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Permian–Triassic boundary sections at Baghuk Mountain (Central Iran) are investigated with respect to their lithological succession, biostratigraphy (particularly conodonts, nautiloids and ammonoids) as well as chemostratigraphy (carbon isotopes). The rock successions consist of the Late Permian Hambast Formation, the youngest Permian Baghuk Member (new name for the “Boundary Clay”) and the Early Triassic Claraia beds. Correlation of the data allows the establishment of a high-resolution stratigraphy based on conodonts with seven Changhsingian zones. Abundant ammonoids enable the separation of ammonoid assemblages with the successive Wuchiapingian genera Prototoceras, Pseudotoceras and Vedioceras, as well as the Changhsingian genera Shevyrevites, Paratirolites, Alibashites, Abichites and Arasella. Griesbachian and Dienerian ammonoids are usually poorly preserved. Nautiloids occur predominantly in the Wuchiapingian part of the section with two successive assemblages dominated by the Liroceratidae and Tainoceratidae, respectively. Numerous Early Triassic strata contain microbialites of various outer morphology and microstructure. The carbon isotope curve (δ13Ccarb) shows a continuous late Changhsingian negative excursion continuing across the Baghuk Member with the lightest values at the base of the Triassic.

The Permian–Triassic boundary section in the Aras Valley in NW Iran is investigated with respect to carbonate microfacies, biostratigraphy (particularly conodonts, nautiloids, and ammonoids), chemostratigraphy (carbon isotopes), and environmental setting. Correlation of the data allows the establishment of a high-resolution stratigraphy based on conodonts (with four Wuchiapingian, 10 Changhsingian, and three Griesbachian zones), ammonoids (with nine Changhsingian zones), and carbon isotopes; it forms the base for the reconstruction of the environmental changes before and after the end-Permian extinction event at the studied locality. In the Aras Valley section, there is no evidence for the development of anoxic conditions, associated with the end-Permian mass extinction.

Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian–Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-)sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the observed signal of carbon isotope variability. These findings put constraints on the application of Permian–Triassic carbon isotope chemostratigraphy based on whole-rock samples, which appears less refined than classical biozonation dating schemes. On the other hand, this signal of increased carbon isotope variability concurrent with the largest mass extinction of the Phanerozoic may provide information about local carbon cycling mediated by spatially heterogeneous (sub-)sea-floor microbial communities under suppressed bioturbation.

Introduction and Hypothesis: The internal iliac artery stands as the main blood supplier of the pelvis, serving as the primary source of blood for the pelvic viscera while also nourishing the musculoskeletal framework within. The arterial anatomy of the pelvis exhibits a vast array of variations, especially regarding the branching pattern of the internal iliac arteries. The posterior division of the internal iliac artery (PDIIA) may also have variable topography, especially regarding the location of its origin in the pelvic region., Methods: A retrospective study was carried out to determine the anatomical variations, prevalence, and morphometric data of the PDIIA and its branches. A total of 75 computed tomography angiographies were analyzed., Results: The most prevalent branch of the PDIIA was the superior gluteal artery, as it was present in 114 of the studied cases (77.03%). The median diameter of the PDIIA at its origin was 6.66 mm. The median cross-sectional area of the PDIIA at its origin was set to be 34.59 mm 2 ., Conclusion: Our study highlights the critical significance of understanding the PDIIA and its branches in surgical interventions aimed at managing pelvic hemorrhage. The present study provides valuable insights into the precise localization and characteristics of the PDIIA and its branches, which are essential for surgical procedures targeting specific vessels to control bleeding effectively. Owing to the high level of variability of the branching pattern of the PDIIA, a novel classification system consisting of six types was created., Competing Interests: Declarations. Conflicts of Interests: The author(s) declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Informed Consent: Not applicable. Bioethical Committee: The research protocol was submitted for evaluation and approved by the Jagiellonian University Bioethical Committee, Cracow, Poland (1072.6120.254.2022)., (© 2024. The Author(s).)

Knowledge about the anatomy of the submental artery (SA) is of immense importance when performing plastic and reconstructive procedures. A retrospective study was performed to analyze the topographic anatomy of the SA. The measurements were performed on 80 consecutive patients who underwent head and neck computed tomography angiography (CTA). The SA was present in 131 out of 137 hemifaces (95.6%). The vessel originated from the facial artery in all cases (100.0%). Moreover, the SA was found to have 0-4 branches. However, most commonly, the said artery had no branches of considerable size (51.1%). Due to the high variability of the course of the said artery, the authors of the present study created a novel classification system presenting the most prevalent courses of the SA in the submental region. The current study utilized 131 hemifaces of 80 (CTA) to create a heat map of the SA, illustrating its precise origin and course in the submental region. The findings of this study could assist surgeons in developing a mental map of the arterial anatomy of the submental region, potentially improving the efficiency of localizing the SA and reducing the risk of complications during plastic and reconstructive procedures., (© 2023 American Association of Clinical Anatomists and British Association of Clinical Anatomists.)

