50,948 research outputs found
Determination of Homo- and Heteronuclear Coupling Constants in Uniformly13C,15N-Labeled DNA Oligonucleotides
No full textA set of experiments to determine homo- and heteronuclear vicinal coupling constants in uniformly C-13-labeled DNA oligonucleotides is presented, 2D and 3D HCCH-E.COSY experiments were used to measure 3J(HH) coupling constants in the deoxyribose ring, a refocused HMBC experiment was used to measure (3)J(CH) coupling constants about the glycosidic torsion angle chi and a P-FIDS-CT-HSQC experiment was used to determine 2J(CP) and 3J(HP) coupling constants about the backbone torsion angle epsilon. The experiments were demonstrated on a uniformly C-13,N-15-labeled 10 base pair (bp) DNA duplex which contains a dA . dT tract 4 bp in length. With these experiments it was possible to extract a number of the coupling constants from duplex DNA
‘Dominant ethnicity’ and the ‘ethnic-civic’ dichotomy in the work of A. D. Smith
No full textThis article considers the way in which the work of Anthony Smith has helped to structure debates surrounding the role of ethnicity in present-day nations. Two major lines of enquiry are evident here. First, the contemporary role of dominant ethnic groups within 'their' nations and second, the interplay between ethnic and civic elements in nationalist argument. The two processes are related, but maintain elements of distinctiveness. Smith's major contribution to the dominant ethnicity debate has been to disembed ethnicity from the ideologically-charged and/or anglo-centric discourse of ethnic relations and to place it in historical context, thereby opening up space for dominant group ethnicity to be considered as a distinct phenomenon. This said, Smith's work does not adequately account for the vicissitudes of dominant ethnicity in the contemporary West. Building on the classical works of Hans Kohn and Friedrich Meinecke, Anthony Smith has also made a seminal contribution to the debate on civic and ethnic forms of national identity and nationalist ideology. As well as freeing this debate from the strong normative overtones which it has often carried, he has continued to insist that the terms civic and ethnic should be treated as an ideal-typical distinction rather than a scheme of classification
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
Extracting Boer-Mulders functions from p+D Drell-Yan processes
No full textWe extract the Boer- Mulders functions of valence and sea quarks in the proton from unpolarized p + D Drell- Yan data measured by the FNAL E866 Collaboration. Using these Boer- Mulders functions, we calculate the cos2 phi asymmetries in unpolarized pp Drell- Yan processes, both for the FNAL E866/ NuSea and the BNL Relativistic Heavy Ion Collider experiments. We also estimate the cos2 phi asymmetries in the unpolarized p (P) over bar Drell- Yan processes at GSI.Astronomy & AstrophysicsPhysics, Particles & FieldsSCI(E)37ARTICLE5null7
Text Mining and Gene Expression Analysis Towards Combined Interpretation of High Throughput Data
No full textMicroarrays can capture gene expression activity for thousands of genes simultaneously and thus make it possible to analyze cell physiology and disease processes on molecular level. The interpretation of microarray gene expression experiments profits from knowledge on the analyzed genes and proteins and the biochemical networks in which they play a role. The trend is towards the development of data analysis methods that integrate diverse data types. Currently, the most comprehensive biomedical knowledge source is a large repository of free text articles. Text mining makes it possible to automatically extract and use information from texts.
This thesis addresses two key aspects, biomedical text mining and gene expression data analysis, with the focus on providing high-quality methods and data that contribute to the development of integrated analysis approaches. The work is structured in three parts. Each part begins by providing the relevant background, and each chapter describes the developed methods as well as applications and results.
Part I deals with biomedical text mining:
Chapter 2 summarizes the relevant background of text mining; it describes text mining fundamentals, important text mining tasks, applications and particularities of text mining in the biomedical domain, and evaluation issues.
In Chapter 3, a method for generating high-quality gene and protein name dictionaries is described. The analysis of the generated dictionaries revealed important properties of individual nomenclatures and the used databases (Fundel and Zimmer, 2006). The dictionaries are publicly available via a Wiki, a web service, and several client applications (Szugat et al., 2005).
