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1.
J Adv Res ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38960276

ABSTRACT

INTRODUCTION: Growing interest toward RNA modification in cancer has inspired the exploration of gene sets related to multiple RNA modifications. However, a comprehensive elucidation of the clinical value of various RNA modifications in breast cancer is still lacking. OBJECTIVES: This study aimed to provide a strategy based on RNA modification-related genes for predicting therapy response and survival outcomes in breast cancer patients. METHODS: Genes related to thirteen RNA modification patterns were integrated for establishing a nine-gene-containing signature-RMscore. Alterations of tumor immune microenvironment and therapy response featured by different RMscore levels were assessed by bulk transcriptome, single-cell transcriptome and genomics analyses. The biological function of key RMscore-related molecules was investigated by cellular experiments in vitro and in vivo, using flow cytometry, immunohistochemistry and immunofluorescence staining. RESULTS: This study has raised an effective therapy strategy for breast cancer patients after a well-rounded investigation of RNA modification-related genes. With a great performance of predicting patient prognosis, high levels of the RMscore proposed in this study represented suppressive immune microenvironment and therapy resistance, including adjuvant chemotherapy and PD-L1 blockade treatment. As the key contributor of the RMscore, inhibition of WDR4 impaired breast cancer progression significantly in vitro and in vivo, as well as participated in regulating cell cycle and mTORC1 signaling pathway via m7G modification. CONCLUSION: Briefly, this study has developed promising and effective tactics to achieve the prediction of survival probabilities and treatment response in breast cancer patients.

2.
Int J Biol Macromol ; 276(Pt 2): 133958, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39033899

ABSTRACT

Lactobacillus helveticus exhibits a remarkable proteolytic system. However, the etiology of these protein hydrolysis characteristics, whether caused by extracellular proteinases (EP) or cell envelope proteinases (CEP), has been puzzling researchers. In this study, third-generation Nanopore whole genome sequencing and proteomics analysis were used to unravel the root cause of the aforementioned confusion. The genome of L. helveticus Lh191404 was 2,117,643 bp in length, with 67 secreted proteins were found. Combined with proteomic analysis, it was found that the protein composition of extraction from CEP and EP were indeed the same substance. Bioinformatics analysis indicated that the CEP belonged to the PrtH1 Variant (PrtH1_V) genotype by phylogenetic analysis. The three-dimensional structures of various domains within the PrtH1_V-191404 had been characterized, providing a comprehensive understanding of its structural features. Results of proteinase activity showed that the optimal reaction temperature was 40 °C, with a pH of 6.50. These findings suggested that the origin of EP in L. helveticus Lh191404 may be due to CEP being released into the substrate after detaching from the cell wall. This research is of guiding significance for further understanding the operational mechanism of the protein hydrolysis system in lactic acid bacteria.

3.
J Hazard Mater ; 477: 135072, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-39042988

ABSTRACT

During the process of black shale weathering, multiple heavy metal elements are concentrated in the soil, causing pollution. This study selected soil and black shale bedrock samples from high geological background areas to investigate the control of heavy metal element pollution by bedrock using spatial analysis. The research results indicate that the heavy metal content in black shale bedrock is extremely high, ranging from 2.3 to 13.1 times the background values of rock heavy metal elements. The heavy metal content in the soil formed through weathering is positively correlated with the bedrock, ranging from 1.1 to 21.3 times the background values. The coefficient of variation of rock samples ranges from 1.09 to 7.18, indicating significant variability.The analysis reveals that the control ability of pure rock over heavy metal elements is mainly moderate and high, accounting for over 70 %, with d being the most affected metal element. Except for As, the other seven elements exhibit strong spatial autocorrelation, showing distinct regional distribution characteristics. The soil elements demonstrate high homogeneity, with heavy metal elements from black shale bedrock primarily released through weathering serving as the main source of these elements.

