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1.
Nature ; 626(7999): 523-528, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356068

RESUMEN

Spatial, momentum and energy separation of electronic spins in condensed-matter systems guides the development of new devices in which spin-polarized current is generated and manipulated1-3. Recent attention on a set of previously overlooked symmetry operations in magnetic materials4 leads to the emergence of a new type of spin splitting, enabling giant and momentum-dependent spin polarization of energy bands on selected antiferromagnets5-10. Despite the ever-growing theoretical predictions, the direct spectroscopic proof of such spin splitting is still lacking. Here we provide solid spectroscopic and computational evidence for the existence of such materials. In the noncoplanar antiferromagnet manganese ditelluride (MnTe2), the in-plane components of spin are found to be antisymmetric about the high-symmetry planes of the Brillouin zone, comprising a plaid-like spin texture in the antiferromagnetic (AFM) ground state. Such an unconventional spin pattern, further found to diminish at the high-temperature paramagnetic state, originates from the intrinsic AFM order instead of spin-orbit coupling (SOC). Our finding demonstrates a new type of quadratic spin texture induced by time-reversal breaking, placing AFM spintronics on a firm basis and paving the way for studying exotic quantum phenomena in related materials.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38733457

RESUMEN

The interaction between tumor programmed death ligand 1 (PD-L1) and T-cell programmed cell death 1 (PD-1) has long been acknowledged as a mechanism for evading immune surveillance. Recent studies, however, have unveiled a more nuanced role of tumor-intrinsic PD-L1 in reprograming tumoral phenotypes. Preclinical models emphasize the synchronized effects of both intracellular and extracellular PD-L1 in promoting metastasis, with intricate interactions with the immune system. This review aims to summarize recent findings to elucidate the spatiotemporal heterogeneity of PD-L1 expression and the pro-metastatic roles of PD-L1 in the entire process of tumor metastasis. For example, PD-L1 regulates the epithelial-to-mesenchymal transition (EMT) process, facilitates the survival of circulating tumor cells, and induces the formation of immunosuppressive environments at pre-metastatic niches and metastatic sites. And the complexed and dynamic regulation process of PD-L1 for tumor metastasis is related to the spatiotemporal heterogeneity of PD-L1 expression and functions from tumor primary sites to various metastatic sites. This review extends the current understandings for the roles of PD-L1 in mediating tumor metastasis and provides new insights into therapeutic decisions in clinical practice.

3.
Bioinformatics ; 40(1)2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38216534

RESUMEN

MOTIVATION: Transcription factor binding sites (TFBS) are regulatory elements that have significant impact on transcription regulation and cell fate determination. Canonical motifs, biological experiments, and computational methods have made it possible to discover TFBS. However, most existing in silico TFBS prediction models are solely DNA-based, and are trained and utilized within the same biosample, which fail to infer TFBS in experimentally unexplored biosamples. RESULTS: Here, we propose TFBS prediction by modified TransFormer (TFTF), a multimodal deep language architecture which integrates multiomics information in epigenetic studies. In comparison to existing computational techniques, TFTF has state-of-the-art accuracy, and is also the first approach to accurately perform genome-wide detection for cell-type and species-specific TFBS in experimentally unexplored biosamples. Compared to peak calling methods, TFTF consistently discovers true TFBS in threshold tuning-free way, with higher recalled rates. The underlying mechanism of TFTF reveals greater attention to the targeted TF's motif region in TFBS, and general attention to the entire peak region in non-TFBS. TFTF can benefit from the integration of broader and more diverse data for improvement and can be applied to multiple epigenetic scenarios. AVAILABILITY AND IMPLEMENTATION: We provide a web server (https://tftf.ibreed.cn/) for users to utilize TFTF model. Users can train TFTF model and discover TFBS with their own data.


