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Analyzing suspended particulate matter (SPM) in rivers has become crucial to assessing heavy metals in the fluvial system due to SPM's outstanding transportability. The Tibetan Plateau (TP), especially the Yarlung Tsangpo River (YTR) area, is under the potential threat of heavy metal pollution. Ten selected heavy metal elements (V, Cr, Co, Ni, Cu, Zn, As, Cd, Sb and Cs) were assessed in 27 SPM samples collected from the YTR main channel and its tributaries in June and September 2017 for the enrichment, temporal-spatial variation and potential source analysis of heavy metals in the YTR. The seasonal mean concentrations of the detected heavy metal followed the trend: Zn (290) > Cu (171) > As (144) > V (121) > Cr (91.5) > Ni (85.3) > Cs (74.3) > Co (28.1) > Sb (4.39) > Cd (0.57). The enrichment factor (EF) values suggested Cu (6.54), As (5.68), and Cd (4.45) as the most enriched heavy metal elements in the YTR, referring to moderate to severe enrichment, while other heavy metals were condonable. Temporally, heavy metals were more enriched in the SPM samples collected in September than in June because of the discrepancy in hydrodynamic conditions. Spatially, hot-spring-related elements showed a declining tendency downstream of the YTR. In the middle of the YTR, those heavy metals sensitive to anthropogenic activities would significantly concentrate in the SPM because it is the most populated and developed area in Tibet. Additionally, tributaries would accumulate more heavy metals than the YTR mainstream. Principal component analysis (PCA) extracted five components for heavy metals in the SPM. It revealed that hot springs and multivariate human activities would be the dominant contributors to the concentrated heavy metals in the SPM of the YTR.

Abstract Retinal ischemia‒reperfusion (I/R) injury can cause significant damage to human retinal neurons, greatly compromising their functions. Existing interventions have been proven to have little effect. Ferroptosis is a newly discovered type of programmed cell death that has been found to be involved in the process of ischemia‒reperfusion in multiple organs throughout the body. Studies have shown that it is also present in retinal ischemia‒reperfusion injury. A rat model of retinal ischemia‒reperfusion injury was constructed and treated with deferoxamine. In this study, we found the accumulation of Fe2+, reactive oxygen species (ROS), malondialdehyde (MDA), and the consumption of glutathione (GSH) via ELISA testing; increased expression of transferrin; and decreased expression of ferritin, SLC7A11, and GPX4 via Western blotting (WB) and real-time PCR testing. Structural signs of ferroptosis (mitochondrial shrinkage) were observed across multiple cell types, including retinal ganglion cells (RGCs), photoreceptor cells, and pigment epithelial cells. Changes in visual function were detected by F-VEP and ERG. The results showed that iron and oxidative stress were increased in the retinal ischemia‒reperfusion injury model, resulting in ferroptosis and tissue damage. Deferoxamine protects the structural and functional soundness of the retina by inhibiting ferroptosis through the simultaneous inhibition of hemochromatosis, the initiation of transferrin, and the degradation of ferritin and activating the antioxidant capacity of the System Xc-GSH-GPX4 pathway.

A reliable and efficient rail track defect detection system is essential for maintaining rail track integrity and avoiding safety hazards and financial losses. Eddy current (EC) testing is a non-destructive technique that can be employed for this purpose. The trade-off between spatial resolution and lift-off should be carefully considered in practical applications to distinguish closely spaced cracks such as those caused by rolling contact fatigue (RCF). A multi-channel eddy current sensor array has been developed to detect defects on rails. Based on the sensor scanning data, defect reconstruction along the rails is achieved using an inverse algorithm that includes both direct and iterative approaches. In experimental evaluations, the EC system with the developed sensor is used to measure defects on a standard test piece of rail with a probe lift-off of 4–6 mm. The reconstruction results clearly reveal cracks at various depths and spacings on the test piece.

Abstract Due to the destructive effects of marine heatwaves (MHWs) on marine ecosystems and local economies, whether they become more frequent and stronger under global warming has attracted much attention. The proposed event‐based algorithm identifies 3,843 MHWs during 1982–2020. Except for the MHW frequency, the global averaged duration, intensity, area and moving distance increased significantly. The contributions of the frequency and mean projection area to the total projection area were further investigated from the four categories of MHWs. The results showed that for moderate MHWs, frequency contributes more than the mean projection area to the increase in projection area; however, for strong, severe, and extreme MHWs, the mean projection area contributes much more than frequency. Due to the increased moving distance, the projected area change of the extreme MHW dominates the increase in the total projected area. The high sensitivity of extreme MHWs to global warming deserves extra attention.

