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Stainless steel grade 304, is one of the most utilized grades of stainless steel and it is chosen for its corrosion resistance. The ideal option is 304, since its lower carbon content lowers intergranular corrosion, especially if corrosion resistance is a top goal for a project. This research work investigates the mechanical and microstructural characteristics of a novel double side fiber laser welded stainless steel 304 plates. Double side fiber laser welding technique is used to fabricate a butt joint with plates of thickness 5 mm. With a laser frequency of 25 Hz, speed of 6 mm ⋅ s−1, and a heat input of 1.4 kW in terms of power is applied to the joint, resulting in a maximum depth of penetration of 2.7 mm. The same parameter is applied on both sides of the plate. The dendritic structures are observed through micrographs of weld and pure metal captured using an optical microscope. Experiments such as tensile, bend, microhardness and impact test have been conducted to ensure the quality of weldment. The weldment consists of austenite and δ‐ferrite. X‐ray diffraction reveal presence of both austenite and ferrite in the weldment. Ductile mode of fracture occurred during failure of tensile samples. [ABSTRACT FROM AUTHOR]

There are concerns regarding the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from mother to child during this COVID pandemic. This descriptive study was done to check the possible transmission of the virus through breastfeeding in the Indian context. RT-qPCR for SARS-CoV-2 was done in breast milk samples from 30 COVID-positive mothers. Paired oropharyngeal swabs of the same neonates were also sent for RT-PCR at 48 h and on day 5 of life. All the breast milk samples were negative for SARS-CoV-2 except one. A repeat sample of breast milk from the same mother was also negative when rechecked the next day. All the paired neonatal oropharyngeal swabs were also negative for SARS-CoV-2. The authors could not find evidence for transmission of SARS-CoV-2 from mother to child through breastmilk in the population studied. [ABSTRACT FROM AUTHOR]