REVIEW | doi:10.20944/preprints202010.0295.v2
Subject: Arts & Humanities, Architecture And Design Keywords: stormwater drainage; urban flood; urban drainage management; food disaster management
Online: 15 October 2020 (12:05:44 CEST)
Stormwater drainage and urban flooding are the popular issues in policy agendas and academia. Although the research on these title increases steadily an integrated review on stormwater drainage and urban flood with a focus on pluvial flooding has yet to be produced. This paper presents a critical review on stormwater drainage and urban flood based on 78 selected journal papers published over the period of 1990 to 2018. The review focus on pluvial flooding to relate urban stormwater drainage management and urban flood disaster management and to show the links between the two. The methods taken to manage urban stormwater drainage and urban flooding as well as the complexity of achieving a comprehensive urban flood disaster management are evaluated and discussed. To better understand the concepts behind urban flood and improve the urban flood risk management strategies, recommendation of future research directions are also provided.
ARTICLE | doi:10.20944/preprints201902.0024.v1
Subject: Engineering, Civil Engineering Keywords: infiltration based BMP’s; flood; infiltration; clogging; soil permeability; underdrain; soil saturation rate; drainage basin; urban drainage
Online: 3 February 2019 (03:05:39 CET)
Infiltration based stormwater best management practices bring considerable economic, social and ecological benefits. Controlling stormwater quantity and quality are primarily important to prevent urban flooding and minimizing loads of pollutants to the receiving waters. However, there have been growing concerns about how the traditional design approach contributes to the failure of infiltration based BMP’s that have caused flooding, ponding, prolonged movement of surface water, and frequent clogging, etc. Many of these problems were due to the fact that the current design approaches of stormwater BMP’s only focus on surface hydrology and give little or no attention to the underline subsoil permeability rate and other constraints during the design and sizing process. As a result, we are exhibiting many newly constructed infiltration based BMP’s are failing to function well. This paper presents and demonstrates a new paradigm shift in designing infiltration-based stormwater BMP’s by combining subsurface hydrology and undelaying native soil constraints to establish acceptable criteria for sizing infiltration based BMPs.
ARTICLE | doi:10.20944/preprints202001.0250.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: fen; paludiculture; rewetting; drainage; matter fluxes; interdisciplinary
Online: 29 February 2020 (10:44:42 CET)
Of all terrestrial ecosystems, peatlands store carbon most effectively in long-term scales of millennia. However, many peatlands have been drained for peat extraction or agricultural use. This converts peatlands from sinks to sources of carbon, causing approx. 5% of the anthropogenic greenhouse effect and additional negative effects on other ecosystem services. Rewetting peatlands can mitigate climate change and may be combined with management in the form of paludiculture. Rewetted peatlands, however, do not equal their pristine ancestors and their ecological functioning is not understood. This holds especially for groundwater-fed fens. Their functioning results from manifold interactions and can only be understood following an integrative approach of many relevant fields of science, which we merge in the interdisciplinary project WETSCAPES. Here, we address interactions among water transport and chemistry, primary production, peat formation, matter transformation and transport, microbial community and greenhouse gas exchange using state of the art methods. We record data on six study sites spreading across three common fen types (Alder forest, percolation fen, and coastal fen) each in drained and rewetted state. First results showed that indicators reflecting more long-term effects like vegetation and soil chemistry showed a stronger differentiation between drained and rewetted state than variables with more immediate reaction to environmental change, like greenhouse gas (GHG) emissions. Variations in microbial community composition explained differences in soil chemical data as well as vegetation composition and GHG exchange. We show the importance of developing an integrative understanding of managed fen peatlands and their ecosystem functioning.
ARTICLE | doi:10.20944/preprints202208.0540.v1
Subject: Earth Sciences, Atmospheric Science Keywords: urban waterlogging risk; extreme rain; drainage capacity; Shanghai
Online: 31 August 2022 (08:55:36 CEST)
Waterlogging induced by rain in urban areas has a potential risk impact on property and safety. This paper focuses on the impact of rain on waterlogging and evaluates the waterlogging risk in the central city of Shanghai. A simplified waterlogging depth model is developed in different areas with different drainage capacity and rainfall in consumption of simplifying the effect of complex terrain characteristics and hydrological situation. Based on urban waterlogging depth and its classification collection, a Rain-induced Urban Waterlogging Risk Model(RUWRM) is further established to evaluate waterlogging risk in the central city. The results show that waterlogging depth is closely linked with rainfall and drainage, with a linear relationship between them. More rainfall leads to higher waterlogging risk, especially in the central city with imperfect drainage facilities. Rain-induced urban waterlogging risk model can rapidly gives the waterlogging rank caused by rainfall with a clear classification collection. The results of waterlogging risk prediction indicate that it is confident to get the urban waterlogging risk rank well and truly in advance with more accurate rainfall prediction. This general study is a contribution that allows the public, policy makers and relevant departments of urban operation to assess the appropriate management to reduce traffic intensity and personal safety or strategy to lead to less waterlogging risk.
