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1.
Cancer Genet ; 284-285: 48-57, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38729078

RESUMEN

Although lncRNAs are recognized to contribute to the development of oral squamous-cell carcinoma (OSCC), their exact function in invasion and cell migration is not clear. In this research, we explored the molecular and cellular mechanisms of FOXD2-AS1 in OSCC. Prognostic and bioinformatics analyses were used to test for the differential expression of FOXD2-AS1-PLOD1. Following FOXD2-AS1 suppression or overexpression, changes in cell viability were measured using the CCK-8 test; changes in cell migration and invasion abilities were measured using the migration and the Transwell assay. The expression of associated genes and proteins was found using Western blot and RT-qPCR. Analysis of luciferase reporter genes was done to look for regulatory connections between various molecules. The FOXD2-AS1-PLOD1 pair, which was highly expressed in OSCC, was analyzed and experimentally verified to be closely related to the prognosis of OSCC, and a nomogram model and correction curve were constructed. The inhibition of FOXD2-AS1 resulted in the reduction of cell activity, migration, invasion ability and changes in genes related to invasion and migration. In vivo validation showed that inhibition of FOXD2-AS1 expression slowed tumor growth, and related proteins changed accordingly. The experiments verified that FOXD2-AS1 negatively regulated miR-185-5 p and that miR-185-5 p negatively regulated PLOD1. In addition, it was found that the expression of PLOD1, p-Akt and p-mTOR proteins in OSCC cells was reduced by the inhibition of FOXD2-AS1, and FOXD2-AS1 and PLOD1 were closely related to the Akt/mTOR pathway. Increased expression of FOXD2-AS1 promotes OSCC growth, invasion and migration, which is important in part by targeting miR-185-5 p/PLOD1/Akt/mTOR pathway activity.

2.
PLoS One ; 19(5): e0302742, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38768144

RESUMEN

Zeaxanthin dipalmitate (ZD) is a chemical extracted from wolfberry that protects degenerated photoreceptors in mouse retina. However, the pure ZD is expensive and hard to produce. In this study, we developed a method to enrich ZD from wolfberry on a production line and examined whether it may also protect the degenerated mouse retina. The ZD-enriched wolfberry extract (ZDE) was extracted from wolfberry by organic solvent method, and the concentration of ZD was identified by HPLC. The adult C57BL/6 mice were treated with ZDE or solvent by daily gavage for 2 weeks, at the end of the first week the animals were intraperitoneally injected with N-methyl-N-nitrosourea to induce photoreceptor degeneration. Then optomotor, electroretinogram, and immunostaining were used to test the visual behavior, retinal light responses, and structure. The final ZDE product contained ~30mg/g ZD, which was over 9 times higher than that from the dry fruit of wolfberry. Feeding degenerated mice with ZDE significantly improved the survival of photoreceptors, enhanced the retinal light responses and the visual acuity. Therefore, our ZDE product successfully alleviated retinal morphological and functional degeneration in mouse retina, which may provide a basis for further animal studies for possible applying ZDE as a supplement to treat degenerated photoreceptor in the clinic.


Asunto(s)
Modelos Animales de Enfermedad , Lycium , Ratones Endogámicos C57BL , Células Fotorreceptoras de Vertebrados , Extractos Vegetales , Degeneración Retiniana , Zeaxantinas , Animales , Lycium/química , Degeneración Retiniana/tratamiento farmacológico , Degeneración Retiniana/patología , Ratones , Extractos Vegetales/farmacología , Extractos Vegetales/química , Zeaxantinas/farmacología , Células Fotorreceptoras de Vertebrados/efectos de los fármacos , Células Fotorreceptoras de Vertebrados/patología , Electrorretinografía , Retina/efectos de los fármacos , Retina/patología , Retina/metabolismo , Visión Ocular/efectos de los fármacos , Masculino , Xantófilas/farmacología
3.
Sci Rep ; 14(1): 11451, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769443

