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1.
Adv Sci (Weinh) ; : e2401685, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664981

RESUMO

The redox mediated photoelectrochemical (PEC) or electrochemical (EC) alkene oxidation process is a promising method to produce high value-added epoxides. However, due to the competitive reaction of water oxidation and overoxidation of the mediator, the utilization of the electricity is far below the ideal value, where the loss of epoxidation's faradaic efficiency (FE) is ≈50%. In this study, a Br-/HOBr-mediated method is developed to achieve a near-quantitative selectivity and ≈100% FE of styrene oxide on α-Fe2O3, in which low concentration of Br- as mediator and locally generated acidic micro-environment work together to produce the higher active HOBr species. A variety of styrene derivatives are investigated with satisfied epoxidation performance. Based on the analysis of local pH-dependent epoxidation FE and products distribution, the study further verified that HOBr serves as the true active mediator to generate the bromohydrin intermediate. It is believed that this strategy can greatly overcome the limitation of epoxidation FE to enable future industrial applications.

3.
Chemosphere ; 355: 141834, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565376

RESUMO

Membrane fouling caused by the organics-coated particles was the main obstacle for the highly efficient shale gas produced water (SGPW) treatment and recycling. In this study, a novel hybrid electrocoagulation (EC) and E-peroxone process coupled with UF (ECP-UF) process was proposed to examine the efficacy and elucidate the mechanism for UF fouling mitigation in assisting SGPW reuse. Compared to the TMP (transmembrane pressure) increase of -15 kPa in the EC-UF process, TMP in ECP-UF system marginally increased to -1.4 kPa for 3 filtration cycles under the current density of 15 mA/cm2. Both the total fouling index and hydraulically irreversible fouling index of the ECP-UF process were significantly lower than those of EC-UF process. According to the extended Derjaguin-Landau-Verwey-Overbeek theory, the potential barriers was the highest for ECP-UF processes due to the substantial increase of the acid-base interaction energy in ECP-UF process, which was well consistent with the TMP and SEM results. Turbidity and TOC of ECP-UF process were 63.6% and 45.8% lower than those of EC-UF process, respectively. According to the MW distribution, the variations of compounds and their relative contents were probably due to the oxidation and decomposing products of the macromolecular organics. The number of aromatic compound decreased, while the number of open-chain compounds (i.e., alkenes, alkanes and alcohols) increased in the permeate of ECP-UF process. Notably, the substantial decrease in the relative abundance of di-phthalate compounds was attributed to the high reactivity of these compounds with ·OH. Mechanism study indicated that ECP could realize the simultaneous coagulation, H2O2 generation and activation by O3, facilitating the enhancement of ·OH and Alb production and therefore beneficial for the improved water quality and UF fouling mitigation. Therefore, the ECP-UF process emerges as a high-efficient and space-saving approach, yielding a synergistic effect in mitigating UF fouling for SGPW recycling.


Assuntos
Ultrafiltração , Purificação da Água , Gás Natural , Peróxido de Hidrogênio , Membranas Artificiais , Purificação da Água/métodos , Eletrocoagulação
4.
Artigo em Inglês | MEDLINE | ID: mdl-38564349

RESUMO

Texture synthesis is a fundamental problem in computer graphics that would benefit various applications. Existing methods are effective in handling 2D image textures. In contrast, many real-world textures contain meso-structure in the 3D geometry space, such as grass, leaves, and fabrics, which cannot be effectively modeled using only 2D image textures. We propose a novel texture synthesis method with Neural Radiance Fields (NeRF) to capture and synthesize textures from given multi-view images. In the proposed NeRF texture representation, a scene with fine geometric details is disentangled into the meso-structure textures and the underlying base shape. This allows textures with meso-structure to be effectively learned as latent features situated on the base shape, which are fed into a NeRF decoder trained simultaneously to represent the rich view-dependent appearance. Using this implicit representation, we can synthesize NeRF-based textures through patch matching of latent features. However, inconsistencies between the metrics of the reconstructed content space and the latent feature space may compromise the synthesis quality. To enhance matching performance, we further regularize the distribution of latent features by incorporating a clustering constraint. In addition to generating NeRF textures over a planar domain, our method can also synthesize NeRF textures over curved surfaces, which are practically useful. Experimental results and evaluations demonstrate the effectiveness of our approach.

