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1.
Magn Reson Med ; 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36063493

RESUMO

PURPOSE: This work introduces and validates a deep-learning-based fitting method, which can rapidly provide accurate and robust estimation of cytological features of brain tumor based on the IMPULSED (imaging microstructural parameters using limited spectrally edited diffusion) model fitting with diffusion-weighted MRI data. METHODS: The U-Net was applied to rapidly quantify extracellular diffusion coefficient (Dex ), cell size (d), and intracellular volume fraction (vin ) of brain tumor. At the training stage, the image-based training data, synthesized by randomizing quantifiable microstructural parameters within specific ranges, was used to train U-Net. At the test stage, the pre-trained U-Net was applied to estimate the microstructural parameters from simulated data and the in vivo data acquired on patients at 3T. The U-Net was compared with conventional non-linear least-squares (NLLS) fitting in simulations in terms of estimation accuracy and precision. RESULTS: Our results confirm that the proposed method yields better fidelity in simulations and is more robust to noise than the NLLS fitting. For in vivo data, the U-Net yields obvious quality improvement in parameter maps, and the estimations of all parameters are in good agreement with the NLLS fitting. Moreover, our method is several orders of magnitude faster than the NLLS fitting (from about 5 min to <1 s). CONCLUSION: The image-based training scheme proposed herein helps to improve the quality of the estimated parameters. Our deep-learning-based fitting method can estimate the cell microstructural parameters fast and accurately.

2.
J Med Virol ; 2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36089764

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused extensive loss of life worldwide. Further, the COVID-19 and influenza mix-infection had caused great distress to the diagnosis of the disease. To control illness progression and limit viral spread within the population, a real-time reverse-transcription PCR (RT-PCR) assay for early diagnosis of COVID-19 was developed, but detection was time-consuming (4-6 h). To improve the diagnosis of COVID-19 and influenza, we herein developed a recombinase polymerase amplification (RPA) method for simple and rapid amplification of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19 and Influenza A (H1N1, H3N2) and B (influenza B). Genes encoding the matrix protein (M) for H1N1, and the hemagglutinin (HA) for H3N2, and the polymerase A (PA) for Influenza B, and the nucleocapsid protein (N), the RNA-dependent-RNA polymerase (RdRP) in the open reading frame 1ab (ORF1ab) region, and the envelope protein (E) for SARS-CoV-2 were selected, and specific primers were designed. We validated our method using SARS-CoV-2, H1N1, H3N2 and influenza B plasmid standards and RNA samples extracted from COVID-19 and Influenza A/B (RT-PCR-verified) positive patients. The method could detect SARS-CoV-2 plasmid standard DNA quantitatively between 102 and 105 copies/ml with a log linearity of 0.99 in 22 min. And this method also be very effective in simultaneous detection of H1N1, H3N2 and influenza B. Clinical validation of 100 cases revealed a sensitivity of 100% for differentiating COVID-19 patients from healthy controls when the specificity was set at 90%. These results demonstrate that this nucleic acid testing method is advantageous compared with traditional PCR and other isothermal nucleic acid amplification methods in terms of time and portability. This method could potentially be used for detection of SARS-CoV-2, H1N1, H3N2 and influenza B, and adapted for point-of-care (POC) detection of a broad range of infectious pathogens in resource-limited settings.

