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1.
Phytochemistry ; 228: 114229, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39127395

RESUMO

Scoparodane C (1), a diterpenoid with a rare 3,4-seco-3-nor-2,11-epoxy-ent-clerodane scaffold, was obtained from the aerial parts of Isodon scoparius, along with isocopariusines A-E (2-6), five ent-clerodanoids featuring a 5/6-fused ring system, and isocopariusines F-H (7-9), three common ent-clerodanoids. The structures of these previously undescribed compounds were established by a combination of spectroscopic analysis, X-ray diffraction, chemical derivatization, and quantum chemical calculation. Remarkably, isocopariusine B (3) showed strong resistance reversal activity against fluconazole-resistant Candida albicans.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39129165

RESUMO

INTRODUCTION: One of the many reasons for cancer treatment failure and recurrence is acquired Multidrug Resistance (MDR). Overcoming cancer drug resistance has been the focus of researchers' studies. Cellular prion protein (PrPC) is a glycophosphatidylinositol-anchored cell-surface glycoprotein that has been implicated in tumor behavior, including proliferation, apoptosis, invasion, metastasis, and chemoresistance. >Method: Lupiwighteone (Lup), a natural isoflavone found in the root of Glycyrrhiza glabra, has anticancer activity against prostate cancer cells, neuroblastoma cells, and human breast cancer cells. However, its pharmacological effects and mechanisms in drug-resistant cancer cells have not been reported. In this study, we used an adriamycin- resistant leukemia K562 cell model, and for the first time, we investigated the reversal effect of Lup on its MDR and the potential mechanism. RESULT: The results indicated that Lup could induce apoptosis through the mitochondrial pathway while upregulating the expression of related apoptotic proteins, such as Bax, Cyto C, Caspase-3, and PARP1. Autophagy is commonly recognized as a protective mechanism that mediates MDR during treatment. We found that Lup induced cellular autophagy while upregulating the expression of related autophagy proteins such as Beclin 1 and LC3 II. CONCLUSION: In addition, when Lup was combined with adriamycin, Lup decreased the IC50 of K562/ADR cells; moreover, Lup can downregulate the expression of drug-resistant proteins, suggesting that Lup can reverse drug resistance. Further studies have shown that Lup can downregulate the expression of PrPC-PI3K-Akt axis proteins and PrPC-Oct4 axis proteins. This study demonstrated that Lup has the potential to inhibit the proliferation of K562/ADR cells by targeting PrPC, and further study of the signaling pathway associated with PrPC may provide the experimental basis for the treatment of drug-resistant leukemia.

3.
Alzheimers Dement ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136296

RESUMO

BACKGROUND: Education influences brain health and dementia. However, its impact across regions, specifically Latin America (LA) and the United States (US), is unknown. METHODS: A total of 1412 participants comprising controls, patients with Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD) from LA and the US were included. We studied the association of education with brain volume and functional connectivity while controlling for imaging quality and variability, age, sex, total intracranial volume (TIV), and recording type. RESULTS: Education influenced brain measures, explaining 24%-98% of the geographical differences. The educational disparities between LA and the US were associated with gray matter volume and connectivity variations, especially in LA and AD patients. Education emerged as a critical factor in classifying aging and dementia across regions. DISCUSSION: The results underscore the impact of education on brain structure and function in LA, highlighting the importance of incorporating educational factors into diagnosing, care, and prevention, and emphasizing the need for global diversity in research. HIGHLIGHTS: Lower education was linked to reduced brain volume and connectivity in healthy controls (HCs), Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD). Latin American cohorts have lower educational levels compared to the those in the United States. Educational disparities majorly drive brain health differences between regions. Educational differences were significant in both conditions, but more in AD than FTLD. Education stands as a critical factor in classifying aging and dementia across regions.

