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Ferritic stainless steels (FSS) develop poor surface finish during processing and this is attributed to the large columnar grains formed during solidification. Addition of alloying elements such as Al, Ti and Nb used in dual stabilized FSS improve the solidification structures. In this work, two 441 dual stabilized FSS, with 0.023 and 0.068 %Al respectively were investigated in the as-cast condition. The columnar to equiaxed zone ratio was determined by the linear interception method. The results showed that the higher the Ti/Al ratio, the higher the equiaxed ratio. The inclusions reported from SEM showed that there were more spinel inclusions of Ti-Al-O as well as more TiN precipitates in the steel with 0.023 wt% Al.

Abstract Autonomous self-healing anticorrosion protective coatings from intrinsic polymers is a great challenge. In this work, in-situ self-crosslinking strategy was demonstrated for constructing self-healing anticorrosion polymers. The as-synthesized polymers had tunable catechol content and mechanical properties. The specimens could be repaired in an Fe3+ solution owing to the formation of dynamic catechol-Fe3+ coordination crosslinking sites. Moreover, when scratched, the prepared polymers exhibited a self-healing anticorrosion performance, as evidenced by salt immersion and electrochemical impedance spectroscopy. An in-situ self-crosslinking mechanism was proposed, which was derived from the dynamic coordination of catechol groups in the polymer chains and Fe3+ produced from the metal substrate. This intrinsic self-healing anticorrosion polymer are highly potential for anticorrosion applications in harsh environments.

The article presents questions and answers on topics including use of developing world as an easy target for the populism and ways to control the negative impact of social media on democracy.

This study presents the investigation of the influence of heat treatment on microstructure, hardness and tensile properties of high-speed selective laser melted Ti6Al4V components. Heat treatment was performed to obtain an improved microstructure with enhanced hardness and tensile properties. It was found that the acicular martensitic α′ structure on the as-built sample lead to high hardness, yield strength and ultimate tensile strengths of 389±10 HV0.3, 949 ± 10 MPa and 1045 ± 3 MPa, respectively,with a low ductility of 5%. Heat treatment transformed the martensitic α′ structure into lamella α + β phases, with heat treatment at 1000 °C resultingin the most improved hardness and ductility from 389 ± 10 HV0.3 and 5% to 325 ± 20 HV0.3 and 13%, and a decrease in yield and ultimate tensile strength from 949 ± 10 MPa and 1045 ± 13MPa to 835 ± 11 MPa and 911 ± 5 MPa, respectively.

The following article looks at using scanning electron microscopy- electron back scatter diffraction techniques to study recrystallisation structures produced through hot rolling of 436 ferritic stainless steel. Characterisation of recrystallisation textures was undertaken through analysis of misorientation angle distribution diagrams, orientation distribution function maps, inverse pole figures and Taylor factor maps. These techniques were applied in a case study where typical industrial hot rolling conditions were simulated through uniaxial compression tests in a Bähr Dilatometer 850D, whereby the effect of strain rate and interpass time on recrystallisation structures was investigated.

High impact polystyrene (HIPS) material is widely used for low-strength structural applications. To ensure proper function, dimensional accuracy and porosity are at the forefront of industrial relevance. The dimensional accuracy cylindricity error (CE) and porosity of printed parts are influenced mainly by the control variables (layer thickness, shell thickness, infill density, print speed of the fused deposition modeling (FDM) process). In this study, a central composite design (CCD) matrix was used to perform experiments and analyze the complete insight information of the process (control variables influence on CE and porosity of FDM parts). Shell thickness for CE and infill density for porosity were identified as the most significant factors. Layer thickness interaction with shell thickness, infill density (except for CE), and print speed were found to be significant for both outputs. The interaction factors, i.e., shell thickness and infill density, were insignificant (negligible effect) for both outputs. The models developed produced a better fit for regression with an R2 equal to 94.56% for CE, and 99.10% for porosity, respectively. Four algorithms (bald eagle search optimization (BES), particle swarm optimization (PSO), RAO-3, and JAYA) were applied to determine optimal FDM conditions while examining six case studies (sets of weights assigned for porosity and CE) focused on minimizing both CE and porosity. BES and RAO-3 algorithms determined optimal conditions (layer thickness: 0.22 mm; shell thickness: 2 mm; infill density: 100%; print speed: 30 mm/s) at a reduced computation time equal to 0.007 s, differing from JAYA and PSO, which resulted in an experimental CE of 0.1215 mm and 2.5% of porosity in printed parts. Consequently, BES and RAO-3 algorithms are efficient tools for the optimization of FDM parts.

