Microbial sulfate reduction regulated by relative sea level change in a Pleistocene – Holocene sedimentary record: Insights from Loch Duart, Scotland, UK

A Pleistocene–Holocene-aged sediment core recovered near Loch Duart, located in the coastal Assynt region of NW Scotland, UK, provides new insight into the relationship between the sulfur isotope composition of iron sulfides (pyrite) and organic sulfur under rapidly changing environmental conditions. Since the Late Glacial period, shifts in local marine connectivity at Loch Duart have been driven by the competition between two fundamental Earth surface processes: eustatic sea level rise due to post-glacial meltwater contributions since the Last Glacial Maximum and relative sea level (RSL) fall associated with glacial isostatic rebound. These processes, imprinted on the sedimentary record, have been evaluated via lithology, microfossil assemblages, elemental analysis, and isotopic measurements. Over the last 17 kyr, Loch Duart has transitioned from (1) marine conditions, when eustatic rise due to deglaciation exceeded glacial isostatic rebound, to (2) non-marine conditions, where land uplift caused by isostatic rebound exceeded eustatic rise, to (3) marine conditions, as the eustatic contribution outpaced isostatic rebound, followed by (4) brackish-water conditions, as the eustatic contribution reduced while glacial isostatic uplift continued, with marine inundation limited to part of the tidal cycle at the present day.Here, we evaluate marked perturbations in the local sulfur (S) cycle related to the aforementioned environmental changes. The marine interval coincides with relatively stable and low δ34Ssulfide values (average ∼ −27.2 ‰), the non-marine interval records an abrupt positive δ34Ssulfide excursion of over 30 ‰ (average ∼ 9 ‰), and the brackish interval preserves intermediate values (average ∼ −16.2 ‰). The δ34Sorg values shift sympathetically with δ34Ssulfide, although the magnitude of δ34Sorg change is nominal by comparison, particularly during the transition from freshwater to marine facies. As expected, marine and brackish sections preserve higher δ34Sorg values than coeval δ34Ssulfide. Interestingly, this relationship is reversed in the freshwater facies, where sulfides are 34S-enriched relative to organic S by as much as 20 ‰, suggesting that RSL modulates the isotopic composition of non-pyrite phases in the bulk S pool. We hypothesize that this inverse relationship (δ34Sorg < δ34Ssulfide) may arise from a spatial decoupling of pyrite and organic S formation within the water column and/or sediments in a system with low sulfate concentrations. Evaluating shifts in the local S-cycle associated with RSL changes allows for a novel comparison between S and osmium isotope records, demonstrating that these proxies may have joint applications for paleoenvironmental investigations in shallow coastal systems. We offer new perspectives on the interplay between eustasy, RSL, and the S-cycle by assessing these relationships in a coastal isolation basin

Radioisotopic chronology of Ocean Anoxic Event 1a: Framework for analysis of driving mechanisms.

The timing, tempo, and causative mechanisms of Ocean Anoxic Event 1a (OAE1a), one of several such abrupt perturbations of the Mesozoic global carbon cycle, remain uncertain. Mudstones interbedded with tuffs in Hokkaido, Japan preserve carbon and osmium isotope shifts recording OAE1a. U-Pb zircon ages of tuffs constrain the OAE1a onset to 119.55 +0.072/-0.079 million years ago (Ma) and its duration to 1116 +87/-93 thousand years (kyr). Isotopic excursions of osmium followed by carbon that mark the rapid onset of OAE1a each lasted ~115 kyr. Critically, the occurrence of index fossil Leupoldina cabri in the Hokkaido OAE1a section, which also caps and thus postdate Ontong Java Plateau (OJP) basalts, has a U-Pb zircon age of ~118.7 to 118.4 Ma. Therefore, OJP volcanism remains a probable source of unradiogenic osmium and light carbon and a causative mechanism of OAE1a

Patients&apos; survival after free flap reconstructive surgery of head and neck squamous cell carcinoma : a retrospective multicentre study

Head and neck squamous cell carcinoma of the (HNSCC) represents approximately 5% of malignant tumours in Italy. HNSCC are commonly treated with surgery or radiotherapy, or a combination of such therapies. The objectives of treatment are maximum cure rate balanced with organ preservation, restoration of form and function, reduction of morbidities and improvement or maintenance of the patient's quality of life. Immediate reconstructive surgery: local, regional or free flaps are now widely advised in the treatment of these patients. Microsurgical transfer requires expertise, is time and resource consuming, and as a whole requires substantial costs. These considerations introduce some concerns about the wide or indiscriminate use of free flap reconstructive surgery. When considering cost-benefit outcomes of such treatment, the main objective is undoubtedly, survival. This data is underreported in the current literature, whereas functional outcomes of free flaps have been largely diffused and accepted. This study collects data from 1178 patients treated with free flap reconstructive surgery following ablation of HNSCC in a group of Italian tertiary hospitals, all members of the Head &amp; Neck Group affiliated with the Italian Society of Microsurgery. According to many authors, free flap surgery for HNSCC seems to be a beneficial option for treatment even in terms of survival