Radioresistance is the major factor of glioblastoma multiforme (GBM) treatment failure and relapse. Hypoxia and autophagy are linked to radioresistance and poor prognosis in solid tumors, but mechanisms remain unknown. Thus, we hypothesize that hypoxia may activate autophagy through two critical factors, HIF1A and Beclin-1, resulting in radioresistance of GBM in vitro and in vivo. In this study, we first demonstrated that HIF1A was overexpressed in GBM tissues and predicted a poor prognosis via bioinformatics. Secondly, we determined that hypoxia induced high expression of HIF1A and upregulated levels of Beclin-1 and autophagy, while HIF1A knockdown by shRNA reduced the expression of Beclin-1. Then we revealed the crosstalk and mechanisms of HIF1A-associated-Beclin-1 in three aspects: (a) transcriptional regulation, (b) protein interaction, and (c) HIF1A/BNIP3/Beclin-1 signaling pathway. Furthermore, we confirmed that silencing HIF1A enhanced the radiosensitivity of GBM in vitro and in vivo. Additionally, Beclin-1 suppression by 3-MA could reverse radioresistance induced by HIF1A under hypoxia. In conclusion, we demonstrated that hypoxia triggered autophagy via HIF1A-associated Beclin-1, resulting in radioresistance in GBM. HIF1A knockdown improved GBM radiosensitivity, and silencing Beclin-1 could reverse HIF1A-induced radioresistance under hypoxic conditions. These findings may help us comprehend the molecular underpinnings of hypoxia-induced autophagy and provide a novel perspective and prospective treatment for GBM radiosensitization.

Adhesion to the intestinal tract provides the foundation for Lactobacillus to exert its benefits. Vacuum freeze-drying (VFD) is currently one of the main processing methods for Lactobacillus products. Therefore, the effects of VFD on the adhesion and survival of Lactiplantibacillus plantarum 67 were investigated in this study. The results show that L. plantarum 67 exhibits remarkable tolerance following successive exposure to simulated saliva, gastric juice and intestinal juice, and also has a strong adhesion ability to Caco-2 cells. The adhesion and survival rates of L. plantarum 67 significantly decreased after VFD in phosphate-buffered saline (PBS), whereas they significantly increased in protective agents (PAs) (p L. plantarum 67 aggregated more to Caco-2 cells in PAs than in PBS, and its shape and size were protected. Proteomics detection findings indicated that differentially expressed proteins (DEPs) related to adhesins and vitality and their pathways in L. plantarum 67 were significantly affected by VFD (p < 0.05). However, the expression of DEPs (such as cold shock protein, cell surface protein, adherence protein, chitin-binding domain and extracellular transglycosylase, membrane-bound protein) was improved by PAs. Compared with PBS, the PAs significantly adjusted the phosphotransferase system and amino sugar and nucleotide sugar metabolism pathways (p < 0.05). VFD decreased the adhesion and vitality of L. plantarum 67, while the PAs could exert protective effects by regulating proteins and pathways related to adhesion and vitality.

Background: The COVID-19 pandemic is a significant worldwide health crisis. Breast cancer patients with COVID-19 are fragile and require particular clinical care. This study aimed to identify the clinical characteristics of breast cancer patients with COVID-19 and the risks associated with anti-cancer treatment. Methods: The medical records of breast cancer patients with laboratory-confirmed COVID-19 were collected among 9559 COVID-19 patients from seven designated hospitals from 13th January to 18th March 2020 in Hubei, China. Univariate and multivariate analyses were performed to assess risk factors for COVID-19 severity. Results: Of the 45 breast cancer patients with COVID-19, 33 (73.3%) developed non-severe COVID-19, while 12 (26.7%) developed severe COVID-19, of which 3 (6.7%) patients died. The median age was 62 years, and 3 (6.7%) patients had stage IV breast cancer. Univariate analysis showed that age over 75 and the Eastern Cooperative Oncology Group (ECOG) score were associated with COVID-19 disease severity (P

