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1.
Med Eng Phys ; 124: 104101, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38418029

RESUMO

With the advancement of deep learning technology, computer-aided diagnosis (CAD) is playing an increasing role in the field of medical diagnosis. In particular, the emergence of Transformer-based models has led to a wider application of computer vision technology in the field of medical image processing. In the diagnosis of thyroid diseases, the diagnosis of benign and malignant thyroid nodules based on the TI-RADS classification is greatly influenced by the subjective judgment of ultrasonographers, and at the same time, it also brings an extremely heavy workload to ultrasonographers. To address this, we propose Swin-Residual Transformer (SRT) in this paper, which incorporates residual blocks and triplet loss into Swin Transformer (SwinT). It improves the sensitivity to global and localized features of thyroid nodules and better distinguishes small feature differences. In our exploratory experiments, SRT model achieves an accuracy of 0.8832 with an AUC of 0.8660, outperforming state-of-the-art convolutional neural network (CNN) and Transformer models. Also, ablation experiments have demonstrated the improved performance in the thyroid nodule classification task after introducing residual blocks and triple loss. These results validate the potential of the proposed SRT model to improve the diagnosis of thyroid nodules' ultrasound images. It also provides a feasible guarantee to avoid excessive puncture sampling of thyroid nodules in future clinical diagnosis.


Assuntos
Recuperação Demorada da Anestesia , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Ultrassonografia , Diagnóstico por Computador/métodos
2.
Materials (Basel) ; 16(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37570076

RESUMO

Molecular dynamics is a method of studying microstructure and properties by calculating and simulating the movement and interaction of molecules. The molecular dynamics simulation method has become an important method for studying the structural and dynamic characteristics of slag systems and can make up for the shortcomings of existing detection methods and experiments. Firstly, this paper analyzes the development process and application fields of molecular dynamics, summarizes the general simulation steps and software algorithms of molecular dynamics simulation methods, and discusses the advantages and disadvantages of the algorithms and the common functions of the software. Secondly, the research status and application progress of molecular dynamics simulation methods in the study of phosphate, silicate, aluminate and aluminosilicate are introduced. On this basis, a method of combining molecular dynamics simulation with laboratory experiments is proposed, which will help obtain more accurate simulation results. This review provides theoretical guidance and a technical framework for the effective analysis of the microstructure of different slag systems via molecular dynamics, so as to finally meet the needs of iron and steel enterprises in producing high-quality steel grades.

3.
Phys Med Biol ; 68(16)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37437581

RESUMO

Objective.Deep learning has demonstrated its versatility in the medical field, particularly in medical image segmentation, image classification, and other forms of automated diagnostics. The clinical diagnosis of thyroid nodules requires radiologists to locate nodules, diagnose conditions based on nodule boundaries, textures and their experience. This task is labor-intensive and tiring; therefore, an automated system for accurate thyroid nodule segmentation is essential. In this study, a model named DPAM-PSPNet was proposed, which automatically segments nodules in thyroid ultrasound images and enables to segment malignant nodules precisely.Approach.In this paper, accurate segmentation of nodule edges is achieved by introducing the dual path attention mechanism (DPAM) in PSPNet. In one channel, it captures global information with a lightweight cross-channel interaction mechanism. In other channel, it focus on nodal margins and surrounding information through the residual bridge network. We also updated the integrated loss function to accommodate the DPAM-PSPNet.Main results.The DPAM-PSPNet was tested against the classical segmentation model. Ablation experiments were designed for the two-path attention mechanism and the new loss function, and generalization experiments were designed on the public dataset. Our experimental results demonstrate that DPAM-PSPNet outperforms other existing methods in various evaluation metrics. In the model comparison experiments, it achieved performance with an mIOU of 0.8675, mPA of 0.9357, mPrecision of 0.9202, and Dice coefficient of 0.9213.Significance.The DPAM-PSPNet model can segment thyroid nodules in ultrasound images with little training data and generate accurate boundary regions for these nodules.

