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1.
Langmuir ; 40(24): 12681-12688, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38839051

RESUMO

Photocatalytic conversion of CO2 to hydrocarbon fuel is a potential strategy to solve energy shortage and mitigate the greenhouse effect. Here, direct Z-scheme heterojunction photocatalysts (In2O3/Bi2S3) without an electron mediator are prepared by a simple hydrolysis method. The In2O3/Bi2S3 composite photocatalysts show greatly boosted photoactivity on CO2 conversion to CO compared with the pristine In2O3 and Bi2S3. The highest CO evolution rate of 2.67 µmol·g-1·h-1 is achieved by In2O3/Bi2S3-3, without any sacrificial agent or cocatalyst, which is about 3.87 times that of In2O3 (0.69 µmol·g-1·h-1). The boosted photocatalytic performance of In2O3/Bi2S3 composite catalysts can be ascribed to the establishment of a Z-scheme heterojunction, improving the photoabsorption and facilitating charge separation and transfer. This study provides a reference for designing and fabricating high-efficiency Z-scheme heterojunction photocatalysts for photocatalytic CO2 reduction.

2.
Environ Res ; 251(Pt 1): 118649, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38458589

RESUMO

A novel photocatalyst In2O3 with loading Ag particles is prepared via a facile one-step annealing method in air atmosphere. The Ag/In2O3 exhibits considerable photoactivity for decomposing sulfisoxazole (SOX), tetracycline hydrochloride (TC), and rhodamine B (RhB) under natural sunlight irradiation, which is much higher than that of pristine In2O3 and Ag species. After natural sunlight irradiation for 100 min, 70.6% of SOX, 65.6% of TC, and 81.9% of RhB are degraded over Ag/In2O3, and their corresponding chemical oxygen demand (COD) removal ratio achieve 95.4%, 38.4%, and 93.6%, respectively. A batch of experiments for degrading SOX with adjusting pollutant solution pH and adding coexisting anions over Ag/In2O3 are carried out to estimate its practical application prospect. Particularly, the as-prepared Ag/In2O3 possesses a superior stability, which exhibits no noticeable deactivation in decomposing SOX after eight cycles' reactions. In addition, the Ag/In2O3 coated on a frosted glass plate, also possesses a superior activity and stability for SOX removal, which solve the possible second pollution of residual powdered catalyst in water. Ag particles on In2O3 working as electron accepter improve charge separation and transfer efficiency, as well as the photo-absorption and organic pollutants affinity, leading to the boosted photoactivity of Ag/In2O3. The photocatalytic mechanism for degrading SOX and degradation process over Ag/In2O3 has been systemically investigated and proposed. This work offers an archetype for the rational design of highly efficient photocatalysts by metal loading.


Assuntos
Prata , Luz Solar , Prata/química , Poluentes Químicos da Água/química , Catálise , Rodaminas/química , Fotólise
3.
Biotechnol Appl Biochem ; 71(3): 501-511, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38246885

RESUMO

Arctigenin belongs to a major bioactive component of Fructus arctii and has been found with cardioprotective effects on rats with ischemia‒reperfusion (I/R) injury. The application of arctigenin is limited due to poor water solubility and low bioavailability. Hydrogel drug delivery systems can improve the efficacy and safety of drugs, increase drug utilization, and reduce side effects. We hypothesized that hydrogels containing arctigenin would facilitate the effect of arctigenin and alleviate I/R injury in the rat heart. Presently, adult Sprague-Dawley (SD) rats were subjected to 1 h of I/R injury, then hydrogels comprising arctigenin were implanted into the myocardium of rats. Triphenyl tetrazolium chloride staining, hematoxylin-eosin staining, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining and Western blot were performed for evaluating the infarct size, histopathological, and vital protein alterations of hearts. It was discovered that the hydrogel combined with arctigenin abated apoptosis and reduced infarct size. In addition, the results of echocardiography and Masson staining suggested that the hydrogel with arctigenin improved cardiac function, restrained myocardial fibrosis, and activated AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1). Collectively, the injectable hydrogel delivery system enhances the effect of arctigenin, which may play a protective role in I/R injury by activating AMPK and SIRT1.


