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1.
Int J Med Robot ; 20(4): e2660, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38978325

RESUMO

BACKGROUND: At present, the number and overall level of ultrasound (US) doctors cannot meet the medical needs, and the medical ultrasound robots will largely solve the shortage of medical resources. METHODS: According to the degree of automation, the handheld, semi-automatic and automatic ultrasound examination robot systems are summarised. Ultrasound scanning path planning and robot control are the keys to ensure that the robot systems can obtain high-quality images. Therefore, the ultrasound scanning path planning and control methods are summarised. The research progress and future trends are discussed. RESULTS: A variety of ultrasound robot systems have been applied to various medical works. With the continuous improvement of automation, the systems provide high-quality ultrasound images and image guidance for clinicians. CONCLUSION: Although the development of medical ultrasound robot still faces challenges, with the continuous progress of robot technology and communication technology, medical ultrasound robot will have great development potential and broad application space.


Assuntos
Robótica , Ultrassonografia , Humanos , Ultrassonografia/métodos , Ultrassonografia/instrumentação , Robótica/instrumentação , Desenho de Equipamento , Automação , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Processamento de Imagem Assistida por Computador/métodos
2.
Math Biosci Eng ; 21(5): 5947-5971, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38872565

RESUMO

The technology of robot-assisted prostate seed implantation has developed rapidly. However, during the process, there are some problems to be solved, such as non-intuitive visualization effects and complicated robot control. To improve the intelligence and visualization of the operation process, a voice control technology of prostate seed implantation robot in augmented reality environment was proposed. Initially, the MRI image of the prostate was denoised and segmented. The three-dimensional model of prostate and its surrounding tissues was reconstructed by surface rendering technology. Combined with holographic application program, the augmented reality system of prostate seed implantation was built. An improved singular value decomposition three-dimensional registration algorithm based on iterative closest point was proposed, and the results of three-dimensional registration experiments verified that the algorithm could effectively improve the three-dimensional registration accuracy. A fusion algorithm based on spectral subtraction and BP neural network was proposed. The experimental results showed that the average delay of the fusion algorithm was 1.314 s, and the overall response time of the integrated system was 1.5 s. The fusion algorithm could effectively improve the reliability of the voice control system, and the integrated system could meet the responsiveness requirements of prostate seed implantation.


Assuntos
Algoritmos , Realidade Aumentada , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Próstata , Neoplasias da Próstata , Robótica , Humanos , Masculino , Robótica/instrumentação , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Próstata/diagnóstico por imagem , Imageamento Tridimensional , Voz , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Holografia/métodos , Holografia/instrumentação , Braquiterapia/instrumentação , Reprodutibilidade dos Testes
3.
BMC Genomics ; 25(1): 414, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671371

RESUMO

BACKGROUND: Growth rate is a crucial economic trait for farmed animals, but the genetic regulation of this trait is largely unknown in non-model organisms such as shrimp. RESULTS: In this study, we performed genome-wide phenotypic quantitative trait loci (QTL) and expression quantitative trait loci (eQTL) mapping analyses to identify genes affecting the growth rate of Pacific white shrimp (Litopenaeus vannamei), which is the most commercially-farmed crustacean worldwide. We used RNA-sequencing of 268 individuals in a mapping population, and subsequently validated our findings through gene silencing and shrimp growth experiments. We constructed a high-density genetic linkage map comprising 5533 markers spanning 44 linkage groups, with a total distance of 6205.75 cM and an average marker interval of 1.12 cM. Our analyses identified 11 QTLs significantly correlated with growth rate, and 117,525 eQTLs. By integrating QTL and eQTL data, we identified a gene (metalloreductase STEAP4) highly associated with shrimp growth rate. RNA interference (RNAi) analysis and growth experiments confirmed that STEAP4 was significantly correlated with growth rate in L. vannamei. CONCLUSIONS: Our results indicate that the comprehensive analysis of QTL and eQTL can effectively identify genes involved in complex animal traits. This is important for marker-assisted selection (MAS) of animals. Our work contributes to the development of shrimp breeding and available genetic resources.