5.
Environ Pollut ; 349: 123921, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38574948

RESUMO

The surface functional groups of hydrochar are crucial to its surface properties, and their contents are strongly positively correlated with the adsorption performance. In this study, acrylate-functionalized hydrochar (AHC) with varying contents of O-containing functional groups (OFGs) was synthesized via hydrothermal carbonization (HTC) of bamboo, acrylic acid and an initiator, and then deprotonated with NaOH. The AHCs were analyzed by various characterization techniques. During HTC, the higher amount of acrylic acid added led to higher carbon, oxygen and carboxyl contents, and to the larger specific surface area and pore volume of AHC. The adsorption kinetics, isotherms, thermodynamic, ionic strength and pH effects of Pb(II) on AHC were studied. Adsorption isotherms and kinetics obeyed Langmuir and pseudo-second-order models, respectively, indicating adsorption is monolayer chemical process. The adsorptive ability was well linearly related to the OFG contents of AHC. When acrylic acid was added to 25 mL during HTC, the adsorbing ability of AHC over Pb(II) reached 193.90 mg g-1. Hence, direct HTC of acrylic acid, biomass and an initiator can prepare hydrochar with controllable OFG contents, which is a prospective adsorbent for treating metal cations.

6.
Opt Lett ; 49(7): 1812-1815, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560871

RESUMO

To concurrently determine the thermophysical parameters of semi-transparent materials, a novel, to the best of our knowledge, integrated approach for concurrent measurement is proposed. In the measurement setup, a high-temperature radiation source and a beam reducer are employed to minimize the influence of background radiation. In order to differentiate between the transmitted and emitted radiation in the detection signal, the radiation signals from the radiation source are measured under four different conditions, enabling the calculation of transmissivity, emissivity, and reflectivity. The reliability and accuracy of the measurement method are validated by the thermophysical parameters of sapphire, and the results demonstrate a strong agreement between the measured data and previous findings. The combined uncertainties of transmissivity and emissivity for the sapphire at 753 K are estimated, highlighting the novel contribution of this method in investigating the thermophysical parameters of semi-transparent materials.

7.
Phys Rev E ; 109(3-2): 035303, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38632759

RESUMO

Real-world water wave fields exhibit significant nonlinear and nonisospectral characteristics, making it challenging to predict their evolution by relying solely on numerical simulation or exact solutions using integrable system theory. Hence, this paper introduces a fast and adaptive method of modal identification and prediction in nonisospectral water wave fields using the reduced-order nonlinear solution (RONS) scheme. Specifically, we discuss the coarse graining and mode extraction of wave field snapshots from the data-driven and physics-driven perspectives and utilize the RONS method for principle modal prediction of nonisospectral water wave fields. This is achieved by investigating the standard and nonisospectral Gardner system describing nonlinear water waves as a demonstration. Through detailed comparison and analysis, the fundamental solitary behaviors and dispersive effects in the Gardner system are discussed. Subsequently, a neighbor approximation is developed that combines the essences of symbolic precomputation and numerical computation in the RONS procedure, which exploits the locality of nonlinear interactions in water wave fields.

