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Independent component analysis, a data-driven analysis method, has found significant applications in task-based as well as resting state fMRI studies. There are numbers of independent component analysis algorithms available, but only a few of them have been used frequently so far for fMRI images. With a view that algorithms that are overlooked may outperform the most opted, a comparative study is taken up in this paper to analyze their abilities for the purpose of synthesis of fMRI images. In this paper, ten independent component algorithms: Fast ICA, INFOMAX, SIMBEC, JADE, ERICA, EVD, RADICAL, ICA-EBM, ERBM, and COMBI are compared. Their separation abilities are adjudged on both, synthetic and real fMRI images. Performance to decompose synthetic fMRI images is being monitored on the basis of spatial correlation coefficients, time elapsed to extract independent components and the visual appearance of independent components. Ranking of their performances on task-based real fMRI images are based on the closeness of time courses of identified independent components with model time course and the closeness of spatial maps of components with spatial templates while their competencies for resting state fMRI data are analyzed by examining how distinctly they decompose the data into the most consistent resting state networks. Sum of mutual information between all the permutations of decomposed components of resting state fMRI data are also calculated.
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Algoritmos , Mapeo Encefálico/métodos , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Circulación Cerebrovascular/fisiología , Simulación por Computador , Humanos , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Modelos Neurológicos , Oxígeno/sangre , Fantasmas de Imagen , Descanso , Programas Informáticos , Adulto JovenRESUMEN
A series of fluorescent teraryls and quateraryls were prepared from a ketene-S,S-acetal under mild conditions. These compounds exhibited blue, sky-blue and green color emissions both in the solid state and in a solution with good quantum yields, positive solvatochromic behavior, and reversible oxidation and reduction properties. The electronic characteristics of teraryl 6a and quateraryls 9a,b were examined by time-dependent density functional theory (TDDFT) calculations. Light-emitting devices were fabricated from teraryl 6a and quateraryls 9a,b as dyes and the configuration of ITO/PEDOT:PSS (40 nm)/NPB (20 nm)/ dye (50 nm)/BCP (7 nm)/ LiF (0.7 nm)/Al (200 nm), which exhibited electroluminescence maxima of 455, 480, and 525 nm, respectively. These devices operated at a substantially low turn-on voltage (3 and 4 V) and exhibited maximum luminance efficiencies of 0.62, 0.57, and 1.9 cd/A and brightnesses of 59, 160, and 1284 cd/m(2), respectively.
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Acetales/química , Colorantes Fluorescentes/síntesis química , Sustancias Luminiscentes/síntesis química , Electrónica , Colorantes Fluorescentes/química , Cetonas/química , Luz , Sustancias Luminiscentes/química , Estructura Molecular , Teoría CuánticaRESUMEN
Speech and hearing impairments are among the most common problems in Indian societies. It can affect anyone, whether children, adults, or more. Many different treatments can help to overcome hearing problems. Different types of hearing aids and cochlear implants help amplify sounds for better hearing. The type of language known as sign language is very scientific and has its grammar and syntax. Still, due to a need for more awareness among hard-of-hearing persons, they need to be made familiar with the institutions where they can learn and equip themselves for communication. This paper describes an approach to aid speech and hard-of-hearing persons so that they are free to communicate with persons who do not have speech and hearing disabilities based on the Indian Sign Language System. To find an appropriate solution, there is a need to develop a system that can act as an interpreter for speech and hard-of-hearing persons. The interpreter system is designed with the help of the Robotic hand model and is programmed using Raspberry Pi 4. Based on the experimental results, it can be observed that the robotic hands generated different signs of the alphabet corresponding to the speech commands uttered by an individual. Several experimental trials were conducted by ten persons who do not have any hearing disabilities. The results of the five experimental trials are shown in this paper. The estimation of performance parameters and statistical analysis are also carried out to analyze better and interpret the experimental results. Based on the experimental results, the proposed robotic hand interpreter system model accurately generates gestures corresponding to different alphabets used in the Indian Sign Language system, yielding an overall accuracy of 94 percent.
