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1.
Materials (Basel) ; 17(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38730933

RESUMEN

High-nickel ternary materials are currently the most promising lithium battery cathode materials due to their development and application potential. Nevertheless, these materials encounter challenges like cation mixing, lattice oxygen loss, interfacial reactions, and microcracks. These issues are exacerbated at high voltages, compromising their cyclic stability and safety. In this study, we successfully prepared Nb5+-doped high-nickel ternary cathode materials via a high-temperature solid-phase method. We investigated the impact of Nb5+ doping on the microstructure and electrochemical properties of LiNi0.88Co0.05Mn0.07O2 ternary cathode materials by varying the amount of Nb2O5 added. The experimental results suggest that Nb5+ doping does not alter the crystal structure but modifies the particle morphology, yielding radially distributed, elongated, rod-like structures. This morphology effectively mitigates the anisotropic volume changes during cycling, thereby bolstering the material's cyclic stability. The material exhibits a discharge capacity of 224.4 mAh g-1 at 0.1C and 200.3 mAh g-1 at 1C, within a voltage range of 2.7 V-4.5 V. Following 100 cycles at 1C, the capacity retention rate maintains a high level of 92.9%, highlighting the material's remarkable capacity retention and cyclic stability under high-voltage conditions. The enhancement of cyclic stability is primarily due to the synergistic effects caused by Nb5+ doping. Nb5+ modifies the particle morphology, thereby mitigating the formation of microcracks. The formation of high-energy Nb-O bonds prevents oxygen precipitation at high voltages, minimizes the irreversibility of the H2-H3 phase transition, and thereby enhances the stability of the composite material at high voltages.

2.
Molecules ; 29(9)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38731590

RESUMEN

Waterborne polyurethane, renowned for its lightweight properties, excellent insulation capabilities, and corrosion resistance, has found extensive application in fields such as construction, automotive, leather, and thermal insulation. Nevertheless, during operational usage, waterborne polyurethane materials, akin to other polymeric substances, are susceptible to oxidative aging manifestations like yellowing, cracking, and diminished mechanical performance, significantly curtailing their utility. Consequently, the synthesis of yellowing-resistant polyurethane assumes pivotal significance. This study integrates dynamic reversible reactions into the synthesis process of polyurethane by introducing the dynamic reversible compound 2-hydroxyethyl disulfide as a chain extender, alongside the incorporation of a UV absorber to enhance the polyurethane's resistance to yellowing. When the disulfide bonds absorb heat, they undergo cleavage, yielding thiols that spontaneously recombine into disulfide bonds at ambient temperatures, allowing for the continuous breaking and reformation of disulfide bonds to absorb heat. Concurrently, in collaboration with the UV absorber, the detrimental effects of ultraviolet radiation on the polyurethane material are mitigated, thereby augmenting its resistance to yellowing. This study scrutinizes the positioning of UV absorber addition, the quantity of UV absorber, and the molar ratio of 1,4-butanediol to 2-hydroxyethyl disulfide, characterizing the functional groups of polyurethane through infrared and Raman spectroscopy. It is observed that the successful preparation of yellowing-resistant polyurethane is achieved, and evaluations on the modified polyurethane through color difference, tensile, and centrifugal tests reveal that the optimal yellowing resistance is attained by adding a UV absorber at a mass fraction of 1% to 3% prior to chain extension, resulting in a color change grade of 2, denoting slight discoloration. Simultaneously, the other properties of polyurethane exhibit relative stability. Notably, when the molar ratio of 1,4-butanediol to 2-hydroxyethyl disulfide is 3:2, the overall performance of the polyurethane remains stable, with exceptional yellowing resistance capabilities attaining a color change grade of 2.