8.
BMC Med ; 22(1): 153, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609953

RESUMO

BACKGROUND: Prediction of lymph node metastasis (LNM) is critical for individualized management of papillary thyroid carcinoma (PTC) patients to avoid unnecessary overtreatment as well as undesired under-treatment. Artificial intelligence (AI) trained by thyroid ultrasound (US) may improve prediction performance. METHODS: From September 2017 to December 2018, patients with suspicious PTC from the first medical center of the Chinese PLA general hospital were retrospectively enrolled to pre-train the multi-scale, multi-frame, and dual-direction deep learning (MMD-DL) model. From January 2019 to July 2021, PTC patients from four different centers were prospectively enrolled to fine-tune and independently validate MMD-DL. Its diagnostic performance and auxiliary effect on radiologists were analyzed in terms of receiver operating characteristic (ROC) curves, areas under the ROC curve (AUC), accuracy, sensitivity, and specificity. RESULTS: In total, 488 PTC patients were enrolled in the pre-training cohort, and 218 PTC patients were included for model fine-tuning (n = 109), internal test (n = 39), and external validation (n = 70). Diagnostic performances of MMD-DL achieved AUCs of 0.85 (95% CI: 0.73, 0.97) and 0.81 (95% CI: 0.73, 0.89) in the test and validation cohorts, respectively, and US radiologists significantly improved their average diagnostic accuracy (57% vs. 60%, P = 0.001) and sensitivity (62% vs. 65%, P < 0.001) by using the AI model for assistance. CONCLUSIONS: The AI model using US videos can provide accurate and reproducible prediction of cervical lymph node metastasis in papillary thyroid carcinoma patients preoperatively, and it can be used as an effective assisting tool to improve diagnostic performance of US radiologists. TRIAL REGISTRATION: We registered on the Chinese Clinical Trial Registry website with the number ChiCTR1900025592.


Assuntos
Inteligência Artificial , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico por imagem
9.
Plant Dis ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598853

RESUMO

The cultivated aromatic medicinal herb Atractylodes lancea (Thunb.) DC. is widely used in the pharmaceuticals, nutraceuticals, and cosmetics industries (Na-Bangchang et al. 2014; Zhan et al. 2023). Huanggang in Hubei Province is a major production area for A. lancea (Huang et al. 2022; Wang et al. 2023). In April 2023, more than two-thirds of the surveyed plant leaves in this region exhibited virus-like symptoms, such as curling and mosaic patterns. To identify the underlying cause, 80 symptomatic plant leaf samples were collected from four fields (20 leaves per field) in this region and pooled for virome analysis. Total RNA, including ribosomal RNA, was extracted from the pooled samples using the Plant RNA Extraction Mini Kit (Onrew Biotech, Guangdong, China), for sequencing library construction. The Illumina NovaSeq 6000 platform was used to sequence the library and generate 150 bp paired-end reads. After processing the raw data with Trimmomatic software, a total of 44,354,650 high-quality clean reads were obtained. The clean reads were aligned against ribosomal RNA using BWA software (v0.7.17) to avoid interference and eliminate corresponding sequences. After removing potential contamination, contig assembly of the clean reads was performed using Megahit software (v1.2.9). The resulting contigs were compared with the virus NT database using the BLASTn program. Sequence pairwise comparison revealed 8 contigs (574 nt to 2243 nt) with identities ranging from 81.88% to 90.77% with Atractylodes mild mottle virus (AMMV, NC_027924.1, Lim et al., 2015). Additionally, contigs mapped to Carlavirus, Pelarspovirus, and other plant viruses in our virome dataset had low coverage and pairwise identity (less than 70%), which need to be further investigated. The presence of AMMV was confirmed by aligning the clean reads to the reference sequence (NC_027924.1) using BWA and SAMtools software, resulting in a consensus sequence (8024 nt) with gaps. DNA extraction from the pooled samples was performed using the Rapid Universal Genomic DNA Extraction Kit (Simgen, Zhejiang, China). Two pairs of specific primers, 3399F (5'-AAAGAAGAACCTCCTGATACGG-3')/5924R (5'-TGAACCTGATTCTCTTGGC-3') and 1830F (5'- CTCAGGAAATCCCAATGC -3')/3640R(5'-TTTCCCAATGTTCTTCGGG-3'), were designed to amplify the complete gene sequences of polymerase and coat protein (CP), based on the consensus sequence. The PCR products with the lengths of 2521 bp and 1814 bp were cloned into the pMD18-T vector (Takara Biotech, Dalian, China) for sequencing. The BLASTn analysis showed that the polymerase and CP gene sequences shared an identity of 94.51% (1929/2041 nt) and 88.41% (1419/1605 nt) with the AMMV isolate (NC_027924.1), respectively. The sequences have been deposited in GenBank under the accession numbers OR544810 and OR544811. We collected leaves from 32 A. lancea plants (16 symptomatic and 16 asymptomatic) in the fields. RT-PCR was conducted using CPF (5'-CTGCGAATATGAAAGTGC-3') and CPR (5'-GGTGAGCTTGTCTGTTAGG-3') primers, which were designed targeting a 527bp fragment of the CP gene (OR544811). Amplicons of the expected size (527bp) were detected in 24 plants (11 symptomatic and 13 asymptomatic), three of which were sequenced by Sanger sequencing, showing a 100% match to OR544811. These findings indicate that AMMV is prevalent in the major production area of A. lancea. Further research is needed to better characterize the potential risks of AMMV to A. lancea cultivation in China as well as other countries.

