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Mass movements and delta collapses are significant sources of tsunamis in lacustrine environments, impacting human societies enormously. Paleotsunamis studies play an essential role in understanding historical events and their consequences, along with their return periods. This study investigates a paleotsunami induced by a subaqueous mass movement during the Younger Dryas to Early Holocene transition, ca. 11,700 years ago in Lake Aiguebelette (NW Alps, France). Utilizing high‐resolution seismic and bathymetric surveys associated with sedimentological, geochemical, and magnetic analyses, we uncovered a paleotsunami triggered by a seismically induced mass transport deposit. Numerical simulations of mass movement have been conducted using a visco‐plastic Herschel‐Bulkley rheological model and corresponding tsunami wave modeled with dispersive and nondispersive models. Our findings reveal for the first time that dispersive effects may be negligible for subaqueous landslides in a relatively small lake. This research reconstructs a previously unreported paleotsunami event and enhances our understanding of tsunami dynamics in lacustrine environments. Plain Language Summary: This study explores an ancient landslide and its ability to potentially generate a tsunami. This event took place in Lake Aiguebelette, located in the NW Alps, France. By applying advanced underwater mapping techniques and computer modeling, we were able to reconstruct the origins and impact of this underwater prehistoric landslide. Our work revealed that this underwater landslide may have triggered a significant tsunami wave. These findings are crucial as they provide new insights into the dynamics of such geological events in lake environments, enhancing our understanding of their potential impacts and aiding in the preparation for future similar hazards. Key Points: Uncovered a 11,700‐year‐old subaqueous landslide‐induced paleotsunami in Lake Aiguebelette (NW Alps, France)Numerical model is constrained to reproduce the available geological dataFound dispersion effects to be of minimal importance in the modeling of this historical tsunami event [ABSTRACT FROM AUTHOR]

A low temperature hydrogen borrowing approach to generate secondary amines using benzimidazole-based N-heterocyclic carbene (BNHC) ruthenium complexes is reported. A series of the piano-stool complexes of the type [(η6-p-cymene)(BNHC)RuCl2] (1a-g) were synthesized via one-pot reaction of the NHC salt precursor, Ag2O, and [RuCl2(p-cymene)]2 and characterized using conventional spectroscopic techniques. The geometry of two precursors, [(η6-p-cymene)(Me4BnMe2BNHCCH2OxMe)RuCl2] (1f) and [(η6-pcymene)(Me5BnMe2BNHCCH2OxMe)RuCl2] (1g), was studied by single crystal X-ray diffraction. These catalysts were found to dehydrogenate alcohols efficiently at temperatures as low as 50 °C to allow Schiff-base condensation and subsequent imine hydrogenation to afford secondary amines. Notably, this ruthenium-based procedure enables the N-alkylation of aromatic and heteroaromatic primary amines with a wide range of primary alcohols in excellent yields of up to 98%. The present methodology is green and water is liberated as the sole byproduct. [ABSTRACT FROM AUTHOR]

Background:  Total knee arthroplasty (TKA) may result in significant blood loss, but it is an effective and affordable treatment for severe osteoarthritis in the knees. While intravenous (IV) tranexamic acid (TXA) is a commonly used technique, intraarticular (IA) TXA has just recently started to gain traction in joint replacement procedures. The purpose of this research was to examine the mean postoperative hemoglobin concentration in order to assess the effectiveness of TXA administered IV vs IA after TKA., Objective: To assess the effectiveness of intraarticular TXA against intravenous administration., Materials and Methods: The six-month randomized controlled experiment was started from October 5, 2022, to April 4, 2023, at "the Orthopedics Department of Sir Ganga Ram Hospital in Lahore". The experiment included 60 patients undergoing TKA, ranging in age from 30 to 70. All members of the surgical team, including the supervisor (a consultant surgeon), assistants, and researchers, were present throughout the surgery. A high, thigh tourniquet was employed in every case, and a medial parapatellar technique was performed as well. Before the tourniquet was inflated, individuals in the intravenous group received 1 g of TXA intravenously 15-30 minutes beforehand. In the IA group, the "patient received an injection of 2 g of TXA in a 20 mL solution" straight into the joint after the prosthesis was implanted and secured. Data were analyzed using SPSS (version 26), with numerical data (age, BMI, surgical length, and hemoglobin levels) presented as mean ± SD and categorical factors (gender, American Society of Anesthesiologists (ASA) class, anatomical side) shown as frequency and percentage. The mean postoperative hemoglobin levels were compared between groups using an independent sample t-test, with data stratified by various factors and p ≤ 0.05 considered significant., Results: There were 60 patients in this study, ranging in age from 30 to 70. The mean±SD age was 48.73±10.35 years. Patients' mean BMI was 25.51±4.48 kg/m², with representation across underweight, normal, overweight, and obese categories. The procedure took 173.10±32.61 minutes. The overall postoperative hemoglobin concentration was significantly higher in the IA TXA group (12.12±1.32 g/dL) compared to the IV TXA group (11.11±1.10 g/dL), with a p-value of 0.02. Additionally, when stratified by age, the IA TXA group consistently demonstrated higher postoperative hemoglobin levels across all age brackets, with significant differences observed in the 51-60 years (p = 0.001) and 61-70 years (p = 0.011) groups. Gender-based comparisons showed that IA TXA was associated with higher postoperative hemoglobin levels for both males (p < 0.05) and females (p < 0.05) compared to IV TXA., Conclusion: This study demonstrates that IA administration of TXA is more effective in maintaining higher postoperative hemoglobin concentrations compared to IV TXA in patients undergoing TKA. The IA TXA group consistently achieved significantly higher hemoglobin levels across various age groups and both genders, indicating superior efficacy in reducing blood loss associated with TKA. These findings suggest that IA TXA could be a preferable alternative to IV TXA for enhancing postoperative hemoglobin recovery and potentially improving patient outcomes in knee arthroplasty procedures., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Institutional Review Committee of the College of Physicians and Surgeons Pakistan (CPSP) issued approval CPSP/REU/OSG-2021-059-2658. The ethical review committee of the College of Physicians and Surgeons Pakistan (CPSP) approved the study, which was carried out in compliance with ethical guidelines, under reference number CPSP/REU/OSG-2021-059-2658, dated September 15, 2022. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Aslam et al.)