4.
Materials (Basel) ; 16(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36984385

RESUMO

High-nitrogen stainless steels are widely used due to their excellent comprehensive performance. In this study, the effects of process parameters (laser power, scanning speed, and cavity pressure) on the formation of high-nitrogen stainless steels were studied by using conventional selective laser melting and high-pressure selective laser melting (HPSLM). The nitrogen content, nitrogen emission, phase composition, microstructure, and microhardness of the high-nitrogen stainless steel samples obtained through selective laser melting (SLM) were analysed by using an oxygen/nitrogen/hydrogen analyser, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. The results showed that the maximum nitrogen emission in the SLM sample was 0.175 wt.%, the emission rate reached up to 54.7%, and the maximum nitrogen content in the HPSLM sample was 1.07 wt.%. There was no significant difference between the phase peak positions of the SLM samples with different laser powers and the original powder. The main phase of the HPSLM sample changed at 0.3 MPa (from α-Fe to γ-Fe phase); the microstructure of the SLM sample was mainly composed of columnar and cellular crystals, and columnar crystal bands formed along the direction of heat flow. The HPSLM sample was mainly composed of equiaxed crystals with a grain size of 10-15 µm. At an energy density of 136 J/mm3, the microhardness and relative density reached their peak values of 409 HV and 98.85%, respectively.

5.
Materials (Basel) ; 15(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499883

RESUMO

High-temperature annealing is a key step for the secondary recrystallization of grain-oriented silicon steel, which has an important effect on the final sharp Goss texture. In this work, the effects of three different annealing atmospheres during high-temperature annealing (100%H2, 25%N2 + 75%H2 and 50%N2 + 50%H2) on the secondary recrystallization microstructure and texture of Fe-3.2%Si-0.055%Nb low temperature grain-oriented silicon steel were analyzed by optical microscopy (OM) and electron back-scattered diffraction (EBSD) techniques, and the magnetic properties of the samples were compared. The results show that when the high-temperature annealing atmosphere is 100%H2, the texture of the grains with secondary recrystallization is mainly <110>//ND orientation, but the grains without secondary recrystallization have a disordered orientation. When the high-temperature annealing atmosphere is 50%H2 + 50%N2, the secondary recrystallization grains present a Goss texture and brass texture. After high-temperature annealing in the 25%N2 + 75%H2 atmosphere, the sample can be fully recrystallized to obtain secondary recrystallization grains; the grain size is relatively uniform and the texture is mainly a Goss texture with a sharp edge. The content of this reaches 93.1%, the magnetic induction B800 is the highest, reaching 1.89 T, and the iron loss P1.7/50 is the lowest, reaching 1.33 W/kg.

6.
Molecules ; 27(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36234989

RESUMO

Herein, a 3D hierarchical structure is constructed by growing NiCo2O4 nanowires on few-layer Ti3C2 nanosheets using Ni foam (NF) as substrate via simple vacuum filtration and solvothermal treatment. Ti3C2 nanosheets are directly anchored on NF surface without binders or surfactants, and NiCo2O4 nanowires composed of about 15 nm nanoparticles uniformly grow on Ti3C2/NF skeleton, which can provide abundant active sites and ion diffusion pathways for enhancing electrochemical performance. Benefiting from the unique structure feature and the synergistic effects of active materials, NiCo2O4/Ti3C2 exhibits a high specific capacitance of 2468 F g-1 at a current density of 0.5 A g-1 and a good rate performance. Based on this, an asymmetric supercapacitor (ASC) based on NiCo2O4/Ti3C2 as positive electrode and activated carbon (AC)/NF as negative electrode is assembled. The ASC achieves a high specific capacitance of 253 F g-1 at 1 A g-1 along with 91.5% retention over 10,000 cycles at 15 A g-1. Furthermore, the ACS presents an outstanding energy density of 90 Wh kg-1 at the power density of 2880 W kg-1. This work provides promising guidance for the fabrication of binder-free, free-standing and hierarchical composites for energy storage application.