10.
Angew Chem Int Ed Engl ; : e202400441, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587149

RESUMO

Nickel-catalyzed transannulation reactions triggered by the extrusion of small gaseous molecules have emerged as a powerful strategy for the efficient construction of heterocyclic compounds. However, it's asymmetric synthesis remains challenging because of the difficulty in controlling stereo- and regioselectivity. Herein, we report the first nickel-catalyzed asymmetric synthesis of N-N atropisomers by the denitrogenative transannulation of benzotriazones with internal alkynes. A broad range of N-N atropisomers was obtained with excellent regio- and enantioselectivity under mild conditions. Moreover, density functional theory (DFT) calculations provided insights into the nickel-catalyzed reaction mechanism and enantioselectivity control.

11.
J Chromatogr A ; 1721: 464861, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38564931

RESUMO

The covalent attachment of polyoxometalates (POMs) to polymers has been developed as a strategic approach for the advancement of POM-based hybrid materials with versatile applications. In this study, we utilized thiol-maleimide Michael addition to investigate the kinetics and efficacy of the "one-to-one" conjugation between Keggin type POM and polystyrene. We explored the effects of solvent polarity, catalyst, molecular weight of PS and synthetic strategies on the reaction kinetics and efficiency, by means of reverse-phase high-performance liquid chromatography (RP-HPLC). A series of comparative analysis affirmed the superior efficiency of the one-pot method, particularly when facilitated by the addition of a high-polarity solvent and an excess of maleimide. These findings offer valuable insights into the intricate interplay between reaction conditions, kinetics, and selectivity in thiol-maleimide reactions of POMs and polymers. They hold profound implications for advancing the study of POM-based multifunctional materials and the synthesis of complex hybrid molecules.


Assuntos
Ânions , Polieletrólitos , Polímeros , Compostos de Sulfidrila , Polímeros/química , Maleimidas/química , Solventes
12.
Molecules ; 29(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38542970

RESUMO

Currently, little is known about the characteristics of polyphenol oxidase from wheat bran, which is closely linked to the browning of wheat product. The wheat PPO was purified by ammonium sulfate precipitation, DEAE-Sepharose ion-exchange column, and Superdex G-75 chromatography column. Purified wheat PPO activity was 11.05-fold higher, its specific activity was 1365.12 U/mg, and its yield was 8.46%. SDS-PAGE showed that the molecular weight of wheat PPO was approximately 21 kDa. Its optimal pH and temperature were 6.5 and 35 °C for catechol as substrate, respectively. Twelve phenolic substrates from wheat and green tea were used for analyzing the substrate specificity. Wheat PPO showed the highest affinity to catechol due to its maximum Vmax (517.55 U·mL-1·min-1) and low Km (6.36 mM) values. Docking analysis revealed strong affinities between catechol, gallic acid, EGCG, and EC with binding energies of -5.28 kcal/mol, -4.65 kcal/mol, -4.21 kcal/mol, and -5.62 kcal/mol, respectively, for PPO. Sodium sulfite, ascorbic acid, and sodium bisulfite dramatically inhibited wheat PPO activity. Cu2+ and Ca2+ at 10 mM were considered potent activators and inhibitors for wheat PPO, respectively. This report provides a theoretical basis for controlling the enzymatic browning of wheat products fortified with green tea.