Asunto(s)
Genoma , Multiómica , Sitios de Unión , Unión Proteica , Factores de Transcripción/metabolismo , Biología Computacional/métodos
4.
Mol Ther ; 32(1): 168-184, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37974400

RESUMEN

Circular mRNA (cmRNA) is particular useful due to its high resistance to degradation by exonucleases, resulting in greater stability and protein expression compared to linear mRNA. T cell receptor (TCR)-engineered T cells (TCR-T) represent a promising means of treating viral infections and cancer. This study aimed to evaluate the feasibility and efficacy of cmRNA in antigen-specific-TCR discovery and TCR-T therapy. Using human cytomegalovirus (CMV) pp65 antigen as a model, we found that the expansion of pp65-responsive T cells was induced more effectively by monocyte-derived dendritic cells transfected with pp65-encoding cmRNA compared with linear mRNA. Subsequently, we developed cmRNA-transduced pp65-TCR-T (cm-pp65-TCR-T) that specifically targets the CMV-pp65 epitope. Our results showed that pp65-TCR could be expressed on primary T cells for more than 7 days. Moreover, both in vitro killing and in vivo CDX models demonstrated that cm-pp65-TCR-T cells specifically and persistently kill pp65-and HLA-expressing tumor cells, significantly prolonging the survival of mice. Collectively, our results demonstrated that cmRNA can be used as a more effective technical approach for antigen-specific TCR isolation and identification, and cm-pp65-TCR-T may provide a safe, non-viral, non-integrated therapeutic approach for controlling CMV infection, particularly in patients who have undergone allogeneic hematopoietic stem cell transplantation.


Asunto(s)
Infecciones por Citomegalovirus , Trasplante de Células Madre Hematopoyéticas , Humanos , Animales , Ratones , Infecciones por Citomegalovirus/genética , Infecciones por Citomegalovirus/terapia , Citomegalovirus/genética , Linfocitos T , Receptores de Antígenos de Linfocitos T/genética , Proteínas de la Matriz Viral/genética
5.
Chem Soc Rev ; 53(7): 3350-3383, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38406832

RESUMEN

Super-resolution imaging has rapidly emerged as an optical microscopy technique, offering advantages of high optical resolution over the past two decades; achieving improved imaging resolution requires significant efforts in developing super-resolution imaging agents characterized by high brightness, high contrast and high sensitivity to fluorescence switching. Apart from technical requirements in optical systems and algorithms, super-resolution imaging relies on fluorescent dyes with special photophysical or photochemical properties. The concept of aggregation-induced emission (AIE) was proposed in 2001, coinciding with unprecedented advancements and innovations in super-resolution imaging technology. AIE probes offer many advantages, including high brightness in the aggregated state, low background signal, a larger Stokes shift, ultra-high photostability, and excellent biocompatibility, making them highly promising for applications in super-resolution imaging. In this review, we summarize the progress in implementation methods and provide insights into the mechanism of AIE-based super-resolution imaging, including fluorescence switching resulting from photochemically-converted aggregation-induced emission, electrostatically controlled aggregation-induced emission and specific binding-regulated aggregation-induced emission. Particularly, the aggregation-induced emission principle has been proposed to achieve spontaneous fluorescence switching, expanding the selection and application scenarios of super-resolution imaging probes. By combining the aggregation-induced emission principle and specific molecular design, we offer some comprehensive insights to facilitate the applications of AIEgens (AIE-active molecules) in super-resolution imaging.

6.
J Am Chem Soc ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38973592

RESUMEN

Platensilin, platensimycin, and platencin are potent inhibitors of ß-ketoacyl-acyl carrier protein synthase (FabF) in the bacterial and mammalian fatty acid synthesis system, presenting promising drug leads for both antibacterial and antidiabetic therapies. Herein, a bioinspired skeleton reconstruction approach is reported, which enables the unified synthesis of these three natural FabF inhibitors and their skeletally diverse analogs, all stemming from a common ent-pimarane core. The synthesis features a diastereoselective biocatalytic reduction and an intermolecular Diels-Alder reaction to prepare the common ent-pimarane core. From this intermediate, stereoselective Mn-catalyzed hydrogen atom-transfer hydrogenation and subsequent Cu-catalyzed carbenoid C-H insertion afford platensilin. Furthermore, the intramolecular Diels-Alder reaction succeeded by regioselective ring opening of the newly formed cyclopropane enables the construction of the bicyclo[3.2.1]-octane and bicyclo[2.2.2]-octane ring systems of platensimycin and platencin, respectively. This skeletal reconstruction approach of the ent-pimarane core facilitates the preparation of analogs bearing different polycyclic scaffolds. Among these analogs, the previously unexplored cyclopropyl analog 47 exhibits improved antibacterial activity (MIC80 = 0.0625 µg/mL) against S. aureus compared to platensimycin.

