Dezentralisierung und Partizipation : Chancen und Grenzen lokaler Partizipation im Dezentralisierungsprozess Senegals

Das heutige Westafrika stand von Mitte des 19. Jahrhunderts bis zu Anfang der 1960er Jahre unter vorwiegend französischer und britischer Kolonialherrschaft, welche die vorkolonialen politischen Einheiten zerstörte und der Bevölkerung lange Zeit grundlegende politische und zivile Rechte sowie repräsentative Institutionen vorenthielt (vgl. Gellar 1990: 132). Sie hinterließ den afrikanischen Ländern nach der Unabhängigkeit ein hochgradig zentralisiertes und hierarchisiertes administratives Herrschaftssystem, welches jedoch gleichzeitig dezentrale Elemente integrierte. Es handelte sich um „hierarchisch und raumstrategisch dekonzentrierte, meist zentralörtlich organisierte Verwaltungssysteme“ (Thomi 2001: 24). ... Der Aufbau der Arbeit ist folgender: zunächst werden die verschiedenen strategischen Konzepte der Dezentralisierung erläutert, wobei für die vorliegende Arbeit der Begriff der demokratischen Dezentralisierung (Devolution) entscheidend ist und der Zusammenhang zwischen Dezentralisierung und Demokratisierung herausgearbeitet wird. Diesem folgt eine Definition der zentralen Kategorie dieser Arbeit, dem Begriff der Partizipation. Politische Partizipation soll dabei weiter gefasst werden und nicht nur formal institutionalisierte, sondern auch informelle Formen der Beteiligung einbeziehen. Dieser Ansatz bietet die Möglichkeit, die Partizipation der ländlichen Bevölkerung und besonders der Frauen neu zu definieren. Denn der oft weniger bedeutsamen formellen Partizipation (Wahlbeteiligung, Teilnahme an öffentlichen Versammlungen und schwachen Repräsentation in den Entscheidungsinstanzen) steht ein hohes Maß an Engagement in Basisgruppen gegenüber. Auch wenn es den Selbsthilfegruppen zunächst um die Sicherung der alltäglichen Lebensbedürfnisse geht, bedeutet diese Form der Partizipation einen wichtigen Beitrag zur Konsolidierung der Demokratie. Der Analyse der aktuellen Partizipationschancen im Senegal ist ein kurzer historischer Abriss der Dezentralisierungsreformen seit den 1960er Jahren vorangestellt. Für das Verständnis der heutigen Situation ist es vor allem wichtig zu erkennen, welche Ziele mit den Reformen jeweils verbunden waren. Da die Effektivität von Reformen jedoch von dem ihnen zugrundeliegenden politischökonomischen Kontext abhängt, geht der Beschreibung der Dezentralisierungsmaßnahmen an sich eine Beschreibung der innenpolitischen Entwicklung Senegals mit den spezifischen Merkmalen ihrer politischen Kultur voraus. Meine Annahme ist, dass einige Formen der Partizipation, wie z.B. die Wahlbeteiligung, im Senegal recht positiv bewertet werden können, dass es allerdings strukturelle Hindernisse gibt, die einer weiter reichenden Partizipation im Wege stehen. Der Analyse der elektoralen, direkten und informellen Partizipationsmöglichkeiten, die im Zusammenhang mit den Dezentralisierungsreformen entstanden sind, folgt in einem weiteren Schritt die Untersuchung der Faktoren, die eine erfolgreiche Dezentralisierung und stärkere Partizipation hemmen. Hier sind sowohl auf staatlichinstitutioneller, als auch auf politisch-kultureller Ebene strukturelle Hindernisse zu konstatieren. Chancen zur Partizipation können kaum genutzt werden, wenn die dezentralisierten Strukturen nicht demokratischer Kontrolle unterworfen sind. Daher werden zum Abschluss die institutionelle Leistungserbringung und verschiedene Hebel zur Durchsetzung der Rechenschaftspflicht untersucht

NcDNAlign: Plausible multiple alignments of non-protein-coding genomic sequences

Genome-wide multiple sequence alignments (MSAs) are a necessary prerequisite for an increasingly diverse collection of comparative genomic approaches. Here we present a versatile method that generates high-quality MSAs for non-protein-coding sequences. The NcDNAlign pipeline combines pairwise BLAST alignments to create initial MSAs, which are then locally improved and trimmed. The program is optimized for speed and hence is particulary well-suited to pilot studies. We demonstrate the practical use of NcDNAlign in three case studies: the search for ncRNAs in gammaproteobacteria and the analysis of conserved noncoding DNA in nematodes and teleost fish, in the latter case focusing on the fate of duplicated ultra-conserved regions. Compared to the currently widely used genome-wide alignment program TBA, our program results in a 20- to 30-fold reduction of CPU time necessary to generate gammaproteobacterial alignments. A showcase application of bacterial ncRNA prediction based on alignments of both algorithms results in similar sensitivity, false discovery rates, and up to 100 putatively novel ncRNA structures. Similar findings hold for our application of NcDNAlign to the identification of ultra-conserved regions in nematodes and teleosts. Both approaches yield conserved sequences of unknown function, result in novel evolutionary insights into conservation patterns among these genomes, and manifest the benefits of an efficient and reliable genome-wide alignment package. The software is available under the GNU Public License at http://www.bioinf.uni-leipzig.de/Software/NcDNAlign/

