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1.
Comput Methods Programs Biomed ; 224: 107031, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35878485

RESUMO

PURPOSE: The alarming increase in diseases of urinary system is a cause of concern for the populace and health experts. The traditional techniques used for the diagnosis of these diseases are inconvenient for patients, require high cost, and additional waiting time for generating the reports. The objective of this research is to utilize the proven potential of Artificial Intelligence for organ segmentation. Correct identification and segmentation of the region of interest in a medical image are important to enhance the accuracy of disease diagnosis. Also, it improves the reliability of the system by ensuring the extraction of features only from the region of interest. METHOD: A lot of research works are proposed in the literature for the segmentation of organs using MRI, CT scans, and ultrasound images. But, the segmentation of kidneys, ureters, and bladder from KUB X-ray images is found under explored. Also, there is a lack of validated datasets comprising KUB X-ray images. These challenges motivated the authors to tie up with the team of radiologists and gather the anonymous and validated dataset that can be used to automate the diagnosis of diseases of the urinary system. Further, they proposed a KUB-UNet model for semantic segmentation of the urinary system. RESULTS: The proposed KUB-UNet model reported the highest accuracy of 99.18% for segmentation of organs of urinary system. CONCLUSION: The comparative analysis of its performance with state-of-the-art models and validation of results by radiology experts prove its reliability, robustness, and supremacy. This segmentation phase may prove useful in extracting the features only from the region of interest and improve the accuracy diagnosis.


Assuntos
Inteligência Artificial , Tomografia Computadorizada por Raios X , Humanos , Processamento de Imagem Assistida por Computador/métodos , Rim/diagnóstico por imagem , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos , Raios X
2.
Rev Sci Instrum ; 91(10): 104702, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33138573

RESUMO

There is an increasing interest in synchronization of multiple spark gap switches while maintaining compact geometry, less-complex circuit, and low jitter switching performances. A study of the effect of electrical parameters on switching performances is necessary for the operation of a large number of simultaneous switches. A miniaturized trigatron switch assembly (Outer diameter: 35 mm and thickness: 5 mm) is developed and experimentally investigated for switching performance. A polyether ether ketone insulator and brass conductor electrodes are utilized due to their high insulation and solderable properties, respectively. Important switching parameters, delay time, switch time delay, jitter in delay time, discharging peak current, trigger break down time, and trigger break down voltage, are studied under four typical conditions. These four conditions are: (a) a fast trigger (FT) with normal circuit inductance (10 ns, 20 nH); (b) a fast trigger with higher circuit inductance (10 ns and 500 nH); (c) a slow trigger (ST) with normal circuit inductance (250 ns and 20 nH) and (d) a slow trigger with higher circuit inductance (250 ns and 500 nH). Subsequently, three trigatron spark gaps (4 kV, 5 kA, >100 shots, 4 nH, and 20 mΩ) are simultaneously switched within 5 ns time. Many experimental results are the first of their kind in terms of compact switch development, switching performance, and single electrical trigger based synchronization. This paper will also add a good value to presently available knowledge through systematically implementing the simultaneous switching condition for the generation of 5 kA, 50 ns current pulses. These low cost (US$40) trigatron switches can be utilized in low energy, compact pulsed power applications.

3.
Rev Sci Instrum ; 88(3): 033502, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28372365

RESUMO

This development is concerned with the compact capacitor module for a plasma focus device. Oil-free, non-standard geometry capacitors are designed and developed for high current delivery in sub-microseconds time. Metalized dielectric film based pulse capacitor becomes progressively less viable at currents above 10 kA. It is due to reliability and energy scaling difficulties, based on effects such as vaporization, high resistivity, and end connection. Bipolar electrolytic capacitors are also not preferred due to their limited life and comparatively low peak current delivery. Bi-axially oriented polypropylene (BOPP) film with extended aluminum foil is a combination to deliver moderately high power. But, electrically weak points, relative permittivity, and the edge gap margins have made its adoption difficult. A concept has been developed in lab for implementing the above combination in a less complex and costly manner. This paper concerns the development and testing process techniques for quite different hollow cylindrical, oil-free capacitors (4 µF, 10 kV, 20 nH). Shot life of 1000 has been experimentally performed on the test bed at its rated energy density level. The technological methods and engineering techniques are now available and utilized for manufacturing and testing of BOPP film based oil-free capacitors.

4.
Can J Physiol Pharmacol ; 94(1): 18-27, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26497164

RESUMO

The changes in urine flow and renal sympathetic nerve activity (RSNA) due to pulmonary lymphatic obstruction (PLO) were examined in anesthetized, artificially ventilated New Zealand white rabbits. PLO was produced by pressurizing an isolated pouch created in the right external jugular vein at the points of entry of the right lymphatic ducts. During this maneuver, urine flow increased from 8.5 ± 0.3 mL/10 min to 12 ± 0.5 mL/10 min (P < 0.0001) and RSNA increased from 24.0 ± 4 to 40.0 ± 5 µV·s (P < 0.0001). Bilateral lesioning of the paraventricular nucleus (PVN) of the hypothalamus or cervical vagotomy abolished these responses. PLO increased c-fos gene expression in the PVN. The increase in urine flow due to PLO was attenuated by muscimol and abolished by kynurenic acid microinjections into the PVN. The results show that (i) neurons in the PVN are an important relay site in the reflex arc, which is activated by PLO; and (ii) this activation is regulated by glutamatergic and partly by GABAergic input to the PVN.


Assuntos
Diurese/fisiologia , Pneumopatias/fisiopatologia , Doenças Linfáticas/fisiopatologia , Núcleo Hipotalâmico Paraventricular/fisiopatologia , Animais , Modelos Animais de Doenças , Diurese/efeitos dos fármacos , Expressão Gênica , Genes fos , Rim/inervação , Ácido Cinurênico/administração & dosagem , Pneumopatias/genética , Doenças Linfáticas/genética , Vasos Linfáticos/fisiopatologia , Microinjeções , Muscimol/administração & dosagem , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Coelhos , Reflexo/efeitos dos fármacos , Reflexo/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Vagotomia
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