ABSTRACT Rapid identification and continuous surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are critical for guiding the response to the COVID-19 pandemic. Whole-genome sequencing (WGS) is a preferred tool for this aim, but many laboratories suffer from a lack of resources to support population-level sequencing. Here, we describe two PCR strategies targeting spike protein mutations to identify the Alpha, Delta, and Omicron variants. Signature mutations were selected using a dedicated bioinformatic program. The selected mutations in Alpha and Delta variants were detected using multicolor melting curve analysis (MMCA). Thirty-two mutations of the Omicron variant were targeted using the MeltArray approach in one reaction, which was able to detect the Omicron subvariants BA.1, BA.2, BA.3, and BA.4/5. The limits of detection varied from five to 50 copies of RNA templates/reactions. No cross-reactivity was observed with nine other respiratory viruses, including other coronaviruses. We validated the MMCA and MeltArray assays using 309 SARS-CoV-2 positive samples collected at different time points. These assays exhibited 98.3% to 100% sensitivity and 100% specificity compared with WGS. Multiplexed real-time PCR strategies represent an alternative tool capable of identifying current SARS-CoV-2 VOCs, adaptable for emerging variants and accessible for laboratories using existing equipment and personnel. IMPORTANCE Rapid detection and mutation surveillance of SARS-CoV-2 VOCs is crucial for COVID-19 control, management, and prevention. We developed two rapid molecular assays based on the real-time PCR platform to identify important variants of concern, including the Omicron variant with a large number of mutations. Signature mutations were selected by an R program. Then, MMCA assays were established for Alpha and Delta variants, and a MeltArray assay targeting 32 mutations was developed for Omicron variant. These multiplexed PCR assays could be performed in a 96-well real-time PCR instrument within 2.5 h, offering a high-throughput choice for dynamic monitoring of SARS-CoV-2 VOCs in a standard microbiology laboratory.

Extracting classical information from quantum systems is an essential step of many quantum algorithms. However, this information could be corrupted as the systems are prone to quantum noises, and its distortion under quantum dynamics has not been adequately investigated. In this work, we introduce a systematic framework to study how well we can retrieve information from noisy quantum states. Given a noisy quantum channel, we fully characterize the range of recoverable classical information. This condition allows a natural measure quantifying the information recoverability of a channel. Moreover, we resolve the minimum information retrieving cost, which, along with the corresponding optimal protocol, is efficiently computable by semidefinite programming. As applications, we establish the limits on the information retrieving cost for practical quantum noises and employ the corresponding protocols to mitigate errors in ground state energy estimation. Our work gives the first full characterization of information recoverability of noisy quantum states from the recoverable range to the recovering cost, revealing the ultimate limit of probabilistic error cancellation.

Image reconstruction for electrical resistance tomography (ERT) is an ill-posed inverse problem. L1 regularization is used to solve the inverse problem. An effective method of Barzilai-Borwein gradient projection for sparse reconstruction (GPSR-BB) can resolve the inverse problem into bound-constrained quadratic programming and achieve a gradient projection with line search. However, it is computationally expensive to solve the problem when the data dimension is substantial. Hence, a projection method is employed and combined with the GPSR-BB algorithm to improve the real-time performance. The problem can be mainly solved in the Krylov subspace. For comparison, another L1 regularization GPSR-BB method based on the truncated singular value decomposition is also conducted. Both simulation (with 3D modeling) and experimental results demonstrate the new method’s effectiveness in reducing the computational time and improving the image quality.

Misgurnus anguillicaudatus (loach) is a widely distributed benthic fish in Asia. In this study, the alkaline protease was used to hydrolyze loach, and the hydrolysate products of different molecular weights were obtained by membrane separation. In vitro antioxidant assays showed that the

Eddy current (EC) testing has become one of the most common techniques for measuring metallic planar structures in various industrial scenarios such as infrastructures, automotive, manufacturing, and chemical engineering. There has been significant progress in measuring the geometry, electromagnetic properties, and defects of metallic planar structures based on electromagnetic principles. In this review, we summarize recent developments in EC computational models, systems, algorithms, and measurement approaches for planar structures. First, the computational models including analytical models, numerical methods, and plate property estimation algorithms are introduced. Subsequently, the impedance measurement system and probes are presented. In plate measurements, sensor signals are sensitive to probe lift-off, and various algorithms for reducing the lift-off effect are reviewed. These approaches can be used for measureing thickness and electromagnetic properties. Furthermore, defect detection for metallic plates is also discussed.

In the electrical capacitance tomography (ECT) systems, the electrodes, and cables may fail to function properly, which will cause several measurements missing. In these cases, image reconstruction can only use the remaining effective measurements. In order to make the reconstructed images close to the image results of the complete measurement set, it is necessary to use the incomplete measurements reasonably. The measurement/data recovery method and image reconstruction can be conducted to obtain the results, which meet the imaging needs under these circumstances. The measurement/data recovery method by using the sensitivity matrix and the regression model of least square support vector machine (LS-SVM) are proposed. The image recovery result is reconstructed by the method of total variation (TV) minimization. The simulations and experiments of gas-solids two-phase measurement are conducted to validate the method.