3.
ACS Infect Dis ; 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36095241

RESUMO

Harnessing highly conserved peptides derived from the receptor binding domain (RBD) of spike (S) protein to construct peptide-based inhibitors is one of the most effective strategies to fight against the ever-mutating coronavirus SARS-CoV-2. But how the O-glycosylation affects their inhibition abilities has not been intensively explored. Herein, an intrinsic O-glycosylated peptide P320-334 derived from RBD was screened and homogeneous O-linked glycopeptides containing Tn (GalNAcα1-O-Ser/Thr), T (Galß1-3GalNAcα1-O-Ser/Thr), sialyl-Tn (sTn, Siaα2-6GalNAcα1-O-Ser/Thr), and sialyl-T (sT, Siaα2-3Galß1-3GalNAcα1-O-Ser/Thr) structures were first synthesized via chemoenzymatic strategies. Compared with the unglycosylated peptide, the binding of sT-P320-334 to hACE2 was enhanced to 133% and the inhibition capacity against RBD-hACE2 binding of sTn- and sT-P320-334 was significantly increased up to 150-410%. Thus, our results suggest the sialic acid residue on the terminal of short O-glycan structures might strengthen the inhibition capacities of these peptide-based inhibitors, which might provide novel optimization directions for the inhibitor design.

4.
Front Bioeng Biotechnol ; 10: 892613, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091439

RESUMO

Recent studies have confirmed the existence of microbiota in the lungs. The relationship between lung ground-glass opacity (GGO) and microbiota in the lung microenvironment is not clear. In this study, we investigated the microbial composition and diversity in bronchoalveolar lavage fluid (BALF) of diseased lung segments and paired contralateral healthy lung segments from 11 GGO patients. Furthermore, lung GGO and paired normal tissues of 26 GGO patients were explored whether there are microbial characteristics related to GGO. Compared with the control group, the community richness of GGO tissue and BALF of GGO lung segment (α-diversity) and overall microbiome difference (ß-diversity) had no significant difference. The microbiome composition of BALF of GGO segments is distinct from that of paired healthy lung segments [genus (Rothia), order (Lachnospiraceae), family (Lachnospiraceae), genus (Lachnospiraceae_NK4A136_group, Faecalibacterium), and species (Faecalibacterium prausnitzii, Bacteroides uniforms)]. GGO tissue and adjacent lung tissue had more significant differences at the levels of class, order, family, genus, and species level, and most of them are enriched in normal lung tissue. The area under the curve (AUC) using 10 genera-based biomarkers to predict GGO was 91.05% (95% CI: 81.93-100%). In conclusion, this study demonstrates there are significant differences in the lower respiratory tract and lung microbiome between GGO and the non-malignant control group through the BALF and lung tissues. Furthermore, some potential bacterial biomarkers showed good performance to predict GGO.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35793269

RESUMO

AIMS: This study aims to validate and compare the feasibility of T1ρ and native longitudinal relaxation time (T1) mapping in detection of myocardial fibrosis in patients with non-ischaemic cardiomyopathy, focusing on the performance of both methods in identifying late gadolinium enhancement (LGE) grey zone. METHODS AND RESULTS: Twenty-seven hypertrophic cardiomyopathy (HCM) patients, 16 idiopathic dilated cardiomyopathy (DCM) patients, and 18 healthy controls were prospectively enrolled for native T1 and T1ρ mapping imaging and then all the patients underwent enhancement scan for LGE extent and extracellular volume (ECV) values. In LGE positive patients, the LGE areas were divided into LGE core (6 SDs above remote myocardium) and grey zone (2-6 SDs above remote myocardium) according to the signal intensity of LGE. Both HCM and DCM patients showed significantly higher native T1 values and T1ρ values than controls no matter the presence of LGE (all P < 0.01). There were significant differences in native T1 and T1ρ values among four different types of myocardia (LGE core, grey zone, remote area and control, P < 0.0001). However, the T1ρ values of grey zone were significantly higher than control (P < 0.01), while the native T1 values were not (P = 0.089). T1ρ values were significantly associated with both native T1 values (r = 0.54, P < 0.001) and ECV values (r = 0.54, P < 0.001). CONCLUSION: T1ρ mapping is a feasible method to detect myocardial fibrosis in patients with non-ischaemic cardiomyopathy no matter the presence of LGE. Compared with native T1, T1ρ may serve as a better discriminator in the identification of LGE grey zone.

