Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Langmuir ; 40(6): 3035-3052, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38289641

RESUMO

The problems of low polishing efficiency and serious surface damage in the processing of silicon carbide (SiC) ceramics are well-known. In view of the above problems, a new method of photocatalytic vibration composite polishing (PVCP) combined with a compound control strategy was proposed. A vibration-assisted device was developed, and a compound control system was designed for the device to improve the trajectory tracking accuracy. Experiments were carried out to verify the effectiveness of the vibration-assisted device and the compound control system. In addition, methyl orange degradation and fading experiments, redox potential measurement experiments, and SiC ceramic surface hardness characterization experiments were carried out to reveal the effects of vibration and photocatalytic parameters on polishing solution oxidation and SiC ceramic surface mechanical properties. Finally, the effects of photocatalysis, vibration frequency, amplitude, and the compound control system on the polishing effect were analyzed. The results show that when the UV intensity is 100%, the polishing force is 3-4N, the vibration frequency is 400 Hz, the amplitude is 15 µm, and the surface roughness of SiC ceramics is reduced by about 11 nm after the introduction of the compound control system, which verifies the effectiveness of the combination of the compound control system and PVCP.

2.
BMC Pulm Med ; 24(1): 158, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561741

RESUMO

BACKGROUND: Anti-synthetase syndrome (ASS) is a group of rare clinical subtypes within inflammatory myopathies, predominantly affecting adult females. Instances of critical illness associated with ASS in children are even rarer. CASE PRESENTATION: We report the case of a 7-year-old boy finally diagnosed with ASS, combined with pneumomediastinum. He presented with intermittent fever persisting for 12 days, paroxysmal cough for 11 days, chest pain, and shortness of breath for 4 days, prompting admission to our hospital. Pre-admission chest CT revealed diffuse pneumomediastinum, subcutaneous pneumatosis in the neck and bilateral chest wall, consolidation, atelectasis, and reticular nodular shadowing in both lungs, as well as pericardial effusion and bilateral pleural effusions. Laboratory tests revealed a positive result for serum MP immunoglobulin M (MP-IgM) and MP immunoglobulin G (MP-IgG). The patient was initially diagnosed with mycoplasma pneumoniae (MP) infection, and following 3 days of antibiotic treatment, the patient's tachypnea worsened. Positive results in muscle enzyme antibody tests included anti-PL-12 antibody IgG, anti-Jo-1 antibody IgG, and anti-RO-52 antibody IgG. Ultrasonography detected moderate effusions in the right shoulder, bilateral elbow, and knee joints. Corticosteroids pulse therapy was initiated on the 27th day following disease onset, and continued for 3 days, followed by sequential therapy for an additional 12 days. The child was discharged on the 43rd day, and subsequent follow-up revealed a significant improvement in consolidation and interstitial lesions in both lungs. CONCLUSIONS: ASS in children may combine with rapidly progressive interstitial lung disease (RPILD) and pneumomediastinum. It is crucial to promptly identify concurrent immunologic abnormalities during the outbreak of MP, particularly when the disease exhibits rapid progression with ineffective conventional antibiotic therapy.


Assuntos
Enfisema Mediastínico , Criança , Humanos , Masculino , Antibacterianos/uso terapêutico , Imunoglobulina G , Pulmão , Enfisema Mediastínico/diagnóstico por imagem , Enfisema Mediastínico/etiologia , Enfisema Mediastínico/tratamento farmacológico , Tomografia Computadorizada por Raios X
3.
J Sci Food Agric ; 104(7): 3992-4003, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38323719

RESUMO

BACKGROUND: Resveratrol (Res) is promising food functional factor with favorable antioxidant and anti-inflammatory properties, although its poor water solubility and low bioavailability limit extensive application. Therefore, in combination with another promising polysaccharide (Mesona chinensis polysaccharides, MCP), Res-loaded food nanocarriers (ResNPs) were developed to increase its water solubility, bioactivity and targeting properties. ResNPs were then applied to alleviate dextran sulfate sodium (DSS)-induced ulcerative colitis. RESULTS: Resveratrol can be well encapsulated in MCP-based nanoparticles in an amorphous state, improving its water solubility. ResNPs showed pH-response controlled release behavior in the gastrointestinal tract and increased the enrichment of Res in the colon. In vivo experiments of ResNPs against DSS-induced ulcerative colitis (UC) revealed that ResNPs significantly improved UC symptoms, modulated intestinal inflammation and down-regulated oxidative stress levels compared to free Res. ResNPs also play an positive role with respect to inhibiting the mitogen-activated protein kinase pathway and promoting the expression of tight junction proteins. In addition, ResNPs improved the species composition and relative abundance of intestinal flora in UC mice, which effectively regulated the balance of intestinal flora and promoted the production of short-chain fatty acids. CONCLUSION: These results suggest that MCP-based nanoparticles can effectively improve the solubility of resveratrol and enhance its in vivo bioactivity. Moreover, the present study also provides a new strategy for the prevention and treatment of UC with food polyphenol. © 2024 Society of Chemical Industry.


