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1.
Adv Mater ; : e2404576, 2024 May 02.
Article En | MEDLINE | ID: mdl-38696266

Although evidence indicates that the abnormal accumulation of α-synuclein (α-syn) in dopamine neurons of the substantia nigra is the main pathological feature of Parkinson's disease (PD), no compounds that have both α-syn antiaggregation and α-syn degradation functions have been successful in treating the disease in the clinic. Here, it is shown that black phosphorus nanosheets (BPNSs) interact directly with α-syn fibrils to trigger their disaggregation for PD treatment. Moreover, BPNSs have a specific affinity for α-syn through van der Waals forces. And BPNSs are found to activate autophagy to maintain α-syn homeostasis, improve mitochondrial dysfunction, reduce reactive oxygen species levels, and rescue neuronal death and synaptic loss in PC12 cells. It is also observed that BPNSs penetrate the blood-brain barrier and protect against dopamine neuron loss, alleviating behavioral disorders in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced mouse model and hA53T α-syn transgenic mice. Together, the study reveals that BPNSs have the potential as a novel integrated nanomedicine for clinical diagnosis and treatment of neurological diseases.

2.
RSC Adv ; 14(21): 14934-14941, 2024 May 02.
Article En | MEDLINE | ID: mdl-38716098

Ferroptosis, characterized by elevated iron levels and lipid peroxidation (LPO), is a recently identified regulatory mechanism of cell death. Its substantial involvement in ischemic tissue injury, neurodegenerative disorders, and cancer positions ferroptosis inhibition as a promising strategy for managing these diverse diseases. In this study, we introduce curcumin-polydopamine nanoparticles (Cur-PDA NPs) as an innovative ferroptosis inhibitor. Cur-PDA NPs demonstrate remarkable efficacy in chelating both Fe2+ and Fe3+in vitro along with scavenging free radicals. Cur-PDA NPs were found to efficiently mitigate reactive oxygen species, reduce Fe2+ accumulation, suppress LPO, and rejuvenate mitochondrial function in PC12 cells. Thus, these NPs can act as potent therapeutic agents against ferroptosis, primarily via iron chelation and reduction of oxidative stress.

4.
Aging (Albany NY) ; 16(8): 7249-7266, 2024 Apr 19.
Article En | MEDLINE | ID: mdl-38643469

OBJECTIVE: Prostate cancer (PCa) is the second disease threatening men's health, and anti-androgen therapy (AAT) is a primary approach for treating this condition. Increasing evidence suggests that long non-coding RNAs (lncRNAs) play crucial roles in the development of PCa and the process of AAT resistance. The objective of this study is to utilize bioinformatics methods to excavate lncRNAs association with AAT resistance and investigate their biological functions. METHODS: AAT resistance-related risk score model (ARR-RSM) was established by multivariate Cox analysis. Paired clinical tissue samples of 36 PCa patients and 42 blood samples from patients with PSA over 4 ng/ml were collected to verify the ARR-RSM. In vitro, RT-qPCR, CCK-8 and clone formation assays were displayed to verify the expression and function of AL354989.1 and AC007405.2. RESULTS: Pearson correlation analysis identified 996 lncRNAs were associated with AAT resistance (ARR-LncRs). ARR-RSM was established using multivariate Cox regression analysis, and PCa patients were divided into high-risk and low-risk groups. High-risk patients showed increased expression of AL354989.1 and AC007405.2 had poorer prognoses. The high-risk score correlated with advanced T-stage and N-stage. The AUC of ARR-RSM outperformed tPSA in diagnosing PCa. Silencing of AC007405.2 and AL354989.1 inhibited PCa cells proliferation and AAT resistance. CONCLUSIONS: In this study, we have discovered the clinical significance of AC007405.2 and AL354989.1 in predicting the prognosis and diagnosing PCa patients. Furthermore, we have confirmed their correlation with various clinical features. These findings provide potential targets for PCa treatment and a novel diagnostic and predictive indicator for precise PCa diagnosis.


