ΜΕΤΡΗΣΕΙΣ ΤΥΡΒΩΔΟΥΣ ΡΟΗΣ ΣΕ ΑΝΟΙΚΤΟ ΑΓΩΓΟ ΔΙΑΠΕΡΑΤΟΥ ΠΥΘΜΕΝΑ ΜΕ ΑΝΕΜΟΜΕΤΡΙΑ ΘΕΡΜΟΥ ΦΙΛΜ

Στην  εργασία  αυτή  διερευνάται  εργαστηριακά  η  τυρβώδης  ροή  σε ανοικτό  αγωγό  με  διαπερατό  πυθμένα  με  τη  χρήση  ανεμομετρίας  θερμού  φιλμ (hot-film). Ο διαπερατός πυθμένας  προσομοιώνεται με πορώδη φίλτρα πορώδους ε  ίσου με 0.70  και 0.91.  Το  σχετικό  πάχος  πορώδους s΄/h (s΄=πάχος  πορώδους, h=συνολικό βάθος ροής πάνω και μέσα από το πορώδες στρώμα) μεταβάλλεται από 0.375 έως 0.5. Μετρήσεις  της  παροχής,  μέσης  ταχύτητας  και  τυρβωδών  μεγεθών (ένταση  τύρβης, τάσεις Reynolds) φανερώνουν την επίδραση των παραπάνω μεγεθών (ε και s΄/h)  στα χαρακτηριστικά της ροής και στην παροχετευτική ικανότητα του αγωγού.Turbulent flow in an open channel with a permeable bed is investigated experimentally with the use of hot-film anemometry. The permeable bed is simulated with porous filters of porosity  ε equal to 0.70 and 0.91. The relative thickness of the porous layer s΄/h (s΄=porous thickness, h=total flow depth over and through porous layer) varies between 0.375 and 0.5. Measurements of discharge, mean velocity and turbulence characteristics (turbulence intensity, Reynolds stresses) indicate the effect of ε and s΄/h on the flow characteristics and the discharge capacity of the channel.

SASICE: Safety and sustainability in civil engineering

The performance of the built environment and the construction sector are of major importance in Europe’s long term goals of sustainable development in a changing climate. At the same time, the quality of life of all European citizens needs to be improved and the safety of the built environment with respect to man-made and natural hazards, such as flooding and earthquakes, needs to be ensured. Education has a central role to play in the transformation of a construction sector required to meet increasing demands with regard to safety and sustainability. In this work, the SASICE project is presented. The aim of this project is to promote the integration of safety and sustainability in civil engineering education. The project is organised in the context of the Lifelong Learning Programme, funded by the European Community. The coordinator organisation is the University of Bologna. Nine partner universities from different countries are involved in this transnational project. The universities participating to the project constitute a network of high level competences in the civil engineering area, with several opportunities to improve lifelong learning adopting different media: joint curricula, teaching modules and professor and student exchanges. As a response to the challenge regarding new educational methods in sustainable engineering, teaching modules are developed in 4 thematic areas: (1) Safety in construction, (2) Risk induced by Natural Hazards Assessment, (3) Sustainability in construction, and (4) Sustainability at the territorial level. The development of the teaching modules is based on an extensive analysis of the need for highly qualified education on Safety and Sustainability involving all relevant stakeholders (European and national authorities, companies, research institutes, professional organizations, and universities).The main target is enabling students to introduce these advanced topics in their study plans and curricula and reach, at the end of their studies, a specific skill and expertise in safety and sustainability in Civil Engineering. With our natural resources fading away and our infrastructure in dire need of repair, new trends and challenges in civil engineering education in the concept of “Sustainable Development” are needed to be adressed.<br/

Wave propagation over posidonia oceanica: large scale experiments

Posidonia oceanica meadows are considered to be of high importance to the environmental conservation in the Mediterranean Sea, supporting a highly biodiverse habitat and protecting from coastal erosion. In the CIEM wave flume of LIM/UPC (Barcelona, Spain) large scale experiments have been conducted for measuring wave attenuation, transmission and energy dissipation over artificial P. oceanica in intermediate and shallow waters. The effects of submergence ratio hs/D (hs = height of seagrass, D = water depth) and seagrass density (number of stems per squared meter) on the above characteristics are investigated. Mean velocities above and within the simulated P. oceanica are measured and the wave induced flow within the seagrass, which influences processes such as nutrient uptake, waste removal and larval dispersion, is estimated. A meadow with a total length of 10.70 m was constructed using polypropylene artificial plants. Measurements of wave height at different locations along the meadow indicate attenuation of waves for three different submergence ratios (hs/D), two seagrass densities (stems/m2) and various wave conditions. Results are also analysed with regard to the wave induced flow within the field and the effects of hs/D and seagrass density on mean flow characteristics are investigated based on measurements of mean velocities taken within the meadow.Peer ReviewedPostprint (published version

