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Density is an important parameter for both geological research and geophysical exploration. However, for model-driven seismic inversion methods, high-fidelity density inversion is challenging due to seismic wave traveltime insensitivity to density and crosstalk that density has with velocity. To circumvent the challenge of density inversion, some inversion methods treat density as a constant value or derive density from velocity through empirical equation. On the other hand, deep learning approaches are completely driven by data and have strong target-oriented characteristics, offering a new way to solve multiparameter coupling problems. Nevertheless, the accuracy of the inversion results of data-driven algorithms is directly related to the amount and diversity of the training data, and thus, they lack the universality of model-driven algorithms. To achieve accurate density inversion, we propose a simultaneous inversion algorithm for velocity and density that combines the advantages of data- and model- driven approaches: A neural network model (U-T), combining the U-net and Transformer architectures, is proposed to construct non-linear mappings between seismic data as inputs and the velocity and density as predictions. Next, the model-driven inversion algorithm uses the U-T prediction as the initial model to obtain the final accurate solution. In the model-driven module, envelope-based sparse constrained deconvolution is used to obtain full-band seismic data, while a variable dominant frequency full waveform inversion algorithm is used to perform multiscale inversion, ultimately leading to accurate inversion results of velocity and density. The performance of the algorithm on the Sigsbee2A and Marmousi models demonstrates its effectiveness. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) is a potential wide band gap semiconductor, but its high photoelectron-hole pairs recombination rate and poor light absorption ability limit its application to photoelectrochemical (PEC) water oxidation. To solve these problems, in this work, a reasonable band structure engineering was carried out on ZnO nanorod arrays (ZnO NRAs) with the co-decoration of nitrogen doped g-C3N4 (NCN) and carbon quantum dot (CQDs) solution. Narrow band gap NCN was loaded onto the surface of ZnO NRAs by a simple spin coating method, and then CQDs were modified on the ZnO/NCN NRAs. The composite photoanode of ZnO/NCN/CQDs NRAs was finally obtained. The PEC performance of the composite photoanode reaches 1.82 times that of the pristine ZnO photoanode, with a photocurrent density of up to 1.20 mA cm−2 at 1.23 V (vs. RHE) bias. The calculated value of ABPE for the composite photoanode was 0.258%, compared with 0.123% for the bare ZnO NRAs. The co-decoration of NCN and CQDs enhanced the charge separation efficiency and expanded the spectral response range, contributing to the improved PEC properties of the composite photoanode. [ABSTRACT FROM AUTHOR]

Extrachromosomal circular DNAs (eccDNAs) have emerged as important intra-cellular mobile genetic elements that affect gene copy number and exert in trans regulatory roles within the cell nucleus. Here, we describe scCircle-seq, a method for profiling eccDNAs and unraveling their diversity and complexity in single cells. We implement and validate scCircle-seq in normal and cancer cell lines, demonstrating that most eccDNAs vary largely between cells and are stochastically inherited during cell division, although their genomic landscape is cell type-specific and can be used to accurately cluster cells of the same origin. eccDNAs are preferentially produced from chromatin regions enriched in H3K9me3 and H3K27me3 histone marks and are induced during replication stress conditions. Concomitant sequencing of eccDNAs and RNA from the same cell uncovers the absence of correlation between eccDNA copy number and gene expression levels, except for a few oncogenes, including MYC, contained within a large eccDNA in colorectal cancer cells. Lastly, we apply scCircle-seq to one prostate cancer and two breast cancer specimens, revealing cancer-specific eccDNA landscapes and a higher propensity of eccDNAs to form in amplified genomic regions. scCircle-seq is a scalable tool that can be used to dissect the complexity of eccDNAs across different cell and tissue types, and further expands the potential of eccDNAs for cancer diagnostics. Extrachromosomal circular DNAs (eccDNAs) affect gene expression and tumour progression. Here, the authors report a method, scCircle-seq, for eccDNA profiling in single cells, demonstrating the stochasticity, cell type specificity, and dynamics of eccDNAs in cell lines and primary tumour samples. [ABSTRACT FROM AUTHOR]

The aging processes of microplastics (MPs) are prevalent in natural environments. Understanding the aging mechanisms of MPs is crucial for assessing their environmental behavior and potential risks. In this study, we selected polylactic acid (PLA) and polyethylene (PE) as representatives of biodegradable and conventional plastics, respectively, to examine changes in their physicochemical properties induced by water and UV light exposure. Laboratory aging resulted in significant fragmentation, characterized by cracks and pores on the surfaces, for both types of MPs, with PLA MPs exhibiting more severe changes, particularly under combined UV and water exposure. Notably, PLA MPs tended to become progressively smaller after aging, whereas PE MPs did not show significant size changes. Chemical analyses of aged MPs using micro-Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed a substantial increase in the carbonyl index (CI) and oxygen content for PE, suggesting surface oxidation during photo-oxidation. Conversely, PLA MPs displayed a CI decrease, along with an oxygen content increase, indicating the breakdown of ester linkages in PLA and the formation of other oxidation products. Furthermore, we developed and optimized pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) methods to identify potential chemical degradation products of PE and PLA, considering their differing thermal stabilities. We observed a distinct trend regarding the peaks in the chromatogram of aged MPs and identified the typical oxidation and crosslinking products for PLA. Additionally, after the aging process, both PE and PLA exhibited a significant increase in organic carbon content, with the eluate containing submicron/nano-sized particles. This study provides a scientific foundation for a deeper understanding of the environmental aging mechanisms of various MPs, particularly in regards to the effects of UV irradiation and water exposure. [ABSTRACT FROM AUTHOR]