Small ncRNA transcriptome analysis from Aspergillus fumigatus suggests a novel mechanism for regulation of protein synthesis

Small non-protein-coding RNAs (ncRNAs) have systematically been studied in various model organisms from Escherichia coli to Homo sapiens. Here, we analyse the small ncRNA transcriptome from the pathogenic filamentous fungus Aspergillus fumigatus. To that aim, we experimentally screened for ncRNAs, expressed under various growth conditions or during specific developmental stages, by generating a specialized cDNA library from size-selected small RNA species. Our screen revealed 30 novel ncRNA candidates from known ncRNA classes such as small nuclear RNAs (snRNAs) and C/D box-type small nucleolar RNAs (C/D box snoRNAs). Additionally, several candidates for H/ACA box snoRNAs could be predicted by a bioinformatical screen. We also identified 15 candidates for ncRNAs, which could not be assigned to any known ncRNA class. Some of these ncRNA species are developmentally regulated implying a possible novel function in A. fumigatus development. Surprisingly, in addition to full-length tRNAs, we also identified 5′- or 3′-halves of tRNAs, only, which are likely generated by tRNA cleavage within the anti-codon loop. We show that conidiation induces tRNA cleavage resulting in tRNA depletion within conidia. Since conidia represent the resting state of A. fumigatus we propose that conidial tRNA depletion might be a novel mechanism to down-regulate protein synthesis in a filamentous fungus

Computational RNomics of Drosophilids

Recent experimental and computational studies have provided overwhelming evidence for a plethora of diverse transcripts that are unrelated to protein-coding genes. One subclass consists of those RNAs that require distinctive secondary structure motifs to exert their biological function and hence exhibit distinctive patterns of sequence conservation characteristic for positive selection on RNA secondary structure. The deep-sequencing of 12 drosophilid species coordinated by the NHGRI provides an ideal data set of comparative computational approaches to determine those genomic loci that code for evolutionarily conserved RNA motifs. This class of loci includes the majority of the known small ncRNAs as well as structured RNA motifs in mRNAs. We report here on a genome-wide survey using RNAz

SnoReport 2.0 : new features and a refined Support Vector Machine to improve snoRNA identification

Background: snoReport uses RNA secondary structure prediction combined with machine learning as the basis to identify the two main classes of small nucleolar RNAs, the box H/ACA snoRNAs and the box C/D snoRNAs. Here, we present snoReport 2.0, which substantially improves and extends in the original method by: extracting new features for both box C/D and H/ACA box snoRNAs; developing a more sophisticated technique in the SVM training phase with recent data from vertebrate organisms and a careful choice of the SVM parameters C and γ ; and using updated versions of tools and databases used for the construction of the original version of snoReport. To validate the new version and to demonstrate its improved performance, we tested snoReport 2.0 in different organisms. Results: Results of the training and test phases of boxes H/ACA and C/D snoRNAs, in both versions of snoReport, are discussed. Validation on real data was performed to evaluate the predictions of snoReport 2.0. Our program was applied to a set of previously annotated sequences, some of them experimentally confirmed, of humans, nematodes, drosophilids, platypus, chickens and leishmania. We significantly improved the predictions for vertebrates, since the training phase used information of these organisms, but H/ACA box snoRNAs identification was improved for the other ones. Conclusion: We presented snoReport 2.0, to predict H/ACA box and C/D box snoRNAs, an efficient method to find true positives and avoid false positives in vertebrate organisms. H/ACA box snoRNA classifier showed an F-score of 93 % (an improvement of 10 % regarding the previous version), while C/D box snoRNA classifier, an F-Score of 94 % (improvement of 14 %). Besides, both classifiers exhibited performance measures above 90 %. These results show that snoReport 2.0 avoid false positives and false negatives, allowing to predict snoRNAs with high quality. In the validation phase, snoReport 2.0 predicted 67.43 % of vertebrate organisms for both classes. For Nematodes and Drosophilids, 69 % and 76.67 %, for H/ACA box snoRNAs were predicted, respectively, showing that snoReport 2.0 is good to identify snoRNAs in vertebrates and also H/ACA box snoRNAs in invertebrates organisms