Assuntos
Mapeamento Cromossômico , Penaeidae , Locos de Características Quantitativas , Animais , Penaeidae/genética , Penaeidae/crescimento & desenvolvimento , Fenótipo , Ligação Genética , Estudo de Associação Genômica Ampla , Interferência de RNA
4.
Med Eng Phys ; 126: 104156, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38621852

RESUMO

Percutaneous insertion is one of the most common minimally invasive procedures. Compared with traditional straight rigid needles, bevel-tipped flexible needle can generate curved trajectories to avoid obstacles and sensitive organs. However, the nonlinear large deflection problem challenges the bending prediction of the needle, which dramatically influences the surgical success rate. This paper analyzed the mechanism of needle-tissue interaction, and established a mechanics-based model of the needle bending during an insertion. And then, a discretization of the bending model was adopted to accurately predict the large bending of the needle in soft tissue. Insertion experiments were conducted to validate the bending prediction model. The results showed that the large needle bending was predicted with the mean/RMSE/maximumu error of 0.42 mm / 0.26 mm / 1.08 mm, which was clinically acceptable. This proved the rationality and accuracy of the proposed model.


Assuntos
Agulhas
5.
J Hazard Mater ; 469: 133990, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38460261

RESUMO

Heavy metal migration in soil poses a serious threat to the soil and groundwater. Understanding the migration pattern of heavy metals (HMs) under different factors could provide a more reasonable position for pollution evaluation and targetoriented treatment of soil heavy metal. In this study, the migration behavior of Pb and Cd in co-contaminated soil under different pH and ionic strength (NaCl concentration) was simulated using convective dispersion equation (CDE). We predicted the migration trends of Pb and Cd in soils after 5, 10, and 20 years via PHREEQC. The results showed that the migration time of Cd in the soil column experiment was about 60 days faster than that of Pb, and the migration trend was much steeper. The CDE was proved to describe the migration behavior of Pb and Cd (R2 > 0.75) in soil. The predicted results showed that Cd migrated to 15-20 cm of soil within 7 years and Pb stayed mainly in the top 0-6 cm of soil within 5 years as the duration of irrigation increased. Overall, our study is expected to provide new insight into the migration of heavy metal in soil ecosystems and guidance for reducing risk of heavy metal in the environment.

6.
Math Biosci Eng ; 21(1): 523-561, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303433

RESUMO

A flexible needle has emerged as a crucial clinical technique in contemporary medical practices, particularly for minimally invasive interventions. Its applicability spans diverse surgical domains such as brachytherapy, cardiovascular surgery, neurosurgery and others. Notably, flexible needles find utility in biopsies requiring deep skin penetration to access infected areas. Despite its minimally invasive advantages, the precise guidance of the needle to its intended target, while avoiding damage to bones, blood vessels, organs and tissues, remains a significant challenge for researchers. Consequently, extensive research has been dedicated to enhancing the steering and accuracy of flexible needles. Here, we aim to elucidate the recent advancements, trends and perspectives in flexible needle steering models and path planning over the last 15 years. The discussed models encompass various types, including symmetric-tip needles, curved-tip needles, tendon-actuated needles, programmable needles and the innovative fracture-directed waterjet needles. Moreover, the paper offers a comprehensive analysis, comparing the trajectories followed by these needle models to attain the desired target with minimal tissue damage. By delving into these aspects, the paper contributes to a deeper understanding of the current landscape of flexible needle technology and guides future research directions in this dynamic field.


Assuntos
Robótica , Agulhas , Imagens de Fantasmas
7.
Int J Numer Method Biomed Eng ; 40(1): e3789, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37899669

RESUMO

The incidence of oral malocclusion is increasing and is seriously damaging the oral health of human beings. The Kitchon root-controlled auxiliary archwire is an individualized orthodontic arch. It is used clinically for the treatment of tooth-lingual tilt/root-lip tilt phenomenon of the central incisors. However, the bending parameters of the Kitchon root-controlled auxiliary archwire used in different patients are based on the clinical experience of the dentists. Therefore, this orthodontic treatment has a high risk and unpredictability. In this paper, the loading performance and orthodontic process of Kitchon root-controlled auxiliary archwire are analyzed. And the prediction model of support resistance and correction torque are established. The bending parameters of the Kitchon root-controlled auxiliary archwire, as well as the effect of the bending parameters on the support resistance and the correction torque, are all quantified. And the prediction models for the support resistance and the correction torque are calculated separately. The correlation coefficients of calculated data and experimental data are ξT1 > .97 and ξA1 > .96, respectively; the correlation coefficients of simulated data and experimental data are ξT2 > .96 and ξA2 > .96, respectively. The accuracy and reliability of the established prediction models are verified. It provides an effective theoretical guide for dentists to safely and efficiently perform root-controlled rotation orthodontic treatment on patients' central incisors.