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BACKGROUND: Fluoroquinolone resistance is a serious threat in the battle against the treatment of multi drug resistant tuberculosis (MDR-TB) and extensively drug resistant tuberculosis (XDR-TB). Fluoroquinolone resistant isolates from India had shown to have evolved several mutants in the quinolone resistance determining region (QRDR) of DNA gyrase A subunit (GyrA), the target of fluoroquinolone. In view of high prevalence of mutations in the 'hot spot' region, a study on combinatorial drug design was carried out to identify better analogues for the treatment of MDR-TB. The gyrA subunit 'hot spot' region of codons 90, 94 and 95 were modeled into their corresponding protein folds and used as receptors for the docking studies. Further, invitro tests were carried using the parent compounds, namely gatifloxacin and moxifloxacin and correlated with the obtained docking scores. RESULTS: Molecular docking and in vitro studies correlated well in demonstrating the enhanced activity of moxifloxacin, when compared to gatifloxacin, on ofloxacin sensitive and resistant strains comprising of clinical isolates of MDR-TB. The evolved lead structures targeting against mutant QRDR receptors were guanosine and cholesteryl esters of gatifloxacin and moxifloxacin. They showed consistently high binding affinity values of -10.3 and -10.1 kcal/mol respectively with the target receptors. Of these, the guanosine ester showed highest binding affinity score and its log P value lied within the Lipinski's range indicating that it could have better absorptivity when it is orally administered thereby having an enhanced activity against MTB. CONCLUSIONS: The docking results showed that the addition of the cholesteryl and guanosine esters to the 'DNA gyrase binding' region of gatifloxacin and moxifloxacin enhanced the binding affinity of these parent molecules with the mutant DNA gyrase receptors. Viewing the positive correlation for the docking and in vitro results with the parent compounds, these lead structures could be further evaluated for their in vitro and in vivo activity against MDR-TB.
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Girasa de ADN/metabolismo , Fluoroquinolonas/metabolismo , Fluoroquinolonas/farmacología , Modelos Moleculares , Mutación , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/genética , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacología , Compuestos Aza/química , Compuestos Aza/metabolismo , Compuestos Aza/farmacología , Secuencia de Bases , Sitios de Unión , Cristalografía por Rayos X , Girasa de ADN/química , Girasa de ADN/genética , Diseño de Fármacos , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Múltiples Medicamentos/genética , Fluoroquinolonas/química , Gatifloxacina , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Moxifloxacino , Mycobacterium tuberculosis/efectos de los fármacos , Conformación Proteica , Quinolinas/química , Quinolinas/metabolismo , Quinolinas/farmacologíaRESUMEN
A new series of thermally stable blue light-emitting nonplanar pyrenylarenes having an amine donor and a nitrile acceptor group was prepared from a ketene-S,S-acetal under conventional heating and/or microwave irradiation. The photophysical, electrochemical, and optical behavior of donor-acceptor pyrenylarenes are demonstrated. The performance of blue light-emitting pyrenylarenes was investigated by fabricating a multilayer device with the device configuration of ITO/PEDOT:PSS (40 nm)/NPB (30 nm)/pyrenylarene (55 nm)/BCP (8 nm)/LiF (0.6 nm)/Al (200 nm), which exhibited low turn-on voltage (5 V) with luminance efficiency of 0.8 Cd/A with nonaggregation behavior in both solution and solid state.
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Hidrocarburos/química , LuzRESUMEN
Locating cognitive task states by measuring changes in electrocortical activity due to various attentional and sensory-motor changes, has been in research interest since last few decades. In this paper, different cognitive states while performing various attentional and visuo-motor coordination tasks, are classified using electroencephalogram (EEG) signal. A non-linear time-series method, multifractal detrended fluctuation analysis (MFDFA) , is applied on respective EEG signal for features. Using MFDFA based features a multinomial classification is achieved. Nine channel EEG signal was recorded for 38 young volunteers (age: 25 ± 5 years, 30 male and 8 female), during six consecutive tasks. First three tasks are related to increasing levels of selective focus vision; next three are reflex and response based computer tasks. Total of 90 features (ten features from each of nine channel) were extracted from Hurst and singularity exponents of MFDFA on EEG signals. After feature selection, a multinomial classifier of six classes using two methods: support vector machine (SVM) and decision tree classifier (DTC). An accuracy of 96.84% using SVM and 92.49% using DTC was achieved.
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A novel series of thermally stable yellow light emitting fluoranthenes with an amine donor and a nitrile acceptor was prepared from a ketene-S,S-acetal under mild conditions without using an organometal catalyst. The organic light emitting device of yellow fluoranthene 10b exhibited substantially low turn-on voltage (2.6 V) and maximum brightness of 470 Cd/m(2) with luminance efficiency of 2.0 Cd/A without using any dopant.
