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1.
J Vis ; 21(1): 13, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33502438

RESUMEN

The features of perceptual surround suppression vary with eccentricity, such that the suppression strength is increased for horizontally oriented stimuli relative to other orientations near the fovea, but is strongest for radially oriented stimuli more peripherally. Perceptual suppression also varies with age, which has been well-studied for central fixation. However, only limited data are available regarding perceptual suppression in older adults for nonfoveal vision, and none of those studies have taken orientation biases of contrast sensitivity into account. Here, we explored the effects of older age on the eccentricity dependency of orientation biases of perceptual suppression. We found increased perceptual suppression in older adults at both 6° and 15° eccentricities relative to younger adults. A main effect of the horizontal orientation bias was found at 6° and a main effect of the radial orientation bias was found at 15° in both groups. In summary, perceptual surround suppression of contrast is stronger for older adults compared with younger adults at 6° and 15° eccentricities, but retinotopic orientation anisotropies are maintained with age. This study provides new insight into parafoveal visual perception in older adults, which may be particularly important to understand the visual experience of those who depend on nonfoveal vision owing to common age-related eye diseases.


Asunto(s)
Envejecimiento/fisiología , Orientación Espacial/fisiología , Adulto , Anciano , Anisotropía , Sensibilidad de Contraste/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Percepción Visual , Adulto Joven
2.
J Vis ; 18(7): 5, 2018 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-30029269

RESUMEN

Both neurophysiological and psychophysical data provide evidence for orientation biases in nonfoveal vision-specifically, a tendency for a Cartesian horizontal and vertical bias close to fixation, changing to a radial bias with increasing retinal eccentricity. We explore whether the strength of surround suppression of contrast detection also depends on retinotopic location and relative surround configuration (horizontal, vertical, radial, tangential) in parafoveal vision. Three visual-field locations were tested (0°, 225°, and 270°, angle increasing anticlockwise from 0° horizontal axis) at viewing eccentricities of 6° and 15°. Contrast-detection threshold was estimated with and without a surrounding annulus. At 6° eccentricity, horizontally oriented parallel center-surround (C-S) configurations resulted in greater surround suppression compared to vertically oriented parallel center-surround configurations (p = 0.001). At 15° eccentricity, radially oriented parallel center-surround stimuli conferred greater suppression than tangentially oriented stimuli (p = 0.027). Parallel surrounds resulted in greater suppression than orthogonal surrounds at both eccentricities (p < 0.05). At 6° the horizontal center was more susceptible to suppression than a vertical center (p < 0.001) for both parallel and orthogonal surrounds, while at 15° a radial center was more susceptible to suppression (relative to a tangential center), but only if the surround was parallel (p = 0.005). Our data show that orientation anisotropy of surround suppression alters with eccentricity, reflecting a link between suppression strength and visual-field retinotopy.


Asunto(s)
Sensibilidad de Contraste/fisiología , Orientación/fisiología , Percepción Visual/fisiología , Adulto , Anisotropía , Femenino , Humanos , Masculino , Orientación Espacial , Psicofísica , Retina/fisiología , Umbral Sensorial/fisiología , Campos Visuales/fisiología , Adulto Joven
3.
Cureus ; 16(2): e54031, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38481883

RESUMEN

Background The value and use of medicinal plants, including the widespread cultivation of Rosmarinus officinalis, have increased rapidly. R. officinalis, a medicinal plant native to the Mediterranean, has received attention for its potential therapeutic benefits. This study evaluates R. officinalis anticancer activity using human epithelial carcinoma (KB) cell lines derived from nasopharyngeal epidermoid carcinoma. The KB cell line is known for its increased sensitivity to specific chemotherapeutic agents (CA), making it a useful model in cancer research. The impact of R. officinalis is assessed using comprehensive analyses of cell viability and gene expression. Aim This study aims to evaluate the anti-cancer effects of R. officinalis on KB cell lines. Materials and methods The R. officinalis leaf extract was separated and used to treat KB cell lines. The cell viability of treated KB cells was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Real-time polymerase chain reaction (RT-PCR) was used to analyze the expressions of matrix metalloproteinase (MMP-9) and tumor-inducing metalloproteins (TIMP-1) messenger ribonucleic acid (mRNA) genes. The statistical analysis was performed. Results This study analyzes the anticancer properties of R. officinalis on KB cell lines. The results show that increasing the concentration of rosemary extract reduces cell viability in malignant cells. Furthermore, the R. officinalis effect on the apoptotic signaling system is demonstrated by a decrease in MMP-9 and TIMP-1 mRNA expressions, as observed by RT-PCR analysis. Conclusion Patients looking for natural anticancer treatments may benefit from biogenically prepared anticancer drugs. The current research focuses on R. officinalis as a potential alternative to chemically synthesized anticancer drugs.