Assuntos
Colite Ulcerativa , Colite , Nanopartículas , Zeína , Camundongos , Animais , Resveratrol/farmacologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Nanopartículas/química , Concentração de Íons de Hidrogênio , Água/farmacologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo
4.
Biochem Biophys Res Commun ; 681: 13-19, 2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-37742473

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a significant etiological factor in liver-related diseases, which can lead to severe consequences such as steatohepatitis, cirrhosis and death. Cdh1 is considered as a crucial protein involved in cell cycle regulation. The purpose of this study is to explore the biological role of Cdh1 in NAFLD. MATERIALS AND METHODS: NAFLD cell model was established, and L02 cells and AML12 cells were infected by shRNA lentivirus with Cdh1 knockdown in vitro, and the effect of Cdh1 deletion on cell lipid deposition was evaluated. The effects of Cdh1 deletion on Akt phosphorylation and PPAR/PGC-1α signaling pathway in L02 cells were examined. In addition, the NAFLD mouse model was constructed, and the conditional knockout mice of Cdh1 were selected to verify the results. RESULTS: In vitro experiments showed that the Cdh1 deletion enhanced cell lipid deposition. In vivo experiments showed that conditional knockdown of Cdh1 aggravated fatty degeneration and damage of liver in mice. Cdh1 deletion promotes Akt phosphorylation and inhibits PPAR/PGC-1α signaling pathway in L02 cells. Conditional knockout of Cdh1 down-regulates PPAR/PGC-1α signaling pathway in NAFLD mouse model. CONCLUSION: The deletion of Cdh1 may promote Akt phosphorylation by up-regulating Skp2 and inhibit the PPAR/PGC-1α signaling pathway. Cdh1 serves a protective function in the occurrence and progression of NAFLD.

5.
Immun Ageing ; 19(1): 21, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606877

RESUMO

BACKGROUND: Depression is considered to be an immune-related disease; however, previous studies have focused on inflammatory factors, and there is no conclusive conclusion on the relationships between immunoglobulins and depression. Therefore, the objective of this cross-sectional study was to evaluate the associations between immunoglobulins and depressive symptoms in Chinese older adults. RESULTS: The China Hainan Centenarian Cohort Study (CHCCS) provides a significant population-based sample of older adults in Hainan, China. A total of 1547 older adults were included in this study. A baseline survey was conducted using a structured questionnaire. Blood samples were obtained following standard procedures. The Geriatric Depression Scale (GDS-15) was used to evaluate depressive symptoms of the participants. This sample of older adults had a median age of 94.75 (range: 80-116) years, and the proportion of women was 72.07%. The prevalence of older adults with depressive symptoms was 20.36% (315 older adults). After adjusting for all covariates, we found that immunoglobulin A levels were positively associated with depression. The adjusted reliability of the association between immunoglobulin A and depression was 0.106 (beta) and 1.083 (odds ratio) (P < 0.05 for both). CONCLUSIONS: The present study provides epidemiological evidence that depression has significant associations with immunoglobulin A levels in older adults. Further research should be conducted on the effects of regulating immunoglobulin A to improve depressive symptoms.

6.
Appl Opt ; 61(28): 8190-8196, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256130

RESUMO

Ambient temperature is one of the important factors affecting the imaging quality of the optical system. Therefore, it is necessary to analyze the thermal-optical characteristics of the optical system when studying the imaging quality of the optical system. Taking the self-made aerial camera optical system as an example, this paper reports the use of the finite element software ANSYS to analyze the thermal stress of the aerial camera optical system, the use of the homogeneous coordinate transformation method to remove the rigid body displacement caused by the mirror surface, and the performance of a Zernike polynomial simulation on the processed surface data. Together, the Zernike coefficients obtained after the fitting are substituted into the ZEMAX optical software to express the surface shape obtained after deformation to analyze the changes in optical imaging quality under thermal environmental conditions. The results of the experiment show that when the working environmental temperature is 50°C, the (MTF) decreases from 0.371 to 0.315 and, when the working environmental temperature is -40∘C, the MTF decreases from 0.371 to 0.285. The comparison results of the experiment and simulation show that the environmental temperature is heating up or, under the condition of cooling, the imaging quality of the aerial camera will be reduced. The thermal-optical analysis method can be used to simulate the actual use conditions of the aerial camera optical system and predict the imaging quality change trend of the optical system. The method of thermo-optical analysis has important guiding significance for the design of an optical-mechanical system.

