Colorimetric analysis of the retinal pigmentation

Background: Laguna-ONhE is an application for the colorimetric analysis of optic nerve images, which topographically assesses the cup and the presence of haemoglobin. Its latest version has been fully automated with five deep learning models. In this paper, perimetry in combination with Laguna-ONhE or Cirrus-OCT was evaluated. Methods: The morphology and perfusion estimated by Laguna ONhE were compiled into a “Globin Distribution Function” (GDF). Visual field irregularity was measured with the usual pattern standard deviation (PSD) and the threshold coefficient of variation (TCV), which analyses its harmony without taking into account age-corrected values. In total, 477 normal eyes, 235 confirmed, and 98 suspected glaucoma cases were examined with Cirrus-OCT and different fundus cameras and perimeters. Results: The best Receiver Operating Characteristic (ROC) analysis results for confirmed and suspected glaucoma were obtained with the combination of GDF and TCV (AUC: 0.995 and 0.935, respectively. Sensitivities: 94.5% and 45.9%, respectively, for 99% specificity). The best combination of OCT and perimetry was obtained with the vertical cup/disc ratio and PSD (AUC: 0.988 and 0.847, respectively. Sensitivities: 84.7% and 18.4%, respectively, for 99% specificity). Conclusion: Using Laguna ONhE, morphology, perfusion, and function can be mutually enhanced with the methods described for the purpose of glaucoma assessment, providing early sensitivity.

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Carbon–nitrogen conjugate-composited Cu1.8S with enhanced peroxidase-like activity for the colorimetric detection of hydrogen peroxide and glutathione

Analytical Methods ◽

10.1039/d1ay00166c ◽

2021 ◽

Vol 13 (14) ◽

pp. 1706-1714

Author(s):

Nianlu Li ◽

Mingquan Zhu ◽

Zhenyu Feng ◽

Wenhui Lu ◽

Jing Chen ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Colorimetric Detection ◽

Colorimetric Analysis ◽

Higher Sensitivity

In this work, cystine–glucose Maillard conjugates were composited with Cu1.8S microspheres (Cu1.8S–cgmc) to achieve higher sensitivity for the colorimetric analysis.

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Assessment of Mini-Tablets Coating Uniformity as a Function of Fluid Bed Coater Inlet Conditions

Pharmaceutics ◽

10.3390/pharmaceutics13050746 ◽

2021 ◽

Vol 13 (5) ◽

pp. 746

Author(s):

Magdalena Turk ◽

Rok Šibanc ◽

Rok Dreu ◽

Maja Frankiewicz ◽

Małgorzata Sznitowska

Keyword(s):

Coating Layer ◽

Spectrophotometric Analysis ◽

Material Distribution ◽

Spray Chamber ◽

Colorimetric Analysis ◽

Swirl Generator ◽

Coating Uniformity ◽

Fluid Bed ◽

Inlet Conditions

This study concerned the quality of mini-tablets’ coating uniformity obtained by either the bottom spray chamber with a classical Wurster distributor (CW) or a swirl distributor (SW). Mini-tablets with a diameter of 2.0, 2.5, and 3.0 mm were coated with hypromellose using two different inlet air distributors as well as inlet airflow rates (130 and 156 m3/h). Tartrazine was used as a colorant in the coating layer and the coating uniformity was assessed by spectrophotometric analysis of solutions obtained after disintegration of the mini-tablets (n = 100). Higher uniformity of coating material distribution among the mini-tablets was observed in the case of SW distributor, even for the biggest mini-tablets (d = 3.0 mm), with an RSD no larger than 5.0%. Additionally, coating thickness was evaluated by colorimetric analysis (n = 1000), using a scanner method, and expressed as a hue value. A high correlation (R = 0.993) between inter-tablet variability of hue and UV-Vis results was obtained. Mini-tablets were successfully coated in a fluid bed system using both a classical Wurster distributor as well as a swirl generator. However, regardless of the mini-tablets’ diameter, better film uniformity was achieved in the case of a distributor with a swirl generator.