Illumination of understudied ciliary kinases

Cilia are cellular signaling hubs. Given that human kinases are central regulators of signaling, it is not surprising that kinases are key players in cilia biology. In fact, many kinases modulate ciliogenesis, which is the generation of cilia, and distinct ciliary pathways. Several of these kinases are understudied with few publications dedicated to the interrogation of their function. Recent efforts to develop chemical probes for members of the cyclin-dependent kinase like (CDKL), never in mitosis gene A (NIMA) related kinase (NEK), and tau tubulin kinase (TTBK) families either have delivered or are working toward delivery of high-quality chemical tools to characterize the roles that specific kinases play in ciliary processes. A better understanding of ciliary kinases may shed light on whether modulation of these targets will slow or halt disease onset or progression. For example, both understudied human kinases and some that are more well-studied play important ciliary roles in neurons and have been implicated in neurodevelopmental, neurodegenerative, and other neurological diseases. Similarly, subsets of human ciliary kinases are associated with cancer and oncological pathways. Finally, a group of genetic disorders characterized by defects in cilia called ciliopathies have associated gene mutations that impact kinase activity and function. This review highlights both progress related to the understanding of ciliary kinases as well as in chemical inhibitor development for a subset of these kinases. We emphasize known roles of ciliary kinases in diseases of the brain and malignancies and focus on a subset of poorly characterized kinases that regulate ciliary biology

Effect of the G375C and G346E Achondroplasia Mutations on FGFR3 Activation

Two mutations in FGFR3, G380R and G375C are known to cause achondroplasia, the most common form of human dwarfism. The G380R mutation accounts for 98% of the achondroplasia cases, and thus has been studied extensively. Here we study the effect of the G375C mutation on the phosphorylation and the cross-linking propensity of full-length FGFR3 in HEK 293 cells, and we compare the results to previously published results for the G380R mutant. We observe identical behavior of the two achondroplasia mutants in these experiments, a finding which supports a direct link between the severity of dwarfism phenotypes and the level and mechanism of FGFR3 over-activation. The mutations do not increase the cross-linking propensity of FGFR3, contrary to previous expectations that the achondroplasia mutations stabilize the FGFR3 dimers. Instead, the phosphorylation efficiency within un-liganded FGFR3 dimers is increased, and this increase is likely the underlying cause for pathogenesis in achondroplasia. We further investigate the G346E mutation, which has been reported to cause achondroplasia in one case. We find that this mutation does not increase FGFR3 phosphorylation and decreases FGFR3 cross-linking propensity, a finding which raises questions whether this mutation is indeed a genetic cause for human dwarfism