4.
Langmuir ; 40(29): 14900-14907, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-38982885

ABSTRACT

The transfer of chirality from molecules to synthesized nanomaterials has recently attracted significant attention. Although most studies have focused on graphene and plasmonic metal nanostructures, layered transition metal dichalcogenides (TMDs), particularly MoS2, have recently garnered considerable attention due to their semiconducting and electrocatalytic characteristics. Herein, we report a new approach for the synthesis of chiral molybdenum sulfide nanomaterials based on a bottom-up synthesis method in the presence of chiral cysteine enantiomers. In the synthesis process, molybdenum trioxide and sodium hydrosulfide serve as molybdenum and sulfur sources, respectively. In addition, ascorbic acid acts as a reducing agent, resulting in the formation of zero-dimensional MoS2 nanodots. Moreover, the addition of cysteine enantiomers to the growth solutions contributes to the chirality evolution of the MoS2 nanostructures. The chirality is attributed to the cysteine enantiomer-induced preferential folding of the MoS2 planes. The growth mechanism and chiral structure of the nanomaterials are confirmed through a series of characterization techniques. This work combines chirality with the bottom-up synthesis of MoS2 nanodots, thereby expanding the synthetic methods for chiral nanomaterials. This simple synthesis approach provides new insights for the construction of other chiral TMD nanomaterials with emerging structures and properties. More significantly, the as-formed MoS2 nanodots exhibited highly defect-rich structures and chiroptical performance, thereby inspiring a high potential for emerging optical and electronic applications.

5.
BMC Cancer ; 24(1): 673, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38825709

ABSTRACT

Hepatocellular carcinoma (HCC) genomic research has discovered actionable genetic changes that might guide treatment decisions and clinical trials. Nonetheless, due to a lack of large-scale multicenter clinical validation, these putative targets have not been converted into patient survival advantages. So, it's crucial to ascertain whether genetic analysis is clinically feasible, useful, and whether it can be advantageous for patients. We sequenced tumour tissue and blood samples (as normal controls) from 111 Chinese HCC patients at Qingdao University Hospital using the 508-gene panel and the 688-gene panel, respectively. Approximately 95% of patients had gene variations related to targeted treatment, with 50% having clinically actionable mutations that offered significant information for targeted therapy. Immune cell infiltration was enhanced in individuals with TP53 mutations but decreased in patients with CTNNB1 and KMT2D mutations. More notably, we discovered that SPEN, EPPK1, and BRCA2 mutations were related to decreased median overall survival, although MUC16 mutations were not. Furthermore, we found mutant MUC16 as an independent protective factor for the prognosis of HCC patients after curative hepatectomy. In conclusion, this study connects genetic abnormalities to clinical practice and potentially identifies individuals with poor prognoses who may benefit from targeted treatment or immunotherapy.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Mutation , Humans , Liver Neoplasms/genetics , Liver Neoplasms/therapy , Liver Neoplasms/mortality , Liver Neoplasms/pathology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/therapy , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/pathology , Male , Female , Prognosis , Middle Aged , Aged , Adult , Biomarkers, Tumor/genetics , Genomics/methods , BRCA2 Protein/genetics , Molecular Targeted Therapy , Hepatectomy , Gene Expression Profiling , Tumor Suppressor Protein p53/genetics , DNA-Binding Proteins , Neoplasm Proteins , beta Catenin
6.
Cell Mol Immunol ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38942796

ABSTRACT

Metabolic changes play a crucial role in determining the status and function of macrophages, but how lipid reprogramming in macrophages contributes to tumor progression is not yet fully understood. Here, we investigated the phenotype, contribution, and regulatory mechanisms of lipid droplet (LD)-laden macrophages (LLMs) in hepatocellular carcinoma (HCC). Enriched LLMs were found in tumor tissues and were associated with disease progression in HCC patients. The LLMs displayed immunosuppressive phenotypes (with extensive expression of TREM2, PD-L1, CD206, and CD163) and attenuated the antitumor activities of CD8+ T cells. Mechanistically, tumor-induced reshuffling of cellular lipids and TNFα-mediated uptake of tumoral fatty acids contribute to the generation of triglycerides and LDs in macrophages. LDs prolong LLM survival and promote CCL20 secretion, which further recruits CCR6+ Tregs to HCC tissue. Inhibiting LLM formation by targeting DGAT1 and DGAT2, which catalyze the synthesis of triglycerides, significantly reduced Treg recruitment, and delayed tumor growth in a mouse hepatic tumor model. Our results reveal the suppressive phenotypes and mechanisms of LLM enrichment in HCC and suggest the therapeutic potential of targeting LLMs for HCC patients.