6.
Materials (Basel) ; 15(13)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35806606

RESUMO

Bamboo fibers are considered as a more attractive option for the reinforcement of wood plastic composites as compared to wood fiber due to its fast growth rate and good toughness. Heat treatment is an environment-friendly method of improving the integrated performance of bamboo materials. This paper highlights the heat treatment of bamboo fiber for suitable properties as reinforcements in bamboo plastic composites. The effects of vacuum heat treatment on the surface characteristics of bamboo fibers and the properties of bamboo plastic composites were analyzed by studying the chemical composition, surface elements and polarity of bamboo fiber before and after treatment, and the physical and mechanical properties of bamboo plastic composite. The results showed that after vacuum heat treatment, the bamboo fibers became darker and experienced a transition from green to red. Moreover, FTIR, XPS and contact angle analysis indicated that the hemicellulose content, the oxygen/carbon ratio and the polar component of the bamboo fiber had a decreasing trend as the treatment temperature increased. In addition, the 24 h water absorption and the 24 h thickness expansion rate of the water absorption showed a trend of first decreasing and then increasing as the treatment temperature increased, while the bending performance of bamboo plastic composite showed a trend of increasing first and then decreasing as a result of increased treatment temperature. Therefore, a combined process of vacuum heat treatment and the addition of MAPE could improve the physical and mechanical properties of bamboo plastic composites to a certain extent.

7.
Asian J Androl ; 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35848705

RESUMO

Wenzhou has improved its environmental quality because of comprehensive environmental remediation; nevertheless, the semen quality of infertile males remains unclear. This study determined whether better environmental quality improved semen quality in this region. We recorded semen quality data from 22 962 infertile males from January 2014 to November 2019 at the Center for Reproductive Health of The First Affiliated Hospital of Wenzhou Medical University (Wenzhou, China). Patients were predominantly 30-35 years old (33.1%) and workers (82.0%), with high school education or lower (77.6%); more than a half of the patients (52.6%) were Wenzhou household registration; and most patients (77.5%) had abnormal semen quality. Patients who were older than 40 years and workers, and those with Wenzhou household registration, had significantly worse semen quality (all P < 0.05). From 2014 to 2019, progressive sperm motility, total sperm motility, and semen volume showed increasing linear trends in all patients (P = 0.021, 0.030, and 0.005, respectively), yet normal sperm morphology showed a linearly decreasing trend (P = 0.046). Sensitivity analyses for subgroups yielded similar results. In conclusion, the improvement of environmental quality and better function of the accessory glands are associated with progressive sperm motility, total sperm motility, and semen volume. Normal sperm morphology is influenced by occupational exposures and personal lifestyle and does not improve with environmental quality.

8.
Lung Cancer ; 170: 141-147, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35780588

RESUMO

OBJECTIVE: The optimal extent of lymph node dissection (LND) remains controversial. We aimed to investigate whether the addition of station 4L lymph node dissection (S4L-LND) was beneficial for non-small cell lung cancer (NSCLC). METHODS: Data on 1040 left-sided NSCLC patients undergoing rigorous systematic LND were retrospectively reviewed. Multivariate logistic regression analysis determined risk factors of station 4L (S4L) nodal involvement to facilitate risk stratified analysis of the significance of S4L-LND. Propensity score matching (PSM) was conducted to reduce disparities of baseline characteristics between S4L-LND group and no-S4L-LND group. Recurrence-free survival (RFS), overall survival (OS), and postoperative complications were compared. RESULTS: S4L-LND was performed in 586 (56.3%) patients. The S4L nodal involvement rate was 15.5% (91/586). Aortopulmonary zone nodes involvement (P < 0.001), N1 nodes involvement (P < 0.001), and advanced T stage (P = 0.015) were independent risk factors of S4L nodal involvement. Patients with ≥ 2 risk factors of S4L nodal involvement were classified as high risk group, and the others were classified as low risk group. Among patients with negative aortopulmonary zone nodes and inferior mediastinal nodes (n = 425), only 28 (6.6%) patients had S4L involvement. After PSM, a total of 416 pairs were well matched. There was no significant survival difference between S4L-LND group and no-S4L-LND group (OS, P = 0.247; RFS, P = 0.569). When stratified by risk subgroup, S4L-LND group did not demonstrate superior survival than no-S4L-LND group in the high risk group (OS, P = 0.273; RFS, P = 0.754) or the low risk group (OS, P = 0.558; RFS, P = 0.319). S4L-LND group demonstrated significantly greater risk of postoperative complications than no-S4L-LND group (9.6% vs. 5.8%; P = 0.037). CONCLUSIONS: S4L involvement was not rare and usually occurred with multiple nodal stations involvement. Routine dissection of aortopulmonary zone and inferior mediastinal nodes was sufficient to ensure staging accuracy. The addition of S4L-LND did not improve survival, but might increase the risk of postoperative complications.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/patologia , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática/patologia , Estadiamento de Neoplasias , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
9.
Int J Comput Assist Radiol Surg ; 17(10): 1923-1931, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35794409

