1,090 research outputs found
A New Early Ripening Table Grape Cultivar Obtained in Pietroasa Research Station: Vitis vinifera L. cv. Mihaela
No full textAbstractThe evolution of the internal Romanian market for table grapes in recent years suggests that there are occasional problems with the supply, sometimes requiring imports, as well as a need for early maturing varieties, which can bring important benefits for both producers and consumers. This paper presents some data regarding a promising new variety of table grapes, Mihaela, obtained at the Pietroasa Research Station located in Buzău county, Romania, by crossing of Vitis vinifera varieties Cardinal and Coarnă neagră, the last being the maternal ancestor. Presented data includes ampelographic features, agrobiological and technological traits for the new Mihaela cultivar, as well as for its parent varieties. The results recorded thus far present Mihaela as a valuable early ripening variety which could be a good addition to the table grapes assortment of many producers
Computational analysis of next generation sequencing data : from transcription start sites in bacteria to human non-coding RNAS
Get PDFThe advent of next generation sequencing (NGS) technologies has revolutionized the field of molecular biology by providing a wealth of sequence data. “Transcriptomics”, which aims to identify and annotate the complete set of RNA molecules transcribed from a genome, is one of the main applications of these high-throughput methods. Special attention has been paid in determining the exact position of the 5’ ends of RNA transcripts, the transcription start sites (TSSs), and subsequently in identifying the regulatory motifs that are ultimately responsible for governing gene expression. Recently, a novel experimental approach termed dRNA-seq has emerged which enables TSS identification in prokaryotic genomes at a genome-wide scale. While the experimental procedure has reached a point of maturity, the computational downstream analysis of dRNA-seq data is still in its infancy. Analysis of dRNA-seq data was previously done manually, a tedious task that is prone to errors and biases. In order to automate this process we developed a computational tool for accurate and systematic analysis of dRNA-seq data to identify the TSSs genome-wide. In particular, we used a Bayesian framework for TSS calling and a Hidden Markov Model to infer the canonical motifs in the promoter regions of TSSs in order to further capture TSSs that show low evidence of expression. In a second contribution, we exploited the power of next generation sequencing to identify and characterize the expression and processing mechanisms of snoRNAs. SnoRNAs are a particular class of non-protein coding RNAs whose main function is post-transcriptional modification of other non-protein coding RNAs. SnoRNAs carry out their function as part of ribonucleoprotein complexes (RNPs). In order to gain insights into these protein-RNA interactions, we used a technique called PAR-CLIP (Photoactivatable-Ribonucleoside-Enhanced Crosslinking and Immunoprecipitation) that allows the identification of protein-RNA contacts at nucleotide resolution. Using PAR-CLIP data, we were able to demonstrate that snoRNAs undergo precise processing and that many loci in the human genome generate snoRNA-like transcripts whose evolutionary conservation and expression are considerably lower than currently catalogued snoRNAs. Finally, we set out to use small RNA-seq data from the ENCODE project to construct a comprehensive catalog of genomic loci that give rise to snoRNAs. In addition we expanded the current catalog of human snoRNAs and studied the plasticity of snoRNA expression across different cell types. Our analysis confirmed prior observations that several snoRNAs show cell type specific expression, mainly in neurons. A more striking observation was that snoRNA expression appears to be strongly dysregulated in cancers which could lead to the identification of novel biomarkers
Mihaela Koletnik, Slovenskogoriško narečje (Maribor 2001)
No full textThe article brings a presentation of a monograph Slovenskogoriško narečje (The Slovenske Gorice Dialect) by Mihaela Koletnik, a dialectologist from Maribor. This is the 12th publication from the Zora series issued by Slavistično društvo Maribor. The results of author š years-long research on the phonological, morphological and syntactic levels of the Pannonian Slovenske Gorice dialect are presented in this monograph. The author justifies the division of the dialect into two sub-dialects on the basis of the quantitative opposition between the permanently long vowels on the one hand, and the old and the new acute vowels on the other.V članku je predstavljena monografija mariborske dia-lektologinje Mihaele Koletnik Slovenskogoriško narečje, kije kot 12. knjiga iz zbirke Zora izšla pri Slavističnem društvu Maribor. V njej avtorica predstavlja rezultate svojega večletnega raziskovanja gla-soslovne, oblikoslovne in skladenjske ravnine panonskega slovensko-goriškega narečja ter utemeljuje njegovo delitev na dve podnarečji, na vzhodno in zahodno na podlagi kolikostnega nasprotja med stalno dolgimi ter staro- in novoakutiranimi samoglasniki
Mihaela Koletnik, Panonsko lončarsko in kmetijsko izrazje ter druge dialektološke razprave: Maribor: Filozofska fakulteta, Mednarodna založba Oddelka za slovanske jezike in književnosti (Zora 60), 2008, 258 str.
