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1.
PLoS One ; 19(4): e0300767, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38578733

RESUMEN

Semantic segmentation of cityscapes via deep learning is an essential and game-changing research topic that offers a more nuanced comprehension of urban landscapes. Deep learning techniques tackle urban complexity and diversity, which unlocks a broad range of applications. These include urban planning, transportation management, autonomous driving, and smart city efforts. Through rich context and insights, semantic segmentation helps decision-makers and stakeholders make educated decisions for sustainable and effective urban development. This study investigates an in-depth exploration of cityscape image segmentation using the U-Net deep learning model. The proposed U-Net architecture comprises an encoder and decoder structure. The encoder uses convolutional layers and down sampling to extract hierarchical information from input images. Each down sample step reduces spatial dimensions, and increases feature depth, aiding context acquisition. Batch normalization and dropout layers stabilize models and prevent overfitting during encoding. The decoder reconstructs higher-resolution feature maps using "UpSampling2D" layers. Through extensive experimentation and evaluation of the Cityscapes dataset, this study demonstrates the effectiveness of the U-Net model in achieving state-of-the-art results in image segmentation. The results clearly shown that, the proposed model has high accuracy, mean IOU and mean DICE compared to existing models.


Asunto(s)
Aprendizaje Profundo , Semántica , Planificación de Ciudades , Investigación Empírica , Hidrolasas , Procesamiento de Imagen Asistido por Computador
3.
Sci Rep ; 14(1): 555, 2024 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-38177235

RESUMEN

Modern energy systems are finding new applications for magnetohydrodynamic rheological bio-inspired pumping systems. The incorporation of the electrically conductive qualities of flowing liquids into the biological geometries, rheological behavior, and propulsion processes of these systems was a significant effort. Additional enhancements to transport properties are possible with the use of nanofluids. Due to their several applications in physiology and industry, including urine dynamics, chyme migration in the gastrointestinal system, and the hemodynamics of tiny blood arteries. Peristaltic processes also move spermatozoa in the human reproductive system and embryos in the uterus. The present research examines heat transport in a two-dimensional deformable channel containing magnetic viscoelastic nanofluids by considering all of these factors concurrently, which is vulnerable to peristaltic waves and hall current under ion slip and other situations. Nanofluid rheology makes use of the Sutterby fluid model, while nanoscale effects are modeled using the Buongiorno model. The current study introduces an innovative numerical computing solver utilizing a Multilayer Perceptron feed-forward back-propagation artificial neural network (ANN) with the Levenberg-Marquardt algorithm. Data were collected for testing, certifying, and training the ANN model. In order to make the dimensional PDEs dimensionless, the non-similar variables are employed and calculated by the Homotopy perturbation technique. The effects of developing parameters such as Sutterby fluid parameter, Froude number, thermophoresis, ion-slip parameter, Brownian motion, radiation, Eckert number, and Hall parameter on velocity, temperature, and concentration are demonstrated. The machine learning model chooses data, builds and trains a network, and subsequently assesses its performance using the mean square error metric. Current results declare that the improving Reynolds number tends to increase the pressure rise. Improving the Hall parameter is shown to result in a decrease in velocity. When raising a fluid's parameter, the temperature profile rises.


Asunto(s)
Ingeniería Biomédica , Redes Neurales de la Computación , Humanos , Temperatura , Calor , Movimiento (Física)
4.
Heliyon ; 9(12): e22844, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38144343

RESUMEN

The crucial aspect of the medical sector is healthcare in today's modern society. To analyze a massive quantity of medical information, a medical system is necessary to gain additional perspectives and facilitate prediction and diagnosis. This device should be intelligent enough to analyze a patient's state of health through social activities, individual health information, and behavior analysis. The Health Recommendation System (HRS) has become an essential mechanism for medical care. In this sense, efficient healthcare networks are critical for medical decision-making processes. The fundamental purpose is to maintain that sensitive information can be shared only at the right moment while guaranteeing the effectiveness of data, authenticity, security, and legal concerns. As some people use social media to recognize their medical problems, healthcare recommendation systems need to generate findings like diagnosis recommendations, medical insurance, medical passageway-based care strategies, and homeopathic remedies associated with a patient's health status. New studies aimed at the use of vast numbers of health information by integrating multidisciplinary data from various sources are addressed, which also decreases the burden and health care costs. This article presents a recommended intelligent HRS using the deep learning system of the Restricted Boltzmann Machine (RBM)-Coevolutionary Neural Network (CNN) that provides insights on how data mining techniques could be used to introduce an efficient and effective health recommendation systems engine and highlights the pharmaceutical industry's ability to translate from either a conventional scenario towards a more personalized. We developed our proposed system using TensorFlow and Python. We evaluate the suggested method's performance using distinct error quantities compared to alternative methods using the health care dataset. Furthermore, the suggested approach's accuracy, precision, recall, and F-measure were compared with the current methods.

