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Nickel‐free high‐nitrogen‐alloyed stainless steels like the P2000 (X13CrMnMoN18‐14‐3) were developed to enhance the strength and corrosion resistance of austenitic stainless steels like 304 and 316 while keeping the typical high ductility. The mechanical and corrosive properties of P2000 were investigated and compared with 304 and 316 to highlight the application opportunities of this new alloy. The microstructure of the solution‐annealed condition was characterised by electron backscatter diffraction and the mechanical properties were studied by uniaxial tensile tests, Charpy impact tests and hardness measurements. The passivation behaviour was analysed using the electrochemical potentiodynamic reactivation, whereas the pitting corrosion resistance was compared by pitting potentials and pitting temperatures. However, secondary thermal influences or suboptimal heat treatment can impair the corrosion resistance due to the precipitation of secondary phases and the resulting sensitisation. Thermodynamic calculations and artificial ageing treatment in the range of 500–900°C for up to 100 h were used to determine critical time–temperature parameters for sensitisation. The microstructure of the various aged states was evaluated by scanning electron microscopy and compared with the degrading corrosion resistance characterised by the KorroPad method. [ABSTRACT FROM AUTHOR]

In the present study a new approach on strengthening of innovative high-temperature Me-Si-B (Me = Mo, V) materials by Y 2 O 3 particles is presented. This approach combines the oxide dispersed strengthening (ODS) mechanism and additive processing of innovative intermetallic materials. To this end, gas atomized powder material, suitable for additive manufacturing, was doped with Y 2 O 3 particles. Bulk materials were manufactured via direct energy deposition (DED), which is an efficient method to generate crack-free Me-Si-B alloys. The DED process further allows the homogeneous distribution of Y 2 O 3 particles in the intermetallic matrix. Hardness measurements as well as uniaxial compression tests depict the potential of novel Y 2 O 3 reinforced Me-Si-B alloys. • Innovative Y 2 O 3 reinforced high-temperature Me-Si-B alloys • Gas atomization • Additive manufacturing [ABSTRACT FROM AUTHOR]

The world heritage object Nebra Sky Disc is one of the best investigated archaeological objects. The origin of the raw materials it is made of is well known. However, its manufacturing process was not completely clear. Investigations were made in order to clarify the steps of manufacturing from the initial casting to the finished disc using the latest metallographic techniques. Therefore, a small piece from the outer part of the disc was investigated and compared with a replica. Both were prepared regarding the metallographic procedure. Microstructural analysis was made by optical microscopy on a colour etched surface, EDS and electron backscatter diffraction. For the investigation of mechanical properties microhardness measurements were made. It could be found that the Nebra Sky Disc was manufactured from a flat cast followed by hot forging process. During the forging process the disc was heated and forged for approximately 10 times., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Background: Internationally, potential effects of national SARS-CoV-2-related lockdowns on stillbirth rates have been reported, but data for Germany, including risk factors for fetal pregnancy outcome, are lacking. The aim of this study is to compare the stillbirth rates during the two first lockdown periods in 2020 with previous years from 2010 to 2019 in a large Bavarian cohort., Methods: This study is a secondary analysis of the Bavarian perinatal data from 2010 to 2020, including 349,245 births. Univariate and multivariable regression analyses were performed to investigate the effect of two Bavarian lockdowns on the stillbirth rate in 2020 compared to the corresponding periods from 2010 to 2019., Results: During the first lockdown, the stillbirth rate was significantly higher compared to the reference period (4.04 vs. 3.03 stillbirths per 1000 births; P = 0.03). After adjustment for seasonal and long-term trends, this effect can no longer be observed (P = 0.2). During the second lockdown, the stillbirth rate did not differ in univariate (3.46 vs. 2.93 stillbirths per 1000 births; P = 0.22) as well as in multivariable analyses (P = 0.68), compared to the years 2010 to 2019., Conclusion: After adjustment for known long-term effects, in this study we did not find evidence that the two Bavarian lockdowns had an effect on the rate of stillbirths., (© 2022. The Author(s).)

Aim The AGG (Working Group for Obstetrics and Prenatal Diagnostics, Section Maternal Diseases) has issued these recommendations to improve the detection and management of Toxoplasma gondii infection in pregnancy. Methods Members of the Task Force developed the recommendations and statements presented here using recently published literature. The recommendations were adopted after a consensus process by members of the working group. Recommendations This article focuses on the epidemiology and pathophysiology of Toxoplasma gondii infection in pregnancy and includes recommendations for maternal and fetal diagnosis, transmission prophylaxis, therapy, prevention, screening, and peripartum management., Competing Interests: Conflict of Interest/Interessenkonflikt The authors declare that they have no conflict of interest., (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 commecial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).)