Assuntos
Furanos , Hidrogéis , Lignanas , Traumatismo por Reperfusão Miocárdica , Ratos Sprague-Dawley , Animais , Lignanas/farmacologia , Lignanas/química , Lignanas/administração & dosagem , Furanos/química , Furanos/farmacologia , Furanos/administração & dosagem , Ratos , Hidrogéis/química , Hidrogéis/farmacologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Masculino , Sistemas de Liberação de Medicamentos , Miocárdio/patologia , Miocárdio/metabolismo , Apoptose/efeitos dos fármacos , Injeções
4.
Phytother Res ; 38(2): 1044-1058, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38153125

RESUMO

Cardiac dysfunction and arrhythmia are severe complications of sepsis-induced cardiomyopathy and are associated with an increased risk of morbidity and mortality. Currently, the precise mechanism for sepsis-induced myocardial damage remains unclear. Astilbin, a flavonoid, is reported to have anti-inflammatory, antioxidative, and antiapoptotic properties. However, the effects of astilbin on sepsis-induced cardiomyopathy have not been studied so far. This study aims to investigate the effect of astilbin in sepsis-induced myocardial injury and elucidate the underlying mechanism. In vivo and in vitro sepsis models were created using lipopolysaccharide (LPS) as an inducer in H9C2 cardiomyocytes and C57BL/6 mice, respectively. Our results demonstrated that astilbin reduced myocardial injury and improved cardiac function. Moreover, astilbin prolonged the QT and corrected QT intervals, attenuated myocardial electrical remodeling, and promoted gap junction protein (Cx43) and ion channels expression, thereby reducing the susceptibility of ventricular fibrillation. In addition, astilbin alleviated LPS-induced inflammation, oxidative stress, and apoptosis. Astilbin suppressed the toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) pathway in vivo and in vitro models. Astilbin remarkedly upregulated the nuclear factor erythroid 2-related factor 2 (NRF2) and heme oxygenase 1 (HO-1) expression. The in vitro treatment with an NRF2 inhibitor reversed the inhibition of the TLR4/NF-κB pathway and antioxidant properties of astilbin. Astilbin attenuated LPS-induced myocardial injury, cardiac dysfunction, susceptibility to VF, inflammation, oxidative stress, and apoptosis by activating the NRF2/HO-1 pathway and inhibiting TLR4/ NF-κB pathway. These results suggest that astilbin could be an effective and promising therapeutics target for the treatment of sepsis-induced cardiomyopathy.


Assuntos
Cardiomiopatias , Flavonóis , Cardiopatias , Sepse , Camundongos , Animais , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais , Fator 2 Relacionado a NF-E2/metabolismo , Heme Oxigenase-1/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Inflamação , Estresse Oxidativo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Cardiomiopatias/tratamento farmacológico , Sepse/complicações , Sepse/tratamento farmacológico
5.
Sensors (Basel) ; 24(6)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38544209

RESUMO

As an essential reference to bridge dynamic characteristics, the identification of bridge frequencies has far-reaching consequences for the health monitoring and damage evaluation of bridges. This study proposes a uniform scheme to identify bridge frequencies with two different subspace-based methodologies, i.e., an improved Short-Time Stochastic Subspace Identification (ST-SSI) method and an improved Multivariable Output Error State Space (MOESP) method, by simply adjusting the signal inputs. One of the key features of the proposed scheme is the dimensionless description of the vehicle-bridge interaction system and the employment of the dimensionless response of a two-axle vehicle as the state input, which enhances the robustness of the vehicle properties and speed. Additionally, it establishes the equation of the vehicle biaxial response difference considering the time shift between the front and the rear wheels, theoretically eliminating the road roughness information in the state equation and output signal effectively. The numerical examples discuss the effects of vehicle speeds, road roughness conditions, and ongoing traffic on the bridge identification. According to the dimensionless speed parameter Sv1 of the vehicle, the ST-SSI (Sv1 < 0.1) or MOESP (Sv1 ≥ 0.1) algorithm is applied to extract the frequencies of a simply supported bridge from the dimensionless response of a two-axle vehicle on a single passage. In addition, the proposed methodology is applied to two types of long-span complex bridges. The results show that the proposed approaches exhibit good performance in identifying multi-order frequencies of the bridges, even considering high vehicle speeds, high levels of road surface roughness, and random traffic flows.