RESUMO

PURPOSE: The gene mutation status of isocitrate dehydrogenase (IDH) in gliomas leads to a different prognosis. It is challenging to perform automated tumor segmentation and genotype prediction directly using label-deprived multimodal magnetic resonance (MR) images. We propose a novel framework that employs a domain adaptive mechanism to address this issue. METHODS: Multimodal domain adaptive segmentation (MDAS) framework was proposed to solve the gap issue in cross dataset model transfer. Image translation was used to adaptively align the multimodal data from two domains at the image level, and segmentation consistency loss was proposed to retain more pathological information through semantic constraints. The data distribution between the labeled public dataset and label-free target dataset was learned to achieve better unsupervised segmentation results on the target dataset. Then, the segmented tumor foci were used as a mask to extract the radiomics and deep features. And the subsequent prediction of IDH gene mutation status was conducted by training a random forest classifier. The prediction model does not need any expert segmented labels. RESULTS: We implemented our method on the public BraTS 2019 dataset and 110 astrocytoma cases of grade II-IV brain tumors from our hospital. We obtained a Dice score of 77.41% for unsupervised tumor segmentation, a genotype prediction accuracy (ACC) of 0.7639 and an area under curve (AUC) of 0.8600. Experimental results demonstrate that our domain adaptive approach outperforms the methods utilizing direct transfer learning. The model using hybrid features gives better results than the model using radiomics or deep features alone. CONCLUSIONS: Domain adaptation enables the segmentation network to achieve better performance, and the extraction of mixed features at multiple levels on the segmented region of interest ensures effective prediction of the IDH gene mutation status.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Genótipo , Glioma/diagnóstico por imagem , Glioma/genética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética/métodos
10.
Nat Commun ; 13(1): 4177, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853940

RESUMO

Soft magneto-active machines capable of magnetically controllable shape-morphing and locomotion have diverse promising applications such as untethered biomedical robots. However, existing soft magneto-active machines often have simple structures with limited functionalities and do not grant high-throughput production due to the convoluted fabrication technology. Here, we propose a facile fabrication strategy that transforms 2D magnetic sheets into 3D soft magneto-active machines with customized geometries by incorporating origami folding. Based on automated roll-to-roll processing, this approach allows for the high-throughput fabrication of soft magneto-origami machines with a variety of characteristics, including large-magnitude deploying, sequential folding into predesigned shapes, and multivariant actuation modes (e.g., contraction, bending, rotation, and rolling locomotion). We leverage these abilities to demonstrate a few potential applications: an electronic robot capable of on-demand deploying and wireless charging, a mechanical 8-3 encoder, a quadruped robot for cargo-release tasks, and a magneto-origami arts/craft. Our work contributes for the high-throughput fabrication of soft magneto-active machines with multi-functionalities.


