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Enrique J. Baran - One of the best experts on this subject based on the ideXlab platform.
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ir spectroscopic characterization of biominerals in marattiaceaeus ferns
Brazilian Journal of Botany, 2010Co-Authors: Enrique J. Baran, Cristina Hilda RolleriAbstract:(Caracterizacao de biominerais por espectroscopia infravermelha em Marattiaceae). Mostras de frondes dos fetos eusporangiados dos generos Angiopteris, Christensenia, Danaea e Marattia (Marattiaceae), foram investigadas por espectroscopia infravermelha sob diferentes condicoes experimentais. Os resultados confirmaram relatos anteriores sobre a acumulacao de silica biogenica (SiO2), em tecidos desses fetos e tambem mostraram, pela primeira vez, a presenca de oxalato de calcio nesse grupo de plantas, provavelmente na forma de Weddellite. A capacidade de mineralizar SiO2, para produzir e acumular silica biogenica, sugere que esta caracteristica seja uma propriedade generica dos membros da familia Marattiaceae.
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Characterization of Calcium Oxalates Generated as Biominerals in Cacti
Plant physiology, 2002Co-Authors: Paula V. Monje, Enrique J. BaranAbstract:The chemical composition and morphology of solid material isolated from various Cactaceae species have been analyzed. All of the tested specimens deposited high-purity calcium oxalate crystals in their succulent modified stems. These deposits occurred most frequently as round-shaped druses that sometimes coexist with abundant crystal sand in the tissue. The biominerals were identified either as CaC2O4.2H2O (Weddellite) or as CaC2O4.H2O (whewellite). Seven different species from the Opuntioideae subfamily showed the presence of whewellite, and an equal number of species from the Cereoideae subfamily showed the deposition of Weddellite. The chemical nature of these deposits was assessed by infrared spectroscopy. The crystal morphology of the crystals was visualized by both conventional light and scanning electron microscopy. Weddellite druses were made up of tetragonal crystallites, whereas those from whewellite were most often recognized by their acute points and general star-like shape. These studies clearly demonstrated that members from the main traditional subfamilies of the Cactaceae family could synthesize different chemical forms of calcium oxalate, suggesting a definite but different genetic control. The direct relationship established between a given Cactaceae species and a definite calcium oxalate biomineral seems to be a useful tool for plant identification and chemotaxonomy.
Bárcenas Argüello, María Luisa - One of the best experts on this subject based on the ideXlab platform.
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Distribución ecológica del subgénero Neodawsonia Backeb. del género Cephalocereus Pfeiff. (Cactaceae), en el Itsmo de Tehuantepec, México.
Colegio de Postgraduados (COLPOS), 2011Co-Authors: Bárcenas Argüello, María LuisaAbstract:Cephalocereus es un género monofilético, cuya distribución es alopátrica y está restringida a la Barranca de Metztitlán (C. senilis), al Valle de Tehuacán-Cuicatlán (C. columna-trajani) y a la cuenca del río Tehuantepec (subgénero Neodawsonia, C. apicicephalium, C. nizandensis, C. totolapensis). Se desconoce qué factores condicionan este patrón de distribución endémico. El objetivo de este trabajo fue el proponer una hipótesis que explique el endemismo de sus especies, a partir de relaciones específicas entre la fisiología de los oxalatos de calcio y las propiedades de las rocas y de los suelos en los que habitan. En cada población se tomaron muestras del material parental (roca) del suelo, se removió tejido vegetal y se recolectaron semillas; estas muestras fueron analizadas con diferentes técnicas de microscopia, análisis físico-químicos y rayos X. La distribución de las especies del subgénero Neodawsonia está restringida por el tipo del material parental (roca) y el ambiente edáfico (suelo) con bajo contenido de calcio soluble. Las especies acumulan weddellita en dos estados de hidratación altamente polimórfica, que se sintetiza a partir de los siete días de edad. El rápido proceso de germinación (24 horas) y la acumulación temprana de cristales podrían ser respuestas de supervivencia. El análisis de parsimonia reveló que el ancestro de Cephalocereus habitaba a menos de 1,370 metros de altitud, con temperatura máxima de 32 ºC y precipitación mínima de 17 