Biomarkers, Tumor , Drug Resistance, Neoplasm , Prostatic Neoplasms , RNA, Long Noncoding , Humans , Male , Prostatic Neoplasms/genetics , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Prognosis , Drug Resistance, Neoplasm/genetics , Androgen Antagonists/therapeutic use , Androgen Antagonists/pharmacology , Cell Line, Tumor , Aged , Middle Aged , Gene Expression Regulation, Neoplastic , Cell Proliferation/genetics , Cell Proliferation/drug effects
5.
Sci Total Environ ; 931: 172764, 2024 Jun 25.
Article En | MEDLINE | ID: mdl-38670379

Terpenoids play a crucial role in atmospheric chemistry, contributing significantly to the formation of ozone and secondary organic aerosol. However, the accurate quantification of terpenoid emissions from biomass burning is currently lacking, leading to underestimated air quality impacts. This study developed a near real-time hourly open biomass burning (OBB) emission inventory named OBEIC, which incorporated geostationary and polar-orbiting satellite fire radiative power. The OBEIC inventory provided emission estimates of 69 terpenoids, categorized into four groups, at an hourly resolution. Monoterpenes were the dominant contributors to the total emissions, accounting for 58 % of the total terpenoid emissions from OBB. Notably, only 24 % of the total monoterpenes emitted from OBB were accounted for by α-pinene and ß-pinene, indicating the importance of quantifying emissions of other monoterpene species such as limonene and camphene. Additionally, oxygenated terpenoids, which were previously overlooked, contribute to 20 % of total terpenoid emissions from OBB. Diurnally, the emissions of terpenoids were primarily concentrated during the daytime (61 %); however, this study revealed the significance of nighttime emissions (39 %) as well. When compared to the biogenic and anthropogenic emissions, OBB made substantial contributions to nighttime isoprene (99.8 %), monoterpene (66.8 %), and sesquiterpene (61.7 %) emissions where OBB occurs (in 3 km range), suggesting its significant role in nighttime secondary pollutant formation. The methodology developed in this study has the potential to reduce uncertainties in OBB emissions estimation.

6.
Org Lett ; 26(16): 3441-3446, 2024 Apr 26.
Article En | MEDLINE | ID: mdl-38625098

Herein, a cooperative N-heterocyclic carbene- and palladium-catalyzed three-component reaction of alkynes with aldehydes and fluoroalkyl iodides is developed. A series of biologically valuable CF2R-incorporated α-substituted enones was obtained in moderate to good yields. This mild catalytic method exhibits exclusive regio- and stereoselectivity, excellent functional group tolerance, and a broad substrate scope including terminal and internal alkynes. Mechanistic investigations disclose that this alkyne fluoroalkylacylation proceeds via a radical relay process in which vinyl iodides serve as putative reaction intermediates.

7.
Comput Biol Med ; 174: 108409, 2024 May.
Article En | MEDLINE | ID: mdl-38593642

Lymphoma, the most prevalent hematologic tumor originating from the lymphatic hematopoietic system, can be accurately diagnosed using high-resolution ultrasound. Microscopic ultrasound performance enables clinicians to identify suspected tumors and subsequently obtain a definitive pathological diagnosis through puncture biopsy. However, the complex and diverse ultrasonographic manifestations of lymphoma pose challenges for accurate characterization by sonographers. To address these issues, this study proposes a Transformer-based model for generating descriptive ultrasound images of lymphoma, aiming to provide auxiliary guidance for ultrasound doctors during screening procedures. Specifically, deep stable learning is integrated into the model to eliminate feature dependencies by training sample weights. Additionally, a memory module is incorporated into the model decoder to enhance semantic information modeling in descriptions and utilize learned semantic tree branch structures for more detailed image depiction. Experimental results on an ultrasonic diagnosis dataset from Shanghai Ruijin Hospital demonstrate that our proposed model outperforms relevant methods in terms of prediction performance.