CASE REPORT | doi:10.20944/preprints201806.0117.v1
Subject: Earth Sciences, Environmental Sciences Keywords: sulfur; reclamation; acid mine drainage; salinity; soil contamination
Online: 7 June 2018 (11:21:57 CEST)
Sulfur contamination of topsoil, spatial distribution of contamination and surface water chemistry were investigated on an area of over 200 ha of a new forest ecosystem. Common birch and Scots pine growth reaction, vitality and nutrients supply, as well as wood small-reed (Calamagrostis epigejos (L.) Roth) chemical composition were assayed. The chemistry dynamics of soil leaching and the sulfur load leached from the sulfur contaminated soil-substrates were analyzed. The remediation effect of the birch and pine litter was assayed in an experiment under controlled conditions. It was found that reclamation was effective in a majority of the post-mining site, however hot-spots with sulfur contamination reaching even 45,000 mg kg-1, pH <2.0, and EC 6,500 µS cm-1 were reported. Surface waters typically displayed elevated concentrations of sulfate ions (average 935.13 mg L-1), calcium ions (up to 434 mg L-1) and high EC (average 1.795 µS cm-1), which was connected both with sulfur contamination and sludge lime used in neutralization. Wood small-reed was found to be species adapting well to the conditions of elevated soil salinity and sulfur concentration. We noted that an addition of organic matter had a significant impact on the chemistry of soil solutions but did not indicate in short term experiment a remediation effect by increased sulfur leaching.
ARTICLE | doi:10.20944/preprints201802.0033.v1
Subject: Physical Sciences, Fluids & Plasmas Keywords: Tank drainage; Power law MHD fluid; Analytical solution
Online: 5 February 2018 (11:41:11 CET)
This paper investigates the tank drainage problem of an isothermal, unsteady, incompressible electrically conducting Power law fluid. Analytic solution have been obtained from governing continuity and momentum equations subject to appropriate boundary conditions by using Perturbation method. The Power law fluid model solution without MHD is retrieved from this proposed model on substitution . Declaration on behalf of velocity profile, volume flux, average velocity, connection of time with respect to length of the tank and requirement of time for whole drainage of fluid are acquired. Special effects of numerous emerging parameter’s on velocity profile vz and depth of the fluid in the tank are graphically presented. Keywords: Tank drainage, Power law MHD fluid, Analytical solution.
ARTICLE | doi:10.20944/preprints202010.0194.v1
Subject: Engineering, Automotive Engineering Keywords: urban drainage; SWMM5.1; land use; hydraulic performance; Shire Endaslasse
Online: 9 October 2020 (10:26:40 CEST)
The stormwater drainage problem is one of the major challenges facing in Shire Endaslasse town, Ethiopia. In a town, Street flooding and overtopping drainage system problems are occurring during the rainy season. This causes ponding which poses difficulties in ease of transportation and it hinders the day-to-day activity of the people. So, the study focuses on the performance of the stormwater drainage system in Shire Endaslasse town using Arc GIS and SWMM5.1. For this study, the primary data were collected by field surveys and interviews with the council body. Simulation results for storm events show that in some of the drainage systems in different regions of Shire Endaslasse town have flooded. During the field observation, the drainage structures are filled with solid wastes, inadequate inlet and outlet structures and some of the top element of the manhole have been broken this may cause a problem of aesthetic and healthy at large it may increase flood risk. The flooding risk in the drainage systems is very high due to the drainage system is undersized to cope with the current rainfall rates, but also is very limited to face the upcoming predicted rainfall.
ARTICLE | doi:10.20944/preprints202007.0236.v1
Subject: Chemistry, Other Keywords: trace metals; mine drainage remediation; zinc; red media; biochar
Online: 11 July 2020 (09:36:40 CEST)
The river Teign in Devon has come under scrutiny for failing to meet Environmental Quality Standards for ecotoxic metals due to past mining operations. A disused mine known as Bridford Barytes mine, has been found to contribute a significant source of Zn, Cd and Pb to the river. Recently, studies have been focused on the remediation of such mine sites using low-cost treatment methods to help reduce metal loads to the river downstream. Red mud is a waste product from the aluminium industry, the utilization of this resource has proven an attractive low-cost treatment method for adsorbing toxic metals. Adsorption kinetics and capacity experiments reveal metal removal efficiencies of up to 70% within the first 2 hours when red mud is applied in pelletized form. Biochar is another effective adsorbent with the potential to remove >90% Zn using agricultural feedstock. Compliance of the Teign has been investigated by analysing dissolved metal concentrations and bioavailable fractions of Zn to assess if levels are of environmental concern. By applying a Real-World Application Model, this study reveals that compressed pellets and agricultural biochar offer an effective, low-cost option to reducing metal concentrations and thus improving the quality of the river Teign.
ARTICLE | doi:10.20944/preprints201807.0168.v2
Subject: Engineering, Civil Engineering Keywords: urban floods, stormwater pipe network, drainage density, flood risk
Online: 18 July 2018 (09:27:47 CEST)
In mega cities such as Seoul in South Korea, it is very important to protect the city from the flooding even for the short time of period due to the enormous amount of economic damage. In impervious area of the city, stormwater pipe network is commonly applied to discharge rainfall to the outside of catchment. Therefore, the stormwater pipe network in urban catchment should be carefully designed to discharge the runoff quickly and efficiently. In this study, different types of structures in stormwater pipe network were evaluated using the relationship between the peaks rainfall and runoff in urban catchments in South Korea. More than 400 historical rainfall events were applied in five urban catchments to estimate peak runoff from different type of network structures. Linear regression analysis was implemented to estimate peak runoffs. The coefficient of determination of the regressions were higher than 0.9 which means the regression model represent very well the relationship between the two peaks. However, the variation of the prediction becomes large as the peak rainfall increases and the variation become even larger when the network structure is branched. Therefore, it depends on the structure of stormwater pipe network. When the water paths in the pipe network is unique (branched network), the increased amount of rainfall is congested around the rainwater inlets and the uncertainty of peak runoff prediction is increased. If there are many possible water paths depending on the amount of discharge (looped network), the increased rainfall is discharged more quickly through the many water paths. This can be a way to represent the reliability of the stormwater pipe network. The structures of stormwater pipe network is evaluated using drainage density which is the length of pipes over the unit catchment area and 95% confidence interval. As a result, the 95% confidence interval is increased as the drainage density is increased because the accuracy of peak runoff prediction is decreased. As mentioned earlier, because the looped networks have many alternative water flowing paths, elimination time of rainfall from the catchments become short, the 95% confidence interval become narrow, and the reliability of peak runoff prediction become high. Therefore, it is beneficial to install looped stormwater pipe network within the affordable budget. It is important factor to determine the amount of complexity in stormwater pipe network to decrease the risk of urban flooding.
