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61.
Integrated Approaches in Urban Storm Drainage: Where Do We Stand?   总被引:1,自引:0,他引:1  
Integrated approaches to urban stormwater drainage management are being increasingly advocated as necessary for advancing more sustainable and holistic management of urban water environments. In this paper, the status of integrated approaches in the management of urban stormwater discharges to receiving waterways is summarized. The starting point of the paper is with the recent scientific contributions, revealing that integration is being pursued and implemented predominantly at two conceptual levels. These include 1) integrating the technical system with the receiving waterway environment, and 2) considering the interaction and influence of the human system with the technical system through processes such as stakeholder and public participation. Additionally, it is argued that the evolving shift towards the implementation of water-quality-based strategies advances the need for further development and application of integrated models and approaches. The cases of online physically based models for predictive control and integrated source control and public participation are presented as examples of such ongoing developments in pursuit of integrated urban stormwater management.  相似文献   
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63.
The impact of a realistic warming scenario on the metabolic physiology of early cephalopod (squid Loligo vulgaris and cuttlefish Sepia officinalis) life stages was investigated. During exposure to the warming conditions (19 °C for the western coast of Portugal in 2100), the increase in oxygen consumption rates throughout embryogenesis was much steeper in squid (28-fold increase) than in cuttlefish (11-fold increase). The elevated catabolic activity–accelerated oxygen depletion within egg capsules, which exacerbated metabolic suppression toward the end of embryogenesis. Squid late-stage embryos appear to be more impacted by warming via metabolic suppression than cuttlefish embryos. At all temperature scenarios, the transition from encapsulated embryos to planktonic paralarvae implied metabolic increments higher than 100 %. Contrary to the nektobenthic strategy of cuttlefish newborns, the planktonic squid paralarvae rely predominantly on pulsed jet locomotion that dramatically increases their energy requirements. In the future, hatchlings will require more food per unit body size and, thus, feeding intake success will be crucial, especially for squid with high metabolic rates and low levels of metabolic reserves.  相似文献   
64.
Surprisingly little attention is paid to the role of digital technology and related forms of data production, storage, processing, and sharing in humanitarian governance. This paper uses Michael Barnett's ( 2013 ) conceptualisation of humanitarian governance when arguing for a better accounting of technology in literature on humanitarian governance. Specifically, it proposes a two‐fold alertness to governance of (a) the uses of new technology and (b) that which is produced by digital technologies. This elucidates important issues, including that of access to digitalised data collected from humanitarian subjects, with implications for their (in)security. The paper concludes by suggesting that access is no longer ‘only’ about challenges of gaining access to vulnerable populations, but also about challenges of preventing access to vulnerable digital bodies and their use for aggressive purposes. In short, access and protection acquire a new dimension and analyses of humanitarian governance must be more attentive to the role of digital technology.  相似文献   
65.
Residues of halogenated pollutants bioaccumulated in eggs of the south polar skua (Catharacta maccormicki) from the Antarctic were extracted, purified, and fractionated. The target fraction which contained the bulk of the chloropesticides was concentrated and incubated with cell suspensions of the isolated bacterium Sulfurospirillum multivorans (formerly Dehalospirillum multivorans). S. multivorans was previously identified as a good anoxic transformer of several halogenated compounds. The compounds of technical toxaphene 2-endo,3-exo,5-endo,6-exo,8,8,10,10-octachlorobornane (B8-1413, also known as P-26) and 2-endo,3-exo,5-endo,6-exo,8,8,9,10,10-nonachlorobornane (B9-1679, also known as P-50) as well as 1,1-dichloro-2,2-bis(p-chlorophenyl)ethene (p,p′-DDE) and 1-exo,2-exo,4,5,6,7,8,8-octachloro-2,3-exo-epoxy-3a,4,7,7a-tetrahydro-4,7-methanoindene (oxychlordane) were present at a sufficiently high concentration and hence useful for studying the anaerobic transformation by the bacterium. When treated with S. multivorans, B8-1413 and B9-1679 were almost quantitatively transformed within 1 day. For B9-1679, the major metabolite was found to be 2-endo,3-exo,5-endo,6-exo,8,9,10-heptachlorobornane (B7-1001). Compared to the toxaphenes, transformation of oxychlordane and p,p′-DDE was significantly slower. Even after seven days, about 10% of the initial pool was detected in the extracts. 1-chloro-2,2-bis(p-chlorophenyl)ethene (p,p′-DDMU) was identified as a transformation product of p,p′-DDE. The four compounds in this study comprise some of the most persistent chloropesticide residues found in marine birds. In case there is sufficient transformation before they reach the top predators, the bioaccumulative potential can be significantly reduced.  相似文献   
66.