7.
J Magn Reson Imaging ; 59(3): 837-848, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37431848

RESUMEN

BACKGROUND: Native T1 and radiomics were used for hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD) differentiation previously. The current problem is that global native T1 remains modest discrimination performance and radiomics requires feature extraction beforehand. Deep learning (DL) is a promising technique in differential diagnosis. However, its feasibility for discriminating HCM and HHD has not been investigated. PURPOSE: To examine the feasibility of DL in differentiating HCM and HHD based on T1 images and compare its diagnostic performance with other methods. STUDY TYPE: Retrospective. POPULATION: 128 HCM patients (men, 75; age, 50 years ± 16) and 59 HHD patients (men, 40; age, 45 years ± 17). FIELD STRENGTH/SEQUENCE: 3.0T; Balanced steady-state free precession, phase-sensitive inversion recovery (PSIR) and multislice native T1 mapping. ASSESSMENT: Compare HCM and HHD patients baseline data. Myocardial T1 values were extracted from native T1 images. Radiomics was implemented through feature extraction and Extra Trees Classifier. The DL network is ResNet32. Different input including myocardial ring (DL-myo), myocardial ring bounding box (DL-box) and the surrounding tissue without myocardial ring (DL-nomyo) were tested. We evaluate diagnostic performance through AUC of ROC curve. STATISTICAL TESTS: Accuracy, sensitivity, specificity, ROC, and AUC were calculated. Independent t test, Mann-Whitney U-test and Chi-square test were adopted for HCM and HHD comparison. P < 0.05 was considered statistically significant. RESULTS: DL-myo, DL-box, and DL-nomyo models showed an AUC (95% confidential interval) of 0.830 (0.702-0.959), 0.766 (0.617-0.915), 0.795 (0.654-0.936) in the testing set. AUC of native T1 and radiomics were 0.545 (0.352-0.738) and 0.800 (0.655-0.944) in the testing set. DATA CONCLUSION: The DL method based on T1 mapping seems capable of discriminating HCM and HHD. Considering diagnostic performance, the DL network outperformed the native T1 method. Compared with radiomics, DL won an advantage for its high specificity and automated working mode. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2.


Asunto(s)
Cardiomiopatía Hipertrófica , Aprendizaje Profundo , Cardiopatías , Hipertensión , Masculino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos
8.
World J Urol ; 42(1): 29, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38214793

RESUMEN

PURPOSE: To evaluate the diagnostic ability of mpMRI, 68Ga-PSMA PET/CT and mpMRI combined with 68Ga-PSMA PET/CT in detecting and localizing lesions, and further clarify the accuracy of these examinations in tumor staging. METHODS: Seventy patients who underwent mpMRI, 68Ga-PSMA PET/CT and radical prostatectomy were enrolled. The abilities to detect index and clinically significant lesions by three examinations were compared. We further evaluated the ability of these examinations to localize lesions to the superior, inferior, anterior, posterior, left and right halves of the prostate and analyzed their accuracy in local and lymph node staging. RESULTS: There were no significant differences among mpMRI, 68Ga-PSMA PET/CT and mpMRI combined with 68Ga-PSMA PET/CT in their ability to detect index (p = 0.48, p = 0.23 and p = 0.07) and clinically significant lesions (p = 0.30, p = 0.29 and p = 0.06) or to localize lesions in six half divisions of the prostate. With postoperative pathology as reference, both mpMRI (p = 0.10) and mpMRI combined with 68Ga-PSMA PET/CT (p = 0.10) can accurately assess the local staging of prostate cancer. However, 68Ga-PSMA PET/CT underestimates the local staging of prostate cancer (p < 0.01). Regarding lymph node staging, the three types of examination showed no significant differences compared to postoperative pathology (p = 0.63, p = 0.51 and p = 0.14). CONCLUSIONS: With postoperative pathology as reference, 68Ga-PSMA PET/CT underestimates the local tumor staging. MpMRI combined with 68Ga-PSMA PET/CT has no obvious advantages in detecting, localizing or staging prostate cancer compared with mpMRI.