ARTICLE | doi:10.20944/preprints202201.0059.v1
Subject: Earth Sciences, Geochemistry & Petrology Keywords: microporous carbonates; multimodal porosity; primary drainage; capillary invasion; mixed wettability
Online: 6 January 2022 (10:03:11 CET)
Improved oil recovery from tight carbonate formations may provide the world with a major source of lower-rate power over several decades. Here we provide an overview of the Arab D formation in the largest oil field on earth, the Ghawar. We investigate the occurrence of microporosity of different origins and sizes using scanning electron microscopy (SEM) and pore casting techniques. Then, we present a robust calculation of the probability of invasion and oil saturation distribution in the nested micropores using mercury injection capillary pressure data available in the literature. We show that large portions of the micropores in Arab D formation would have been bypassed during primary drainage unless the invading crude oil ganglia were sufficiently long. Considering the asphaltenic nature of oil in the Ghawar, we expect the invaded portions of the pores to turn mixed-wet, thus becoming inaccessible to waterflooding until further measures are taken to modify the system’s chemistry.
ARTICLE | doi:10.20944/preprints201906.0263.v1
Subject: Engineering, Other Keywords: acid mine drainage; contaminated areas; environmental; heavy metals; public health
Online: 26 June 2019 (07:41:12 CEST)
The mining industry is known for the intense environmental impacts it triggers, especially when it is developed in an open environment. Pit lakes are formed in depleted deposits and may be promising opportunities for use by society as well as troubling environmental liabilities. While these artificial basins are increasing numerically in many parts of the world, they are still little known researchers in the Environmental Sciences, which makes their environmental management challenging. The main objective of this study was to evaluate the environmental quality of sediments from three deactivated open-pit gold mines, located in the Mara Rosa, Brazil, through chemical, ecotoxicological and genotoxicology analyses. For this purpose, we collected samples in the dry season boom, and subsequently, we analysed metals. In sequence, acute ecotoxicological and a genotoxicology test (comet assay) were developed with Danio rerio fishes, in concentrations of 3.12%; 6.25%; 12.5%; 25%; 50% and 100%, in addition to the control group. The results indicated that the three lakes are environmentally compromised, especially Lago Azul, whose waters and sediments are undergoing an intense process of geological conditioning. Our results did not verify the ecotoxicity of the sediments of any of the lakes, only behavioural alterations in the test organisms exposed to the concentrations of 25%, 50% and 100% of the samples obtained in the Lago Azul. About the sediments, DNA damage at Danio rerio was detected in the three investigated environments, although fishes kept in the water sampled at Lago Azul presented the most extension of DNA damages.
ARTICLE | doi:10.20944/preprints201703.0146.v1
Subject: Earth Sciences, Environmental Sciences Keywords: acid mine drainage; bioremediation technology; sulfate reducing bacteria; coal mining
Online: 17 March 2017 (22:27:05 CET)
Sulfate, the main dissolved contaminant in acid mine drainage (AMD), is ubiquitous in watersheds affected by coal and metal mining operations worldwide. Engineered passive bioremediation systems (PBS) are low-cost technologies that remediate sulfate contamination by promoting (1) precipitation of sulfate-bearing compounds, such as schwertmannite and gypsum; and (2) microbially-mediated sulfate reduction (BSR) to sulfide with subsequent precipitation of sulfide minerals. In this study, chemical and sulfur isotopic data are used to infer multiple pathways for sulfate sequestration in the Tab-Simco PBS. By simultaneously monitoring sulfate concentrations and δ34SSO4 values at four sampling points across the PBS, we (1) identified that the organic layer within the bioreactor was the primary site of BSR processes contributing to sulfate sequestration; (2) observed seasonal variations of BSR processes; (3) estimated that initially the BSR processes contributed up to 30% to sulfate sequestration in the Tab-Simco bioreactor; and (4) determined that BSR contribution to sulfate sequestration continuously declined over the PBS operational lifetime. Together, our results highlight the utility of combining geochemical and microbial fingerprinting techniques to decipher complementary processes involved in sulfur cycling in a PBS as well as the value of adding the sulfur isotope approach as an essential tool to help understand, predict, prevent and mitigate sulfate contamination in AMD-impacted systems.
ARTICLE | doi:10.20944/preprints201801.0158.v1
Subject: Engineering, Other Keywords: Sponge city; Active, Beautiful, Clean water design; sustainable drainage systems; water-sensitive urban drainage systems; low impact developments; best management practices; literature mining; literature review
Online: 17 January 2018 (12:34:38 CET)
As the increase threat of flood risk and environmental safety due to the urbanization, Sponge city research has been attracting extensive attention both in practical and theoretical research field. To date, there are only scattered studies about Sponge city. Moreover, vary names of Sponge city prevalent in different countries, which leads to disconnection of literature in the same field of Sponge city. In this paper, a thorough systematic literature mining of Sponge city is presented. A literature analysis system is created, which includes literature export from Web of Sciences and systematic analysis via NoteExpress and CiteSpace. Some literature statistical results are derived. Challenges and opportunities for future research are anticipated. Our goals are to promote this promising thought, summarize past research, and identify issues for future research to create impacts on the practice of Sponge city.