Background: The superior gluteal artery (SGA) is the largest, terminating branch of the internal iliac artery (IIA). Knowledge about the anatomy of the SGA is extremely important when performing numerous reconstructive and endovascular procedures., Materials and Methods: The results of 75 consecutive patients who underwent pelvic computed tomography angiography (CTA) were analysed., Results: A total of 145 SGAs were analysed. The origin variation of each SGA was deeply analysed. Type O1 occurred in 79 SGA (56.4%). Furthermore, analogously, branching pattern types were also established. Initially 19 branching variations were evaluated, of which types 1-7 constituted 76.5%. The median SGA length was set to be 54.88 mm (LQ = 49.63; HQ = 63.26). The median SGA origin diameter, in cases of SGA originating from PDIIA, was set to be 6.27 mm (LQ = = 5.56; HQ = 6.87)., Conclusions: The origin of the said artery showed a low grade of variability, and the most prevalent origin type of the SGA was similar to the one presented by the major anatomical textbooks, namely, the PDIIA. However, the branching pattern of the SGA was highly variable. To present the anatomy of the SGA in a clear and straight-forward way, novel classification systems of the origin and branching patterns were made. Furthermore, the morphometric properties of the branches of the PDIIA were analysed. It is hoped that the results of the present study may be useful for physicians performing numerous reconstructive and endovascular procedures.

Background: The inferior gluteal artery (IGA) is a large terminal branch of the anterior division of the internal iliac artery (ADIIA). There is a significant lack of data regarding the variable anatomy of the IGA., Materials and Methods: A retrospective study was conducted to establish anatomical variations, their prevalence and morphometrical data on IGA and its branches. The results of 75 consecutive patients who underwent pelvic computed tomography angiography were analysed., Results: The origin variation of each IGA was deeply analysed. Four origin variations have been observed. The most common type O1 occurred in 86 of the studied cases (62.3%). The median IGA length was set to be 68.50 mm (lower quartile [LQ]: 54.29; higher quartile [HQ]: 86.06). The median distance from the origin of the ADIIA to the origin of the IGA was set to be 38.22 mm (LQ: 20.22; HQ: 55.97). The median origin diameter of the IGA was established at 4.69 mm (LQ: 4.13; HQ: 5.45)., Conclusions: The present study thoroughly analysed the complete anatomy of the IGA and the branches of the ADIIA. A novel classification system for the origin of the IGA was created, where the most prevalent origin was from the ADIIA (type 1; 62.3%). Furthermore, the morphometric properties (such as the diameter and length) of the branches of the ADIIA were analysed. This data may be incredibly useful for physicians performing operations in the pelvis, such as interventional intraarterial procedures or various gynaecological surgeries.

Background: The objective of this meta-analysis was to investigate the anatomical variations of the mandibular lingula (ML) and its relationship with surrounding anatomical structures. Understanding such variations is crucial to help determine the site and depth of a successful inferior alveolar nerve (IAN) anaesthetic block as well as a safe area for oral and maxillofacial invasive procedures to minimise the risk of neurological or haematological damage to the inferior alveolar nerve., Materials and Methods: A systematic search was conducted in which all studies were searched on the anatomy of ML. Major medical databases such as PubMed, Scopus, Embase, Web of Science, Google Scholar, and Cochrane Library were searched., Results: All the results were based on a total of 4694 subjects. The overall height of the ML was found to be 8.17 mm (SE = 0.22). The triangular type of ML was found to be the most common. The pooled prevalence of this variation was found to be 29.33% (LCI = 23.57%; HCI = 35.24%). The pooled prevalence of the nodular type was found to be 27.99% (LCI = 22.64%; HCI = 33.67%)., Conclusions: The present meta-analysis provides clinically relevant information regarding the shape, location, and height variations of the ML. Understanding such variations of the ML is crucial when performing malocclusion correction procedures that require the ML as a landmark, namely sagittal split ramus osteotomy, and intraoral vertical ramus osteotomy. Furthermore, effective anaesthetic blocks during oral and maxillofacial procedures can be accomplished with a higher success rate if the correct site of injection is identified. The possible locations of the ML should be considered to determine the location of the mandibular foramen and, therefore, the inferior alveolar bundle to prevent motor, sensory, or perfusion pathology during maxillofacial and oral procedures of the lower jaw.

