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1.
Sensors (Basel) ; 24(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38610313

RESUMO

Simultaneous localisation and mapping (SLAM) is crucial in mobile robotics. Most visual SLAM systems assume that the environment is static. However, in real life, there are many dynamic objects, which affect the accuracy and robustness of these systems. To improve the performance of visual SLAM systems, this study proposes a dynamic visual SLAM (SEG-SLAM) system based on the orientated FAST and rotated BRIEF (ORB)-SLAM3 framework and you only look once (YOLO)v5 deep-learning method. First, based on the ORB-SLAM3 framework, the YOLOv5 deep-learning method is used to construct a fusion module for target detection and semantic segmentation. This module can effectively identify and extract prior information for obviously and potentially dynamic objects. Second, differentiated dynamic feature point rejection strategies are developed for different dynamic objects using the prior information, depth information, and epipolar geometry method. Thus, the localisation and mapping accuracy of the SEG-SLAM system is improved. Finally, the rejection results are fused with the depth information, and a static dense 3D mapping without dynamic objects is constructed using the Point Cloud Library. The SEG-SLAM system is evaluated using public TUM datasets and real-world scenarios. The proposed method is more accurate and robust than current dynamic visual SLAM algorithms.

2.
J Hazard Mater ; 468: 133699, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368680

RESUMO

Chlorine has been proven to promote the volatilization of heavy metals during sludge combustion. This work compared the migration of heavy metals with NaCl addition under different combustion modes at 900 â„ƒ. The combustion modes have less effect on the mineral phase of residues, but the volatilization and toxicity reduction of heavy metals were more pronounced under isothermal combustion. The mineral evolution, release of Cl, and migration of metals were dynamically tracked by the continuous sampling at different combustion time under isothermal combustion. It was found that the volatile matter and fixed carbon burned almost simultaneously, and the addition of NaCl promoted them. As combustion proceeded, the minerals gradually crystallized and the heavy metals were volatilized due to the direct and indirect chlorination. Meanwhile, the chlorination and volatilization of Zn was less than that of Pb due to its effective solidification by minerals. The combination of the adsorption by exposed char and solidification by sludge minerals influenced the dynamic leaching behavior of metals. These results will help understand the interactions between heavy metals, inorganic Cl, and Fe-Si-Al minerals during combustion, which will further help optimize the combustion strategy for both stabilization or enrichment of heavy metals when inorganic chlorine exists.

3.
J Hazard Mater ; 468: 133837, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38401216

RESUMO

The sound disposal of the ensuing heavy metal-rich plants can address the aftermath of phytoremediation. In this study, the first attempt was made to obtain heavy metals-free and phosphorus-rich biochar from phytoremediation residue (PR) by pyrolysis, and the effects of chlorinating agent type, chlorine dosage, and pyrolysis residence time on heavy metal removal, phosphorus (P) transformation, and biochar properties were investigated. The results showed that as chlorine dosage and pyrolysis residence time increased, added polyvinyl chloride (PVC) reduced the concentration of Zn in biochar to one-tenth of that in PR by intensified chlorination, where both Zn concentration (2727.50 mg/kg) and its leaching concentration (29.13 mg/L) met the utilization requirements, in which the acid-base property of biochar plays a key role in heavy metal leaching. Meanwhile, more than 90% of P in PR remained in biochar and the bioavailability of P in biochar enhanced with the decomposition of organic P to inorganic P, where the concentration of plant-availability P (Pnac) expanded from 1878.40 mg/kg in PR to 8454.00 mg/kg in biochar. This study demonstrated that heavy metal hyperaccumulator can be converted into heavy metal-free and phosphorus-rich biochar with promising applications, which provides new perspectives for the treatment of such hazardous wastes.


Assuntos
Metais Pesados , Fósforo , Cloro , Pirólise , Metais Pesados/química , Carvão Vegetal/química
4.
Sensors (Basel) ; 23(23)2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38067967

RESUMO

Simultaneous location and mapping (SLAM) technology is key in robot autonomous navigation. Most visual SLAM (VSLAM) algorithms for dynamic environments cannot achieve sufficient positioning accuracy and real-time performance simultaneously. When the dynamic object proportion is too high, the VSLAM algorithm will collapse. To solve the above problems, this paper proposes an indoor dynamic VSLAM algorithm called YDD-SLAM based on ORB-SLAM3, which introduces the YOLOv5 object detection algorithm and integrates deep information. Firstly, the objects detected by YOLOv5 are divided into eight subcategories according to their motion characteristics and depth values. Secondly, the depth ranges of the dynamic object and potentially dynamic object in the moving state in the scene are calculated. Simultaneously, the depth value of the feature point in the detection box is compared with that of the feature point in the detection box to determine whether the point is a dynamic feature point; if it is, the dynamic feature point is eliminated. Further, multiple feature point optimization strategies were developed for VSLAM in dynamic environments. A public data set and an actual dynamic scenario were used for testing. The accuracy of the proposed algorithm was significantly improved compared to that of ORB-SLAM3. This work provides a theoretical foundation for the practical application of a dynamic VSLAM algorithm.