The utilization of two-dimensional (2D) nanosheets as catalysts is promising due to their atomic-scale thickness and extensive surfaces. The development of a high-quality, flexible Pt-based nanosheet with an efficient synthesis method is imperative. In this study, we present a 2D Pt2Pd porous alloy nanosheet synthesized through a novel process involving molten-alkali mechanochemical and borane morpholine complex reduction methods. This nanosheet exhibits a pristine 2D active surface, serving as an efficient catalyst for the oxygen reduction reaction (ORR). The Pt2Pd porous alloy nanosheet catalyst displays a high half-wave potential of 0.956 V versus the reversible hydrogen electrode (RHE), along with remarkable mass and specific activities of 1.38 A mg−1Pt and 3.70 mA cm−2 (at 0.9 V versus the RHE). When applied as the cathode in a zinc–air battery, it achieves a power density of 0.31 W cm−2 and demonstrates outstanding durability. This research introduces an innovative strategy for advancing high-quality, flexible 2D Pt-based materials. [ABSTRACT FROM AUTHOR]

Objective: With the increasing number of patients with cognitive impairment, nonpharmacological ways to delay cognitive impairment have attracted people's attention, such as lifestyle changes and nutritional supplementation. Folic acid supplementation appears to be a promising treatment option. However, it remains controversial whether folic acid supplementation is effective in delaying adult's cognitive impairment. Therefore, we conducted a meta‐analysis to analyze the effects of folic acid supplementation on different cognitive impairments. Methods: We systematically searched PubMed, Web of Science, EMbase, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure (CNKI), WanFang and VIP databases for randomized controlled trials on January 22, 2024. The included population comprised those diagnosed with cognitive impairment. We included trials that compared folic acid treatment with placebo, other dosing regimens, or other intervention controls. Conducting quality evaluation of included studies according to the Cochrane Risk of Bias tool. Statistical analyses were performed using Review Manager software. Results: Twenty‐two trials, including 3604 participants, met inclusion criteria. Compared with controls, the cognitive function of Alzheimer's disease (AD) patients showed improvement with folic acid supplementation: supplementation with < 3 mg (standardized mean differences (SMD) = 0.15, 95% confidence interval (CI) –0.10 to 0.41), and supplementing with ≥ 3 mg folic acid could improve cognitive function in AD patients (SMD = 1.03, 95% CI 0.18 to 1.88). Additionally, it reduced homocysteine (HCY) levels (mean differences (MD) = –4.74, 95% CI –8.08 to –1.39). In mild cognitive impairment (MCI) patients, cognitive function improved with folic acid supplementation: supplementation with > 400 μg (SMD = 0.38, 95% CI 0.13 to 0.63), and supplementation with ≤ 400 μg (SMD = 1.10, 95% CI 0.88 to 1.31). It also reduced HCY levels at intervention ≤ 6 months (MD = –3.93, 95% CI –5.05 to –2.82) and intervention > 6 months (MD = –4.38, 95% CI –5.15 to –3.61). However, supplementing with folic acid did not improve cognitive function in vascular cognitive impairment (VCI) patients, with folic acid supplements < 3 mg (SMD = –0.07, 95% CI –0.23 to –0.08), folic acid supplements ≥ 3 mg (SMD = 0.46, 95% CI –0.57 to 1.49), however, it reduced HCY levels at intervention > 6 months (MD = –5.91, 95% CI –7.13 to –4.69) and intervention ≤ 6 months (MD = –11.15, 95% CI –12.35 to –9.95). Conclusions: Supplement folic acid is beneficial to the cognitive profile of patients with MCI, supplementation with ≥ 3 mg folic acid can improve cognitive function in AD patients. [ABSTRACT FROM AUTHOR]

