In Romanesque wall paintings in Aragon (Spain), the pigment used for creating blue was a very characteristic mineral, aerinite, which came from local ores in the southern Pyrenees. Optical and scanning electron microscopy (SEM), with energy-dispersive X-ray (EDX) analysis, X-ray diffraction, and reflectance spectroscopy were used to make a detailed microcharacterization of this rare blue pigment in order to improve the knowledge of its composition and possible variability, from samples of medieval paintings and some mineral ores. New analytical data on the chemical composition of the blue pigment are reported here, together with the characterization of its microstructure, and the heterogeneity of the natural pigment made by the features of the ore itself. X-ray diffraction pattern and color parameters of the mineral ores are also included. The data obtained by SEM-EDX will assist identification of this pigment by electron microscopy. The natural variability in composition observed in the samples may be used to explain formation of the extracted mineral and to compare several ore sources. Connection of the ore composition with the pigments used in Romanesque wall paintings will help both provenance and attribution studies.
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http://dx.doi.org/10.1017/S1431927613013391 | DOI Listing |
Cancers (Basel)
January 2025
Department of Dermatology, Institute of Medical Sciences, Medical College, Rzeszow University, 35-310 Rzeszow, Poland.
Basal cell carcinoma (BCC) is the most prevalent type of skin cancer worldwide. Despite its low metastatic potential, certain subtypes present an aggressive clinical course. Part II focuses on the different dermoscopic patterns observed in BCC, depending on the lesion subtype, its location on the body, the patient's age, the size of the tumor, and skin phototype.
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January 2025
Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA Faculty of Sciences and Technology, NOVA University of Lisbon, Campus Caparica, 2829-516 Caparica, Portugal.
Pigment production has a substantial negative impact on the environment, since mining for natural pigments causes ecosystem degradation, while synthetic pigments, derived from petrochemicals, generate toxic by-products that accumulate and persist in aquatic systems due to their resistance to biodegradation. Despite these challenges, pigments remain essential across numerous industries, including the cosmetic, textile, food, automotive, paints and coatings, plastics, and packaging industries. In response to growing consumer demand for sustainable options, there is increasing interest in eco-friendly alternatives, particularly bio-based pigments derived from algae, fungi, and actinomycetes.
View Article and Find Full Text PDFMetabolites
December 2024
Department of Crop Science, College of Agriculture, Life and Environment Sciences, Chungbuk National University, Cheongju 28644, Republic of Korea.
Chlorophyll is the primary pigment responsible for capturing light energy during photosynthesis, while carotenoids assist in light absorption and provide photoprotection by dissipating excess energy. Both pigments are essential for plant growth and development, playing distinct and complementary roles in maintaining photosynthetic efficiency and protecting plants from oxidative stress. Because of their function in photosynthesis and photoprotection, chlorophyll and carotenoid accumulation are strongly associated with light conditions, especially blue and red lights, which play key roles in regulating their metabolisms.
View Article and Find Full Text PDFFront Physiol
January 2025
Regenerative Medicine Division, CHU de Quebec - Université Laval Research Centre, Quebec City, QC, Canada.
Introduction: Recent findings show that visible light, particularly blue light, stimulates melanogenesis in human skin, though the underlying mechanisms remain debated. This study aimed to determine the cell damage threshold of non-ionizing blue light on keratinocytes while preserving their ability to stimulate melanogenesis.
Methods: Human keratinocytes (N = 3) and melanocytes (N = 3) were isolated from skin samples of varying Fitzpatrick skin phototypes and irradiated with blue light (λpeak = 457 nm) and UVA light (λpeak = 385 nm).
Hum Mol Genet
January 2025
Department of Facial Plastic and Reconstructive Surgery, ENT Institute, Eye & ENT Hospital, Fudan University, No. 83 Fenyang Road, Xuhui District, Shanghai 200031, China.
Waardenburg syndrome type 2 (WS2) is an autosomal dominant disorder characterized by congenital sensorineural hearing loss, blue iris, and abnormal pigmentation of the hair and skin. WS2 is genetically heterogeneous, often resulting from pathogenic mutations in SOX10 gene. We identified a novel heterozygous frameshift mutation in SOX10 (NM_006941.
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