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1.
Sleep Med ; 119: 234-243, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38704871

RESUMEN

STUDY OBJECTIVES: Increased reactive oxygen species associated with loss of mitochondrial function affect synaptic activity, which is an important mechanism underlying cognitive decline. This study assesses the role of mitochondrial proteins in neuron-derived exosomes (NDEs) on cognitive impairment in patients with obstructive sleep apnea (OSA) without dementia. METHODS: Analyses were conducted in 268 study participants with complete polysomnography data, cognitive tests, and important clinical data available. NDEs were isolated immunochemically for enzyme-linked immunosorbent assay quantification of mitochondrial proteins, i.e., humanin and mitochondrial open reading frame of the 12S rRNA-c (MOTS-c), and synaptic protein, i.e., neurogranin (NRGN). A mediation analysis of the relationship between sleep parameters and cognition was performed using humanin, MOTS-c, and NRGN values as a mediating factor. Twenty-two patients with moderate to severe OSA who received CPAP therapy were followed up, and humanin, MOTS-c and NRGN levels were reassessed after 1 year of treatment. RESULTS: All participants were divided into the OSA + MCI group (n = 91), OSA-MCI group (n = 89), MCI group (MCI without OSA) (n = 38) and control group (normal cognitive state without OSA) (n = 50). The mean CD63-normalized NDE levels of humanin, MOTS-c, and NRGN in the OSA + MCI group were higher than those in the OSA-MCI and control groups. The NDE levels of humanin, MOTS-c, and NRGN in the MCI group were lower than those in controls. The odds of cognitive impairment in patients with OSA were higher with higher NDE levels of humanin, MOTS-c, and NRGN (odds ratio (OR): 2.100, 95 % confidence interval (CI): 1.646-2.679, P < 0.001; OR: 5.453, 95 % CI: 3.112-9.556, P < 0.001; OR: 3.115, 95 % CI: 2.163-4.484, P < 0.001). The impaired cognitive performance was associated with higher NDE levels of humanin (ß: 0.505, SE: 0.048, P < 0.001), MOTS-c (ß: 0.580, SE: 0.001, P < 0.001), and NRGN (ß: 0.585, SE: 0.553, P < 0.001). The relationship between sleep parameters (mean SaO2 and T90) and MoCA scores was mediated by the NDE levels of humanin, MOTS-c, and NRGN with the proportion of mediation varying from 35.33 % to 149.07 %. Receiver operating characteristic curve revealed an area under the curve of 0.905 for humanin, 0.873 for MOTS-c, and 0.934 for NRGN to predict MCI in OSA patients without dementia. Increased humanin, MOTS-c, and NRGN levels significantly decreased after CPAP treatment. CONCLUSIONS: Mitochondrial dysfunction is implicated in cognitive impairment in OSA patients without dementia, and mainly mediates the association between intermittent hypoxia and cognitive impairment in adults with OSA without dementia. Mitochondrial dysfunction can be partially reversible by CPAP treatment. Mitochondrial proteins can be used as markers of cognitive impairment in patients with OSA.

3.
J Org Chem ; 89(8): 5423-5433, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38557074

RESUMEN

Currently, most conventional methods to achieve imidazo[1,5-a]pyridines have limitations for the synthesis of 3-acyl imidazo[1,5-a]pyridines. Herein, a novel and efficient Cu(I)-catalyzed three-component annulation method for the synthesis of valuable 3-acyl imidazo[1,5-a]pyridines by the reaction of 2-pyridinyl-substituted p-QMs, terminal alkynes, and TsN3 in the presence of O2 under mild conditions have successfully been developed. The investigation indicated that molecular oxygen (O2) and TsN3, respectively, serving as oxygen and nitrogen sources, were essential for the successful completion of the reaction system.

