39 research outputs found

    Miocene winged fruits of Loxopterygium (Anacardiaceae) from the Ecuadorian Andes

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141449/1/ajb21767.pd

    Evolution of the B3 DNA Binding Superfamily: New Insights into REM Family Gene Diversification

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    Background: The B3 DNA binding domain includes five families: auxin response factor (ARF), abscisic acid-insensitive3 (ABI3), high level expression of sugar inducible (HSI), related to ABI3/VP1 (RAV) and reproductive meristem (REM). The release of the complete genomes of the angiosperm eudicots Arabidopsis thaliana and Populus trichocarpa, the monocot Orysa sativa, the bryophyte Physcomitrella patens,the green algae Chlamydomonas reinhardtii and Volvox carteri and the red algae Cyanidioschyzon melorae provided an exceptional opportunity to study the evolution of this superfamily. Methodology: In order to better understand the origin and the diversification of B3 domains in plants, we combined comparative phylogenetic analysis with exon/intron structure and duplication events. In addition, we investigated the conservation and divergence of the B3 domain during the origin and evolution of each family. Conclusions: Our data indicate that showed that the B3 containing genes have undergone extensive duplication events, and that the REM family B3 domain has a highly diverged DNA binding. Our results also indicate that the founding member of the B3 gene family is likely to be similar to the ABI3/HSI genes found in C. reinhardtii and V. carteri. Among the B3 families, ABI3, HSI, RAV and ARF are most structurally conserved, whereas the REM family has experienced a rapid divergence. Thes

    Machiavelli, Lincoln, and the Art of Princely Procrastination

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    This paper examines the phenomenon of procrastination in decision making. In certain circumstances, procrastinating a decision can yield better results in the long term. This paper looks at procrastination and decision making from the point of view of Von Clausewitz and Machiavelli and uses Abraham Lincoln as an example of efficient use of procrastination in decision making. Von Clausewitz looks to find action at the strongest point. The strongest point may not come for some time in the future and thus encourages procrastination. Machiavelli uses procrastination as an offensive capability in decision-making. Through prudence, virtù, and fortune, a prince can use procrastination efficiently and with power. Lincoln procrastinates often in making his decisions. He prefers to have the world move around him rather than to influence events at the earliest opportunity. In this capacity, he operates on a plane higher than his adversaries. Lincoln makes decisions at the time he sees fit. This paper reviews three instances of Lincoln’s successful use of procrastinated decision making in his presidential administration in three scenarios: 1) the sacking of Secretary of War Simon Cameron, 2) the dismissal of General John C. Frémont for insubordination, 3) the manner in which Lincoln handled the Cabinet Crisis of 1862

    Chemical and mineralogical characterization of alpine, sub-alpine, and karst soils, Sava Watershed,

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    Master of ScienceGeologyUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/101684/1/39015069982174.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/101684/2/39015069982174.pd

    Hydrogeochemical characterization and quantification of the groundwater mixture in a hydrogeological basin of the middle zone of San Luis Potosí

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    The hydrogeochemical characterization and water-rock interaction processes in the subbasins of Santa Catarina and Ocampo-Paraíso in the Zona Media of San Luis Potosí have allowed identifying the types of groundwater. The results of the chemical analysis and the regional geological study show the possible rock-water interaction mechanisms. These results indicate that the composition of the groundwater in each of these basins reflects the dissolution of the carbonate and magnesium minerals of the carbonate rocks of Cretaceous age (El Abra Formation), by rainwater, and of the groundwater through a granular medium with a strong influence of the material of volcanic origin. The Ca-HCO3, Ca-Mg-HCO3, water type are modified during the groundwater flow by incorporation of Na+ and SO42- ions. The San Nicolás (subbasin III) has covered by fluvial deposits in a climatic conditions of semiarid regions. The hydrogeochemical analysis of major ions, lithium and bromine allowed identifying that the extracted water from the region is a product of mixing process, involving three endmembers (ternary mixture). The first, Santa Catarina (C1), has the lowest concentrations of bromine and lithium and its recharge occur in the highest altitude land in the region, towards the Sierra de Álvarez. The second end member (C2), displays high values of bromine, low in lithium and originates towards the Ocampo Paraíso Valley. The third end member (C3), has low bromine concentrations, high in lithium, and comes from San Nicolás Tolentino area. The mixing percentages indicate that C1 contributes 50%, C2 gives 31% and C3 adds 19% water to the system. doi: https://doi.org/10.22201/igeof.00167169p.2019.58.4.205