A quasi-continuous-wave (QCW) laser diode (LD) driver is commonly used to drive diode bars and stacks designed specifically for QCW operations in solid-state lasers. Such drivers are optimized to deliver peak current and voltage pulses to LDs while maintaining low average power levels. As a result, they are widely used in laser processing devices and laser instruments. Traditional high-energy QCW LD drivers primarily use capacitors as energy storage components and pulsed constant-current sources with op-amps and power metal-oxide-semiconductor field-effect transistors (MOSFETs) as their core circuits for generating repeated constant-current pulses. The drawback of this type of driver is that the driver's output voltage needs to be manually adjusted according to the operating voltage of the load before use to maximize driver efficiency while providing a sufficient current. Another drawback is its inability to automatically adjust the output voltage to maintain high efficiency when the load changes during the driver operation. Drastic changes in the load can cause the driver to fail to function properly in extreme cases. Based on the above traditional circuit structure, this study designed a stability compensation circuit and realized a QCW LD driver for driving a GS20 diode stack with a maximum repetition rate of 100 Hz, a constant current of approximately 300 A, a load voltage of approximately 10 V, and a pulse width of approximately 300 μ s. In particular, a high-efficiency, load-adaptive driving method was used with the MOSFETs in the critical saturation region (i.e., between the linear and saturated regions), controlling its power loss effectively while achieving maximum output current of the driver. The experiments demonstrated that the driver efficiency could be maintained at more than 80% when the load current varied from 50 to 300 A. [ABSTRACT FROM AUTHOR]

Background: Annexin (ANN) is calcium (Ca2+)-dependent and phospholipid binding protein family, which is involved in plant growth and development and response to various stresses. However, little known about ANN genes were identified from crape myrtle, an ornamental horticultural plant widely cultivated in the world. Results: Here, 9 LiANN genes were identified from Lagerstroemia indica, and their characterizations and functions were investigated in L. indica for the first time. The LiANN genes were divided into 2 subfamilies. The gene structure, chromosomal location, and collinearity relationship were also explored. In addition, the GO annotation analysis of these LiANNs indicated that they are enriched in molecular functions, cellular components, and biological processes. Moreover, transcription factors (TFs) prediction analysis revealed that bHLH, MYB, NAC, and other TFs can interact with the LiANN promoters. Interestingly, the LiANN2/4/6–9 were demonstrated to play critical roles in the branching architecture of crape myrtle. Furthermore, the LiANN2/6/8/9 were differentially expressed under salt treatment, and a series of TFs regulating LiANN2/6/8/9 expression were predicted to play essential roles in salt resistance. Conclusions: These results shed light on profile and function of the LiANN gene family, and lay a foundation for further studies of the LiANN genes. [ABSTRACT FROM AUTHOR]

Novel biologics in MG therapy research is on the rise. This research aimed to investigate the characteristics of registered trials on novel therapies for myasthenia gravis on ClinicalTrials.gov. This cross-sectional study used a descriptive approach to assess the features of the included trials on ClinicalTrials.gov. We found 62 registered trials from 2007 to 2023 on ClinicalTrials.gov. The results showed a yearly rise in the number of registered trials (r = 0.76, p < 0.001). Following 2017, more industry-sponsored trials were conducted (91.5% [43] vs. 60% [9], p = 0.009), fewer results were released (10.6% [5] vs. 60% [9], p = 0.001), and more trials entered phase 3 (67.4% [31] vs. 20% [2], p = 0.001). The most researched novel medications were neonatal Fc receptor inhibitors (51.2% [21]), complement inhibitors (39.0% [16]), and B cell depletors (14.6% [6]). According to the website's data, the neonatal Fc receptor inhibitors and complement inhibitors were effective in treating myasthenia gravis patients in three trials (NCT03315130, NCT03669588, and NCT00727194). This study provides valuable insights into the profile of registered trials on novel therapies for myasthenia gravis. More clinical studies are needed in the future to prove the value of its application. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "scCircle-seq unveils the diversity and complexity of extrachromosomal circular DNAs in single cells." The correction states that the funding line for Mohit Virdi, a PhD student supported by the EURÊKA Foundation, was omitted from the original article. The correction has been made to the article. The article is licensed under a Creative Commons Attribution 4.0 International License, allowing for use, sharing, adaptation, distribution, and reproduction as long as appropriate credit is given to the original author(s) and source. [Extracted from the article]

The occurrence of ovarian cancer (OC) is a major factor in women's mortality rates. Despite progress in medical treatments, like new drugs targeting homologous recombination deficiency, survival rates for OC patients are still not ideal. The tumor microenvironment (TME) includes cancer cells, fibroblasts linked to cancer (CAFs), immune-inflammatory cells, and the substances these cells secrete, along with non-cellular components in the extracellular matrix (ECM). First, the TME mainly plays a role in inhibiting tumor growth and protecting normal cell survival. As tumors progress, the TME gradually becomes a place to promote tumor cell progression. Immune cells in the TME have attracted much attention as targets for immunotherapy. Immune checkpoint inhibitor (ICI) therapy has the potential to regulate the TME, suppressing factors that facilitate tumor advancement, reactivating immune cells, managing tumor growth, and extending the survival of patients with advanced cancer. This review presents an outline of current studies on the distinct cellular elements within the OC TME, detailing their main functions and possible signaling pathways. Additionally, we examine immunotherapy rechallenge in OC, with a specific emphasis on the biological reasons behind resistance to ICIs., Competing Interests: The reviewer LZ declared a shared parent affiliation with the authors to the handling editor at the time of review. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Chen, Yang, Ma and Zhang.)