ARTICLE | doi:10.20944/preprints201804.0055.v1
Subject: Engineering, Civil Engineering Keywords: IDF curves; urban drainage; regional climate model; bias correction; climate changes
Online: 4 April 2018 (08:26:21 CEST)
Drainage systems are usually dimensioned for design storms based on intensity-duration-frequency (IDF) curves of extreme precipitation. For each location, different IDF curves are established based on local hydrological conditions. Recent research shows that these curves also vary with time, and should be updated with recent data. The purpose of this study is to evaluate IDF curves obtained from precipitation simulations from the Eta RCM, comparing them with IDF curves obtained from data of a rainfall station. Climate models can be a useful tool for assessing the impacts of climate changes on drainage systems, referring precipitation forecasts. In this study, the Eta RCM was forced by two global climate models: HadGEM2-ES and MIROC5. The bias of the precipitation data, generated by RCM models, was corrected using a Gamma distribution. The Juqueriquerê River Basin, in the cities of Caraguatatuba and São Sebastião, São Paulo State, Brazil, was chosen as a case study. The results show a good correlation between the IDF curves of simulated and observed rainfall for the control period (1960-2005), indicating the strong possibility of using the Eta RCM precipitation forecasts for 2007 - 2099 to establish future IDFs thereby, taking into account climate changes in urban drainage design.
ARTICLE | doi:10.20944/preprints202212.0538.v1
Subject: Engineering, Energy & Fuel Technology Keywords: horizontal gas well; liquid-carrying model; tubing depth; gas drainage; fluid energy
Online: 28 December 2022 (10:01:08 CET)
As the structure of horizontal gas wells is more complicated than that of vertical wells, the form of the liquid-carrying in different sections does not well agree. This makes it problematic to apply the widely used liquid-carrying theory of vertical gas wells in horizontal gas wells. Since the theory focused on the critical gas flow rate, it cannot quantify how much liquid it can remove. Simultaneously, it ignores the fact that the liquid-carrying ability of gas flow is limited and the producing liquid has a certain amount of flowing energy. In this study, the gas-liquid flow law of horizontal gas wells and wellhead drainage stability in different tubing depths were firstly studied. Then, the stability of gas drainage for different tubing depths was analyzed and confirmed. Given the disadvantages of the typical theory of critical gas flow, the mathematical model of different tubing depths for gas drainage is established for horizontal gas wells. The innovative model could take the energy of gas flow and liquid flow into account, and quantify the liquid volume which was removed. By verifying the model with the experiments, the result showed that the relative error of the model is generally less than 10%. It shows the research could provide a scientific basis for the analysis and liquid-carrying capacity for horizontal gas wells.
ARTICLE | doi:10.20944/preprints202010.0190.v1
Subject: Materials Science, Biomaterials Keywords: acid mine drainage; arsenate; arsenite; chromate; hemp cellulose; cellulose nanofibres; TEMPO-oxidation
Online: 9 October 2020 (09:02:44 CEST)
Mining-induced water contamination remains a significant concern in many regions of the world due to the high concentrations of toxic ions often associated with it. In this study, cellulose-supported ferrihydrite composites (CNF-Fe) were prepared by seeding of ferrihydrite nanoparticles on cellulose nanofibres (CNFs) and employed for the removal of As(III), As(V) and Cr(VI) from contaminated water. The adsorbent was characterized by electron microscopy, gas adsorption, point of zero charge (pHPZC), X-ray diffractometry (XRD), as well as infrared and Raman spectroscopy. Compared to parent CNFs, CNF-Fe adsorbents had lower crystallinity and a higher surface area: 218.76 m2 g-1. Further, with a pHPZC of 6.3, CNF-Fe was positively charged at low pH and suitable for adsorption of anions at acidic conditions characteristic of acid mine drainage. In single-ions solutions, the removal efficiency of CNF-Fe was in the order Cr(VI)>As(V)>As(III) (i.e. 0.15, 0.12 and 0.11 mg g-1 respectively). Adsorption kinetics followed the pseudo second-order model and isotherms were best fitted by the Freundlich, Dubinin-Radushkevich, and Temkin models. However, when CNF-Fe was applied to AMD-contaminated water (pH 2.7), Cr(VI) uptake decreased to ~39% which was likely due to competition from sulphate and selenium ions. Nevertheless, the adsorbent displayed regeneration capabilities with ~98% As and ~45% Cr desorbed after 24 hours of treatment. Together, these results suggest that cellulose supported ferrihydrite composites can be applied in treatment of mine drainage-contaminated water in conjunction with pre-treatments that limit SO42- and selenium concentrations.