RESUMEN

The SMALL ACIDIC PROTEIN (SMAP) gene is evolutionarily indispensable for organisms. There are two copies of the SMAP gene in the Arabidopsis thaliana genome, namely, SMAP1 and SMAP2. The function of SMAP2 is similar to that of SMAP1, and both can mediate 2,4-D responses in the root of Arabidopsis. This study cloned the AtSMAP2 genetic promoter sequence. Two promoter fragments of different lengths were designed according to the distribution of their cis-acting elements, and the corresponding ß- glucuronidase (GUS) expression vector was constructed. The expression activity of promoters of two lengths, 1993 bp and 997 bp, was studied by the genetic transformation in Arabidopsis. The prediction results of cis-acting elements in the promoter show that there are many hormone response elements in 997 bp, such as three abscisic acid response elements ABRE, gibberellin response elements P-box and GARE-motif and auxin response element AuxRR-core. Through GUS histochemical staining and qRT‒PCR analysis, it was found that the higher promoter activity of PAtSMAP2-997, compared to PAtSMAP2-1993, drove the expression of GUS genes at higher levels in Arabidopsis, especially in the root system. The results provide an important basis for subsequent studies on the regulation of AtSMAP2 gene expression and biological functions.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Regiones Promotoras Genéticas , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Plantas Modificadas Genéticamente/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Elementos de Respuesta
4.
Materials (Basel) ; 17(5)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38473554

RESUMEN

Cement-stabilization of weak and soft soils is an efficient way for ground improvement. Traditional Portland cement remains the most popular cementitious material in practice, and thus, a proper dosage design of cement-stabilized soil is of practical interest to meet the sustainable engineering requirements and to remedy environmental concerns. Based on the unconfined compression test of cement-stabilized Qiantang River silty clay, the effects of cement content, mixing moisture content, mixing-water-to-cement ratio, and curing time on the unconfined compressive strength were investigated. The results show that the mixing-water-to-cement ratio can comprehensively characterize the effects of cement content and water content on the unconfined compressive strength of the cement-stabilized clay. A prediction method for the unconfined compressive strength of cement-stabilized Qiantang River silty clay has been proposed with considerations for mixing-water-to-cement ratio and curing time. By comparing the experimental data of the present study with the existing literature data, it is found that there is a unified relationship between the unconfined compressive strength and the mixing-water-to-cement ratio of cement-stabilized Qiantang River silty clay, kaolin, Singapore marine clay, and Bangkok clay under the same curing time. The prediction method recommended by the standard may overestimate the unconfined compressive strength of cement-stabilized Qiantang River silty clay cured for 90 days.

6.
Biotechnol Biofuels Bioprod ; 17(1): 24, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360689

RESUMEN

BACKGROUND: Genome-scale screening can be applied to efficiently mine for unknown genes with phenotypes of interest or special functions. It is also useful to identify new targets for engineering desirable properties of cell factories. RESULTS: Here, we designed a new approach for genome-scale transcription activation using non-homologous end joining (NHEJ)-mediated integration in Yarrowia lipolytica. We utilized this approach to screen for genes that, upon activation, confer phenotypes including improved acetic acid tolerance and xylose metabolism. The candidates were validated using gene overexpression, and functional changes including improved growth performance under multiple stressors and activated pentose metabolism were identified. CONCLUSIONS: This study provides a simple and effective approach to randomly activate endogenous genes and mine for key targets associated with phenotypes of interest. The specific gene targets identified here will be useful for cell factory construction and biorefining lignocellulose.