5.
PLoS One ; 18(8): e0289823, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37566574

RESUMEN

Current methods of edge identification were constrained by issues like lighting changes, position disparity, colour changes, and gesture variability, among others. The aforementioned modifications have a significant impact, especially on scaled factors like temporal delay, gradient data, effectiveness in noise, translation, and qualifying edge outlines. It is obvious that an image's borders hold the majority of the shape data. Reducing the amount of time it takes for image identification, increase gradient knowledge of the image, improving efficiency in high noise environments, and pinpointing the precise location of an image are some potential obstacles in recognizing edges. the boundaries of an image stronger and more apparent locate those borders in the image initially, sharpening it by removing any extraneous detail with the use of the proper filters, followed by enhancing the edge-containing areas. The processes involved in recognizing edges are filtering, boosting, recognizing, and localizing. Numerous approaches have been suggested for the previously outlined identification of edges procedures. Edge detection using Fast pixel-based matching and contours mappingmethods are used to overcome the aforementioned restrictions for better picture recognition. In this article, we are introducing the Fast Pixel based matching and contours mapping algorithms to compare the edges in reference and targeted frames using mask-propagation and non-local techniques. Our system resists significant item visual fluctuation as well as copes with obstructions because we incorporate input from both the first and prior frames Improvement in performance in proposed system is discussed in result section, evidences are tabulated and sketched. Mainly detection probabilities and detection time is remarkably reinforced Effective identification of such things were widely useful in fingerprint comparison, medical diagnostics, Smart Cities, production, Cyber Physical Systems, incorporating Artificial Intelligence, and license plate recognition are conceivable applications of this suggested work.


Asunto(s)
Algoritmos , Inteligencia Artificial , Reconocimiento en Psicología
6.
Mater Today Proc ; 64: 448-451, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35502322

RESUMEN

Twitter, as is well known, is one of the most active social media platforms, with millions of tweets posted every day, in which different people express their opinions on topics such as travel, economic concerns, political decisions, and so on. As a result, it is a useful source of knowledge. We offer Sentiment Analysis using Twitter Data for the research. Initially, our technology retrieves currently accessible tweets and hashtags about various types of covid vaccinations posted on Twitter through using Twitter's API. Following that, the imported Tweets are automatically configured to generate a collection of untrained rules and random variables. To create our model, we're utilizing, Tweepy, which is a wrapper for Twitter's API. Following that, as part of the sentiment analysis of new Messages, the software produces donut graphs.