Abstract Background Microorganisms have provided a wealth of metabolites with interesting activities such as antimicrobial, antiviral and anticancer. In this study, a total of 119 aquatic microbial isolates from 30 samples (taken from water bodies in Ghana) were screened by the agar-well diffusion method for ability to produce antibacterial-metabolites. Results Antibacterial activity was exhibited by 27 of the isolates (14 bacteria, 9 actinomycetes and 4 fungi) against at least one of the indicator microorganisms: Enterococcus faecalis (ATCC 29212), Bacillus thuringiensis (ATCC 13838), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Proteus vulgaris (NCTC 4635) and Bacillus Subtilis (NCTC 10073). A sea isolate MAI2 (identified as a strain of Pseudomonas aeruginosa) exhibited the highest antibacterial activity (lowest zone of inhibition = 22 mm). The metabolites of MAI2 extracted with chloroform were stable to heat and gave minimum inhibitory concentrations ranging between 250 and 2000 μg/ml. Bioautography of the extract revealed seven active components. Conclusion This study has therefore uncovered the potential of water bodies in the West African sub-region as reservoirs of potent bioactive metabolite producing microorganisms.

We studied 1,238 patients receiving 1,880 coronary stents. In-hospital outcomes were divided by age into <65 years (n = 747, group 1), 65 to 75 years (n = 326, group 2), and >75 years (n = 165, group 3). Procedural success was 97.2%, 95.1%, and 98.8% in groups 1, 2, and 3, respectively (p = NS). There was 1 death (group 1). Myocardial infarction occurred in 1.2%, 2.8%, and 1.8%, bypass surgery occurred in 0.9%, 1.8%, and 1.2%, and repeat balloon angioplasty in 0.3%, 0.6%, and 0% of patients in groups 1, 2, and 3, respectively (p = NS for all comparisons). Vascular complications occurred in 2.8%, 4.9%, and 6.1% in groups 1, 2, and 3, respectively (p <0.05). Six-month follow-up of patients was divided by age: <65 years (n = 564, group 1); 65 to 75 years (n = 221, group 2); and >75 years (n = 122, group 3). Event-free survival was 94.5%, 90.5%, and 89.3% for groups 1, 2, and 3, respectively (p = NS). Death occurred in 0.4%, 0.5%, and 1.6%; myocardial infarction occurred in 1.2%, 2.3%, and 1.6%, and target vessel revascularization in 4.3%, 8.6%, and 7.4% for groups 1, 2, and 3, respectively (p = NS for all comparisons). Thus, coronary stenting produced favorable in-hospital and 6-month outcomes in all 3 age groups. Age itself should not preclude patients from undergoing coronary stenting. [ABSTRACT FROM AUTHOR]