4.
Cell Prolif ; : e13639, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553796

RESUMEN

Aneuploidy frequently occurs in cancer and developmental diseases such as Down syndrome, with its functional consequences implicated in dosage effects on gene expression and global perturbation of stress response and cell proliferation pathways. However, how aneuploidy affects spatial genome organization remains less understood. In this study, we addressed this question by utilizing the previously established isogenic wild-type (WT) and trisomic mouse embryonic stem cells (mESCs). We employed a combination of Hi-C, RNA-seq, chromosome painting and nascent RNA imaging technologies to compare the spatial genome structures and gene transcription among these cells. We found that trisomy has little effect on spatial genome organization at the level of A/B compartment or topologically associating domain (TAD). Inter-chromosomal interactions are associated with chromosome regions with high gene density, active histone modifications and high transcription levels, which are confirmed by imaging. Imaging also revealed contracted chromosome volume and weakened transcriptional activity for trisomic chromosomes, suggesting potential implications for the transcriptional output of these chromosomes. Our data resources and findings may contribute to a better understanding of the consequences of aneuploidy from the angle of spatial genome organization.

5.
J Neurosci Methods ; 405: 110108, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38458260

RESUMEN

BACKGROUND: Motor-Imagery-based Brain-Computer Interface (MI-BCI) is a promising technology to assist communication, movement, and neurological rehabilitation for motor-impaired individuals. Electroencephalography (EEG) decoding techniques using deep learning (DL) possess noteworthy advantages due to automatic feature extraction and end-to-end learning. However, the DL-based EEG decoding models tend to show large variations due to intersubject variability of EEG, which results from inconsistencies of different subjects' optimal hyperparameters. NEW METHODS: This study proposes a multi-branch multi-attention mechanism EEGNet model (MBMANet) for robust decoding. It applies the multi-branch EEGNet structure to achieve various feature extractions. Further, the different attention mechanisms introduced in each branch attain diverse adaptive weight adjustments. This combination of multi-branch and multi-attention mechanisms allows for multi-level feature fusion to provide robust decoding for different subjects. RESULTS: The MBMANet model has a four-classification accuracy of 83.18% and kappa of 0.776 on the BCI Competition IV-2a dataset, which outperforms other eight CNN-based decoding models. This consistently satisfactory performance across all nine subjects indicates that the proposed model is robust. CONCLUSIONS: The combine of multi-branch and multi-attention mechanisms empowers the DL-based models to adaptively learn different EEG features, which provides a feasible solution for dealing with data variability. It also gives the MBMANet model more accurate decoding of motion intentions and lower training costs, thus improving the MI-BCI's utility and robustness.


Asunto(s)
Interfaces Cerebro-Computador , Humanos , Electrodiagnóstico , Intención , Movimiento (Física) , Movimiento , Electroencefalografía , Algoritmos
6.
Diabetes Metab Syndr Obes ; 17: 997-1011, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435631

RESUMEN

Background: The pathological damage mechanism of type 2 diabetes (T2D) and macroangiopathy is extremely complex, and T2D and arteriosclerosis obliterans have different biological behaviors and clinical features. To explore the mechanism of lower extremity arteriosclerosis occlusion (LEAOD) in T2D patients, we utilized RNA-seq to identify unique gene expression signatures of T2D and LEAOD through transcriptomic analysis. Methods: We obtained blood samples and performed RNA sequencing from four patients with T2D, five of whom had LEAOD. Another six age- and gender-matched blood samples from healthy volunteers were used for control. By exploring the general and specific differential expression analysis after transcriptome sequencing, specific gene expression patterns of T2D and LEAOD were verified. Results: Transcriptome analysis found differentially expressed genes in T2D, and T2D + LEAOD (vs normal) separately, of which 35/486 (T2D/T2D + LEAOD) were up-regulated and 1290/2970 (T2D/T2D + LEAOD) were down-regulated. A strong overlap of 571 genes across T2D, LEAOD, and coexisting conditions was mainly involved in extracellular exosomes and the transcription process. By exploring the sex difference gene expression features between T2D, T2D + LEAOD, and healthy controls, we noticed that sex chromosome-associated genes do not participate in the sexual dimorphism gene expression profiles of T2D and LEAOD. Protein-Protein Interaction Network analysis and drug target prediction provided the drug candidates to treat T2D and LEAOD. Conclusion: This study provides some evidence at the transcript level to uncover the association of T2D with LEAOD. The screened hub genes and predicted target drugs may be therapeutic targets.