ARTICLE | doi:10.20944/preprints202011.0680.v1
Subject: Engineering, Other Keywords: Urban Drainage Systems; Sustainable Stormwater Management; Costa Rica; Place-based research; Transition Stages
Online: 27 November 2020 (09:02:24 CET)
Green Infrastructure promotes the use of natural functions and processes as potential solutions to reduce negative effects derived from anthropocentric interventions such as urbanization. In cities of Latin America, for example, the need for more nature-sound infrastructure is evident due to its degree of urbanization and degradation of ecosystems, as well as the alteration of the local water cycle. In this study, an experimental approach for implementation of a prototype is presented. The experiment took place in a highly urbanized watershed located in the Metropolitan Area of Costa Rica. Initially, understanding the characteristics of the study area at different scales was achieved by applying the Urban Water System Transition Framework to identify the existing level of development of the urban water infrastructure, and potential future stages. Subsequently, preferences related to spatial locations and technologies were identified from different local decision-makers. Those insights were adopted to identify a potential area for implementation of the prototype. The experiment consisted on an adaptation of the local sewer to act as a temporal reservoir to reduce the effects derived from rapid generation of stormwater runoff. Unexpected events, not considered initially in the design, are reported in this study as a means to identify necessary adaptations of the methodology. Our study shows from an experimental learning-experience that the relation between different actors advocating for such technologies influences the implementation and operation of non-conventional technologies. Furthermore, the perception of security associated to green spaces was found as a key driver to increase the willingness of residents to modify their urban environments. In consequence, those aspects should be carefully considered as factors of designs of engineering elements when they are related to complex socio-ecological urban systems.
ARTICLE | doi:10.20944/preprints201811.0211.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: Trabectome Surgery, ab interno trabeculectomy, glaucoma drainage devices, Baerveldt Glaucoma Implantation, tube ligation
Online: 8 November 2018 (11:26:26 CET)
Purpose: To evaluate the efficacy and survival rates of trabectome-mediated ab interno trabeculectomy combined with non-fenestrated Baerveldt glaucoma implants (BT) in comparison to Baerveldt glaucoma implant alone (B).Method: A total of 175 eyes undergoing primary glaucoma surgery (60 eyes BT and 115 B) were enrolled in this retrospective comparative case series. Participants were identified using the procedural terminology codes. Groups were then matched using Coarsened Exact Matching (51 eyes in each group). The primary outcome measure was surgical success, defined as 5 mmHg < IOP ≤ 21 mmHg, and IOP reduction ≥ 20% from baseline, and no reoperation for glaucoma. Secondary outcome measures were intraocular pressure, the number of glaucoma medications, and best corrected visual acuity (BCVA).Results: The cumulative probability of success at one year was 61% in BT, and 50% in B. IOP decreased significantly from 23.5±2.4 mmHg at baseline to 14.1±2.7 mmHg at the final follow up in BT (P= 0.001). The corresponding numbers for B were 23.2± 2.0 and 13.9± 1.6, respectively (P= 0.001). There was no significant difference in IOP at the final follow-up (P=0.56). The number of medications at baseline was 2.3±0.3 in both groups. However, BT needed significantly fewer drops at all postoperative time intervals and used 1.1±0.3 (BT) and 2.0±0.4 eye drops (B) at the final follow-up visit (P= 0.004). No dangerous hypotony or hypertension occurred in BT.Conclusion: Similar rates of success and IOP reduction were observed in BT and B. BT needed significantly fewer glaucoma medications. Tube fenestration was not necessary in BT resulting in less postoperative hypotony and hypertension.
Subject: Engineering, General Engineering Keywords: mine rock drainage; sulfide oxidation; neutralization by silicates; secondary iron minerals; toxic element scavenging
Online: 15 October 2021 (12:22:41 CEST)
Mine waste rock and drainage pose lasting environmental, social, and economic threats to the mining industry, regulatory agencies, and society as a whole. Mine drainage can be alkaline, neutral, moderately or extremely acidic and contains significant levels of sulfate, dissolved iron, and frequently a variety of heavy metals and metalloids, such as cadmium, lead, arsenic, and selenium. In acid neutralization by carbonate and silicate minerals, a range of secondary minerals can form and possibly scavenge these potentially harmful elements. Apart from the extensively-studied microbial-facilitated sulfide oxidation, the diverse microbial communities present in mine rock and drainage may also participate in the formation, dissolution, and transformation of secondary minerals influencing the mobilization of these metals and metalloids. This article reviews major microbial-mediated geochemical processes occurring in mine rock piles that affect drainage chemistry, with a focus on the role of microorganisms in the formation, dissolution and transformation of secondary minerals. Understanding this is crucial for developing biologically-based measures to deal with contaminant release at the source, i.e., source control.
ARTICLE | doi:10.20944/preprints202107.0115.v1
Subject: Biology, Anatomy & Morphology Keywords: Controlled drainage; Water content; Salinity (EC); Mineral nitrogen; Nitrogen loss; Yield of oilseed sunflower
Online: 5 July 2021 (16:06:58 CEST)
Controlled drainage (CD) is an important agricultural measure for maintaining soil moisture and nutrients, controlling groundwater level, and increasing crop yield. In arid regions, CD can be used to improve the water supply in agriculture and reduce environmental pollution. In this study, we investigated the effect of CD, including a drainage depth of 40 cm (CWT1) and 70 cm (CWT2) during the plant growth period, free drainage (FD), and open ditch drainage (OD) on the migration of water, nutrients, and salts in the soil; the dynamics of groundwater level; the loss of soil nitrogen; and the growth of oilseed sunflower plants. Compared with FD, CD increased the water and nutrient content in the soil, reduced nitrogen loss, and enhanced the ability of the soil to continuously supply nitrogen to the oilseed sunflower plants, which benefited plant growth at later growth stages and reduced environmental pollution. During the period between irrigation at the budding stage and harvest stage, the average soil water content in the 0–20 cm soil layer in CWT1 increased by 3.67%, 4.78%, and 0.55%, respectively, compared with that in CWT2, FD, and OD. The soil mineral content in CWT1 was 25.17%, 35.05%, and 17.78% higher than that in CWT2, FD, and OD, respectively, indicating that higher soil salinity occurred at the later stage of plant growth in CWT1, which actually had little effect on the plants due to their enhanced salt tolerance and increased need for water and nutrients at that stage. In addition, CD delayed the decline in groundwater level, which allowed the plants to use groundwater at later growth stages, and as a result the yield and water use efficiency were improved. CWT1 significantly increased oilseed sunflower yield by 4.52–11.14% and increased water use efficiency by 1.16–10.8%. Moreover, CWT1 also increased the survival rate of the oilseed sunflower plants by 2.62–2.92%, and the plants demonstrated good growth. Therefore, under CD conditions, plants used soil water and nitrogen more efficiently and, as a result, their productivity was increased, and the water quality was improved.