7.
J Mol Cell Cardiol ; 66: 18-26, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24445059

RESUMEN

Fat1 is an atypical cadherin that controls vascular smooth muscle cell (VSMC) proliferation and migration. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 1 (Nox1) is an important source of reactive oxygen species (ROS) in VSMCs. Angiotensin II (Ang II) induces the expression and/or activation of both Fat1 and Nox1 proteins. This study tested the hypothesis that Ang II-induced Fat1 activation and VSMC migration are mediated by Nox1-dependent ROS generation and redox signaling. Studies were performed in cultured VSMCs from Sprague­Dawley rats. Cells were treated with Ang II (1 µmol/L) for short (5 to 30 min) or long term stimulations (3 to 12 h) in the absence or presence of the antioxidant apocynin (10 µmol/L), extracellular-signal-regulated kinases 1/2 (Erk1/2) inhibitor PD98059 (1 µmol/L), or Ang II type 1 receptor (AT1R) valsartan (1 µmol/L). siRNA was used to knockdown Nox1 or Fat1. Cell migration was determined by Boyden chamber assay. Ang II increased Fat1 mRNA and protein levels and promoted Fat1 translocation to the cell membrane, responses that were inhibited by AT1R antagonist and antioxidant treatment. Downregulation of Nox1 inhibited the effects of Ang II on Fat1 protein expression. Nox1 protein induction, ROS generation, and p44/p42 MAPK phosphorylation in response to Ang II were prevented by valsartan and apocynin, and Nox1 siRNA inhibited Ang II-induced ROS generation. Knockdown of Fat1 did not affect Ang II-mediated increases in Nox1 expression or ROS. Inhibition of p44/p42 MAPK phosphorylation by PD98059 abrogated the Ang II-induced increase in Fat1 expression and membrane translocation. Knockdown of Fat1 inhibited Ang II-induced VSMC migration, which was also prevented by valsartan, apocynin, PD98059, and Nox1 siRNA. Our findings indicate that Ang II regulates Fat1 expression and activity and induces Fat1-dependent VSMC migration via activation of AT1R, ERK1/2, and Nox1-derived ROS, suggesting a role for Fat1 downstream of Ang II signaling that leads to vascular remodeling.


Asunto(s)
Angiotensina II/farmacología , Cadherinas/genética , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , NADH NADPH Oxidorreductasas/genética , Acetofenonas/farmacología , Angiotensina II/metabolismo , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Animales , Antioxidantes/farmacología , Cadherinas/agonistas , Cadherinas/antagonistas & inhibidores , Cadherinas/metabolismo , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Flavonoides/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , NADPH Oxidasa 1 , Oxidación-Reducción , Inhibidores de Proteínas Quinasas/farmacología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Tetrazoles/farmacología , Valina/análogos & derivados , Valina/farmacología , Valsartán
8.
Int J Pept Protein Res ; 36(6): 538-43, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2090646

RESUMEN

An asymmetric synthesis of [beta-(4-pyridyl-1-oxide)-L-alanine4]-angiotensin I (1a), which is a potential suicide substrate (mechanism-based inhibitor) for protein-tyrosine kinases, has been performed. Deprotonation of 6 with n-butyllithium in THF gave the anion 7, which was alkylated with 4-(chloromethyl)pyridine-1-oxide to afford intermediate 9 as a crystalline solid. Hydrolysis of 9 afforded a mixture of 11 and 12 in a ratio of 96:4 as estimated by conversion to the diastereomeric dipeptides 13 and 14 followed by HPLC analysis. The 96:4 mixture of 11 and 12 was used in the solid phase synthesis of the target angiotensin analog 1a and its diastereomer 1b, which were separated and tested for inhibitory activity against two thymocyte protein-tyrosine kinases: p40 and p56lck. Neither peptide displayed significant inhibitory activity toward p40 and both served as weak competitive inhibitors of p56lck.


Asunto(s)
Angiotensina I/análogos & derivados , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Angiotensina I/síntesis química , Angiotensina I/metabolismo
9.
J Nat Prod ; 42(6): 615-23, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-541686

RESUMEN

Dephinium cashmirianum Royle (Ranunculaceae) has yielded the new base cashmiradelphine (12), together with the known alkaloids anthranoyllycoctonine (9), lycaconitine (15), avadharidine (17), lappaconitine (4), and N-deacetyllappaconitine (7). Pyridinium chlorochromate oxidation of lycoctonine furnished the new aldehyde lycoctonal (11). The arrhythmogenic and heart rate effects of several of these diterpenoidal alkaloids have been measured on the isolated guinea atria. Lappaconitine was arrhythmogenic at 10(-4)M concentrations. But in contrast to the reference drug aconitine, lappaconitine did not increase the heart rate. In anesthetized rabbits injected with lappaconitine, N-deacetyllappaconitine, and lappaconine up to 1 mg/kg, cardiac arrhythmia was quickly observed. Even up to 5 mg/kg, the other substances were non-arrhythmogenic.


Asunto(s)
Alcaloides/aislamiento & purificación , Plantas/análisis , Alcaloides/farmacología , Animales , Arritmias Cardíacas/inducido químicamente , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Cobayas , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Masculino , Conejos
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