4.
Cureus ; 16(7): e63925, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39105038

RESUMEN

Background In recent years, significant advancements have been made in various scientific sectors, particularly in healthcare and pharmaceutical research. This progress has been driven by the development of enhanced sensing materials and methodologies. Electrochemical sensing has become an important tool in detecting and analyzing drug molecules due to its high sensitivity, specificity, and rapid response times. Among various drugs, paracetamol, also known as acetaminophen, is widely used for its analgesic and antipyretic properties. Accurate detection of paracetamol is crucial due to its widespread use and potential for overdose, which can lead to severe liver damage. Copper molybdate (CuMoO4) is a transition metal oxide that has garnered attention for its excellent electrical conductivity and electrochemical stability. These properties make it a promising candidate for use in electrochemical sensors. The ability of CuMoO4 to act as a sensor material is enhanced by its unique structural and morphological characteristics, which can be tailored during synthesis. Aim This study aimed to synthesize CuMoO4 and investigate its electrochemical sensing capability for the detection of drug molecules, specifically paracetamol. Materials and method CuMoO4 was synthesized using a precipitation method that did not involve any surfactants. This approach was chosen to simplify the synthesis process and avoid potential contamination from surfactants. The morphology of the synthesized CuMoO4 nanoparticles was investigated using a field emission scanning electron microscope (FE-SEM). Energy-dispersive X-ray spectroscopy (EDX) confirmed the purity of the CuMoO4 nanomaterial. Structural analysis was performed using X-ray diffraction (XRD). To evaluate the electrochemical sensing capability of CuMoO4 for paracetamol, Differential pulse voltammetry (DPV) was employed. DPV is a sensitive electrochemical technique that can detect changes in current response corresponding to the presence of analytes. Results The synthesized CuMoO4 exhibited a rock-like structure, as revealed by FE-SEM imaging. This morphology is advantageous for electrochemical applications due to the increased surface area available for interaction with analytes. EDX confirmed the purity of the CuMoO4 nanomaterial, showing no significant impurities. XRD analysis indicated that the CuMoO4 nanoparticles were crystalline in nature, which is beneficial for consistent and reproducible electrochemical behavior. The DPV analysis demonstrated that the CuMoO4 sensor exhibited a linear increase in current response with increasing concentrations of paracetamol. This linear relationship indicates that CuMoO4 is capable of detecting paracetamol effectively, with a strong and quantifiable signal response. Conclusion The CuMoO4 nanomaterial was successfully synthesized using a simple precipitation method and was characterized by its rock-like morphology and crystalline structure. Electrochemical testing using DPV showed that CuMoO4 has excellent sensing capabilities for detecting paracetamol, with a clear and linear current response. These findings suggest that CuMoO4 is a promising electrochemical sensing material for drug detection, potentially offering a reliable and efficient method for monitoring paracetamol and possibly other pharmaceuticals in various settings.

5.
Sci Rep ; 13(1): 17822, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857665

RESUMEN

Human activity recognition (HAR) is one of the key applications of health monitoring that requires continuous use of wearable devices to track daily activities. The most efficient supervised machine learning (ML)-based approaches for predicting human activity are based on a continuous stream of sensor data. Sensor data analysis for human activity recognition using conventional algorithms and deep learning (DL) models shows promising results, but evaluating their ambiguity in decision-making is still challenging. In order to solve these issues, the paper proposes a novel Wasserstein gradient flow legonet WGF-LN-based human activity recognition system. At first, the input data is pre-processed. From the pre-processed data, the features are extracted using Haar Wavelet mother- Symlet wavelet coefficient scattering feature extraction (HS-WSFE). After that, the interest features are selected from the extracted features using (Binomial Distribution integrated-Golden Eagle Optimization) BD-GEO. The important features are then post-processed using the scatter plot matrix method. Obtained post-processing features are finally given into the WGF-LN for classifying human activities. From these experiments, the results can be obtained and showed the efficacy of the proposed model.


