Anatomical analysis of turgescent and semi‐dry resurrection plants: The effect of sample preparation on the sample, resolution, and image quality of X‐ray micro‐computed tomography (μCT)

2010 ◽  
Vol 74 (4) ◽  
pp. 364-369 ◽  
Author(s):  
Nikola Korte ◽  
Stefan Porembski
Keyword(s):  
Computed Tomography ◽  
Image Quality ◽  
Sample Preparation ◽  
Resurrection Plants ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Anatomical Analysis

Typical errors when performing intraoral periapical x-rays, and their effect on image quality

2020 ◽  
pp. 36-44
Author(s):  
A.P. Arzhantsev
Keyword(s):  
Computed Tomography ◽  
Image Quality ◽  
Digital Image ◽  
Cone Beam ◽  
X Rays ◽  
Post Processing ◽  
X Ray ◽  
Selection Of ◽  
Periapical Radiography

During the study, intraoral periapical images were analyzed in 300 patients. The possibilities of using the methods of radiography and their influence on the quality of the obtained x-ray images were studied. The intraoral periapical radiography was compared with the results of orthopantomography and cone beam computed tomography. To identify the features of the mapping of zones of periapical destruction, 47 experimental x-ray studies were performed on skeletonized jaws with artificial defects in cortical plates. Often encountered errors are: an arbitrary choice of angles of inclination and the centration of the x-ray tube, the wrong location of the x-ray receiver in the patient's mouth, inaccurate installation or poor fixation of the patient's head, inefficient selection of physical and technical conditions of shooting, non-compliance with the conditions of the photo process with analog radiography or post-processing and printing digital image. The characteristic projection distortions of images resulting from these errors are analyzed and illustrated.

scholarly journals Results of the clinical evaluation of the low-dose protocols of the digital linear tomography of the chest

2020 ◽  
Vol 13 (1) ◽  
pp. 47-59
Author(s):  
I. G. Kamyshanskaya ◽  
V. M. Cheremisin ◽  
A. V. Vodovatov ◽  
A. N. Boriskina
Keyword(s):  
Computed Tomography ◽  
Image Quality ◽  
Early Treatment ◽  
Low Dose ◽  
Image Quality Assessment ◽  
Treatment Center ◽  
X Ray ◽  
Second Stage ◽  
Patient Doses

High levels of tuberculosis morbidity in the Russian Federation lead to the extensive use of X-ray diagnostics for the tuberculosis screening and assessment of the effectiveness of treatment. Digital radiography and computed tomography are traditionally used for the diagnostics of tuberculosis. These methods are associated with significant drawbacks: low specificity for radiography, high costs per examination, significant patient doses, and limited availability for computed tomography. As an additional method for the assessment of the effectiveness of the tuberculosis treatment it is possible to use linear tomography performed on the digital X-ray units. The aim of the current study was to evaluate the possibility of utilization of the digital linear tomography for the control of the effectiveness of tuberculosis treatment in a dedicated antitubercular medical facility. The study was divided in two stages. The first stage was aimed at the assessment of the diagnostic image quality of the digital linear tomograms obtained using the previously developed low-dose imaging protocols. Image quality assessment was performed using an anthropomorphic chest phantom and dedicated imitators of the lung lesions. Image quality was assessed by the experts (radiologists) based on the developed image quality criteria. Results of the first stage of the study indicate that all low-dose protocols allow obtaining images with at least acceptable image quality. Hence it was possible to propose low-dose protocols for clinical evaluations. The second stage of the study was performed as a prospective cohort survey aimed at the evaluation of the structure of X-ray examinations, patient doses and clinical image quality of the digital linear tomograms in antitubercular early treatment center. The cohort survey included two patient samples, uniform by age and gender composition, anthropometric characteristics and structure of diagnosis. One of the samples was imaged using standard (vendor) digital linear protocols, other – using the proposed low-dose protocols. Dose data collection (measurement of dose-area product and subsequent calculation of effective dose) and expert image quality assessment was performed for each patient. The results of the second stage of the study indicate that the use of the low-dose protocols allow reducing the patient effective doses per examination up to a factor of 6–8 (0.56 – 5.9 mSv for standard protocols; 0.2 – 1.15 mSv for low-dose protocols) due to the reduction in tube current-time product (126 mean mAs and 11 mean mAs, respectively). The dose reduction is accompanied by the reduction in the image quality of the linear tomograms (from “excellent” or “good” for standard protocols to “acceptable” for low-dose protocols). However, that dose not hinder the conclusion decision and identification of pathologies. Results of the study indicate that digital linear tomography can be used for the evaluation of the dynamics of the pathological process in the lungs with the previously defined localization of the pathology. The presented low-dose protocols were implemented into radiological practice of the antitubercular early treatment center. Currently, the proposed low-dose protocols are under evaluation for the large-scale study on the base of general practice hospitals