Background and Aims: The Chat Generative Pre-Trained Transformer (ChatGPT) represents a significant advancement in artificial intelligence (AI) chatbot technology. While ChatGPT offers promising capabilities, concerns remain about its reliability and accuracy. This study aims to evaluate ChatGPT's responses to patients' frequently asked questions about Endoscopic Sleeve Gastroplasty (ESG)., Methods: Expert Gastroenterologists and Bariatric Surgeons, with experience in ESG, were invited to evaluate ChatGPT-generated answers to eight ESG-related questions, and answers sourced from hospital websites. The evaluation criteria included ease of understanding, scientific accuracy, and overall answer satisfaction. They were also tasked with discerning whether each response was AI generated or not., Results: Twelve medical professionals with expertise in ESG participated, 83.3% of whom had experience performing the procedure independently. The entire cohort possessed substantial knowledge about ESG. ChatGPT's utility among participants, rated on a scale of one to five, averaged 2.75. The raters demonstrated a 54% accuracy rate in distinguishing AI-generated responses, with a sensitivity of 39% and specificity of 60%, resulting in an average of 17.6 correct identifications out of a possible 31. Overall, there were no significant differences between AI-generated and non-AI responses in terms of scientific accuracy, understandability, and satisfaction, with one notable exception. For the question defining ESG, the AI-generated definition scored higher in scientific accuracy (4.33 vs. 3.61, p = 0.007) and satisfaction (4.33 vs. 3.58, p = 0.009) compared to the non-AI versions., Conclusions: This study underscores ChatGPT's efficacy in providing medical information on ESG, demonstrating its comparability to traditional sources in scientific accuracy., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Despite the increasing number of bariatric procedures over the recent years, the physiological changes in secondary esophageal motility and distensibility parameters after surgery remain unknown., Methods: This is a retrospective, single-center cohort study comparing esophageal planimetry and gastroesophageal junction (GEJ) distensibility in post-bariatric surgery patients (Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and conversion/revisional patients (DH)) and native-anatomy patients with obesity (NAC). Distensibility refers to the area achieved with a certain amount of pressure, and secondary peristalsis represents the esophageal response to an intended obstruction. Patients with pre-surgical dysmotility symptoms were excluded from the study., Results: From November 2018 to January 2023, 167 patients were evaluated and eligible for this study (RYGB = 87, SG = 33, NAC = 22, DH = 25). In NAC cohort, 17/22 (77%) patients presented normal motility patterns compared to 35/87 (40%) RYGB, 12/33 (36%) SG, and 5/25 (20%) DH (p < 0.05 for all comparisons). The most common abnormal motility pattern for all three bariatric cohorts was absent contractions. DH patients generally had the highest mean maximum distensibility index averages, followed by SG, RYGB, and NAC., Conclusion: Bariatric surgery affects esophageal and GEJ physiology, and it is associated with higher rates of secondary dysmotility. DH patients have even higher rates of dysmotility. Further studies assessing clinical data and their correlation with manometric and pH-metric findings are needed., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background and study aims Traditional transoral outlet reduction (TORe) is a minimally invasive endoscopic approach focused on reducing the aperture of the gastrojejunal (GJ) anastomosis, while the tubular transoral outlet reduction (tTORe) consists of tabularization of the distal pouch utilizing an O-shape gastroplasty suturing pattern. The primary aim of this study was to compare short-term weight loss between TORe and tTORe. Patients and methods Retrospective analysis of a prospectively maintained database was conducted at a tertiary care bariatric center of excellence. The study included patients with history of Roux-en-Y gastric bypass (RYGB) who had an endoscopic revision by TORe or tTORe and had follow-up data in their electronic medical record. The primary outcome was percent total body weight loss (%TBWL). Results A total of 128 patients were included (tTORe=85, TORe=43). At 3 and 6 months, the tTORe and TORe cohorts presented similar %TBWL (3 months: 8.5±4.9 vs. 7.3±6.0, P = 0.27 and 6 months: 8.1±7.4 vs. 6.8±5.6, P = 0.44). At 9 months, there was a trend toward greater weight loss in the tTORe cohort (9.7±8.6% vs. 5.1±6.8%, P = 0.053). At 12 months, the %TBWL was significantly higher in the tubularization group compared to the standard group (8.2±10.8 vs. 2.3±7.3%, P = 0.01). Procedure time was significantly different between both groups (60.5 vs. 53.4 minutes, P = 0.03). The adverse events rate was similar between groups (8.2% vs. 7.0% for tTORe and TORe, respectively, P = 0.61). Conclusions The tTORe enhances efficacy and durability of the standard procedure without adding significant procedure-related risks., Competing Interests: Conflict of Interest BKA reports consultant roles with Endogenex, Endo-TAGSS, Metamodix, and BFKW; consultant and grant/research support from USGI, Cairn Diagnostics, Aspire Bariatrics, Boston Scientific; Speaker roles with Olympus, Johnson and Johnson; speaker and grant/research support from Medtronic, Endogastric solutions; and research support from Apollo Endosurgery, and Spatz Medical. ACS reports institutional research grants from Boston Scientific, Enterasense, Endogenex; consulting fees from Olympus; consulting fees and research grants from Endo-TAGSS, and Apollo Endosurgery; Participation in Data Safety Monitoring Board with GI Dynamics, and ERBE. VOB: Honoraria payment for lectures and testimonies from Erbe Elektromedizin GMHB. All other authors have no COI., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)