ARTICLE | doi:10.20944/preprints202008.0172.v2
Subject: Engineering, Automotive Engineering Keywords: Sustainable Urban Drainage Systems; green roofs; analytical probabilistic approach; pre-filling volume; vegetation survival
Online: 7 December 2020 (08:07:00 CET)
The implementation of green roofs as sustainable urban drainage systems provides benefits for stormwater control and the environment and is always more encouraged. In this paper, the estimation of the probability of vegetation survival without irrigation has been proposed as a guide to choose the proper values for the design parameters; in particular the growing medium thickness has been related to the average return interval of the water content at the end of the dry period. Moreover the study represents an improvement of the analytical probabilistic approach since a chain of consecutive rainfall events has been considered, in order to take into account the possibility that the storage capacity is not completely available at the beginning of each event because of the pre-filling from more than one previous rainfall as typically happens for green roofs. Finally, developed equations have been validated by means of their application to two case studies, respectively in northern and southern Italy.
ARTICLE | doi:10.20944/preprints201904.0275.v2
Subject: Earth Sciences, Environmental Sciences Keywords: flood; Geodesign; urban growth; development; land use/land cover; green infrastructure; drainage; stormwater; runoff; underground storage
Online: 28 April 2019 (10:35:14 CEST)
The consequences of growing urbanization can be perceived in multiple levels around the globe: overpopulated living conditions, water and air pollution, loss of open space, costly transportation infrastructure, food shortages, fires and floods. The Houston metropolitan area is an example of fast urban growth, with a population increase of more than sixteen percent in seven years, going from 5.8 million people in 2010 to 6.9 million in 2017 . By 2045, the robust growth of the region is projected to lead to the addition of approximately five hundred square miles of developed area, including an estimated six million parking spaces, seven hundred eighty million square feet of non-residential uses, and three and a half billion square feet of residential use . The accelerated development, in addition to physical features, geomorphic processes and human activities in the region are believed to have caused Houston to suffer through over fifty devastating floods since its settlement, despite some successful flood damage reduction projects. The present study focused on the potential outcomes of an increased use of green infrastructure in comparable urban areas, and its effects on flooding volume. Results from the research revealed that not only these measures would likely improve the performance of existing urban drainage systems and attenuate flood incidence in the area, but would also promote connectivity between areas otherwise detached or only accessible by car, improving walkability and incentivizing engagement in outdoor activities.
ARTICLE | doi:10.20944/preprints201806.0248.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: short tunnel small flap; glaucoma drainage device implantation; tube exposure; STSF; Ahmed glaucoma valve; AGV
Online: 15 June 2018 (09:40:16 CEST)
Purpose: To compare the efficacy and safety of graft-free short tunnel small flap (STSF) technique with that of scleral patch graft (SPG) in Ahmed glaucoma valve (AGV) implantation. Design: Randomized clinical trial. Participants: Eighty-eyes of eighty patients with medically uncontrolled glaucoma including 41 in STSF and 39 eyes in SPG. Methods: Patients were enrolled and assigned randomly to STSF or SPG. Main Outcome Measures: tube exposure, Intraocular pressure (IOP), number of glaucoma medications, best corrected visual acuity (BCVA), surgical complications, and success rate ( defined as intraocular pressure (IOP) >5 mmHg, ≤21 mmHg, and IOP reduction ≥20% from baseline at two consecutive visits after three months, no reoperation for glaucoma). Results: only one case in SPG developed tube exposure at 1-year follow-up. The cumulative probability of success during the first year of follow-up was 70% in the STSF and 65% in SPG (P = 0.36). IOP decreased significantly from 29.6 ± 8.6 mmHg at baseline to 16.4 ± 3.6 mmHg at the final follow-up in STSF (p = 0.001). The corresponding numbers for SPG were 30.9 ± 11.2 and 15.8 ± 4.7, respectively (p = 0.001). The final IOP was comparable between both groups (p = 0.65). Mean ± standard deviation of the number of glaucoma medications was 1.8 ± 0.9 in STSF and 1.6 ± 0.9 in SPG at final follow-up (P = 0.32). Postoperative complications developed in 8 patients (19%) in STSF and 9 patients (23%) in SPG (P = 0.81). Conclusions: STSF and SPG techniques had comparable complication rate at one-year follow-up. Both techniques were comparable in terms of success rate, postoperative IOP, and glaucoma medications.