7.
Opt Express ; 29(12): 18108-18121, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34154077

RESUMO

Taking the area CCD optical system as a whole, the analysis methods of the influence of vibrations on its imaging quality have been relatively mature. However, external vibrations will cause different vibrations of optical components inside the opto-mechanical structure. The existing methods are not suitable for analyzing optical components with different vibrations and TDICCD imaging. This paper studies the influence of vibrations on the imaging quality of the integrated TDICCD aerial camera. The relationship between the vibration responses of structures and the imaging quality is established by mathematical models. First, a vibration beam trajectory model of the integrated TDICCD aerial camera is established for the first time using geometric optics and ray tracing. The deviations of the optical axis caused by vibrations in the object plane can be obtained. Then, this paper establishes a TDICCD vibration modulation transfer function model based on statistical moments. The vibration MTF of pixels of each column in the complex two-dimensional moving image captured by the TDICCD can be obtained through this model. Furthermore, a simulation imaging model of the integrated TDICCD aerial camera is established. The influence of vibrations on the imaging quality can be directly obtained through images. Finally, the accuracy of the models established in this paper is verified by multiple tests. The results show that the imaging quality of the integrated TDICCD aerial camera decreases rapidly with the increase of the acceleration excitation.

8.
Appl Opt ; 60(13): 3668-3676, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33983299

RESUMO

The ambient temperature is one of the important factors that affects the imaging quality of aspherical airborne camera. In order to evaluate the imaging quality of an airborne camera under the effect of ambient temperature and predict the influence of the ambient temperature on the modulation transfer function (MTF) of the airborne camera, on the basis of the imaging principle and the material properties of lenses of the airborne camera, this study integrates theoretical analysis, simulation analysis, and experimental tests to study the influence of ambient temperature on the imaging performance of airborne cameras. The imaging performance of an airborne camera is characterized by using the MTF. First, a mathematical model is presented to analyze the effect of ambient temperature on the MTF of the airborne camera. Then the simulation analysis and experiment tests are, respectively, proposed. The results of the mathematical model are compared, respectively, with the results of the simulation analysis and experimental test, and the comparison shows that the variation trends of the mathematical model results are in line with the simulation results and the experimental results, respectively. Therefore, the mathematical model presented in this study is effective for analyzing the influence of ambient temperature variation on the MTF of airborne cameras.

9.
Appl Opt ; 60(5): 1283-1293, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33690571

RESUMO

Aiming to investigate the connection between camera structure and optical systems, a comprehensive analysis needs to be performed for the airborne camera. An integrated analysis method was proposed to design and analyze optical and mechanical structures. Based on the designed small airborne camera, the impact of microvibration on the optical performance of the airborne camera was studied by integrated optomechanical analysis. In addition, the change of optical surface accuracy was analyzed. First, static and dynamic analysis of the designed airborne camera was performed to verify the stability of the camera structure and obtain the data for integrated optomechanical analysis. Then, a calculation method for rigid body displacement was proposed, and the impact of rigid body displacements on the optical system was analyzed. To evaluate the change of surface accuracy, the parameters root mean square (RMS) and peak to valley (PV) were calculated by fitting the surface distortion data. Based on the Zernike polynomial coefficients, the response of the optical system was calculated and analyzed utilizing ZEMAX to analyze the impact of microvibration on the optical performance of the airborne camera. The analysis results show that microvibration has no significant impact on optical performance of the designed small airborne camera. Finally, the analysis results were verified through experiments.