4.
J Dtsch Dermatol Ges ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39121358

RESUMO

OBJECTIVE: To construct a predictive model for Psoriatic Arthritis (PsA) based on clinical and ultrasonic characteristics in patients with plaque psoriasis (PsP). PATIENTS AND METHODS: Demographic, clinical, and ultrasound data were collected from patients with PsP and PsA between May 2019 and December 2022. RESULTS: A total of 212 patients with PsP and 123 with PsA in the training cohort, whereas the validation cohort comprised 91 patients with PsP and 49 with PsA. The multivariate logistic regression identified nail psoriasis (odds ratio [OR] 1.88, 95% CI: 1.07-3.29), synovitis (OR 18.23, 95% CI: 4.04-82.33), enthesitis (OR 3.71, 95% CI: 1.05-13.14), and bone erosion (OR 11.39, 95% CI: 3.05-42.63) as effective predictors for PsA. The area under the curve was 0.750 (95% CI, 0.691-0.806) and 0.804 (95% CI, 0.723-0.886) for the training and validation cohorts, respectively. The Hosmer-Lemeshow goodness-of-fit test showed good consistency for both the training cohort (p  =  0.970) and the validation cohort (p  =  0.967). Calibration curves also indicated good calibration for both cohorts. The DCA revealed that the predictive model had good clinical utility. CONCLUSIONS: We have developed a quantitative, intuitive, and convenient predictive model based on nail psoriasis, synovitis, enthesitis, and bone erosion to assess the risk of PsA in patients with plaque psoriasis.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39117505

RESUMO

INTRODUCTION AND FRAMEWORK: Sleep capital contributes to individual and societal wellbeing, productivity, and economic outcomes and involves a novel aspect of brain capital. It encompasses the quality and quantity of sleep as integral components that influence cognitive abilities, mental and brain health, and physical health, affecting workplace productivity, learning, decision-making, and overall economic performance. Here, we bring a framework to understand the complex relationship between sleep quality, health, wellbeing, and economic productivity. Then we outline the multilevel impact of sleep on cognitive abilities, mental/brain health, and economic indicators, providing evidence for the substantial returns on investment in sleep health initiatives. Moreover, sleep capital is a key factor when considering brain health across the lifespan, especially for the aging population. DISCUSSION: We propose specific elements and main variables to develop specific indexes of sleep capital to address its impacts on health, wellbeing and productivity. CONCLUSION: Finally, we suggest policy recommendations, workplace interventions, and individual strategies to promote sleep health and brain capital. Investing in sleep capital is essential for fostering a healthier, happier, fairer and more productive society.

6.
ACS Omega ; 9(30): 32579-32592, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39100352

RESUMO

In the domain of geotechnical engineering, a profound understanding of the long-term mechanical deformation characteristics of rocks is indispensable for the design and construction of structures, dams, tunnels, and various engineering projects. The deformation behavior of rocks under long-term loads directly impacts the stability and safety of engineering structures. This study employs micromechanical methods to investigate the subcritical extension of microcracks under stress corrosion. By examining the accumulated damage resulting from this phenomenon, the research explores the patterns of aging damage development and establishes a constitutive model for aging that incorporates cumulative damage over the stress history. The accuracy of the proposed model is evaluated through a comprehensive comparison of numerical results with experimental data. The experimental data set encompasses traditional triaxial compression tests, single-stage creep, multistage creep, and single-stage relaxation tests conducted under varying confining pressures. The predicted results exhibit strong consistency with the entire data set. Furthermore, this paper employs crack damage stress as an indicator characterizing the long-term strength of rock. Through frictional damage coupling analysis and derivation, an analytical expression for the long-term strength of rock materials containing microcracks is provided, serving as a theoretical basis for investigating the long-term mechanical performance of brittle rock materials and ensuring the long-term stability of large-scale rock engineering projects.