In Chapter 4, methods for the dictionary-based recognition of gene and protein names in texts and their mapping onto unique database identifiers are described. These methods make it possible to extract information from texts and to integrate text-derived information with data from other sources. Three named entity identification systems have been set up, two of them building upon the previously existing tool ProMiner (Hanisch et al., 2003). All of them have shown very good performance in the BioCreAtIvE challenges (Fundel et al., 2005a; Hanisch et al., 2005; Fundel and Zimmer, 2007).
In Chapter 5, a new method for relation extraction (Fundel et al., 2007) is presented. It was applied on the largest collection of biomedical literature abstracts, and thus a comprehensive network of human gene and protein relations has been generated. A classification approach (Küffner et al., 2006) can be used to specify relation types further; e. g., as activating, direct physical, or gene regulatory relation.
Part II deals with gene expression data analysis:
Gene expression data needs to be processed so that differentially expressed genes can be identified. Gene expression data processing consists of several sequential steps. Two important steps are normalization, which aims at removing systematic variances between measurements, and quantification of differential expression by p-value and fold change determination. Numerous methods exist for these tasks.
Chapter 6 describes the relevant background of gene expression data analysis; it presents the biological and technical principles of microarrays and gives an overview of the most relevant data processing steps. Finally, it provides a short introduction to osteoarthritis, which is in the focus of the analyzed gene expression data sets.
In Chapter 7, quality criteria for the selection of normalization methods are described, and a method for the identification of differentially expressed genes is proposed, which is appropriate for data with large intensity variances between spots representing the same gene (Fundel et al., 2005b). Furthermore, a system is described that selects an appropriate combination of feature selection method and classifier, and thus identifies genes which lead to good classification results and show consistent behavior in different sample subgroups (Davis et al., 2006).
The analysis of several gene expression data sets dealing with osteoarthritis is described in Chapter 8. This chapter contains the biomedical analysis of relevant disease processes and distinct disease stages (Aigner et al., 2006a), and a comparison of various microarray platforms and osteoarthritis models.
Part III deals with integrated approaches and thus provides the connection between parts I and II:
Chapter 9 gives an overview of different types of integrated data analysis approaches, with a focus on approaches that integrate gene expression data with manually compiled data, large-scale networks, or text mining.
In Chapter 10, a method for the identification of genes which are consistently regulated and have a coherent literature background (Küffner et al., 2005) is described. This method indicates how gene and protein name identification and gene expression data can be integrated to return clusters which contain genes that are relevant for the respective experiment together with literature information that supports interpretation.
Finally, in Chapter 11 ideas on how the described methods can contribute to current research and possible future directions are presented
Instrumentation for measuring the effectiveness of truck spray suppression devices. Final report
No full textReference: Koppa, R. J., Zimmer, R. A., Ivey, D. L., and Pendleton, O. Heavy Truck Splash and Spray Testing. Volume I: Summary. Final Report. College Station, Texas Transportation Insitute, Sept 1984, p. 1-21 - Appendix CNotes: Report covers the period 19 March 1984-31 Aug 1984. Originally dated Aug 1984Texas Transportation Institute, College Stationhttp://deepblue.lib.umich.edu/bitstream/2027.42/184/2/71335a01.0001.001.pd
Verwendung des Sprecherblicks zur syntaktischen Strukturierung beim Sprachverstehen
No full textKreysa H, Knoeferle P. Verwendung des Sprecherblicks zur syntaktischen Strukturierung beim Sprachverstehen. In: Frings C, Mecklinger A, Wentura D, Zimmer HD, eds. Beiträge zur 52. Tagung experimentell arbeitender Psychologen. Lengerich: Pabst Science Publishers; 2010: 165
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
D- and E-criterion for different experimental designs for the Calcium oscillation model.
No full textD- and E-criterion for different experimental designs for the Calcium oscillation model.</p
- …