mm. La evolución in situ de cada una de las especies de Cephalocereus se relacionó a condiciones del material parental y del suelo sui generis (edáficas particulares) que permiten explicar su endemismo. _______________ ECOLOGICAL DISTRIBUTION OF Neodawsonia Backeb. (Cephalocereus Pfeiff., CACTACEAE), IN THE ISTHMUS OF TEHUANTEPEC, MEXICO. ABSTRACT: Cephalocereus is a monophyletic genus, whose distribution is allopatric and restricted to Metztitlán Canyon (C. senilis), Tehuacán-Cuicatlán valley (C. columna-trajani), and Tehuantepec River basin (subgenus Neodawsonia, C. apicicephalium, C. nizandensis, C. totolapensis). Is not known what factors determine this distribution pattern of endemicity. The aim of this study was to propose a hypothesis to explain the endemism of their species, based on specific relationships between the physiology of calcium oxalate and the properties of rocks and soils in which they live. In each population parent material (rock) soil was sampled, plant tissue was removed, and seeds were collected. Those samples were analyzed with various microscopy techniques, physic-chemical analysis and X-rays. The distribution of the subgenus Neodawsonia is restricted by the type of parent material (rock) and the soil environment (soil) with low content of soluble calcium. The species accumulated Weddellite in two highly polymorphic states of hydration, which is synthesized from seven days old. The rapid process of germination (24 hours) and the early accumulation of crystals could be both a survival responseThe parsimony analysis revealed that Cephalocereus ancestor lived in an elevation less than 1,370 meters, 32 ºC of maximum temperature, and 17 mm of low rainfall. In situ evolution of each species of Cephalocereus was related to the parental material and soil sui generis which allow to explaining their endemicity
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Distribución ecológica del subgénero Neodawsonia Backeb. del género Cephalocereus Pfeiff. (Cactaceae), en el Itsmo de Tehuantepec, México.
Colegio de Postgraduados (COLPOS), 2011Co-Authors: Bárcenas Argüello, María LuisaAbstract:Cephalocereus es un género monofilético, cuya distribución es alopátrica y está restringida a la Barranca de Metztitlán (C. senilis), al Valle de Tehuacán-Cuicatlán (C. columna-trajani) y a la cuenca del río Tehuantepec (subgénero Neodawsonia, C. apicicephalium, C. nizandensis, C. totolapensis). Se desconoce qué factores condicionan este patrón de distribución endémico. El objetivo de este trabajo fue el proponer una hipótesis que explique el endemismo de sus especies, a partir de relaciones específicas entre la fisiología de los oxalatos de calcio y las propiedades de las rocas y de los suelos en los que habitan. En cada población se tomaron muestras del material parental (roca) del suelo, se removió tejido vegetal y se recolectaron semillas; estas muestras fueron analizadas con diferentes técnicas de microscopia, análisis físico-químicos y rayos X. La distribución de las especies del subgénero Neodawsonia está restringida por el tipo del material parental (roca) y el ambiente edáfico (suelo) con bajo contenido de calcio soluble. Las especies acumulan weddellita en dos estados de hidratación altamente polimórfica, que se sintetiza a partir de los siete días de edad. El rápido proceso de germinación (24 horas) y la acumulación temprana de cristales podrían ser respuestas de supervivencia. El análisis de parsimonia reveló que el ancestro de Cephalocereus habitaba a menos de 1,370 metros de altitud, con temperatura máxima de 32 ºC y precipitación mínima de 17 mm. La evolución in situ de cada una de las especies de Cephalocereus se relacionó a condiciones del material parental y del suelo sui generis (edáficas particulares) que permiten explicar su endemismo. _______________ ECOLOGICAL DISTRIBUTION OF Neodawsonia Backeb. (Cephalocereus Pfeiff., CACTACEAE), IN THE ISTHMUS OF TEHUANTEPEC, MEXICO. ABSTRACT: Cephalocereus is a monophyletic genus, whose distribution is allopatric and restricted to Metztitlán Canyon (C. senilis), Tehuacán-Cuicatlán valley (C. columna-trajani), and Tehuantepec River basin (subgenus Neodawsonia, C. apicicephalium, C. nizandensis, C. totolapensis). Is not known what factors determine this distribution pattern of endemicity. The aim of this study was to propose a hypothesis to explain the endemism of their species, based on specific relationships between the physiology of calcium oxalate and the properties of rocks and soils in which they live. In each