3.
Plant Physiol Biochem ; 211: 108708, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38733938

RESUMEN

S-Adenosyl-L-methionine (SAM) is widely involved in plant growth, development, and abiotic stress response. SAM synthetase (SAMS) is the key enzyme that catalyzes the synthesis of SAM from methionine and ATP. However, the SAMS gene family has not been identified and their functions have not been characterized in most Cucurbitaceae plants. Here, a total of 30 SAMS genes were identified in nine Cucurbitaceae species and they were categorized into 3 subfamilies. Physicochemical properties and gene structure analysis showed that the SAMS protein members are tightly conserved. Further analysis of the cis-regulatory elements (CREs) of SAMS genes' promoter implied their potential roles in stress tolerance. To further understand the molecular functions of SAMS genes, watermelon SAMSs (ClSAMSs) were chosen to analyze the expression patterns in different tissues and under various abiotic stress and hormone responses. Among the investigated genes, ClSAMS1 expression was observed in all tissues and found to be up-regulated by abiotic stresses including salt, cold and drought treatments as well as exogenous hormone treatments including ETH, SA, MeJA and ABA. Furthermore, knockdown of ClSAMS1 via virus-induced gene silencing (VIGS) decreased SAM contents in watermelon seedings. The pTRSV2-ClSAMS1 plants showed reduced susceptibility to drought, cold and NaCl stress, indicating a positive role of ClSAMS1 in abiotic stresses tolerance. Those results provided candidate SAMS genes to regulate plant resistance against abiotic stresses in Cucurbitaceae plants.

4.
Phys Rev E ; 109(4-1): 044118, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38755899

RESUMEN

Whether the strong coupling to thermal baths can improve the performance of quantum thermal machines remains an open issue under active debate. Here we revisit quantum thermal machines operating with the quasistatic Carnot cycle and aim to unveil the role of strong coupling in maximum efficiency. Our analysis builds upon definitions of excess work and heat derived from an exact formulation of the first law of thermodynamics for the working substance, which captures the non-Gibbsian thermal equilibrium state that emerges at strong couplings during quasistatic isothermal processes. These excess definitions differ from conventional ones by an energetic cost for maintaining the non-Gibbsian characteristics. With this distinction, we point out that one can introduce two different yet thermodynamically allowed definitions for efficiency of both the heat engine and refrigerator modes. We dub them excess and hybrid definitions, which differ in the way of defining the gain for the thermal machines at strong couplings by either just analyzing the energetics of the working substance or instead evaluating the performance from an external system upon which the thermal machine acts, respectively. We analytically demonstrate that the excess definition predicts that the Carnot limit remains the upper bound for both operation modes at strong couplings, whereas the hybrid one reveals that strong coupling can suppress the maximum efficiency rendering the Carnot limit unattainable. These seemingly incompatible predictions thus indicate that it is imperative to first gauge the definition for efficiency before elucidating the exact role of strong coupling, thereby shedding light on the ongoing investigation on strong-coupling quantum thermal machines.

5.
J Am Chem Soc ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713009

RESUMEN

Unveiling innovative mechanisms to design new highly efficient fluorescent materials and, thereby, fabricate high-performance organic light-emitting diodes (OLEDs) is a concerted endeavor in both academic and industrial circles. Polycyclic aromatic hydrocarbons (PAHs) have been widely used as fluorescent emitters in blue OLEDs, but device performances are far from satisfactory. In response, we propose the concept of "nitrogen effects" endowed by doping electron-withdrawing nitrogen atoms into PAH fluorescence emitters. The presence of the n orbital on the imine nitrogen is conducive to promoting electron coupling, which leads to increased molar absorptivity and an accelerated radiative decay rate of emitters, thereby facilitating the Förster energy transfer (FET) process in the OLEDs. Additionally, electronically withdrawing nitrogen atoms enhances host-guest interactions, thereby positively affecting the FET process and the horizontal orientation factor of the emitting layer. To validate the "nitrogen effects" concept, cobalt-catalyzed multiple C-H annulation has been utilized to incorporate alkynes into the imine-based frameworks, which enables various imine-embedded PAH (IE-PAH) fluorescence emitters. The cyclization demonstrates notable regioselectivity, thereby offering a practical tool to precisely introduce peripheral groups at desired positions with bulky alkyl units positioned adjacent to the nitrogen atoms, which were previously beyond reach through the Friedel-Crafts reaction. Blue OLEDs fabricated with IE-PAHs exhibit outstanding performance with a maximum external quantum efficiency (EQEmax) of 32.7%. This achievement sets a groundbreaking record for conventional blue PAH-based fluorescent emitters, which have an EQEmax of 24.0%.

