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Lipomas are common benign neoplastic mesenchymal tumours arising from adipose tissue anywhere in the body. Giant intra-thoracic lipoma extending across the anterior mediastinum into bilateral pleural spaces causing compression of the underlying lung resulting in respiratory embarrassment is rarely seen and reported. Giant lipomas of thorax require surgical excision as they continue to grow and cause compressive symptoms.

Indentation Size Effect (ISE) in steels having a wide spectrum of carbon (C) concentrations (wt-%) 0.002 (interstitial-free), 0.07 (microalloyed), 0.19 (low carbon), 0.32 (medium carbon), and 0.7 (high carbon), and microstructures were investigated using Vickers micro-hardness tester. A decrease in micro-hardness with increasing load, i.e. ISE, is observed in all the samples except microalloyed steel. The empirical relations, such as the Nix and Gao model, Minimum Resistance model, and Proportional Specimen Resistance (PSR) model, were used to determine the load-independent or true hardness values. Nix and Gao model was adopted to determine the plastically deformed zone (PDZ) size under the indenter and subsequently correlated with ISE in the materials. It is observed that ISE is absent when the PDZ size becomes comparable to or larger than the grain size of the material.

Indentation Size Effect (ISE) in steels having a wide spectrum of carbon (C) concentrations (wt-%) 0.002 (interstitial-free), 0.07 (microalloyed), 0.19 (low carbon), 0.32 (medium carbon), and 0.7 (high carbon), and microstructures were investigated using Vickers micro-hardness tester. A decrease in micro-hardness with increasing load, i.e. ISE, is observed in all the samples except microalloyed steel. The empirical relations, such as the Nix and Gao model, Minimum Resistance model, and Proportional Specimen Resistance (PSR) model, were used to determine the load-independent or true hardness values. Nix and Gao model was adopted to determine the plastically deformed zone (PDZ) size under the indenter and subsequently correlated with ISE in the materials. It is observed that ISE is absent when the PDZ size becomes comparable to or larger than the grain size of the material.

Introduction: The January 2023 COVID-19 omicron wave in China garnered wide publicity partly because it evaded most vaccines at that time and resulted in “breakthrough infections” in previously vaccinated individuals. This study focused on the COVID-19 vaccination status and the response of foreigners of African descent who were in China during the January 2023 Omicron-driven COVID-19 wave. Materials and methods: A cross-sectional online survey of Africans in China was conducted in January 2023. Self-report electronic questionnaires were sent to eligible participants across the country, with no restriction on age, gender, or country of origin. Two hundred sixty-six participants were eventually enrolled. Collected data was cleaned and analyzed using SPSS. Descriptive analysis was used to summarize the data in terms of numbers and percentages, while the Chi-square test was used to determine relationships among variables. Results: A total of 266 participants were enrolled, 68.8% males and 31.2% females. The majority (97%) were 45 years and below and mostly students (75.2%). 87.2% were vaccinated, with 53.1% having taken at least 2 shots. Sinovac (53.9%) was the most used vaccine brand. 21.4% reported infection with COVID-19 during the January 2023 omicron wave, with 14.0% reporting “breakthrough” infections. No significant difference was seen in the risk of getting infected with COVID-19 between unvaccinated and vaccinated participants; OR 1.2 (95% CI 0.396–3.634, p= 0.747). 35.1% reported mild asymptomatic infections, while 64.9% reported symptoms. The majority of the cases (89.5%) were managed from home. Conclusion: In summary, most Africans in China were vaccinated during the January 2023 COVID-19 omicron wave, although “breakthrough” infections were reported. The infection rate among Africans in China was relatively higher than for African Americans and those living in Africa, but the majority were managed from home. Future studies are needed to capture vital COVID-19 information on Africans in China for more trailered responses to future outbreaks.

Current study deals with the microstructural characterization of five different plates of steel with carbon concentration ranging from ultra-low to moderately high. Phase analysis was carried out using XRD technique. The XRD results were analyzed through Rietveld refinement and Williamson Hall plots. Rietveld refinement was carried out to understand the effect of carbon concentration on the lattice parameters of the above steel samples in as-received condition and also after deformation under uni-axial tensile loading. Lattice parameters obtained from refinement showed the strong dependence on carbon concentration of the given steels. But the failed specimens showed somewhat complex results as Spheroidized high carbon steel, Low carbon steel and IF steel showed an increase in lattice parameter whereas Medium carbon steel and Microalloyed steel showed a contraction in lattice parameter. Williamson Hall plot gave the crystallite size, microstrain and dislocation density in the steels. For IF and Microalloyed steels the dislocation density in the material is found to be higher after deformation whereas dislocation density decreased in Spheroidized high carbon steel, Medium carbon steel and Low carbon steel.

Recycling has been the fascinating topic among the researchers for all times. The present study shows the recycling of steel plant's solid wastes as blast furnace flue dust and sludge towards agglomeration and their use in the production of sinter. These wastes consist of metal oxides and coke fines as a valuable material with some alkali oxides. Using these wastes as it is in the form of fines exacerbate the further processing. Pellets of these wastes are prepared with three types of binders as molasses, dextrin and bentonite. The result reveals that properties as compressive strength, shatter strength, are better in the case of bentonite binder having the productivity of the disc pelletizer machine as 75. After that, these macro pellets used for sintering with iron ore and other ingredients in pot type, down draft laboratory grade sintering machine, which shows very high productivity and good mechanical properties of the sinter as well. The microstructural analysis reveals the presence of re-oxidized hematite and a little bit of a magnetite phase with some slag phases, which confirmed later by XRD analysis. Results also show the decrease in coke rate, i.e. coke consumption to produce sinter and at the same time, this process is highly eco-friendly.

This paper discusses the behavior of solid wastes such as blast furnace flue dust and sludge in steel plants. These wastes consist of metal oxides and coke fines as valuable materials with some alkali oxides. Processing of the wastes as it is obtained from a plant is challenging. In this study, pellets of these wastes were prepared with three types of binders such as molasses, dextrin and bentonite. These pellets were used for the preparation of iron ore sinter in a pot-type laboratory-grade sintering machine. The results reveal that compressive strength and shatter strength are better in the case of bentonite binder. This binder provides high compressive strength as well as minimum shatter index value. Thereafter, utilization of these carbon-containing pellets in sintering operation improves the productivity of sintering machine as well as decreases coke consumption in the process.