population parent material (rock) soil was sampled, plant tissue was removed, and seeds were collected. Those samples were analyzed with various microscopy techniques, physic-chemical analysis and X-rays. The distribution of the subgenus Neodawsonia is restricted by the type of parent material (rock) and the soil environment (soil) with low content of soluble calcium. The species accumulated Weddellite in two highly polymorphic states of hydration, which is synthesized from seven days old. The rapid process of germination (24 hours) and the early accumulation of crystals could be both a survival responseThe parsimony analysis revealed that Cephalocereus ancestor lived in an elevation less than 1,370 meters, 32 ºC of maximum temperature, and 17 mm of low rainfall. In situ evolution of each species of Cephalocereus was related to the parental material and soil sui generis which allow to explaining their endemicity.Tesis (Doctorado en Ciencias, especialista en Botánica).- Colegio de Postgraduados, 2011.Consejo Nacional de Ciencia y Tecnología (CONACyT)
Barán, Enrique José - One of the best experts on this subject based on the ideXlab platform.
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Characterization of calcium oxalates generated as biominerals in cacti
2019Co-Authors: Monje Paula, Barán, Enrique JoséAbstract:The chemical composition and morphology of solid material isolated from various Cactaceae species have been analyzed. All of the tested specimens deposited high-purity calcium oxalate crystals in their succulent modified stems. These deposits occurred most frequently as round-shaped druses that sometimes coexist with abundant crystal sand in the tissue. The biominerals were identified either as CaC 2 O 4 .2H 2 O (Weddellite) or as CaC 2 O 4 .H 2 O (whewellite). Seven different species from the Opuntioideae subfamily showed the presence of whewellite, and an equal number of species from the Cereoideae subfamily showed the deposition of Weddellite. The chemical nature of these deposits was assessed by infrared spectroscopy. The crystal morphology of the crystals was visualized by both conventional light and scanning electron microscopy. Weddellite druses were made up of tetragonal crystallites, whereas those from whewellite were most often recognized by their acute points and general star-like shape. These studies clearly demonstrated that members from the main traditional subfamilies of the Cactaceae family could synthesize different chemical forms of calcium oxalate, suggesting a definite but different genetic control. The direct relationship established between a given Cactaceae species and a definite calcium oxalate biomineral seems to be a useful tool for plant identification and chemotaxonomy.Centro de Química Inorgánic
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Caracterização de biominerais por espectroscopia infravermelha em Marattiaceae
2014Co-Authors: Barán, Enrique José, Rolleri, Cristina HildaAbstract:Frond samples of the eusporangiate ferns Marattiaceae genera Angiopteris, Christensenia, Danaea and Marattia were investigated by infrared spectroscopy, under different experimental conditions. The results confirmed the previously reported accumulation of biogenic silica (SiO2) in tissues of these ferns and also showed, for the first time, the presence of calcium oxalate in this group of plants, probably as Weddellite. The ability to biomineralize SiO2, to produce and accumulate biogenic silica, is suggested now to be a general family trait of the Marattiaceae.Facultad de Ciencias Naturales y Muse
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Caracterização de biominerais por espectroscopia infravermelha em Marattiaceae
2014Co-Authors: Barán, Enrique José, Rolleri, Cristina HildaAbstract:Frond samples of the eusporangiate ferns Marattiaceae genera Angiopteris, Christensenia, Danaea and Marattia were investigated by infrared spectroscopy, under different experimental conditions. The results confirmed the previously reported accumulation of biogenic silica (SiO2) in tissues of these ferns and also showed, for the first time, the presence of calcium oxalate in this group of plants, probably as Weddellite. The ability to biomineralize SiO2, to produce and accumulate biogenic silica, is suggested now to be a general family trait of the Marattiaceae.Laboratorio de Estudios de Anatomía Vegetal Evolutiva y SistemáticaCentro de Química Inorgánic
Rolleri, Cristina Hilda - One of the best experts on this subject based on the ideXlab platform.