Assuntos
Fios Ortodônticos , Dente , Humanos , Torque , Reprodutibilidade dos Testes , Fenômenos Mecânicos
8.
J Adv Res ; 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38043610

RESUMO

INTRODUCTION: Golden pompano (Trachinotus ovatus) is economically significant important for offshore cage aquaculture in China and Southeast Asian countries. Lack of high-quality genomic data and accurate gene annotations greatly restricts its genetic breeding progress. OBJECTIVES: To decode the mechanisms of sex determination and rapid growth in golden pompano and facilitate the sex- and growth-aimed genetic breeding. METHODS: Genome assemblies of male and female golden pompano were generated using Illumina, PacBio, BioNano, genetic maps and Hi-C sequencing data. Genomic comparisons, whole genome re-sequencing of 202 F1 individuals, QTL mapping and gonadal transcriptomes were used to analyze the sex determining region, sex chromosome evolution, SNP loci, and growth candidate genes. Zebrafish model was used to investigate the functions of growth candidate gene. RESULTS: Female (644.45 Mb) and male (652.12 Mb) genomes of golden pompano were assembled and annotated at the chromosome level. Both genomes are highly conserved and no new or highly differentiated sex chromosomes occur. A 3.5 Mb sex determining region on LG15 was identified, where Hsd17b1, Micall2 and Lmx1a were putative candidates for sex determination. Three SNP loci significantly linked to growth were pinpointed, and a growth-linked gene gpsstr1 was identified by locus BSNP1369 (G â†’ C, 17489695, Chr23). Loss of sstr1a (homologue of gpsstr1) in zebrafish caused growth retardation. CONCLUSION: This study provides insights into sex chromosome evolution, sex determination and rapid growth of golden pompano.

9.
Cogn Neurodyn ; 17(6): 1561-1573, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37974581

RESUMO

Deep convolutional neural networks have achived remarkable progress on computer vision tasks over last years. These novel neural architecture are most designed manually by human experts, which is a time-consuming process and not the best solution. Hence neural architecture search (NAS) has become a hot research topic for the design of neural architecture. In this paper, we propose the dynamic receptive field (DRF) operation and measurable dense residual connections (DRC) in search space for designing efficient networks, i.e., DRENet. The search method can be deployed on the MobileNetV2-based search space. The experimental results on CIFAR10/100, SVHN, CUB-200-2011, ImageNet and COCO benchmark datasets and an application example in a railway intelligent surveillance system demonstrate the effectiveness of our scheme, which achieves superior performance.

10.
Sensors (Basel) ; 23(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37960395

RESUMO

In this paper we outline newly-developed control algorithms, designed to achieve high-precision feedback for a motor control system using a magnetic encoder. The magnetic encoder, combing single-pole and multi-pole magnetic steels, was adopted to extend the resolution of the magnetic encoder. First, with a view to settling the issue of the jump points of the multi-pole angle value at the convergence of two adjacent magnetic poles, the angle segmentation method, which uses the window filter discrimination method, is employed to determine the actual angle value. The appropriate filter window width is selected via the improved particle swarm optimization (IPSO) algorithm, and an expanded resolution is achieved. Second, a compensation table is completed via a linear compensation algorithm based on virtual cutting to enhance the accuracy of the combined magnetic encoder. On this basis, a linear difference algorithm is used to achieve deviation correction of the angle. Finally, the jump points can be restrained effectively via the angle segmentation method. The resolution reaches 0.05°, and the accuracy is 0.045°.