Assuntos
Locomoção , Rotação
11.
Med Phys ; 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35765150

RESUMO

BACKGROUND: Quantitative magnetic resonance imaging provides robust biomarkers in clinics. Nevertheless, the lengthy scan time reduces imaging throughput and increases the susceptibility of imaging results to motion. In this context, a single-shot T2 mapping method based on multiple overlapping-echo detachment (MOLED) planar imaging was presented, but the relatively small echo time range limits its accuracy, especially in tissues with large T2 . PURPOSE: In this work we proposed a novel single-shot method, Multi-Echo-Train Multiple OverLapping-Echo Detachment (METMOLED) planar imaging, to accommodate a large range of T2 quantification without additional measurements to rectify signal degeneration arisen from refocusing pulse imperfection. METHODS: Multiple echo-train techniques were integrated into the MOLED sequence to capture larger TE information. Maps of T2 , B1 , and spin density were reconstructed synchronously from acquired METMOLED data via multitask deep learning. A typical U-Net was trained with 3000/600 synthetic data with geometric/brain patterns to learn the mapping relationship between METMOLED signals and quantitative maps. The refocusing pulse imperfection was settled through the inherent information of METMOLED data and auxiliary tasks. RESULTS: Experimental results on the digital brain (structural similarity (SSIM) index = 0.975/0.991/0.988 for MOLED/METMOLED-2/METMOLED-3, hyphenated number denotes the number of echo-trains), physical phantom (the slope of linear fitting with reference T2 map = 1.047/1.017/1.006 for MOLED/METMOLED-2/METMOLED-3), and human brain (Pearson's correlation coefficient (PCC) = 0.9581/0.9760/0.9900 for MOLED/METMOLED-2/METMOLED-3) demonstrated that the METMOLED improved the quantitative accuracy and the tissue details in contrast to the MOLED. These improvements were more pronounced in tissues with large T2 and in application scenarios with high temporal resolution (PCC = 0.8692/0.9465/0.9743 for MOLED/METMOLED-2/METMOLED-3). Moreover, the METMOLED could rectify the signal deviations induced by the non-ideal slice profiles of refocusing pulses without additional measurements. A preliminary measurement also demonstrated that the METMOLED is highly repeatable (mean coefficient of variation (CV) = 1.65%). CONCLUSIONS: METMOLED breaks the restriction of echo-train length to TE and implements unbiased T2 estimates in an extensive range. Furthermore, it corrects the effect of refocusing pulse inaccuracy without additional measurements or signal post-processing, thus retaining its single-shot characteristic. This technique would be beneficial for accurate T2 quantification.

12.
Front Plant Sci ; 13: 851151, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646042

RESUMO

Hybridization has fascinated biologists in recent centuries for its evolutionary importance, especially in plants. Hybrid zones are commonly located in regions across environmental gradients due to more opportunities to contact and ecological heterogeneity. For aquatic taxa, intrazonal character makes broad overlapping regions in intermediate environments between related species. However, we have limited information on the hybridization pattern of aquatic taxa in alpines, especially submerged macrophytes. In this study, we aimed to test the hypotheses that niche overlap and hybridization might be extensive in related aquatic plants across an altitudinal gradient. We evaluated the niche overlap in three related species pairs on the Qinghai-Tibetan Plateau and assessed the spatial pattern of hybrid populations. Obvious niche overlap and common hybridization were revealed in all three pairs of related aquatic plants. The plateau edge and river basins were broad areas for the sympatry of divergent taxa, where a large proportion of hybrid populations occurred. Hybrids are also discretely distributed in diverse habitats on the plateau. Differences in the extent of niche overlap, genetic incompatibility and phylogeographic history might lead to variation differences in hybridization patterns among the three species pairs. Our results suggested that plateau areas are a hotspot for ecologically divergent aquatic species to contact and mate and implied that hybridization may be important for the freshwater biodiversity of highlands.