5.
J Exp Clin Cancer Res ; 42(1): 331, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049865

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies and is characterized by reprogrammed metabolism. Ferroptosis, a programmed cell death dependent on iron, has emerged as a promising strategy for CRC treatment. Although small nucleolar RNAs are extensively involved in carcinogenesis, it is unclear if they regulate ferroptosis during CRC pathogenesis. METHODS: The dysregulated snoRNAs were identified using published sequencing data of CRC tissues. The expression of the candidate snoRNAs, host gene and target gene were assessed by real-time quantitative PCR (RT-qPCR), fluorescence in situ hybridization (FISH), immunohistochemistry (IHC) and western blots. The biological function of critical molecules was investigated using in vitro and in vivo strategies including Cell Counting Kit-8 (CCK8), colony formation assay, flow cytometry, Fe2+/Fe3+, GSH/GSSG and the xenograft mice models. The ribosomal activities were determined by polysome profiling and O-propargyl-puromycin (OP-Puro) assay. The proteomics was conducted to clarify the downstream targets and the underlying mechanisms were validated by IHC, Pearson correlation analysis, protein stability and rescue assays. The clinical significance of the snoRNA was explored using the Cox proportional hazard model, receiver operating characteristic (ROC) and survival analysis. RESULTS: Here, we investigated the SNORA56, which was elevated in CRC tissues and plasma, and correlated with CRC prognosis. SNORA56 deficiency in CRC impaired proliferation and triggered ferroptosis, resulting in reduced tumorigenesis. Mechanistically, SNORA56 mediated the pseudouridylation of 28 S rRNA at the U1664 site and promoted the translation of the catalytic subunit of glutamate cysteine ligase (GCLC), an indispensable rate-limiting enzyme in the biosynthesis of glutathione, which can inhibit ferroptosis by suppressing lipid peroxidation. CONCLUSIONS: Therefore, the SNORA56/28S rRNA/GCLC axis stimulates CRC progression by inhibiting the accumulation of cellular peroxides, and it may provide biomarker and therapeutic applications in CRC.


Assuntos
Neoplasias Colorretais , Ferroptose , Glutamato-Cisteína Ligase , RNA Nuclear Pequeno , Animais , Humanos , Camundongos , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Ferroptose/genética , Hibridização in Situ Fluorescente , RNA Ribossômico , RNA Nuclear Pequeno/genética
6.
Neurol Ther ; 12(5): 1777-1789, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37531028

RESUMO

INTRODUCTION: Based on real-world case data, this study intends to explore and analyze the impact of rescue conscious sedation (CS) on the clinical outcomes of patients with anterior circulation acute ischemic stroke (AIS) receiving mechanical thrombectomy (MT). METHODS: This retrospective study enrolled patients with anterior circulation AIS who received MT and were treated with either single local anesthesia (LA) or rescue CS during MT between January 2018 and October 2021. We used univariate and multivariate logistic regression methods to compare the impact of LA and CS on the clinical outcomes of patients with AIS who received MT, including the mRS at 90 days, the incidence of poststroke pneumonia (PSP), the incidence of symptomatic intracranial cerebral hemorrhage (sICH), and the mortality rate. RESULTS: We reviewed 314 patient cases with AIS who received MT. Of all patients, 164 met our search criteria. Eighty-nine patients received LA, and 75 patients received rescue CS. There was no significant difference between the two groups in the 90-day good prognosis (45.3% vs. 51.7%, p = 0.418) and mortality (17.3% vs. 22.5%, p = 0.414). Compared with the LA group, the incidence of postoperative pneumonia in the rescue CS group (44% vs. 25.8%, p = 0.015) was more significant. Multivariate stepwise logistic regression analysis revealed that intraoperative remedial CS was independently associated with PSP following MT. In a subgroup analysis, rescue CS was found to significantly increase the incidence of PSP in patients with dysphagia (OR = 7.307, 95% CI 2.144-24.906, p = 0.001). As the severity of the National Institutes of Health Stroke Scale (NIHSS) increased, intraoperative rescue CS was found to increase the risk of PSP (OR = 1.155, 95% CI 1.034-1.290, p = 0.011) by 5.1% compared to that of LA (OR = 1.104, 95% CI 1.013-1.204, p = 0.024). CONCLUSION: Compared to LA, rescue CS during MT does not significantly improve the 90 days of good prognosis and reduce the incidence of sICH and mortality in patients with anterior circulation AIS. However, it has a significantly increased risk of poststroke pneumonia (PSP), particularly in patients with dysphagia.