11.
Artigo em Inglês | MEDLINE | ID: mdl-37886790

RESUMO

Point-of-care detection of tumor biomarkers with high sensitivity remains an enormous challenge in the early diagnosis and mass screening of cancer. Fluorescent lateral flow immunoassay (LFA) is an attractive platform for point-of-care testing due to its inherent advantages. Particularly, a fluorescent probe is crucial to improving the analytical performance of the LFA platform. Herein, we developed an enhanced second near-infrared (NIR-II) LFA (ENIR-II LFA) platform based on supramolecular host-guest self-assembly for detection of the prostate-specific antigen (PSA) as a model analyte. In this platform, depending on the effective supramolecular surface modification strategy, cucurbit[7]uril (CB[7])-covered rare-earth nanoparticles (RENPs) emitting in the NIR-II (1000-1700 nm) window were prepared and employed as an efficient fluorescent probe (RENPs-CB[7]). Benefiting from its superior optical properties, such as low autofluorescence, excellent photostability, enhanced fluorescence intensity, and increased antibody-conjugation efficiency, the ENIR-II LFA platform displayed a wide linear detection range from 0.65 to 120 ng mL-1, and the limit of detection was down to 0.22 ng mL-1 for PSA, which was 18.2 times lower than the clinical cutoff value. Moreover, the testing time was also shortened to 6 min. Compared with the commercial visible fluorescence LFA kit (VIS LFA) and the previously reported NIR-II LFA based on a RENPs-PAA probe, this ENIR-II LFA demonstrated more competitive advantages in analytical sensitivity, detection range, testing time, and production cost. Overall, the ENIR-II LFA platform offers great potential for the highly sensitive, rapid, and convenient detection of tumor biomarkers and is expected to serve as a useful technique in the general population screening of the high-incidence cancer region.

12.
Math Biosci Eng ; 20(8): 15135-15166, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37679175

RESUMO

At present, the incidence of prostate cancer (PCa) in men is increasing year by year. So, the early diagnosis of PCa is of great significance. Transrectal ultrasonography (TRUS)-guided biopsy is a common method for diagnosing PCa. The biopsy process is performed manually by urologists but the diagnostic rate is only 20%-30% and its reliability and accuracy can no longer meet clinical needs. The image-guided prostate biopsy robot has the advantages of a high degree of automation, does not rely on the skills and experience of operators, reduces the work intensity and operation time of urologists and so on. Capable of delivering biopsy needles to pre-defined biopsy locations with minimal needle placement errors, it makes up for the shortcomings of traditional free-hand biopsy and improves the reliability and accuracy of biopsy. The integration of medical imaging technology and the robotic system is an important means for accurate tumor location, biopsy puncture path planning and visualization. This paper mainly reviews image-guided prostate biopsy robots. According to the existing literature, guidance modalities are divided into magnetic resonance imaging (MRI), ultrasound (US) and fusion image. First, the robot structure research by different guided methods is the main line and the actuators and material research of these guided modalities is the auxiliary line to introduce and compare. Second, the robot image-guided localization technology is discussed. Finally, the image-guided prostate biopsy robot is summarized and suggestions for future development are provided.


Assuntos
Neoplasias da Próstata , Robótica , Masculino , Humanos , Próstata/diagnóstico por imagem , Reprodutibilidade dos Testes , Biópsia , Neoplasias da Próstata/diagnóstico por imagem
13.
Sensors (Basel) ; 23(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37765764