Asunto(s)
Radioisótopos de Galio , Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Masculino , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Isótopos de Galio
9.
Physiol Plant ; 176(2): e14272, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566275

RESUMEN

The Dehydration-Responsive Element Binding (DREB) subfamily of transcription factors plays crucial roles in plant abiotic stress response. Ammopiptanthus nanus (A. nanus) is an eremophyte exhibiting remarkable tolerance to environmental stress and DREB proteins may contribute to its tolerance to water deficit and low-temperature stress. In the present study, an A. nanus DREB A5 group transcription factor gene, AnDREB5.1, was isolated and characterized in terms of structure and function in abiotic stress tolerance. AnDREB5.1 protein is distributed in the nucleus, possesses transactivation capacity, and is capable of binding to DRE core cis-acting element. The transcription of AnDREB5.1 was induced under osmotic and cold stress. Tobacco seedlings overexpressing AnDREB5.1 displayed higher tolerance to cold stress, osmotic stress, and oxidative stress compared to wild-type tobacco (WT). Under osmotic and cold stress, overexpression of AnDREB5.1 increased antioxidant enzyme activity in tobacco leaves, inhibiting excessive elevation of ROS levels. Transcriptome sequencing analysis showed that overexpression of AnDREB5.1 raised the tolerance of transgenic tobacco seedlings to abiotic stress by regulating multiple genes, including antioxidant enzymes, transcription factors, and stress-tolerant related functional genes like NtCOR413 and NtLEA14. This study provides new evidence for understanding the potential roles of the DREB A5 subgroup members in plants.


Asunto(s)
Respuesta al Choque por Frío , Fabaceae , Respuesta al Choque por Frío/genética , Antioxidantes , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Fabaceae/genética , Estrés Fisiológico/genética , Plantones/genética , Plantones/metabolismo , Nicotiana/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Frío
10.
Lipids Health Dis ; 23(1): 83, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509578

RESUMEN

OBJECTIVE: To enhance the detection, management and monitoring of Chinese children afflicted with sitosterolemia by examining the physical characteristics and genetic makeup of pediatric patients. METHODS: In this group, 26 children were diagnosed with sitosterolemia, 24 of whom underwent genetic analysis. Patient family medical history, physical symptoms, tests for liver function, lipid levels, standard blood tests, phytosterol levels, cardiac/carotid artery ultrasounds, fundus examinations, and treatment were collected. RESULTS: The majority (19, 73.1%) of the 26 patients exhibited xanthomas as the most prevalent manifestation. The second most common symptoms were joint pain (7, 26.9%) and stunted growth (4, 15.4%). Among the 24 (92.3%) patients whose genetics were analyzed, 16 (66.7%) harbored ABCG5 variants (type 2 sitosterolemia), and nearly one-third (8, 33.3%) harbored ABCG8 variants (type 1 sitosterolemia). Additionally, the most common pathogenic ABCG5 variant was c.1166G > A (p.Arg389His), which was found in 10 patients (66.7%). Further analysis did not indicate any significant differences in pathological traits among those carrying ABCG5 and ABCG8 variations (P > 0.05). Interestingly, there was a greater abundance of nonsense variations in ABCG5 than in ABCG8 (P = 0.09), and a greater frequency of splicing variations in ABCG8 than ABCG5 (P = 0.01). Following a change in diet or a combination of ezetimibe, the levels of cholesterol and low-density lipoprotein were markedly decreased compared to the levels reported before treatment. CONCLUSION: Sitosterolemia should be considered for individuals presenting with xanthomas and increased cholesterol levels. Phytosterol testing and genetic analysis are important for early detection. Managing one's diet and taking ezetimibe can well control blood lipids.


Asunto(s)
Hipercolesterolemia , Enfermedades Intestinales , Errores Innatos del Metabolismo Lipídico , Fitosteroles , Fitosteroles/efectos adversos , Xantomatosis , Humanos , Niño , Lipoproteínas/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 5/genética , Fitosteroles/genética , Colesterol , Ezetimiba/uso terapéutico
11.
Eur J Public Health ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38607985

