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Albinism is a genetic disorder that results in a deficiency in melanin production. This type of chromatic alteration may affect several vertebrate species, but is rarely observed in nature. In Brazil, for the bat group, only 15 albino individuals have been registered. Here we present a new case for Artibeus planirostris. A pregnant female of this species with alopecia was captured in the Caatinga biome. A compilation of the distribution of albino bats in Brazil is presented.

The National Mall is the great promenade that connects the most important buildings of the capital of the United States: the capitol with the George Washington and Abraham Lincoln Memorials touring the Castle and the main Smithsonian museums and the National Gallery of Art. The fountains present inside and outside these museums suffer alterations of color and texture due to colonization of algal populations on the surface of their constituent materials. We have studied 9 fountain belonging to the National Gallery of Art, the Smithsonian National Museum of African American History and Culture, the Smithsonian Museum of Contemporary Art (Hirshhorn), the Smithsonian Arts and Industries Building, the Smithsonian Institution Building (the Castle), the Smithsonian National Museum of American History and the Smithsonian National Museum of the American Indian. In this work carried out by the national Project VIRARTE (UGR-MEC) at the Smithsonian Museum Conservation Institute (MCI-SI), the relationship between the diversity of the algal groups and the material composition and typology of the fountains is studied. We have studied the presence of different species of green microalgae, blue-green microalgae and diatoms that form pustules, films, mats and mineral crusts on fountains constructed with granite, limestone and various metals, and even upon sealant resins that are used to repair water leaks. The ultimate goal of this work in the control of these formations to avoid the aesthetic, functional and material damage that these photosynthetic organisms produce in the architectural heritage associated with water., Universidad de Granada Ayuntamiento de Granada Patronato de la Alhambra y Generalife. Consejería de Cultura Escuela Técnica Superior de Ingeniería de Edificación de la Universidad de Granada Turismo Ciudad de Granada. Ayuntamiento de Granada

The National Mall is the great promenade that connects the most important buildings of the capital of the United States: the capitol with the George Washington and Abraham Lincoln Memorials touring the Castle and the main Smithsonian museums and the National Gallery of Art. The fountains present inside and outside these museums suffer alterations of color and texture due to colonization of algal populations on the surface of their constituent materials. We have studied 9 fountain belonging to the National Gallery of Art, the Smithsonian National Museum of African American History and Culture, the Smithsonian Museum of Contemporary Art (Hirshhorn), the Smithsonian Arts and Industries Building, the Smithsonian Institution Building (the Castle), the Smithsonian National Museum of American History and the Smithsonian National Museum of the American Indian. In this work carried out by the national Project VIRARTE (UGR-MEC) at the Smithsonian Museum Conservation Institute (MCI-SI), the relationship between the diversity of the algal groups and the material composition and typology of the fountains is studied. We have studied the presence of different species of green microalgae, blue-green microalgae and diatoms that form pustules, films, mats and mineral crusts on fountains constructed with granite, limestone and various metals, and even upon sealant resins that are used to repair water leaks. The ultimate goal of this work in the control of these formations to avoid the aesthetic, functional and material damage that these photosynthetic organisms produce in the architectural heritage associated with water. Universidad de Granada Ayuntamiento de Granada Patronato de la Alhambra y Generalife. Consejería de Cultura Escuela Técnica Superior de Ingeniería de Edificación de la Universidad de Granada Turismo Ciudad de Granada. Ayuntamiento de Granada

Lead-containing pigments (red lead, white lead), widely employed in paintings since Antiquity, are liable to undergo transformations which lead to discolorations of the pictorial layer (blackening, whitening, greening). The conditions of appearing of the alteration phases are studied through artificial ageing tests of raw pigments and experimental paintings. The tests reveal both the decomposition of white lead in the presence of lime and the transformation of minium into black plattnerite b-PbO2 in dilute acidic environment. The characterization of red lead micro-samples taken from an experimental wall painting after a 25-years natural ageing period reveal that blackening is linked to the formation of plattnerite through a probable mechanism of disproportionnation of Pb3O4 in acidic environment. The whitening is cause by the re-crystallization of divalent lead into both cerusite (PbCO3) and anglesite (PbSO4), produced by the absorption of gaseous pollutants (CO2, SO2).; Les pigments au plomb (minium, céruse), couramment employés en peinture depuis l'Antiquité, sont connus pour subir des transformations entraînant des décolorations de la couche picturale (noircissement, blanchissement, verdissement). Les conditions de stabilité des pigments sont étudiées par des essais de vieillissement artificiels de pigments bruts et d'éprouvettes peintes. Ceux-ci montrent la décomposition de l'hydrocérusite en présence de chaux ainsi que la transformation de Pb3O4 en plattnérite (b-PbO2) en milieu acide dilué. La caractérisation d'échantillons de minium prélevés sur un peinture murale expérimentale après 25 ans de vieillissement naturel révèle que le noircissement du minium est lié à la formation de plattnérite par un mécanisme possible de disproportionnation de Pb3O4 en milieu acide. Leblanchissement est dû à la recristallisation du plomb divalent sous forme de cérusite (PbCO3) et d'anglésite (PbSO4), causée par l'absorption de polluants gazeux (CO2, SO2).

Lead-containing pigments (red lead, white lead), widely employed in paintings since Antiquity, are liable to undergo transformations which lead to discolorations of the pictorial layer (blackening, whitening, greening). The conditions of appearing of the alteration phases are studied through artificial ageing tests of raw pigments and experimental paintings. The tests reveal both the decomposition of white lead in the presence of lime and the transformation of minium into black plattnerite b-PbO2 in dilute acidic environment. The characterization of red lead micro-samples taken from an experimental wall painting after a 25-years natural ageing period reveal that blackening is linked to the formation of plattnerite through a probable mechanism of disproportionnation of Pb3O4 in acidic environment. The whitening is cause by the re-crystallization of divalent lead into both cerusite (PbCO3) and anglesite (PbSO4), produced by the absorption of gaseous pollutants (CO2, SO2).; Les pigments au plomb (minium, céruse), couramment employés en peinture depuis l'Antiquité, sont connus pour subir des transformations entraînant des décolorations de la couche picturale (noircissement, blanchissement, verdissement). Les conditions de stabilité des pigments sont étudiées par des essais de vieillissement artificiels de pigments bruts et d'éprouvettes peintes. Ceux-ci montrent la décomposition de l'hydrocérusite en présence de chaux ainsi que la transformation de Pb3O4 en plattnérite (b-PbO2) en milieu acide dilué. La caractérisation d'échantillons de minium prélevés sur un peinture murale expérimentale après 25 ans de vieillissement naturel révèle que le noircissement du minium est lié à la formation de plattnérite par un mécanisme possible de disproportionnation de Pb3O4 en milieu acide. Leblanchissement est dû à la recristallisation du plomb divalent sous forme de cérusite (PbCO3) et d'anglésite (PbSO4), causée par l'absorption de polluants gazeux (CO2, SO2).