The main objective of the present study was to clarify the anatomical characteristics of the GDA. In order to fulfill this objective, novel classification systems of both the origin and branching pattern of the said vessel were created. Being aware of the variable anatomy of the GDA is of great importance when performing hepatopancreaticobilliary procedures. The results of 75 consecutive patients who underwent abdomen computed tomography angiography (CTA) were analyzed. A total of 74 GDA were analyzed. Of these, 42 were from women (56.8%) and 32 were from men (43.2%). The most common direction of origin of the GDA was inferior (n = 38; 51.4%). The origin variation of each GDA was deeply analyzed. Initially, eight types of origin variations were evaluated, of which types 1-3 constituted 83.8%. Furthermore, analogously, branching pattern types were also established. Initially, 11 branching variations were evaluated, of which types 1-3 constituted 87.8%. The GDA is subject to numerous variations, both in the origin and in the branching pattern of the vessel. In order to clarify the anatomical characteristics of this vessel, novel classifications of the origin and branching patterns were made, presenting the most frequent patterns. Our results may be of great use for surgeons performing hepatopancreaticobilliary surgeries, such as the Whipple procedure or vascular reconstructions after cholangiocarcinoma resections. Being aware of the anatomical variations of relevant structures associated with a surgical procedure may help reduce potential intraoperative and/or postoperative complications., (© 2023 American Association of Clinical Anatomists and British Association of Clinical Anatomists.)

During the earliest Triassic microbial mats flourished in the photic zones of marginal seas, generating widespread microbialites. It has been suggested that anoxic conditions in shallow marine environments, linked to the end-Permian mass extinction, limited mat-inhibiting metazoans allowing for this microbialite expansion. The presence of a diverse suite of proxies indicating oxygenated shallow sea-water conditions (metazoan fossils, biomarkers and redox proxies) from microbialite successions have, however, challenged the inference of anoxic conditions. Here, the distribution and faunal composition of Griesbachian microbialites from China, Iran, Turkey, Armenia, Slovenia and Hungary are investigated to determine the factors that allowed microbialite-forming microbial mats to flourish following the end-Permian crisis. The results presented here show that Neotethyan microbial buildups record a unique faunal association due to the presence of keratose sponges, while the Palaeotethyan buildups have a higher proportion of molluscs and the foraminifera Earlandia . The distribution of the faunal components within the microbial fabrics suggests that, except for the keratose sponges and some microconchids, most of the metazoans were transported into the microbial framework via wave currents. The presence of both microbialites and metazoan associations were limited to oxygenated settings, suggesting that a factor other than anoxia resulted in a relaxation of ecological constraints following the mass extinction event. It is inferred that the end-Permian mass extinction event decreased the diversity and abundance of metazoans to the point of significantly reducing competition, allowing photosynthesis-based microbial mats to flourish in shallow water settings and resulting in the formation of widespread microbialites., Competing Interests: The authors have no conflict of interest to declare., (© 2019 The Authors. The Depositional Record published by John Wiley & Sons Ltd on behalf of International Association of Sedimentologists.)

Alkylresorcinols (ARs) are phenolic lipids that are present in high amounts in the bran layer of different cereals. Rye samples, cultivar Hazlet, and a white rye genotype, RT202, were analyzed for their antioxidant properties and AR content and composition, based on six fractions of the bran, where 1 was the outermost fraction and 6 was the bran fraction closest to the endosperm. Gas chromatography-mass spectrometry (GC-MS) analysis demonstrated that the most commonly found AR homologue in Hazlet rye is C19:0 and that the total amount of ARs decreases from the outermost to innermost fractions. The antioxidant activity using oxygen radical absorbance capacity (ORAC) for both white rye genotype RT202 and Hazlet brans was determined to decrease from the outermost fraction (136.05 μmol TE/g for Hazlet fraction 1 and 186.57 μmol TE/g for white rye genotype RT202 fraction 1) to the innermost fraction (9.84 μmol TE/g for Hazlet fraction 6 and 78.75 μmol TE/g for white rye genotype RT202 fraction 2). A positive relationship was seen with GC-MS results. Treatment of PC-12 AC cells with Hazlet fraction 1 increased mitochondrial biogenesis as determined using mitochondrial fluorescent dyes. In the presence of a prooxidant (AAPH), PC-12 AC cells were better protected from free radical attack when treated with Hazlet fraction 1 than with all other bran fractions. The results suggest that higher AR content in bran fractions confers antioxidant protection against free radical damage.