Studi di intervento nel centro storico di Sacile

Catalogo della mostra dei progetti per la ridefinizione architettonica e urbanistica delle principali piazze e degli spazi pubblici per le citt\ue0 di Sacile, Salisburgo e Pirano

Clear as mud: Clinoform progradation and expanded records of the Paleocene-Eocene Thermal Maximum

Abstract The mid-Atlantic coastal plain (eastern United States) preserves high-resolution records of the Paleocene-Eocene Thermal Maximum (PETM) and attendant carbon isotope excursion (CIE), though preservation is highly variable from site to site. Here, we use a dip transect of expanded (as much as 15 m thick) PETM sections from the New Jersey coastal plain to build a cross-shelf PETM depositional model that explains the variability of these records. We invoke enhanced delivery of fine-grained sediments, due to the rapid environmental changes associated with this hyperthermal event, to explain relatively thick PETM deposits. We utilize δ13Cbulk, percent CaCO3, and percent coarse fraction (&amp;gt;63 μm) data, supported by biostratigraphic records, to correlate sites along a paleoslope dip transect. Updip cores from Medford, New Jersey, preserve expanded sections of the initiation of the PETM and the earliest portion of the CIE. Medial sites (Wilson Lake, Millville) preserve an expanded CIE body, and downdip Bass River records the CIE recovery. We interpret this pattern to reflect the progradation of clinoform foresets across the paleoshelf via fluid mud, similar to modern high-sediment-supply rivers and adjacent muddy shelves (e.g., the Amazon, Mahakam [Indonesia], and Ayeyarwady [Myanmar] Rivers). Our subaqueous-clinoform delta model explains the pattern of the CIE records and provides a framework for future PETM studies in the region.</jats:p

The Role of Native T1 and T2 Mapping Times in Identifying PD-L1 Expression and the Histological Subtype of NSCLCs

We investigated the association of T1/T2 mapping values with programmed death-ligand 1 protein (PD-L1) expression in lung cancer and their potential in distinguishing between different histological subtypes of non-small cell lung cancers (NSCLCs). Thirty-five patients diagnosed with stage III NSCLC from April 2021 to December 2022 were included. Conventional MRI sequences were acquired with a 1.5 T system. Mean T1 and T2 mapping values were computed for six manually traced ROIs on different areas of the tumor. Data were analyzed through RStudio. Correlation between T1/T2 mapping values and PD-L1 expression was studied with a Wilcoxon–Mann–Whitney test. A Kruskal–Wallis test with a post-hoc Dunn test was used to study the correlation between T1/T2 mapping values and the histological subtypes: squamocellular carcinoma (SCC), adenocarcinoma (ADK), and poorly differentiated NSCLC (PD). There was no statistically significant correlation between T1/T2 mapping values and PD-L1 expression in NSCLC. We found statistically significant differences in T1 mapping values between ADK and SCC for the periphery ROI (p-value 0.004), the core ROI (p-value 0.01), and the whole tumor ROI (p-value 0.02). No differences were found concerning the PD NSCLCs

Patients' survival after free flap reconstructive surgery of head and neck squamous cell carcinoma: a retrospective multicentre study

Head and neck squamous cell carcinoma of the (HNSCC) represents approximately 5% of malignant tumours in Italy. HNSCC are commonly treated with surgery or radiotherapy, or a combination of such therapies. The objectives of treatment are maximum cure rate balanced with organ preservation, restoration of form and function, reduction of morbidities and improvement or maintenance of the patient's quality of life. Immediate reconstructive surgery: local, regional or free flaps are now widely advised in the treatment of these patients. Microsurgical transfer requires expertise, is time and resource consuming, and as a whole requires substantial costs. These considerations introduce some concerns about the wide or indiscriminate use of free flap reconstructive surgery. When considering cost-benefit outcomes of such treatment, the main objective is undoubtedly, survival. This data is underreported in the current literature, whereas functional outcomes of free flaps have been largely diffused and accepted. This study collects data from 1178 patients treated with free flap reconstructive surgery following ablation of HNSCC in a group of Italian tertiary hospitals, all members of the Head & Neck Group affiliated with the Italian Society of Microsurgery. According to many authors, free flap surgery for HNSCC seems to be a beneficial option for treatment even in terms of survival