7.
Heliyon ; 10(3): e25527, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38333804

RESUMEN

Statement of problem: Bibliometric analysis methods were used to evaluate pediatric dental sedation research and to identify topical hotspots using quantitative and qualitative methodologies. Purpose: To conduct bibliometric analysis on the retrieved data and to foresee the development of trends and hotspots in this research area. Material and methods: We retrieved appropriate research articles from the Web of Science Core Collection on January 1, 2023. VOSviewer, Citespace and the Bibliometrics website were used to conduct bibliometric analysis on the retrieved data. GraphPad Prism 10.0 (GraphPad, San Diego, CA, USA) was used to conduct the statistical analysis. Results: A total of 396 publications on pediatric sedation in dentistry, published between 1993 and 2022, were retrieved from online databases. The USA published most papers. Furthermore, the most frequent countries who cooperated were the USA and Canada. Six of the top ten publishing establishments were USA based. Papers on the research have appeared primarily in the journals of Dentistry and Anesthesiology. Keyword co-occurrence and co-citation cluster analysis revealed that the most common topics mainly were: dental anxiety; conscious sedation; dental caries; midazolam; propofol; hypoxemia. Conclusions: During the three decades, the focus of pediatric sedation research has been on drugs, dental anxiety and procedural sedation. Keyword burst detection indicated that procedural sedation; adverse event; respiratory depression is an emerging research hotspot.

8.
Bioresour Technol ; 394: 130294, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38185448

RESUMEN

Catalytic pyrolysis is an effective means for high-value utilization of biomass. This study investigated the effect of solid base catalysts (CaO, calcium aluminate catalysts CaAl-1, CaAl-2, CaAl-3), acid zeolite catalysts (ZSM-5, Fe/ZSM-5, Co/ZSM-5, Ni/ZSM-5, Cu/ZSM-5, Zn/ZSM-5) and base-acid tandem catalysts on pine sawdust pyrolysis using Py-GC/MS. Acid zeolite catalysts exhibited robust deoxidation and aromatization capabilities, favoring aromatics, while solid base catalysts yielded more phenols and ketones. Among the solid base catalysts, CaAl-3 (CaO-Ca12Al14O33) showed comparable deoxygenation activity to CaO and optimal aromatic selectivity with structural stability. Zn/ZSM-5 excelled in deoxygenation and aromatic selectivity (70.42%) among metal-modified ZSM-5 catalysts. Base-acid tandem catalysis promoted the formation of aliphatics and BTX (benzene, toluene, xylene) while suppressing polycyclic aromatics. The highest BTX content (44.35%) was achieved with CaO-Ca12Al14O33&Zn/ZSM-5 tandem catalysts in a 1:3 ratio. This work demonstrates base-acid tandem catalysis as a promising approach for converting pine sawdust into valuable chemicals.


Asunto(s)
Pinus , Zeolitas , Pirólisis , Zeolitas/química , Catálisis , Tolueno , Benceno , Biomasa
9.
Otolaryngol Head Neck Surg ; 170(3): 845-852, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37870231

RESUMEN

OBJECTIVE: To identify the characteristics of the time-point distribution of the occurrence of hypopharyngeal-proximal reflux episodes (HREs) in elderly and younger patients with laryngopharyngeal reflux (LPR). STUDY DESIGN: Retrospective cohort study. SETTING: Analysis of data from patients with LPR-related symptoms and 24-hour hypopharyngeal-esophageal multichannel intraluminal impedance-pH (24-hour HEMII-pH) monitoring from February 2017 to September 2022 at Sixth Medical Center of PLA General Hospital. METHODS: Patients were divided into 2 age groups: the elderly group (>60 years) and the younger group (≤60 years). The time series of HREs and meals within 24 hours were analyzed based on HEMII-pH. RESULTS: A total of 305 patients were included (126 elderly patients). In younger patients, except for nonacid-gas HREs, the incidence of the remaining types of HREs tended to increase within 2 hours after meals, especially after dinner. The incidence of all types of HREs pre- and postmeal was not significantly different in the elderly group (χ2 = 0.080, P = .777). The incidence of nighttime HREs in elderly patients was statistically higher than in younger patients (6.23% vs 3.96%, P = .030), particularly acid-/nonacid-liquid HREs. CONCLUSION: HREs tend to increase within 2 hours after meals in younger LPR patients, except for nonacid-gas HREs. In elderly LPR patients, the incidence of all types of HREs pre- and postmeal were not significantly different, and nighttime fluid HREs was more prone to occur than in younger patients.