10.
Int J Cancer ; 146(5): 1268-1280, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31463974

RESUMO

Gastric cancer (GC) is the third leading cause of cancer deaths and the fourth most prevalent malignancy worldwide. The high incidence and mortality rates of gastric cancer result from multiple factors such as ineffective screening, diagnosis, and limited treatment options. In our study, we sought to systematically identify predictive molecular networks and key regulators to elucidate complex interacting signaling pathways in GC. We performed an integrative network analysis of the transcriptomic data in The Cancer Genome Atlas (TCGA) gastric cancer cohort and then comprehensively characterized the predictive subnetworks and key regulators by the matched genetic and epigenetic data. We identified 221 gene subnetworks (modules) in GC. The most prognostic subnetworks captured multiple aspects of the tumor microenvironment in GC involving interactions among stromal, epithelial and immune cells. We revealed the genetic and epigenetic underpinnings of those subnetworks and their key transcriptional regulators. We computationally predicted and experimentally validated specific mechanisms of anticancer effects of GKN2 in gastric cancer proliferation and invasion in vitro. The network models and the key regulators of the tumor microenvironment in GC identified here pave a way for developing novel therapeutic strategies for GC.


Assuntos
Proteínas de Transporte/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Neoplasias Gástricas/genética , Microambiente Tumoral/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Proliferação de Células/genética , Estudos de Coortes , Biologia Computacional , Conjuntos de Dados como Assunto , Intervalo Livre de Doença , Epigênese Genética , Feminino , Gastrectomia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Estômago/patologia , Estômago/cirurgia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Adulto Jovem
11.
Appl Opt ; 59(27): 8196-8204, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32976401

RESUMO

Aerial cameras are widely used in a number of fields. Various mechanical errors cannot be ignored with the improvement of imaging quality requirements. This paper introduces an integrated time delay integration charge coupled device (TDICCD) aerial camera. Compared with traditional aerial cameras, it can significantly improve shooting efficiency and imaging quality under similar load conditions. This paper first analyzes mechanical errors of the integrated TDICCD aerial camera and establishes a pointing error model based on ray tracing, then performs model parameter identification using a genetic algorithm, and completes error compensation. Finally, test results demonstrate that the compensation of the pointing error can effectively improve pointing accuracy of the optical axis. The mean of comprehensive errors was reduced by an order of magnitude, and the variance of comprehensive errors was reduced from 1.0075(mm)2 to 0.0543(mm)2.

12.
Surg Endosc ; 30(11): 5099-5107, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27005293

RESUMO

INTRODUCTION: Endoscopic submucosal dissection (ESD) has been used for the treatment of gastric submucosal tumors (SMTs). This study aims to compare clinical outcomes of ESD versus laparoscopic wedge resection (LWR) for gastric SMTs. METHODS: This is a retrospective cohort study. Patients with SMTs who underwent ESD or LWR were enrolled in this study at a university-affiliated hospital from January 2010 to October 2015. Preoperative endoscopic ultrasound and computed tomography were performed to determine origin of layer and growth pattern. Clinical outcomes including baseline demographics, tumor size, operation time, blood loss, hospital stay, cost, pathology and postoperative complications were compared. RESULTS: From January 2010 to October 2015, 68 patients with SMTs received ESD and 47 patients with SMTs received LWR. There was no difference in age, gender, body mass index, origin of layer and proportion with symptoms between ESD group and LWR group. However, tumor size was significantly larger in the LWR group (37.1 mm) than in the ESD group (25.8 mm, P = 0.041). For patients with tumors smaller than 20 mm, ESD was associated with shorter mean operation time (89.7 ± 23.5 vs 117.6 ± 23.7 min, P = 0.043), less blood loss (4.9 ± 1.7 vs 72.3 ± 23.3 ml, P < 0.001), shorter length of hospital stay (3.6 ± 1.9 vs 6.9 ± 3.7 days, P = 0.024) and lower cost (2471 ± 573 vs 4498 ± 1257 dollars, P = 0.031) when compared with LWR. For patients with tumors between 20 mm and 50 mm, ESD was associated with shorter mean operation time (99.3 ± 27.8 vs 125.2 ± 31.5 min, P = 0.039), less blood loss (10.1 ± 5.3 vs 87.6 ± 31.3 ml, P < 0.001), shorter length of hospital stay (4.0 ± 1.7 vs 7.3 ± 4.5 days, P = 0.027) and lower cost (2783 ± 601 vs 4798 ± 1343 dollars, P = 0.033) when compared with LWR. There were no significant differences in terms of rates of en bloc resection, complete resection and complication and histological diagnosis regardless of tumor size. CONCLUSIONS: ESD can achieve similar oncological outcomes when compared with surgery for treatment of gastric SMT smaller than 50 mm.