6.
J Environ Manage ; 363: 121393, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850920

RESUMO

Defect engineering is regarded as an effective strategy to boost the photo-activity of photocatalysts for organic contaminants removal. In this work, abundant surface oxygen vacancies (Ov) are created on AgIO3 microsheets (AgIO3-OV) by a facile and controllable hydrogen chemical reduction approach. The introduction of surface Ov on AgIO3 broadens the photo-absorption region from ultraviolet to visible light, accelerates the photoinduced charges separation and migration, and also activates the formation of superoxide radicals (•O2-). The AgIO3-OV possesses an outstanding degradation rate constant of 0.035 min-1, for photocatalytic degrading methyl orange (MO) under illumination of natural sunlight with a light intensity is 50 mW/cm2, which is 7 and 3.5 times that of the pristine AgIO3 and C-AgIO3 (AgIO3 is calcined in air without generating Ov). In addition, the AgIO3-OV also exhibit considerable photoactivity for degrading other diverse organic contaminants, including azo dye (rhodamine B (RhB)), antibiotics (sulflsoxazole (SOX), norfloxacin (NOR), chlortetracycline hydrochloride (CTC), tetracycline hydrochloride (TC) and ofloxacin (OFX)), and even the mixture of organic contaminants (MO-RhB and CTC-OFX). After natural sunlight illumination for 50 min, 41.4% of total organic carbon (TOC) for MO-RhB mixed solution can be decreased over AgIO3-OV. In a broad range of solution pH from 3 to 11 or diverse water bodies of MO solution, AgIO3-OV exhibits attractive activity for decomposing MO. The MO photo-degradation process and mechanism over AgIO3-OV under natural sunlight irradiation has been systemically investigated and proposed. The toxicities of MO and its degradation intermediates over AgIO3-OV are compared using Toxicity Estimation Software (T.E.S.T.). Moreover, the non-toxicity of both AgIO3-OV catalyst and treated antibiotic solution (CTC-OFX mixture) are confirmed by E. coli DH5a cultivation test, supporting the feasibility of AgIO3-OV catalyst to treat organic contaminants in real water under natural sunlight illumination.


Assuntos
Fotólise , Luz Solar , Oxigênio/química , Poluentes Químicos da Água/química , Compostos Azo/química , Catálise , Rodaminas/química
7.
Cancer Cell Int ; 23(1): 242, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37840147

RESUMO

Epigenetic modifications have long been recognized as an essential level in transcriptional regulation linking behavior and environmental conditions or stimuli with biological processes and disease development. Among them, methylation is the most abundant of these reversible epigenetic marks, predominantly occurring on DNA, RNA, and histones. Methylation modification is intimately involved in regulating gene transcription and cell differentiation, while aberrant methylation status has been linked with cancer development in several malignancies. Early detection and precise restoration of dysregulated methylation form the basis for several epigenetics-based therapeutic strategies. In this review, we summarize the current basic understanding of the regulation and mechanisms responsible for methylation modification and cover several cutting-edge research techniques for detecting methylation across the genome and transcriptome. We then explore recent advances in clinical diagnostic applications of methylation markers of various cancers and address the current state and future prospects of methylation modifications in therapies for different diseases, especially comparing pharmacological methylase/demethylase inhibitors with the CRISPRoff/on methylation editing systems. This review thus provides a resource for understanding the emerging role of epigenetic methylation in cancer, the use of methylation-based biomarkers in cancer detection, and novel methylation-targeted drugs.