Assuntos
Catecol Oxidase , Fibras na Dieta , Catecol Oxidase/química , Fibras na Dieta/análise , Concentração de Íons de Hidrogênio , Cinética , Proteínas de Plantas/metabolismo , Catecóis/análise , Especificidade por Substrato , Chá
13.
Chem Sci ; 15(10): 3446-3452, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38455027

RESUMO

Electrocatalytic hydrogenation (ECH) enables the sustainable production of chemicals under ambient conditions, in which catalysts catering for the different chemisorption of reactants/intermediates are desired but still challenging. Here, Mo2C@MoS2 heteronanorods with dual active-sites are developed to accomplish efficient nitroarene ECH according to our theoretical prediction that the binding of atomic H and nitro substrates would be synergistically strengthened on Mo2C-MoS2 interfaces. They afford high faradaic efficiency (>85%), yield (>78%) and selectivity (>99%) for the reduction of 4-nitrostyrene (4-NS) to 4-vinylaniline (4-VA) in neutral electrolytes, outperforming not only the single-component counterparts of Mo2C nanorods and MoS2 nanosheets, but also recently reported noble-metals. Accordingly, in situ Raman spectroscopy combined with electrochemical tests clarifies the rapid ECH of 4-NS on Mo2C-MoS2 interfaces due to the facilitated elementary steps, quickly refreshing active sites for continuous electrocatalysis. Mo2C@MoS2 further confirms efficient and selective ECH toward functional anilines with other well-retained reducible groups in wide substrate scope, underscoring the promise of dual-site engineering for exploring catalysts.

14.
Phys Rev Lett ; 132(8): 083601, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457704

RESUMO

Quantum non-Gaussianity, a more potent and highly useful form of nonclassicality, excludes all convex mixtures of Gaussian states and Gaussian parametric processes generating them. Here, for the first time, we conclusively test quantum non-Gaussian coincidences of entangled photon pairs with the Clauser-Horne-Shimony-Holt-Bell factor S=2.328±0.004 from a single quantum dot with a depth up to 0.94±0.02 dB. Such deterministically generated photon pairs fundamentally overcome parametric processes by reducing crucial multiphoton errors. For the quantum non-Gaussian depth of the unheralded (heralded) single-photon state, we achieve the value of 8.08±0.05 dB (19.06±0.29 dB). Our Letter experimentally certifies the exclusive quantum non-Gaussianity properties highly relevant for optical sensing, communication, and computation.

15.
Front Plant Sci ; 15: 1332443, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38504896

RESUMO

Introduction: Salvia L., representing the largest genus within the mint family, is noted for its global distribution of approximately 1000 species, with East Asia, and particularly China, recognized as a critical center of diversity for the genus. Methods: Our research was conducted through extensive fieldwork in Guidong County, Hunan Province, China, where we identified a previously undescribed species of Salvia. The identification process involved detailed morphological observations, phylogenetic analyses, and plastid genomics. Results: The newly discovered species, Salvia guidongensis, exhibits unique characteristics not commonly observed in the East Asian lineage of Salvia, including dual floral colors within natural populations-either pale purple or pale yellow. Morphologically, while it shares similarities with members of sect. Glutinaria, S. guidongensis is distinct in its floral morphology, stature, and specific foliar traits. Phylogenetic analysis places S. guidongensis in a unique clade within the East Asian lineage of Salvia, suggesting it may serve as an important evolutionary link. Additionally, we explored the plastome features of S. guidongensis, comparing them with those of closely related species. Discussion: The discovery of S. guidongensis not only entriches the taxonomic tapestry of Salvia but also provides critical insights into the biogeography and evolutionary pathways of the genus in East Asia. By integrating morphological and molecular data, we validate the novel status of S. guidongensis and highlight its significance in bridging taxonomic and evolutionary gaps within Sect. Glutinaria of Salvia.

