scholarly journals Surface stormwater runoff in the formation of contemporary urban surface deposited sediments

2019 ◽  
Vol 98 ◽  
pp. 07028
Author(s):  
Andrian Seleznev ◽  
Ilia Yarmoshenko ◽  
Georgy Malinovsky ◽  
Daria Kiseleva ◽  
Ekaterina Ilgasheva ◽  
...  

Surface runoff represents one of the major mechanism connecting sources, transport, deposition and storage of the particle matter in urban sediment cascade. The urban surface deposited sediment represents a medium for the transport and nonpoint source of pollution in cities. The study is aimed to characterize the role of surface stormwater runoff in accumulation of the contemporary surface deposited sediments in the urban environment taking to account the seasonal factor. The study was conducted on the example of residential area of Ekaterinburg, Russia. The role of the surface stormwater runoff in the formation of the urban surface deposited sediments was discussed. The snow and dirt mixture accumulates surface runoff and pollutants in it during the winter season in an urban area. A large supply of water accumulated in the snow cover during the cold period contributes to the formation of large volumes of snow-mud mixture during spring. The active snowmelt in the spring leads to the formation of snow-dirt sludge and transfer of the sedimentary material.

2021 ◽  
Vol 943 (1) ◽  
pp. 012001
Author(s):  
G. Cruz ◽  
M. Lingad

Abstract In recent years, stormwater control measures (SCMs) such as permeable concrete pavement have been experimentally investigated and used to manage hydrologic and water quality impacts of stormwater runoff. Research revealed the potential of permeable pavement in reducing and delaying peak flow rate, reducing runoff volume, and capturing heavy metals and other particulate-bound pollutants from stormwater runoff. However, few studies have evaluated the effects of permeable pavement on nutrients in stormwater runoff. This research aims to produce permeable reactive concrete (PRC) from waste fly ash, waste gypsum board and waste coco peat and to investigate its effectiveness in removing nutrient contamination present in stormwater or urban surface runoff. The raw materials underwent through granulation process to produce granulated filtering media (GFM). Cylindrical samples of PRC were then made and subjected to various physical and water quality tests. The use of GFM as partial coarse aggregates of PRC for urban surface runoff management and nutrient contamination removal has been tested and evaluated. After performing all the tests, the researchers concluded that GFM as partial coarse aggregates of PRC is effective due to the significant increase in infiltration rate of the entire sample compared to the traditional permeable concrete that has an average infiltration rate of 2-6 mm/s. The results in the water quality test revealed that PRC with GFM as partial coarse aggregates lessen the nitrate, phosphate, and ammonia that are present on urban surface runoff.


Author(s):  
Lidiya Derbenyova

The article explores the role of antropoetonyms in the reader’s “horizon of expectation” formation. As a kind of “text in the text”, antropoetonyms are concentrating a large amount of information on a minor part of the text, reflecting the main theme of the work. As a “text” this class of poetonyms performs a number of functions: transmission and storage of information, generation of new meanings, the function of “cultural memory”, which explains the readers’ “horizon of expectations”. In analyzing the context of the literary work we should consider the function of antropoetonyms in vertical context (the link between artistic and other texts, and the groundwork system of culture), as well as in the context of the horizontal one (times’ connection realized in the communication chain from the word to the text; the author’s intention). In this aspect, the role of antropoetonyms in the structure of the literary text is extremely significant because antropoetonyms convey an associative nature, generating a complex mechanism of allusions. It’s an open fact that they always transmit information about the preceding text and suggest a double decoding. On the one hand, the recipient decodes this information, on the other – accepts this as a sort of hidden, “secret” sense.


2021 ◽  
Author(s):  
Fabrice Cognasse ◽  
Kathryn Hally ◽  
Sebastien Fauteux-Daniel ◽  
Marie-Ange Eyraud ◽  
Charles-Antoine Arthaud ◽  
...  

AbstractAside from their canonical role in hemostasis, it is increasingly recognized that platelets have inflammatory functions and can regulate both adaptive and innate immune responses. The main topic this review aims to cover is the proinflammatory effects and side effects of platelet transfusion. Platelets prepared for transfusion are subject to stress injury upon collection, preparation, and storage. With these types of stress, they undergo morphologic, metabolic, and functional modulations which are likely to induce platelet activation and the release of biological response modifiers (BRMs). As a consequence, platelet concentrates (PCs) accumulate BRMs during processing and storage, and these BRMs are ultimately transfused alongside platelets. It has been shown that BRMs present in PCs can induce immune responses and posttransfusion reactions in the transfusion recipient. Several recent reports within the transfusion literature have investigated the concept of platelets as immune cells. Nevertheless, current and future investigations will face the challenge of encompassing the immunological role of platelets in the scope of transfusion.


