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ABSTRACT Given the potential for rapid progression and significant morbidity, clinicians should maintain a high index of suspicion for OAS in patients with HZO who present with neurological symptoms such as ophthalmoplegia, ptosis, and sensory loss.

Recent developments in technology have affected various aspects of human life, including education. These technological advancements have resulted in the introduction of new trends in teaching methodology. These trends include pure online instruction, mixed online and face-to-face instruction (blended), etc. In order to identify the efficacy of such kinds of instruction in comparison with traditional methods, this quasi-experimental study was conducted to explore the effects of virtual vs. blended-language instruction on the development of listening and reading skills by Iranian intermediate EFL learners. To achieve this goal, 60 intermediate EFL learners were selected to participate in two experimental (virtual and blended) and one control (traditional face-to-face) groups. After the provision of the treatments in experimental (reading and listening through virtual and blended methods of instruction) and control (reading and listening through traditional method) groups, a post-test was conducted to measure the attainment of the participants in each language skill. The results revealed that both virtual and blended methods of instruction could lead to better reading and listening performances. However, the difference between the effect of each treatment was more tangible in one skill scores (reading in the virtual group and listening in the blended group). The point worth noting is that the blended group could significantly outperform the other two groups. Comparing the results of all post-tests in reading and listening, it was revealed that blended instruction could result in better reading and listening; however, reading skill was more affected due to the higher mean difference between pre-test and post-test scores. This study has some implications for language teachers in taking advantage of technology in education in a balance with their traditional styles of teaching.

The advent of 3D printing has transformed manufacturing. However, extending the library of materials to improve 3D printing quality remains a challenge. Defects can occur when printing parameters like print speed and temperature are chosen incorrectly. These can cause structural or dimensional issues in the final product. This review investigates closed‐loop artificial intelligence‐augmented additive manufacturing (AI2AM) technology that integrates AI‐based monitoring, automation, and optimization of printing parameters and processes. AI2AM uses AI to improve defect detection and prevention, improving additive manufacturing quality and efficiency. This article explores generic 3D printing processes and issues using existing research and developments. Next, it focuses on fused deposition modeling (FDM) printers and reviews their parameters and issues. The current remedies developed for defect detection and monitoring in FDM 3D printers are presented. Then, the article investigates AI‐based 3D printing monitoring, closed‐loop feedback systems, and parameter optimization development. Finally, closed‐loop 3D printing challenges and future directions are discussed. AI‐based systems detect and correct 3D printing failures, enabling current printers to operate within optimal conditions and minimizing the risk of defects or failures, which in turn leads to more sustainable manufacturing with minimum waste and extending the library of materials.

This study focused on a modified Fused Deposition Modeling (FDM) 3D printing method, specifically the direct pellet printing of a propylene-based thermoplastic elastomer, Vistamaxx™ 6202, to address challenges like printability and weak mechanical properties. The main objective was optimizing printing parameters and investigating their impact on the mechanical properties. The Taguchi method was used to design the experiments, reducing the required experiments and optimizing printing parameters to maximize desired properties. Three influential parameters were chosen, each changing to three levels. By employing the Taguchi method, the number of experiments decreased from 27 full factorials to 9. Regression models were created through analysis of variance (ANOVA) and verified by additional experiments. Tensile tests were performed according to the ASTM D638 standard. SEM imaging was used to assess interlayer adhesion and structural integrity. The results demonstrated satisfactory interlayer adhesion and structural integrity of the printed samples. Notably, the printed thermoplastic elastomers achieved significant stretchability, reaching up to 5921.3%. The tensile strength was 5.22 MPa, with a tensile modulus of 1.7 MPa. The effect of each parameter and their contribution percentage to the tensile strength, elongation, and elastic modulus were obtained from the variance analysis.

Considering wide applications of Additive Manufacturing (AM), profound knowledge on the mechanical performance of AMed components is a necessity. In the present study, the mechanical behavior of AMed polymer parts under static and dynamic tests has been investigated. To this end, cantilever beams with three different mesostructure cells were designed and fabricated via ABS Carbon material based on the fused deposition modeling process. The specimens were subjected to a series of static bending tests and free vibration experiments. In addition, numerical models have been presented for both static bending and the dynamic tests. In the current study, digital image correlation technique has been employed to determine strain field and validate the numerical results. The experimental findings and numerical outcomes have been compared and the convergence has been investigated. Based on the applications of AM in fabrication of structural elements with complex geometries, the results of the current study are useful for new designs of AMed parts with customized mechanical strength and enhanced structural performance.