7.
Anal Chem ; 96(24): 10074-10083, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38848224

ABSTRACT

Numerous high-performance nanotechnologies have been developed, but their practical applications are largely restricted by the nanomaterials' low stabilities and high operation complexity in aqueous substrates. Herein, we develop a simple and high-reliability hydrogel-based nanotechnology based on the in situ formation of Au nanoparticles in molybdenum disulfide (MoS2)-doped agarose (MoS2/AG) hydrogels for electrophoresis-integrated microplate protein recognition. After the incubation of MoS2/AG hydrogels in HAuCl4 solutions, MoS2 nanosheets spontaneously reduce Au ions, and the hydrogels are remarkably stained with the color of as-synthetic plasmonic Au hybrid nanomaterials (Au staining). Proteins can precisely mediate the morphologies and optical properties of Au/MoS2 heterostructures in the hydrogels. Consequently, Au staining-based protein recognition is exhibited, and hydrogels ensure the comparable stabilities and sensitivities of protein analysis. In comparison to the fluorescence imaging and dye staining, enhanced sensitivity and recognition performances of proteins are implemented by Au staining. In Au staining, exfoliated MoS2 semiconductors directly guide the oriented growth of plasmonic Au nanostructures in the presence of formaldehyde, showing environment-friendly features. The Au-stained hydrogels merge the synthesis and recognition applications of plasmonic Au nanomaterials. Significantly, the one-step incubation of the electrophoretic hydrogels leads to high simplicity of operation, largely challenging those multiple-step Ag staining routes which were performed with high complexity and formaldehyde toxicity. Due to its toxic-free, simple, and sensitive merits, the Au staining integrated with electrophoresis-based separation and microplate-based high-throughput measurements exhibits highly promising and improved practicality of those developing nanotechnologies and largely facilitates in-depth understanding of biological information.


Subject(s)
Disulfides , Gold , Hydrogels , Molybdenum , Molybdenum/chemistry , Disulfides/chemistry , Gold/chemistry , Hydrogels/chemistry , Metal Nanoparticles/chemistry , Electrophoresis , Proteins/analysis , Proteins/chemistry
8.
Dig Liver Dis ; 2024 May 08.
Article in English | MEDLINE | ID: mdl-38724344

ABSTRACT

OBJECTIVE: Laparoscopic hepatectomy (LH) has become a common surgery for the treatment of liver tumor. To evaluate the surgical quality of laparoscopic hepatectomy under the context of precision surgery with Textbook outcome (TO), a comprehensive and holistic assessment approach. METHODS: A total of 1056 patients who underwent laparoscopic hepatectomy from May 2016 and December 2022 were enrolled in the study. All the patients were performed hepatectomy. The rate of TO and factors associated with achieving TO were examined. RESULTS: Among the 1056 patients, 75 % patients achieved TO. The main reason limited patients achieving textbook outcomes was prolonged length of hospital stay (LOS). The univariate analysis indicated that age>65, ASA classification ≥3, liver cirrhosis, tumor size > 3 cm, tumor number ≥2, type of primary cancer, and IWATE DSS were significantly associated with non-achievement of TO. The multivariate analysis indicated that the ASA classification ≥3 and advanced difficulty level in IWATE DSS independent factors associated with achieving TO. Reaching TO can significantly prolong the postoperative recurrence time and overall survival time of hepatocellular carcinoma patients. CONCLUSION: In the context of precision surgery, 75 % patients undergoing laparoscopic hepatectomy achieved a TO. Patients who achieved TO had significantly improved survival.

9.
J Hazard Mater ; 472: 134496, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38718508

ABSTRACT

Effective capture of radioactive iodine from nuclear fuel reprocessing is of great importance for public safety as well as the secure utility of nuclear energy. In this work, a hydrophobic nanosheet silicalite-1 (NSL-1) zeolite with an adjustable size was developed for efficient iodine (I2) and methyl iodide (CH3I) adsorption. The optimized all-silica zeolite NSL-1 exhibits an excellent I2 uptake capacity of 553 mg/g within 45 min and a CH3I uptake capacity of 262 mg/g within 1 h. Benefiting from the reduced thickness and enhanced porosity, microporous NSL-1 possesses enhanced iodine adsorption capacity and fast adsorption kinetics, which is a considerable high value among inorganic materials. Unexpectedly, the remarkable characters of high hydrophobicity, acid-resistance and anti-oxidation endow it a higher iodine uptake capacity than traditional aluminosilicate zeolites. More importantly, the high uptake selectivity toward I2 possessed by NSL-1 owing to its hydrophobic skeleton under simulated dynamic conditions. The low cost, facile and scalable synthesis of NSL-1 further highlights great prospects for applications in the nuclear industry. This work provides useful insights for designing efficient adsorbents for iodine capture.