Lymphoma , Ultrasonography , Humans , Lymphoma/diagnostic imaging , Ultrasonography/methods , Image Interpretation, Computer-Assisted/methods , Deep Learning , Male , Female
8.
Pest Manag Sci ; 2024 Mar 06.
Article En | MEDLINE | ID: mdl-38446128

BACKGROUND: Potatoes, a major economic crop, are significantly impacted by Fusarium dry rot, a prevalent postharvest disease. Despite the broad-spectrum antimicrobial properties of cinnamaldehyde, a naturally-derived plant substance, its efficacy against the causal pathogen of potato dry rot (Fusarium oxysporum) and the underlying mechanisms have not been extensively studied. RESULTS: Our study demonstrates that cinnamaldehyde effectively inhibits the growth of Fusarium oxysporum, the pathogen responsible for potato dry rot, and increases its sensitivity to environmental stress factors such as extreme temperatures and high salt stress. Treatment with cinnamaldehyde results in altered fungal mycelium morphology, compromised cell wall stability, and disrupted cell membrane integrity, thereby reducing spore viability. Specifically, it interferes with the cell membrane and cell wall structures of the fungus, potentially disrupting fungal growth by modulating signaling pathways involved in cell wall maintenance, chitin metabolism, and GPI-anchored protein function. Notably, we show that cinnamaldehyde induces a form of regulated cell death in F. oxysporum, which is characterized not as typical apoptosis, as evidenced by Annexin V negative staining. However, the specific cell death type and underlying mechanism still needed to be further explored. CONCLUSION: Cinnamaldehyde, an environmentally friendly plant-based active compound, exhibits strong inhibitory effects on F. oxysporum, indicating its potential use in the prevention and control strategies for potato dry rot. This research contributes to the understanding of novel antifungal mechanisms and offers promising insights into eco-friendly alternatives for managing this economically significant postharvest disease. © 2024 Society of Chemical Industry.

9.
Transl Oncol ; 44: 101937, 2024 Jun.
Article En | MEDLINE | ID: mdl-38547613

BACKGROUND: Soft tissue sarcoma, a malignant tumor arising from mesenchymal tissues with poor prognosis. 5'-Nucleotidase Domain Containing 2 (NT5DC2) is a novel oncogene, and the precise involvement of NT5DC2 in soft tissue sarcoma were still undefined. Hence, our study aims to investigate NT5DC2 functions in soft tissue sarcoma progression. METHODS: The tumor immune single-cell hub 2 (TISCH2) website, The Cancer Genome Atlas (TCGA) pan-cancer or sarcoma and Gene Expression Omnibus (GEO, GSE21122) databases were applied to visualize the NT5DC2 status in the sarcoma databases. The NT5DC2 protein expression in sarcoma tissues in our hospital was detected by using immunohistochemistry (IHC) and analyzed the associations between NT5DC2 expression and clinicopathological parameters. Real-time quantitative polymerase chain reaction (RT-qPCR), colony formation, 5-ethynyl-2'-deoxyuridine (EdU) assay, wound healing, transwell, flow cytometry and xenograft model were used to elucidate the effects of NT5DC2 downregulated by lentivirus in sarcoma cell. RESULTS: The TISCH2 website detection found that NT5DC2 expression is enriched in malignant cells in sarcoma single-cell database. Furthermore, the TCGA-sarcoma database indicated that NT5DC2 expression correlates with metastasis, positive margin status, prognosis, and diagnostic value. Additionally, IHC staining showed that 40 % of soft tissue sarcoma patients present high expression of NT5DC2, and NT5DC2 upregulation is closely associated with poor prognosis. Functional verification analysis further revealed that downregulating NT5DC2 expression can suppress sarcoma progression through the ECM-receptor interaction pathway. CONCLUSION: Low expression of NT5DC2 predicts a favorable prognosis in soft tissue sarcoma, and downregulated NT5DC2 expression can suppress sarcoma cell progression through the ECM-receptor interaction pathway.