6.
J Org Chem ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38752832

RESUMEN

Methods for regioselective N-trideuteromethylation of tautomeric polyaza heterocycles are highly sought-after. Disclosed herein is an N-trideuterated methylation reaction of imidazoles and pyrazoles with high regioselectivity and deuterium purity using easily available CF3SO3CD3 as the -CD3 source. This method enables the easy synthesis of important deuterium-labeled azoles, including dimetridazole-d3, ipronidazole-d3, hydroxy dimetridazole-d3, and ronidazole-d3.

7.
Cancer Control ; 31: 10732748241250208, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716756

RESUMEN

Nasopharyngeal Carcinoma (NC) refers to the malignant tumor that occurs at the top and side walls of the nasopharyngeal cavity. The NC incidence rate always dominates the first among the malignant tumors of the ear, nose and throat, and mainly occurs in Asia. NC cases are mainly concentrated in southern provinces in China, with about 4 million existing NC. With the pollution of environment and pickled diet, and the increase of life pressure, the domestic NC incidence rate has reached 4.5-6.5/100000 and is increasing year by year. It was reported that the known main causes of NC include hereditary factor, genetic mutations, and EB virus infection, common clinical symptoms of NC include nasal congestion, bloody mucus, etc. About 90% of NC is highly sensitive to radiotherapy which is regard as the preferred treatment method; However, for NC with lower differentiation, larger volume, and recurrence after treatment, surgical resection and local protons and heavy ions therapy are also indispensable means. According to reports, the subtle heterogeneity and diversity exists in some NC, with about 80% of NC undergone radiotherapy and about 25% experienced recurrence and death within five years after radiotherapy in China. Therefore, screening the NC population with suspected recurrence after concurrent chemoradiotherapy may improve survival rates in current clinical decision-making.


NC is one of the prevalent malignancies of the head and neck region with poor prognosis. The aim of this study is to establish a predictive model for assessing NC prognosis using clinical and MR radiomics data.


Asunto(s)
Quimioradioterapia , Imagen por Resonancia Magnética , Neoplasias Nasofaríngeas , Recurrencia Local de Neoplasia , Humanos , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/diagnóstico por imagen , Quimioradioterapia/métodos , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Estudios Retrospectivos , Masculino , Persona de Mediana Edad , Imagen por Resonancia Magnética/métodos , Femenino , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/diagnóstico por imagen , Adulto , China/epidemiología , Metástasis de la Neoplasia , Anciano , Radiómica
8.
Front Nutr ; 11: 1352938, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38559779

RESUMEN

Development of simple and reliable sensor for detecting vitamin content is of great significance for guiding human nutrition metabolism, overseeing the quality of food or drugs, and advancing the treatment of related diseases. In this work, a simple electrochemical sensor was conveniently fabricated by modification a carbon electrode with vertically-ordered mesoporous silica film (VMSF), enabling highly sensitive electrochemical detection of vitamin B2 (VB2) based on the dual enrichment of the analyte by the supporting electrode and nanochannels. The widely used glassy carbon electrode (GCE), was preactivated using simple electrochemical polarization, The resulting preactivated GCE (p-GCE) exhibited improved potential resolution ability and enhanced peak current of VB2. Stable modification of VMSF on p-GCE (VMSF/p-GCE) was achieved without introducing another binding layer. The dual enrichment effect of the supporting p-GCE and nanochannels facilitated sensitive detection of VB2, with a linear concentration ranged from 20 nM to 7 µM and from 7 µM to 20 µM. The limit of detection (LOD), determined based on a signal-to-noise ratio of three (S/N = 3), was found to be 11 nM. The modification of ultra-small nanochannels of VMSF endowed VMSF/p-GCE with excellent anti-interference and anti-fouling performance, along with high stability. The constructed sensor demonstrated the capability to achieve direct electrochemical detection of VB2 in turbid samples including milk and leachate of compound vitamin B tablet without the need for complex sample pretreatment. The fabricated electrochemical can be easily regenerated and has high reusability. The advantages of simple preparation, high detection performance, and good regeneration endow the constructed electrochemical sensor with great potential for direct detection of small molecule in complex samples.