7.
Front Chem ; 10: 943055, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873046

RESUMO

The superhydrophobic coatings with excellent performance are prepared on the brass substrate to improve its application limitations in real production. In this article, the superhydrophobicity was obtained by the modification of TiO2 nanoparticles, and the FAS/STA-TiO2 superhydrophobic coating of the composite structure was obtained by modification of 1, 1, 2H, 2H-perfluoroquine trimethyl silane (FAS). By using scanning electron microscopes (SEMs), X-ray spectrometers (EDSs), and Fourier transform infrared (FTIR) spectrometers, the surface morphology, chemical composition, and functional group structure of the samples were analyzed in turn. Experiments show that the water contact angle of the FAS-modified STA-TiO2 coating reaches 161.3°, and the sliding angle is close to 1.2°. Based on the chalk dust containment, it has enabled noticeable self-cleaning properties. The composite superhydrophobic coating also presents enhanced adhesive strength compared with the single coating by the tape peeling experiment. Moreover, the composite coating has a corrosion current density as low as 8.41 × 10-7 A/cm2, and the largest |Z| in low frequency in a 3.5% NaCl solution to achieve better protection of the brass substrate. It is also not difficult to see that FAS/STA-TiO2 coating can not only improve the corrosion resistance of brass substrates but also be applied to other metal substrates.

8.
ACS Omega ; 6(39): 25506-25517, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34632208

RESUMO

Phenol is a nocuous water pollutant that threatens human health and the ecological environment. CoOx-doped micron-sized hollow MgO rods were prepared for the treatment of phenol wastewater by catalytic ozonation. Magnesium sources, precipitants, initial precursor concentration, Co/Mg molar ratio, and catalyst calcination temperature were optimized to obtain the best catalysts. Prepared catalysts were also well characterized by various methods to analyze their structure and physical and chemical properties. In this process, CoOx/MgO with the largest large surface area (151.3 m3/g) showed the best catalytic performance (100 and 79.8% of phenol and chemical oxygen demand (COD) removal ratio, respectively). The hydrolysis of CoOx/MgO plays a positive role in the degradation of phenol. The catalytic mechanism of the degradation of O3 to free radicals over catalysts has been investigated by in situ electronic paramagnetic resonance (EPR). The catalyst can be reused at least five times without any activity decline. The prepared CoOx/MgO catalyst also showed excellent catalytic performance for removal and degradation of ciprofloxacin, norfloxacin, and salicylic acid.

9.
J Hazard Mater ; 377: 17-23, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31132677

RESUMO

UV photo-preactivation/thermally-induced grafting was employed for grafting 4-vinylpyridine (4-VP) on polyvinylidene fluoride (PVDF), and graphene oxide (GO) was modified with 4'-carboxy-2,2':6',2"-terpyridine (CTPy). Then sandwich PVDF-g-4VP/GO-CTPy/polytetrafluoroethylene (PTFE) membrane was fabricated for adsorption of Cu (II) as a model. The membrane formation, static adsorption thermodynamics, kinetics and dynamic adsorption/desorption were studied. The results showed that, the addition of polyethylene glycol (PEG 4000) as porogen can significantly increase the porosity and adsorption capacity of the membranes. The adsorption could be well described by the Langmuir model and pseudo-second-order kinetic model. The breakthrough volume and saturated volume increased with rising GO-CTPy contents. The adsorption capacity of sandwich membranes was much higher than that of mixed matrix membranes. The sandwich membrane also exhibited excellent reusability in dynamic adsorption/desorption cycles, demonstrating great potential in adsorption of trace Cu (II).