Get PDFThe author presents a monograph by the linguist Mihaela Koletnik and assesses it as a valuable enrichment of Slovenian dialectological lexicology.Avtorica predstavlja monografijo jezikoslovke dr. Mihaele Koletnik, Panonsko lončarsko in kmetijsko izrazje ter druge dialektološke razprave, jo ocenjuje kot dragoceno obogatitev slovenske dialektološke leksikologije
Regulation of gene expression by micrornas : targeting specificity, kinetics and function
Get PDFSummary: Understanding gene regulation is a central question of molecular biology. For decades, gene expression was thought to be controlled by a complex network of proteins called transcription factors. But ten years ago, microRNAs (miRNAs), a distinct class of short, evolutionarily-conserved non-coding RNAs were found to regulate gene expression. Hundreds of miRNAs have since then been discovered in species ranging from plants to nematodes to mammals, where they regulate diverse biological processes such as development, metabolism, immunity, cell cycle. MicroRNAs load into the Argonaute protein of the RNA-Induced Silencing Complex (RISC) and provide binding specificity to it. Upon guiding the RISC to a complementary motif in the 3' untranslated transcribed region (UTR) of a mRNA, miRNAs inhibit the translation and increase the decay rate of the target mRNA.
While the molecular machinery required for miRNA action is well characterized, the biological function of the miRNAs identified so far remains unknown. Neither do we know through what target genes miRNAs achieve their biological function. The most common approach to this question consists in identifying genes that are differentially expressed following the experimental perturbation of the expression of a given miRNA by means of genetic knock-out or transfection. Perturbing the expression of a single miRNA has important side-effects on gene expression, but this problem can be partly addressed by crossing the genes responding to the miRNA perturbation with computational miRNA target predictions. In this thesis, we first illustrate how such a combined experimental and computational approach can be used to understand how the miR-375 miRNA controls glucose homeostasis.
However, in practice, extracting direct, functional miRNA targets from miRNA perturbation experiments and computational predictions is a difficult task because state-of-the-art computational predictions yield large amounts of false-positives. We therefore set to improve the accuracy of computational predictions by inferring what sequence and structure properties characterize functional miRNA binding sites in a large number of miRNA perturbation experiments. We then combined these properties into an algorithm that is most accurate at miRNA target prediction. Also, we show that miRNA binding sites carried by mRNAs that respond to miRNA perturbation share the same properties as miRNA binding sites that are under evolutionary selective pressure, suggesting that miRNA binding sites may have been shaped by evolution to favor mRNA degradation. Further analyses also lead to the view that the temporal aspects of miRNA regulation may be far more important to the miRNA target identification problem than previously thought, especially for experiments measuring the effects of miRNA perturbation at the protein level, where taking the temporal aspects of miRNA regulation into account appears necessary both during experimental design and subsequent data analysis.
While measurements from combined miRNA perturbation experiments and omics assays are crucial to determining what genes are regulated by a given miRNA, they are contaminated by side-effects and do not provide information on the precise location of the miRNA binding site within the 3' UTR of the target genes. To address these problems, we introduce PAR-CLIP, a combination of biochemical and computational methods to identify miRNA binding sites in high-throughput. The mRNA-miRNA-Argonaute ternary complex are first cross-linked. The ternary complex is then immuno-precipitated and the unprotected RNA eliminated by enzymatic digestion. Finally, ultra high-throughput sequencing of the remaining RNA and computational processing of the resulting sequencing libraries reveals the precise mRNA regions bound by miRNAs. PAR-CLIP does not require miRNA perturbation and makes it possible to identify thousands of miRNA binding sites in one experiment, with nucleotide resolution.