7.
Heliyon ; 10(2): e24598, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38312602

RESUMEN

Background: Diabetic foot ulcers (DFUs) are a severe complication of diabetes. Persistent inflammation and impaired vascularization present considerable challenges in tissue wound healing. The aim of this study was to identify the crucial regulators of DFU wound healing and investigate their specific mechanisms in DFU. Methods: DFU RNA sequencing data were obtained to identify crucial feature genes. The expression levels of the feature genes and their corresponding microRNAs (miRNAs) were verified in clinical samples. Subsequently, the expression of CD68 was determined in DFU and non-diabetic foot skin samples. RAW 264.7 cells were treated with advanced glycation end products (AGEs) to determine their viability and apoptosis. Finally, the roles of the selected crucial genes and their corresponding miRNAs were investigated using in vitro experiments and a mouse model of diabetes. Results: Bioinformatic analysis showed that five crucial feature genes (CORO1A, CSF1R, CTSH, NFE2L3, and SLC16A10) were associated with DFU wound healing. The expression validation showed that miR-361-3p-CSF1R had a significant negative correlation and was thus selected for further experiments. AGEs significantly inhibited the viability of RAW 264.7 cells and enhanced their apoptosis; furthermore, the AGEs significantly downregulated CSF1R and increased miR-361-3p levels compared with the control cells. Additionally, inhibition of miR-361-3p decreased the cell apoptosis caused by AGEs and increased the levels of p-AKT/AKT and p-PI3K/PI3K, whereas CSF1R knockdown reversed the effects of miR-361-3p. In vivo experiments showed that miR-361-3p inhibition promoted wound healing in diabetic mice and regulated PI3K/AKT levels. Conclusions: AGEs may regulate macrophage apoptosis via the miR-361-3p/CSF1R axis and PI3K/AKT pathway, thereby influencing DFU wound healing.

8.
Cell Oncol (Dordr) ; 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38315283

RESUMEN

PURPOSE: Microbial dysbiosis is considered as a hallmark of colorectal cancer (CRC). Trimethylamine-N-oxide (TMAO) as a gut microbiota-dependent metabolite has recently been implicated in CRC development. Nevertheless, evidence relating TMAO to intestinal carcinogenesis remains largely unexplored. Herein, we aimed to examine the crucial role of TMAO in CRC progression. METHODS: Apcmin/+ mice were treated with TMAO or sterile PBS for 14 weeks. Intestinal tissues were isolated to evaluate the effects of TMAO on the malignant transformation of intestinal adenoma. The gut microbiota of mouse feces was detected by 16S rRNA sequencing analysis. HCT-116 cells were used to provide further evidence of TMAO on the progression of CRC. RESULTS: TMAO administration increased tumor cell and stem cell proliferation, and decreased apoptosis, accompanied by DNA damage and gut barrier impairment. Gut microbiota analysis revealed that TMAO induced changes in the intestinal microbial community structure, manifested as reduced beneficial bacteria. Mechanistically, TMAO bound to farnesoid X receptor (FXR), thereby inhibiting the FXR-fibroblast growth factor 15 (FGF15) axis and activating the Wnt/ß-catenin signaling pathway, whereas the FXR agonist GW4064 could blunt TMAO-induced Wnt/ß-catenin pathway activation. CONCLUSION: The microbial metabolite TMAO can enhance intestinal carcinogenesis by inhibiting the FXR-FGF15 pathway.