10.
J Med Chem ; 61(3): 791-803, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29328655

RESUMO

Inhibition of the mycolic acid pathway has proven a viable strategy in antitubercular drug discovery. The AccA3/AccD4/FadD32/Pks13 complex of Mycobacterium tuberculosis constitutes an essential biosynthetic mechanism for mycolic acids. Small molecules targeting the thioesterase domain of Pks13 have been reported, including a benzofuran-based compound whose X-ray cocrystal structure has been very recently solved. Its initial inactivity in a serum inhibition titration (SIT) assay led us to further probe other structurally related benzofurans with the aim to improve their potency and bioavailability. Herein, we report our preliminary structure-activity relationship studies around this scaffold, highlighting a natural product-inspired cyclization strategy to form coumestans that are shown to be active in SIT. Whole genome deep sequencing of the coumestan-resistant mutants confirmed a single nucleotide polymorphism in the pks13 gene responsible for the resistance phenotype, demonstrating the druggability of this target for the development of new antitubercular agents.


Assuntos
Cumarínicos/química , Cumarínicos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Policetídeo Sintases/antagonistas & inibidores , Animais , Chlorocebus aethiops , Cumarínicos/toxicidade , Inibidores Enzimáticos/toxicidade , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Células Vero
11.
Materials (Basel) ; 9(12)2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-28774106

RESUMO

Intermetallic compounds are increasingly being expected to be utilized in tribological environments, but to date their implementation is hindered by insufficient ductility at low and medium temperatures. This paper presents a novel multiphase intermetallic alloy with the chemical composition of Mo-40Ni-13Si (at %). Microstructure characterization reveals that a certain amount of ductile Mo phases formed during the solidification process of a ternary Mo-Ni-Si molten alloy, which is beneficial to the improvement of ductility of intermetallic alloys. Tribological properties of the designed alloy-including wear resistance, friction coefficient, and metallic tribological compatibility-were evaluated under dry sliding wear test conditions at room temperature. Results suggest that the multiphase alloy possesses an excellent tribological property, which is attributed to unique microstructural features and thereby a good combination in hardness and ductility. The corresponding wear mechanism is explained by observing the worn surface, subsurface, and wear debris of the alloy, which was found to be soft abrasive wear.

12.
Int J Clin Exp Pathol ; 8(9): 11747-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617921

RESUMO

Immunoglobulin G4-related disease (IgG4-RD) is a recently described inflammatory disease involving multiple organs. Prostate involvement with IgG4-RD is very rare. In this report, we describe a case of IgG4-related prostatitis progressed from localized IgG4-related lymphadenopathy. This patient was present with urine retention symptoms. MRI and CT examination revealed the prostatic enlargement and the multiple lymphadenopathy. Serum IgG4 levels were elevated. Prostatic tissue samples resected both this time and less than 1 year earlier showed the same histological type of prostatitis with histopathologic and immunohistochemical findings characteristic of IgG4-RD. The right submandibular lymph nodes excised 2 years earlier were eventually proven to be follicular hyperplasia-type IgG4-related lymphadenopathy. This is the first case of IgG4-RD that began as localized IgG4-related lymphadenopathy and progressed into a systemic disease involving prostate and multiple lymph nodes. This patient showed a good response to steroid therapy. This leads us to advocate a novel pathogenesis of prostatitis, and a novel therapeutic approach against prostatitis. Pathologists and urologists should consider this disease entity in the patients with elevated serum IgG4 levels and the symptoms of prostatic hyperplasia to avoid ineffective medical or unnecessary surgical treatment.


Assuntos
Imunoglobulina G/imunologia , Doenças Linfáticas/imunologia , Doenças Linfáticas/patologia , Prostatite/imunologia , Prostatite/patologia , Idoso , Progressão da Doença , Humanos , Masculino
13.
J Hand Surg Am ; 33(8): 1358-61, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929201

RESUMO

A case of congenital flexion deformity of the long, ring, and little fingers with an aberrant origin of the flexor digitorum profundus is described. The aberrant tendinous band originated from a bone prominence in the medial and anterior aspect of the proximal side of the ulna, which was confirmed in the operation. Resection of the aberrant origin could achieve only partial relief for the flexion contracture of the 3 fingers. Further muscle-sliding procedure was needed to achieve a thorough release.