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Nanotechnology in Roman Opaque Red Glass from the 2nd Century AD. Archaeometric Investigation in Red Sectilia from the Decoration of the Lucius Verus Villa in Rome

Heritage ◽

10.3390/heritage2030159 ◽

2019 ◽

Vol 2 (3) ◽

pp. 2597-2611 ◽

Cited By ~ 1

Author(s):

Mario Bandiera ◽

Patrice Lehuédé ◽

Marco Verità ◽

Luis Alves ◽

Isabelle Biron ◽

...

Keyword(s):

Chemical Composition ◽

Chemical Characterization ◽

Second Step ◽

Colorimetric Analysis ◽

Historical Sources ◽

Pixe Analysis ◽

X Ray ◽

Colorimetric Measurements ◽

Shed Light

This work aims to characterise the chemical composition of Roman opaque red glass sectilia dated to the 2nd century A.D and to shed light on Roman glassmaking production of different shades of red, from red to reddish-brown. Due to the lack of technical historical sources for this period many questions about technological aspects still remain. In this project a multi-disciplinary approach is in progress to investigate the red glass sectilia with several red hues from the Imperial Villa of Lucius Verus (161–169 A.D.) in Rome. First, colorimetric measurements were taken to identify the various red hues. The second step was chemical characterization of the samples and the identification of crystalline colouring phases. Particle Induced X-Ray Emission (PIXE) analysis was used to investigate the chemical composition of these glass samples, while the crystalline phases were identified by Raman Spectroscopy and Scanning Electrons Microscope with Energy Dispersive X-ray Spectrometry (SEM-EDS). Using SEM-EDS nanoparticles were detected as a colouring agent, the chemical composition and the morphology of which has been studied in depth. This information has been compared with the colorimetric analysis to establish any correlation with the different colour hues.

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Progressive Chronic External Ophthalmoplegia with Disorders of Retinal Pigmentation

Ophthalmologica ◽

10.1159/000302981 ◽

1956 ◽

Vol 132 (5) ◽

pp. 298-298 ◽

Cited By ~ 7

Author(s):

J. de Ruyter

Keyword(s):

Retinal Pigmentation

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Rapidly extracted (0.02 M CaCl2-soluble) reactive aluminum as a measure of aluminum toxicity in soils

Soil Research ◽

10.1071/sr9890663 ◽

1989 ◽

Vol 27 (4) ◽

pp. 663 ◽

Cited By ~ 7

Author(s):

EA Close ◽

HKJ Powell

Keyword(s):

Salicylic Acid ◽

White Clover ◽

Aluminum Toxicity ◽

Maximum Yield ◽

Acid Soils ◽

Aluminium Toxicity ◽

Field Method ◽

Colorimetric Analysis ◽

Aluminium Species

This paper examines the use of short extraction times, and the determination of aluminium with chrome azurol S (CAS), for the estimation of 0.02 M CaCl2-soluble aluminium in soils. It reports the correlation between CAS-reactive aluminium in 5 min extracts and percent maximum yield of white clover (Trifolium repens) for a series of acid soils. The reactivity of soluble and colloidal aluminium species with the metallochromic reagent CAS has been assessed. ~ l ( a q ) ~ + , simple hydroxy species and complexes of weakly binding ligands (salicylic acid, tannins) are CAS-reactive (2 rnin). In contrast, complexes of strongly binding ligands (citric acid, fulvic acid) are not CAS-reactive ([Al] ~ [L] ~ [CAS] ~ 1-2~10-5 M). For a series of six limed phosphated topsoils and subsoils (pH 4.2-5.5), 0.02 M CaCl2- soluble aluminium, as determined with CAS, was negatively correlated against the percent maximum yield of white clover; r2 = -0.73** (5 min extraction), n = 20. This correlation is similar to that for yield against total aluminium as determined by atomic absorption spectroscopy after 60 min extraction (r2 = -0.77**). However, the colorimetric analysis is more convenient and sensitive; further, it does not measure colloidal and polymeric aluminium species (which may not be plant-available). The satisfactory correlation achieved for short extraction times suggests use of CAS for a rapid field method for aluminium toxicity in soils.

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