Fate mapping of human glioblastoma reveals an invariant stem cell hierarchy

Human glioblastomas (GBMs) harbour a subpopulation of glioblastoma stem cells (GSCs) that drive tumourigenesis. However, the origin of intra-tumoural functional heterogeneity between GBM cells remains poorly understood. Here we study the clonal evolution of barcoded GBM cells in an unbiased way following serial xenotransplantation to define their individual fate behaviours. Independent of an evolving mutational signature, we show that the growth of GBM clones in vivo is consistent with a remarkably neutral process involving a conserved proliferative hierarchy rooted in GSCs. In this model, slow-cycling stem-like cells give rise to a more rapidly cycling progenitor population with extensive self-maintenance capacity, that in turn generates non-proliferative cells. We also identify rare “outlier” clones that deviate from these dynamics, and further show that chemotherapy facilitates the expansion of pre-existing drug-resistant GSCs. Finally, we show that functionally distinct GSCs can be separately targeted using epigenetic compounds, suggesting new avenues for GBM targeted therapy.This study was supported by the Canadian Institutes of Health Research (funding reference number 142434), the Ontario Institute for Cancer Research through funding provided by the Government of Ontario, and Stand Up To Cancer (SU2C) Canada. P.B.D. is also supported by the Terry Fox Research Institute, the Canadian Cancer Society, the Hospital for Sick Children Foundation, Jessica’s Footprint Foundation, the Hopeful Minds Foundation, the Bresler family, and B.R.A.I.N. Child. P.B.D. holds a Garron Family Chair in Childhood Cancer Research at The Hospital for Sick Children. B.D.S. acknowledges the support of the Wellcome Trust (grant number 098357/Z/12/Z). C.J.E. acknowledges grant support from the Canadian Cancer Society and the Terry Fox Run. Research was supported by SU2C Canada Cancer Stem Cell Dream Team Research Funding (SU2C-AACR-DT-19-15) provided by the Government of Canada through Genome Canada and the Canadian Institutes of Health Research, with supplementary support from the Ontario Institute for Cancer Research through funding provided by the Government of Ontario. Stand Up To Cancer Canada is a program of the Entertainment Industry Foundation Canada. Research funding is administered by the American Association for Cancer Research International – Canada, the scientific partner of SU2C Canada. The Structural Genomics Consortium is funded by AbbVie, Bayer, Boehringer Ingelheim, GSK, Genome Canada, Ontario Genomics Institute, Janssen, Lilly, Merck, Novartis, the government of Ontario, Pfizer, Takeda, and the Wellcome Trust

Review of flood hazard mapping

This is the final version of a report on review on flood hazard mapping.Floodsit

MEASUREMENT OF DISCHARGE WITH PERMEABLE BROAD-CRESTED WEIRS

Σε πολλές περιπτώσεις η μέτρηση της παροχής σε ποταμούς και χείμαρρους γίνεται με τη χρήση αδιαπέρατων εκχειλιστών παχιάς στέψης. Στην παρούσα εργασία μελετώνται διαπερατοί εκχειλιστές οι οποίοι θεωρούνται περισσότερο φιλικοί προς το περιβάλλον. Για το λόγο αυτό χρησιμοποιούνται εκχειλιστές διαφορετικού πορώδους (n=0.42 και n=0.55) και η παροχετευτική τους ικανότητα συγκρίνεται με αυτήν αδιαπέρατου εκχειλιστή (n=0.0). Διερευνάται η επίδραση του η στην παροχή Q του εκχειλιστή όπως επίσης και η επίδραση του μήκους του εκχειλιστή L στην παροχή Q. Υπολογίζεται ο συντελεστής παροχής Cd και διερευνάται η επίδραση της διαπερατότητας στις τιμές του Cd.Discharge in rivers and open channels is measured frequently with impermeable broad-crested weirs. In this study permeable weirs considered as more environmentally friendly, are investigated. Two permeable weirs with porosity n=0.42 and n=0.55 are used and their discharge capacity is compared with that of an impermeable weir (n=0.0). The effects of the porosity n and the weir length L on the weir discharge Q are investigated. The discharge coefficient Cd is calculated and the influence of permeability on Cd is investigated

Gravity currents in a vegetated valley of trapezoidal shape

In this study lock-exchange experiments are performed in a tank of rectangular upper cross section and a lower vegetated valley of trapezoidal shape to study the effect of drag resistance, due to vegetation, on gravity currents. Many natural and man-made channels are approximately trapezoidal. For the simulation of the vegetation the bed is covered by flexible grass vegetation (height of vegetation, hv=2.0cm) of different submergence ratio hv/H (hv=height of vegetation, H=water depth). The motion of the gravity current is monitored with a digital video of high definition, the front velocity is measured and the height of the front is captured. Twenty four experiments are performed, twelve inside the trapezoidal section (H/Htr=0.4, 0.6 or 0.8) and twelve over the trapezoidal section (H/Htr=1.2, 1.4 or 1.6). The initial Reynolds number, based on the height of the valley and the reduced gravity, is greater than 10000 for all cases indicating that the gravity currents are turbulent. Results are compared with those of similar experiments without vegetation (Keramaris and Prinos, 2010) and hence the effect of the vegetation drag resistance on the motion of the current is investigated. The main conclusion of this study is that the shape of the tank plays a significant role in the propagation of gravity currents. The presence of trapezoidal increases the velocity of gravity currents in comparison with triangular or orthogonal shape