RESUMO

Traditional methods for obtaining soil heavy metal content are expensive, inefficient, and limited in monitoring range. In order to meet the needs of soil environmental quality evaluation and health status assessment, visible near-infrared spectroscopy and XRF spectroscopy for monitoring heavy metal content in soil have attracted much attention, because of their rapid, nondestructive, economical, and environmentally friendly features. The use of either of these spectra alone cannot meet the accuracy requirements of traditional measurements, while the synergistic use of the two spectra can further improve the accuracy of monitoring heavy metal lead content in soil. Therefore, this study applied various spectral transformations and preprocessing to vis-NIR and XRF spectra; used the whale optimization algorithm (WOA) and competitive adaptive re-weighted sampling (CARS) algorithms to identify feature spectra; designed a combination variable model (CVM) based on multi-layer spectral data fusion, which improved the spectral preprocessing and spectral feature screening process to increase the efficiency of spectral fusion; and established a quantitative model for soil Pb concentration using partial least squares regression (PLSR). The estimation performance of three spectral fusion strategies, CVM, outer-product analysis (OPA), and Granger-Ramanathan averaging (GRA), was discussed. The results showed that the accuracy and efficiency of the CARS algorithm in the fused spectra estimation model were superior to those of the WOA algorithm, with an average coefficient of determination (R2) value of 0.9226 and an average root mean square error (RMSE) of 0.1984. The accuracy of the estimation models established, based on the different spectral types, to predict the Pb content of the soil was ranked as follows: the CVM model > the XRF spectral model > the vis-NIR spectral model. Within the CVM fusion strategy, the estimation model based on CARS and PLSR (CARS_D1+D2) performed the best, with R2 and RMSE values of 0.9546 and 0.2035, respectively. Among the three spectral fusion strategies, CVM had the highest accuracy, OPA had the smallest errors, and GRA showed a more balanced performance. This study provides technical means for on-site rapid estimation of Pb content based on multi-source spectral fusion and lays the foundation for subsequent research on dynamic, real-time, and large-scale quantitative monitoring of soil heavy metal pollution using high-spectral remote sensing images.

14.
J Environ Radioact ; 262: 107168, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37003252

RESUMO

Arsenic (As) and uranium (U) frequently occur together naturally and, in consequence, transform into cocontaminants at sites of uranium mining and processing, yet the simultaneous interaction process of arsenic and uranium has not been well documented. In the present contribution, the influence of arsenate on the removal and reduction of uranyl by the indigenous microorganism Kocuria rosea was characterized using batch experiments combined with species distribution calculation, SEM-EDS, FTIR, XRD and XPS. The results showed that the coexistence of arsenic plays an active role in Kocuria rosea growth and the removal of uranium under neutral and slightly acidic conditions. U-As complex species of UO2HAsO4 (aq) had a positive effect on uranium removal, while Kocuria rosea cells appeared to have a large specific surface area serving as attachment sites. Furthermore, a large number of nano-sized flaky precipitates, constituted by uranium and arsenic, attached to the surface of Kocuria rosea cells at pH 5 through P=O, COO-, and C=O groups in phospholipids, polysaccharides, and proteins. The biological reduction of U(VI) and As(V) took place in a successive way, and the formation of a chadwickite-like uranyl arsenate precipitate further inhibited U(VI) reduction. The results will help to design more effective bioremediation strategies for arsenic-uranium cocontamination.


Assuntos
Arsênio , Monitoramento de Radiação , Urânio , Arseniatos/química , Urânio/metabolismo
15.
Ann Biomed Eng ; 51(5): 905-924, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36943414

RESUMO

Accurate needle targeting is critical for many clinical procedures, such as transcutaneous biopsy or radiofrequency ablation of tumors. However, targeting errors may arise, limiting the widespread adoption of these procedures. Advances in flexible needle (FN) steering are emerging to mitigate these errors. This review summarizes the state-of-the-art developments of FNs and addresses possible targeting errors that can be overcome with steering actuation techniques. FN steering techniques can be classified as passive and active. Passive steering directly results from the needle-tissue interaction forces, whereas active steering requires additional forces to be applied at the needle tip, which enhances needle steerability. Therefore, the corresponding targeting errors of most passive FNs and active FNs are between 1 and 2 mm, and less than 1 mm, respectively. However, the diameters of active FNs range from 1.42 to 12 mm, which is larger than the passive steering needle varying from 0.5 to 1.4 mm. Therefore, the development of active FNs is an area of active research. These active FNs can be steered using tethered internal direct actuation or untethered external actuation. Examples of tethered internal direct actuation include tendon-driven, longitudinal segment transmission and concentric tube transmission. Tendon-driven FNs have various structures, and longitudinal segment transmission needles could be adapted to reduce tissue damage. Additionally, concentric tube needles have immediate advantages and clinical applications in natural orifice surgery. Magnetic actuation enables active FN steering with untethered external actuation and facilitates miniaturization. The challenges faced in the fabrication, sensing, and actuation methods of FN are analyzed. Finally, bio-inspired FNs may offer solutions to address the challenges faced in FN active steering mechanisms.