Although counterintuitive at first sight, filial cannibalism is common in the animal kingdom and has been recognized as a mechanism to increase the cannibalizing parent’s lifetime reproductive success. However, previous evidence is often inconclusive and the adaptiveness of filial cannibalism is still not fully understood. We here address the notion that parents do not cannibalize at random but preferably consume offspring with a particular phenotype. To assess if differences in developmental stage and thus reproductive value of eggs trigger such selectivity, we experimentally presented male common gobies (Pomatoschistus microps) with two differently aged egg clutches within mixed broods. We found that males consumed significantly more young than old eggs. This result indicates that parents are not only able to discriminate between eggs based on developmental stage, but might use this to reduce the cost of partial filial cannibalism by selectively removing eggs of lower reproductive value.  相似文献   
67.
Pneumatic waste collection systems are becoming increasingly popular in new urban residential areas, and an attractive alternative to conventional vehicle-operated municipal solid waste (MSW) collection also in ready-built urban areas. How well pneumatic systems perform in ready-built areas is, however, an unexplored topic. In this paper, we analyze how a hypothetical stationary pneumatic waste collection system compares economically to a traditional vehicle-operated door-to-door collection system in an existing, densely populated urban area. Both pneumatic and door-to-door collection systems face disadvantages in such areas. While buildings and fixed city infrastructure increase the installation costs of a pneumatic system in existing residential areas, the limited space for waste transportation vehicles and containers cause problems for vehicle-operated waste collection systems. The method used for analyzing the cost effects of the compared waste collection systems in our case study takes into account also monetized environmental effects of both waste collection systems. As a result, we find that the door-to-door collection system is economically almost six times more superior. The dominant cost factor in the analysis is the large investment cost of the pneumatic system. The economic value of land is an important variable, as it is able to reverse the results, if the value of land saved with a pneumatic system is sufficiently high.  相似文献   
68.
Environmental-stress-mediated geographic variation in reproductive parameters has been little studied in natural vertebrate populations outside the context of climatic variation. Based on life-history theory, an increase in the degree of environmental stress experienced by a population should lead to (1) a shift in reproductive allocation from fecundity to offspring quality, (2) stronger trade-offs between reproductive parameters, and (3) changes in the relationship between female phenotype and maternal investment. To test these predictions, we investigated geographic variation in maternal investment of moor frogs (Rana arvalis) in relation to breeding site acidity (pH 4-8). We found that mean egg size increased and clutch size and total reproductive output (TRO) decreased with increasing acidity among 19 Swedish moor frog populations. Tests for variation and co-variation in maternal investment and female size and age in 233 females from a subset of four acid origin (AO) and four neutral origin (NO) populations revealed that clutch size and TRO increased with female size in both acid and neutral environments. However, in AO populations, egg size also increased with female size, and clutch size and TRO with female age, whereas in NO populations, egg size increased with female age. The strength of the egg-size-clutch-size tradeoff tended to be stronger in AO than in NO females as expected if the former experience stronger environmental constraints. All in all, these results suggest that environmental acidification selects for investment in larger eggs at a cost to fecundity, imposes negative effects on reproductive output, and alters the relationship between female phenotype and maternal investment.  相似文献   
69.
In chemotherapy, various anti-cancer drugs with different mechanisms of action are used and may represent different risk of undesirable delayed side effects in treated patients as well as in occupationally exposed populations. The aim of the present study was to evaluate genotoxic potential of four widely used anti-cancer drugs with different mechanisms of action: 5-fluorouracil (5-FU), cisplatin (CDDP) and etoposide (ET) that cause cell death by targeting DNA function and imatinib mesylate (IM) that inhibits targeted protein kinases in cancer cells in an experimental model with human hepatoma HepG2 cells. After 24 h of exposure all four anti-cancer drugs at non-cytotoxic concentrations induced significant increase in formation of DNA double strand breaks (DSBs), with IM being the least effective. The analysis of the changes in the expression of genes involved in the response to DNA damage (CDKN1A, GADD45A, MDM2), apoptosis (BAX, BCL2) and oncogenesis (MYC, JUN) showed that 5-FU, CDDP and ET upregulated the genes involved in DNA damage response, while the anti-apoptotic gene BCL2 and oncogene MYC were downregulated. On the contrary, IM did not change the mRNA level of the studied genes, showing different mechanism of action that probably does not involve direct interaction with DNA processing. Genotoxic effects of the tested anti-cancer drugs were observed at their therapeutic concentrations that may consequently lead to increased risk for development of delayed adverse effects in patients. In addition, considering the genotoxic mechanism of action of 5-FU, CDDP and ET an increased risk can also not be excluded in occupationally exposed populations. The results also indicate that exposure to 5-FU, CDDP and ET represent a higher risk for delayed effects such as cancer, reproductive effects and heritable disease than exposure to IM.  相似文献   
70.
In 2006, a controlled infection study was performed in the ‘Kranzberger Forst’ to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2× ozone) and three control trees (ambient = 1× ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection.  相似文献   
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