Cancer is a critical cause of global human death. Not only are complex approaches to cancer prognosis, accurate diagnosis, and efficient therapeutics concerned, but post-treatments like postsurgical or chemotherapeutical effects are also followed up. The four-dimensional (4D) printing technique has gained attention for its potential applications in cancer therapeutics. It is the next generation of the three-dimensional (3D) printing technique, which facilitates the advanced fabrication of dynamic constructs like programmable shapes, controllable locomotion, and on-demand functions. As is well-known, it is still in the initial stage of cancer applications and requires the insight study of 4D printing. Herein, we present the first effort to report on 4D printing technology in cancer therapeutics. This review will illustrate the mechanisms used to induce the dynamic constructs of 4D printing in cancer management. The recent potential applications of 4D printing in cancer therapeutics will be further detailed, and future perspectives and conclusions will finally be proposed.

This paper is focused on the design and development of the Porcospino Flex, a single-track robot inspired by nature and featuring a meta-material structure. In the earlier version of the Porcospino, the main body was composed of a chain of vertebrae and two end sections linked by flexible joints, but the excessive use of materials in 3D printing and the resulting weight of the robot posed challenges, ultimately leading to a decrease in its overall efficiency and performance. The Porcospino Flex is manufactured through the fused deposition modeling process using acrylonitrile butadiene styrene and thermoplastic polyurethane, featuring a singular meta-material structure vertebral column. The adoption of a lattice structure in the main body of the Porcospino Flex leads to a substantial increase in performance, reducing its weight from 4200 g to 3600 g. Furthermore, the decrease in weight leads to a reduction in material usage and waste, making a substantial contribution to the sustainability of the robot. The discussion focuses on the testing results of the Porcospino Flex prototype, highlighting the enhancements observed compared to its prior version.

Additive manufacturing (AM) processes are reliable techniques to build highly complex metallic parts. Direct energy deposition (DED) is one of the most common technologies to 3D print metal alloys. Despite a wide range of literature that has discussed the ability of DED in metal printing, weak binding, poor accuracy, and rough surface still exist in final products. Thus, limitations in 3D printing of metal powder and wire indicate post-processing techniques required to achieve high quality in both mechanical properties and surface quality. Therefore, hybrid manufacturing (HM), specifically additive/subtractive hybrid manufacturing (ASHM) of DED has been proposed to enhance product quality. ASHM is a capable process that combines two technologies with 3-axis or multi-axis machines. Different methods have been suggested to increase the accuracy of machines to find better quality and microstructure. In contrast, drawbacks in ASHM still exist such as limitations in existing reliable materials and poor accuracy in machine coordination to avoid collision in the multi-axes machine. It should be noted that there is no review work with focuses on both DED and hybridization of DED processes. Thus, in this review work, a unique study of DED in comparison to ASHM as well as novel techniques are discussed with the objective of showing the capabilities of each process and the benefits of using them for different applications. Finally, new gaps are discussed in ASHM to enhance the layer bonding and surface quality with the processes' effects on microstructures and performance.

This paper investigates integrating non-assembly three-dimensional (3D)-printed joints and soft robotic muscles in order to make a tendon-driven robotic finger. A finger-type structure actuated by electro-thermal soft actuator mechanism is introduced, including a bio-inspired 3D-printed compliant joint. As an affordable but high-performance component, twisted and coiled polymer (TCP) is used to drive the system as an actuator. The Euler–Lagrangian method and a transfer function based on an electro-thermo-mechanical model are used to analyze finger joints. The compliant joints are non-assembly 3D-printed spiral springs with high customization capabilities incorporated into the model. The simulation analysis is conducted to elucidate how the electro-thermal muscle and the spiral spring joint properties influence the finger motion. The results reveal further understanding of the 3D-printed spiral spring joints effects on the behavior of the soft robotic limbs. The suggested method can be adapted and employed in a broad variety of medicinal and industrial applications.

Vat photopolymerization-based three-dimensional (3D) printing techniques have been used as an efficient method for complex and special geometries in various applications. Composites are also a group of polymer materials that are obtained by adding a reinforcing component such as filler, fibres with different origins. Therefore, the development of 3D printable composites is paramount due to their high precision and speed of production. Glass beads (GBs) have been favorites as economical reinforcement agents for their chemical stability, water resistance in acidic environments, dimensional stability, and eco-friendly properties. In this study, 3D printable composites based on coated glass beads (CGBs) have been prepared. First, the beads are coated with ultraviolet (UV) curable resins to improve the interface with the polymer matrix. Then, CGBs are mixed with 3D printing resin and formulated for digital light processing (DLP) printing. The coating process is checked by scanning electron microscopy (SEM), and the mechanical properties of the 3D-printed composite structures have been evaluated by bending and compression tests. Also, the fracture behavior of cured resin has been checked with SEM. Mechanical property investigations have shown the success of the 3D printing of the CGBs into a photopolymer resin (PR) composite with behavior modification and compatibility of the interface with the matrix in practice.