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The phase transition and grain refinement features of a Ti-6Al-4V alloy are investigated in this study using in-situ high- temperature Electron Backscatter Diffraction (EBSD). The objective of the experiment was to detect the phase transition from Body-Centered Cubic (BCC) to Face-Centered Cubic (FCC) systems at temperatures ranging from 770 to 900 degrees Celsius. Grain refinement techniques such as recrystallization twin generation, Kernel Average Misorientation (KAM), and low-angle grain boundary creation were the focus of this study. According to our research, phase transformation maps taken at 770°C, 810°C, 840°C, and 900°C reveal that a discontinuous recrystallization process was responsible for the transformation and recrystallization. The results of this investigation provide support to the theory that high-temperature treatments may enhance the microstructure of additively made Ti-6Al-4V alloys. At temperatures of 900 °C, the grain structure was evenly polished, and an almost complete phase shift to a face-centered cubic (FCC) shape was observed.

This research examines the amalgamation of Circular Economy concepts with Lean Six Sigma approaches to enhance manufacturing operations, emphasizing waste minimization, resource efficiency, and economic performance. The study assesses the influence of Lean Six Sigma on production efficiency and environmental sustainability via empirical analysis and process optimization methodologies. Conventional manufacturing procedures, including machining, milling, and grinding, were assessed for resource utilization and waste production, revealing that Lean Six Sigma methodologies markedly decreased material waste, especially in milling operations, where waste was curtailed by 20%. Advanced precision techniques, including CNC and laser cutting, were evaluated for their efficiency, with CNC cutting realizing a 15% decrease in energy usage and a 30% enhancement in material utilization. Laser cutting exhibited improved accuracy, resulting in a 35% decrease in rework and scrap. The economic study indicated that the application of Lean Six Sigma in CNC operations resulted in a 25% reduction in operating expenses over time, albeit greater initial expenditures. These results provide significant insights into the enhancement of industrial efficiency and the promotion of sustainable production practices via the integration of Circular Economy concepts with Lean Six Sigma methodologies. Keywords: Circular Economy, Precision Manufacturing, Comparative Analysis, Tool Life, Economic Implications.

To achieve high agricultural yields, it is essential to predict the soil temperature and moisture regime, considering the heating technology employed. The research object is soil heated by a ceiling-mounted infrared emitter. The research subject encompasses one-dimensional unsteady fields of soil moisture content and temperature. The research goal is to forecast the soil temperature and moisture regime under radiant heating conditions. The research methods involve the analytical solution of heat and mass transfer differential equations using the method of finite integral Fourier transforms. Research results indicate that the top layer of milled peat, with an initial moisture content of 3.7 kg/kg, will reach a final moisture content of 1.0 kg/kg in approximately 6 hours during infrared drying. As a result of radiant heating, the soil temperature will rise from an initial 5 ℃ to a final 22.6 ℃ in approximately 3 hours. The analytical solution of the mass transfer differential equation can be utilized for theoretical studies of drying capillary-porous materials, such as determining the drying period or the thickness of the material layer that will dry to a specified final moisture content. The analytical solution of the heat transfer differential equation, accounting for both thermal conductivity and the Dufour effect, can be employed to manage the operation of the infrared radiation source, such as determining its operational and shutdown periods when the soil surface temperature reaches its maximum (critical) value. The mathematical solutions discussed in the article do not consider thermodiffusion processes in the soil layer (Soret effect), which presents a promising direction for further scientific research.

Flaviviruses such as dengue virus (DENV), Zika virus (ZIKV), and yellow fever virus (YFV) are spread by mosquitoes and cause human disease and mortality in tropical areas. In contrast, Powassan virus (POWV), which causes severe neurologic illness, is a flavivirus transmitted by ticks in temperate regions of the Northern hemisphere. We find serologic neutralizing activity against POWV in individuals living in Mexico and Brazil. Monoclonal antibodies P002 and P003, which were derived from a resident of Mexico (where POWV is not reported), neutralize POWV lineage I by recognizing an epitope on the virus envelope domain III (EDIII) that is shared with a broad range of tick- and mosquito-borne flaviviruses. Our findings raise the possibility that POWV, or a flavivirus closely related to it, infects humans in the tropics., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

This article proposes a new framework using physics-informed neural networks (PINNs) to simulate complex structural systems that consist of single and double beams based on Euler-Bernoulli and Timoshenko theories, where the double beams are connected with a Winkler foundation. In particular, forward and inverse problems for the Euler-Bernoulli and Timoshenko partial differential equations (PDEs) are solved using nondimensional equations with the physics-informed loss function. Higher order complex beam PDEs are efficiently solved for forward problems to compute the transverse displacements and cross-sectional rotations with less than 1e-3 % error. Furthermore, inverse problems are robustly solved to determine the unknown dimensionless model parameters and applied force in the entire space-time domain, even in the case of noisy data. The results suggest that PINNs are a promising strategy for solving problems in engineering structures and machines involving beam systems.

Introduction: Lyme disease (LD) affects ∼476,000 people each year in the United States. Symptoms are variable and include rash and flu-like symptoms. Reasons for the wide variation in disease outcomes are unknown. Powassan virus (POWV) is a tick-borne flavivirus that causes disease ranging from asymptomatic infection to encephalitis, neurologic damage, and death. POWV and LD geographic case distributions overlap, with Ixodes species ticks as the common vectors. Clinical ramifications of coinfection or sequential infection are unknown. Objectives: This study's primary objective was to determine the prevalence of POWV-reactive antibodies in sera samples collected from previously studied cohorts of individuals with self-reported LD history residing in the Northeastern United States. As a secondary objective, we studied clinical differences between people with self-reported LD history and low versus high POWV antibody levels. Methods: We used an enzyme-linked immunosorbent assay (ELISA) to quantify IgG directed at the POWV envelope (E) protein domain III in 538 samples from individuals with self-reported LD history and 16 community controls. The samples were also tested with an ELISA assay to quantify IgG directed at the POWV NS1 protein. Results: The percentage of individuals with LD history and possible evidence of POWV exposure varied depending on the assay utilized. We found no significant difference in clinical symptoms between those with low or high POWV IgG levels in the in-house assay. Congruence of the EDIII and NS1 assays was low with only 12% of those positive in the in-house EDIII ELISA testing positive in the POWV NS1 ELISA. Conclusions: The results highlight the difficulty in flavivirus diagnostic testing, particularly in the retrospective detection of flavivirus exposure. The findings suggest that a prospective study with symptomatic patients using approved clinical testing is necessary to address the incidence and clinical implications of LD and POWV co-infection or sequential infection.