ARTICLE | doi:10.20944/preprints202212.0452.v1
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: Extended lumbar drainage; Hydrocephalus; Idiopathic normal pressure hydrocephalus; neurodegenerative diseases; Qualitative neurocognitive tests; Quantitative neurocognitive tests
Online: 23 December 2022 (08:09:41 CET)
Background: Idiopathic normal pressure hydrocephalus is a syndrome with neuroradiological findings and clinical pattern characteristic but not specific for the pathology. Since the prevalence is growing due to the rapidly aging society, standardized and validated protocol for diagnosis is needed, also because this condition may mimic other disorders among elderly such as Parkinson's and Alzheimer's disease. Material and methods: We analysed data from 44 patients with suspect diagnosis of idiopathic normal pressure hydrocephalus with age > 60 years, clinical triad and neuroradiological pattern examined in our ward from November 2018 to November 2022. Neu-ropsychological assessment includes Mini Mental State Examination and Mental Deterioration Battery. Motor scores were collected from gait and balance tests. The evaluation was performed before and after an extended lumbar drainage last 48h. Patients who has scores improvement after the extended lumbar drainage, undergo ventriculoperitoneal shunt with a programmable valve. Results: All patients undergo neuropsychological assessment and motor tests, only 2 patients were unable to perform motor tests because bedridden. 16 patients showed no benefit from the tests, in 2 cases even a worsening of cognitive performance. 28 patients showed an improvement in their performances, but in most cases the improvement involved only the neuropsychological as-sessment. All patients underwent ventriculoperitoneal shunt have had a typical answers pattern in Mental Deterioration Battery test. We performed 9 ventriculoperitoneal shunt and 1 ventricu-lo-atrial shunt. Conclusions: Qualitative neurocognitive tests come out to be more sensitive compared to quantitative neurocognitive tests in identifying patients with suspected idiopathic normal pressure hydrocephalus benefiting from extended lumbar drainage test and then un-derwent surgical treatment. This could be considered a valid screening in elderly patients with suspected idiopathic normal pressure hydrocephalus in order to minimize the number of invasive procedures. More studies are necessary to validate this tool.
ARTICLE | doi:10.20944/preprints202006.0127.v1
Subject: Earth Sciences, Geophysics Keywords: frequency-domain; ground penetrating radar; electromagnetic induction; penetration depth; inversion; non-destructive techniques; agricultural drainage systems
Online: 10 June 2020 (05:39:04 CEST)
Subsurface drainage systems remove excess water from the soil profile thereby improving crop yields in poorly drained farmland. Knowledge of the position of the buried drain lines is important: 1) to improve understanding of leaching and offsite release of nutrients and pesticides, and 2) for the installation of a new set of drain lines between the old ones for enhanced soil water removal efficiency. Traditional methods of drainage mapping involve the use of tile probes and trenching equipment. While these can be effective, they are also time-consuming, labor-intensive, and invasive, thereby entailing an inherent risk of damaging the drainpipes. Non-invasive geophysical soil sensors provide a potential alternative solution. Previous research has focused on the use of time-domain ground penetrating radar (GPR), with variable success depending on local soil and hydrological conditions and the central frequency of the specific equipment employed. The objectives of this study were 1) to test the use of a stepped-frequency continuous wave (SFCW) 3D-GPR (GeoScope Mk IV 3D-Radar with DXG1820 antenna array) for subsurface drainage mapping, and 2) to evaluate the performance of a 3D-GPR with the use of a single-frequency multi-receiver electromagnetic induction (EMI) sensor (DUALEM) in-combination. The 3D-GPR system offers more flexibility for application to different (sub)surface conditions due to the coverage of wide frequency bandwidth. The EMI sensor simultaneously provides information about the apparent electrical conductivity (ECa) for different soil volumes, corresponding to different depths. This sensor combination was evaluated on twelve different study sites with various soil types with textures ranging from sand to clay till. While the 3-D GPR showed a high success rate in finding the drainpipes at five sites (sandy, sandy loam, loamy sand, and organic topsoils), the results at the other seven sites were less successful due to limited penetration depth (PD) of the 3D-GPR signal. The results suggest that the electrical conductivity estimates produced by the inversion of ECa data measured by the DUALEM sensor could be a useful proxy to explain the success achieved by the 3D-GPR in finding the drain lines. The high attenuation of electromagnetic waves in highly conductive media limiting the PD of the 3D-GPR can explain the findings obtained in this research.
ARTICLE | doi:10.20944/preprints202106.0025.v1
Subject: Engineering, Automotive Engineering Keywords: Adequate drainage structures; Rainfall IDF Curve relationship; predicted peak rate of runoff (Qlogy); Gumbel’s Extreme Value Distribution Method.
Online: 1 June 2021 (11:14:54 CEST)
Due to the increase in the emission of greenhouse gases, the hydrologic cycle is being altered on the daily basis. This has affected the variations in relations of intensity, duration, and frequency of rainfall events. Intensity Duration Frequency (IDF) curves describe the relationship between rainfall intensity, rainfall duration and return period. IDF curves are one of the most often applied implements in water resource engineering, in areas such as for operating, planning and designing of water resource projects, or for numerous engineering projects aimed at controlling floods. In particular, IDF curves for precipitation answer problems of improper drainage systems or conditions and extreme characters of precipitation which are the main cause of floods in Nyabugogo catchment. This study aims to establish Rainfall IDF empirical equations, curves and hydrological discharge (predicted peak rate of runoff (Qlogy)) equations for eight Districts that will be used for designing an appropriate and sustainable hydraulic structures for controlling flood to reduce potential loss of human and aquatic life, degradation of water, air and soil quality and property damage and economic lessen caused by flood in Nyabugogo catchment. However Goodness of Fit tests revealed that Gumbel’s Extreme-Value Distribution method appears to have the most appropriate fit compared with Pearson type III distribution for validating the Intensity-Duration-Frequency curves and equations through the use of daily annual for each meteorological station. The findings of the study show that the intensity of rainfall increases with a decrease in rainfall duration. Additionally, a rainfall of every known duration will have a higher intensity if its return period is high, while the predicted peak rate of runoff (Qlogy) increases also with an increase in the intensity of rainfall.