13.
Soft Matter ; 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35703347

RESUMO

Animals have developed various drinking strategies in capturing liquid to feed or to stay hydrated. In contrast with most animals, honey bees Apis mellifera that capture nectar with their tongue, can deliberately switch between sucking and lapping methods. They preferentially suck diluted nectar whereas they are prone to lap concentrated nectar. In vivo observations have shown that bees select the feeding method yielding the highest efficiency at a given sugar concentration. In this combined experimental and theoretical investigation, we propose two physical models for suction and lapping mode of capture that explain the transition between these two feeding strategy. The critical viscosity, µ*, at which the transition occurs, is derived from these models, and agrees well with in vivo measurements. The trade-off mechanism of honey bee sucking and lapping may further inspire microfluidics devices with higher capability of transporting liquids across a large range of viscosities.

14.
Adv Mater ; : e2200671, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732070

RESUMO

Small-scale soft robots have been attracting increasing interest for visible and potential applications owing to their safety and tolerance resulting from their intrinsic soft bodies or compliant structures. However, it is not sufficient that the soft bodies merely provide support or system protection. More importantly, to meet the increasing demands of controllable operation and real-time feedback in unstructured/complicated scenarios, these robots are required to perform simplex and multimodal functionalities for sensing, communicating and interacting with external environments during large or dynamic deformation with the risk of mismatch or delamination. Challenges are encountered during fabrication and integration, including the selection and fabrication of composite/materials and structures, integration of active/passive functional modules with robust interfaces, particularly with highly deformable soft/stretchable bodies. In this review, methods and strategies of fabricating structural soft bodies and integrating them with functional modules for developing small-scale soft robots are investigated. Utilizing templating, 3D printing, transfer printing and swelling, small-scale soft robots can be endowed with several perceptual capabilities corresponding to diverse stimulus, such as light, heat, magnetism and force. The integration of sensing and functionalities effectively enhances the agility, adaptability and universality of soft robots when applied in various fields, including smart manufacturing, medical surgery, biomimetic and other interdisciplinary sciences. This article is protected by copyright. All rights reserved.

15.
Genes (Basel) ; 13(5)2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35627215

RESUMO

Traditional breeding strategies mainly focus on the evaluation of trait performance, but pay less attention to the changing genetic background. A comprehensive understanding of the genetic diversity of germplasms is crucial for the deliberate improvement of specific traits. A collection of 154 highland rice varieties were collected as the initial genetic resource in our breeding program to improve the pathogen resistance and eating and cooking qualities. These varieties were analyzed using a whole-genome SNP array and were clustered into three groups. Further analysis revealed that the favorable alleles of pathogen resistance genes are mostly absent in our collected varieties. However, it showed that most varieties possess favorable alleles of Waxy (Wx) and ALKALI DEGENERATION (ALK), which are able to enhance the eating and cooking qualities. Moreover, only about one fifth of all varieties harbors favorable the allele of fragrance gene Betainealdehyde dehydrogenase (BADH2). Together, these results give an overall view of the genetic constitution of the target traits, which provide useful information for future genetic improvement in breeding practices.


Assuntos
Oryza , Alelos , Testes Genéticos , Oryza/genética , Fenótipo , Melhoramento Vegetal
16.
Soft Robot ; 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35584255

RESUMO

The increasing demand for grasping diverse objects in unstructured environments poses severe challenges to the existing soft/rigid robotic fingers due to the issues in balancing force, compliance, and stability, and hence has given birth to several hybrid designs. These hybrid designs utilize the advantages of rigid and soft structures and show better performance, but they are still suffering from narrow output force range, limited compliance, and rarely reported stability. Owing to its rigid-soft coupling structure with flexible switched multiple poses, human finger, as an excellent hybrid design, shows wide-range output force, excellent compliance, and stability. Inspired by human finger, we propose a hybrid finger with multiple modes and poses, coupled by a soft actuator (SA) and a rigid actuator (RA) in parallel. The multiple actuation modes formed by a pneumatic-based rigid-soft collaborative strategy can selectively enable the RA's high force and SA's softness, whereas the multiple poses derived from the specially designed underactuated RA skeleton can be flexibly switched with tasks, thus achieving high compliance. Such hybrid fingers also proved to be highly stable under external stimuli or gravity. Furthermore, we modularize and configure these fingers into a series of grippers with excellent grasping performance, for example, wide graspable object range (diverse from 0.1 g potato chips to 27 kg dumbbells for a 420 g two-finger gripper), high compliance (tolerate objects with 94% gripper span size and 4 cm offset), and high stability. Our study highlights the potential of fusing rigid-soft technologies for robot development, and potentially impacts future bionics and high-performance robot development.