9.
J Neural Eng ; 21(1)2024 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-38359457

RESUMEN

Objective. Motor imagery-based brain-computer interaction (MI-BCI) is a novel method of achieving human and external environment interaction that can assist individuals with motor disorders to rehabilitate. However, individual differences limit the utility of the MI-BCI. In this study, a personalized MI prediction model based on the individual difference of event-related potential (ERP) is proposed to solve the MI individual difference.Approach.A novel paradigm named action observation-based multi-delayed matching posture task evokes ERP during a delayed matching posture task phase by retrieving picture stimuli and videos, and generates MI electroencephalogram through action observation and autonomous imagery in an action observation-based motor imagery phase. Based on the correlation between the ERP and MI, a logistic regression-based personalized MI prediction model is built to predict each individual's suitable MI action. 32 subjects conducted the MI task with or without the help of the prediction model to select the MI action. Then classification accuracy of the MI task is used to evaluate the proposed model and three traditional MI methods.Main results.The personalized MI prediction model successfully predicts suitable action among 3 sets of daily actions. Under suitable MI action, the individual's ERP amplitude and event-related desynchronization (ERD) intensity are the largest, which helps to improve the accuracy by 14.25%.Significance.The personalized MI prediction model that uses the temporal ERP features to predict the classification accuracy of MI is feasible for improving the individual's MI-BCI performance, providing a new personalized solution for the individual difference and practical BCI application.


Asunto(s)
Interfaces Cerebro-Computador , Individualidad , Humanos , Imaginación , Potenciales Evocados , Electroencefalografía/métodos
10.
J Agric Food Chem ; 72(8): 4155-4169, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38366990

RESUMEN

In this study, we used traditional laboratory methods, bioinformatics, and cellular models to screen novel ACE inhibitory (ACEI) peptides with strong ACEI activity, moderate absorption rates, and multiple targets from bovine colostrum immunoglobulin G (IgG). The purified fraction of the compound proteinase hydrolysate of IgG showed good ACEI activity. After nano-UPLC-MS/MS identification and in silico analysis, eight peptides were synthesized and verified. Among them, SFYPDY, TSFYPDY, FSWF, WYQQVPGSGL, and GVHTFP were identified as ACEI peptides, as they exhibited strong ACEI activity (with IC50 values of 104.7, 80.0, 121.2, 39.8, and 86.3 µM, respectively). They displayed good stability in an in vitro simulated gastrointestinal digestion assay. In a Caco-2 monolayer model, SFYPDY, FSWF, and WYQQVPGSGL exhibited better absorption rates and lower IC50 values than the other peptides and were thereby identified as novel ACEI peptides. Subsequently, in a H2O2-induced endothelial dysfunction (ED) model based on HUVECs, SFYPDY, FSWF, and WYQQVPGSGL regulated ED by reducing apoptosis and ROS accumulation while upregulating NOS3 mRNA expression. Network pharmacology analysis and RT-qPCR confirmed that they regulated multiple targets. Overall, our results suggest that SFYPDY, FSWF, and WYQQVPGSGL can serve as novel multitarget ACEI peptides.


Asunto(s)
Inmunoglobulina G , Enfermedades Vasculares , Humanos , Femenino , Embarazo , Animales , Bovinos , Farmacología en Red , Espectrometría de Masas en Tándem , Células CACO-2 , Calostro/metabolismo , Peróxido de Hidrógeno , Péptidos/química , Peptidil-Dipeptidasa A/química , Hidrolisados de Proteína/química , Simulación del Acoplamiento Molecular
11.
Artículo en Inglés | MEDLINE | ID: mdl-38165720