10.
J Cancer ; 15(8): 2306-2317, 2024.
Article En | MEDLINE | ID: mdl-38495481

Bicalutamide (BIC) resistance impedes the treatment of prostate cancer (PCa) and seems to involve ferroptosis; however, the underlying mechanism remains unclear. Our study aimed to explore how miR-15b-3p modulates ferroptosis in response to BIC resistance and determine whether the miRNA is suitable for early screening of PCa. Here, we found that PCa tissues had significantly higher miR-15b-3p expression than adjacent normal tissues. Analysis of blood samples in patients who underwent prostate-specific antigen (PSA) screening revealed that miR-15b-3p was a more accurate diagnostic than PSA (miR-15b-3p area under the curve [AUC] = 0.941, PSA AUC = 0.815). In vitro experiments then demonstrated that miR-15b-3p expression was markedly higher in LNCaP, PC-3, and DU145 cells than in RWPE-1 cells. Treatment with BIC decreased miR-15b-3p expression and progressive ferroptosis. Mechanistically, we identified KLF2 as the downstream target of miR-15b-3p. Overexpressing KLF2 facilitated ferroptosis via augmenting MDA and iron concentrations, in turn inhibiting the SLC7A11/GPX4 axis and decreasing GSH concentration. Through modulating ferroptosis, miR-15b-3p mimic and inhibitor weakened and enhanced BIC sensitivity, respectively. Furthermore, BIC treatment limited xenograft tumor volume in vivo, whereas agomir-15b-3p promoted tumor growth, indicating that miR-15b-3p attenuated the tumor-suppressive effects of BIC. Taken together, our results suggested that miR-15b-3p is crucial to BIC resistance, specifically via targeting KLF2 and thereby suppressing ferroptosis. High miR-15b-3p expression in early PCa screening should reflect a higher probability of cancer. In conclusion, miR-15b-3p has strong potential as a screening and diagnostic biomarker with reliable prospects for clinical application. Furthermore, because patients with high miR-15b-3p and low KLF2 expression have a greater risk of BIC resistance and malignant progression, targeting the miRNA and its downstream protein may be a new treatment strategy.

11.
Sci Rep ; 14(1): 6720, 2024 03 20.
Article En | MEDLINE | ID: mdl-38509215

The incidence of acute kidney injury (AKI) due to ischemia-reperfusion (IR) injury is increasing. There is no effective treatment for AKI, and because of this clinical challenge, AKI often progresses to chronic kidney disease, which is closely associated with poor patient outcomes and high mortality rates. Small extracellular vesicles from human umbilical cord mesenchymal stem cells (hUCMSC-sEVs) play increasingly vital roles in protecting tissue function from the effects of various harmful stimuli owing to their specific biological features. In this study, we found that miR-100-5p was enriched in hUCMSC-sEVs, and miR-100-5p targeted FKBP5 and inhibited HK-2 cell apoptosis by activating the AKT pathway. HK-2 cells that were exposed to IR injury were cocultured with hUCMSC-sEVs, leading to an increase in miR-100-5p levels, a decrease in FKBP5 levels, and an increase in AKT phosphorylation at Ser 473 (AKT-473 phosphorylation). Notably, these effects were significantly reversed by transfecting hUCMSCs with an miR-100-5p inhibitor. Moreover, miR-100-5p targeted FKBP5, as confirmed by a dual luciferase reporter assay. In vivo, intravenous infusion of hUCMSC-sEVs into mice suffering from IR injury resulted in significant apoptosis inhibition, functional maintenance and renal histological protection, which in turn decreased FKBP5 expression levels. Overall, this study revealed an effect of hUCMSC-sEVs on inhibiting apoptosis; hUCMSC-sEVs reduced renal IR injury by delivering miR-100-5p to HK-2 cells, targeting FKBP5 and thereby promoting AKT-473 phosphorylation to activate the AKT pathway. This study provides novel insights into the role of hUCMSC-sEVs in the treatment of AKI.


Acute Kidney Injury , Exosomes , Extracellular Vesicles , Mesenchymal Stem Cells , MicroRNAs , Reperfusion Injury , Humans , Mice , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Exosomes/metabolism , Acute Kidney Injury/pathology , Reperfusion Injury/genetics , Reperfusion Injury/therapy , Reperfusion Injury/metabolism , Extracellular Vesicles/metabolism , Mesenchymal Stem Cells/metabolism
12.
Clin Transl Med ; 14(2): e1586, 2024 02.
Article En | MEDLINE | ID: mdl-38372422