17.
Artigo em Inglês | MEDLINE | ID: mdl-35543426

RESUMO

Biomass-based adhesives have attracted much attention due to their eco-friendly, sustainable characteristics compared to formaldehyde-based adhesives; however, their low bonding strength and water resistance restrict their application. Thus, developing a high-performance biomass-based adhesive with excellent bonding strength and water resistance is necessary. In this work, a fully biomass-based citric acid-glucose (CAG) adhesive was produced by the esterification reaction of glucose and citric acid, which was validated by Fourier transform infrared (FT-IR), 13C nuclear magnetic resonance (13C NMR), and liquid chromatography-mass spectrometry (LC-MS). Furthermore, the properties of the CAG adhesive were tuned considering the effects of reaction time and molar ratio of citric acid/glucose (CA/G). It was revealed that increasing the molar ratio of CA/G is more advantageous to improve the shear strength and water resistance of plywood than the reaction time. The dry and wet strengths of plywood bonded by the CAG adhesive can reach the standard requirement (≥0.7 MPa) when the molar ratios of CA/G were more than 0.6 and the reaction time was 1 h. These results were better than those bonded by the urea-formaldehyde (UF) resin. Therefore, this green adhesive shows great potential to replace the existing industrial UF resin adhesives.

18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(5): 587-591, 2022 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-35570633

RESUMO

Objective: To investigate the effectiveness of disc reduction and anchorage in treatment of diacapitular condylar fracture with disc displacement. Methods: Between June 2019 and June 2021, 20 patients (27 sides) with diacapitular condylar fractures with disc displacement were treated with disc reduction and anchorage combined with internal fixation. There were 15 males and 5 females with a median age of 40 years (range, 8-65 years). The fractures were caused by falling from height in 3 cases, traffic accident in 3 cases, and falling in 14 cases. Among them, there were 13 cases of unilateral fracture and 7 cases of bilateral fractures. Five sides were type A fractures and 22 sides were type B. There were 14 simple diacapitular condylar fractures, 12 diacapitular condylar fractures combined with mandibular chin fractures, and 1 diacapitular condylar fracture combined with mandibular angle fracture. The maximum opening was 5-20 mm (mean, 9.7 mm). The time from injury to operation was 4-20 days, with an average of 11.6 days. The postoperative imaging examination was performed to evaluate the reduction of fracture and disc. The maximum opening at 6 months after operation was recorded, and the clinical dysfunction index (Di) of Helkimo index was used to evaluate the temporomandibular joint function. Results: All incisions healed by first intention. All 20 patients were followed up 6-10 months (mean, 8 months). Postoperative imaging examination showed that 27 fractures were well reduced, of which 26 were anatomically reduced and 1 was basically reduced; the reduction of the temporomandibular joint disc was excellent in 25 sides, good in 1 side, and poor in 1 side, and the effective rate of disc reduction and anchorage was 96.3%. The occlusion relationship of the patient was stable and basically reached the pre-injury level, the incision scar was hidden, and the mouth opening significantly improved when compared with the preoperative level. The maximum mouth opening was 32-40 mm (mean, 36.8 mm) at 6 months after operation. Maximum opening was more than 35 mm in 17 cases. At last follow-up, joint function reached Di 0 grade in 8 sides, DiⅠ grade in 18 sides, and DiⅡ grade in 1 side. After operation, 2 cases of opening deviation, 1 case of joint click, and 2 cases of temporary disappearance of frontal striae on affected side occurred, which recovered to normal after symptomatic treatment. Conclusion: For diacapitular condylar fractures with disc displacement, it is necessary to adopt disc reduction and anchorage at the same time of fracture reduction and internal fixation, which can achieve good clinical results.