10.
Phys Med ; 122: 103385, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38810392

ABSTRACT

PURPOSE: The segmentation of abdominal organs in magnetic resonance imaging (MRI) plays a pivotal role in various therapeutic applications. Nevertheless, the application of deep-learning methods to abdominal organ segmentation encounters numerous challenges, especially in addressing blurred boundaries and regions characterized by low-contrast. METHODS: In this study, a multi-scale visual attention-guided network (VAG-Net) was proposed for abdominal multi-organ segmentation based on unpaired multi-sequence MRI. A new visual attention-guided (VAG) mechanism was designed to enhance the extraction of contextual information, particularly at the edge of organs. Furthermore, a new loss function inspired by knowledge distillation was introduced to minimize the semantic disparity between different MRI sequences. RESULTS: The proposed method was evaluated on the CHAOS 2019 Challenge dataset and compared with six state-of-the-art methods. The results demonstrated that our model outperformed these methods, achieving DSC values of 91.83 ± 0.24% and 94.09 ± 0.66% for abdominal multi-organ segmentation in T1-DUAL and T2-SPIR modality, respectively. CONCLUSION: The experimental results show that our proposed method has superior performance in abdominal multi-organ segmentation, especially in the case of small organs such as the kidneys.


Subject(s)
Abdomen , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Humans , Image Processing, Computer-Assisted/methods , Abdomen/diagnostic imaging , Deep Learning , Neural Networks, Computer
11.
Zhongguo Zhong Yao Za Zhi ; 49(3): 661-670, 2024 Feb.
Article in Chinese | MEDLINE | ID: mdl-38621870

ABSTRACT

Scorpions, a group of oldest animals with wide distribution in the world, have a long history of medicinal use. Scorpio, the dried body of Buthus martensii, is a rare animal medicine mainly used for the treatment of liver diseases, spasm, and convulsions in children in China. The venom has been considered as the active substance of scorpions. However, little is known about the small molecules in the venom of scorpions. According to the articles published in recent years, scorpions contain amino acids, fatty acids, steroids, and alkaloids, which endow scorpions with antimicrobial, anticoagulant, metabolism-regulating, and antitumor activities. This paper summarizes the small molecule chemical components and pharmacological activities of scorpions, with a view to providing valuable information for the discovery of new active molecules and the clinical use of scorpions.


Subject(s)
Animals, Poisonous , Anti-Infective Agents , Scorpion Venoms , Animals , Child , Humans , Peptides/chemistry , Scorpions/chemistry , Scorpions/metabolism , DNA, Complementary , Scorpion Venoms/pharmacology
12.
World J Gastrointest Surg ; 16(2): 307-317, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38463380

ABSTRACT

BACKGROUND: Gallstones are common lesions that often require surgical intervention. Laparoscopic cholecystectomy is the treatment of choice for symptomatic gallstones. Preoperatively, the anatomical morphology of the cystic duct (CD), needs to be accurately recognized, especially when anatomical variations occur in the CD, which is otherwise prone to bile duct injury. However, at present, there is no optimal classification system for CD morphology applicable in clinical practice, and the relationship between anatomical variations in CDs and gallstones remains to be explored. AIM: To create a more comprehensive clinically applicable classification of the morphology of CD and to explore the correlations between anatomic variants of CD and gallstones. METHODS: A total of 300 patients were retrospectively enrolled from October 2021 to January 2022. The patients were divided into two groups: The gallstone group and the nongallstone group. Relevant clinical data and anatomical data of the CD based on magnetic resonance cholangiopancreatography (MRCP) were collected and analyzed to propose a morphological classification system of the CD and to explore its relationship with gallstones. Multivariate analysis was performed using logistic regression analyses to identify the independent risk factors using variables that were significant in the univariate analysis. RESULTS: Of the 300 patients enrolled in this study, 200 (66.7%) had gallstones. The mean age was 48.10 ± 13.30 years, 142 (47.3%) were male, and 158 (52.7%) were female. A total of 55.7% of the patients had a body mass index (BMI) ≥ 24 kg/m2. Based on the MRCP, the CD anatomical typology is divided into four types: Type I: Linear, type II: n-shaped, type III: S-shaped, and type IV: W-shaped. Univariate analysis revealed differences between the gallstone and nongallstone groups in relation to sex, BMI, cholesterol, triglycerides, morphology of CD, site of CD insertion into the extrahepatic bile duct, length of CD, and angle between the common hepatic duct and CD. According to the multivariate analysis, female, BMI (≥ 24 kg/m2), and CD morphology [n-shaped: Odds ratio (OR) = 10.97, 95% confidence interval (95%CI): 5.22-23.07, P < 0.001; S-shaped: OR = 4.43, 95%CI: 1.64-11.95, P = 0.003; W-shaped: OR = 7.74, 95%CI: 1.88-31.78, P = 0.005] were significantly associated with gallstones. CONCLUSION: The present study details the morphological variation in the CD and confirms that CD tortuosity is an independent risk factor for gallstones.