BACKGROUND: Osteosarcoma (OSA) presents a clinical challenge and has a low 5-year survival rate. Currently, the lack of advanced stratification models makes personalized therapy difficult. This study aims to identify novel biomarkers to stratify high-risk OSA patients and guide treatment. METHODS: We combined 10 machine-learning algorithms into 101 combinations, from which the optimal model was established for predicting overall survival based on transcriptomic profiles for 254 samples. Alterations in transcriptomic, genomic and epigenomic landscapes were assessed to elucidate mechanisms driving poor prognosis. Single-cell RNA sequencing (scRNA-seq) unveiled genes overexpressed in OSA cells as potential therapeutic targets, one of which was validated via tissue staining, knockdown and pharmacological inhibition. We characterized changes in multiple phenotypes, including proliferation, colony formation, migration, invasion, apoptosis, chemosensitivity and in vivo tumourigenicity. RNA-seq and Western blotting elucidated the impact of squalene epoxidase (SQLE) suppression on signalling pathways. RESULTS: The artificial intelligence-derived prognostic index (AIDPI), generated by our model, was an independent prognostic biomarker, outperforming clinicopathological factors and previously published signatures. Incorporating the AIDPI with clinical factors into a nomogram improved predictive accuracy. For user convenience, both the model and nomogram are accessible online. Patients in the high-AIDPI group exhibited chemoresistance, coupled with overexpression of MYC and SQLE, increased mTORC1 signalling, disrupted PI3K-Akt signalling, and diminished immune infiltration. ScRNA-seq revealed high expression of MYC and SQLE in OSA cells. Elevated SQLE expression correlated with chemoresistance and worse outcomes in OSA patients. Therapeutically, silencing SQLE suppressed OSA malignancy and enhanced chemosensitivity, mediated by cholesterol depletion and suppression of the FAK/PI3K/Akt/mTOR pathway. Furthermore, the SQLE-specific inhibitor FR194738 demonstrated anti-OSA effects in vivo and exhibited synergistic effects with chemotherapeutic agents. CONCLUSIONS: AIDPI is a robust biomarker for identifying the high-risk subset of OSA patients. The SQLE protein emerges as a metabolic vulnerability in these patients, providing a target with translational potential.


Bone Neoplasms , Osteosarcoma , Squalene Monooxygenase , Humans , Artificial Intelligence , Biomarkers , Osteosarcoma/drug therapy , Osteosarcoma/genetics , Phosphatidylinositol 3-Kinases , Prognosis , Proto-Oncogene Proteins c-akt , Squalene Monooxygenase/genetics , Squalene Monooxygenase/metabolism
13.
Molecules ; 29(3)2024 Jan 27.
Article En | MEDLINE | ID: mdl-38338363

In this study, we synthesized a coumarin-hemicyanine-based deep red fluorescent dye that exhibits an intramolecular charge transfer (ICT). The probe had a large Stokes shift of 287 nm and a large molar absorption coefficient (ε = 7.5 × 105 L·mol-1·cm-1) and is best described as a deep red luminescent fluorescent probe with λem = 667 nm. The color of probe W changed significantly when it encountered cyanide ions (CN-). The absorption peak (585 nm) decreased gradually, and the absorption peak (428 nm) increased gradually, so that cyanide (CN-) could be identified by the naked eye. Moreover, an obvious fluorescence change was evident before and after the reaction under irradiation using 365 nm UV light. The maximum emission peak (667 nm) decreased gradually, whilst the emission peak (495 nm) increased gradually, which allowed for the proportional fluorescence detection of cyanide (CN-). Using fluorescence spectrometry, the fluorescent probe W could linearly detect CN- over the concentration range of 1-9 µM (R2 = 9913, RSD = 0.534) with a detection limit of 0.24 µM. Using UV-Vis spectrophotometry, the linear detection range for CN- was found to be 1-27 µM (R2 = 0.99583, RSD = 0.675) with a detection limit of 0.13 µM. The sensing mechanism was confirmed by 1H NMR spectroscopic titrations, 13C NMR spectroscopy, X-ray crystallographic analysis and HRMS. The recognition and detection of CN- by probe W was characterized by a rapid response, high selectivity, and high sensitivity. Therefore, this probe provides a convenient, effective and economical method for synthesizing and detecting cyanide efficiently and sensitively.


