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In recent years, significant advancements in the development of large-scale 3D printers and construction materials have been made to meet the demand for industrial scale 3D printing construction. It is significant to construct the buildings and structural components by using 3D concrete printing. Additive manufacturing (AM) main benefits are freedom of design, construction waste reduction, mass customization, and ability to manufacture the complex structures. The major issues including the optimization of printing material which possess the suitable properties for 3D concrete printing. However, this technology towards the green building construction seems to improve the conventional methods by reducing the requirement of human resource, high investment cost, and formworks. The research community's interest in 3D printing for architecture and construction has grown significantly over the last few years. This paper review the latest trend of research and state of the art technologies in 3D printing in building and construction by analyzing the publications from 2002 to 2022. Based on aforementioned analysis of publications, printing methods, concrete printing systems and influence of constituent’s materials and chemical admixtures on concrete material properties are briefly discussed. Finally, this paper discussed the challenges and limitations of current systems, as well as potential future work to improve their capability and print quality.

Additive manufacturing technologies have emerged as the promising alternatives of conventional manufacturing techniques. Conventional manufacturing techniques involves cutting and removal of material by mechanical procedures to achieve final product. Whereas, discrete chunks of material in any form are combined point by point and layer by layer for the fabrication of final product in additive manufacturing processes. Numerous advantages and inefficiencies of these manufacturing techniques are reflected in factors such as the design, fabrication, material properties and working condition etc. Therefore, development of a production technology by combining the benefits of both conventional and additive techniques is significantly important. “Hybrid Manufacturing” jointly apply additive and conventional production methods to attain final products. Hence, this short overview covers the operation aspects of both additive and subtractive manufacturing of metallic materials.

Selective laser melting (SLM) has been considered as a well-researched technology used to produce near net shape metallic components with superior mechanical and physiochemical characteristics. Recently SLM has recently been used for the production of components made by high-performance alloys such as Titanium and Nickel. However, the microstructural and physical anisotropy along with the defects have negative impact on the performance and behavior of SLM-produced alloys. Therefore, to improve the material characteristics, extra attention must be paid to the source(s), identification, and removal of these deviations. Thermal heat treatments are often considered as an effective approach to deal with aforementioned issues. stress-relieving, quenching/hardening, annealing/recrystallization, and thermo-mechanical heat treatments are among prominent procedures adopted for the post processing of SLM fabricated metallic components and hence considered in this article. Since these procedures have substantial impact on the microstructure and mechanical behavior therefore an assessment of their influence and resulting changes is significantly important. Therefore, this short review provides the said knowledge on thermal treatments used to improve the SLM fabricated titanium and nickel-based alloys. This review can significantly help in designing and selecting appropriate post processing thermal treatments keeping in mind the expected outcome.

Objective: To evaluate the decision to delivery interval (DDI) of category-1 and category-2 emergency caesarean section (ECS) and its effect on neonatal and maternal outcomes. Study Design: Cross-sectional study. Place and Duration of Study: The study was carried out at Combine Military Hospital (CMH), Kharian, Pakistan from February 2022 to February 2023. Methods: Data from 332 patients who underwent emergency caesarean section (ECS) at a tertiary care hospital were collected on a structured proforma and analyzed. Feto-maternal outcomes were dependent, and time to decision to delivery interval were independent variables. Results: Out of 332 ECS, 126 were Category 1, and 206 were category 2. The percentages of emergency caesarean section (ECS) done within the recommended DDI were 39.5% for category 1 and 20.5% for category 2. The median (IQR) of DDI was 45 (37–54) min and 90 (75–98) min for category 1 and category 2. Eclampsia, fetal distress and failed progress of labor were the most typical indications. In both types, there was no statistically significant poor neonatal outcome related to APGAR at 1 min and 5 min. Delays were associated with more cases of post-operative fever 74 (36) and 22(13.3) in category 2 than in category 1 ECS. Conclusion: Our study found delays in the decision-to-delivery interval (DDI) for both category 1 and category 2 emergency Caesarean sections. However, no statistically significant association was found between neonatal and maternal outcomes. How to cite this: Parveen S, Waqar S. Decision to Delivery Interval of Emergency Caesarean Sections: Evaluating Adherence to Timeframe and its Impact on Feto-Maternal Outcomes. Life and Science. 2023; 4(4): 445-451. doi: http://doi.org/10.37185/LnS.1.1.424

Powder bed fusion based additive manufacturing techniques involve melting or sintering of powder particles via laser beams to join them in order to attain desired shapes. This study aims to provide basis for material constitutive parameters of widely used aluminum alloy AlSi10Mg alloy. Initially, tensile samples of AlSi10Mg alloy samples were manufactured by using SLM technology. Afterwards, through quasi-static and high temperature tensile tests, an attempt has been made to determine the Johnson–Cook material model of AlSi10Mg. in order to conduct quasi-static tensile tests, strain rates of 10−3 s−1, 10−2 s−1 and 5 × 10−2 s−1 were considered and tests were conducted at ambient temperature. Whereas, for high temperature tensile tests 24, 150, 300 °C temperature values were considered at the reference strain rate value of 10−3 s−1. The numerically simulated tensile results achieved by using the established Johnson–Cook model were then compared with experimental results. It was observed that the maximum error between the test and simulation results was around of 7.5%. The error percentage is well within the acceptable, thus proving the accuracy of the established material model.