RESUMEN

INTRODUCTION: In type 2 diabetes mellitus (T2DM), orthostatic hypotension (OH) was associated with cognition, but the mechanisms governing the link between OH and cognition are still unclear. METHODS: We recruited T2DM with mild cognitive impairment (MCI) subjects, collected general healthy information and blood samples. Complement proteins of astrocyte-derived exosomes isolated and Alzheimer's disease (AD) biomarkers of neuronal cell-derived exosomes isolated were quantified by ELISA. Cognitive assessments were performed at patient enrollment and follow-up. RESULTS: Mediation analysis showed that the influence of OH on cognition in T2DM was partly mediated by baseline AD biomarkers and complement proteins. Cox proportional hazards regression proved OH group had a higher risk of developing dementia compared to T2DM without OH group. DISCUSSION: In T2DM with MCI patients, AD biomarkers and complement proteins mediate the effects of OH on cognitive impairment and OH may be a risk factor of progression from MCI to dementia in T2DM.

12.
Microbiome ; 12(1): 4, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172943

RESUMEN

BACKGROUND: The overgrowth of Desulfovibrio, an inflammation promoting flagellated bacteria, has been found in ulcerative colitis (UC) patients. However, the molecular mechanism in promoting colitis remains unestablished. METHODS: The relative abundance Desulfovibrio vulgaris (D. vulgaris) in stool samples of UC patients was detected. Mice were treated with dextran sulfate sodium to induce colitis with or without administration of D. vulgaris or D. vulgaris flagellin (DVF), and the severity of colitis and the leucine-rich repeat containing 19 (LRRC19) signaling were assessed. The interaction between DVF and LRRC19 was identified by surface plasmon resonance and intestinal organoid culture. Lrrc19-/- and Tlr5-/- mice were used to investigate the indispensable role of LRRC19. Finally, the blockade of DVF-LRRC19 interaction was selected through virtual screening and the efficacy in colitis was assessed. RESULTS: D. vulgaris was enriched in fecal samples of UC patients and was correlated with the disease severity. D. vulgaris or DVF treatment significantly exacerbated colitis in germ-free mice and conventional mice. Mechanistically, DVF could interact with LRRC19 (rather than TLR5) in colitis mice and organoids, and then induce the production of pro-inflammatory cytokines. Lrrc19 knockdown blunted the severity of colitis. Furthermore, typhaneoside, a blockade of binding interfaces, blocked DVF-LRRC19 interaction and dramatically ameliorated DVF-induced colitis. CONCLUSIONS: D. vulgaris could promote colitis through DVF-LRRC19 interaction. Targeting DVF-LRRC19 interaction might be a new therapeutic strategy for UC therapy. Video Abstract.


Asunto(s)
Colitis Ulcerosa , Colitis , Desulfovibrio vulgaris , Humanos , Ratones , Animales , Receptor Toll-Like 5/metabolismo , Receptor Toll-Like 5/uso terapéutico , Desulfovibrio vulgaris/metabolismo , Colitis/inducido químicamente , Colitis/metabolismo , Colitis Ulcerosa/microbiología , Inflamación/metabolismo , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Colon/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/uso terapéutico
13.
Nat Commun ; 15(1): 508, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38218946

RESUMEN

Stabilizing active PtNi alloy catalyst toward oxygen reduction reaction is essential for fuel cell. Doping of specific metals is an empirical strategy, however, the atomistic insight into how dopant boosts the stability of PtNi catalyst still remains elusive. Here, with typical examples of Mo and Au dopants, we identify the distinct roles of Mo and Au in stabilizing PtNi nanowires catalysts. Specifically, due to the stronger interaction between atomic orbital for Ni-Mo and Pt-Au, the Mo dopant mainly suppresses the outward diffusion of Ni atoms while the Au dopant contributes to the stabilization of surface Pt overlayer. Inspired by this atomistic understanding, we rationally construct the PtNiMoAu nanowires by integrating the different functions of Mo and Au into one entity. Such catalyst assembled in fuel cell cathode thus presents both remarkable activity and durability, even surpassing the United States Department of Energy technical targets for 2025.