The expansion of the metazoan microRNA repertoire

BACKGROUND: MicroRNAs have been identified as crucial regulators in both animals and plants. Here we report on a comprehensive comparative study of all known miRNA families in animals. We expand the MicroRNA Registry 6.0 by more than 1000 new homologs of miRNA precursors whose expression has been verified in at least one species. Using this uniform data basis we analyze their evolutionary history in terms of individual gene phylogenies and in terms of preservation of genomic nearness across species. This allows us to reliably identify microRNA clusters that are derived from a common transcript. RESULTS: We identify three episodes of microRNA innovation that correspond to major developmental innovations: A class of about 20 miRNAs is common to protostomes and deuterostomes and might be related to the advent of bilaterians. A second large wave of innovations maps to the branch leading to the vertebrates. The third significant outburst of miRNA innovation coincides with placental (eutherian) mammals. In addition, we observe the expected expansion of the microRNA inventory due to genome duplications in early vertebrates and in an ancestral teleost. The non-local duplications in the vertebrate ancestor are predated by local (tandem) duplications leading to the formation of about a dozen ancient microRNA clusters. CONCLUSION: Our results suggest that microRNA innovation is an ongoing process. Major expansions of the metazoan miRNA repertoire coincide with the advent of bilaterians, vertebrates, and (placental) mammals

Homology-based annotation of non-coding RNAs in the genomes of Schistosoma mansoni and Schistosoma japonicum

<p>Abstract</p> <p>Background</p> <p>Schistosomes are trematode parasites of the phylum Platyhelminthes. They are considered the most important of the human helminth parasites in terms of morbidity and mortality. Draft genome sequences are now available for <it>Schistosoma mansoni </it>and <it>Schistosoma japonicum</it>. Non-coding RNA (ncRNA) plays a crucial role in gene expression regulation, cellular function and defense, homeostasis, and pathogenesis. The genome-wide annotation of ncRNAs is a non-trivial task unless well-annotated genomes of closely related species are already available.</p> <p>Results</p> <p>A homology search for structured ncRNA in the genome of <it>S. mansoni </it>resulted in 23 types of ncRNAs with conserved primary and secondary structure. Among these, we identified rRNA, snRNA, SL RNA, SRP, tRNAs and RNase P, and also possibly MRP and 7SK RNAs. In addition, we confirmed five miRNAs that have recently been reported in <it>S. japonicum </it>and found two additional homologs of known miRNAs. The tRNA complement of <it>S. mansoni </it>is comparable to that of the free-living planarian <it>Schmidtea mediterranea</it>, although for some amino acids differences of more than a factor of two are observed: Leu, Ser, and His are overrepresented, while Cys, Meth, and Ile are underrepresented in <it>S. mansoni</it>. On the other hand, the number of tRNAs in the genome of <it>S. japonicum </it>is reduced by more than a factor of four. Both schistosomes have a complete set of minor spliceosomal snRNAs. Several ncRNAs that are expected to exist in the <it>S. mansoni </it>genome were not found, among them the telomerase RNA, vault RNAs, and Y RNAs.</p> <p>Conclusion</p> <p>The ncRNA sequences and structures presented here represent the most complete dataset of ncRNA from any lophotrochozoan reported so far. This data set provides an important reference for further analysis of the genomes of schistosomes and indeed eukaryotic genomes at large.</p

Phylogenetic distribution of plant snoRNA families

Background: Small nucleolar RNAs (snoRNAs) are one of the most ancient families amongst non-protein-coding RNAs. They are ubiquitous in Archaea and Eukarya but absent in bacteria. Their main function is to target chemical modifications of ribosomal RNAs. They fall into two classes, box C/D snoRNAs and box H/ACA snoRNAs, which are clearly distinguished by conserved sequence motifs and the type of chemical modification that they govern. Similarly to microRNAs, snoRNAs appear in distinct families of homologs that affect homologous targets. In animals, snoRNAs and their evolution have been studied in much detail. In plants, however, their evolution has attracted comparably little attention. Results: In order to chart the phylogenetic distribution of individual snoRNA families in plants, we applied a sophisticated approach for identifying homologs of known plant snoRNAs across the plant kingdom. In response to the relatively fast evolution of snoRNAs, information on conserved sequence boxes, target sequences, and secondary structure is combined to identify additional snoRNAs. We identified 296 families of snoRNAs in 24 species and traced their evolution throughout the plant kingdom. Many of the plant snoRNA families comprise paralogs. We also found that targets are well-conserved for most snoRNA families. Conclusions: The sequence conservation of snoRNAs is sufficient to establish homologies between phyla. The degree of this conservation tapers off, however, between land plants and algae. Plant snoRNAs are frequently organized in highly conserved spatial clusters. As a resource for further investigations we provide carefully curated and annotated alignments for each snoRNA family under investigation

Multifunctional shade‐tree management in tropical agroforestry landscapes – a review

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87099/1/j.1365-2664.2010.01939.x.pd