8.
Int J Mol Sci ; 24(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37047268

RESUMO

Femoral head necrosis (FHN) is a common leg disease in broilers, resulting in economic losses in the poultry industry. The occurrence of FHN is closely related to the decrease in the number of bone marrow mesenchymal stem cells (BMSCs) and the change in differentiation direction. This study aimed to investigate the function of differentiation of BMSCs in the development of FHN. We isolated and cultured BMSCs from spontaneous FHN-affected broilers and normal broilers, assessed the ability of BMSCs into three lineages by multiple staining methods, and found that BMSCs isolated from FHN-affected broilers demonstrated enhanced lipogenic differentiation, activated Notch-RBPJ signaling pathway, and diminished osteogenic and chondrogenic differentiation. The treatment of BMSCs with methylprednisolone (MP) revealed a significant decrease in the expressions of Runx2, BMP2, Col2a1 and Aggrecan, while the expressions of p-Notch1/Notch1, Notch2 and RBPJ were increased significantly. Jagged-1 (JAG-1, Notch activator)/DAPT (γ-secretase inhibitor) could promote/inhibit the osteogenic or chondrogenic ability of MP-treated BMSCs, respectively, whereas the differentiation ability of BMSCs was restored after transfection with si-RBPJ. The above results suggest that the Notch-RBPJ pathway plays important role in FHN progression by modulating the osteogenic and chondrogenic differentiation of BMSCs.


Assuntos
Necrose da Cabeça do Fêmur , Células-Tronco Mesenquimais , Animais , Células da Medula Óssea , Diferenciação Celular , Células Cultivadas , Galinhas , Necrose da Cabeça do Fêmur/terapia , Necrose da Cabeça do Fêmur/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Receptores Notch/metabolismo
9.
J Environ Manage ; 323: 116236, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36150351

RESUMO

The photocatalytic CO2 reduction reaction is a multi-electron process, which is greatly affected by the surface electron density. In this work, we synthesize Ag clusters supported on In2O3 plasmonic photocatalysts. The Ag-In2O3 compounds show remarkedly enhanced photocatalytic activity for CO2 conversion to CO compared to pristine In2O3. In the absence of any co-catalyst or sacrificial agent, the CO evolution rate of optimal Ag-In2O3-10 is 1.56 µmol/g/h, achieving 5.38-folds higher than that of In2O3 (0.29 µmol/g/h). Experimental verification and DFT calculation demonstrate that electrons transfer from Ag clusters to In2O3 on Ag-In2O3 compounds. In Ag-In2O3 compounds, Ag clusters serving as electron donators owing to the SPR behaviour are not helpful to decline photo-induced charge recomnation rate, but can provide more electron for photocatalytic reaction. Overall, the Ag clusters promote visible-light absorption and accelerate photocatalytic reaction kinetic for In2O3, resulting in the photocatalytic activity enhancement of Ag-In2O3 compounds. This work puts insight into the function of plasmonic metal on enhancing photocatalysis performance, and provides a feasible strategy to design and fabricate efficient plasmonic photocatalysts.

11.
Sensors (Basel) ; 19(17)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466268

RESUMO

Human falls are the premier cause of fatal and nonfatal injuries among older adults. The health outcome of a fall event is largely dependent on rapid response and rescue of the fallen elder. Being able to provide an accurate and fast fall detection will dramatically improve the health outcomes of the older population and reduce the associated healthcare cost after a fall. To achieve the goal, a multi-features semi-supervised support vector machines (MFSS-SVM) algorithm utilizing measurements from structural floor vibration obtained through accelerometers is proposed in this study to detect falling events with limited labeled samples. In this MFSS-SVM algorithm, the peak value, energy, and correlation coefficient of the accelerometer signal are used as classification features. The performance of the proposed algorithm was validated with laboratory experiments among activities including falling, walking, free jumping, rhythmic jumping, bag dropping, and ball dropping. To further illustrate the performance of the algorithm, a benchmark database was adopted and expanded to test its ability to accurately identify falling, compared with the algorithm used in the benchmark study. Results show that by using the proposed algorithm, the falling events can be identified with high accuracy and confidence, even with small training datasets and test nodes.