13.
Patient Prefer Adherence ; 18: 657-666, 2024.
Article in English | MEDLINE | ID: mdl-38500561

ABSTRACT

Purpose: To test a hypothetical pathway model to estimate the links between health literacy, social support, illness perception, and disease management self-efficacy. Methods: This cross-sectional study, conducted from June to October 2022, involved the recruitment of 210 patients with chronic diseases at two primary care facilities. Participants completed the Health Literacy Management Scale, Self-Efficacy for Managing Chronic Disease 6-Item Scale, Social Support Rating Scale and Brief Illness Perception Questionnaire. We used the PROCESS macro for R to determine the hypothetical pathway model. Results: The direct effect of health literacy on self-efficacy was significant (ß=0.1792, 95% CI: 0.0940-0.2644), and social support played a partial mediating role between health literacy and self-efficacy (ES=0.0761, 95% CI: 0.0398-0.1204). Illness perception moderated the relationship between social support and self-efficacy (ß=-0.0153, 95% CI: -0.0268- -0.0039). Conclusion: Proposed a conceptual model including the mediating effect of social support and the moderating effect of illness perception, which helps to clarify the underlying mechanisms between health literacy and self-efficacy.

14.
Heliyon ; 10(3): e25443, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38327471

ABSTRACT

Background: We aimed to explore the potential risk factors and short-term prognosis for SIRS after thermal ablation of hepatocellular carcinoma (HCC). Methods: Data from patients with HCC who underwent thermal ablation in the Third Affiliated Hospital of Sun Yat-sen University between January 2015 and August 2021 were retrieved from the perioperative database. Pre-, intra- and postoperative data between SIRS group and non-SIRS group were compared and multivariate logistic regression analysis was performed to identify the risk factors for SIRS after thermal ablation. Results: A total of 1491 patients were enrolled and 234 (15.7 %) patients developed SIRS after thermal ablation. Compared with those without SIRS, patients with SIRS had a longer hospital stay, higher hospitalization costs and higher risk of more severe postoperative complications. In the multivariate logistic regression analysis, current smoking (OR 1.58, 95 %CI 1.09-2.29), decreased HCT (OR 1.51,95 %CI 1.11-2.04), NEUT < 1.5 × 109/L(OR 1.74, 95 %CI 1.14-2.65), NEUT% < 0.5 or > 0.7 (OR 1.36, 95 %CI 1.01-1.83) and PT > 16.3s (OR 2.42, 95 %CI 1.57-3.74) were significantly associated with postoperative SIRS. Conclusions: Current smoking, decreased HCT, neutropenia, abnormal percentage of neutrophils and prolonged PT are the independent risk factors for SIRS after thermal ablation of HCC, which worsens outcomes of patients. This study can help identify high-risk population and guide appropriate care so as to reduce the incidence of postoperative SIRS.

15.
J Hazard Mater ; 465: 133227, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38091800

ABSTRACT

Achieving efficient uranium adsorption from highly acidic wastewater is still considered challenging. Here, an inorganic-organic hybridized self-assembly material (rPFE-10) with redox activity was constructed by phytic acid (PA), ethylenediamine (EDA), and Fe(II) via a facile one-pot route, and further applied for U(VI) removal. In the static adsorption experiment, rPFE-10 achieved the maximum U(VI) adsorption capacity of 717.1 mg/g at the optimal pH of 3.5. It also performed preeminently in a highly acidic condition of pH = 1.0, with the highest adsorption capacity of 551.2 mg/g and an equilibrium time of 30 min. Moreover, rPFE-10 exhibited a pH-responsive adsorption selectivity for U(VI) and An-Ln (S(U(VI)) and S(An-Ln)), which increased to 69 % and 94 % respectively as pH decreased from 3.0 to 1.0. Additionally, the spectral analysis revealed a reconstruction mechanism induced by multiple synergistic adsorption, in which U(VI) exchange with EDA+/2+ and Fe2+/3+ and earned suitable coordination geometry and ligand environment to coordinate with PA (mainly P-OH), while partial U(VI) is reduced by Fe(II) in framework. This work not only highlights the facile strategy for enhanced U(VI) retention in highly acidic solution, but expands the potential application of supramolecular self-assembly material in treatment of nuclear wastewater.

