Sicherung von Dämmen, Deichen und Stauanlagen : Handbuch für Theorie und Praxis ; Vol. V - 2015

Die Universität Siegen beschäftigt sich seit über 15 Jahren wissenschaftlich und im Bereich der anwendungsorientierten Forschung mit diesem Thema und hat dazu mittlerweile fünf Symposien durchgeführt. Mit der Veröffentlichung soll die langjährige Tradition als etablierte wissenschaftliche Plattform mit einem Wissensaustausch auf europäischer Ebene fortgesetzt werden. Die Bearbeitung dieser Thematik erfolgt auf der Basis der bewährten Kooperation zwischen Geotechnik und Wasserbau an der Universität Siegen. Aktuelle Ereignisse, wie z.B. die aus England oder Australien im Februar des Jahres 2014, machen uns aber auch deutlich, dass ein absoluter Schutz gegen Extremereignisse nicht möglich ist. Sie zeigen aber auch, dass dort wo technischer Hochwasserschutz konsequent umgesetzt wurde Schäden vermieden werden konnten. Wir sind nach den Ereignissen in den vergangenen Jahren aufgefordert wissenschaftlich noch leistungsfähigere und duktilere Systeme zu entwickeln. Weiter ist die Wissenschaft in der Pflicht, die Zivile Sicherheit im Hochwasser-schutz permanent zu bewerten, zu bearbeiten und ganzheitliche-interdisziplinäre und länderübergreifende Lösungen für die Zivilgesellschaft einzufordern

mRNA sequence profile of WT and KO ECs.

<p>(A) Genome-wide differential expression analysis via RNA-sequencing indicates KO ECs differening gene expressions that predominantly effect the extracellular matrix, immune response, wound healing, cell proliferation, cell adhesion and vascular development. (B—E) Overall ontological analysis of both upregulated and downregulated genes between WT and KO ECs. (F) Differential expression of seven genes significant in vascular development was further assessed using qRT-PCR which confirms an increase in Ang-1, MCP-1, and MMP2 in KO RNA transcripts using PCR. *P<0.05; **P<0.01; represented as mean ± SEM.</p

Plantar reperfusion and collateral remodeling post- hindlimb ischemia.

<p>(A) Laser Doppler images of blood flow pre and post ischemia in WT and KO mice. (B) Analysis shows significant increase in plantar blood flow perfusion at 7d post hindlimb ischemia or femoral artery ligation (FAL) in KO mice compared to WT. (C) KO mice also have a significant reduction in toe necrosis compared to WT mice at 7 days post-FAL. (D) The number of CD31-positive arterioles were are in increased in serial sections of both un-injuured and injured adductor muscles in the absence of EC-specific EphA4. (E) Average arteriole diameter in the injured aductor muscle is increased in KO mice compared to WT and KO un-injured tissue at 7d post-FAL. (F-I) Representative high magnification (x20) images from un-injured and injured adductor muscles at 7d post-FAL using CD31 immuno-staining and -fluorescence. Scale bar = 100μm. (J-M) Brightfield images of WT (J and K) and KO (L and M) adductor muscles at 7d post-FAL. *P<0.05; **P<0.01; n = 5-8/group; represented as mean ± SEM. FA = Femoral artery.</p

Vessel Painting and co-labeling of post-natal murine pial vessels.

<p>(A) Inverted VP image of a mouse brain showing selective labeling of the cerebral arteriole network using vessel painting. (B) Identification of pial collaterals using vessel painting (VP, red) and double labeling of with anti-SMA shows, VP does not label SMCs. (C) Confocal image showing cross section a vessel painted pial arteriole, immunotained for SMA, confirming that VP does not label SMCs. (D) Quantification of EphA4 on pial collaterals, represented as mean fluorescence intensity. (E—M) Double labeling of psot-natal day (P)1, P7 and P21 brains using VP (red) and anti-EphA4 (green). EphA4 is expressed on VP-labeled collaterals at P1, P7 and minimally at P21. *P<0.05; n = 5 per group; represented as mean ± SEM.</p

EphA4 EC-specific ablation increases collateral formation in the post-natal murine brain.

<p>(A) KO mice have increased total collaterals in P1, P7, P21 and adult mice. (B) average tortuosity is increased in all KO groups except adult. (C) KO mice have more MCA—ACA collaterals but there is no significant difference in average diameter of collaterals in the mice. (E—H) VP of P1 and adult WT and KO brains. *P<0.05; ***P<0.001; n = 5–9 per group; represented as mean ± SEM.</p

PI3K inhibition attenuates endothelial cell functions following EphA4 ablation.

<p>(A) Western blot analysis indicates increased p-Akt expression in KO ECs compared to WT ECs. Expression is reduced in KO ECs after LY294002 treatment. (B) Densitometric analysis shows a three-fold increase of p-Akt in KO ECs. KO treated with LY294002 have identical p-Akt expression as WT vehicle control. (C—E) In addition treating KO ECs with LY294002 significantly reduced BrdU incorporation, migration and vascular index, respectively. ***P<0.001; n = 16–20 wells/group; represented as mean ± SEM.</p