9.
Future Microbiol ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38629914

RESUMEN

Background: Gut microbiota is pivotal in tumor occurrence and development, and there is a close relationship between Akkermansia muciniphila (AKK) and cancer immunotherapy. Methods: The effects of AKK and its outer membrane proteins on gastric cancer (GC) were evaluated in vitro and in vivo using cell counting kit-8 assay, flow cytometry, western blotting, ELISA, immunohistochemistry and immunofluorescence. Results: AKK outer membrane protein facilitated apoptosis of GC cells and exerted an immunostimulatory effect (by promoting M1 polarization of macrophages, enhancing expression of cytotoxic T-lymphocyte-related cytokines and suppressing that of Treg-related cytokines). Additionally, AKK and its formulation could inhibit tumor growth of GC and enhance the infiltration of immune cells in tumor tissues. Conclusion: AKK could improve GC treatment by modulating the immune microenvironment.


Akkermansia muciniphila (AKK) is a type of bacteria found in the human gut that is good for the immune system. We wanted to investigate the effect of AKK on cancer. We extracted a protein from AKK called Amuc. AKK and Amuc inhibited the growth of stomach cancer by encouraging the action of immune cells. AKK may therefore be able to treat stomach cancer.

10.
Dalton Trans ; 53(19): 8093-8104, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38685829

RESUMEN

The photocatalytic technique has been widely recognized as a feasible technological route for sustainable energy conversion of solar energy into chemical energy. Photocatalysts play a vital role in the whole catalytic process. In particular, organolead halide perovskites have become emerging photocatalysts, owing to their precisely tunable light absorption range, high carrier diffusion mobility, and longer carrier lifetime and diffusion length. Nevertheless, their intrinsic structural instability and high carrier recombination rate are the major bottlenecks for further development in photocatalytic applications. This Frontier is focused on the recent research about the instability mechanism of organolead halide perovskites. Then, we summarize the recently developed strategies to improve the structural stability and photocatalytic activity of organolead halide materials, with an emphasis on the construction of organolead halide crystalline catalysts with high intrinsic structural stability. Finally, an outlook and challenges of organometal halide photocatalysts are presented, demonstrating the irreplaceable role of this class of emergent materials in the field of photo-energy conversion.

11.
Nano Lett ; 24(20): 6192-6200, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38666542

RESUMEN

Creating artificial synapses that can interact with biological neural systems is critical for developing advanced intelligent systems. However, there are still many difficulties, including device morphology and fluid selection. Based on Micro-Electro-Mechanical System technologies, we utilized two immiscible electrolytes to form a liquid/liquid interface at the tip of a funnel nanochannel, effectively enabling a wafer-level fabrication, interactions between multiple information carriers, and electron-to-chemical signal transitions. The distinctive ionic transport properties successfully achieved a hysteresis in ionic transport, resulting in adjustable multistage conductance gradient and synaptic functions. Notably, the device is similar to biological systems in terms of structure and signal carriers, especially for the low operating voltage (200 mV), which matches the biological neural potential (∼110 mV). This work lays the foundation for realizing the function of iontronics neuromorphic computing at ultralow operating voltages and in-memory computing, which can break the limits of information barriers for brain-machine interfaces.