8.
Environ Health (Wash) ; 2(7): 486-498, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39049896

RESUMO

Linalool, a high-reactivity volatile chemical product (VCP) commonly found in cleaning products and disinfectants, is increasingly recognized as an emerging contaminant, especially in indoor air. Understanding the gas-phase oxidation mechanism of linalool is crucial for assessing its impact on atmospheric chemistry and human health. Using quantum chemical calculations and computational toxicology simulations, we investigated the atmospheric transformation and toxicity evolution of linalool under low and high NO/HO2· levels, representing indoor and outdoor environments. Our findings reveal that linalool can undergo the novel mechanisms involving concerted peroxy (RO2·) and alkoxy radical (RO·) modulated autoxidation, particularly emphasizing the importance of cyclization reactions indoors. This expands the widely known RO2·-dominated H-shift-driven autoxidation and proposes a generalized autoxidation mechanism that leads to the formation of low-volatility secondary organic aerosol (SOA) precursors. Toxicological analysis shows that over half of transformation products (TPs) exhibited higher carcinogenicity and respiratory toxicity compared to linalool. We also propose time-dependent toxic effects of TPs to assess their long-term toxicity. Our results indicate that the strong indoor emission coupled with slow consumption rates lead to significant health risks under an indoor environment. The results highlight complex indoor air chemistry and health concerns regarding persistent toxic products during indoor cleaning, which involves the use of linalool or other VCPs.

9.
Res Sq ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38978575

RESUMO

Brain clocks, which quantify discrepancies between brain age and chronological age, hold promise for understanding brain health and disease. However, the impact of multimodal diversity (geographical, socioeconomic, sociodemographic, sex, neurodegeneration) on the brain age gap (BAG) is unknown. Here, we analyzed datasets from 5,306 participants across 15 countries (7 Latin American countries -LAC, 8 non-LAC). Based on higher-order interactions in brain signals, we developed a BAG deep learning architecture for functional magnetic resonance imaging (fMRI=2,953) and electroencephalography (EEG=2,353). The datasets comprised healthy controls, and individuals with mild cognitive impairment, Alzheimer's disease, and behavioral variant frontotemporal dementia. LAC models evidenced older brain ages (fMRI: MDE=5.60, RMSE=11.91; EEG: MDE=5.34, RMSE=9.82) compared to non-LAC, associated with frontoposterior networks. Structural socioeconomic inequality and other disparity-related factors (pollution, health disparities) were influential predictors of increased brain age gaps, especially in LAC (R2=0.37, F2=0.59, RMSE=6.9). A gradient of increasing BAG from controls to mild cognitive impairment to Alzheimer's disease was found. In LAC, we observed larger BAGs in females in control and Alzheimer's disease groups compared to respective males. Results were not explained by variations in signal quality, demographics, or acquisition methods. Findings provide a quantitative framework capturing the multimodal diversity of accelerated brain aging.

10.
Org Lett ; 26(29): 6203-6208, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39004824

RESUMO

Isoxerophilusins A (1) and B (2), two unprecedented diterpene heterodimers biogenetically from ent-atisanes and abietanes, were isolated from the rhizomes of Isodon xerophilus. Their structures were determined by extensive spectroscopic analysis and single-crystal X-ray diffraction. Selective esterification of 1 generated 11 new derivatives. All derivatives showed excellent α-glucosidase inhibitory activity in comparison to acarbose. Compounds 12 and 13 demonstrated significant inhibition against α-glucosidase with IC50 values of 4.92 and 3.83 µM, respectively.


Assuntos
Diterpenos , Inibidores de Glicosídeo Hidrolases , Isodon , alfa-Glucosidases , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Diterpenos/química , Diterpenos/farmacologia , Diterpenos/isolamento & purificação , alfa-Glucosidases/metabolismo , Estrutura Molecular , Isodon/química , Dimerização , Cristalografia por Raios X , Relação Estrutura-Atividade , Rizoma/química
11.
Plants (Basel) ; 13(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38891341