Asunto(s)
Reflujo Laringofaríngeo , Humanos , Anciano , Persona de Mediana Edad , Reflujo Laringofaríngeo/epidemiología , Reflujo Laringofaríngeo/diagnóstico , Estudios Retrospectivos , Monitorización del pH Esofágico , Hipofaringe , Impedancia Eléctrica
10.
Plant Sci ; 339: 111930, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38007196

RESUMEN

Switchgrass (Panicum virgatum L.) plays a pivotal role as a bioenergy feedstock in the production of cellulosic ethanol and contributes significantly to enhancing ecological grasslands and soil quality. The utilization of non-coding RNAs (ncRNAs) has gained momentum in deciphering the intricate genetic responses to abiotic stress in various plant species. Nevertheless, the current research landscape lacks a comprehensive exploration of the responses of diverse ncRNAs, including long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs), to drought stress in switchgrass. In this study, we employed whole transcriptome sequencing to comprehensively characterize the expression profiles of both mRNA and ncRNAs during episodes of drought stress in switchgrass. Our analysis identified a total of 12,511 mRNAs, 59 miRNAs, 38 circRNAs, and 368 lncRNAs that exhibited significant differential expression between normal and drought-treated switchgrass leaves. Notably, the majority of up-regulated mRNAs displayed pronounced enrichment within the starch and sucrose metabolism pathway, as validated through KEGG analysis. Co-expression analysis illuminated that differentially expressed (DE) lncRNAs conceivably regulated 1308 protein-coding genes in trans and 7110 protein-coding genes in cis. Furthermore, both cis- and trans-target mRNAs of DE lncRNAs exhibited enrichment in four common KEGG pathways. The intricate interplay between lncRNAs and circRNAs with miRNAs via miRNA response elements was explored within the competitive endogenous RNA (ceRNA) network framework. As a result, we constructed elaborate regulatory networks, including lncRNA-novel_miRNA480-mRNA, lncRNA-novel_miRNA304-mRNA, lncRNA/circRNA-novel_miRNA122-PvSS4, and lncRNA/circRNA-novel_miRNA14-PvSS4, and subsequently validated the functionality of the target gene, starch synthase 4 (PvSS4). Furthermore, through the overexpression of PvSS4, we ascertained its capacity to enhance drought tolerance in yeast. However, it is noteworthy that PvSS4 did not exhibit any discernible impact under salt stress conditions. These findings, as presented herein, not only contribute substantively to our understanding of ceRNA networks but also offer a basis for further investigations into their potential functions in response to drought stress in switchgrass.


Asunto(s)
MicroARNs , Panicum , ARN Largo no Codificante , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Panicum/genética , Panicum/metabolismo , ARN Largo no Codificante/genética , Sequías , Perfilación de la Expresión Génica , MicroARNs/genética , MicroARNs/metabolismo , Redes Reguladoras de Genes
11.
J Voice ; 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37951814

RESUMEN

OBJECTIVES: To explore the relationship between arytenoid cartilage sclerosis and a history of previous surgical resection in patients with laryngeal contact granuloma. METHODS: 167 patients with laryngeal contact granuloma treated from March 2016 to December 2018 were studied. The high-resolution computed tomography (HRCT) data of the sclerosis of arytenoid cartilage is divided into asymmetric sclerosis, bilateral sclerosis, and no sclerosis according to the range of sclerosis. The proportions of various ranges of sclerosis in two subgroups of patients were compared to patients with and without a history of previous surgical resection. RESULTS: The arytenoid cartilage sclerosis rate of 167 patients was 69.46%. The exact probability method showed that P < 0.001, suggesting that the distribution of arytenoid cartilage sclerosis was different in patients with and without a history of previous surgical resection, and there was a moderate correlation between the extent of arytenoid sclerosis and history of previous surgical resection (Cramer's V = 0.436, P < 0.001). There were 18 cases of bilateral sclerosis in patients with a history of previous surgical resection, of which 50% had contralateral recurrence after combined therapy (proton pump inhibitor (PPI) and glucocorticoid injection into granuloma via the thyrohyoid membrane approach), accounting for 75% of recurrence after combined therapy. CONCLUSION: Surgery promotes the expansion of arytenoid sclerosis, Patients with bilateral arytenoid sclerosis are prone to recurrence of contralateral laryngeal contact granuloma.