Asunto(s)
Nanotecnología , Sinapsis , Sinapsis/fisiología , Nanotecnología/instrumentación , Electrólitos/química , Nanoestructuras/química , Neuronas/fisiología , Conductividad Eléctrica
12.
Environ Int ; 187: 108673, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38663235

RESUMEN

Metro systems play a crucial role in public transportation worldwide. Given that metro stations are unique built environments with a significant volume of daily commuters, ensuring a satisfactory air quality in these spaces becomes paramount. This study involved measurements of indoor air quality (IAQ), staff satisfaction, particulate matter (PM) chemical composition, and heavy metal health risks at a typical metro station in Tianjin over two seasons. Although the air exchange rate was sufficient to maintain a CO2 concentration less than 1000 ppm, the proportion of staff reporting no sick-building symptoms decreased from 83 % in spring to 25 % in winter. An average mass concentration of PM with an aerodynamic diameter smaller than 2.5 µm (PM2.5) of 68.0 ± 42.2 µg/m3 and an average PM1 mass concentration of 51.8 ± 33.3 µg/m3 were observed on the platform in winter. PM2.5 contained more metal in winter than in spring. PM2.5 in winter contained more metal in winter than in spring. With a lower relative humidity in winter, the coefficient of friction between railway wheels and rails increased, thus increasing particle emission. The carcinogenic risk of Cr on the platform was unacceptable. Moreover, the health risks induced by Ba should be investigated. The findings indicate that PM control at metro stationss, particularly on platforms in winter, should be emphasized.


Asunto(s)
Contaminación del Aire Interior , Material Particulado , Vías Férreas , Síndrome del Edificio Enfermo , China , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/estadística & datos numéricos , Humanos , Material Particulado/análisis , Estaciones del Año , Contaminantes Atmosféricos/análisis , Metales Pesados/análisis , Monitoreo del Ambiente
13.
Clin Med Insights Oncol ; 18: 11795549241245698, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38628841

RESUMEN

Background: Medium- to high-risk classification-gastrointestinal stromal tumors (MH-GIST) have a high recurrence rate and are difficult to treat. This study aims to predict the recurrence of MH-GIST within 3 years after surgery based on clinical data and preoperative Delta-CT Radiomics modeling. Methods: A retrospective analysis was conducted on clinical imaging data of 242 cases confirmed to have MH-GIST after surgery, including 92 cases of recurrence and 150 cases of normal. The training set and test set were established using a 7:3 ratio and time cutoff point. In the training set, multiple prediction models were established based on clinical data of MH-GIST and the changes in radiomics texture of enhanced computed tomography (CT) at different time periods (Delta-CT radiomics). The area under curve (AUC) values of each model were compared using the Delong test, and the clinical net benefit of the model was tested using decision curve analysis (DCA). Then, the model was externally validated in the test set, and a novel nomogram predicting the recurrence of MH-GIST was finally created. Results: Univariate analysis confirmed that tumor volume, tumor location, neutrophil-lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), diabetes, spicy hot pot, CT enhancement mode, and Radscore 1/2 were predictive factors for MH-GIST recurrence (P < .05). The combined model based on these above factors had significantly higher predictive performance (AUC = 0.895, 95% confidence interval [CI] = [0.839-0.937]) than the clinical data model (AUC = 0.735, 95% CI = [0.6 62-0.800]) and radiomics model (AUC = 0.842, 95% CI = [0.779-0.894]). Decision curve analysis also confirmed the higher clinical net benefit of the combined model, and the same results were validated in the test set. The novel nomogram developed based on the combined model helps predict the recurrence of MH-GIST. Conclusions: The nomogram of clinical and Delta-CT radiomics has important clinical value in predicting the recurrence of MH-GIST, providing reliable data reference for its diagnosis, treatment, and clinical decision-making.