Cyanides , Fluorescent Dyes , Cyanides/chemistry , Fluorescent Dyes/chemistry , Carbocyanines , Coumarins/chemistry , Spectrometry, Fluorescence/methods
14.
Transl Androl Urol ; 13(1): 1-24, 2024 Jan 31.
Article En | MEDLINE | ID: mdl-38404554

Background: Clear cell renal cell carcinoma (ccRCC) is one of the most common cancers worldwide, and its incidence is increasing every year. Endoplasmic reticulum stress (ERS) caused by protein misfolding has broad and profound effects on the progression and metastasis of various cancers. Accumulating evidence suggests that ERS is closely related to the occurrence and progression of ccRCC. This study aimed to identify ERS-related genes for evaluating the prognosis of ccRCC. Methods: Transcriptomic expression profiles were obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA), and clinical data were downloaded from the TCGA. First, the differentially expressed genes (DEGs) were analyzed using the limma package, and the DEGs related to ERS (ERS-DEGs) were identified from the GeneCards database. Second, a function and pathway enrichment analysis and a Gene Set Enrichment Analysis (GSEA) were performed. Third, a protein-protein interaction (PPI) network was constructed to identify the hub genes, and a gene-micro RNA (miRNA) network and gene-transcription factor (TF) network were established using the hub genes. Finally, a least absolute shrinkage and selection operator (LASSO) regression analysis was conducted to establish a diagnostic model, and a Cox analysis was used to analyze the correlations between the expression of the characteristic genes and the clinical characteristics. Results: We identified 11 signature genes and established a diagnostic model. Further, the Cox analysis results revealed a correlation between the expression levels of the signature genes and the clinical characteristics. Ultimately, five signature genes (i.e., TNFSF13B, APOL1, COL5A3, and CDH5) were found to be associated with a poor prognosis. Conclusions: This study suggests that TNFSF13B, APOL1, COL5A3, and CDH5 may have potential as prognostic biomarkers in ccRCC and may provide new evidence to support targeted therapy in ccRCC.

15.
Angew Chem Int Ed Engl ; 63(4): e202314228, 2024 Jan 22.
Article En | MEDLINE | ID: mdl-38019184

Axially chiral diaryl ethers are present in numerous natural products and bioactive molecules. However, only few catalytic enantioselective approaches have been established to access diaryl ether atropisomers. Herein, we report the N-heterocyclic carbene-catalyzed enantioselective synthesis of axially chiral diaryl ethers via desymmetrization of prochiral 2-aryloxyisophthalaldehydes with aliphatic alcohols, phenol derivatives, and heteroaromatic amines. This reaction features mild reaction conditions, good functional group tolerance, broad substrate scope and excellent enantioselectivity. The utility of this methodology is illustrated by late-stage functionalization, gram-scale synthesis, and diverse enantioretentive transformations. Control experiments and DFT calculations support the association of NHC-catalyzed desymmetrization with following kinetic resolution to enhance the enantioselectivity.

16.
Chemosphere ; 350: 140979, 2024 Feb.
Article En | MEDLINE | ID: mdl-38141673

Open biomass burning (OBB) is one of the largest primary emission sources for atmospheric carbonyl compounds, key precursors for ozone and secondary organic aerosol pollution. To clarify the carbonyl emissions, the comprehensive characteristics of C1-C10 carbonyl compounds from open burning of seven typical subtropical biomass in China were investigated in this study, which included subtropical plants and agricultural residues. Total 27 carbonyl compounds were detected. The total EFs were 2824 mg kg-1 with 95% confidence interval (CI) [2418, 3322] for burning subtropical plants and 4080 mg kg-1 with 95% CI [3446, 4724] for burning agriculture residues, respectively. The EFs were 2-3 orders of magnitude larger than previous values in China. Aliphatic aldehydes were the largest group of carbonyl groups, with acetaldehyde, as the most abundant carbonyl species (about 30% contribution). Formaldehyde, acetone, acrolein, glyoxal, methylglyoxal, butanone, isovaleraldehyde, and m-tolualdehyde were also found to be abundant and varying with the types of biomass burnt. Formaldehyde emission ratios to acetonitrile and CO were lower than those in previous studies both for burning plants and agricultural residues. There were significant variabilities in the emission ratios and factors among different types of OBBs. Strong positive correlations were found between carbonyl emissions and CO emissions and water content in biomass; furthermore, total carbonyl concentrations measured in the flaming stage were higher than those in the smoldering one. This study provides important fundamental measurement data on carbonyl emissions from burning typical subtropical plants and agricultural residues, which will help improve the quality of emission inventories and better understand the potential impacts of OBB on regional air quality in southern China.