Assuntos
Acidentes por Quedas/prevenção & controle , Máquina de Vetores de Suporte , Vibração , Caminhada/fisiologia , Algoritmos , Humanos
12.
J Opt Soc Am A Opt Image Sci Vis ; 33(7): 1267-76, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27409682

RESUMO

Registration of retinal images taken at different times, from different perspectives, or with different modalities is a critical prerequisite for the diagnoses and treatments of various eye diseases. This problem can be formulated as registration of two sets of sparse feature points extracted from the given images, and it is typically solved by first creating a set of putative correspondences and then removing the false matches as well as estimating the spatial transformation between the image pairs or solved by estimating the correspondence and transformation jointly involving an iteration process. However, the former strategy suffers from missing true correspondences, and the latter strategy does not make full use of local appearance information, which may be problematic for low-quality retinal images due to a lack of reliable features. In this paper, we propose a feature-guided Gaussian mixture model (GMM) to address these issues. We formulate point registration as the estimation of a feature-guided mixture of densities: A GMM is fitted to one point set, such that both the centers and local features of the Gaussian densities are constrained to coincide with the other point set. The problem is solved under a unified maximum-likelihood framework together with an iterative expectation-maximization algorithm initialized by the confident feature correspondences, where the image transformation is modeled by an affine function. Extensive experiments on various retinal images show the robustness of our approach, which consistently outperforms other state-of-the-art methods, especially when the data is badly degraded.


Assuntos
Processamento de Imagem Assistida por Computador , Modelos Estatísticos , Imagem Molecular , Retina/citologia , Algoritmos , Humanos , Distribuição Normal
13.
J Opt Soc Am A Opt Image Sci Vis ; 33(7): 1313-22, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27409688

RESUMO

In this paper, we propose a novel formulation for building pixelwise alignments between remote sensing images under nonrigid transformation based on matching both sparsely and densely sampled features. Our formulation contains two coupling variables: the nonrigid geometric transformation and the discrete dense flow field. To match sparse features, we fit a geometric transformation specified in a reproducing kernel Hilbert space and impose a locally linear constraint to regularize the transformation. To match dense features, we compute a dense flow field by using a formulation analogous to scale invariant feature transform (SIFT) flow which allows nonrigid matching across different scene appearances. An additional term is introduced to ensure the coherence between the two variables, and we alternatively solve for one variable under the assumption that the other is known. Extensive experiments on both synthetic and real remote sensing images demonstrate that our approach greatly outperforms state-of-the-art methods, particularly when the data contain severe degradations.

14.
Med Sci Monit ; 22: 3056-61, 2016 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-27571235

RESUMO

BACKGROUND This study aimed to investigate the role of miR-184 in the proliferation and apoptosis of keratinocyte (HaCaT cells). MATERIAL AND METHODS HaCaT cells were cultured in a growth medium. The miR-184 was transfected with siRNA, then cell viability and apoptosis were assayed by MTT and flow cytometry, respectively. The colony-forming efficacy of HaCaT cells were detected as well. mRNA expressions of basic fibroblast growth factor (bFGF) and transforming growth factor (TGF)-ß1 were measured with RT-PCR. The expressions of apoptosis-related proteins caspase-3 and Bcl-x in HaCaT cells were determined by Western blot. RESULTS After miR-184 was transfected with siRNA, cell viability and colony forming ability decreased significantly, and apoptosis was significantly increased. The expressions of growth factors TGF-ß1 and bFGF mRNAs, as well as apoptosis-related proteins Bcl-x, in HaCaT cells declined significantly after miR-184 was transfected with siRNA. In addition, the expression of pro-apoptotic protein caspase-3 increased significantly. CONCLUSIONS Our results suggest distinct roles of miR-184 during the growth, proliferation, and apoptosis of keratinocytes.