RESUMEN

BACKGROUND: Since the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection exhibits multi-organ damage with diverse complications, the correlation between age, gender, medical history and clinical manifestations of novel coronavirus disease 2019 (COVID-19) patients was investigated. METHODS: 1640 patients who were infected with SARS-CoV-2 and hospitalized at the First Affiliated Hospital of Ningbo University from 22 December 2022 to 1 March 2023 were categorized and analysed. Normal distribution test and variance homogeneity test were performed. Based on the test results, one-way analysis of variance, Pearson's chi-squared test and logistic regression analysis were conducted in the study. RESULTS: According to the ANOVA, there was a significant difference in the age distribution (P = .001) between different clinical presentations, while gender did not (P = .06). And regression analysis showed that age, hypertension, atherosclerosis and cancer were significant hazard factors for the development of predominant clinical manifestations in patients hospitalized with novel COVID-19. Additionally, infection with SARS-CoV-2 has the potential to exacerbate the burden on specific diseased or related organs. CONCLUSION: The elderly who are infected with SARS-CoV-2 ought to be treated with emphasis not only on antiviral therapy but also on individualized treatment that takes their medical history and comorbidities into account.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38870503

RESUMEN

Objective: To investigate the clinical effects of new fiberoptic cholangioscopy-guided percutaneous transhepatic choledochoscope lithotomy (PTCSL) combined with dual-frequency laser lithotripsy for the treatment of intractable hepatolithiasis. Methods: Eighty patients with intractable hepatolithiasis who received treatment in the Second Hospital Affiliated to Zhejiang University School of Medicine from December 2020 to December 2022 were grouped according to the surgical methods. Forty-two patients who received hepatectomy were divided into the control group, 38 patients who received new fiber-optic choledochoscope-guided PTCSL combined with dual-frequency laser lithotripsy were divided into the observation group, and the treatment results of the two groups were compared. Results: The operation time, postoperative pain duration, and hospital stay of the observation group were significantly shorter than those of the control group, and intraoperative bleeding was significantly lower than that of the control group, with statistically significant differences (P < .05). Seven days after surgery, the total bilirubin (TBIL), alanine aminotransferase (ALT), and albumin (ALB) levels in the observation group were significantly lower than those in the control group (P < .05). The stone residual rate of 7.89% in the observation group was significantly lower than that of 26.19% in the control group (χ2=4.625, P < .05). The difference in biliary bleeding rate between the two groups was not statistically significant (χ2=0.427, P > .05). Conclusion: Overall results of new fiber-optic choledochoscope-guided PTCSL combined with dual-frequency laser lithotripsy for the treatment of intractable hepatolithiasis.

13.
Chem Biodivers ; 21(3): e202400017, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38321767

RESUMEN

Three undescribed isosteroidal alkaloids, przewalskines A-C (1-3), as well as seven known alkaloids (4-10) were obtained from Fritillaria przewalskii bulbs. Their structures were deduced by extensive HRESIMS, 1D NMR, and 2D NMR analyses, and their bioactivities were evaluated involving the anti-inflammatory and inhibitory potencies on AChE, BChE, and Aß aggregation. Compound 4 revealed the potent effect on inhibiting Aß aggregation activity with IC50 value of 33.1 µM, AChE activity with IC50 value of 6.9 µM, and also showed NO release inhibitory acitivity with IC50 value of 32.6 µM. These findings contribute new multi-.target anti-AD agents and embody the chemical diversity of F. przewalskii.


Asunto(s)
Alcaloides , Fritillaria , Fritillaria/química , Alcaloides/farmacología , Alcaloides/química
14.
Ann Plast Surg ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38896864

RESUMEN

BACKGROUND: The reliability and repeatability of stereophotogrammetry and CT in 3-dimensional anthropometric facial analysis were investigated in this study, which also explored the clinical application of supine CT. METHOD: In this study, 3D CT and 3dMD stereophotogrammetry were used on 20 healthy volunteers. The fitting distance between stereophotogrammetry and CT scans at landmark points was measured, along with facial feature measurements (Al-Al) face width (Go-Go, Zy-Zy, Ex-Ex), and hemi-face height (Sn-Gn). The intraclass correlation coefficient (ICC) was employed to assess interrater agreement and to verify the reliability of the measurement methods. Paired t-analysis was utilized for analyzing intramethod displacement. RESULTS: The alare, nasion, and pronasale points were found to be minimally influenced by different positions and are more recommended as landmark points for registration. CT demonstrated good interrater reliability on all indicators. In stereophotogrammetry, measurements for Go-Go and Zy-Zy displayed an interclass correlation coefficient (ICC) of less than 0.75. Significant differences between the 2 methods were observed for En-En, Ex-Ex, and Go-Go (P < 0.05). Specifically, CT analysis for Go-Go showed a measurement 2.34 mm larger than that obtained with the 3dMD method. CONCLUSION: Both CT and stereophotogrammetry were found to be reliable methods for evaluating facial soft tissue. It is speculated that Go-Go measurement is primarily influenced by factors such as different positions, facial expressions, and gravity. These variables should be carefully considered during the evaluation of the mandibular angle region.