2016 ◽  
Vol 73 (12) ◽  
pp. 2921-2928 ◽  
Author(s):  
Marla C. Maniquiz-Redillas ◽  
Lee-Hyung Kim

Abstract In this research, an infiltration trench equipped with an extensive pretreatment and filter bed consisting of woodchip, sand and gravel was utilized as a low impact development technique to manage stormwater runoff from a highly impervious road with particular emphasis on heavy metal removal. Findings revealed that the major factors influencing the removal of heavy metals were the concentration of the particulate matters and heavy metals in runoff, runoff volume and flow rates. The reduction of heavy metals was enhanced by sedimentation of particulates through pretreatment. Fine particles (<2 mm) had the most significant amount of heavy metals, thus, enhanced adsorption and filtration using various filter media were important design considerations. Sediment was most highly attached on the surface area of woodchip than to other filter media like sand, gravel and geotextile. It is suggested that maintenance must be performed after the end of the winter season wherein high sediment rate was observed to maintain the efficiency of the treatment system.


2021 ◽  
Vol 26 (3) ◽  
pp. 2626-2630
Author(s):  
EVELINA MILCHEVA MARINOVA ◽  
◽  
DIMITAR STOIMENOV DABOV ◽  
YANI TODOROV ZDRAVKOV ◽  
EMILIA KRASIMIROVA NASEVA ◽  
...  

Objective: The purpose of our research is to emphasize the role of underestimated predisposing conditions for microbial keratitis in contact lens users, to draw attention to the complications of wearing contact lenses without ophthalmic examination, and to offer a short questionnaire for fast and easy estimation of the risk factors for bacterial keratitis. Methods: A series of 23 cases of healthy young individuals, treated for bacterial keratitis, provoked а research on the predisposing factors for its development. Results: 55% of the patients had started to wear contact lenses without specific examination. 75% had made mistakes in the hygiene and storage of the lenses. We identified risk factors for development of bacterial keratitis in all cases. Conclusions: A thorough anamnesis and ophthalmic examination are crucial in decision making about contact lens wearing because they could reveal some of the predisposing conditions for the occurrence of ocular complications. The usage of contact lenses without a prescription poses health risks and could have a negative impact on the social and healthcare system.


1997 ◽  
Vol 60 (9) ◽  
pp. 1029-1033 ◽  
Author(s):  
NORMA S. LÁZARO ◽  
ANITA TIBANA ◽  
ERNESTO HOFER

Tonsils and inguinal, mesenteric, and prescapular lymph node samples collected from 115 swine carcasses from two abattoirs and a family-run operation in the State of Rio de Janeiro, Brazil, were cultured for the presence of Salmonella species. Salmonella spp. were detected in 40 (34.8%) of the swine samples with the following distribution; tonsils (31/40, 77.5%), mesenteric lymph nodes (16/40, 40.0%), inguinal lymph nodes, (9/40, 22.5%), and prescapular lymph nodes (7/40, 17.5%), Scalding tank water and environmental swabs collected from the abattoirs were also analyzed. Salmonella spp. were recovered from 13 of 51 (22.5%) of the environmental samples from one of the two abattoirs, none from those from the other abattoir. Salmonella spp. were recovered from the evisceration tables (5/11, 45.5%), the killing room (3/10, 30.0%), the holding pen (2/10, 20.0%), the butchering saw (2/10, 20.0%), and the scalding tank (1/10, 10.0%). The most frequently detected serovar was Salmonella Muenster. The results show the necessity of adopting more effective hygienic measures in the abattoirs as well as in the areas where swine are raised in order to reduce the role of abattoirs and storage facilities in the spread of Salmonella contamination.


1998 ◽  
Vol 78 (1) ◽  
pp. 53-97 ◽  
Author(s):  
FRANK M. FARACI ◽  
DONALD D. HEISTAD

Faraci, Frank M., and Donald D. Heistad. Regulation of the Cerebral Circulation: Role of Endothelium and Potassium Channels. Physiol. Rev. 78: 53–97, 1998. — Several new concepts have emerged in relation to mechanisms that contribute to regulation of the cerebral circulation. This review focuses on some physiological mechanisms of cerebral vasodilatation and alteration of these mechanisms by disease states. One mechanism involves release of vasoactive factors by the endothelium that affect underlying vascular muscle. These factors include endothelium-derived relaxing factor (nitric oxide), prostacyclin, and endothelium-derived hyperpolarizing factor(s). The normal vasodilator influence of endothelium is impaired by some disease states. Under pathophysiological conditions, endothelium may produce potent contracting factors such as endothelin. Another major mechanism of regulation of cerebral vascular tone relates to potassium channels. Activation of potassium channels appears to mediate relaxation of cerebral vessels to diverse stimuli including receptor-mediated agonists, intracellular second messengers, and hypoxia. Endothelial- and potassium channel-based mechanisms are related because several endothelium-derived factors produce relaxation by activation of potassium channels. The influence of potassium channels may be altered by disease states including chronic hypertension, subarachnoid hemorrhage, and diabetes.


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