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Drift limits are useful thresholds; during design or retrofitting analyses, engineers can compare the expected behaviour of a structure to drift limits that predict when the structure will reach a certain condition. This helps ensure that structures satisfy specified performance goals when exposed to certain hazards. Masonry walls are susceptible to damage from lateral in‐plane actions such as wind or earthquake loading; ensuring that in‐plane drift remains sufficiently small will help limit this damage. Drift limits based on crack‐based damage are scarce, however, with DS1 limits being extrapolated from higher damage grades based on structural strength capacity or ductility. In this work, crack‐based damage is evaluated on a multitude of full‐scale experimental walls surveyed with digital image correlation. This method observes the initiation and propagation of cracking. Cyclically incremental in‐plane tests provide a range of drift‐damage relationships. These are explored with machine learning to determine influential predictors and ultimately establish drift limits for light damage. Two types of brick masonry are explored: fired‐clay and calcium‐silicate. For the latter, light damage begins at an in‐plane drift of 0.5 mm/m and can extend to 4.8 mm/m (or 0.48%) for the former before the masonry surpasses light damage and reaches structural damage grades. In comparison to drift limits set by other authors and (international) guidelines to characterise light damage, significant damage, or the ultimate capacity of masonry walls, the resulting drift limits for light damage from this work are set directly on the basis of experiments and are in good agreement with other authors. Most importantly, all the consulted values for ultimate capacity are much larger than the upper threshold for light damage determined herein, with limits for significant damage in the same order of magnitude. This result verifies the accuracy of the experimental crack‐based characterisation used to establish the drift thresholds. [ABSTRACT FROM AUTHOR]

Background: Pancreatic ductal adenocarcinoma (PDAC) typically occurs in an older patient population. Yet, early-onset pancreatic cancer (EOPC) has one of the fastest growing incidence rates. This study investigated the influence of age and tumor location on postoperative morbidity and mortality in a large, real-world dataset., Methods: Patients with confirmed PDAC undergoing pancreatic surgery between 01/01/2014 and 31/12/2019 were identified from the German StuDoQ|Pancreas registry. After categorization into early- (EOPC; < 50 years), middle- (MOPC; 50 -70 years), and late-onset (LOPC; > 70 years), and stratification into pancreaticoduodenectomy (PD) or distal pancreatectomy (DP), differences in morbidity and mortality as well as clinicopathologic parameters were analyzed., Results: In total, 3011 patients were identified. No difference in the occurrence of postoperative pancreatic fistula (POPF), postpancreatectomy hemorrhage (PPH) or delayed gastric emptying (DGE) between different age groups and resection techniques was detected. However, in patients undergoing PD, major complications (Clavien-Dindo ≥ 3a) were observed more frequently in LOPC (30,7%) than in MOPC (26,2%) and EOPC (16,9%; p < 0,01). Mortality almost tripled from EOPC (2,4%) to MOPC (3,6%) to LOPC (6,6%, p < 0,01) and significantly higher failure to rescue (FTR) rates could be observed (EOPC 14,3%, MOPC 13,6%; LOPC 21,6%; p < 0,05). In centers with DGAV certification for pancreatic surgery, the risk of complications was significantly decreased in PD (OR 0,79; 95% CI 0,65-0,94; p = 0,010)., Conclusion: Age has a pronounced impact on the perioperative outcomes after pancreatic resections of PDAC. This effect is more prevalent in PD compared to DP. Pancreatic surgery-specific complications, such as POPF, DGE or PPH do not occur more frequently in the elderly. Overall, the risk of major complications and mortality increases in elderly patients mainly secondary to higher FTR rates., Competing Interests: Declarations. Ethics approval and consent to participate: As irreversibly anonymized data was retrospectively analyzed, the present study was deemed for exemption by the current regulations of the medical faculty of the LMU University of Munich (Ethikkommission der Medizinischen Fakultät der LMU München, Pettenkoferstrasse 8, 80336 München). All methods were carried out in accordance with relevant guidelines and regulations and for StuDoQ data collection, informed consent to participate was obtained from all of the participants in the study. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Purpose: This study aimed to evaluate the dental and skeletal stability one year after Miniscrew-Assisted Rapid Palatal Expansion (MARPE) by using 3D image data., Methods: Patients with transverse maxillary deficiency from the age of 16 onwards were enrolled consecutively in this prospective longitudinal cohort study. The MARPE appliance was digitally and individually designed and fabricated. Cone-beam computed tomography (CBCT) scans and intra-oral scans (IOS) were acquired before the start of MARPE treatment (T0), immediately after active expansion (T1) and one-year post-expansion (T2). Nasal floor width (NFW), palatal alveolar width at the first molar (M1) and first premolar (P1) (PAW), nasal cavity width (NCW), intermolar width (IMW) and interpremolar width (IPW) were measured to assess the immediate (ΔT0-T1) and net (ΔT0-T2) skeletal and dentoalveolar expansion and relapse (ΔT1-T2). Potential correlations with age, sex and midpalatal suture maturation (MSM) stage were also investigated., Results: Thirty-one patients (6 men, 25 women, mean age: 26.2 years) were included. The mean follow-up time (T0-T2) was 12.2 months. The initial NFW increase demonstrated a relapse of 0.6 ± 1.2 mm, or 11.6% of the initial expansion (p < 0.01). Expansion at the alveolar level remained stable during the follow-up. IPW also remained stable during the follow-up (4.2 ± 1.3 mm at T1; 4.4 ± 2.6 mm at T2). IMW exhibited a relapse of 3.8 ± 2.1 mm, or 60.2% of the initial expansion (p < 0.001) during T1-T2. There was no statistically significant correlation between stability and age, sex and MSM stage., Conclusions: MARPE is an effective therapy for the correction of transverse maxillary discrepancy in late adolescents and adults, achieving a clinically stable skeletal outcome one year after expansion., Competing Interests: Declarations. Ethical approval: The study was approved by the Radboud University Medical Center Institutional Review Board (IRB no. 2019–5898). Consent to participate: A written informed consent was obtained from all study participants. Consent to publish: The authors affirm that human research participants provided informed consent for publication of the images in Figs. 1 and 2. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)