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The relative apportion of above and below ground carbon sources is known to be an important factor in soil organic matter formation. Although lignin is the most abundant aromatic plant material in the terrestrial biosphere, our understanding of lignin source contributions to soil organic matter (SOM) is limited due to the complex molecular structure and analysis of lignin. In this study, we novelly apply the dual isotopic analysis (δ 13 C and δ 2 H values) of lignin methoxy groups (LMeO) with the Bayesian mixing model, MixSIAR, to apportion lignin sources in two contrasting soil types, a podzol and a stagnosol. Results of the isotopic analysis of LMeO demonstrate the ability of δ 2 H LMeO values to discriminate between above and below ground lignin sources, while δ 13 C LMeO values discriminated between photosynthesising and non-photosynthesising tissues. In the stagnosol subsurface horizons, a decreasing proportion of the leaf litter lignin was observed with increasing organic matter degradation, cumulating in the Ah horizon being dominated by lignin from roots. The podzol sites indicated a similar reduction in leaf litter lignin with an increase in organic matter degradation and depth. However, the Ah horizon was shown to accumulate lignin from the above ground woody material. Furthermore, given the significant abundance of LMeO groups in the terrestrial biosphere and the extremely depleted δ 13 C LMeO values in leaf litter, we employed a mass balance approach to determine the extent in which the 13 C bulk enrichment generally associated with isotopic fractionation during organic matter decomposition can be attributed to the shift in lignin sources. Analysis reveals that 14 % and 11 % of bulk 13 C enrichment can be attributed to the transition in LMeO sources from leaf litter to roots in the stagnosol and podzol, respectively. Thus, models relying on 13 C enrichment with depth as an indicator of carbon turnover may be partially overestimating rates., Competing Interests: Declaration of competing interest The authors have no relevant financial or nonfinancial interests to disclose., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Women with hereditary fibrinogen disorders (HFDs) seem to be at an increased risk of adverse obstetrical outcomes, but epidemiologic data are limited., Objectives: We aimed to determine the prevalence of pregnancy complications; the modalities and management of delivery; and the postpartum events in women with hypofibrinogenemia, dysfibrinogenemia, and hypodysfibrinogenemia., Methods: We conducted a retrospective and prospective multicentric international study., Results: A total of 425 pregnancies were investigated from 159 women (49, 95, and 15 cases of hypofibrinogenemia, dysfibrinogenemia, and hypodysfibrinogenemia, respectively). Overall, only 55 (12.9%) pregnancies resulted in an early miscarriage, 3 (0.7%) resulted in a late miscarriage, and 4 (0.9%) resulted in an intrauterine fetal death. The prevalence of live birth was similar among the types of HFDs (P = .31). Obstetrical complications were observed in 54 (17.3%) live birth pregnancies, including vaginal bleeding (14, 4.4%), retroplacental hematoma (13, 4.1%), and thrombosis (4, 1.3%). Most deliveries were spontaneous (218, 74.1%) with a vaginal noninstrumental delivery (195, 63.3%). A neuraxial anesthesia was performed in 116 (40.4%) pregnancies, whereas general or no anesthesia was performed in 71 (16.6%) and 129 (44.9%) pregnancies, respectively. A fibrinogen infusion was administered in 28 (8.9%) deliveries. Postpartum hemorrhages were observed in 62 (19.9%) pregnancies. Postpartum venous thrombotic events occurred in 5 (1.6%) pregnancies. Women with hypofibrinogenemia were at an increased risk of bleeding during the pregnancy (P = .04)., Conclusion: Compared with European epidemiologic data, we did not observe a greater frequency of miscarriage, while retroplacental hematoma, postpartum hemorrhage, and thrombosis were more frequent. Delivery was often performed without locoregional anesthesia. Our findings highlight the urgent need for guidance on the management of pregnancy in HFDs., Competing Interests: Declaration of competing interests A.C. reports grants and fees paid to his institution from CSL Behring, Octapharma, Sobi, LFB, Takeda, and Novo Nordisk. A.L. reports grants and fees from Octapharma and LFB. C.L.B reports receiving grants and fees from LFB, Octapharma, CSL Behring, and Novo Nordisk. M.F. reports grants and fees from LFB. All other authors have no competing interests to disclose., (Copyright © 2023 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)