In summary, the present thesis establishes methods that make it possible to map miRNA-mRNA interactions with high accuracy in the spatial domain, and paves the way for future investigation of miRNA-mediated gene regulation in the temporal domain. These methods will be useful in understanding the miRNA-mRNA interactions underlying the implication of miRNAs in the regulation of biological processes.
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Zusammenfassung: Die Regulation der Genexpression ist eine zentrale Frage der molekularen Biologie. Während Jahrzehnten wurde angenommen, dass die Expression der Genen von komplexen Netzwerken kontrolliert wird, die aus Proteinen, so genannten Transkriptionsfaktoren bestehen. Vor zehn Jahren wurde entdeckt, dass microRNAs (miRNAs) eine eigene Klasse kleiner, in der Evolution konservierter, nicht-codierender RNA bilden, die Genexpression regulieren. Seitdem wurden hunderte von miRNAs in Organismen, unter ihnen Pflanzen, Nematoden und Säugetieren entdeckt, wo sie diverse biologische Prozesse wie Entwicklung, Metabolismus, Immunität, Zellzyklus regulieren. MicroRNAs binden an die Argonaute Protein vom RNA-Induced Silencing Complex (RISC) und bestimmen so die Bindungsspezifität der Argonaute. MiRNAs führen dann den RISC zu einem komplementären Motif der 3' untranslatierten Region (UTR) einer mRNA, was zur Inhibition der Translation und zur Erhöhung der Zerfallsrate der gebundenen mRNA führt.
Während die molekularen Mechanismen der Genexpressionsregulation durch miRNAs identifiziert wurden, bleibt die biologische Funktion einer grossen Mehrheit der miRNAs, die so weit entdeckt wurden, unbekannt. Es ist zudem unklar, durch welche Gene die miRNA ihre Funktion ausüben. Die häufigste Herangehensweise, diese Frage zu beantworten ist die Identifikation von Genen, deren Expression durch eine gegebene miRNA gestört wird. Genetische Knock-Outs oder Transfektionen sind experimentelle Mittel um die Expression zu stören. Die Expression einer einzelnen miRNAs zu stören kann erhebliche sekundäre Effekte auf die Expression von Genen haben. Durch die Kreuzung von miRNA abhängigen, differentiel exprimierten Genen mit rechnergeschützten miRNA Bindundungsstellenvorhersagen (rmBV) kann dieses Problem teilweise gelöst werden. In dieser Dissertation wurde diese Strategie eingesetzt um zu untersuchen, wie miRNA-375 die Glukosehomeostase kontrolliert.
In der Praxis ist es jedoch eine anspruchsvolle Arbeit, direkte, funktionelle miRNA Zielgene aus miRNA-Störungsexperimenten und rmBV zu extrahieren da rmBV in der Regel einen hohen Anteil an falsch Positiven liefern. Wir verbesserten die Genauigkeit der rmBV indem wir die Sequenz- und Struktureigenschaften von funktionellen miRNA Bindungsstellen aus einer grossen Anzahl von miRNA Störungsexperimenten charakterisierten. Die identifizierten Eigenschaften wurden dann mit dem Algorithmus zur Vorhersage der miRNA-Bindungsstellen kombiniert, der bei der Identifikation von Ziel-miRNA am genauesten ist. Zudem zeigen wir, dass miRNA Bindungsstellen von miRNA-abhängigen mRNAs dieselben Eigenschaften aufweisen wie Bindungsstellen, welche unter evolutionärem Selektionsdruck stehen. Das führt zur Hypothese, dass miRNA Bindungsstellen durch die Evolution umgeformt wurden, um den mRNA Zerfall zu bevorzugen. Weitere Analysen führten zur Auffassung, dass die zeitlichen Aspekte der miRNA Regulation viel wichtiger sein könnten als bisher angenommen. Dies speziell für Experimente, die den Effekt der miRNA Störung auf der Ebene der Proteine messen. Bei diesen Experimenten scheint es unentbehrlich zu sein, während der Planung und Datenanalyse Rücksicht auf die zeitlichen Aspekte der miRNA Regulation zu nehmen.