Abstract Progression to severe disease is a difficult problem in treating coronavirus disease 2019 (COVID‐19). The purpose of this study is to explore changes in markers of severe disease in COVID‐19 patients. Sixty‐nine severe COVID‐19 patients were included. Patients with severe disease showed significant lymphocytopenia. Elevated level of lactate dehydrogenase (LDH), C‐reactive protein (CRP), ferritin, and D‐dimer was found in most severe cases. Baseline interleukin‐6 (IL‐6) was found to be associated with COVID‐19 severity. Indeed, the significant increase of baseline IL‐6 was positively correlated with the maximal body temperature during hospitalization and with the increased baseline of CRP, LDH, ferritin, and D‐dimer. High baseline IL‐6 was also associated with more progressed chest computed tomography (CT) findings. Significant decrease in IL‐6 and improved CT assessment was found in patients during recovery, while IL‐6 was further increased in exacerbated patients. Collectively, our results suggest that the dynamic change in IL‐6 can be used as a marker for disease monitoring in patients with severe COVID‐19.

In this article, the modification effects on Al–Mg2Si before and after heat treatment were investigated with Ca, Sb, and (Ca + Sb). In comparison with single Ca or Sb, the samples with composition modifiers (Ca + Sb) had the optimal microstructure. The sample with a molar ratio for Ca-to-Sb of 1:1 obtained relatively higher properties, for which the Brinell hardness values before and after heat treatment were remarkably increased by 31.74% and 28.93% in comparison with bare alloy. According to differential scanning calorimetry analysis (DSC), it was found that the nucleation behavior of the primary Mg2Si phase could be significantly improved by using chemical modifiers. Some white particles were found to be embedded in the center of Mg2Si phases, which were deduced to be Ca5Sb3 through X-ray diffraction (XRD) and field-emission scanning electron microscope (FESEM) analyses. Furthermore, Ca5Sb3 articles possess a rather low mismatch degree with Mg2Si particles based on Phase Transformation Crystallography Lab software (PTCLab) calculation, meaning that the efficient nucleation capability of Ca5Sb3 for Mg2Si particles could be estimated.

On account of the exponential development of control theory and artificial intelligence technology in recent years, more and more control theory is applied to the control of robots, but PID control method due to the simple structure and good stability still has research value, the core and the difficulty is the optimization of PID parameters. In order to solve the underwater remotely operated vehicle (ROV) with high nonlinearity and strong coupling characteristics, it can adjust its attitude in time to ensure its control performance in the face of the disturbance of the external complex environment. By improving the particle swarm inertia weights, the particle swarm optimization (PSO) algorithm reduces the situation of falling into the local optimal solution and applies it to the PID adaptive parameterization. Comparing the improved PSO-PID with the traditional PID simulation, it is concluded that the improved PSO-PID control has certain improvement on the control performance of the ROV, which has certain feasibility. [ABSTRACT FROM AUTHOR]

Bile acids (BAs) are synthesized by the host liver from cholesterol and are delivered to the intestine, where they undergo further metabolism by gut microbes and circulate between the liver and intestines through various transporters. They serve to emulsify dietary lipids and act as signaling molecules, regulating the host's metabolism and immune homeostasis through specific receptors. Therefore, disruptions in BA metabolism, transport, and signaling are closely associated with cholestasis, metabolic disorders, autoimmune diseases, and others. Botanical triterpenoids and steroids share structural similarities with BAs, and they have been found to modulate BA metabolism, transport, and signaling, potentially exerting pharmacological or toxicological effects. Here, we have updated the research progress on BA, with a particular emphasis on new-found microbial BAs. Additionally, the latest advancements in targeting BA metabolism and signaling for disease treatment are highlighted. Subsequently, the roles of botanical triterpenoids in BA metabolism, transport, and signaling are examined, analyzing their potential pharmacological, toxicological, or drug interaction effects through these mechanisms. Finally, a research paradigm is proposed that utilizes the gut microbiota as a link to interpret the role of these important natural products in BA signaling.

Abstract Acute myocardial infarction (AMI) has become a public health disease threatening public life safety due to its high mortality. The lateral-flow assay (LFA) of a typical cardiac biomarker, troponin I (cTnI), is essential for the timely warnings of AMI. However, it is a challenge to achieve an ultra-fast and highly-sensitive assay for cTnI (hs-cTnI) using current LFA, due to the limited performance of chromatographic membranes. Here, we propose a barbed arrow-like structure membrane (BAS Mem), which enables the unidirectional, fast flow and low-residual of liquid. The liquid is rectified through the forces generated by the sidewalls of the barbed arrow-like grooves. The rectification coefficient of liquid flow on BAS Mem is 14.5 (highest to date). Using BAS Mem to replace the conventional chromatographic membrane, we prepare batches of lateral-flow strips and achieve LFA of cTnI within 240 s, with a limit of detection of 1.97 ng mL−1. The lateral-flow strips exhibit a specificity of 100%, a sensitivity of 93.3% in detecting 25 samples of suspected AMI patients. The lateral-flow strips show great performance in providing reliable results for clinical diagnosis, with the potential to provide early warnings for AMI.