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Fluorenos/química , Fluorescencia , Acetales/química , Aminas/química , Color , Fluorenos/síntesis química , Nitrilos/químicaRESUMEN
Astaxanthin (AXN) is known to have health benefits by epidemiological studies. Therefore, it is of interest to assess the effect of AXN (derived from indigenous unicellular green alga Haematococcus lacustris) to modulate cell cycle arrest, lysosomal acidification and eventually apoptosis using in vitro in A549 lung cancer cells. Natural extracts of astaxanthin were obtained by standardized methods as reported earlier and characterized by standard HPLC and MS. Treatment of A549 cells with AXN (purified fraction) showed significant reduction in cell viability (about 50%) as compared to crude extract at 50µM concentration. Thus, we show the anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris for further consideration. Together, our results demonstrated the anticancer potential of AXN from Haematococcus lacustris, which is found to be mediated via its ability to induce cell cycle arrest, lysosomal acidification and apoptotic induction.
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A novel series of thermally stable blue light emitting quateraryls with a piperidine donor and a nitrile acceptor was prepared from a ketene- S, S-acetal under mild conditions without using an organometal catalyst. The performance of a blue quateraryl 6e was investigated by fabricating a multilayer OLED with a configuration of ITO/PEDOT:PSS (40 nm)/quateraryl (60 nm)/BCP (6 nm)/Alq(3) (20 nm)/LiF (0.5 nm)/Al (200 nm), which exhibited blue emission with a low turn on voltage of 4 V at a brightness of 0.22 cd/m(2).
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Luminiscencia , Piperidinas/química , Hidrocarburos Policíclicos Aromáticos/síntesis química , Acetales/química , Catálisis , Color , Cristalografía por Rayos X , Gases , Conformación Molecular , Estructura MolecularRESUMEN
This article discusses an adaptive filtering technique for reducing speckle using second order statistics of the speckle pattern in ultrasound medical images. Several region-based adaptive filter techniques have been developed for speckle noise suppression, but there are no specific criteria for selecting the region growing size in the post processing of the filter. The size appropriate for one local region may not be appropriate for other regions. Selection of the correct region size involves a trade-off between speckle reduction and edge preservation. Generally, a large region size is used to smooth speckle and a small size to preserve the edges into an image. In this paper, a smoothing procedure combines the first order statistics of speckle for the homogeneity test and second order statistics for selection of filters and desired region growth. Grey level co-occurrence matrix (GLCM) is calculated for every region during the region contraction and region growing for second order statistics. Further, these GLCM features determine the appropriate filter for the region smoothing. The performance of this approach is compared with the aggressive region-growing filter (ARGF) using edge preservation and speckle reduction tests. The processed image results show that the proposed method effectively reduces speckle noise and preserves edge details.
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Algoritmos , Ultrasonografía/métodos , Animales , Procesamiento de Imagen Asistido por Computador , Hígado/diagnóstico por imagen , Procesamiento de Señales Asistido por Computador , Bazo/diagnóstico por imagenRESUMEN
In the present paper analysis of phonocardiogram (PCG) records are presented. The analysis has been carried out in both time and frequency domains with the aim of detecting certain correlations between the time and frequency domain representations of PCG. The analysis is limited to first and second heart sounds (S1 and S2) only. In the time domain analysis the moving window averaging technique is used to determine the occurrence of S1 and S2, which helps in determination of cardiac interval and absolute and relative time duration of individual S1 and S2, as well as absolute and relative duration between them. In the frequency domain, fast Fourier transform (FFT) of the complete PCG record, and short time Fourier transform (STFT) and wavelet transform of individual heart sounds have been carried out. The frequency domain analysis gives an idea about the dominant frequency components in individual records and frequency spectrum of individual heart sounds. A comparative observation on both the analyses gives some correlation between time domain and frequency domain representations of PCG.
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Algoritmos , Diagnóstico por Computador/métodos , Soplos Cardíacos/diagnóstico , Fonocardiografía/métodos , Espectrografía del Sonido/métodos , Análisis de Fourier , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Clinically, the severity of valvular regurgitation is assessed by manual tracing of the regurgitant jet in the respective chambers. This work presents a computer-aided diagnostic (CAD) system for the assessment of the severity of mitral regurgitation (MR) based on image processing that does not require the intervention of the radiologist or clinician. Eight different texture feature sets from the regurgitant area (selected through an arbitrary criterion) have been used in the present approach. First order statistics have been used initially, however, observing their limitations, the other texture features such as spatial gray level difference matrix, gray level difference statistics, neighborhood gray tone difference matrix, statistical feature matrix, Laws' textures energy measure, fractal dimension texture analysis and Fourier power spectrum have additionally been used. For the classification task a supervised classifier i.e., support vector machine has been used in the present approach. The classification accuracy has been improved significantly by using these texture features in combination, in comparison to when fed individually as input to the classifier. The classification accuracy of 95.65±1.09, 95.65±1.09 and 95.36±1.13 has been obtained in apical two chamber, apical four chamber and parasternal long axis views, respectively. Therefore, the results of this paper indicate that the proposed CAD system may effectively assist the radiologists in establishing (confirming) the MR stages, namely, mild, moderate and severe.