12.
J Voice ; 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37833112

RESUMEN

OBJECTIVE: To investigate the relationship between laryngopharyngeal reflux (LPR) and obstructive sleep apnea (OSA). METHODS: Patients diagnosed with OSA who were hospitalized in the Department of Otolaryngology-Head and Neck Surgery from November 2021 to April 2022 were selected, and male patients with non-OSA during the same period were selected as the control group. Patients who participated in the study completed the Reflux Symptom Index (RSI), the Reflux Finding Sign (RFS), and 24-hour multichannel intraluminal impedance-pH (MII-pH) monitoring. RSI, RFS, and outcomes of 24 hour-MII-pH monitoring were compared between the OSA group and the control group. RESULTS: A total of 86 patients were enrolled, of whom 49 were OSA patients and 37 were non-OSA patients. The positive rate of LPR (97.96% vs 75.68%) and the median number of LPR episodes (9 vs 5) were significantly higher in OSA patients than in non-OSA patients (P < 0.01, P < 0.05, respectively). A logistic regression model including body mass index, alcohol consumption, and the presence of OSA showed that having OSA was a risk factor for the occurrence of LPR (P < 0.05, OR [odds ratio] = 9.995, 95% CI [confidence interval] 1.084-92.181). There were correlations between Apnea-Hypopnea Index and the number of non-acid LPR episodes and the number of alkaline LPR episodes (r = 0.243, P < 0.05, r = 0.274, P < 0.05, respectively). CONCLUSIONS: Having OSA is a risk factor for LPR, and LPR episodes occur more frequently in patients with OSA compared to those without OSA. When OSA is comorbid with LPR, the occurrence of alkaline LPR, such as bile reflux, should be a concurrent concern.

14.
Parkinsonism Relat Disord ; 114: 105803, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37567063

RESUMEN

OBJECTIVES: Orthostatic hypotension (OH) is one of the most important autonomic features of multiple system atrophy (MSA). This study was established to confirm the correlation between lipid levels and OH in MSA. METHODS: A total of 580 patients with probable or possible MSA from neurological wards in six hospitals in Tianjin, Beijing, Hebei Province, and Henan Province, China, were included in this study. The tilt test or stand test was used to assess the severity of OH. Lipid contents, including total cholesterol, low-density-lipoprotein cholesterol (LDL-C), high-density-lipoprotein cholesterol (HDL-C), and triglyceride were evaluated. RESULTS: Serum levels of total cholesterol, LDL-C, and triglyceride in MSA-OH patients were significantly lower than those in MSA without OH. The risks of OH were significantly higher in the lowest quartiles of triglyceride and LDL-C than in the highest quartiles, after adjusting for confounders (OR = 2.17, 95% CI: 1.23-3.82, P = 0.008 and OR = 2.02, 95% CI: 1.16-3.47, P = 0.012). The risk of severe OH was significantly higher in the lowest quartile and the second quartile of triglyceride than in the highest quartile after adjusting for confounders (OR = 2.16, 95% CI: 1.20-3.87, P = 0.010 and OR = 2.25, 95% CI: 1.24-4.07, P = 0.007). Moreover, the risk of OH was significantly higher in the lowest quartile, and the third quartile of TC than in the highest quartile after adjusting for confounders (OR = 2.04, 95% CI: 1.18-3.52, P = 0.010 and OR = 2.06, 95% CI: 1.19-3.56, P = 0.010). CONCLUSION: Low levels of TC, LDL-C, and triglyceride increased the risk of OH in MSA. A low level of triglyceride predicted severe OH in MSA.