RESUMO

Deep sowing is an efficient strategy for maize to ensure the seedling emergence rate under adverse conditions such as drought or low temperatures. However, the genetic basis of deep-sowing tolerance-related traits in maize remains largely unknown. In this study, we performed a genome-wide association study on traits related to deep-sowing tolerance, including mesocotyl length (ML), coleoptile length (CL), plumule length (PL), shoot length (SL), and primary root length (PRL), using 255 maize inbred lines grown in three different environments. We identified 23, 6, 4, and 4 quantitative trait loci (QTLs) associated with ML, CL, PL, and SL, respectively. By analyzing candidate genes within these QTLs, we found a γ-tubulin-containing complex protein, ZmGCP2, which was significantly associated with ML, PL, and SL. Loss of function of ZmGCP2 resulted in decreased PL, possibly by affecting the cell elongation, thus affecting SL. Additionally, we identified superior haplotypes and allelic variations of ZmGCP2 with a longer PL and SL, which may be useful for breeding varieties with deep-sowing tolerance to improve maize cultivation.

12.
Res Sq ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38883786

RESUMO

This work aims to evaluate associations between self-reported sleep health and frailty in Botswana, a sub-Saharan Africa setting. Fifty persons living with HIV (PLWH) on suppressive antiretroviral therapy (ART) and fifty HIV seronegative control participants are enrolled in Botswana. Sleep quality is scored subjectively as "good" or "poor" based on self-report. A frailty index (FI) is constructed based on thirty-three health deficits related to body mass index, waist circumference, physical activity, emotional status, and fatigue, and scored ranging between 0 (no deficit present) and 1 (all deficits present). Sleep quality between PLWH and controls is compared using logistic regression; linear regression is performed to compare the FI between them. Linear regressions are performed to examine the association between the FI and sleep quality stratified by HIV serostatus. Age, sex, and comorbidities are adjusted; when relevant, CD4 cell and ART duration are controlled. PLWH display 2.88 (95% CI: 1.22-6.79, p = 0.02) higher odds of having poor sleep than controls. Having poor sleep is associated with increased FI in PLWH but not in controls. Specifically, compared with PLWH who have good sleep, PLWH who report poor sleep have a > 1 standard deviation (p < 0.0001) increase in their FI score.

13.
J Agric Food Chem ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38841893

RESUMO

Alzheimer's disease (AD), one of the neurodegenerative disorders, is highly correlated with the abnormal hyperphosphorylation of Tau and aggregation of ß-amyloid (Aß). Oxidative stress, neuroinflammation, and abnormal autophagy are key drivers of AD and how they contribute to neuropathology remains largely unknown. The flavonoid compound pongamol is reported to possess a variety of pharmacological activities, such as antioxidant, antibacterial, and anti-inflammatory. This study investigated the neuroprotective effect and its mechanisms of pongamol in lipopolysaccharide (LPS)-induced BV2 cells, d-galactose/sodium nitrite/aluminum chloride (d-gal/NaNO2/AlCl3)-induced AD mice, and Caenorhabditis elegans models. Our research revealed that pongamol reduced the release of inflammatory factors IL-1ß, TNF-α, COX-2, and iNOS in LPS-induced BV2 cells. Pongamol also protected neurons and significantly restored memory function, inhibited Tau phosphorylation, downregulated Aß aggregation, and increased oxidoreductase activity in the hippocampus of AD mice. In addition, pongamol reversed the nuclear transfer of NF-κB and increased the levels of Beclin 1 and LC3 II/LC3 I. Most importantly, the anti-inflammatory and promoter autophagy effects of pongamol may be related to the regulation of the Akt/mTOR signaling pathway. In summary, these results showed that pongamol has a potential neuroprotective effect, which greatly enriched the research on the pharmacological activity of pongamol for improving AD.