16.
Cell Signal ; 114: 111015, 2024 02.
Article in English | MEDLINE | ID: mdl-38113977

ABSTRACT

The bone formation (osteogenesis) of human periodontal ligament cells (hPDLCs) under tension stress is essential for alveolar bone remodeling during orthodontic tooth movement (OTM). Deubiquitinating enzymes (DUBs) remove ubiquitin from target proteins, affecting their function and mediating cell survival and differentiation. However, whether and how DUBs regulate hPDLC function under tension force is poorly understood. In this study, we first investigated the expression of DUBs in hPDLCs under cyclic tension stimulation (CTS). Up-regulation of USP12 was observed in hPDLCs and at the tension side of molar teeth in OTM C57BL6 mice models. Knockdown (KD) of USP12 led to enhanced osteogenesis of hPDLCs under CTS. RNA-seq analysis suggested that the unfolded protein response (UPR) was the prevailing biological process in hPDLCs with USP12 KD, indicating that USP12 depletion triggered endoplasmic reticulum (ER) stress. The three major UPR-related signaling branches, namely PERK/eIF2α/ATF4, IRE1α/XBP1s, and ATF6 axis, were activated in hPDLCs with USP12 KD. By utilizing specific inhibitors, we proved that the PERK/eIF2α/ATF4 axis predominantly mediated the enhanced osteogenesis in hPDLCs with USP12 KD under CTS. In summary, our study demonstrates that USP12 serves as a key regulator for CTS-induced osteogenesis in hPDLCs, suggesting that USP12 upregulation serves as an adaptive mechanism for hPDLCs to alleviate ER stress during OTM.


Subject(s)
Osteogenesis , Periodontal Ligament , Humans , Animals , Mice , Osteogenesis/physiology , Endoribonucleases/metabolism , Mice, Inbred C57BL , Protein Serine-Threonine Kinases/metabolism , Cell Differentiation/physiology , Cells, Cultured , Ubiquitin Thiolesterase/metabolism
17.
J Environ Manage ; 351: 119850, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38141346

ABSTRACT

Alpine meadows constitute one of the major ecosystems on the Qinghai-Tibetan Plateau, with livestock grazing exerting a considerable impact on their biodiversity. However, the degree to which plant diversity influences community stability under different grazing intensities remains unclear in this region. This study conducted controlled grazing experiments across four levels of grazing intensity (no-, low-, medium-, and high-grazing) based on herbage utilization rate to assess the influence of grazing intensities on plant community structure and diversity-stability relationships. We discovered that high-grazing reduced plant diversity and attenuated the temporal stability and resistance of above-ground biomass. No- and low-grazing could alleviate plant biomass loss, with community resistance being optimal under low-grazing. The direct effects of livestock grazing on temporal stability were found to be negligible. Plant characteristics and diversity accounted for a substantial proportion of livestock grazing effects on community resistance (R2 = 0.46), as revealed by piecewise structural equation model analysis. The presence of plant diversity enhances the resistance of alpine meadows against disturbance and accelerates the recovery after grazing. Our results suggest that low-grazing intensity may represent a judicious option for preserving species diversity and community stability on the Qinghai-Tibetan Plateau.


Subject(s)
Ecosystem , Livestock , Animals , Grassland , Biodiversity , Biomass , Plants
18.
Anal Chem ; 95(51): 18859-18870, 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38096265