14.
Nanoscale Adv ; 6(8): 1974-1991, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38633037

RESUMEN

Sonodynamic therapy (SDT) is an emerging approach for malignant tumor treatment, offering high precision, deep tissue penetration, and minimal side effects. The rapid advancements in nanotechnology, particularly in cancer treatment, have enhanced the efficacy and targeting specificity of SDT. Combining sonodynamic therapy with nanotechnology offers a promising direction for future cancer treatments. In this review, we first systematically discussed the anti-tumor mechanism of SDT and then summarized the common nanotechnology-related sonosensitizers and their recent applications. Subsequently, nanotechnology-related therapies derived using the SDT mechanism were elaborated. Finally, the role of nanomaterials in SDT combined therapy was also introduced.

15.
Front Oncol ; 14: 1394286, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38680855

RESUMEN

Introduction: Nucleic acid-sensing (NAS) pathways could induce innate and adaptive immune responses. However, rare evidence exhibited how the core genes of the NAS pathways affected the immune response and prognosis of small cell lung cancer (SCLC) patients. Methods: We conducted a comprehensive bioinformatic analysis based on the RNA profiles of 114 SCLC patients, including 79 from cBioPortal, 21 from GSE30219, and 14 from our sequencing data. The multiplex immunohistochemistry (mIHC) was used to characterize the role of NAS related genes in the tumor microenvironment (TME) of SCLC. Results: A prognostic model (7NAS risk model) was constructed based on 7 NAS-related genes which was demonstrated as an independent prognostic index. The low-risk group was identified to have a better prognosis and an immune-activated microenvironment in both the public datasets and our dataset. Intriguingly, mIHC data showed that CD45+ immune cells, CD8+ T lymphocytes, and CD68+ macrophages were prevalently enriched in low-risk SCLC patients and positively correlated with IRF1 expression. Additionally, Patients in the low-risk group might have superior responses to chemotherapy and immunotherapy. Conclusion: Conclusively, this study created a new risk model based on genes associated with NAS pathways which could predict the prognosis and response of treatment in patients with SCLC.

16.
Plants (Basel) ; 13(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38674511

RESUMEN

The nitrogen deposition process, as an important phenomenon of global climate change and an important link in the nitrogen cycle, has had serious and far-reaching impacts on grassland ecosystems. This study aimed to investigate the survival adaptation strategies of plants of different functional groups under nitrogen deposition, and the study identified the following outcomes of differences in biomass changes by conducting in situ simulated nitrogen deposition experiments while integrating plant nutrient contents and soil physicochemical properties: (1) nitrogen addition enhanced the aboveground biomass of grassland communities, in which Poaceae were significantly affected by nitrogen addition. Additionally, nitrogen addition significantly influenced plant total nitrogen and total phosphorus; (2) nitrogen addition improved the plant growth environment, alleviated plant nitrogen limitation, and promoted plant phosphorus uptake; and (3) there was variability in the biomass responses of different functional groups to nitrogen addition. The level of nitrogen addition was the primary factor affecting differences in biomass changes, while nitrogen addition frequency was an important factor affecting changes in plant community structure.

17.
Poult Sci ; 103(6): 103745, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38670058

RESUMEN

Fowl adenovirus serotype 11 (FAdV-11) is one of the main causative agents of inclusion body hepatitis (IBH) in broilers. Outbreaks of FAdV-11-related IBH have been increasingly reported in China and many other geographical areas worldwide. However, the critical virulence factors of FAdV-11 remain uncertain due to the lack of technical platforms for efficient manipulation of FAdV-11 genome. Here, we reported the establishment of a FAdV-11 reverse genetic system based on a novel FAdV-11 Chinese isolate FJSW/2021 using the exonuclease combined with RecET (ExoCET), Redαß recombineering and ccdB counter-selection techniques for the first time. A recombinant FAdV-11 was rescued efficiently by using the established reverse genetic platform through swapping the ORF11 gene of the FAdV-11 FJSW/2021 with the ZsGreen fluorescent protein expression cassette. This study provides an effective technical platform for identifying virulence factors of FAdV-11 and developing recombinant FAdV-11-vectored vaccine candidates.