14.
Adv Mater ; : e2405035, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38936842

RESUMO

Integration of solar cells and electrochromic windows offers crucial contributions to green buildings. Solar-charging zinc anode-based electrochromic devices (ZECDs) present opportunities for addressing the solar intermittency issue. However, the limited energy storage capacity of ZECDs results in wasted harnessing of solar energy as well as overcharging. Herein, spectral-selective dual-band ZECDs that continuously transport solar energy to indoor appliances by remotely controlling the repeated bleached-tinted cycles during the daytime, are reported. Hexagonal phase cesium-doped tungsten bronze (h-Cs0.32WO3, CWO) nanocrystals are adopted for dual-band ZECDs due to their independent control ability of near-infrared (NIR) and visible (VIS) light transmittance (∆T = 73.0%, 700 nm; ∆T = 83.7%, 1200 nm) and excellent cycling stability (0.8% optical contrast decay at 1200 nm after 10 000 cycles). The prototype device (i.e., CWO//Zn//CWO) delivers extraordinary thermal insulation capability, displaying a 10 °C difference between "bright" and "dark" modes. Furthermore, an Internet of Things (IoT) controller to control the NIR and VIS lights of the CWO//Zn//CWO window wirelessly with a smartphone, empowering the continuous discharging of the solar-charged window during the daytime remotely, is developed. Such windows represent an intriguing potential technology whose future impact on green buildings may be substantial.

15.
Food Chem ; 455: 139679, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38823125

RESUMO

This study involved the preparation of nanoparticles by combining oxidized starch (OS) with xanthan gum (XG), and emulsions were prepared from this nanoparticle. The physical and chemical characteristics, as well as the emulsification properties of oxidized starch-xanthan gum composite nanoparticles (OGNP), were analyzed. The findings revealed that the OGNP retained spherical shape after the addition of XG, although their diameter increased from approximately 50-150 to 200-400 nm. Zeta potential decreased with XG content. Moreover, emulsions prepared from OGNP exhibited outstanding thermal stability, also showing enhanced storage stability. In addition, emulsions had different rheological properties at different pH values. The apparent viscosity and shear stress of emulsions under alkaline conditions were lower than that of neutral conditions. NaCl increased the apparent viscosity of OGNP-stabilized emulsions while reducing their thermal stability. The nanoparticles prepared in this study have efficient emulsification properties and can extend the application of OS.


Assuntos
Emulsões , Nanopartículas , Oxirredução , Polissacarídeos Bacterianos , Amido , Amido/química , Polissacarídeos Bacterianos/química , Nanopartículas/química , Emulsões/química , Viscosidade , Reologia , Tamanho da Partícula , Emulsificantes/química
16.
J Glaucoma ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38780279

RESUMO

PRCIS: The combination of surgical peripheral iridectomy, goniosynechialysis, and goniotomy is a safe and effective surgical approach for advanced primary angle-closure glaucoma without cataract. PURPOSE: To evaluate the efficacy and safety of surgical peripheral iridectomy (SPI), goniosynechialysis (GSL), and goniotomy (GT) in advanced primary angle-closure glaucoma (PACG) eyes without cataract. PATIENTS AND METHODS: A prospective multicenter observational study was performed for patients who underwent combined SPI, GSL, and GT for advanced PACG without cataract. Patients were assessed before and after the operation. Complete success was defined as achieving intraocular pressure (IOP) between 6-18 mm Hg with at least a 20% reduction compared to baseline, without the use of ocular hypotensive medications or reoperation. Qualified success adopted the same criteria but allowed medication use. Factors associated with surgical success were analyzed using logistic regression. RESULTS: A total of 61 eyes of 50 advanced PACG were included. All participants completed 12 months of follow-up. Thirty-six eyes (59.0%) achieved complete success, and 56 eyes (91.8%) achieved qualified success. Preoperative and postsurgical at 12 months mean IOPs were 29.7±7.7 and 16.1±4.8 mm Hg, respectively. The average number of ocular hypotensive medications decreased from 1.9 to 0.9 over 12 months. The primary complications included IOP spike (n=9), hyphema (n=7), and shallow anterior chamber (n=3). Regression analysis indicated that older age (odds ratio [OR]=1.09; P=0.043) was positively associated with complete success, while a mixed angle closure mechanism (OR=0.17; P=0.036) reduced success rate. CONCLUSIONS: The combination of SPI, GSL, and GT is a safe and effective surgical approach for advanced PACG without cataract. It has great potential as a first-line treatment option for these patients.