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Diagnóstico por Computador/métodos , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Insuficiencia de la Válvula Mitral , Índice de Severidad de la Enfermedad , Ultrasonografía , Femenino , Humanos , Masculino , Insuficiencia de la Válvula Mitral/diagnóstico por imagenRESUMEN
Several investigators have suggested that the conventional multicompartmental exponential analysis of in vivo glucose metabolism is arbitrary and possibly not the most accurate description of glucose kinetics, especially in the large animal. In support of that hypothesis, we found that in a systematic comparison of 3 methods, blood-specific radioactivity data in single-injection studies of glucose metabolism in lactating cows was better described graphically, or by a hybrid polynomial-biexponential curve fit, than by an exclusively exponential curve fit. We hypothesized that this finding was attributable to partial failure of linearity and steady-state assumptions that underlie the exponential model. Second, using both an irreversible tracer (3H-labeled glucose) and reversible tracer (14C-labeled glucose), we found that glucose carbon recycling had no effect during the first 2 hours, but became significant in lactating cows 7 hours after injection. Finally, we determined that approximately 52 to 55% of the glucose replacement rate was being used to generate lactose.
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Bovinos/metabolismo , Glucosa/metabolismo , Lactancia/metabolismo , Lactosa/metabolismo , Animales , Glucemia/metabolismo , FemeninoRESUMEN
678 under five children were surveyed in village Shahbad Mohammadpur, Delhi. Two weeks morbidity was also recorded. 47.9 per cent children had one or more risk factors studied. Significantly more female children (54.1 per cent) were at risk than male children (43.3 per cent). 433 risk factors were observed in 325 at risk children. Majority of them had one or two risk factors. Birth interval less than two years and malnutrition were most frequent risk factors. At risk children suffered significantly more than not at risk (21.2 per cent vs 14.4 per cent). The results confirmed the validity of the risk factors considered for the study.
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Indicadores de Salud , Morbilidad , Población Rural , Intervalo entre Nacimientos , Preescolar , Femenino , Humanos , India/epidemiología , Lactante , Recién Nacido , Masculino , Trastornos Nutricionales/complicaciones , Prevalencia , Factores de RiesgoRESUMEN
BACKGROUND: Computer-based analysis of digitalized histological images has been gaining increasing attention, due to their extensive use in research and routine practice. The article aims to contribute towards the description and retrieval of histological images by employing a structural method using graphs. Due to their expressive ability, graphs are considered as a powerful and versatile representation formalism and have obtained a growing consideration especially by the image processing and computer vision community. METHODS: The article describes a novel method for determining similarity between histological images through graph-theoretic description and matching, for the purpose of content-based retrieval. A higher order (region-based) graph-based representation of breast biopsy images has been attained and a tree-search based inexact graph matching technique has been employed that facilitates the automatic retrieval of images structurally similar to a given image from large databases. RESULTS: The results obtained and evaluation performed demonstrate the effectiveness and superiority of graph-based image retrieval over a common histogram-based technique. The employed graph matching complexity has been reduced compared to the state-of-the-art optimal inexact matching methods by applying a pre-requisite criterion for matching of nodes and a sophisticated design of the estimation function, especially the prognosis function. CONCLUSION: The proposed method is suitable for the retrieval of similar histological images, as suggested by the experimental and evaluation results obtained in the study. It is intended for the use in Content Based Image Retrieval (CBIR)-requiring applications in the areas of medical diagnostics and research, and can also be generalized for retrieval of different types of complex images. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1224798882787923.