Pretreatment and Freezing Rate Effect on Physical, Microstructural, and Nutritional Properties of Fried Sweet Potato

2019 ◽  
Vol 62 (1) ◽  
pp. 45-59 ◽  
Author(s):  
Ahmed Rady ◽  
Ahmed Rady ◽  
Andrew Giaretta ◽  
Adedeji Akinbode ◽  
Mathew Ruwaya ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Vitamin C ◽  
Sweet Potato ◽  
Freezing Rate ◽  
Micro Computed Tomography ◽  
Surface Pretreatment ◽  
X Ray ◽  
C 30 ◽  
Fat Uptake

Abstract. Sweet potato is a unique high-calorie food because it is an excellent source of some essential micronutrients, such as provitamin A (ß-carotene). The quality of par-fried frozen sweet potato products is impacted by several factors that have not been well researched, such as freezing rate and surface modification. In this study, our objective was to evaluate the effect of freezing rate (at -20°C, -30°C, -40°C, and -60°C), surface pretreatment including blanching and gum coating (methylcellulose, sodium alginate, or mixed gums), sample dimensions (strips or slices), and cultivar (Covington and Murasaki) on several quality attributes of fried sweet potato. Based on our study, frying at 180°C yielded the lowest oil content among the tested temperatures. Compared with Covington samples, Murasaki strips coated with mixed gums produced fried samples that were significantly (p = 0.05) lower in fat uptake (10.84%), less porous (35.5%), crispier (maximum force = 6.90 N), lighter, less red, and yellower. Higher freezing rate, 5.12°C min-1 (at -60°C), showed significantly lower fat content, and lower lightness or yellowness than lower freezing rates. Frying at 180°C significantly reduced vitamin C and ß-carotene levels from 3.75 mg and 349.27 µg per 100 g to 1.92 mg and 105.99 µg per 100 g, respectively. X-ray micro-computed tomography showed a significant decrease in porosity because of high freezing rates. The general conclusion is that faster freezing rate is better for par-fried sweet potato quality preservation. Keywords: ß-carotene, Fat uptake, Gum coating, Par-frying, Sweet potato, X-ray micro-computed tomography, Vitamin C.

Morphology and Affinities of Ampelocissites Seeds (Vitaceae: Ampelopsis clade) from the Paleogene of Texas, USA

2020 ◽  
Vol 45 (3) ◽  
pp. 478-482
Author(s):  
Steven R. Manchester
Keyword(s):  
Computed Tomography ◽  
Cross Sections ◽  
Seed Coat ◽  
Ct Scanning ◽  
Seed Morphology ◽  
Early Eocene ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Fossil Seeds ◽  
Fossil Genus

Abstract—The type material on which the fossil genus name Ampelocissites was established in 1929 has been reexamined with the aid of X-ray micro-computed tomography (μ-CT) scanning and compared with seeds of extant taxa to assess the relationships of these fossils within the grape family, Vitaceae. The specimens were collected from a sandstone of late Paleocene or early Eocene age. Although originally inferred by Berry to be intermediate in morphology between Ampelocissus and Vitis, the newly revealed details of seed morphology indicate that these seeds represent instead the Ampelopsis clade. Digital cross sections show that the seed coat maintains its thickness over the external surfaces, but diminishes quickly in the ventral infolds. This feature, along with the elliptical chalaza and lack of an apical groove, indicate that Ampelocissites lytlensis Berry probably represents Ampelopsis or Nekemias (rather than Ampelocissus or Vitis) and that the generic name Ampelocissites may be useful for fossil seeds with morphology consistent with the Ampelopsis clade that lack sufficient characters to specify placement within one of these extant genera.

INVESTIGATION OF AUBRITES THROUGH INTEGRATION OF 3D MODAL MINERALOGY WITH X-RAY MICRO-COMPUTED TOMOGRAPHY AND GEOCHEMISTRY

2018 ◽  
Author(s):  
Zoë E. Wilbur ◽  
◽  
Arya Udry ◽  
Arya Udry ◽  
Daniel M. Coleff ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Micro Computed Tomography ◽  
X Ray

scholarly journals Investigation of opening eye defects and effects of different ripening profiles on eye structure in semi-hard cheese using X-ray micro-computed tomography

2021 ◽  
Vol 28 ◽  
pp. 100190
Author(s):  
Jaqueline Auer ◽  
Michael Reiter ◽  
Sascha Senck ◽  
Andreas Reiter ◽  
Johann Kastner ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Hard Cheese
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