16.
Sci Rep ; 14(1): 6331, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491005

RESUMO

In this study we aimed to investigate the prevalence of SARS-CoV-2 infection in psoriasis patients, and outcomes of SARS-CoV-2 infection and associated risk factors. A cross-sectional survey was conducted from February 2023 to March 2023. Information was obtained with online questionnaire about psoriasis patients on demographic characteristics, clinical characteristics, SARS-CoV-2 infection and outcomes, vaccination, and routine protection against COVID-19. Logistic regression analysis was used to explore risk factors with SARS-CoV-2 infection and exacerbation of psoriasis. A total of 613 participants were recruited. 516 (84.2%) were infected, and associated factors were sex, working status, routine protection against COVID-19, COVID-19 vaccination, impaired nail, infection exacerbate psoriasis, and severity of psoriasis. Among the patients infected with SARS-CoV-2, 30 (5.8%) required hospitalization, 122 (23.6%) had psoriasis exacerbation due to SARS-CoV-2 infection, and associated factors were subtype of psoriasis, discontinuation of psoriasis treatment during SARS-CoV-2 infection, response following COVID-19 vaccination, and severity of psoriasis. Booster dose vaccination contributed a low probability of COVID-19 sequelae. COVID-19 vaccine's effectiveness was unsatisfactory, while booster dose vaccination reduced the occurrence of COVID-19 sequelae in psoriasis patients of Southwest China. Patients treated with psoriasis shown to be safe, without a higher incidence of SARS-CoV-2 infection or COVID-19hospitalization compared to untreated patients. Stopping treatment during SARS-CoV-2 infection led to psoriasis exacerbation, so psoriasis treatment could be continued except severe adverse reaction.


Assuntos
COVID-19 , Psoríase , Humanos , COVID-19/epidemiologia , Estudos Transversais , Prevalência , SARS-CoV-2 , Vacinas contra COVID-19 , China/epidemiologia , Progressão da Doença , Psoríase/complicações , Psoríase/epidemiologia
17.
Carbohydr Polym ; 334: 122058, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553243

RESUMO

Global public health is seriously threatened by thrombotic disorders because of their high rates of mortality and disability. Most thrombolytic agents, especially protein-based pharmaceuticals, have a short half-life in circulation, reducing their effectiveness in thrombolysis. The creation of an intelligent drug delivery system that delivers medication precisely and releases it under regulated conditions at nearby thrombus sites is essential for effective thrombolysis. In this article, we present a unique medication delivery system (MCRUA) that selectively targets platelets and releases drugs by stimulation from the thrombus' microenvironment. The thrombolytic enzyme urokinase-type plasminogen-activator (uPA) and the anti-inflammatory medication Aspirin (acetylsalicylic acid, ASA) are both loaded onto pH-sensitive CaCO3/cyclodextrin crosslinking metal-organic frameworks (MC) that make up the MCRUA system. c(RGD) is functionalized on the surface of MC, which is functionalized by RGD to an esterification reaction. Additionally, the thrombus site's acidic microenvironment causes MCRUA to disintegrate to release uPA for thrombolysis and aiding in vessel recanalization. Moreover, cyclodextrin-encapsulated ASA enables the treatment of the inflammatory environment within the thrombus, enhancing the antiplatelet aggregation effects and promoting cooperative thrombolysis therapy. When used for thrombotic disorders, our drug delivery system (MCRUA) promotes thrombolysis, suppresses rethrombosis, and enhances biosafety with fewer hemorrhagic side effects.


