Integrated transcriptomic and proteomic analyses ofP. falciparumgametocytes: molecular insight into sex-specific processes and translational repression

Sexual differentiation of malaria parasites into gametocytes in the vertebrate host and subsequent gamete fertilization in mosquitoes is essential for the spreading of the disease. The molecular processes orchestrating these transitions are far from fully understood. Here, we report the first transcriptome analysis of male and female Plasmodium falciparum gametocytes coupled with a comprehensive proteome analysis. In male gametocytes there is an enrichment of proteins involved in the formation of flagellated gametes; proteins involved in DNA replication, chromatin organization and axoneme formation. On the other hand, female gametocytes are enriched in proteins required for zygote formation and functions after fertilization; protein-, lipid- and energy-metabolism. Integration of transcriptome and proteome data revealed 512 highly expressed maternal transcripts without corresponding protein expression indicating large scale translational repression in P. falciparum female gametocytes for the first time. Despite a high degree of conservation between Plasmodium species, 260 of these 'repressed transcripts' have not been previously described. Moreover, for some of these genes, protein expression is only reported in oocysts and sporozoites indicating that repressed transcripts can be partitioned into short- and long-term storage. Finally, these data sets provide an essential resource for identification of vaccine/drug targets and for further mechanistic studies

Pipelines under imposed deformation Local buckling

Structural EngineeringCivil Engineering and Geoscience

The B-Formula for the design of fillet welds

Civil Engineering and GeosciencesStructural Engineerin

Constructieve aspecten hoge rekgrens staal S460

Civil Engineering and GeosciencesStructural Engineerin

Hoge rekgrens staal transportleidingen: Deelonderzoek plooien

Civil Engineering and GeosciencesStructural Engineerin

Design rules for fillet welds in Eurocode 3 and AISC

The present design rules for fillet welds in Eurocode 3 lead to very thick fillet welds for higher strength steels S420, S460 and S690. Other design rules, e.g. the AISC specification [6] and the Canadian standard CSA-S16-09 [8] give much smaller fillet weld sizes for these steel grades. Another important difference is that the strength of the filler metal is directly taken into account in the design equation, while in Eurocode 3 Part 1-8 (EN1993-1-8, [3]) the strength of the filler metal is indirectly taken into account. EN1993-1-8 prescribes matching weld metal, while many other codes also allow undermatching weld metal for fillet welds. Allowing undermatching weld metal for fillet welds enables the designer to choose an optimal combination of parent metal, filler metal and welding parameters to comply with the requirements for ductility and strength. A summary is given of previous and present design rules and the results of recent research. Proposals for modification of the Eurocode 3 design rules for fillet welded joints are included, focussing on high strength steel.Structural EngineeringCivil Engineering and Geoscience

Hoge rekgrens staal transportleidingen: Deelonderzoek bezwijken door inwendige druk

Civil Engineering and GeosciencesStructural Engineerin

Toepassing van hoge rekgrens staal voor transportleidingen

Civil Engineering and GeosciencesStructural Engineerin

Accidental actions in steel structures

Part 1-7 of EN 1991 covers accidental actions and gives rules and values for impact loads due to road, train and ship traffic and loads due to internal explosions. In this paper, the application of Part 1-7 of EN 1991 for steel structures is explained. Background information and design strategies are given. Also some application examples are presented. It is shown that often relatively simple measures may provide sufficient robustness to prevent disproportionate damag