Assuntos
Queratinócitos/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Transfecção , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
15.
Sensors (Basel) ; 16(11)2016 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-27827975

RESUMO

Heterogeneous wireless sensor networks (HWSNs) are widely adopted in structural health monitoring systems due to their potential for implementing sophisticated algorithms by integrating a diverse set of devices and improving a network's sensing performance. However, deploying such a HWSN is still in a challenge due to the heterogeneous nature of the data and the energy constraints of the network. To respond to these challenges, an optimal deployment framework in terms of both modal information quality and energy consumption is proposed in this study. This framework generates a multi-objective function aimed at maximizing the quality of the modal information identified from heterogeneous data while minimizing the consumption of energy within the network at the same time. Particle swarm optimization algorithm is then implemented to seek solutions to the function effectively. After laying out the proposed sensor-optimization framework, a methodology is present to determine the clustering of the sensors to further conserve energy. Finally, a numerical verification is performed on a four-span pre-stressed reinforced concrete box-girder bridge. Results show that a set of strategically positioned heterogeneous sensors can maintain a balanced trade-off between the modal information accuracy and energy consumption. It is also observed that an appropriate cluster-tree network topology can further achieve energy saving in HWSNs.


Assuntos
Tecnologia sem Fio/instrumentação , Algoritmos , Redes de Comunicação de Computadores , Simulação por Computador
16.
Inorg Chem ; 54(4): 1876-82, 2015 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-25622046

RESUMO

Cr(3+)-activated mullite-type Bi2Ga(4-x)Al(x)O9 (x = 0, 1, 2, 3, and 4) solid solutions were prepared by the solid state reaction, and their spectroscopic properties were investigated in conjunction with the structural evolution. Under excitation at 610 nm, Bi2[Ga(4-y)Al(y)]3.97O9:0.03Cr(3+) (y = 0, 1, 2, 3, and 4) phosphors exhibited broad-band near-infrared (NIR) emission peaking at ∼710 nm in the range 650-850 nm, and the optimum Cr(3+) concentrations and concentration quenching mechanism were determined. Except for the interesting NIR emission, the body color changed from white (at x = 0) to green (at x = 0.08) for Bi2Ga(4-x)O9:xCr(3+), and from light yellow (at x = 0) to deep brown (at x = 0.08) for Bi2Al(4-x)O9:xCr(3+), respectively. Moreover, as a result of variable Al/Ga ratio, the observed body color for Bi2[Ga(4-y)Al(y)]3.97O9:0.03Cr(3+) (y = 0, 1, 2, 3, and 4) varied from deep brown to green. The relationship between the observed colors and their diffuse reflectance spectra were also studied for the understanding of the different absorption bands. The results indicated that Cr(3+)-doped Bi2Ga(4-x)Al(x)O9 solid solutions appeared as the bifunctional materials with NIR phosphors and color-tunable pigments.

17.
ScientificWorldJournal ; 2014: 193284, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25013847

RESUMO

This paper investigates potential applications of the rough sets (RS) theory and artificial neural network (ANN) method on structural damage detection. An information entropy based discretization algorithm in RS is applied for dimension reduction of the original damage database obtained from finite element analysis (FEA). The proposed approach is tested with a 14-bay steel truss model for structural damage detection. The experimental results show that the damage features can be extracted efficiently from the combined utilization of RS and ANN methods even the volume of measurement data is enormous and with uncertainties.


Assuntos
Algoritmos , Redes Neurais de Computação , Aço/normas , Acelerometria/instrumentação , Acelerometria/métodos , Testes de Dureza/métodos
18.
Onco Targets Ther ; 17: 499-506, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911906

RESUMO

RET rearrangements are recognized drivers in lung cancer, representing a small subset (1-2%) of non-small cell lung cancer (NSCLC). Additionally, RET fusions also serve as a rare acquired resistance mechanism in EGFR-mutant NSCLC. Only a few NSCLC cases have been reported with co-occurrence of EGFR mutations and RET fusions as an acquired resistance mechanism induced by EGFR-tyrosine kinase inhibitors (TKIs). A 68-year-old man diagnosed with lung adenocarcinoma harboring EGFR L858R mutation initially responded well to dacomitinib, a second-generation EGFR-tyrosine kinase inhibitor (TKI). Afterward, he developed acquired resistance accompanied by a RET rearrangement. Next-generation sequencing (NGS) analysis revealed that the tumor possessed both the new CCDC6-RET fusion and the EGFR L858R mutation. Subsequently, he was treated with a combination of cisplatin, pemetrexed, and bevacizumab resulting in a partial response. Nevertheless, his condition deteriorated as the disease progressed, manifesting as hydrocephalus, accompanied by altered consciousness and lower limb weakness. The subsequent combined treatment with dacomitinib and selpercatinib resulted in a significant improvement in neurological symptoms. Here, we first identified acquired CCDC6-RET fusion with a coexisting EGFR L858R mutation following dacomitinib treatment. Our findings highlight the importance of NGS for identifying RET fusions and suggest the potential combination of dacomitinib and selpercatinib to overcome this resistance. For NSCLC patients with RET rearrangements and no access to RET inhibitors, pemetrexed-based chemotherapy provides a feasible alternative.