Asunto(s)
Hipotensión Ortostática , Atrofia de Múltiples Sistemas , Humanos , Atrofia de Múltiples Sistemas/complicaciones , Hipotensión Ortostática/complicaciones , LDL-Colesterol , Triglicéridos , HDL-Colesterol
15.
PeerJ Comput Sci ; 9: e1473, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37547398

RESUMEN

Path planning is a critical technology that could help mobile robots accomplish their tasks quickly. However, some path planning algorithms tend to fall into local optimum in complex environments. A path planning method using a modified Harris hawks optimization (MHHO) algorithm is proposed to address the problem and improve the path quality. The proposed method improves the performance of the algorithm through multiple strategies. A linear path strategy is employed in path planning, which could straighten the corner segments of the path, making the obtained path smooth and the path distance short. Then, to avoid getting into the local optimum, a local search update strategy is applied to the HHO algorithm. In addition, a nonlinear control strategy is also used to improve the convergence accuracy and convergence speed. The performance of the MHHO method was evaluated through multiple experiments in different environments. Experimental results show that the proposed algorithm is more efficient in path length and speed of convergence than the ant colony optimization (ACO) algorithm, improved sparrow search algorithm (ISSA), and HHO algorithms.

16.
Heliyon ; 9(6): e16327, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37287617

RESUMEN

Purpose: Infectious skin diseases are a type of inflammatory skin lesions caused by pathogenic microorganisms. Because of the uncertainty of methodology, the skin infection model usually have low replication rate and lack of good evaluation system. We aimed to establish multi-index and comprehensive evaluation method for Staphylococcus aureus (S.aureus) skin-infection models through Analytic hierarchy process (AHP) and Delphi method, and screen high quality animal models through it. Materials and methods: Firstly, the evaluation indicators of skin infection were collected basing on literature research. The weight of the evaluation indicators were decided according to AHP and Delphi method. Then different ulcer models (mouse or rat) infected by S. aureus were selected as the research objects. Results: The evaluation indicators were classified into four groups of criteria (including ten sub-indicators) and given different weights, physical sign changes (0.0518), skin lesion appearance (0.2934), morphological observation (0.3184), etiological examination (0.3364). Through the evaluation system, we screened and found that the mouse ulcer model which caused by a round wound and 1.0 × 1010 CFU/mL (0.1 mL) bacterial concentration got the highest comprehensive score, and also found that the model which caused by a 1.5 cm-round wound and 1.0 × 1010 CFU/mL (0.2 mL) maybe the best rat ulcer model. Conclusions: This study has established an evaluation system based on AHP and Delphi method, also provided the best skin ulcer models selected by this system, the models are suitable for disease research and drug development research of skin ulcer.

17.
Brain Sci ; 13(4)2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-37190547

RESUMEN

Mild cognitive impairment (MCI) in multiple-system atrophy (MSA) patients is common but remains poorly characterized, and the related factors are unclear. This retrospective study included 200 consecutive patients with a clinical diagnosis of possible or probable MSA, 102 MSA patients with MCI (MSA-MCI), and 98 MSA patients with normal cognition (MSA-NC). Cognitive profiles were compared between MSA-MCI and MSA-NC patients using the MoCA. In addition, demographic as well as major motor and nonmotor symptom differences were compared between MSA-MCI and MSA-NC patients. The median MMSE score was 26 points. Overall, MSA-MCI was observed in 51% of patients, with predominant impairment in visuospatial, executive, and attention functions compared with MSA-NC patients. MSA-MCI patients were older (p = 0.015) and had a later onset age (p = 0.024) and a higher frequency of hypertension, motor onset, and MSA with the predominant parkinsonism (MSA-P) phenotype than MSA-NC patients. The positive rate of orthostatic hypotension (OH) in MSA-MCI patients was significantly decreased and depression/anxiety was significantly increased compared with MSA-NC patients (p = 0.004). Multivariate logistic analysis showed that motor onset was independently associated with MCI in MSA patients. MSA-MCI patients had impairment in visuospatial, executive, and attention functions. More prominent memory impairment was observed in MSA-P than in MSA-C patients. Motor onset was independently associated with MCI in MSA patients. MCI was commonly presented in MSA with more prominent memory impairment in MSA-P. Future follow-up studies are warranted to identify more factors that influence cognitive impairment in MSA.