7.
Pract Radiat Oncol ; 13(6): 522-530, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37437806

RESUMO

PURPOSE: Tumor treating fields (TTFields) with concurrent radiation therapy (RT) might improve the outcome of patients with newly diagnosed glioblastoma. Several trials, including that conducted in our center, have allowed patients to wear TTFields during RT. We aimed to evaluate the setup uncertainty introduced by TTFields and calculate the planning target volume (PTV) margin for clinical reference. METHODS AND MATERIALS: We collected and analyzed 201 cone beam computed tomography images of 22 patients in our center. Patients with or without TTFields were divided into the control and TTFields groups. We evaluated the setup errors in 6 degrees of freedom and 3 degrees of freedom and the magnitudes in the 3-dimensional vectors. An estimated PTV margin for patients requiring nonimaging-guided RT was recommended. RESULTS: A significant difference was observed in the longitudinal axis between the TTFields and control groups (P < .05). These results were consistent with that of the intragroup comparison of the TTFields group. The position error of the longitudinal axis (from head to feet) was -0.51 ± 2.05 mm in the TTFields group. CONCLUSIONS: Wearing TTFields during RT increased the uncertainty, especially in the longitudinal axis, with a system error of 1.40 mm and a random error of 1.28 mm. Daily image guided RT for TTFields patients seems necessary. However, the recommended expansion margin of the PTV is 5 mm for patients requiring nonimage-guided RT to enhance the safety and efficacy of treatment.


Assuntos
Glioblastoma , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Humanos , Glioblastoma/radioterapia , Incerteza , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Planejamento da Radioterapia Assistida por Computador/métodos
8.
Sci Total Environ ; 858(Pt 2): 159895, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336052

RESUMO

Si/Al-based adsorbents are effective adsorbents for capturing heavy metals in incineration flue gases at high temperatures in the furnace. In this work, the adsorption characteristics and adsorption mechanisms of Si/Al-based adsorbents for lead and cadmium vapors were studied using a combination of experimental and density functional theory (DFT) calculations. The trapping performance of a series of Si/Al-based adsorbents for Pb and Cd vapors was investigated using a self-designed gas-solid two-phase rapid adsorption experimental system. The results showed that kaolinite and montmorillonite exhibited better heavy metal adsorption capacity than SiO2 and Al2O3, and were significantly stronger for Pb than for Cd. Chemisorption dominated the capture of Pb/Cd by Si/Al-based adsorbents at high temperatures. The results of DFT calculations indicated that the chemisorption mechanisms dominated the adsorption of Pb and Cd species on the metakaolinite (001) surface, and the adsorption energy of Pb species on the metakaolinite surface was greater than that of Cd species. The exposed O atoms and unsaturated Al atoms of metakaolinite (001) surface were effective adsorption active sites for heavy metals and their chlorides. In the adsorption reaction, the binding of Pb/Cd atoms and surface exposed O sites, as well as the strong interaction between Cl and unsaturated Al atoms, were responsible for the capture of Pb and Cd chlorides by metakaolinite.


Assuntos
Incineração , Metais Pesados , Cádmio/química , Adsorção , Chumbo , Dióxido de Silício , Cloretos , Gases/química , Metais Pesados/química , Modelos Teóricos
9.
Technol Health Care ; 31(2): 459-469, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36278364

RESUMO

BACKGROUND: The limited number of hip prostheses users makes it less feasible to conduct amputee tests for prosthesis development in the clinic, which restricts the development efficiency of the intelligent prostheses. OBJECTIVE: This study proposes a hip disarticulation prostheses test system (HDPTS) to supplement the amputee tests for hip disarticulation prosthesis (HDP) evaluation, which would potentially facilitate the prosthesis evaluation safety and development efficiency. METHODS: The hip trajectory of an individual with normal gait was acquired and reproduced by calculating the corresponding movement joint angle of a manipulator. Then, an HDP was fit on an amputee and on the HDPTS respectively to obtain the hip and knee joint angles of the HDP during walking. Comparing the root mean square error (RMSE) of the expected and planned trajectory, the joint angles between the amputee test and HDPTS test, to verify the feasibility and accuracy of the HDPTS for prosthesis evaluation. RESULTS: The RMSE between the expected and planned trajectory value was less than 1.20 mm (< 0.19%). The RMSE of the joint angles between the amputee test and HDPTS test were 2.18∘ (1.8%) and 3.13∘ (5.92%) for hip and knee joint respectively. CONCLUSION: The HDPTS was found accurate in hip trajectory reproduction and feasible in gait simulation for the prosthesis evaluation, which could potentially supplement the amputee test for prosthesis design thus improving prosthesis test safety and development efficiency.