14.
J Org Chem ; 89(3): 1692-1702, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38207341

RESUMEN

The products containing pyrimidine scaffolds exhibit various important physiological and biological activities. To date, the strategies to generate 4,5,6-trisubstituted pyrimidines were not reported. Here, a copper-catalyzed reaction of 2H-azirines with α-isocyanoacetates or α-isocyanoacetamides has been developed, rapidly preparing 4,5,6-trisubstituted pyrimidines. The mechanistic results reveal that this strategy underwent a formal 1, 3-dipolar [3 + 2] cycloaddition/ring-expanding/oxidative aromatization procedure to construct the desired pyrimidines.

15.
Redox Biol ; 70: 103055, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38290385

RESUMEN

Nanozymes with superior antioxidant properties offer new hope for treating oxidative stress-related inflammatory skin diseases. However, lacking sufficient catalytic activity or having complex material designs limit the application of current metallic nanozymes in inflammatory skin diseases. Here, we report a simple and effective twin-defect platinum nanowires (Pt NWs) enzyme with multiple mimetic enzymes and broad-spectrum ROS scavenging capability for the treatment of inflammatory skin diseases in mice (including psoriasis and rosacea). Pt NWs with simultaneous superoxide dismutase, glutathione peroxidase and catalase mimetic enzyme properties exhibit cytoprotective effects against ROS-mediated damage at extremely low doses and significantly improve treatment outcomes in psoriasis- and rosacea-like mice. Meanwhile, these ultrasmall sizes of Pt NWs allow the nanomaterials to effectively penetrate the skin and do not produce significant biotoxicity. Therefore, Pt NWs have potential applications in treating diseases related to oxidative stress or inflammation.


Asunto(s)
Dermatitis , Nanocables , Psoriasis , Rosácea , Animales , Ratones , Especies Reactivas de Oxígeno , Antioxidantes/farmacología
16.
J Nutr Biochem ; 125: 109494, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37866426

RESUMEN

Colorectal cancer (CRC) is currently the third leading cancer and commonly develops from chronic intestinal inflammation. A strong association was found between gut microbiota and intestinal inflammation and carcinogenic risk. Flavonoids, which are abundant in vegetables and fruits, can inhibit inflammation, regulate gut microbiota, protect gut barrier integrity, and modulate immune cell function, thereby attenuating colitis and preventing carcinogenesis. Upon digestion, about 90% of flavonoids are transported to the colon without being absorbed in the small intestine. This phenomenon increases the abundance of beneficial bacteria and enhances the production of short-chain fatty acids. The gut microbe further metabolizes these flavonoids. Interestingly, some metabolites of flavonoids play crucial roles in anti-inflammation and anti-tumor effects. This review summarizes the modulatory effect of flavonoids on gut microbiota and their metabolism by intestinal microbe under disease conditions, including inflammatory bowel disease, colitis-associated cancer (CAC), and CRC. We focus on dietary flavonoids and microbial interactions in intestinal mucosal barriers as well as intestinal immune cells. Results provide novel insights to better understand the crosstalk between dietary flavonoids and gut microbiota and support the standpoint that dietary flavonoids prevent intestinal inflammation and carcinogenesis.


Asunto(s)
Colitis , Microbiota , Humanos , Inflamación , Polifenoles , Flavonoides/farmacología , Carcinogénesis
17.
Med Biol Eng Comput ; 62(3): 675-686, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37982955

