Youth, Peace and Security: Die Einbeziehung der Jugend in die Sicherheitsagenda der Vereinten Nationen

Junge Menschen spielen eine lang unterschätzte Rolle für Frieden. Das Potenzial ihrer Einbeziehung in die UN-Sicherheitsagenda wurde erstmals 2015 offiziell durch die internationale Gemeinschaft anerkannt. Die UN-Sicherheitsratsresolution 2250 (2015) und Folgeresolutionen 2419 (2018) und 2535 (2020) bilden die Grundlage für die Agenda Jugend, Frieden und Sicherheit (Youth, Peace and Security, YPS). Diese Arbeit leistet einen umfassenden Beitrag zum Verständnis der normativen Grundlagen und Wirkungen der YPS-Agenda. Zunächst werden dafür die drei YPS-Resolutionen ausführlich analysiert. Die daran anschließende rechtliche Würdigung der YPS-Agenda untersucht das Narrativ junger Menschen als Friedensakteur:innen mit Schutzanspruch, eine mögliche Weiterentwicklung des Rechts auf politische Partizipation junger Menschen und inhaltliche Kritik, Chancen sowie Mechanismen der Institutionalisierung der Agenda. Abschließend werden die Auswirkungen der YPS-Agenda auf das UN-System und die UN-Sicherheitsarchitektur untersucht. Die Analyse erkennt die YPS-Agenda als einen Wendepunkt in Bezug auf die Stigmatisierung und den mangelnden Schutz junger Menschen. Die YPS-Resolutionen artikulieren die weitreichende Forderung nach effektiver Jugendpartizipation in Konfliktprävention, -lösung, humanitärer Arbeit, Friedensprozessen und politischen Strukturen und liefern dafür einen umfassenden Werkzeugkasten aus Situationen, Formen und Merkmalen von Beteiligung. Die YPS-Agenda stärkt damit nachhaltige, inklusive Friedensbemühungen und positioniert die Jugend schrittweise, aber dauerhaft in der UN-Sicherheitsagenda.Young people play a long underestimated role for peace. The potential of their inclusion in the UN security agenda was recognized by the international community officially in 2015. UN Security Council Resolution 2250 (2015) and follow-up resolutions 2419 (2018) and 2535 (2020) provide the foundation for the Youth, Peace and Security (YPS) agenda. This paper makes a comprehensive contribution to understanding the normative foundations, effects and implications of the YPS agenda. First, the three YPS resolutions are analyzed in detail. The subsequent legal assessment of the YPS agenda examines the narrative of young people as peace actors with a claim to protection, a possible further development of the right to political participation of young people, as well as content-related criticism, opportunities, and mechanisms of institutionalization of the agenda. Finally, the impact of the YPS agenda on the UN system and its security architecture is examined. The analysis portrays the YPS agenda as a turning point concerning the stigmatization and lack of protection of young people. The YPS resolutions articulate the broad call for effective youth participation in conflict prevention, resolution, humanitarian work, peace processes, and political structures more generally, and provide a comprehensive toolkit of situations, forms, and characteristics of participation for this purpose. The YPS agenda strengthens sustainable, inclusive peace efforts and progressively but permanently positions youth in the UN security agenda

Effects of preharvest, harvest and postharvest factors on the quality of pear (cv. "Rocha") stored under controlled atmosphere conditions

Pears (cv. Rocha’) grown at two locations and picked up at various times during the harvest season were assessed for firmness and colour, following 9 mo of storage under air or under controlled atmosphere conditions. A second-order polynomial was able to accurately fit the effect of time of harvest on pear’s quality, in an essentially empirical modelling effort; the best estimates of the parameters therein depend on the growing location, as well as on the atmosphere gas composition prevailing during storage

Actin filament dynamics are dominated by rapid growth and severing activity in the Arabidopsis cortical array

Metazoan cells harness the power of actin dynamics to create cytoskeletal arrays that stimulate protrusions and drive intracellular organelle movements. In plant cells, the actin cytoskeleton is understood to participate in cell elongation; however, a detailed description and molecular mechanism(s) underpinning filament nucleation, growth, and turnover are lacking. Here, we use variable-angle epifluorescence microscopy (VAEM) to examine the organization and dynamics of the cortical cytoskeleton in growing and nongrowing epidermal cells. One population of filaments in the cortical array, which most likely represent single actin filaments, is randomly oriented and highly dynamic. These filaments grow at rates of 1.7 µm/s, but are generally short-lived. Instead of depolymerization at their ends, actin filaments are disassembled by severing activity. Remodeling of the cortical actin array also features filament buckling and straightening events. These observations indicate a mechanism inconsistent with treadmilling. Instead, cortical actin filament dynamics resemble the stochastic dynamics of an in vitro biomimetic system for actin assembly

Actin filament dynamics are dominated by rapid growth and severing activity in the Arabidopsis cortical array

Metazoan cells harness the power of actin dynamics to create cytoskeletal arrays that stimulate protrusions and drive intracellular organelle movements. In plant cells, the actin cytoskeleton is understood to participate in cell elongation; however, a detailed description and molecular mechanism(s) underpinning filament nucleation, growth, and turnover are lacking. Here, we use variable-angle epifluorescence microscopy (VAEM) to examine the organization and dynamics of the cortical cytoskeleton in growing and nongrowing epidermal cells. One population of filaments in the cortical array, which most likely represent single actin filaments, is randomly oriented and highly dynamic. These filaments grow at rates of 1.7 µm/s, but are generally short-lived. Instead of depolymerization at their ends, actin filaments are disassembled by severing activity. Remodeling of the cortical actin array also features filament buckling and straightening events. These observations indicate a mechanism inconsistent with treadmilling. Instead, cortical actin filament dynamics resemble the stochastic dynamics of an in vitro biomimetic system for actin assembly