Assuntos
Tumores do Estroma Gastrointestinal/cirurgia , Músculo Liso/patologia , Neoplasias Gástricas/cirurgia , Estudos de Coortes , Ressecção Endoscópica de Mucosa/métodos , Feminino , Mucosa Gástrica/cirurgia , Gastroscopia/métodos , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento
13.
Cancer Causes Control ; 26(9): 1245-55, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26081426

RESUMO

PURPOSE: We aim to investigate the association between angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) therapy and colorectal cancer (CRC) by conducting a systematic review with meta-analysis. METHODS: Literature was searched on PubMed, Scopus, and the Cochrane library to identify relevant studies evaluating ACEIs/ARBs therapy and risk of CRC incidence or survival of CRC patients. Pooled risk ratio (RR) with 95% confidence intervals was calculated for the association between ACEIs/ARBs and CRC risk and mortality. RESULTS: Eleven observational studies were included in the systematic review. A meta-analysis of six studies totaling 113,048 individuals indicated a 6% decreased risk of CRC in ACEIs/ARBs users compared to non-users (95% CI 0.89-0.98). In the four case-control studies, individuals using ACEIs/ARBs were associated with a 6% decreased risk of CRC (95% CI 0.90-0.99). The meta-analysis of three studies investigating the relationship between ACEIs/ARBs and survival of CRC did not show a significantly decreased mortality in ACEIs/ARBs users (RR 0.81, 95% CI 0.60-1.09). Seven studies evaluated the dose-response relationship between ACEIs/ARBs therapy and CRC, and two of them showed that the association was related to longer duration and higher dose. CONCLUSIONS: CEIs/ARBs therapy might be associated with a reduce risk of CRC development, but whether use of these medications improves the outcomes of CRC remains unknown. Large-scale and more robust studies are needed to further explore this association.


Assuntos
Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Humanos , Hipertensão/tratamento farmacológico , Incidência , Risco
14.
Front Bioeng Biotechnol ; 12: 1342120, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38433824

RESUMO

As an outstanding visual system for insects and crustaceans to cope with the challenges of survival, compound eye has many unique advantages, such as wide field of view, rapid response, infinite depth of field, low aberration and fast motion capture. However, the complex composition of their optical systems also presents significant challenges for manufacturing. With the continuous development of advanced materials, complex 3D manufacturing technologies and flexible electronic detectors, various ingenious and sophisticated compound eye imaging systems have been developed. This paper provides a comprehensive review on the microfabrication technologies, photoelectric detection and functional applications of miniature artificial compound eyes. Firstly, a brief introduction to the types and structural composition of compound eyes in the natural world is provided. Secondly, the 3D forming manufacturing techniques for miniature compound eyes are discussed. Subsequently, some photodetection technologies for miniature curved compound eye imaging are introduced. Lastly, with reference to the existing prototypes of functional applications for miniature compound eyes, the future development of compound eyes is prospected.

15.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38407492

RESUMO

Energy, as an indispensable part of human life, has been a hot topic of research among scholars. The water kinetic energy generated by ocean currents, as a kind of clean energy, has high utilization rate, high power generation potential, and a broad prospect of powering microelectronic devices. As a result, the water kinetic piezoelectric energy harvester (WKPEH) has made significant progress in powering ocean sensors by harvesting ocean currents. This paper provides a comprehensive review of technologies that have been used in recent years to harvest energy from marine fluids using WKPEH. Detailed study of the energy harvesting mechanism of WKPEH. WKPEH can use the flutter-induced vibrations, vortex-induced vibrations, and wake oscillation principles to harvest water kinetic energy. The structural characteristics and output performance of each mechanism are also discussed and compared, and finally, a prospect on WKPEH is given.

16.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38607263

RESUMO

Wearable piezoelectric energy harvesters (WPEHs) have gained popularity and made significant development in recent decades. The harvester is logically built by the movement patterns of various portions of the human body to harvest the movement energy and immediately convert it into usable electrical energy. To directly power different microelectronic devices on the human body, a self-powered device that does not require an additional power supply is being created. This Review provides an in-depth review of WPEHs, explaining the fundamental concepts of piezoelectric technology and the materials employed in numerous widely used piezoelectric components. The harvesters are classed according to the movement characteristics of several portions of a person's body, such as pulses, joints, skin, and shoes (feet). Each technique is introduced, followed by extensive analysis. Some harvesters are compared, and the benefits and drawbacks of each technique are discussed. Finally, this Review presents future goals and objectives for WPEH improvement, and it will aid researchers in understanding WPEH to the point of more efficient wireless energy delivery to wearable electronic components.