19.
Environ Pollut ; 344: 123325, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38190871

RESUMO

In this work, a series of hydrogenated Fe-doped AgIO3 (FAI-x) catalysts are synthesized for photodegrading diverse azo dyes and antibiotics. Under the irradiation of natural sunlight with a light intensity of ∼60 mW/cm2, the optimum FAI-10 exhibits a considerable rate constant for decomposing methyl orange (MO) of 0.067 min-1, about 7.4 times higher than that of AgIO3 (0.009 min-1), and 24.6% and 83.8% of MO can be decomposed over AgIO3 and FAI-10 after irradiation for 40 min. In the amplification photodegradation experiments with using 0.5 g catalyst and 400 mL MO dye solution (10 mg/L), FAI-10 possesses greatly higher photoreactivity to common semiconductors (ZnO, TiO2, In2O3 and Bi2MoO6), and the photodegradation rates over FAI-10 are 92%. Particularly, the FAI-10 shows superior stability, the activity of which remains unaltered after 8 continuous cycles. Foreign ions and water bodies have slight effect on the activity of FAI-10, but the MO degradation rates are decreased by adjusting pH values, especially when pH = 11 because of the strong electrostatic repulsion between MO and FAI-10. FAI-10 can also effectively decompose another azo dye (rhodamine B (RhB)) and diverse antibiotics (sulflsoxazole (SOX), chlortetracycline hydrochloride (CTC), tetracycline hydrochloride (TC) and ofloxacin (OFX)). The activity enhancement mechanism of FAI-10 has been systemically investigated and is ascribed to the promoted photo-absorption, charge separation and transfer efficiency, and affinity of organic pollutants, owing to the synergistic effect of Fe doping and oxygen vacancy (Ov). The photocatalytic mechanisms and process for decomposing MO are verified and proposed based on radical trapping experiments and liquid chromatography-mass spectrometry (LC-MS). This work opens an avenue for the fabrication of effective photocatalysts toward water purification.


Assuntos
Compostos Azo , Poluentes Ambientais , Oxigênio/química , Luz Solar , Luz , Antibacterianos , Catálise
20.
Theriogenology ; 230: 130-141, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39298912

RESUMO

Testosterone is secreted by Leydig cells (LCs), which play an important physiological role in preserving male secondary sex characteristics, protecting male reproductive function, and establishing the blood-testis barrier. Studies have shown that autophagy is particularly active in LCs; however, its involvement in testosterone synthesis in porcine LCs has not been fully explored. Therefore, this experiment aimed to investigate the influence of autophagy on testosterone secretion in porcine LCs and its potential regulatory mechanism. Our results demonstrated that both testicular autophagy and serum testosterone levels increased in piglets during postnatal development from 4 to 18 weeks. In addition, autophagy was found to degrade the Na+/H+ exchange regulatory factor 2 (NHERF2), leading to the up-regulation of scavenger receptor class B type 1 (SRB1). This process resulted in increased cholesterol intake and enhanced testosterone production. The observable level of sirtuin 1 (SIRT1) was directly proportional to the level of autophagy. In vitro investigations have shown that SIRT1 can affect the level of autophagy, cholesterol uptake as well as testosterone release. In conclusion, testosterone synthesis during pig development is regulated by SIRT1. SIRT1 mediates the degradation of NHERF2 through autophagy, thereby weakening its negative regulatory effect on the high-density lipoprotein receptor SRB1 in Leydig cells. This process increases cholesterol uptake and enhances testosterone synthesis.

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