17.
Phys Chem Chem Phys ; 26(22): 16234-16239, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804520

RESUMO

Weak light detection is crucial in various practical applications such as night vision systems, flame monitoring, and underwater operations. Decreasing the dark current of a photodetector can effectively mitigate noises, consequently enhancing the signal-to-noise ratio and overall weak light detection performance. Herein, we demonstrate a 4H-SiC UV photodetector capable of detecting extremely weak UV light. This device comprises a photosensitive layer of 4H-SiC, two TiN electrodes and an atomically thin Al2O3 interfacial layer between TiN and the C surface of 4H-SiC. Under 360 nm UV light illumination, the proposed Al2O3 device demonstrates an ultra-low dark current of 18 fA, possibly benefiting from the effective passivation of interfacial carriers, and a boosted photo-to-dark current ratio of 6.7 × 107. Consequently, it achieves a weak-light detection limit as low as 31.8 pW cm-2, significantly outperforming the control device lacking Al2O3. When compared to previously reported SiC photodetectors, our Al2O3 device boasts an exceptional large linear dynamic range of 172 dB. Leveraging this, we construct a photodetector array capable of clearly imaging an object under ultra-weak light illumination below the 100 pW cm-2 level. The proposed photodetector represents a significant advancement in the development of highly sensitive image sensors for weak light detection.

18.
Oncoimmunology ; 13(1): 2358590, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812569

RESUMO

Chimeric antigen receptor (CAR) T cells have demonstrated outstanding therapeutic success in hematological malignancies. Yet, their efficacy against solid tumors remains constrained due to inadequate infiltration of cytotoxic T and CAR-T cells in the tumor microenvironment (TME), a factor correlated with poor prognosis in patients with solid tumors. To overcome this limitation, we engineered CAR-T cells to secrete CXCL10 and IL15 (10 × 15 CAR-T), which sustain T cell viability and enhance their recruitment, thereby amplifying the long-term cytotoxic capacity of CAR-T cells in vitro. In a xenograft model employing NUGC4-T21 cells, mice receiving 10 × 15 CAR-T cells showed superior tumor reduction and extended survival rates compared to those treated with second-generation CAR-T cells. Histopathological evaluations indicated a pronounced increase in cytotoxic T cell accumulation in the TME post 10 × 15 CAR-T cell treatment. Therefore, the synergistic secretion of CXCL10 and IL15 in these CAR-T cells enhances T cell recruitment and adaptability within tumor tissues, improving tumor control. This approach may offer a promising strategy for advancing CAR-T therapies in the treatment of solid tumors.


Assuntos
Quimiocina CXCL10 , Imunoterapia Adotiva , Interleucina-15 , Receptores de Antígenos Quiméricos , Neoplasias Gástricas , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Quimiocina CXCL10/metabolismo , Quimiocina CXCL10/genética , Neoplasias Gástricas/terapia , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos Quiméricos/genética , Humanos , Camundongos , Interleucina-15/genética , Interleucina-15/metabolismo , Imunoterapia Adotiva/métodos , Microambiente Tumoral/imunologia , Linhagem Celular Tumoral , Linfócitos T Citotóxicos/imunologia , Sobrevivência Celular , Feminino
19.
ISA Trans ; 151: 350-362, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38821849

RESUMO

This study proposes a novel tracking differentiator and applies it to the sliding-mode control (SMC) algorithm to address the unsatisfactory disturbance suppression and low tracking accuracy of magnetic levitation (maglev) systems. First, to assess performance in terms of filtering, tracking, and differentiation, an inverse hyperbolic sine function and a two-phase power function are introduced to improve the tracking differentiator. This can accelerate the global convergence speed, ensure smooth convergence at the equilibrium point, reduce system jitter, and enhance the noise-suppression ability of the system. The differentiator parameter-adjustment rules are derived from a system sweep. A comparison of the simulation results show that the proposed differentiator effectively suppresses noise and performs signal tracking and differentiation. Finally, the new differentiator is applied to the SMC of a maglev system. Simulation and experimental results show that the response speed of the maglev system under the SMC based on the new tracking differentiator is high, the jitter is effectively reduced, and the noise-suppression ability is improved.

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