Asunto(s)
Dispositivos Electrónicos Vestibles , Humanos , Actividades Humanas , Algoritmos , Aprendizaje Automático Supervisado , Inteligencia
6.
Indian J Ophthalmol ; 71(7): 2733-2738, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37417113

RESUMEN

Purpose: To find out the mean rate of progression (MROP) of visual fields (VF) in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT) using FORUM® Glaucoma Workplace. Methods: Two hundred and one eyes of 105 patients were included in this prospective cohort study. Patients with POAG and OHT were recruited, and VF analysis with 24-2 and or 10-2 was done using SITA standard strategy in Zeiss Humphrey Visual Field Analyzer (HFA). All the previous VFs were identified from FORUM software, and the baseline indices were recorded from the first reliable VF analysis. The present VF analysis was compared to the previous one using FORUM software, and the rate of progression (ROP) in VF was obtained by Guided Progression Analysis. Results: MROP of VF in the POAG group was - 0.085 dB/year, ranging from -2.8 to 2.8 dB/year with a standard deviation (SD) of 0.69. In the OHT group, the MROP of VF was -0.003 dB/year, ranging from - 0.8 to 0.5 dB/year with an SD of 0.27. The MROP of VF in medically treated eyes with POAG was -0.14 dB/year with an SD of 0.61 and in surgically treated eyes was -0.02 dB/year with an SD of 0.78. The overall baseline mean VF index (VFI) was 83.19% and the final mean VFI was 79.80%. There was a statistically significant decrease in the mean VFI value from baseline to the final visit (P-value 0.0005). Conclusion: The mean ROP of VF in the POAG group was -0.085 dB/year and in the OHT group was - 0.003 dB/year.


Asunto(s)
Glaucoma de Ángulo Abierto , Glaucoma , Hipertensión Ocular , Humanos , Campos Visuales , Glaucoma de Ángulo Abierto/diagnóstico , Glaucoma de Ángulo Abierto/cirugía , Presión Intraocular , Estudios Prospectivos , Centros de Atención Terciaria , Trastornos de la Visión , Hipertensión Ocular/diagnóstico , Hipertensión Ocular/epidemiología , Pruebas del Campo Visual , Lugar de Trabajo , Progresión de la Enfermedad
7.
Invest Ophthalmol Vis Sci ; 58(2): 860-867, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28159973

RESUMEN

Purpose: The purpose of this study was to study how, in midperipheral vision, aging affects visual processes that interfere with target detection (crowding and surround suppression) and to determine whether the performance on such tasks are related to visuospatial attention as measured by visual search. Methods: We investigated the effect of aging on crowding and suppression in detection of a target in peripheral vision, using different types of flanking stimuli. Both thresholds were also obtained while varying the position of the flanker (placed inside or outside of target, relative to fixation). Crowding thresholds were also estimated with spatial uncertainty (jitter). Additionally, we included a visual search task comprising Gabor stimuli to investigate whether performance is related to top-down attention. Twenty young adults (age, 18-32 years; mean age, 26.1 years; 10 males) and 19 older adults (age, 60-74 years; mean age, 70.3 years; 10 males) participated in the study. Results: Older adults showed more surround suppression than the young (F[1,37] = 4.21; P < 0.05), but crowding was unaffected by age. In the younger group, the position of the flanker influenced the strength of crowding, but not the strength of suppression (F[1,39] = 4.11; P < 0.05). Crowding was not affected by spatial jitter of the stimuli. Neither crowding nor surround suppression was predicted by attentional efficiency measured in the visual search task. There was also no significant correlation between crowding and surround suppression. Conclusions: We show that aging does not affect visual crowding but does increase surround suppression of contrast, suggesting that crowding and surround suppression may be distinct visual phenomena. Furthermore, strengths of crowding and surround suppression did not correlate with each other nor could they be predicted by efficiency of visual search.


Asunto(s)
Envejecimiento/fisiología , Atención/fisiología , Sensibilidad de Contraste/fisiología , Reconocimiento Visual de Modelos/fisiología , Enmascaramiento Perceptual/fisiología , Percepción Espacial/fisiología , Adolescente , Adulto , Anciano , Discriminación en Psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Umbral Sensorial/fisiología , Campos Visuales/fisiología , Adulto Joven
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