Assuntos
Amputados , Membros Artificiais , Prótese de Quadril , Humanos , Desarticulação , Prótese de Quadril/efeitos adversos , Marcha , Caminhada , Articulação do Joelho , Fenômenos Biomecânicos , Desenho de Prótese
11.
Front Immunol ; 13: 954801, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248825

RESUMO

SARS-CoV-2 and its mutant strains continue to rapidly spread with high infection and fatality. Large-scale SARS-CoV-2 vaccination provides an important guarantee for effective resistance to existing or mutated SARS-CoV-2 virus infection. However, whether the host metabolite levels respond to SARS-CoV-2 vaccine-influenced host immunity remains unclear. To help delineate the serum metabolome profile of SARS-CoV-2 vaccinated volunteers and determine that the metabolites tightly respond to host immune antibodies and cytokines, in this study, a total of 59 sera samples were collected from 30 individuals before SARS-CoV-2 vaccination and from 29 COVID-19 vaccines 2 weeks after the two-dose vaccination. Next, untargeted metabolomics was performed and a distinct metabolic composition was revealed between the pre-vaccination (VB) group and two-dose vaccination (SV) group by partial least squares-discriminant and principal component analyses. Based on the criteria: FDR < 0.05, absolute log2 fold change greater than 0.25, and VIP >1, we found that L-glutamic acid, gamma-aminobutyric acid (GABA), succinic acid, and taurine showed increasing trends from SV to VB. Furthermore, SV-associated metabolites were mainly annotated to butanoate metabolism and glutamate metabolism pathways. Moreover, two metabolite biomarkers classified SV from VB individuals with an area under the curve (AUC) of 0.96. Correlation analysis identified a positive association between four metabolites enriched in glutamate metabolism and serum antibodies in relation to IgG, IgM, and IgA. These results suggest that the contents of gamma-aminobutyric acid and indole in serum could be applied as biomarkers in distinguishing vaccinated volunteers from the unvaccinated. What's more, metabolites such as GABA and taurine may serve as a metabolic target for adjuvant vaccines to boost the ability of the individuals to improve immunity.


Assuntos
COVID-19 , Vacinas Virais , Biomarcadores , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Citocinas , Ácido Glutâmico , Humanos , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Indóis , Metabolômica , SARS-CoV-2 , Ácido Succínico , Taurina , Vacinação , Ácido gama-Aminobutírico
12.
Materials (Basel) ; 15(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35744254

RESUMO

Cracking is one of the main problems in concrete structures and is affected by various parameters. The step-by-step laboratory method, which includes casting specimens, curing for a certain period, and testing, remains a source of worry in terms of cost and time. Novel machine learning methods for anticipating the behavior of raw materials on the ultimate output of concrete are being introduced to address the difficulties outlined above such as the excessive consumption of time and money. This work estimates the splitting-tensile strength of concrete containing recycled coarse aggregate (RCA) using artificial intelligence methods considering nine input parameters and 154 mixes. One individual machine learning algorithm (support vector machine) and three ensembled machine learning algorithms (AdaBoost, Bagging, and random forest) are considered. Additionally, a post hoc model-agnostic method named SHapley Additive exPlanations (SHAP) was performed to study the influence of raw ingredients on the splitting-tensile strength. The model's performance was assessed using the coefficient of determination (R2), root mean square error (RMSE), and mean absolute error (MAE). Then, the model's performance was validated using k-fold cross-validation. The random forest model, with an R2 of 0.96, outperformed the AdaBoost models. The random forest models with greater R2 and lower error (RMSE = 0.49) had superior performance. It was revealed from the SHAP analysis that the cement content had the highest positive influence on the splitting-tensile strength of the recycled aggregate concrete and the primary contact of cement is with water. The feature interaction plot shows that high water content has a negative impact on the recycled aggregate concrete (RAC) splitting-tensile strength, but the increased cement content had a beneficial effect.