18.
Sensors (Basel) ; 24(7)2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38610313

RESUMEN

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.

19.
J Colloid Interface Sci ; 667: 91-100, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38621335

RESUMEN

The development of efficient and multifunctional sonosensitizers is crucial for enhancing the efficacy of sonodynamic therapy (SDT). Herein, we have successfully constructed a CoOx-loaded amorphous metal-organic framework (MOF) UIO-66 (A-UIO-66-CoOx) sonosensitizer with excellent catalase (CAT)- and glutathione-oxidase (GSH-OXD)-like activities. The A-UIO-66-CoOx exhibits a 2.6-fold increase in singlet oxygen (1O2) generation under ultrasound (US) exposure compared to crystalline UIO-66 sonosensitizer, which is attributed to its superior charge transfer efficiency and consistent oxygen (O2) supply. Additionally, the A-UIO-66-CoOx composite reduces the expression of glutathione peroxidase (GPX4) by depleting glutathione (GSH) through Co3+ and Co2+ valence changes. The high levels of highly cytotoxic 1O2 and deactivation of GPX4 can lead to lethal lipid peroxidation, resulting in concurrent apoptosis and ferroptosis. Both in vitro and vivo tumor models comprehensively confirmed the enhanced SDT antitumor effect using A-UIO-66-CoOx sonosensitizer. Overall, this study emphasizes the possibility of utilizing amorphization engineering to improve the effectiveness of MOFs-based sonosensitizers for combined cancer therapies.


Asunto(s)
Apoptosis , Ferroptosis , Estructuras Metalorgánicas , Terapia por Ultrasonido , Ferroptosis/efectos de los fármacos , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Humanos , Apoptosis/efectos de los fármacos , Animales , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Ratones Endogámicos BALB C , Ensayos de Selección de Medicamentos Antitumorales , Supervivencia Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Tamaño de la Partícula , Cobalto/química , Cobalto/farmacología , Propiedades de Superficie , Oxígeno Singlete/metabolismo , Oxígeno Singlete/química , Línea Celular Tumoral
20.
Environ Pollut ; 349: 123929, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38582190

RESUMEN

Microcystin-LR (MC-LR) is a reproductive toxin produced by cyanobacteria in the aquatic environment and can be ingested by humans through drinking water and the food chain, posing a threat to human reproductive health. However, the toxic mechanisms and prospective interventions for MC-LR-induced ovarian dysfunction at environmental doses are unknown. The mulberry fruit is a traditional natural product of plant origin, with various pharmacological effects, such as antioxidant and anti-inflammatory effects. Here, mice were exposed to MC-LR (10, 100 µg/L) in drinking water for 90 days, during which mice were gavage 600 mg/kg/week of mulberry fruit extract (MFE). It was found that MC-LR can accumulate in mouse ovaries, causing sexual hormone disturbance, inflammatory infiltration, and ovarian pathological damage. Results from RNA-seq were shown that CCL2, a chemokine associated with inflammatory response, was significantly increased in mouse ovary after MC-LR exposure. Further investigation revealed that MC-LR exposure aggravates apoptosis of granulosa cells via the CCL2-CCR10 axis-mediated Jak/Stat pathway. Importantly, MFE can significantly ameliorate these ovarian dysfunction phenotypes by inhibiting the activation of the CCL2-CCR10 axis. This study broadened new insights into the ovarian toxicity of MC-LR and clarified the pharmacological effects of mulberry fruit on ovarian function protection.


Asunto(s)
Toxinas Marinas , Microcistinas , Morus , Animales , Femenino , Microcistinas/toxicidad , Ratones , Morus/química , Ovario/efectos de los fármacos , Quimiocina CCL2/metabolismo , Quimiocina CCL2/genética , Extractos Vegetales/farmacología , Células de la Granulosa/efectos de los fármacos
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