RESUMEN

Deep learning has great potential on decoding EEG in brain-computer interface. While common deep learning algorithms cannot directly train models with data from multiple individuals because of the inter-individual differences in EEG. Collecting enough data for each subject to satisfy the training of deep learning would result in an increase in training cost. This study proposes a novel transfer learning, EEGNet-based multi-source domain filter for transfer learning (EEGNet-MDFTL), to reduce the amount of training data and improve the performance of BCI. The EEGNet-MDFTL uses bagging ensemble learning to learn domain-invariant features from the multi-source domain and utilizes model loss value to filter the multi-source domain. Compared with baseline methods, the accuracy of the EEGNet-MDFTL reaches 91.96%, higher than two state-of-the-art methods, which demonstrates source domain filter can select similar source domains to improve the accuracy of the model, and remains a high level even when the data amount is reduced to 1/8, proving that ensemble learning learns enough domain invariant features from the multi-source domain to make the model insensitive to data amount. The proposed EEGNet-MDFTL is effective in improving the decoding performance with a small amount of data, which is helpful to save the BCI training cost.


Asunto(s)
Interfaces Cerebro-Computador , Humanos , Algoritmos , Aprendizaje Automático , Electroencefalografía
18.
Sci Rep ; 13(1): 21417, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-38049536

RESUMEN

With the advancement of society, ensuring the safety of personnel involved in municipal construction projects, particularly in the context of pandemic control measures, has become a matter of utmost importance. This paper introduces a security measure for municipal engineering, combining deep learning with object detection technology. It proposes a lightweight artificial intelligence (AI) detection method capable of simultaneously identifying individuals wearing masks and safety helmets. The method primarily incorporates the ShuffleNetv2 feature extraction mechanism within the framework of the YOLOv5s network to reduce computational overhead. Additionally, it employs the ECA attention mechanism and optimized loss functions to generate feature maps with more comprehensive information, thereby enhancing the precision of target detection. Experimental results indicate that this algorithm improves the mean average precision (mAP) value by 4.3%. Furthermore, it reduces parameter and computational loads by 54.8% and 53.8%, respectively, effectively striking a balance between lightweight operation and precision. This study serves as a valuable reference for research pertaining to lightweight target detection in the realm of municipal construction safety measures.


Asunto(s)
Inteligencia Artificial , Dispositivos de Protección de la Cabeza , Humanos , Algoritmos , Pandemias , Medidas de Seguridad
19.
Opt Express ; 31(25): 41219-41233, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38087526

RESUMEN

Limited by measurement methods, measuring the surfaces and thickness of large thin parallel plates has been challenging. In this paper, we propose a multi-dimensional stitching method using thickness alignment (MSuTA), which use the sub-aperture stitching method based on the phenomenon of parallel plate self-interference with wavelength-tuned interferometer (WTI) for measuring the surfaces and thickness of large thin parallel plates. We establish the stitching correction model based on Legendre polynomial to separate the aberrations caused by the elastic deformation of the thin plate in the unconstrained support tooling by analyzing the influence of the stress state of the thin plate with unconstrained three-point support. The stitching experiment has carried out on 6.3 mm thick, 6-inch parallel plates that the stitching residual is better than 0.35 nm RMS. Compared with 12-inch vertical interferometer, the surfaces and thickness deviation are better than 0.8 nm RMS, and the 36 standard Legendre polynomial coefficient deviation are better than 2.5 nm. Moreover, MSuTA can improves the lateral resolution of the measurement by nearly four times, allowing for a display of more comprehensive surface information. The stitching method proposed in this paper will be widely applied in the manufacture and measurement of large thin parallel plates, and provide reference for the elastic deformation analysis of the thin optical elements in the unconstrained support tooling.

20.
J Org Chem ; 88(22): 15696-15707, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37906125

RESUMEN

Cyanoacrylates have a wide range of biological activities and are extensively applied in production and daily life. Classic synthetic routes to cyanoacrylates have many limitations. Herein, we demonstrate an elemental sulfur-promoted method for the synthesis of ß,ß-diaryl cyanoacrylates by a tandem 1,6-Michael addition/oxidation/elimination process from p-QMs and cyanoacetates under optimal conditions. The effective protocol has good substrate scopes and yields, and the ratio of inseparable E/Z isomers of cyanoacrylates is also determined by 1HNMR.

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