Results 1 to 10 of about 311 (137)

Planktonic microbial communities from microbialite-bearing lakes sampled along a salinity-alkalinity gradient. [PDF]

Limnol Oceanogr, 2022
Abstract Continental freshwater systems are particularly vulnerable to environmental variation. Climate change‐induced desertification and the anthropogenic exploitation of hydric resources result in the progressive evaporation and salinization of inland water bodies in many areas of the globe.
Iniesto M, Moreira D, Benzerara K, Reboul G, Bertolino P, Tavera R, López-García P.   +6 more
europepmc   +2 more sources

Micropearls and other intracellular inclusions of amorphous calcium carbonate: an unsuspected biomineralization capacity shared by diverse microorganisms. [PDF]

Environ Microbiol, 2022
Summary An unsuspected biomineralization process, which produces intracellular inclusions of amorphous calcium carbonate (ACC), was recently discovered in unicellular eukaryotes. These mineral inclusions, called micropearls, can be highly enriched with other alkaline‐earth metals (AEM) such as Sr and Ba.
Segovia-Campos I, Martignier A, Filella M, Jaquet JM, Ariztegui D.   +4 more
europepmc   +2 more sources

Untangling the Primary Biotic and Abiotic Controls on Oxygen, Inorganic and Organic Carbon Isotope Signals in Modern Microbialites. [PDF]

Geobiology
ABSTRACT Microbialites are organo‐sedimentary structures formed throughout most of the Earth history, over a wide range of geological contexts, and under a multitude of environmental conditions affecting their composition. The carbon and oxygen isotope records of carbonates, which are most often their main constituents, have been used as a widespread ...
Havas R, Thomazo C, Caumartin J, Iniesto M, Bert H, Jézéquel D, Moreira D, Tavera R, Bettencourt V, López-García P, Vennin E, Benzerara K.   +11 more
europepmc   +2 more sources

Thermochemical Study of 1-Methylhydantoin [PDF]

Molecules, 2022
Using static bomb combustion calorimetry, the combustion energy of 1-methylhydantoin was obtained, from which the standard molar enthalpy of formation of the crystalline phase at T = 298.15 K of the compound studied was calculated.
Juan M. Ledo, Henoc Flores, Fernando Ramos, Elsa A. Camarillo   +3 more
doaj   +2 more sources

Piperidine-Iodine as Efficient Dual Catalyst for the One-Pot, Three-Component Synthesis of Coumarin-3-Carboxamides [PDF]

Molecules, 2022
A simple and efficient one-pot, three-component synthetic method for the preparation of coumarin-3-carboxamides was carried out by the reaction of salicylaldehyde, aliphatic primary/secondary amines, and diethylmalonate.
Manuel Velasco, Nancy Romero-Ceronio, Rosalía Torralba, Oswaldo Hernández Abreu, Miguel A. Vilchis-Reyes, Erika Alarcón-Matus, Erika M. Ramos-Rivera, David M. Aparicio, Jacqueline Jiménez, Eric Aguilar García, David Cruz Cruz, Clarisa Villegas Gómez, Cuauhtémoc Alvarado   +12 more
doaj   +2 more sources

Phenotypic plasticity of life-history traits of a calanoid copepod in a tropical lake: Is the magnitude of thermal plasticity related to thermal variability? [PDF]

PLoS ONE, 2018
According to the Climatic Variability Hypothesis [CVH], thermal plasticity should be wider in organisms from temperate environments, but is unlikely to occur in tropical latitudes where temperature fluctuations are narrow.
Elizabeth Ortega-Mayagoitia, Osvaldo Hernández-Martínez, Jorge Ciros-Pérez   +2 more
doaj   +2 more sources

Alkaline saline lakes: A chemical evolution experiment evaluating the stability of formaldehyde in an aqueous saline environment [PDF]

Heliyon
Formaldehyde condensation in the presence of a mineral catalyst and under alkaline conditions is considered to be a ''messy'' chemical system due to its dependence on the complex chemical equilibrium between the reaction intermediates, which has a ...
Claudio Alejandro Fuentes-Carreón, Adriana Leticia Meléndez-López, Jorge Armando Cruz-Castañeda, Alicia Negrón-Mendoza   +3 more
doaj   +2 more sources

16S rDNA-based analysis reveals cosmopolitan occurrence but limited diversity of two cyanobacterial lineages with contrasted patterns of intracellular carbonate mineralization [PDF]

Frontiers in Microbiology, 2014
Cyanobacteria are mainly thought to induce carbonate precipitation extracellularly via their photosynthetic activity combined with the nucleation potential of exopolymeric substances. The discovery in microbialites of the alkaline lake Alchichica (Mexico)
Marie eRagon, Marie eRagon, Karim eBenzerara, David eMoreira, Rosaluz eTavera, Purificacion eLopez-Garcia   +5 more
doaj   +2 more sources

Reappraising the eruptive history of the Alchichica Maar Volcano (Mexico) based on Sr–Nd isotopes: Understanding the role of the magma source region on the growth of small-volume volcanoes

Solid Earth Sciences
Alchichica Maar is in the eastern sector of the Trans-Mexican Volcanic Belt, where volcanics range from basalts to rhyolites, with 87Sr/86Sr and 143Nd/144Nd values between 0.70293 to 0.70447 (εSr = −21.1 to −4.5) and 0.512733 to 0.512949 (εNd = +3.4 to ...
Jhoanna Silis E, Bodo Weber, Boris Chako-Tchamabe   +2 more
exaly   +3 more sources

Metagenome-based diversity analyses suggest a significant contribution of non-cyanobacterial lineages to carbonate precipitation in modern microbialites [PDF]

Frontiers in Microbiology, 2015
Cyanobacteria are thought to play a key role in carbonate formation due to their metabolic activity, but other organisms carrying out oxygenic photosynthesis (photosynthetic eukaryotes) or other metabolisms (e.g.
Purificacion eLopez-Garcia
doaj   +2 more sources