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Mama/patología , Gráficos por Computador , Diagnóstico por Computador/métodos , Interpretación de Imagen Asistida por Computador , Almacenamiento y Recuperación de la Información , Reconocimiento de Normas Patrones Automatizadas , Algoritmos , Automatización , Biopsia , Femenino , Humanos , Modelos Teóricos , Valor Predictivo de las Pruebas , Coloración y EtiquetadoAsunto(s)
Ovinos/fisiología , Agua , Animales , Diuresis , Ingestión de Líquidos , Técnica de Dilución de Radioisótopos , Sed , TritioRESUMEN
Currently, radiologists indicate the femur endpoints with an interactive marker device; however, these measurements are subjective and have proved to be inconsistent. The main objective of this work is to obtain a time-efficient morphology-based algorithm to recognize femur contour in fetal ultrasound images, refine its shape for automatic length measurement, and thus, attaining accuracy and reproducibility of measurement. To achieve these objectives a cross-sectional study with subjects belonging to different family units of different communities was carried out. The images obtained from the subjects were initially processed using morphological operators to remove the background from the image. Thereafter, to refine the shape of the femur, the images were metamorphosed, using the morphological operators, till a single pixel - wide skeleton of the femur was available in the most time-effective manner. The skeleton-end-points are assumed to be the femur-end-points, and the femur length is calculated as the distance between the end-points to estimate gestational age. The mean execution time of the proposed algorithm was around 4 seconds. Measurements, performed using the automation algorithm, were found to be closely correlated to those obtained manually. The proposed algorithm was found to be time-efficient, and the results obtained were comparable to those derived through the existing methods for estimation of gestational age.
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Biometría/métodos , Fémur/diagnóstico por imagen , Edad Gestacional , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Técnica de Sustracción , Ultrasonografía Prenatal/métodos , Fémur/embriología , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
This paper investigates the use of morphology-based nonlinear filters, and performs deterministic and statistical analysis of the linear combinations of the filters for the image quality enhancement of B-mode ultrasound images. The fact that the structuring element shape greatly influences the output of the filter, is one of the most important features of mathematical morphology. The present reported work comparatively evaluates the structuring elements for morphological liver image enhancement and verifies the hypothesis that the speckles visible in US images are short, slightly 'banana-shaped' white lines. Initially, five different liver images were morphologically filtered using 10 different structuring elements and then the filtered images were assessed quantitatively. Image quality parameters such as peak signal-to-noise ratio, mean square error and correlation coefficient have been used to evaluate the performance of the morphological filters with different structuring elements. To endorse the observation of the quantitative analysis, the filtered images were then evaluated qualitatively, based on the image features looked into by the medical fraternity. The evaluation parameters have been taken on the basis of the suggestions made by a group of radiologists. The results of the processed images were then evaluated by a different group of radiologists. A multi-point rank order method has been used to identify small differences or trends in observation. The subjective analysis by radiologists indicates that morphological filter using line shaped structuring element with length 2 performs better than the other structuring elements. These observations were found to be in line with the observations of quantitative analysis.
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Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Ultrasonografía , Algoritmos , Humanos , Hígado/diagnóstico por imagen , Hepatopatías/diagnóstico por imagenRESUMEN
The "green emission defect" (GED) produced by fluorenones has significantly retarded the commercial scope of fluorene-based B-OLEDs. In this paper, for the first time, it is demonstrated that the "green light" emitting fluorenones 7 can be converted to "blue light" emitting fluorenones 10 by appropriate positioning of donor-acceptor and chromophoric groups onto the fluorene/fluorenone backbone. Additionally, we report an elegant highly rapid synthetic route for donor-acceptor fluorenes and fluorenones at room temperature with excellent yields.
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Fluorenos/síntesis química , Fotoquímica , Fluorenos/química , Luminiscencia , Estructura MolecularRESUMEN
Glucose biokinetics were assessed simultaneously in the pregnant ewe and its fetus by a primed constant infusion of 2-3H glucose and U-14C glucose. Late in gestation fetal glucose turnover was 27.3 +/- 3.7 mg/min; expressed in terms of fetal weight this is 6 to 10 mg/kg/min. In the fed state the results indicated that all of the fetal glucose turnover was derived from the mother via placental transfer and there was no evidence that the fetus was capable of glucose production. Maternal glucose turnover was 145.6 +/- 9.3 mg/min (2.8 mg/kg/min). There was a significant amount of glucose (16.3 +/- 2.3 mg/min) transferred from the fetus to the mother. This feto-maternal transfer of glucose accounted for 11% of the maternal glucose turnover and approximately 50% of the total glucose coming to the fetus from the mother. This study provides the first in vivo simultaneous quantification of the bidirectional glucose transfer across the placenta.