, commercially pure titanium exhibits the best mechanical properties, compared with other alloys. In this study, the effect of work-piece cross section on the mechanical properties of commercially pure titanium produced by this process has been investigated. The work-pieces in two types of cross section (square and circular) are pressed one pass in the square channel with angle 120° at room temperature and effects of cross section on the forming load, grain size, hardness and strength were studied. Finite element simulation using the ABAQUS software has been performed for forecasting the forming load, equivalent plastic strain and investigation of effects of geometry parameters of die channel on these. The simulation results show good agreement with experimental results. Through analysis of results, it is found that using the workpiece with circular cross section at equal channel angular pressing process not only decreased the required pressing load, but also significantly improved the mechanical properties of the materials such as hardness and strength as compared to using the work-piece with square cross section. [ABSTRACT FROM AUTHOR]

Zar Bolagh is located in the north of Qom province, central Iran. The site is known for its stone structure, which after its abandonment was deliberately filled with stone and gravel, similarly to Nush-i Jan, before finally being entirely covered by two thick stone and mud brick walls founded by mortar. In the winter of 2006, and under Malekzadeh's supervision, Zar Bolagh was investigated. During the course of excavation the team found valuable architectural elements comparable with other religious monuments in central Iran. This paper presents some preliminary results from the first season of excavation in Zar Bolagh, consisting of cemetery data and architectural remains. According to the pottery assemblage sequence this site can be dated to as early as the Late Iron Age. [ABSTRACT FROM AUTHOR]

• This research presents a meticulously derived mathematical formulation for calculating BSI stiffness, which is then validated through experimental data obtained from a novel laboratory test procedure. The main highlighted points of the current research are listed as follows: • This study involved the development of a closed-form formulation of (Ballast Shear Interlocking) BSI stiffness by considering how loads are distributed using pyramid cones. Using pyramid distribution theory on ballast layer, it is mathematically leaded to a closed-form expression for the BSI stiffness. Consequently, the shear interlocking stiffness of the ballast (K w) can be calculated by following equation: K w = 2 t g α (l e + 2 h b t g α) E b • A novel test setup is provided to determine the normal shear stiffness of ballast in compatible with track behavior due to vertical loading. As shown in belo figure, a vertical shear ballast box is used for determining the normal shear stiffness of the ballast. The suggested formulation of BSI stiffness aligns with the proposed laboratory configuration for assessing the normal shear interlocking that occurs between ballast aggregates. • A multi-layer track simulation was then conducted to investigate the sensitivity of BSI to various mechanical and geometric characteristics of the train-track interaction system. To study the impact of different mechanical and geometric properties and loading features on BSI stiffness, a finite element simulation was conducted using the shear interlocking stiffness formulation presented in this study. A sensitivity analysis was carried out to examine various parameters that affect BSI stiffness. The interaction among ballast particles, known as ballast shear interlocking (BSI), significantly influences the dynamic responses of railway track. This research presents a meticulously derived mathematical formulation for calculating BSI stiffness, which is then validated through experimental data obtained from a novel laboratory test procedure. The accuracy of the BSI formulation is demonstrated by its successful prediction of BSI properties in laboratory tests. Additionally, a numerical layered model is introduced to evaluate the sensitivity of the proposed formula to the mechanical and dynamic attributes of the ballasted track. This model highlights the resilience of tracks and emphasizes the critical role of BSI effects in railway track design, offering insights into parameters affecting track behavior. The study comprehensively explores ballast behavior, emphasizing the importance of BSI in track resiliency and advocating for its precise consideration in railway track design, modeling, and maintenance to ensure operational safety and efficiency. The developed methodology not only enhances the modeling of ballasted railway tracks as multi-layer systems but also advances the assessment of shear interlocking effects through laboratory testing. [ABSTRACT FROM AUTHOR]