Sediment porewaters serve as a transient organic carbon pool at the land-ocean interface.

The organic carbon (OC) cycle at the land-ocean interface is an important component of the global carbon budget, yet the processes that control the transfer, transformation, and burial of OC in these regions remain poorly understood. In this work, we examined sedimentary OC (SOC) in short core sediments, dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), and chromophoric dissolved organic matter (CDOM), as well as other solutes in sediment porewaters of the Changjiang Estuary and adjacent East China Sea (ECS) shelf. The main goal of this work is to investigate the variation of the sources and composition of different forms of carbon in estuarine sediments associated with different sedimentary regimes, to further understand the role of sediment porewater in carbon sequestration at the land-ocean interface. Concentrations of Fe2+ and Mn2+ in porewaters of the muddy sediments are much higher than those in the sandy sediments, and SO42- decreases with depth in the deep sediment layer, indicating the degradation of SOC in mobile muds is mainly driven by suboxic and/or anoxic diagenetic processes (e.g., iron-manganese reduction). The accumulation of DIC in the muddy sediment is higher compared to the sandy sediment, indicating relatively complete SOC remineralization. The DOC in porewaters of the muddy areas is mainly composed of highly degraded and low molecular weight humic-like substances (C1), whereas in the sandy area, porewater DOC is mainly composed of less degraded and high molecular weight protein-like substances (C2 and C3). The average DOC stock (28.5 t/km2) in the upper 30 cm sediment porewaters is significantly higher than that of DIC (12.5 t/km2) in sandy area, but less in muddy areas (17.0 t/km2 of DOC vs. 25.4 t/km2 of DIC). The total DOC stock in sediment porewaters of the sandy area accounted for ∼61 % of DOC stock in water column of the ECS, indicating that the porewater is an important DOC pool in the ECS. However, this DOC pool is rather transient due to its high reactivity and mobility, especially in sandy area. Nevertheless, compared with other marine environments, the carbon stock of DOC (average of 43.8 t/km2) in porewaters of stable sedimentary environments is much higher than that of DIC (average of 21.7 t/km2). This work further supports the notion that sedimentary regime plays an important role in OC cycling at the land-ocean interface and highlights the significance of sediment porewaters as a vast carbon pool in marine ecosystems.

Photodetectors Based on ZrS3/MoS2 Heterostructures.

High-performance photodetectors with the detection capability of linearly polarized light have broad applications in both military and civilian fields. Quasi-one-dimensional ZrS3 as an emerging anisotropic two-dimensional material has come under the spotlight owing to its intriguing properties. However, the performance of the ZrS3 photodetector is seriously restricted by its low responsivity. Herein, a novel high-performance photodetector based on the van der Waals ZrS3/MoS2 heterostructure is proposed. Attributed to the charge trapping-assisted photogating effect, interlayer carrier transitions, and fast spatial separation of the photogenerated electron-hole pairs, the device displays superior photoresponse characteristics ranging from the ultraviolet to the visible spectrum in terms of high responsivity up to 212 A/W, an extraordinary external quantum efficiency of 8.5 × 104%, and a prompt rise/decay time of 0.19/0.38 ms. In addition, owing to the profound birefringence and dichroism effects in ZrS3 together with strong light-matter interactions in the heterostructure, profound linear-polarization sensitivity is demonstrated with a dichroic ratio of about 2.8. Overall, this photodetector not only is integrated with the excellent properties of ZrS3 and monolayer MoS2 but also further enhances the advantages through interlayer couplings, which demonstrate the strong potential of the ZrS3-based devices for high-performance, ultrafast, and polarization-sensitive photodetection.

Serum levels of carbohydrate antigen 125 in patients with heart failure and obstructive sleep apnea syndrome: a retrospective analysis.

Background: Obstructive sleep apnea syndrome (OSAS) combined with heart failure (HF) has become a serious disease that threatens human health. Therapeutic interventions targeting OSAS have been shown to improve outcomes in patients with HF, so the identification of severe OSAS in HF is critical. Carbohydrate antigen 125 (CA125) is associated with inflammation and volume overload. The levels of CA125 are elevated in the serum of patients with HF and might be further elevated in patients with HF and OSAS. The aim of this study was to measure CA125 levels in patients with HF with and without OSAS and to analyze affecting factors. Methods: In this single-center retrospective cohort study, a total of 95 patients diagnosed with HF hospitalized in Zhongda Hospital from April 2021 to April 2022 were recruited, including 55 patients with OSAS and 40 patients without OSAS. Participants with a history of central sleep apnea syndrome, severe chronic obstructive pulmonary disease, tumors, severe infection, or who were pregnant were excluded. The histories of the participants were recorded, and laboratory examinations were performed. Binary logistic regression analysis was performed to determine the relationship between serum CA125 levels and OSAS in patients with HF. Results: The serum CA125 levels were higher in the HF + OSAS group than in the HF group (29.60 vs. 9.68 U/mL, P<0.001). According to the univariate analysis, CA125 (>35 U/mL) was significantly related to pleural effusion, acute HF, apnea-hypopnea index (AHI), left ventricular ejection fraction (LVEF) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. Finally, the AHI demonstrated statistical significance in multiple analyses (OR 1.070, 95% CI: 1.019-1.124, P=0.006). Spearman rank correlation coefficient analysis showed that CA125 was positively correlated with AHI, and Ln(CA125) (Ln is the natural logarithm based on e) gradually increased with increasing AHI (r=0.551, P<0.0001). Conclusions: The levels of CA125 were further increased in patients with HF and OSAS, and CA125 (>35 U/mL) was positively correlated with AHI. As a biomarker associated with inflammation and congestion, serum CA125 may have certain value in the diagnosis of patients with HF combined with OSAS.