15.
Ann Plast Surg ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38896854

RESUMEN

ABSTRACT: Rhinophyma leads to severe facial deformities and significant social pressure for patients. Patients often seek medical intervention due to cosmetic defects and functional impairments, such as nasal congestion and airway collapse. Currently, there are numerous treatment modalities for rhinophyma, each with distinct advantages and disadvantages, leading to a lack of consensus in nasal vegetation management. Severe thickening in the nasal area can obstruct breathing through external nasal valve blockage, necessitating appropriate management for relief. This article presents a case study involving severe rhinophyma with respiratory obstruction that was successfully treated using incomplete resection followed by reconstruction to restore normal nasal contour. This not only achieved an upright position for nasal columella but also improved nasal contour to achieve normal appearance levels while completely relieving respiratory tract obstruction and enhancing patients' ventilation function. This method is easily performed without requiring additional expensive equipment, making it economically feasible even in ordinary medical centers while enabling patients to achieve a high quality of life.

16.
Sensors (Basel) ; 24(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38339495

RESUMEN

Photoelectric smoke detectors are the most cost-effective devices for very early warning fire alarms. However, due to the different light intensity response values of different kinds of fire smoke and interference from interferential aerosols, they have a high false-alarm rate, which limits their popularity in Chinese homes. To address these issues, an embedded spatial-temporal convolutional neural network (EST-CNN) model is proposed for real fire smoke identification and aerosol (fire smoke and interferential aerosols) classification. The EST-CNN consists of three modules, including information fusion, scattering feature extraction, and aerosol classification. Moreover, a two-dimensional spatial-temporal scattering (2D-TS) matrix is designed to fuse the scattered light intensities in different channels and adjacent time slices, which is the output of the information fusion module and the input for the scattering feature extraction module. The EST-CNN is trained and tested with experimental data measured on an established fire test platform using the developed dual-wavelength dual-angle photoelectric smoke detector. The optimal network parameters were selected through extensive experiments, resulting in an average classification accuracy of 98.96% for different aerosols, with only 67 kB network parameters. The experimental results demonstrate the feasibility of installing the designed EST-CNN model directly in existing commercial photoelectric smoke detectors to realize aerosol classification.

17.
Sensors (Basel) ; 24(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38474960

RESUMEN

Emissions from thermal power plants have always been the central consideration for environmental protection. Existing optical sensors in thermal power plants usually measure the total mass concentration of the particulate matter (PM) by a single-wavelength laser, bearing intrinsic errors owing to the variation in particle size distribution (PSD). However, the total mass concentration alone cannot characterize all the harmful effects of the air pollution caused by the power plant. Therefore, it is necessary to measure the mass concentration and PSD simultaneously, based on which we can obtain multi-particle-size channel mass concentration. To achieve this, we designed an optical sensor based on the three-wavelength technique and tested its performance in a practical environment. Results showed that the prototype cannot only correctly measure the mass concentration of the emitted PM but also determine the mean diameter and standard deviation of the PSDs. Hence, the mass concentrations of PM10, PM2.5, and PM1 are calculated, and the air pollutants emission by a thermal power plant can be estimated comprehensively.

18.
Sensors (Basel) ; 24(6)2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38544041

RESUMEN

Infrared video target detection is a fundamental technology within infrared warning and tracking systems. In long-distance infrared remote sensing images, targets often manifest as circular spots or even single points. Due to the weak and similar characteristics of the target to the background noise, the intelligent detection of these targets is extremely complex. Existing deep learning-based methods are affected by the downsampling of image features by convolutional neural networks, causing the features of small targets to almost disappear. So, we propose a new infrared video weak-target detection network based on central point regression. We focus on suppressing the image background by fusing the different features between consecutive frames with the original image features to eliminate the background's influence. We also employ high-resolution feature preservation and incorporate a spatial-temporal attention module into the network to capture as many target features as possible and improve detection accuracy. Our method achieves superior results on the infrared image weak aircraft target detection dataset proposed by the National University of Defense Technology, as well as on the simulated dataset generated based on real-world observation. This demonstrates the efficiency of our approach for detecting weak point targets in infrared continuous images.