Air Pollutants , Air Pollutants/analysis , Biomass , Open Waste Burning , China , Formaldehyde , Environmental Monitoring , Particulate Matter/analysis
17.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Article En | MEDLINE | ID: mdl-38081275

Here, we report our recent progress in the design, fluid thermodynamics simulation, and high-power test of the2nd harmonic cavity for the China Spallation Neutron Source Phase II. A high-performance and large-size magnetic alloy (MA) core was developed as the load material for the radiofrequency cavity to achieve a high gradient of 40 kV/m. The water-cooling structure and cooling efficiency were studied and improved through numerical analysis and thermal experiments. The long-term stability of the cavity, especially the waterproofness of the MA cores with high heat load, was verified by high power tests.

18.
Article En | MEDLINE | ID: mdl-38083321

Although numerous studies have been conducted on cuffless blood pressure (BP) estimation using machine learning methods, most of the data-driven models are static, with model parameters fixed after training is complete. However, BP is dynamic and the performance would degrade for a static model when the to-be predicted BP distribution deviates from the training BP distribution. In this paper, we propose a continual learning (CL) framework in which deep learning models are developed to learn dynamically and continuously for arterial BP (ABP) estimation with photoplethysmography (PPG) and electrocardiogram (ECG) waveforms. The effectiveness of the CL model is validated on UCI Repository and MIMIC-III database with a total of 132 individual samples, and compared with conventional training method. It was found that the CL model improved the ABP estimation accuracy in terms of mean absolute error (MAE) by 17.47% on average compared with conventional training model. Furthermore, the improvement increased with the variability of ABP. These results demonstrate that CL model has potential to estimate dynamic ABP, which has been challenging with conventional training.


Blood Pressure Determination , Photoplethysmography , Blood Pressure , Photoplethysmography/methods , Blood Pressure Determination/methods , Machine Learning , Electrocardiography
19.
Article En | MEDLINE | ID: mdl-38099323

Surgery is highly recommended for a bony mallet finger when the fracture fragment involves greater than one-third of the articular surface. K-wire based and plated-based internal fixation are widely used for mallet fracture. However, the outcomes of different surgical treatment options make the treatment of the bony mallet finger controversial due to frequent complications. The two-hole miniplate is a new and promising plate-based internal fixation treatment for the bony mallet finger with low complication rates in recent years. The aim of this study was to evaluate the biomechanical parameters (von Mises stress, strain and deformation) of the two-hole miniplate fixation compared to the traditional K-wire-based fixation using finite element analysis (FEA). Further, the biomechanical parameters of each part of the two-hole miniplate internal fixation were also analyzed. The results indicated that the two-hole miniplate model had the minimum von Mises stress value and the displacement of fracture fragment was less than 30 µm. The two-hole miniplate had an apparent compression effect on the avulsion fracture and inhibited the fracture displacement. This study would provide further guidance for clinical application in using the two-hole miniplate internal fixation.

20.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Article En | MEDLINE | ID: mdl-38117197

The utilization of a low-frequency (<200 MHz) RF system in storage facilitates the attainment of ultra-low emittances in synchrotron light sources through on-axis injection. This paper focuses on the development of a low-frequency normal conducting (NC) cavity with higher-order mode (HOM) damping for fourth-generation synchrotron light sources. We propose a novel approach to achieve efficient HOM damping in a NC cavity by optimizing the lowest frequency HOM and implementing a beam-line absorber. Notably, unlike conventional NC cavities, the presence of a large beam tube for the beam-line absorber does not compromise the accelerating performance in a coaxial resonant cavity, enabling effective HOM damping while maintaining a high shunt impedance. Through simulations, the prototype design of a 166.6 MHz HOM-damped cavity demonstrates a fundamental mode impedance of ∼8 MΩ, with longitudinal and transverse HOM impedances below 2.0 and 50 kΩ/m, respectively.

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