1,720,968 research outputs found
Detection of a polymorphic 27 bp insertion/deletion in exon 4 of the canine calcitonin/calcitonin gene-related peptide gene I (CALCA)
No full textMolecular analysis and chromosomal assignment of the canine CALC-I/alpha-CGRP gene
No full textWe have isolated a recombinant phage harboring the canine CALC-I/alpha-CGRP gene. The gene spans a region of approx. 5.3 kb and consists of six exons with sizes ranging from 95 bp (exon 2) and 494 bp (exon 4). By alternative splicing, two transcripts with ORFs of 390 and 384 nt are generated. These encode either the 32-amino acid-long hormone calcitonin (CALC or the neurotransmitter calcitonin gene-related peptide (alpha-CGRP) with a length of 37 amino acids after proteolytic processing of precursor molecules. The canine calcitonin precursor consists of 130 amino acids with a molecular mass of 14.05 kDa and a statistical pi of 8.0, whereas the deduced alpha-CGRP precursor harbors 128 amino acids with a molecular mass of 13.87 kDa and a statistical pi of 8.6. Both polypeptides have a common N-terminal region of 76 amino acids that is encoded by exons 2 and 3 and separated by different eight (CALC) or six (alpha-CGRP) amino acid spacers from the biologically active polypeptide. The CALC-I/alpha-CGRP gene is a member of the calcitonin gene family and was assigned to chromosome CFA 16q35.1. A comparative analysis of different dog breeds revealed a breed-specific allelic d(CAGGAG)-hexanucleotide expansion in exon 3. This expansion results in an elongation of the common N-terminal region by two amino acids (glutamine-glutamic acid) and alters the molecular mass to 14.31 kDa (pI 7.9) and 14.13 kDa (pI 8.5) of the calcitonin and alpha-CGRP precursor, respectively
CRIRES spectroscopy and empirical line-by-line identification of FeH molecular absorption in an M dwarf
No full textMolecular FeH provides a large number of sharp and isolated absorption lines that can be
used to measure radial velocity, rotation, or magnetic field strength with high accuracy.
Our aim is to provide an FeH atlas for M-type stars in the spectral region from 986 nm to
1077 nm (Wing-Ford band). To identify these lines in CRIRES spectra of the magnetically
inactive, slowly rotating, M5.5 dwarf GJ1002, we calculated model spectra for the selected
spectral region with theoretical FeH line data. In general this line list agrees with the
observed data, but several individual lines differ significantly in position or in line
strength. After identification of as many as possible FeH lines, we corrected the line
data for position and line strength to provide an accurate atlas of FeH absorption lines
for use in high precision spectroscopy of low mass stars. For all lines, we used a Voigt
function to obtain their positions and equivalent widths. Identification with theoretical
lines was done by hand. For confirmation of the identified lines, we used statistical
methods, cross-correlation techniques, and line intensities. Eventually, we were able to
identify FeH lines from the (0,0), (1,0), (1,1), (2,1), (2,2), (3,2), and (4,3)
vibrational bands in the observed spectra and correct the positions of the lines if
necessary. The deviations between theoretical and observed positions follow a normal
distribution approximately around zero. In order to empirically correct the line strength,
we determined Teff, instrumental broadening (rotational
broadening) and a van der Waals enhancement factor for the FeH lines in GJ1002. We also
give the scaling factors for the Einstein A values to correct the line strengths. With the
identified lines, we derived rotational temperatures from the line intensities for GJ1002.
We conclude that FeH lines can be used for a wide variety of applications in astrophysics.
With the identified lines it will be possible for example to characterize magnetically
sensitive or very temperature sensitive lines, which can be used to investigate M-type
stars
Aligned fractures in carbonate rocks: laboratory and in situ measurements of seismic anisotropy
No full textBy vertical seismic profiling and shear wave analysis we show that a packet of carbonate reservoir rocks, found at nearly 3000 m depth in the North German Basin, is seismically anisotropic. For vertical paths of wave propagation the estimated velocity difference of the split shear waves is 10%. No shear wave birefrigence is observed within the hangingwall which, therefore, has to be regarded as isotropic or transversely isotropic. Additional laboratory investigations of the petrography of drilled carbonate samples and of their seismic velocities show that the anisotropy is most probably caused by subvertical fractures with preferred azimuthal orientation. The strike direction of the aligned fractures determined by analysis of split shear waves is approximately N55 degrees E. This value agrees with recently published directions of maximum horizontal tectonic stress in pre-Zechstein sediments in the eastern part of the North German Basin, but it is in contrast to the world stress map
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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