Urban Heat Islands Strategy Plan Vienna – Implementing Urban Green Infrastructure to Reduce Negative Effects of Urban Heat Islands

Urban heat islands (UHI) have been known since the 19th century (Howard, 1820) and describe the difference in temperature between cities and their rural surroundings. This difference can be up to 12°C (Eliasson, 2000, 31); the phenomenon is caused by the transformation of natural surfaces through e.g. soil sealing, construction of infrastructure and buildings. However, differences in temperature not only occur between cities and their adjacent areas, but also within different parts of cities depending on the provision of green and blue infrastructure as well as on their share of sealed surfaces. The situation is further aggravated by a changing climate. Numerous studies state that the number of heat days (maximum temperature of at least 30°C) as well as the number and duration of heat waves will increase worldwide – especially in cities due to their sealed surfaces, building density and lack of green space (Formayer et al., 2008; Bowler et al., 2010). This problem will become even more crucial in the future: in 2005 approx. half of the world population lived in urban regions and this number is predicted to rise by up to nearly two thirds by 2050 (Schlünzen, 2012). Consequences of those growing cities and expanding urban areas are further densification of settlement areas and loss of open and green space; this strengthens the urban heat islands effect even more. Urban heat islands can have negative effects on human health and wellbeing with sensitive groups such as the elderly being especially affected (Allex et al., 2013). To counteract UHI and their negative effects, the “Urban Heat Islands Strategy Plan Vienna” has been elaborated as part of a Central Europe project (www.http://eu-uhi.eu/, 2011-2014). The aim was the development of a strategy for the City of Vienna to implement open space planning as well as urban ecology measures to reduce the negative aspects of UHI. Within the project, a guideline has been elaborated by the project team and members of the Environmental Protection Department Vienna (MA 22) to support planners, architects as well as members of the Vienna City Administration, to show possibilities of technical and strategic measures against UHI as well as their potential to reduce urban heat, and to point out planning tools and planning levels. The guideline is available online (https://www.wien.gv.at/umweltschutz/raum/uhi-strategieplan.html, in German)

Urban green infrastructure planning as a contribution to the smart ‘green’ city

The urban green infrastructure is getting due to the strong growth of the City of Vienna under increasing pressure. A foresighted planning of green and open spaces is necessary to obtain the different "Ecosytem Services" - provision-related services, regulatory services, cultural services and support services (MEA 2005). Additionally an increase in the number of hot days and thus an increase of the heat load in the city is predicted for Vienna (ZAMG 2012). Again, making a foresighted planning of green and open spaces is a significant contribution to meet these climatic challenges (Kuffner A. 2012, Hagen et al. 2010). Based on the concept of "green infrastructure" (Pauleit et al. 2011) and the ecosystem services of these, it is shown which contribution - in particular to reduce the heating of the city - they can make to the Smart City concept

Characterization of human and rodent native and recombinant adenosine A2B receptors by radioligand binding studies

Adenosine A2B receptors of native human and rodent cell lines were investigated using [3H]PSB-298 [(8-{4-[2-(2-hydroxyethylamino)-2-oxoethoxy]phenyl}-1-propylxanthine] in radioligand binding studies. [3H]PSB-298 showed saturable and reversible binding. It exhibited a KD value of 60 ± 1 nM and limited capacity (Bmax = 3.511 fmol per milligram protein) at recombinant human adenosine A2B receptors expressed in human embryonic kidney cells (HEK-293). The addition of sodium chloride (100 mM) led to a threefold increase in the number of binding sites recognized by the radioligand. The curve of the agonist 5′-N-ethylcarboxamidoadenosine (NECA) was shifted to the right in the presence of NaCl, while the curve of the antagonist PSB-298 was shifted to the left, indicating that PSB-298 may be an inverse agonist at A2B receptors. Adenosine A2B receptors were shown to be the major adenosine A2 receptor subtype on the mouse neuroblastoma x rat glioma hybrid cell line NG108-15 cells. Binding studies at rat INS-1 cells (insulin secreting cell line) demonstrated that [3H]PSB-298 is a selective radioligand for adenosine A2B binding sites in this cell line

A modifier screen in the eye reveals control genes for Krüppel activity in the Drosophila embryo

Irregular facets (If) is a dominant mutation of Drosophila that results in small eyes with fused ommatidia. Previous results showed that the gene Krüppel (Kr), which is best known for its early segmentation function, is expressed ectopically in If mutant eye discs. However, it was not known whether ectopic Kr activity is either the cause or the result of the If mutation. Here, we show that If is a gain-of-function allele of Kr. We then used the If mutation in a genetic screen to identify dominant enhancers and suppressors of Kr activity on the third chromosome. Of 30 identified Kr-interacting loci, two were cloned, and we examined whether they also represent components of a natural Kr-dependent developmental pathway of the embryo. We show that the two genes, eyelid (eld) and extramacrochaetae (emc), which encode a Bright family-type DNA binding protein and a helix-loop-helix factor, respectively, are necessary to achieve the singling-out of a unique Kr-expressing cell during the development of the Malpighian tubules, the excretory organs of the fly. The results indicate that the Kr gain-of-function mutation If provides a tool to identify genes that are active during eye development and that a number of them function also in the control of Kr-dependent developmental processes

Monoglyceride Lipase Deficiency in Mice Impairs Lipolysis and Attenuates Diet-induced Insulin Resistance*

Monoglyceride lipase (MGL) influences energy metabolism by at least two mechanisms. First, it hydrolyzes monoacylglycerols (MG) into fatty acids and glycerol. These products can be used for energy production or synthetic reactions. Second, MGL degrades 2-arachidonoyl glycerol (2-AG), the most abundant endogenous ligand of cannabinoid receptors (CBR). Activation of CBR affects energy homeostasis by central orexigenic stimuli, by promoting lipid storage, and by reducing energy expenditure. To characterize the metabolic role of MGL in vivo, we generated an MGL-deficient mouse model (MGL-ko). These mice exhibit a reduction in MG hydrolase activity and a concomitant increase in MG levels in adipose tissue, brain, and liver. In adipose tissue, the lack of MGL activity is partially compensated by hormone-sensitive lipase. Nonetheless, fasted MGL-ko mice exhibit reduced plasma glycerol and triacylglycerol, as well as liver triacylglycerol levels indicative for impaired lipolysis. Despite a strong elevation of 2-AG levels, MGL-ko mice exhibit normal food intake, fat mass, and energy expenditure. Yet mice lacking MGL show a pharmacological tolerance to the CBR agonist CP 55,940 suggesting that the elevated 2-AG levels are functionally antagonized by desensitization of CBR. Interestingly, however, MGL-ko mice receiving a high fat diet exhibit significantly improved glucose tolerance and insulin sensitivity in comparison with wild-type controls despite equal weight gain. In conclusion, our observations implicate that MGL deficiency impairs lipolysis and attenuates diet-induced insulin resistance. Defective degradation of 2-AG does not provoke cannabinoid-like effects on feeding behavior, lipid storage, and energy expenditure, which may be explained by desensitization of CBR