Post-transcriptional Gene Silencing Induced by Short Interfering RNAs in Cultured Transgenic Plant Cells

Short interfering RNA (siRNA) is widely used for studying post-transcriptional gene silencing and holds great promise as a tool for both identifying function of novel genes and validating drug targets. Two siRNA fragments (siRNA-a and -b), which were designed against different specific areas of coding region of the same target green fluorescent protein (GFP) gene, were used to silence GFP expression in cultured gfp transgenic cells of rice (Oryza sativa L.; OS), cotton (Gossypium hirsutum L.; GH), Fraser fir [Abies fraseri (Pursh) Poir; AF], and Virginia pine (Pinus virginiana Mill.; PV). Differential gene silencing was observed in the bombarded transgenic cells between two siRNAs, and these results were consistent with the inactivation of GFP confirmed by laser scanning microscopy, Northern blot, and siRNA analysis in tested transgenic cell cultures. These data suggest that siRNA-mediated gene inactivation can be the siRNA specific in different plant species. These results indicate that siRNA is a highly specific tool for targeted gene knockdown and for establishing siRNA-mediated gene silencing, which could be a reliable approach for large-scale screening of gene function and drug target validation

Volatile emissions of scented Alstroemeria genotypes are dominated by terpenes, and a myrcene synthase gene is highly expressed in scented Alstroemeria flowers

Native to South America, Alstroemeria flowers are known for their colourful tepals, and Alstroemeria hybrids are an important cut flower. However, in common with many commercial cut flowers, virtually all the commercial Alstroemeria hybrids are not scented. The cultivar ‘Sweet Laura’ is one of very few scented commercial Alstroemeria hybrids. Characterization of the volatile emission profile of these cut flowers revealed three major terpene compounds: (E)-caryophyllene, humulene (also known as α-caryophyllene), an ocimene-like compound, and several minor peaks, one of which was identified as myrcene. The profile is completely different from that of the parental scented species A. caryophyllaea. Volatile emission peaked at anthesis in both scented genotypes, coincident in cv. ‘Sweet Laura’ with the maximal expression of a putative terpene synthase gene AlstroTPS. This gene was preferentially expressed in floral tissues of both cv. ‘Sweet Laura’ and A. caryophyllaea. Characterization of the AlstroTPS gene structure from cv. ‘Sweet Laura’ placed it as a member of the class III terpene synthases, and the predicted 567 amino acid sequence placed it into the subfamily TPS-b. The conserved sequences R28(R)X8W and D321DXXD are the putative Mg2+-binding sites, and in vitro assay of AlstroTPS expressed in Escherichia coli revealed that the encoded enzyme possesses myrcene synthase activity, consistent with a role for AlstroTPS in scent production in Alstroemeria cv. ‘Sweet Laura’ flowers

Insight on genes affecting tuber development in potato upon <i>Potato spindle tuber viroid</i> (PSTVd) infection

Potato (Solanum tuberosum L) is a natural host of Potato spindle tuber viroid (PSTVd) which can cause characteristic symptoms on developing plants including stunting phenotype and distortion of leaves and tubers. PSTVd is the type species of the family Pospiviroidae, and can replicate in the nucleus and move systemically throughout the plant. It is not well understood how the viroid can affect host genes for successful invasion and which genes show altered expression levels upon infection. Our primary focus in this study is the identification of genes which can affect tuber formation since viroid infection can strongly influence tuber development and especially tuber shape. In this study, we used a large-scale method to identify differentially expressed genes in potato. We have identified defence, stress and sugar metabolism related genes having altered expression levels upon infection. Additionally, hormone pathway related genes showed significant up- or down-regulation. DWARF1/DIMINUTO, Gibberellin 7-oxidase and BEL5 transcripts were identified and validated showing differential expression in viroid infected tissues. Our study suggests that gibberellin and brassinosteroid pathways have a possible role in tuber development upon PSTVd infection

Characterisation of a Desmosterol Reductase Involved in Phytosterol Dealkylation in the Silkworm, Bombyx mori

Most species of invertebrate animals cannot synthesise sterols de novo and many that feed on plants dealkylate phytosterols (mostly C29 and C28) yielding cholesterol (C27). The final step of this dealkylation pathway involves desmosterol reductase (DHCR24)-catalysed reduction of desmosterol to cholesterol. We now report the molecular characterisation in the silkworm, Bombyx mori, of such a desmosterol reductase involved in production of cholesterol from phytosterol, rather than in de novo synthesis of cholesterol. Phylogenomic analysis of putative desmosterol reductases revealed the occurrence of various clades that allowed for the identification of a strong reductase candidate gene in Bombyx mori (BGIBMGA 005735). Following PCR-based cloning of the cDNA (1.6 kb) and its heterologous expression in Saccharomyces cerevisae, the recombinant protein catalysed reduction of desmosterol to cholesterol in an NADH- and FAD- dependent reaction