Messungen aus kombinierten miRNA Störungsexperimenten und Omics-Versuchen sind ausschlaggebend um festzustellen welche Gene von einer bestimmten miRNA reguliert werden. Sie leiden jedoch darunter, dass sie von sekundären Effekten gestört werden und dass sie keine Information über die genaue Lokalisation der miRNA Bindungsstellen liefern. Um diese Probleme zu lösen wurde die PAR-CLIP Methode entwickelt. Dies ist eine Kombination aus biochemischen und rechnergestützten Methoden um miRNA Bindungsstellen in hohen Datendurchsätzen zu identifizieren. Die ternären mRNA-miRNA-Argonaute Komplexe werden erst kovalent gebunden, dann immuno-prezipitiert. Danach wird die ungeschützte RNA in einem enzymatischen Verdau eliminiert. Schlussendlich wird die verbleibende RNA sequenziert und durch rechnergestützte Verarbeitung der Sequenzierdaten wird festgestellt, welche spezifischen mRNA Regionen von miRNAs gebunden werden. PAR-CLIP benötigt keine miRNA Störung und ermöglicht die Identifizierung tausender miRNA Bindungsstellen Nukleotid-Auflösend in einem einzigen Versuch.
Zusammengefasst führt diese Dissertation Methoden ein, mit denen sich miRNA-mRNA Wechselwirkungen mit hoher räumlicher Genauigkeit kartografisieren lassen. Zudem öffnet sie den Weg für zukünftige Untersuchungen von zeitlichen Domänen in der miRNA vermittelten Genregulation. Diese Methoden werden entscheidend zum Verständnis der miRNA-mRNA Wechselwirkungen beitragen und den Einfluss der miRNA in der Regulation biologischer Prozesse betonen
Representations and Consequences of Moral Evil in Cenușă rece by Mihaela Perciun
Get PDFThis article offers a literary analysis of the existential dilemmas and psychological traumas of the characters in Mihaela Perciun’s novel, Cenușă rece. The sources and the chain of causality that marked the destinies of the characters from the perspective of moral evil are particularly highlighted. We have shown that moral deviations and the constraint of freedom of conscience are what can create both social dissensions and identity fractures over time. By using black humor, the author illustrates an upside-down world, wicked and with values followed only on a declarative level, thus managing to offer us a full picture of this society. It also analyzes the drama of three generations of women and how the male character, Tudor Cocargea, marked their existence by one moral slip he committed. Thus, we found that the characters, although they are blood relatives, are devoid of affection and totally unknown to each other
Mihaela Ursa, Indisciplina ficțiunii: Viața de după carte a literaturii, Cluj-Napoca: Casa Cărții de Știință, 2022, 312 p.
Get PDFIn an increasingly apocalyptic climate in which the death of literature is loudly proclaimed, Mihaela Ursa refuses a nostalgic and melancholic reflection on the decline of the culture of the book. Instead, she chooses to investigate the ways in which the current media landscape has shaped the reception of fiction and how these mutations can be used in order to “revive” the classics and literature in general for a new generation of digital natives. Therefore, although this book is focused on canonical texts, the author does not intend to discuss their canonicity or their aesthetic value, but the way in which they are reappropriated through their transmedial circulation. The introductory chapter starts with the important assertion that literature is no longer the privileged road towards accessing narratives. However, instead of either mourning or praising the end of the literature-centric era, the author proposes a more useful activity: reflecting on how this change may impact our relationship with fiction. Since cultural and artistic revolutions do not manifest themselves as a destruction of previous practices in their field, the new technologies and media that are developing very rapidly do not signify the end of the book as a material support or the end of literacy as an ability, but instead their mutation and integration in a new network of narrative media. After all, as Mihaela Ursa argues, transmediality has been a trait of artistic productions since the very beginning, the rise of literature being the phenomenon actually responsible for narrowing the narrative space to its strictly written manifestation
Mihaela Ursa, Indisciplina ficțiunii: Viața de după carte a literaturii, Cluj-Napoca: Casa Cărții de Știință, 2022, 312 p.
Get PDFIn an increasingly apocalyptic climate in which the death of literature is loudly proclaimed, Mihaela Ursa refuses a nostalgic and melancholic reflection on the decline of the culture of the book. Instead, she chooses to investigate the ways in which the current media landscape has shaped the reception of fiction and how these mutations can be used in order to “revive” the classics and literature in general for a new generation of digital natives. Therefore, although this book is focused on canonical texts, the author does not intend to discuss their canonicity or their aesthetic value, but the way in which they are reappropriated through their transmedial circulation. The introductory chapter starts with the important assertion that literature is no longer the privileged road towards accessing narratives. However, instead of either mourning or praising the end of the literature-centric era, the author proposes a more useful activity: reflecting on how this change may impact our relationship with fiction. Since cultural and artistic revolutions do not manifest themselves as a destruction of previous practices in their field, the new technologies and media that are developing very rapidly do not signify the end of the book as a material support or the end of literacy as an ability, but instead their mutation and integration in a new network of narrative media. After all, as Mihaela Ursa argues, transmediality has been a trait of artistic productions since the very beginning, the rise of literature being the phenomenon actually responsible for narrowing the narrative space to its strictly written manifestation
Philopterus hispaniolensis Fedorenko 1987
No full text<i>Philopterus hispaniolensis</i> Fedorenko, 1987 <p> <b>Report:</b> [1] Touleshkov (1964a); [2] Ilieva (2005).</p> <p> <b>Host:</b> <i>Passer hispaniolensis</i> (Temminck) [1, 2].</p> <p> <b>Distribution in Bulgaria:</b> Pazardzhik, Harmanli [1]; Nova Cherna (Silistra Region) [2].</p> <p> <b>Remarks:</b> Touleshkov (1964a) identified the species as <i>Philopterus fringillae</i> (Scopoli, 1772). The corresponding material was examined and re-identified as <i>Philopterus hispaniolensis</i> Fedorenko, 1987 by the present author.</p>Published as part of <i>Ilieva, Mihaela, 2009, Checklist of the chewing lice (Insecta: Phthiraptera) from wild birds in Bulgaria, pp. 1-66 in Zootaxa 2138 (1)</i> on page 37, DOI: 10.11646/zootaxa.2138.1.1, <a href="http://zenodo.org/record/5314302">http://zenodo.org/record/5314302</a>
Spodnjesavinjska dolina v vizitacijskih zapisnikih goriškega nadškofa Karla Mihaela grofa Attemsa
Get PDFDrawing on the visitation minutes of the first Archbishop of Gorizia, Karl Michael von Attems, the author of the article aims to present the ecclesiastical conditions in the Lower Savinja Valley during the second half of the eighteenth century. Apart from the archbishop, visitations were also conducted by his various substitutes (delegates), the Celje city parish priest and Archdeacon Dr. Martin Sumpichler, as well as Rudolf Joseph von Edling, Auxiliary Bishop of Gorizia. The visitations were carried out with a view to assessing the ecclesiastical conditions across parishes, visiting numerous castle chapels and poorhouses, consecrating churches, granting various levels of clerical ordinations to both diocesan and monastic candidates for the priesthood, as well as settling various administrative affairs.Prispevek poskuša na podlagi vizitacijskih zapisnikov prvega goriškega nadškofa Karla Mihaela grofa Attemsa prikazati cerkvene razmere v Spodnjesavinjski dolini v drugi polovici 18. stoletja. Poleg njega so vizitacije opravljali še različni namestniki, npr. celjski mestni župnik in arhidiakon dr. Martin Sumpichler ter goriški pomožni škof Rudolf Jožef grof Edling. Ob tej priložnosti so bile pregledane cerkvene razmere po župnijah, obiskane so bile številne grajske kapele in špitali, posvečena je bila vrsta cerkva, podeljene so bile različne stopnje kleriških redov (nižjih in višjih) tako škofijskim kot tudi redovnim kandidatom za duhovniški poklic, urejale pa so se tudi različne administrativne zadeve
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