19.
Sensors (Basel) ; 24(10)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38793981

RESUMEN

Acoustic tomography utilizes sensor arrays to collect sound wave signals, enabling non-contact measurement of physical parameters within an area of interest. Compared to optical technologies, acoustic tomography offers the advantages of low cost, low maintenance, and easy installation. Current research in acoustic tomography mainly focuses on reconstruction algorithms for temperature fields, while monitoring the composition and concentration of gases is significant for ensuring safety and improving efficiency, such as in scenarios like boiler furnaces and aviation engine nozzles. In excitable gases, the speed of sound exhibits an S-shaped curve that changes with frequency, a characteristic that could be potentially useful for acoustic tomography. Therefore, this study primarily discusses the quantitative calculation of gas concentration and temperature based on the dispersion of the speed of sound. By employing graphic processing and pattern matching methods, a coupled relationship of the dispersion of the speed of sound with gas concentration and temperature is established. The projection intersection method is used to calculate the concentration and temperature of binary and ternary gas mixtures. Combined with the inversion method, a joint reconstruction method for gas concentration fields and temperature fields based on the dispersion of the speed of sound is developed. The feasibility of the proposed simultaneous reconstruction method for temperature and concentration fields is validated using numerical simulations. Additionally, an acoustic tomography experimental system was set up to conduct reconstruction experiments for binary gas concentration fields and temperature fields, confirming the effectiveness of the proposed method.

20.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1673-1682, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621951

RESUMEN

An evidence map was established to comprehensively sort out the clinical research in the treatment of post-acute myocardial infarction heart failure(P-AMI-HF) with Chinese patent medicines, so as to reveal the distribution of evidence in this field. CNKI, Wanfang, VIP, SinoMed, PubMed, Cochrane Library, and EMbase were searched for the randomized controlled trial(RCT), systematic reviews/Meta-analysis, and guidelines/consensus in this field. The evidence was analyzed and displayed in the form of a combination of text, charts, bubble charts, and bar charts, and the quality of RCT, systematic reviews/Meta-analysis, and guidelines/consensus were evaluated by RoB 1.0, AMSTAR2, and AGREE Ⅱ, respectively. A total of 163 RCTs, 4 systematic reviews/Meta-analysis, 1 network Meta-analysis, 2 observational studies, and 5 guidelines/consensus were included. In recent years, the total number of publications in this field has shown an upward trend. There were a variety of Chinese patent medicines in the treatment of P-AMI-HF, among which Shenfu Injection received the most attention. The clinical RCT and systematic reviews/Meta-analysis generally had poor quality, and the RCT mostly had a small size, a single center, and a short cycle. The outcome indicators mainly included cardiac function indicators, myocardial injury markers, total response rate, hemodynamic indicators, and safety indicators, while the characteristic efficacy indicators of TCM received insufficient attention. The development processes of some guidelines/consensus lack standardization, which compromised their authority and rationality. Chinese patent medicines have advantages in the treatment of P-AMI-HF, while there are also problems, which remain to be solved by more high-quality evidence. That is, more large-sample and multi-center clinical studies should be carried out in the future, and the formulation process of relevant systematic reviews/Meta-analysis and guideline/consensus should be standardized and the quality of evidence should be improved. In this way, the effectiveness and safety of Chinese patent medicines in the treatment of P-AMI-HF can be explored.


Asunto(s)
Medicamentos Herbarios Chinos , Insuficiencia Cardíaca , Medicina Tradicional de Asia Oriental , Infarto del Miocardio , Humanos , Medicamentos sin Prescripción/uso terapéutico , Medicamentos Herbarios Chinos/efectos adversos , Infarto del Miocardio/tratamiento farmacológico , Metaanálisis en Red , Insuficiencia Cardíaca/tratamiento farmacológico , Medicina Tradicional China , Ensayos Clínicos Controlados Aleatorios como Asunto
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