18.
Heliyon ; 10(4): e26609, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404806

RESUMO

Objectives: To investigate the characteristics of brain structure in children with focal cortical dysplasia (FCD)-induced pharmacoresistant epilepsy, and explore the potential mechanisms of cognitive impairment from the view of gray matter alteration. Methods: 25 pharmacoresistant pediatric patients with pathologically confirmed focal cortical dysplasia (FCD), and 25 gender-matched healthy controls were included in this study. 3.0T MRI data and intelligence tests using the Wechsler Intelligence Scale for Children-Forth Edition (WISC-IV) were generated for all subjects. Voxel-based morphometry (VBM)-diffeomorphic anatomical registration through exponentiated lie algebra (DARTEL) and surface-based morphometry (SBM) analyses were performed to analyze gray matter volume and cortical structure. Two-sample t-tests were used to compare the differences in gray matter volume (P<0.05, FWE) and cortical thickness (P<0.001, FWE) between the two groups. Also, the Spearman rank correlation analyses were employed to determine the relationship between structural alterations and neuropsychological results. Results: The WISC-IV scores of the FCD group were significantly lower than those of the HC group in terms of full-scale intelligence quotient (FSIQ), verbal comprehension index (VCI), perceptual reasoning index (PRI), working memory index (WMI), and processing speed index (PSI) (all P<0.01). Compared with the HC group, in the FCD group, the gray matter volume (GMV) reduced significantly in the left cerebellum_8, cerebellum_Crus2, and bilateral thalamus (P<0.05, FWE); the GMV increased in the bilateral medial frontal gyrus, right precuneus, and left inferior temporal gyrus (P<0.05, FWE), and the cortical thickness increased in the bilateral frontal, parietal, and temporal areas (P<0.001, FWE). Correlation analyses showed that the age of seizure onset had positive correlations with the WISC-IV scores significantly. Meanwhile, the cortex thicknesses of the left pars opercularis gyrus, left middle temporal gyrus, and right inferior temporal gyrus had negative correlations with the WISC-IV scores significantly. Conclusion: FCD patients showed subtle structural abnormalities in multiple brain regions, with significant involvement of the primary visual cortex and language function cortex. And we also demonstrated a crucial correlation between gray matter structural alteration and cognitive impairment.

19.
ScientificWorldJournal ; 2013: 641269, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24163627

RESUMO

Accurately modeling the dynamic behaviors of fast tool servo (FTS) is one of the key issues in the ultraprecision positioning of the cutting tool. Herein, a quasiphysics intelligent model (QPIM) integrating a linear physics model (LPM) and a radial basis function (RBF) based neural model (NM) is developed to accurately describe the dynamic behaviors of a voice coil motor (VCM) actuated long range fast tool servo (LFTS). To identify the parameters of the LPM, a novel Opposition-based Self-adaptive Replacement Differential Evolution (OSaRDE) algorithm is proposed which has been proved to have a faster convergence mechanism without compromising with the quality of solution and outperform than similar evolution algorithms taken for consideration. The modeling errors of the LPM and the QPIM are investigated by experiments. The modeling error of the LPM presents an obvious trend component which is about ±1.15% of the full span range verifying the efficiency of the proposed OSaRDE algorithm for system identification. As for the QPIM, the trend component in the residual error of LPM can be well suppressed, and the error of the QPIM maintains noise level. All the results verify the efficiency and superiority of the proposed modeling and identification approaches.


Assuntos
Redes Neurais de Computação , Algoritmos
20.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37655994

RESUMO

This paper presents a piezoelectric energy harvesting device applicable to wireless mouse (WM-PEH). Adding magnetic force to the excitation piezoelectric generating unit makes the impact better and more pronounced. The polygonal roller can increase the excitation frequency of the piezoelectric generating unit and broaden the energy collection range and capability of the WM-PEH. The theoretical and simulation analysis of WM-PEH was carried out in this paper. The effects of the length ratio of the exciter rod to the support frame and the circular impact area on the output characteristics of the prototype were discussed in the experiment. When the length ratio of the exciter rod and the support rod is 3:1, the activity increment of the exciter rod is the largest, and the maximum output voltage can reach 42 V and the maximum output power is 22.43 mW when it acts on a circular generator set with a radius of 1.5 mm. The design of the device is highly integrated with the wireless mouse that is widely used, and the piezoelectric energy harvesting mechanism and the wireless mouse are perfectly combined, which provides a scientific basis for the subsequent development of a self-powered wireless mouse.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA