Adam vetus tandem laetus novum promat canticum : Adán de San Víctor y la novedad del canto victorino en la lírica mariana medieval

La poesía latina del maestro Adán de San Víctor (ca.11121192), oriundo de Bretaña y canónigo agustino de la abadía parisina de SaintVictor, representa, en su ámbito y en su época, una novedad trascendente dentro de la lírica litúrgica y particularmente de la lírica mariana. La ductilidad rítmica y retórica del subgénero de la sequentia lograda en sus piezas hace de este autor un paradigma de la creación poética litúrgica en la Europa de los siglos XII y XIII. En este sentido, tanto la mención a su obra como la inclusión de sus sequentiae (junto con otras del mismo período y "estilo" gótico) en diversos manuscritos hispánicos, desde las Cantigas de Santa María hasta el ms. Alcobacense 149, permiten considerar la relevante influencia de esta refinada lírica del siglo XII en la confección de poemas y compilaciones marianas del siglo siguiente en la Península Ibérica.

Adam vetus tandem laetus novum promat canticum : Adán de San Víctor y la novedad del canto victorino en la lírica mariana medieval

La poesía latina del maestro Adán de San Víctor (ca.11121192), oriundo de Bretaña y canónigo agustino de la abadía parisina de SaintVictor, representa, en su ámbito y en su época, una novedad trascendente dentro de la lírica litúrgica y particularmente de la lírica mariana. La ductilidad rítmica y retórica del subgénero de la sequentia lograda en sus piezas hace de este autor un paradigma de la creación poética litúrgica en la Europa de los siglos XII y XIII. En este sentido, tanto la mención a su obra como la inclusión de sus sequentiae (junto con otras del mismo período y "estilo" gótico) en diversos manuscritos hispánicos, desde las Cantigas de Santa María hasta el ms. Alcobacense 149, permiten considerar la relevante influencia de esta refinada lírica del siglo XII en la confección de poemas y compilaciones marianas del siglo siguiente en la Península Ibérica.

Adam vetus tandem laetus novum promat canticum : Adán de San Víctor y la novedad del canto victorino en la lírica mariana medieval

La poesía latina del maestro Adán de San Víctor (ca.11121192), oriundo de Bretaña y canónigo agustino de la abadía parisina de SaintVictor, representa, en su ámbito y en su época, una novedad trascendente dentro de la lírica litúrgica y particularmente de la lírica mariana. La ductilidad rítmica y retórica del subgénero de la sequentia lograda en sus piezas hace de este autor un paradigma de la creación poética litúrgica en la Europa de los siglos XII y XIII. En este sentido, tanto la mención a su obra como la inclusión de sus sequentiae (junto con otras del mismo período y "estilo" gótico) en diversos manuscritos hispánicos, desde las Cantigas de Santa María hasta el ms. Alcobacense 149, permiten considerar la relevante influencia de esta refinada lírica del siglo XII en la confección de poemas y compilaciones marianas del siglo siguiente en la Península Ibérica.

TanDEM-X ice thickness dataset for Wilkins Ice Shelf, Antarctic Peninsula, with link to GeoTIFF

The dataset shows the ice thickness over Wilkins Ice Shelf, Antarctic Peninsula derived from TanDEM-X Interferometry. The data has been acquired between June and August 2012. The TanDEM-X heights have been linked to CryoSAT-2 heights (V. Helm) from the respective time stamp. Elevations have been transformed from WGS84 ellipsoidal heights to the EGM2008 geoid. The ice shelf thickness was estimated assuming hydrostatic equilibrium and a mean ice density of 915 kg/m³.

Preceptorium Nider, hoc est, opus preclarissimu[m] ... Iohannis Nider ... in expositionem preceptorum decalogi : diligentissime nunc tandem cum originalibus collatum et recognitum ac multis locis tersum et emendatum.

Hojas imp. por ambas caras

Determination of selected pharmaceutical compounds in biosolids bysupported liquid extraction and gas chromatography?tandem massspectrometry

In this work, an analytical method was developed for the determination of pharmaceutical drugs inbiosolids. Samples were extracted with an acidic mixture of water and acetone (1:2, v/v) and supportedliquid extraction was used for the clean-up of extracts, eluting with ethyl acetate:methanol (90:10, v/v).The compounds were determined by gas chromatography?tandem mass spectrometry using matrix-match calibration after silylation to form their t-butyldimethylsilyl derivatives. This method presentsvarious advantages, such as a fairly simple operation for the analysis of complex matrices, the use ofinexpensive glassware and low solvent volumes. Satisfactory mean recoveries were obtained with thedeveloped method ranging from 70 to 120% with relative standard deviations (RSDs) ? 13%, and limitsof detection between 0.5 and 3.6 ng g?1. The method was then successfully applied to biosolids samplescollected in Madrid and Catalonia (Spain). Eleven of the sixteen target compounds were detected in thestudied samples, at levels up to 1.1 ?g g?1(salicylic acid). Ibuprofen, caffeine, paracetamol and fenofibratewere detected in all of the samples analyzed.

Quantitative high performance liquid chromatography/tandem mass spectrometric analysis of the four classes of F2-isoprostanes in human urine

Isoprostanes (iPs) are free radical catalyzed prostaglandin isomers. Analysis of individual isomers of PGF2α—F2-iPs—in urine has reflected lipid peroxidation in humans. However, up to 64 F2-iPs may be formed, and it is unknown whether coordinate generation, disposition, and excretion of F2-iPs occurs in humans. To address this issue, we developed methods to measure individual members of the four structural classes of F2-iPs, using liquid chromatography/tandem mass spectrometry (LC/MS/MS), in which sample preparation is minimized. Authentic standards of F2-iPs of classes III, IV, V, and VI were used to identify class-specific ions for multiple reaction monitoring. Using iPF2α-VI as a model compound, we demonstrated the reproducibility of the assay in human urine. Urinary levels of all F2-iPs measured were elevated in patients with familial hypercholesterolemia. However, only three of eight F2-iPs were elevated in patients with congestive heart failure, compared with controls. Paired analyses by GC/MS and LC/MS/MS of iPF2α-VI in hypercholesterolemia and of 8,12-iso-iPF2α-VI in congestive heart failure were highly correlated. This approach will permit high throughput analysis of multiple iPs in human disease.

Multiple imprinted sense and antisense transcripts, differential methylation and tandem repeats in a putative imprinting control region upstream of mouse Igf2

The mouse insulin-like growth factor 2 (Igf2) locus is a complex genomic region that produces multiple transcripts from alternative promoters. Expression at this locus is regulated by parental imprinting. However, despite the existence of putative imprinting control elements in the Igf2 upstream region, imprinted transcriptional repression is abolished by null mutations at the linked H19 locus. To clarify the extent to which the Igf2 upstream region contains autonomous imprinting control elements we have performed functional and comparative analyses of the region in the mouse and human. Here we report the existence of multiple, overlapping imprinted (maternally repressed) sense and antisense transcripts that are associated with a tandem repeat in the mouse Igf2 upstream region. Regions flanking the repeat exhibit tissue-specific parental allelic methylation patterns, suggesting the existence of tissue-specific control elements in the upstream region. Studies in H19 null mice indicate that both parental allelic methylation and monoallelic expression of the upstream transcripts depends on an intact H19 gene acting in cis. The homologous region in human IGF2 is structurally conserved, with the significant exception that it does not contain a tandem repeat. Our results support the proposal that tandem repeats act to target methylation to imprinted genetic loci.

Structural characterization of an engineered tandem repeat contrasts the importance of context and sequence in protein folding

To test a different approach to understanding the relationship between the sequence of part of a protein and its conformation in the overall folded structure, the amino acid sequence corresponding to an α-helix of T4 lysozyme was duplicated in tandem. The presence of such a sequence repeat provides the protein with “choices” during folding. The mutant protein folds with almost wild-type stability, is active, and crystallizes in two different space groups, one isomorphous with wild type and the other with two molecules in the asymmetric unit. The fold of the mutant is essentially the same in all cases, showing that the inserted segment has a well-defined structure. More than half of the inserted residues are themselves helical and extend the helix present in the wild-type protein. Participation of additional duplicated residues in this helix would have required major disruption of the parent structure. The results clearly show that the residues within the duplicated sequence tend to maintain a helical conformation even though the packing interactions with the remainder of the protein are different from those of the original helix. It supports the hypothesis that the structures of individual α-helices are determined predominantly by the nature of the amino acids within the helix, rather than the structural environment provided by the rest of the protein.

Automated de novo sequencing of proteins by tandem high-resolution mass spectrometry

A de novo sequencing program for proteins is described that uses tandem MS data from electron capture dissociation and collisionally activated dissociation of electrosprayed protein ions. Computer automation is used to convert the fragment ion mass values derived from these spectra into the most probable protein sequence, without distinguishing Leu/Ile. Minimum human input is necessary for the data reduction and interpretation. No extra chemistry is necessary to distinguish N- and C-terminal fragments in the mass spectra, as this is determined from the electron capture dissociation data. With parts-per-million mass accuracy (now available by using higher field Fourier transform MS instruments), the complete sequences of ubiquitin (8.6 kDa) and melittin (2.8 kDa) were predicted correctly by the program. The data available also provided 91% of the cytochrome c (12.4 kDa) sequence (essentially complete except for the tandem MS-resistant region K13–V20 that contains the cyclic heme). Uncorrected mass values from a 6-T instrument still gave 86% of the sequence for ubiquitin, except for distinguishing Gln/Lys. Extensive sequencing of larger proteins should be possible by applying the algorithm to pieces of ≈10-kDa size, such as products of limited proteolysis.

A knob-associated tandem repeat in maize capable of forming fold-back DNA segments: Are chromosome knobs megatransposons?

A class of tandemly repeated DNA sequences (TR-1) of 350-bp unit length was isolated from the knob DNA of chromosome 9 of Zea mays L. Comparative fluorescence in situ hybridization revealed that TR-1 elements are also present in cytologically detectable knobs on other maize chromosomes in different proportions relative to the previously described 180-bp repeats. At least one knob on chromosome 4 is composed predominantly of the TR-1 repeat. In addition, several small clusters of the TR-1 and 180-bp repeats have been found in different chromosomes, some not located in obvious knob heterochromatin. Variation in restriction fragment fingerprints and copy number of the TR-1 elements was found among maize lines and among maize chromosomes. TR-1 tandem arrays up to 70 kilobases in length can be interspersed with stretches of 180-bp tandem repeat arrays. DNA sequence analysis and restriction mapping of one particular stretch of tandemly arranged TR-1 units indicate that these elements may be organized in the form of fold-back DNA segments. The TR-1 repeat shares two short segments of homology with the 180-bp repeat. The longest of these segments (31 bp; 64% identity) corresponds to the conserved region among 180-bp repeats. The polymorphism and complex structure of knob DNA suggest that, similar to the fold-back DNA-containing giant transposons in Drosophila, maize knob DNA may have some properties of transposable elements.