Objective: Identify and review the body of tobacco research literature that self-identified as using machine learning (ML) in the analysis., Data Sources: MEDLINE, EMABSE, PubMed, CINAHL Plus, APA PsycINFO and IEEE Xplore databases were searched up to September 2020. Studies were restricted to peer-reviewed, English-language journal articles, dissertations and conference papers comprising an empirical analysis where ML was identified to be the method used to examine human experience of tobacco. Studies of genomics and diagnostic imaging were excluded., Study Selection: Two reviewers independently screened the titles and abstracts. The reference list of articles was also searched. In an iterative process, eligible studies were classified into domains based on their objectives and types of data used in the analysis., Data Extraction: Using data charting forms, two reviewers independently extracted data from all studies. A narrative synthesis method was used to describe findings from each domain such as study design, objective, ML classes/algorithms, knowledge users and the presence of a data sharing statement. Trends of publication were visually depicted., Data Synthesis: 74 studies were grouped into four domains: ML-powered technology to assist smoking cessation (n=22); content analysis of tobacco on social media (n=32); smoker status classification from narrative clinical texts (n=6) and tobacco-related outcome prediction using administrative, survey or clinical trial data (n=14). Implications of these studies and future directions for ML researchers in tobacco control were discussed., Conclusions: ML represents a powerful tool that could advance the research and policy decision-making of tobacco control. Further opportunities should be explored., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction International studies on preterm birth rates during COVID-19 lockdowns report different results. This study examines preterm birth rates during lockdown periods and the impact of the mobility changes of the population in Bavaria, Germany. Material and Methods This is a secondary analysis of centrally collected data on preterm births in Bavaria from 2010 to 2020. Preterm births (< 37 weeks) in singleton and twin pregnancies during two lockdowns were compared with corresponding periods in 2010 - 2019. Fisher's exact test was used to compare raw prevalence between groups. Potential effects of two fixed lockdown periods and of variable changes in population mobility on preterm birth rates in 2020 were examined using additive logistic regression models, adjusting for long-term and seasonal trends. Results Unadjusted preterm birth rates in 2020 were significantly lower for singleton pregnancies during the two lockdown periods (Lockdown 1: 5.71% vs. 6.41%; OR 0.88; p < 0.001; Lockdown 2: 5.71% vs. 6.60%; OR = 0.86; p < 0.001). However, these effects could not be confirmed after adjusting for long-term trends (Lockdown 1: adj. OR = 0.99; p = 0.73; Lockdown 2: adj. OR = 0.96; p = 0.24). For twin pregnancies, differences during lockdown were less marked (Lockdown 1: 52.99% vs. 56.26%; OR = 0.88; p = 0.15; Lockdown 2: 58.06% vs. 58.91%; OR = 0.97; p = 0.70). Reduced population mobility had no significant impact on preterm birth rates in singleton pregnancies (p = 0.14) but did have an impact on twin pregnancies (p = 0.02). Conclusions Reduced preterm birth rates during both lockdown periods in 2020 were observed for singleton and twin pregnancies. However, these effects are reduced when adjusting for long-term and seasonal trends. Reduced population mobility was associated with lower preterm birth rates in twin pregnancies., Competing Interests: Conflict of Interest The authors declare that they have no conflict of interest., (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 commecial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).)

Fretting corrosion is associated with increased risk of premature implant failure. In this complex in vivo corrosion system, the contribution of static crevice corrosion of the joined metal alloys is still unknown. The aim of this study was to develop a methodology for testing crevice corrosion behavior that simulates the physiological conditions of modular taper junctions and to identify critical factors on corrosion susceptibility. Samples of medical grade CoCr28Mo6 cast and wrought alloy, TiAl6V4 wrought alloy and REX 734 stainless steel were prepared metallographically and the microstructure was investigated using scanning electron microscopy (SEM). Crevice formers that mimic typical geometries of taper junctions were developed. Crevice corrosion immersion tests were performed in different physiological fluids (bovine serum or phosphate buffered saline with additives of 30 mM H 2 O 2 at pH = 1) for 4 weeks at 37°C. SEM with energy dispersive X-ray spectroscopy as well as focused ion beam were used to characterize the surface morphology, investigate present damages and identify the chemical composition of residues. Macroscopic inspection showed increased crevice corrosion susceptibility of TiAl6V4 and REX 734 under severe simulated inflammatory conditions. CoCr28Mo6 cast alloy exhibited degraded areas next to Cr- and Mo-rich precipitations that were located within the opposed crevices. The results indicate that aggressive electrolyte composition and crevice heights of 50-500 μm are critical influencing factors on crevice corrosion of biomedical alloys. Furthermore, manufacturing-related microstructure of common implant alloys determines the deterioration of corrosion resistance. The developed method should be used to enhance the corrosion resistance of common implant biomaterials by an adapted microstructure., (© 2022 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials published by Wiley Periodicals LLC.)

