Search results for "PIGMENT"

Indoor lighting quality: Effects of different wall colours

2016

This paper reports the results of measurements performed in a test room to investigate the impact of using different wall colours and light scenes on indoor lighting quality. Eye level spectral irradiances were measured for a user located inside the room and seated at a desk. These measurements allow the use of the Irradiance Toolbox, which makes it possible to calculate equivalent illuminances for the photopigments in the human eye. Moreover, the CIECAM02 colour appearance model was used to investigate the variations in hue and chroma values of the different wall colours when changing the light scene. The results demonstrate that there are significant variations in eye level spectral irra…

Preliminary results on the historical production of majolica tiles in the Madonie area (Northern Central Sicily)

2007

Isolation and Characterization of an Fe(III)-Chelating Compound Produced by Pseudomonas syringae

1986

The phytopathogenic bacterium Pseudomonas syringae produces a fluorescent pigment when it is grown in iron-deficient media. This pigment forms a very stable Fe(III) complex that was purified in this form by using a novel procedure based on ultrafiltration and column chromatography. The Fe(III) complex has a molecular weight of 1,100 and contains 1 mol of Fe(III). The pigment is composed of an amino acid moiety with three threonines, three serines, one lysine, δ- N -hydroxyornithine, and a quinoline-type fluorescent chromophore. These features and its stability constant (in the range of 10 32 ) suggest that the fluorescent pigment of P. syringae is related to the siderophores produced by an…

Involvement of nitrate reductase and pyoverdine in competitiveness of Pseudomonas fluorescens strain C7R12 in soil

2001

ABSTRACT Involvement of nitrate reductase and pyoverdine in the competitiveness of the biocontrol strain Pseudomonas fluorescens C7R12 was determined, under gnotobiotic conditions, in two soil compartments (bulk and rhizosphere soil), with the soil being kept at two different values of matric potential (−1 and −10 kPa). Three mutants affected in the synthesis of either the nitrate reductase (Nar − ), the pyoverdine (Pvd − ), or both (Nar − Pvd − ) were used. The Nar − and Nar − Pvd − mutants were obtained by site-directed mutagenesis of the wild-type strain and of the Pvd − mutant, respectively. The selective advantage given by nitrate reductase and pyoverdine to the wild-type strain was as…

Missense and nonsense mutations in melanocortin 1 receptor (MC1R) gene of different goat breeds: association with red and black coat colour phenotype…

2009

Abstract Background Agouti and Extension loci control the relative amount of eumelanin and pheomelanin production in melanocytes that, in turn, affects pigmentation of skin and hair. The Extension locus encodes the melanocortin 1 receptor (MC1R) whose permanent activation, caused by functional mutations, results in black coat colour, whereas other inactivating mutations cause red coat colour in different mammals. Results The whole coding region of the MC1R gene was sequenced in goats of six different breeds showing different coat colours (Girgentana, white cream with usually small red spots in the face; Maltese, white with black cheeks and ears; Derivata di Siria, solid red; Murciano-Granad…

Novel silicon microparticles to improve sunlight stability of raw polypropylene

2015

Oxidation of polyolefins by ultraviolet/visible irradiation is a significant limitation for their use in several technological applications. The use of high-tech additives such as silicon microparticles becomes a compositing strategy that can improve the performance of these materials at long-term service conditions. Silicon particles were added to non-additivated raw polypropylene (PP) prepared by hot melt extrusion and subjected to accelerated sunlight irradiation tests. The stability of thermal properties, mechanical performance and thermal decomposition behaviour of composites was evaluated by differential scanning calorimetry, dynamic mechanical thermal analysis and thermogravimetry. T…

Nodular Lesion in Cheek With a Hair Tuft

2017

Trichostasis spinulosa is a rarely diagnosed disorder of the pilosebaceous unit, characterized by retention of telogen hairs within the dilated follicles. A hair tuft can be seen protruding from the follicles. We present a case of trichostasis spinulosa associated with intradermal melanocytic nevi, where dermoscopy helps to identify this entity.

CCDC 737338: Experimental Crystal Structure Determination

2009

Related Article: M.U.Schmidt, S.Bruhne, A.K.Wolf, A.Rech, J.Bruning, E.Alig, L.Fink, C.Buchsbaum, J.Glinnemann, J.van de Streek, F.Gozzo, M.Brunelli, F.Stowasser, T.Gorelik, E.Mugnaioli, U.Kolb|2009|Acta Crystallogr.,Sect.B:Struct.Sci.|65|189|doi:10.1107/S0108768109003759

CRYPTIC SPECIES RELATED TO DALDINIA CONCENTRICA AND D. ESCHSCHOLZII, WITH NOTES ON D. BAKERI

2004

Daldinia macaronesica (from the Canary Islands and Madeira), D. palmensis (from the Canary Islands), D. martinii and D. raimundi (from Sicily), and D. vanderguchtiae (from Jersey, Channel Islands) spp. nov., are described, based on new combinations of teleomorphic and anamorphic characters. They all resemble the pantropical D. eschscholzii and/or the European D. concentrica with regard to teleomorphic characters and secondary metabolite profiles generated by analytical HPLC. The status of the newly described taxa was established by SEM of ascospores and microscopic studies of their anamorphs in comparison with various materials of the aforementioned known species. HPLC and SEM studies on th…

Pigmentazioni dentarie da clorexidina: una revisione critica

2020

OBIETTIVI Obiettivo di questo lavoro è proporre una revisione critica della letteratura sulle pigmentazioni orali indotte dalla clorexidina, in particolare sul meccanismo di formazione delle pigmentazioni, sulla loro prevalenza, sui fattori che ne influenzano l’insorgenza e la gravità e sull’efficacia clinica del sistema antipigmentazione a base di sodio metabisolfito e di acido ascorbico (ADS). MATERIALI E METODI È stata effettuata una ricerca bibliografica utilizzando in combinazione le seguenti parole chiave: Chlorhexidine, Mouthwash, Staining, Anti-Discoloration System, Gingivitis, Plaque. Sono stati presi in considerazione articoli scientifici e revisioni della letteratura in inglese, …