Assuntos
Dedos/cirurgia , Deformidades Congênitas da Mão/cirurgia , Músculo Esquelético/anormalidades , Músculo Esquelético/cirurgia , Procedimentos Ortopédicos/métodos , Contratura/congênito , Contratura/cirurgia , Dedos/anormalidades , Seguimentos , Deformidades Congênitas da Mão/diagnóstico , Força da Mão , Humanos , Masculino , Amplitude de Movimento Articular/fisiologia , Recuperação de Função Fisiológica/fisiologia , Medição de Risco , Tendões/fisiopatologia , Tendões/cirurgia , Cicatrização/fisiologia , Adulto Jovem
14.
J Hand Surg Am ; 33(6): 869-72, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18656757

RESUMO

A relatively rare case of dorsal dislocation of the distal interphalangeal (DIP) joint associated with compression fracture of volar base of the distal phalanx is presented. An extension block pin was used to maintain the reduction of the DIP joint during active flexion and extension exercise after surgery. At 49-month follow-up, the clinical results and radiographic findings were satisfactory.


Assuntos
Traumatismos dos Dedos/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Luxações Articulares/cirurgia , Adulto , Basquetebol/lesões , Pinos Ortopédicos , Traumatismos dos Dedos/diagnóstico por imagem , Articulações dos Dedos/diagnóstico por imagem , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/diagnóstico por imagem , Humanos , Luxações Articulares/diagnóstico por imagem , Masculino , Radiografia , Amplitude de Movimento Articular
15.
Chin Med J (Engl) ; 119(3): 207-10, 2006 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-16537006

RESUMO

BACKGROUND: To repair late median nerve injury, many methods have been used in the past years. The aim of this study was to review a thirteen-year experience in restoration of thumb opposition by transposing flexor pollicis brevis muscle. METHODS: From July 1992 to August 2005, 63 patients without thumb opposition because of late median never injury were treated by transposing the flexor pollicis brevis muscle. All the patients had received primary nerve repair after the jnjury. The interval between the injury and the second operation was (1.87 +/- 2.31) years (6 months to 4.2 years). The patients were followed up for 3 to 48 [months mean (22.93 +/- 2.31) months]. A functional evaluation system designed in 1992 were used to estimate the outcomes of the patients. RESULTS: All the patients gained excellent functional results without complications and disabilities during follow-up. CONCLUSIONS: Restoration of thumb opposition by transposing flexsor pollicis brevis muscle has the following advantages: 1. Operative trauma is minimal; 2. It is not necessary to transpose other tendons; 3. Except for the thumb in opposition, movements of other fingers and the wrist are not restricted postoperatively.


Assuntos
Traumatismos do Antebraço/cirurgia , Nervo Mediano/lesões , Músculo Esquelético/cirurgia , Polegar/cirurgia , Traumatismos do Punho/cirurgia , Adolescente , Adulto , Fenômenos Biomecânicos , Feminino , Traumatismos do Antebraço/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Transferência Tendinosa , Polegar/fisiopatologia , Traumatismos do Punho/fisiopatologia
16.
Beijing Da Xue Xue Bao Yi Xue Ban ; 36(3): 327-9, 2004 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-15205711

RESUMO

Nonunion remains a major complication after skeletal trauma. In the last decade, extracorporeal shock wave therapy has become a common tool for the treatment of delayed unions or non-unions. With the help of a review of the literature, the current author gave an overview of indications, choices of devices, success rates and complications for ESWT in the treatment of non-unions. The conceivable mechanism was also outlined.


Assuntos
Fraturas não Consolidadas/terapia , Ondas de Choque de Alta Energia/uso terapêutico , Animais , Consolidação da Fratura/fisiologia , Humanos
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