    Morphological and chemical characterization of atmospheric particles PM10 in an urban site in Leon, Guanajuato, Mexico

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    Start PM10 concentrations and their trace metals content (Cd, Co, Cu, Fe and Zn) were determined in an urban site of Leon, Guanajuato during the rainy season 2018. PM10 exceeded the maximum permissible levels established by the Mexican Standards and WHO, constituting a potential risk to population health. Trace metals levels in PM10 were analyzed by Atomic Absorption Spectrometry, and in addition, morphology and elemental content were studied for some selected particles by Scanning Electronic Microscopy and Energy Dispersive Spectrometry. Chemical and morphological characterization revealed that Fe was the more abundant metal (0.986 µg m-3 ), followed in order of importance by Zn (0.243 µg m-3 ), due to theses metals are related to the crustal. Lower concentrations were found for Cu (0.140 µg m-3 ), Cd (0.119 µg m-3 ), Mn (0.070 µg m-3 ) and Co (0.043 µg m-3 ). Meteorological analysis showed that sources located at the SW and NE of the sampling site (industrial parks and facilities related to metals and mineral extraction) influenced the measured concentrations. Enrichment factors showed that all the measured metals were highly influenced by anthropogenic activity. Cancer Risk (CR) and Non-Cancer Risk Coefficients (cardiovascular and respiratory diseases) did not exceed the maximum permissible level established by EPA.The first section in your paper

    Estudio de las deleciones de los genes GSTM1 y GSTT1 y del polimorfismo Ile105Val del gen GSTP1 en pacientes con enfermedad ósea de Paget

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    Fundamento: La enfermedad ósea de Paget (EOP) es un trastorno focal del hueso con aumento el número, tamaño y actividad de los osteoclastos. Algunos datos epidemiológicos apoyan la teoría de su relación con agentes ambientales tóxicos o infecciosos. Su interacción con algunas alteraciones genéticas predisponentes conducirían a la EOP. Las glutatión-S-transferasas (GST) intervienen en la metabolización de toxinas, al catalizar el ataque nucleofílico del sustrato fisiológico, glutatión reducido o GSH (g-Glu-Cys-Gly) sobre el centro electrófilo de un gran número de estructuras tóxicas. Estudiamos si la variabilidad de los genes GSTM1, GSTP1 y GSTT1 se relaciona con el riesgo a desarrollar EOP.Pacientes y métodos: Analizamos a 148 pacientes diagnosticados de EOP y a 207 individuos controles pareados en sexo y edad sin antecedentes de alteraciones óseas. Con DNA genómico obtenido de sangre periférica se estudió la presencia-ausencia de deleción en los genes GSTM1 y GSTT1, mediante PCR multiplex. El estudio del polimorfismo Ile105Val del gen GSTP1 se llevó a cabo mediante PCR y posterior digestión con la enzima de restricción BsmaI. Se analizó la distribución de genotipos mediante el test chi-cuadrado de Pearson. Cuando se encontraron diferencias estadísticamente significativas, realizamos una regresión logística multivariante para conocer el riesgo que puede generar la presencia de un determinado genotipo. Utilizamos el programa SPSS 21.0. Se consideraron diferencias estadísticamente significativas aquéllas con valores de p<0,05. Resultados: Encontramos diferencias en la distribución de la presencia-ausencia de deleción en el gen GSTM1; no ser portador de la deleción o serlo en heterocigosis en el gen GSTM1 confiere un menor riesgo a desarrollar EOP (OR=0,56, IC 95%: 0,36-0,87; p=0,011). En el estudio de los genes GSTT1 y GSTP1 no hubo diferencias significativas. Conclusión: La actividad detoxificadora disminuye cuando se heredan las dos copias delecionadas del gen GSTM1 al disminuir la actividad enzimática; se ha asociado con una mayor susceptibilidad para algunos tumores, hepatopatía alcohólica y otros problemas inflamatorios. No conocemos descripción de su asociación con la EOP. En los individuos portadores del gen GSTM1 delecionado en homocigosis se observa con más frecuencia EOP. Este hecho podría explicar los hallazgos epidemiológicos que asocian la EOP a la exposición a determinados agentes ambientales
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