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In this study, three commercially available low-density polyethylene (LDPE) polymers produced via a tubular reactor process, with varying melt flow rates at 190°C/2.16 kg (4.0, 1.9, and 0.75 g/10 min), have been selected and subjected to high temperature-size exclusion chromatography (SEC) analysis coupled with an infrared-5 (IR-5), viscometer (VISCO), and multiangle laser light-scattering detectors. The molecular weight (MW), MW distribution, short-chain branching (SCB), and long-chain branching parameters were investigated. It was found that MW obtained by the universal technique (â¼1.57-1.7 times) and multiangle laser light-scattering detection technique is (â¼1.43-1.55 times) higher than that of the conventional calibration technique, which could be attributed to structural complexity associated with LDPEs which is not clearly understood by conventional SEC mode alone. The bulk SCB per 1000 total carbon atoms estimated by IR-5 detection was found to range from 16.50 to 17.80. On the other hand, long chain branching frequency per 1000 total carbon atoms obtained by online VISCO and multiangle laser light-scattering detection ranged from 0.46 to 0.54 and 0.65 to 0.94, respectively. Further, the significance of long chain branching parameters on the polymer processing behavior was studied in correlation with rheological property (Die swell ratio).
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AIM: To examine computed tomography (CT) radiomic feature stability on various texture patterns during pre-processing utilizing the Credence Cartridge Radiomics (CCR) phantom textures. MATERIALS AND METHODS: Imaging Biomarker Explorer (IBEX) expansion for the abbreviation IBEX extracted 51 radiomic features of 4 categories from 11 textures image regions of interest (ROI) of the phantom. 19 software pre-processing algorithms processed each CCR phantom ROI. All ROI texture processed image features were retrieved. Pre-processed CT image radiomic features were compared to non-processed features to measure its textural influence. Wilcoxon T-tests measured the pre-processing relevance of CT radiomic features on various textures. Hierarchical cluster analysis (HCA) was performed to cluster processer potency and texture impression likeness. RESULTS: The pre-processing filter, CT texture Cartridge, and feature category affect the CCR phantom CT image's radiomic properties. Pre-processing is statistically unaltered by Gray Level Run Length Matrix (GLRLM ) expansion for the abbreviation GLRLM and Neighborhood Intensity Difference matrix (NID) expansion for the abbreviation NID feature categories. The 30%, 40%, and 50% honeycomb are regular directional textures and smooth 3D-printed plaster resin, most of the image pre-processing feature alterations exhibited significant p-values in the histogram feature category. The Laplacian Filter, Log Filter, Resample, and Bit Depth Rescale Range pre-processing algorithms hugely influenced histogram and Gray Level Co-occurrence Matrix (GLCM) image features. CONCLUSION: We found that homogenous intensity phantom inserts, CT radiomic feature, are less sensitive to feature swaps during pre-processing than normal directed honeycomb and regular projected smooth 3D-printed plaster resin CT image textures. Because they lose fewer information during image enhancement, This feature concentration empowerment of the images also enhances texture pattern recognition.
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Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Rayos X , Humanos , Tomografía Computarizada por Rayos X/métodos , Tomógrafos Computarizados por Rayos X , Fantasmas de Imagen , Procesamiento de Imagen Asistido por Computador/métodos , AlgoritmosRESUMEN
AIM: To verify if computed tomography (CT) radiomics were reproducible by cone beam CT (CBCT) radiomics by using Catphan® 504. MATERIALS AND METHODS: Catphan® 504 was imaged using the default IGRT OBI CBCT imaging protocols and CT scanner. Seven known density image regions of the phantom were segmented and image feature was extracted by Imaging Biomarker Explorer (IBEX) software. The 49 selected features from four feature categories were analyzed by considering each region of interest (ROI) segment as individual image set. Correlation was studies using interclass correlation coefficient (ICC) and Pearson's correlation coefficient. RESULTS: The ICC of the three feature categories, namely intensity, GLCM, and GLRLM was significant (p-value<0.05) in comparison with CT, while the ICC of the fourth feature category, NID, was no significant. The average absolute Pearson's correlation coefficient from the features of the images was as follows: CT: r=0.679±0.257, CBCThead: r=0.707±0.231, CBCTthorax: r=0.643±0.260, and CBCTpelvis: r=0.594±0.276. CONCLUSION: It seems that the various densities of Catphan® 504 ROI image segments of the CT radiomics are reproducible with CBCT radiomics and CBCT radiomics can be used as an independent modality.
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Algoritmos , Tomografía Computarizada de Haz Cónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Tomógrafos Computarizados por Rayos X/estadística & datos numéricos , Humanos , Dosificación Radioterapéutica , Radioterapia de Intensidad ModuladaRESUMEN
INTRODUCTION: Endometrial cancer (EC) is a leading cause of female cancer in developed countries. The total abdominal hysterectomy and bilateral salpingo-oophorectomy with pelvic lymph node dissection is the primary management of endometrial cancer. Afterwards vaginal brachytherapy can be preferred either alone or combined with external beam radiotherapy to avoid the vault recurrence. This study was to assess the in-house multichannel applicator for HDR vaginal brachytherapy and dosimetric compression with the single channel applicator through DVHs. The main objective of this study was to design and development of an in-house multichannel applicator for HDR vaginal brachytherapy and dosimetric compression with the single channel applicator through DVHs. MATERIALS AND METHODS: The multichannel applicator is a solid cylinder with 3 cm diameter, 13 cm length. It has a central channel surrounded by eight channels with a periphery arrangement in a single circle. We randomly selected eleven patients with endometrial carcinoma and 7Gy/per fraction of HDR dose was prescribed to CTV. Retrospectively, two 3D inverse treatment plans were created for each patient, with single channel loading and multichannel loading and the dose distribution of both plans could be compared. CTV coverage, rectum and bladder doses were compared. RESULTS: The DVH analysis showed statistically significant difference between single and multichannel plan, that is for D95 of CTV (p=0.008), D100 of CTV (p=0.004) and 2cc of CTV (p=0.003). The p value for 1cc, 2cc and V70 are 0.003, 0.003 and 0.003 for rectum. On the other hand, bladder DVHs showed large difference between single and multichannel plan yet it is not statistically significant, and the p values for 1cc, 2cc and V 80 are 0.012, 0.009 and 0.225. CONCLUSION: The authors conclude that in house multichannel applicator with 3D inverse treatment planning techniques improves the dosimetric advantage over single channel applicators.
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Braquiterapia/instrumentación , Neoplasias Endometriales/radioterapia , Diseño de Equipo/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias Vaginales/radioterapia , Adulto , Anciano , Braquiterapia/métodos , Femenino , Estudios de Seguimiento , Humanos , Histerectomía/métodos , Persona de Mediana Edad , Órganos en Riesgo/efectos de la radiación , Pronóstico , Dosificación RadioterapéuticaRESUMEN
Facial onset sensory motor neuronopathy (FOSMN) is a recently identified condition characterized initially by trigeminal sensory involvement followed by sensory propagation and motor neuronopathy. Few cases have been reported, and latest evidence points toward a neurodegenerative cause. We describe a 59-year-old female who presented a typical clinical picture of FOSMN over 10 years. Immunological investigations showed positive antinuclear antibodies and antibodies to extractable nuclear antigens (anti-Ro antibodies). A mild inflammatory infiltrate was found on salivary gland biopsy. Intravenous immunoglobulin therapy was effective in improving and then stabilizing this patient's condition. The pathophysiology of FOSMN remains uncertain, and this condition may be heterogeneous. An immune basis cannot be discounted in any given case, and suspected cases merit a trial of immunotherapy.