Assuntos
Agulhas , Miniaturização , Imagens de Fantasmas , Biópsia
16.
Genes Genomics ; 44(12): 1487-1498, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36244041

RESUMO

BACKGROUND: Holothuria scabra is a costly gourmet and traditional Chinese tonic medicine. However, the lack of high-quality genome information hinders the genetic, phylogenetic, and bioactivator researches. OBJECTIVE: To construct high-quality genomic data of H. scabra and conduct genome-wide phylogenetic analysis. METHODS: The whole genome of a male H. scabra was sequenced based on Nanopore MinION platform, and the sequence was assembled by wtdbg2. Transcriptome sequencing was used to aid the gene annotation. Repeat sequences, non-coding RNA, pseudogene and gene functional annotation were analyzed. 750 single-copy gene families from ten species were applied to construct phylogenetic tree for evolutionary analysis by using the ML method. RESULTS: The H. scabra genome of 1.18 Gb (N50 = 1557,492 bp) with 500.42 Mb of putative repetitive sequences was assembled from a male H. scabra individual, and 16,642 protein-coding genes, 951 pseudogenes, 1791 motifs and 45,400 domains from the generated assembly were identified. The divergence time between H. scabra and its ancestor was estimated approximately 192.6 million years ago. H. scabra and A. japonicas joined together while sea urchin and sea star diverged about 440 Mya ago. Some key genes involved in notochord and gill slits development, skeleton degeneration and nervous system, as well as homeobox genes differ between H. scabra and Apostichopus japonicas. CONCLUSION: We report the first whole genome of H. scabra with expectation that this will be a valuable resource for genetic, phylogenetic, breading, molecular biology and bioactivator studies of sea cucumbers and other invertebrates.


Assuntos
Holothuria , Sequenciamento por Nanoporos , Nanoporos , Animais , Holothuria/genética , Filogenia , Anotação de Sequência Molecular
17.
Comput Intell Neurosci ; 2022: 9752003, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262616

RESUMO

The reptile search algorithm (RSA) is a swarm-based metaheuristic algorithm inspired by the encirclement and hunt mechanisms of crocodiles. Compared with other algorithms, RSA is competitive but still suffers from low population diversity, unbalanced exploitation and exploration, and the tendency to fall into local optima. To overcome these shortcomings, a modified variant of RSA, named MRSA, is proposed in this paper. First, an adaptive chaotic reverse learning strategy is employed to enhance the population diversity. Second, an elite alternative pooling strategy is proposed to balance exploitation and exploration. Finally, a shifted distribution estimation strategy is used to correct the evolutionary direction and improve the algorithm performance. Subsequently, the superiority of MRSA is verified using 23 benchmark functions, IEEE CEC2017 benchmark functions, and robot path planning problems. The Friedman test, the Wilcoxon signed-rank test, and simulation results show that the proposed MRSA outperforms other comparative algorithms in terms of convergence accuracy, convergence speed, and stability.


Assuntos
Algoritmos , Benchmarking , Animais , Simulação por Computador , Aprendizagem , Répteis
18.
BMC Oral Health ; 22(1): 406, 2022 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-36115965

RESUMO

BACKGROUND: The T-loop has been used clinically to close gap between teeth. And it is a typical orthodontic archwire bending method. However, the design of the T-loop parameters for different patients is based on the clinical experience of the dentists. The variation in dentists' clinical experience is the main reason for inadequate orthodontic treatment, even high incidence of postoperative complications. METHODS: Firstly, the tooth movement prediction model is established based on the analysis of the T-loop structure and the waxy model dynamic resistance. As well as the reverse reconstruction of the complete maxillary 3D model based on the patient CBCT images, the oral biomechanical FEM analysis is completed. A maxillary waxy dental model is manufactured to realize the water-bath measurement experiment in vitro mimicking the oral bio-environment. Thus, the calculated, simulation and experimental data are obtained, as well as obtaining a cloud of total deformation from the simulation analysis. RESULTS: The growth trend of the 11 sets of simulation data is the same as that of the experimental data. And all of them show that the tooth displacement is positively correlated with the cross-sectional size of the archwire, and the clearance distance. As well as the higher Young's modulus of the archwire material, the greater the tooth displacement. And the effect of archwire parameters on tooth displacement derived from simulation and experimental data is consistent with the prediction model. The experimental and calculated data are also compared and analyzed, and the two kinds of data are basically consistent in terms of growth trends and fluctuations, with deviation rates ranging from 2.17 to 10.00%. CONCLUSIONS: This study shows that the accuracy and reliability of the tooth movement prediction model can be verified through the comparative analysis and deviation calculation of the obtained calculated, simulation and experimental data, which can assist dentists to safely and efficiently perform orthodontic treatment on patients. And the FEM analysis can achieve predictability of orthodontic treatment results.