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Caracterização de biominerais por espectroscopia infravermelha em Marattiaceae
2014Co-Authors: Barán, Enrique José, Rolleri, Cristina HildaAbstract:Frond samples of the eusporangiate ferns Marattiaceae genera Angiopteris, Christensenia, Danaea and Marattia were investigated by infrared spectroscopy, under different experimental conditions. The results confirmed the previously reported accumulation of biogenic silica (SiO2) in tissues of these ferns and also showed, for the first time, the presence of calcium oxalate in this group of plants, probably as Weddellite. The ability to biomineralize SiO2, to produce and accumulate biogenic silica, is suggested now to be a general family trait of the Marattiaceae.Facultad de Ciencias Naturales y Muse
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Caracterização de biominerais por espectroscopia infravermelha em Marattiaceae
2014Co-Authors: Barán, Enrique José, Rolleri, Cristina HildaAbstract:Frond samples of the eusporangiate ferns Marattiaceae genera Angiopteris, Christensenia, Danaea and Marattia were investigated by infrared spectroscopy, under different experimental conditions. The results confirmed the previously reported accumulation of biogenic silica (SiO2) in tissues of these ferns and also showed, for the first time, the presence of calcium oxalate in this group of plants, probably as Weddellite. The ability to biomineralize SiO2, to produce and accumulate biogenic silica, is suggested now to be a general family trait of the Marattiaceae.Laboratorio de Estudios de Anatomía Vegetal Evolutiva y SistemáticaCentro de Química Inorgánic
Christy, Andrew G. - One of the best experts on this subject based on the ideXlab platform.
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The Great Barrier Reef Expedition 1928-29: The crystal structure and occurrence of Weddellite, ideally CaC2O4·2.5H2O, from the Low Isles, Queensland
'Mineralogical Society', 2016Co-Authors: Mills, Stuart J., Christy, Andrew G.Abstract:"Envelope crystals" collected during The Great Barrier Reef Expedition in May 1929 have been studied using low-temperature synchrotron single-crystal X-ray diffraction. The crystals are shown to be Weddellite, with the largest content of zeolitic water reported to date. A new HO site has been located within the crystal structure. Study of the crystals show that the end-member formula for Weddellite should be reported as CaCO·(2.5 - x) HO, where 0 ≤ x ≤ 0.25, instead of CaCO·2HO or CaCO·(2 + x) HO. This is also the first report of Weddellite occurring in a coral reef
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The Great Barrier Reef Expedition 1928–29: The crystal structure and occurrence of Weddellite, ideally CaC₂O₄·2.5H₂O, from the Low Isles, Queensland
Mineralogical Society, 2016Co-Authors: Mills, Stuart J., Christy, Andrew G.Abstract:“Envelope crystals” collected during The Great Barrier Reef Expedition in May 1929 have been studied using low-temperature synchrotron single-crystal X-ray diffraction. The crystals are shown to be Weddellite, with the largest content of zeolitic water reported to date. A new H₂O site has been located within the crystal structure. Study of the crystals show that the end-member formula for Weddellite should be reported as CaC₂O₄·(2.5 – x)H₂O, where 0≤x≤ 0.25, instead of CaC₂O₄·(2H₂O or CaC2O₄·(2 + x )H₂O. This is also the first report of Weddellite occurring in a coral reef