13.
Sci Total Environ ; 813: 151865, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-34813819

RESUMO

Developing of effective photocatalysts is of great significance for realizing photocatalytic environment purification. Herein, an interfacial bent bands and internal electric field modulated CeO2/ZnIn2S4 Z-scheme heterojunction for photocatalytic Hg0 oxidation. It is found that the charge transfer mechanism of Z-scheme was driven by the interfacial bent bands and internal electric field, which was confirmed by electrochemical measurements, electron spin paramagnetic resonance spectroscopy and density functional theory calculations. Moreover, the (110) dominant CeO2 nanorods partially converted Ce4+ to Ce3+ and formed oxygen vacancies, and as an electron mediator in Z-scheme systems to further facilitate charge transfer process and molecular oxygen activation. Under the strong synergistic effect between the large specific surface area, Z-scheme heterojunction and oxygen vacancies, the optimized photocatalyst exhibits 86.7% of photocatalytic removal efficiency. This work provides Z-scheme heterojunction photocatalyst design perspective for photocatalytic air purification.

14.
J Hazard Mater ; 419: 126436, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34216967

RESUMO

Nanosized ZnIn2S4 supported on facet-engineered CeO2 nanorods were prepared by solvothermal method to effectively capture gaseous elemental mercury from flue gas. The CeO2/ZnIn2S4 sorbent exhibited excellent mercury removal performance (>90%) in a wide temperature range from 60 to 240 â„ƒ and showed much higher mercury adsorption capacity than pure CeO2 due to the enlarged specific surface area and abundant active oxygen and sulfur sites on the surface. It was found that CeO2/ZnIn2S4 has good resistance to SO2, NO and H2O. At the optimal 120 â„ƒ, the equilibrium Hg0 adsorption capacity of CeO2/ZnIn2S4 can reach 19.172 mg/g, which is superior to the reported series of benchmark materials. X-ray photoelectron spectroscopy and temperature programmed desorption of mercury confirmed that the adsorbed mercury existed on the surface as HgO and HgS, indicating that catalytic oxidation and chemisorption occurred on the surface of the adsorbent. The adsorption energy of Hg0 on the CeO2 (110) and ZnIn2S4 (110) surfaces calculated with density functional theory (DFT), further confirms that the surface activated oxygen and sulfur sites are the most stable adsorption sites. Furthermore, the good regeneration capability of CeO2/ZnIn2S4 makes it more promising for Hg0 capture in practical applications.

15.
J Colloid Interface Sci ; 587: 402-416, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33370662

RESUMO

Oxygen vacancy-rich CeO2/BiOBr was prepared via solvothermal method combined with rGO to design a Z-scheme heterojunction, which was used for photocatalytic oxidation of gaseous elemental mercury. The Z-scheme heterojunction constructed by interface engineering significantly promotes charge carriers transfer at the interface. Moreover, the surface oxygen vacancies and Ce3+/Ce4+ redox centers tend to capture electrons to accelerate the Z-scheme path of charge transfer to maintain efficient redox performance and facilitate molecular oxygen activation to boost photocatalytic removal of Hg0. The collaboration of oxygen vacancies, Ce3+/Ce4+ and heterojunction enhances the photocatalytic oxidation activity, which achieves a removal efficiency of 76.53%, which is 1.29 times that of BiOBr and 1.91 times that of CeO2. The effect of actual flue gas components (SO2, NO and HCl) on the performance of photocatalytic Hg0 removal was further investigated. Combined with DFT theoretical calculations, the photocatalytic reaction mechanism of Z-scheme heterojunction with oxygen vacancies-rich was proposed. It provides a feasible strategy for the development of high-efficiency Z-scheme heterojunction photocatalytic system for environmental purification.

16.
J Colloid Interface Sci ; 562: 429-443, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-31791698

RESUMO

A new ternary composite BiOIO3/MoS2/C500 was prepared via sol-gel and hydrothermal method. The energy bands, surface structures and optical properties of the as-prepared samples were characterized by XRD, SEM, TEM, UV-vis DRS, BET, XPS, PL, ESR and electrochemical measurement. The density functional theory (DFT) was adopted to explore the capability as well. It is discovered that BiOIO3/MoS2/C500 possesses excellent Z-scheme heterostructure for separating photogenerated electron-hole pairs mainly provided by BiOIO3/MoS2, and large specific surface area as charge carriers transfer channel mainly provided by C500, which can accelerate charges to transfer to the surface reaction area for photocatalytic oxidation. Then, the ternary catalyst was utilized to remove gas-phase Hg0 including its oxidation product, and possessed the highest removal efficiency of 78.32%, which is much higher than that of its pure component. Meanwhile, the photocatalytic activity of ternary catalyst are of high stability, and the product after the reaction is HgO and can be adsorbed on BiOIO3/MoS2/C500, which is detected by high resolution XPS. The loading manner provides a new vision for both photocatalysis and adsorption.

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