Assuntos
Fios Ortodônticos , Técnicas de Movimentação Dentária , Estudos Transversais , Humanos , Reprodutibilidade dos Testes , Técnicas de Movimentação Dentária/métodos , Água
19.
Comput Assist Surg (Abingdon) ; 27(1): 91-112, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36052822

RESUMO

In the field of minimally invasive interventional therapy, the related research on the soft tissue puncture robot and its technology based on the flexible steerable needle as a research hot topic at present, and it has been developed rapidly in the past ten years. In order to better understand the development status of the flexible steerable needle puncture (FSNP) robot and provide reference for its design and improvement in subsequent research, it is necessary to introduce in two aspects of FSNP robot: the puncture path planning and the control methods. First, this article introduced the concept of the FSNP technology, and the necessity of the application of FSNP soft tissue robot in minimally invasive interventional surgery. Second, this article mainly introduced the principle of FSNP, the path planning of FSNP, the navigation and positioning control of the needle tip of the flexible steerable needle, the control method of FSNP system, and the controllable flexible needle. Finally, combined with the above analysis and introduction, it was pointed out that FSNP soft tissue robot and its related technology would be an important development direction in the field of minimally invasive interventional therapy in the future, and the current existing problems were pointed out. Meanwhile, the development trend of FSNP robot control technology was summarized and prospected.


Assuntos
Robótica , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , Agulhas , Punções , Robótica/métodos
20.
Int J Med Robot ; 18(3): e2388, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35253985

RESUMO

BACKGROUND: Transrectal prostate brachytherapy (BT) involves the permanent implantation of radioactive seeds through a needle, which must be inserted along a straight path to satisfy dose distribution requirements. However, this process is complicated by bevelled needle tips that can cause deflection during penetration. In clinical practice, physicians typically rotate the bevelled tip intermittently or apply manual correction forces near the insertion point, to reduce needle deflection. While assisted rotational insertion robots have made substantial progress in the past 20 years, tissue sticking can be caused by rotation of the bevelled tip and there are currently few studies on the use of corrective forces. As such, an auxiliary needle insertion guide for transrectal prostate BT, based on corrective forces, is investigated in this study for the first time. METHODS: The proposed BT guide is designed to reduce needle deflection and was experimentally verified by in vitro experiments. An energy-based deflection model was developed to predict needle motion as corrective forces were applied during insertion. An experimental platform was constructed to perform corrective force-assisted punctures, using the magnitude of the corrective force (A), the position of corrective force application (B) and the puncture speed (C) as test factors, with needle deflection as a test indicator. Design-Expert 8.0.5b software was used for simulation, and a high-definition camera acquired pictures of the needle tip as it pierced the tissue. A regression equation was also established for the test factors and test indicators, using Design-Expert software. Optimal parameter combinations (A, B and C) were determined through optimization. RESULTS: Calculated needle deflection values were then compared with the measured position of the needle insertion point, producing an average error of 0.39 ± 0.28 mm. Deflection was as low as 0.8 mm using optimal puncture parameters CONCLUSIONS: A needle-tissue interaction model, considering tissue nonlinearity, which experimental results demonstrated to be highly accurate. Optimal puncture parameters effectively improved puncture accuracy.


Assuntos
Braquiterapia , Braquiterapia/métodos , Humanos , Masculino , Agulhas , Próstata , Punções/métodos , Rotação
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