Background and study aims  Endoscopic submucosal dissection (ESD) with the double-balloon endoluminal intervention platform (DEIP) is a novel technique for removal of complex colon polyps (> 2 cm) or those located in anatomically difficult positions. DEIP helps create a therapeutic zone with improved visualization and stability, facilitating polyp removal. We aimed to compare the outcomes of DEIP with the conventional cap-assisted ESD (standard ESD) technique for colon polyp resection, in particular, the ability to complete the ESD procedure without resorting to hybrid ESD or piecemeal resection. Patients and methods  This was a retrospective cohort of all patients who underwent colon ESD in a single large tertiary referral center between September 2016 and October 2019. Information was collected on patient demographics and study outcomes including procedure time, rates of en bloc and curative resection, operative and postoperative complications. All patients were followed up for 1 month after the procedure. Results  111 patients were included in the study (DEIP 60, standard ESD 51). There was no statistically significant difference between mean procedures time (± SD) in the two groups, mean (81.9 ± 35.4 min standard vs. 96.4 ± 42.2 min in DEIP). Mean polyp size (± SD) was similar between the two groups (7.6 ± 6.0 cm 2 vs. 6.2 ± 5.5 cm 2 , P  = .2). There were no significant differences in en bloc and curative resection rates or operative and postoperative complications between the two techniques. Conclusion  Procedure time was similar using both techniques. However, DEIP enabled the entire procedure to be performed using the ESD technique without resorting to snare resection, which may affect the en bloc and curative resection rate. There were no significant differences in en bloc and curative resection rates between the two groups, probably due to the small sample size., Competing Interests: Competing interests Dr. Othman is a consultant for Olympus, Boston Scientific, Conmed, Abbvie and Lumendi. Dr. Othman is a consultant and an advisory board member for Lumendi. Baylor College of Medicine represented by Dr. Othman as principal investigator received a research grant ($50,000) to establish a colonic ESD registry for patients treated with DIEP. The current manuscript is investigator-initiated research that is not funded by Lumendi. Lumendi did not provide any support for generating this manuscript and no Lumendi employees or agents were involved in the manuscript preparation., (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 commecial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

Background: Congenital portosystemic shunt (cPSS) is one of the most common congenital disorders diagnosed in dogs. Hepatic encephalopathy (HE) is a frequent complication in dogs with a cPSS and is a major cause of morbidity and mortality. Despite HE been a major cause of morbidity in dogs with a cPSS, little is known about the cellular changes that occur in the central nervous system of dogs with a cPSS., Objectives: The objective of this study was to characterise the histological changes in the cerebral cortex and cerebellum of dogs with cPSS with particular emphasis on astrocyte morphology., Methods: Eight dogs with a confirmed cPSS were included in the study., Results: Six dogs had substantial numbers of Alzheimer type II astrocytes and all cases had increased immunoreactivity for glial fibrillary acidic protein in the cerebral cortex, even if there were minimal other morphological changes., Conclusions: This study demonstrates that dogs with a cPSS have marked cellular changes in the cerebral cortex and cerebellum. The cellular changes that occur in the cerebral cortex and cerebellum of dogs with spontaneously arising HE are similar to changes which occur in humans with HE, further validating dogs with a cPSS as a good model for human HE., Competing Interests: The authors have no conflicts of interest to declare., (© 2020 The Korean Society of Veterinary Science.)

Background: Salvage treatment for recurrent brain metastases (BM) of solid cancers is challenging due to the high symptomatic burden and the limited local treatment options., Methods: Patients with recurrent BM with no option for further local therapies were retrospectively identified from BM databases. Bevacizumab-based treatment was initiated as a salvage treatment. Radiological imaging before and after bevacizumab-based treatment was reevaluated for treatment response using the Response Assessment in Neuro-Oncology (RANO) BM criteria., Results: Twenty-two patients (36.4% male) with recurrent BM from breast cancer (40.9%), colorectal cancer (31.8%), or lung cancer (27.3%) were identified. Previous BM-directed therapies were radiosurgery in 16/22 (72.7%) patients, whole-brain radiotherapy in 8/22 (36.4%), and neurosurgical resection in 11/22 (50.0%). Time since BM diagnosis to initiation of bevacizumab treatment was 16.5 months. Of 22 patients 14 (63.6%) received concurrent systemic therapies. Neurological symptom improvement could be achieved in 14/22 (63.6%) and stabilization in 6/22 (27.3%) patients, resulting in a clinical benefit in 20/22 (90.9%) patients. Steroids could be reduced or stopped in 15/22 (68.2%) patients. Rate of improvement on T1-weighted imaging was 15/19 (78.9%; median reduction: -26.0% ± 32.9) and 19/20 (95%; median reduction: -36.2% ± 22.2) on T2-weighted FLAIR imaging. According to RANO-BM best response was partial response in 7/19 (36.8%), stable disease in 9/19 (47.3%), and progressive disease in 3/19 (15.7%) patients. Median CNS-specific progression-free survival was 8 months and median overall survival after initiation of bevacizumab treatment was 17 months., Conclusions: Bevacizumab-based treatment had clinically relevant intracranial activity in the vast majority of patients suffering from recurrent, symptomatic BM. The data supports a prospective clinical trial of bevacizumab as a salvage treatment in BM., (© The Author(s) 2020. Published by Oxford University Press, the Society for Neuro-Oncology and the European Association of Neuro-Oncology.)