ABSTRACT

Trivalent Au ions are easily reduced to be zerovalent atoms by coexisting reductant reagents, resulting in the subsequent accumulation of Au atoms and formation of plasmonic nanostructures. In the absence of stabilizers or presence of weak stabilizers, aggregative growth of Au nanoparticles (NPs) always occurs, and unregular multidimensional Au materials are consequently constructed. Herein, the addition of nanomole-level mercury ions can efficiently prevent the epitaxial accumulation of Au atoms, and separated Au NPs with mediated morphologies and superior plasmonic characteristics are obtained. Experimental results and theoretical simulation demonstrate the Hg-concentration-reliant formation of plasmonic nanostructures with their mediated sizes and shapes in the presence of weak reductants. Moreover, the sensitive plasmonic responses of reaction systems exhibit selectivity comparable to that of Hg species. As a concept of proof, polymeric carbon dots (CDs) were used as the initial reductant, and the reactions between trivalent Au and CDs were studies. Significantly, Hg atoms prevent the epitaxial accumulation of Au atoms, and plasmonic NPs with decreased sizes were in situ synthesized, corresponding to varied surface plasmonic resonance absorption performance of the CD-induced hybrids. Moreover, with the integration of sensing substrates of CD-doped hydrogels, superior response stabilities, analysis selectivity, and sensitivity of Hg2+ ions were achieved on the basis of the mercury-mediated in situ chemical reactions between trivalent Au ions and reductant CDs. Consequently, a high-performance sensing strategy with the use of Au NP-staining hydrogels (nanostaining hydrogels) was exhibited. In addition to Hg sensing, the nanostaining hydrogels facilitated by doping of emerging materials and advanced chem/biostrategies can be developed as high-performance on-site monitoring routes to various pollutant species.

19.
Environ Sci Technol ; 57(48): 19860-19870, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37976424

ABSTRACT

Electricity consumption and sludge yield (SY) are important indirect greenhouse gas (GHG) emission sources in wastewater treatment plants (WWTPs). Predicting these byproducts is crucial for tailoring technology-related policy decisions. However, it challenges balancing mass balance models and mechanistic models that respectively have limited intervariable nexus representation and excessive requirements on operational parameters. Herein, we propose integrating two machine learning models, namely, gradient boosting tree (GBT) and deep learning (DL), to precisely pointwise model electricity consumption intensity (ECI) and SY for WWTPs in China. Results indicate that GBT and DL are capable of mining massive data to compensate for the lack of available parameters, providing a comprehensive modeling focusing on operation conditions and designed parameters, respectively. The proposed model reveals that lower ECI and SY were associated with higher treated wastewater volumes, more lenient effluent standards, and newer equipment. Moreover, ECI and SY showed different patterns when influent biochemical oxygen demand is above or below 100 mg/L in the anaerobic-anoxic-oxic process. Therefore, managing ECI and SY requires quantifying the coupling relationships between biochemical reactions instead of isolating each variable. Furthermore, the proposed models demonstrate potential economic-related inequalities resulting from synergizing water pollution and GHG emissions management.


Subject(s)
Greenhouse Gases , Water Purification , Waste Disposal, Fluid , Wastewater , Sewage , Water Purification/methods , Greenhouse Effect
20.
Environ Sci Pollut Res Int ; 30(53): 114535-114555, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37861835

ABSTRACT

The scientific layout design of the groundwater pollution monitoring network (GPMN) can provide high quality groundwater monitoring data, which is essential for the timely detection and remediation of groundwater pollution. The simulation optimization approach was effective in obtaining the optimal design of the GPMN. The ant colony optimization (ACO) algorithm is an effective method for solving optimization models. However, the parameters used in the conventional ACO algorithm are empirically adopted with fixed values, which may affect the global searchability and convergence speed. Therefore, a parameter-iterative updating strategy-based ant colony optimization (PIUSACO) algorithm was proposed to solve this problem. For the GPMN optimal design problem, a simulation-optimization framework using PIUSACO algorithm was applied in a municipal waste landfill in BaiCheng city in China. Moreover, to reduce the computational load of the design process while considering the uncertainty of aquifer parameters and pollution sources, a genetic algorithm-support vector regression (GA-SVR) method was proposed to develop the surrogate model for the numerical model. The results showed that the layout scheme obtained using the PIUSACO algorithm had a significantly higher detection rate than ACO algorithm and random layout schemes, indicating that the designed layout scheme based on the PIUSACO algorithm can detect the groundwater pollution occurrence timely. The comparison of the iteration processes of the PIUSACO and conventional ACO algorithms shows that the global searching ability is improved and the convergence speed is accelerated significantly using the iteration updating strategy of crucial parameters. This study demonstrates the feasibility of the PIUSACO algorithm for the optimal layout design of the GPMN for the timely detection of groundwater pollution.


Subject(s)
Groundwater , Algorithms , Computer Simulation , Environmental Pollution , China
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