18.
Sensors (Basel) ; 23(7)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37050736

RESUMEN

High-precision and robust localization is critical for intelligent vehicle and transportation systems, while the sensor signal loss or variance could dramatically affect the localization performance. The vehicle localization problem in an environment with Global Navigation Satellite System (GNSS) signal errors is investigated in this study. The error state Kalman filtering (ESKF) and Rauch-Tung-Striebel (RTS) smoother are integrated using the data from Inertial Measurement Unit (IMU) and GNSS sensors. A segmented RTS smoothing algorithm is proposed in order to estimate the error state, which is typically close to zero and mostly linear, which allows more accurate linearization and improved state estimation accuracy. The proposed algorithm is evaluated using simulated GNSS signals with and without signal errors. The simulation results demonstrate its superior accuracy and stability for state estimation. The designed ESKF algorithm yielded an approximate 3% improvement in long straight line and turning scenarios compared to classical EKF algorithm. Additionally, the ESKF-RTS algorithm exhibited a 10% increase in the localization accuracy compared to the ESKF algorithm. In the double turning scenarios, the ESKF algorithm resulted in an improvement of about 50% in comparison to the EKF algorithm, while the ESKF-RTS algorithm improved by about 50% compared to the ESKF algorithm. These results indicated that the proposed ESKF-RTS algorithm is more robust and provides more accurate localization.

19.
ACS Omega ; 8(9): 8846-8864, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36910932

RESUMEN

In petroleum drilling, carbonate formations characterized by natural fractures can result in troublesome gas-liquid gravity displacement, which refers to the phenomenon that the drilling mud leakage and gas kick are simultaneously triggered. This work focuses on clarifying the mechanism of gas-liquid displacement in vertical fractures during the drilling of carbonate formations and investigating the characteristics of gas-liquid displacement under various conditions. First, the bottom hole pressure allowing for gas-liquid gravity displacement is analyzed, which determines the coexistence condition of leakage and kick in vertical fractures. Then, a theoretical model of gas-liquid displacement flow in a vertical fracture is established. To verify the reliability and accuracy of the model, the results of numerical simulation are compared with those of a visualization experiment. The development process and flow characteristics of gas-liquid displacement in the fracture under different conditions are numerically simulated. The effects of pressure difference, drilling mud property, and fracture geometry on the gas-liquid displacement rate are analyzed. It is found that the drilling mud leakage rate increases with the increase of fracture width, fracture height, and drilling mud density, while it decreases with the increase of pressure difference and fracture length. The gas invasion rate increases with the increase of fracture width, fracture height, and pressure difference, while it decreases with the increase of drilling mud density and fracture length. The equations for leakage rate and gas invasion rate are derived by the response surface method, and the methods for mitigating gas-liquid gravity displacement are discussed. It is expected that the present work provides a better understanding of the gas-liquid gravity displacement in carbonate formations.

20.
Front Neurorobot ; 17: 1129720, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36845066

RESUMEN

Recent adversarial attack research reveals the vulnerability of learning-based deep learning models (DNN) against well-designed perturbations. However, most existing attack methods have inherent limitations in image quality as they rely on a relatively loose noise budget, i.e., limit the perturbations by L p -norm. Resulting that the perturbations generated by these methods can be easily detected by defense mechanisms and are easily perceptible to the human visual system (HVS). To circumvent the former problem, we propose a novel framework, called DualFlow, to craft adversarial examples by disturbing the image's latent representations with spatial transform techniques. In this way, we are able to fool classifiers with human imperceptible adversarial examples and step forward in exploring the existing DNN's fragility. For imperceptibility, we introduce the flow-based model and spatial transform strategy to ensure the calculated adversarial examples are perceptually distinguishable from the original clean images. Extensive experiments on three computer vision benchmark datasets (CIFAR-10, CIFAR-100 and ImageNet) indicate that our method can yield superior attack performance in most situations. Additionally, the visualization results and quantitative performance (in terms of six different metrics) show that the proposed method can generate more imperceptible adversarial examples than the existing imperceptible attack methods.

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