Assuntos
Ciclodextrinas , Estruturas Metalorgânicas , Trombose , Humanos , Terapia Trombolítica , Ciclodextrinas/uso terapêutico , Fibrinolíticos/farmacologia , Fibrinolíticos/uso terapêutico , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Trombose/tratamento farmacológico , Aspirina/farmacologia , Oligopeptídeos
18.
Artigo em Inglês | MEDLINE | ID: mdl-38426379

RESUMO

OBJECTIVES: Preoperative identification of different stromal subtypes of pleomorphic adenoma (PA) of the salivary gland is crucial for making treatment decisions. We aimed to developed and validated a model based on histogram analysis (HA) of ultrasound (US) images for predicting tumor stroma ratio (TSR) in SPA. METHODS: A total of 219 PA patients were divided into low-TSR (stroma-low) and high-TSR (stroma-high) groups, and enrolled in a training cohort (n = 151) and a validation cohort (n = 68). The least absolute shrinkage and selection operator regression algorithm was used to screen the most optimal clinical, US, and HA features. The selected features were entered into multivariable logistic regression analyses for further selection of independent predictors. Different models, including the nomogram model, the clinic-US (Clin + US) model, and the HA model, were built based on independent predictors using logistic regression. The performance levels of the models were evaluated and validated on the training and validation cohorts. RESULTS: Lesion size, shape, cystic areas, vascularity, HA_mean, and HA_skewness were identified as independent predictors for constructing the nomogram model. The nomogram model incorporating the clinical, US, and HA features achieved AUCs of 0.839 and 0.852 in the training and validation cohorts, respectively, demonstrating good predictive performance and calibration. Decision curve analysis and clinical impact curves further confirmed its clinical usefulness. CONCLUSIONS: The nomogram model we developed offers a practical tool for preoperative TSR prediction in PA, potentially enhancing clinical decision-making.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38416616

RESUMO

Most of the existing 3D talking face synthesis methods suffer from the lack of detailed facial expressions and realistic head poses, resulting in unsatisfactory experiences for users. In this paper, we propose a novel pose-aware 3D talking face synthesis method with a novel geometry-guided audio-vertices attention. To capture more detailed expression, such as the subtle nuances of mouth shape and eye movement, we propose to build hierarchical audio features including a global attribute feature and a series of vertex-wise local latent movement features. Then, in order to fully exploit the topology of facial models, we further propose a novel geometry-guided audio-vertices attention module to predict the displacement of each vertex by using vertex connectivity relations to take full advantage of the corresponding hierarchical audio features. Finally, to accomplish pose-aware animation, we expand the existing database with an additional pose attribute, and a novel pose estimation module is proposed by paying attention to the whole head model. Numerical experiments demonstrate the effectiveness of the proposed method on realistic expression and head movements against state-of-the-art methods.

20.
Opt Express ; 32(2): 1342-1356, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297689

RESUMO

This study presents a fast and accurate data processing method for multispectral radiation thermometry that can accurately measure the true temperature of steel materials without requiring a priori emissivity model. The method generates a temperature matrix by inputting emissivity values at different wavelengths and selects a reference vector from the matrix. Then, it rearranges the temperature matrices at other wavelengths and calculates the Euclidean distance between each column element of the rearranged matrix and the reference vector. The method uses an unconstrained optimization technique to minimize the Euclidean distance and obtain the true temperature and emissivity of the object simultaneously. We evaluate the performance of the method by simulation and experiment in the response band of 1.4 ∼ 2.5 µm and temperature range of 873 ∼ 1173 K. The simulation results indicate that the relative error of the inverted temperature is within 0.229%, and the average computation time is less than 112.301 ms. The experimental results show that the maximum temperature error during the measurement process is 0.813%. Our method provides a feasible and efficient solution for real-time temperature measurement of steel materials.

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