Assuntos
Fraturas Mandibulares , Procedimentos Cirúrgicos Reconstrutivos , Adolescente , Adulto , Idoso , Criança , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Côndilo Mandibular/lesões , Côndilo Mandibular/cirurgia , Fraturas Mandibulares/diagnóstico , Fraturas Mandibulares/cirurgia , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
19.
Lasers Med Sci ; 37(7): 2889-2898, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35396621

RESUMO

Multiphoton microscopy (MPM), a high-resolution laser scanning technique, has been shown to provide detailed real-time information on fibrosis assessment in animal models. But the value of MPM in human histology, especially in heart tissue, has not been fully explored. We aimed to evaluate the association between myocardial fibrosis measured by MPM and that measured by histological staining in the transplanted human heart. One hundred and twenty samples of heart tissue were obtained from 20 patients consisting of 10 dilated cardiomyopathies (DCM) and 10 ischemic cardiomyopathies (ICM). MPM and picrosirius red staining were performed to quantify collagen volume fraction (CVF) in explanted hearts postoperatively. Cardiomyocyte and myocardial fibrosis could be clearly visualized by MPM. Although patients with ICM had significantly greater MPM-derived CVF than patients with DCM (25.33  ± 12.65 % vs. 19.82  ± 8.62 %, p = 0.006), there was a substantial overlap of CVF values between them. MPM-derived CVF was comparable to that derived from picrosirius red staining based on all samples (22.58 ± 11.13% vs. 21.19 ± 11.79%, p = 0.348), as well as in DCM samples and ICM samples. MPM-derived CVF was correlated strongly with the magnitude of staining-derived CVF in both all samples and DCM samples and ICM samples (r = 0.972, r = 0.963, r = 0.973, respectively; all p < 0.001). Intra- and inter-observer reproducibility for MPM-derived CVF and staining-derived CVF were 0.995, 0.989, 0.995, and 0.985, respectively. Our data demonstrated that MPM can provide a pathological-level assessment of myocardial microstructure in transplanted human heart.


Assuntos
Cardiomiopatias , Cardiomiopatia Dilatada , Animais , Cardiomiopatias/patologia , Cardiomiopatia Dilatada/patologia , Colágeno , Fibrose , Humanos , Microscopia , Miocárdio/patologia , Reprodutibilidade dos Testes
20.
Talanta ; 244: 123407, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35366513

RESUMO

The MnO2-TNTA composite electrodes were obtained through depositing MnO2 into TiO2 nanotube arrays (TNTA) by successive ionic layer adsorption reaction (SILAR) and subsequent hydrothermal method. The MnO2-TNTA nanocomposites were used as electrochemical sensors for the detection of hydrogen peroxide (H2O2). The preparation conditions of MnO2-TNTA electrodes and test conditions affect the electrochemical detection performance significantly. The optimal conditions are listed as follows: the number of SILAR cycles, 6 times; KMnO4 solution temperature, 50 °C; supporting electrolyte, 0.5 M NaOH. Under these conditions, the MnO2-TNTA electrode exhibits the best performance for detecting H2O2. The optimized MnO2-TNTA electrode has a minimum detection limit of 0.6 µM (S/N = 3) and a linear range of 5 µM âˆ¼ 13 mM, which is much superior to the previously-reported electrodes. Moreover, the optimized MnO2-TNTA electrode possesses high selectivity, excellent stability and good reproducibility in the detection of H2O2. When used in the determination of H2O2 content in actual samples including disinfectant and milk, it also shows good accuracy, ideal recovery (96.00% âˆ¼ 102.67%) and high precision (RSD < 4.0%).


Assuntos
Compostos de Manganês , Nanotubos , Técnicas Eletroquímicas/métodos , Eletrodos , Peróxido de Hidrogênio/química , Compostos de Manganês/química , Óxidos/química , Reprodutibilidade dos Testes , Titânio
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