TECHNICAL NOTE | doi:10.20944/preprints201811.0259.v1
Subject: Engineering, Civil Engineering Keywords: risk management; deterministic; probabilistic; engineering cost estimating; uncertainty; cost estimating methods; urban drainage infrastructure; Capital Improvement (CIP) Programs
Online: 12 November 2018 (04:27:22 CET)
Accurate and reliable project cost estimates are fundamental to achieve successful municipal capital improvement (CIP) programs. Engineering cost estimates typically represent critical information for key decision makers to authorize and efficiently allocate the necessary funds for construction, budgeting, to generate a request for proposals, contract negotiations, scheduling, etc. for these reasons, cost estimators are using different estimating methods and approaches that allow for required levels of accuracy. As the project’s scope becomes more detailed and the potential risks are identified and/or the project design stage progresses these cost estimates are revised and updated. In this paper, the most common project cost estimation methods and approaches were collected and categorized into two main groups of (1) probabilistic and (2) deterministic methods. Under these groups overall ten different methods were identified and discussed addressing their requirements, advantages, and shortcomings, including the potential risk that can positively or negatively affect the project’s cost outcome. This paper will be a good resource for professionals who are in budget development and/or are seeking to a better understanding of different methods in determining an appropriate base cost margin and produce a meaningful and reliable project cost estimate.
ARTICLE | doi:10.20944/preprints201905.0382.v1
Subject: Engineering, Other Keywords: supervised machine learning; flood inundation mapping; high-resolution; synthetic aperture radar; height above nearest drainage; sentinel-1; inundated vegetation
Online: 31 May 2019 (08:48:14 CEST)
Floods are one of the most wide-spread, frequent, and devastating natural disasters that continue to increase in frequency and intensity. Remote sensing, specifically synthetic aperture radar (SAR), has been widely used to detect surface water inundation to provide retrospective and near-real time (NRT) information due to its high-spatial resolution, self-illumination, and low atmospheric attenuation. However, the efficacy of flood inundation mapping with SAR is susceptible to reflections and scattering from a variety of factors including dense vegetation and urban areas. In this study, the topographic dataset height above nearest drainage (HAND) was investigated as a potential supplement to Sentinel-1A C-Band SAR along with supervised machine learning to improve the detection of inundation in heterogeneous areas. Three machine learning classifiers were trained on two sets of features SAR only (VV & VH) and VV, VH & HAND to map inundated areas. Three study sites along the Neuse River in North Carolina, USA during the record flood of Hurricane Matthew in October 2016 were selected. The binary classification analysis (inundated as positive vs. non-inundated as negative) revealed significant improvements when incorporating HAND in several metrics including classification accuracy (ACC) (+37.1%), true positive rate (TPR) (+51.2%), and negative predictive value (NPV) (+23.7%), A marginal improvement of +1.4% was seen for positive predictive value (PPV), but true negative rate (TNR) fell -15.1%. By incorporating HAND, a significant number of areas with high SAR backscatter but low HAND values were detected as inundated which increased true positives. This in turn also increased the false positives detected but to a lesser extent as evident in the metrics. This study demonstrates that HAND could be considered a valuable feature to enhance SAR flood inundation mapping especially in areas with heterogeneous land covers with dense vegetation that interfere with SAR.
REVIEW | doi:10.20944/preprints202204.0166.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: acute kidney injury; intra-abdominal pressure; oxidative stress; renal cortical blood flow; renal medullar blood flow; renal lymphatic drainage; venous congestion
Online: 18 April 2022 (10:45:36 CEST)
Acute kidney injury (AKI), especially if recurring represents a risk factor for future chronic kidney disease. In intensive care units, increased intraabdominal pressure is well-recognized as a significant contributor of AKI. However, the importance of transiently increased intra-abdominal pressures procedures is less commonly appreciated during laparoscopic surgery, the use of which has rapidly increased over the last few decades. Unlike the well-known autoregulation of the renal cortical circulation, medulla perfusion is modulated via partially independent regulatory mechanisms and strongly impacted by changes in venous and lymphatic pressures. In our review paper, we will provide a comprehensive overview of this evolving topic, covering a broad range from basic pathophysiology up to and including current clinical relevance. Key regulators of oxidative stress such as ischemia-reperfusion injury, the activation of inflammatory response and humoral changes interacting with procedural pneumoperitoneum formation and AKI risk will be recounted. Moreover, we present an in-depth review of the interaction of pneumoperitoneum formation with general anesthetic agents and animal models of congestive heart failure. A better understanding of the relationship between pneumoperitoneum formation and renal perfusion will support basic and clinical research, leading to improved clinical care and collaboration among specialists.
ARTICLE | doi:10.20944/preprints202009.0708.v1
Subject: Materials Science, Biomaterials Keywords: Cellulose cationisation; Chromium(VI); acid mine drainage; hemp cellulose; glycidyltrimethylammonium chloride; 3-chloro-2-hydroxypropyl trimethyl ammonium chloride; quaternary ammonium salts
Online: 29 September 2020 (12:44:08 CEST)
Cationised hemp cellulose was prepared by etherification with two quaternary ammonium salts: 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTAC) and glycidyltrimethylammonium chloride (GTMAC) and examined for (i) the efficiency of Cr(VI) removal under acid mine-drainage (AMD) conditions, and (ii) antibacterial activity. Adsorbents were characterised by electron microscopy, Fourier transform infrared (FTIR), CP-MAS 13C nuclear magnetic resonance (NMR) spectroscopy, elemental composition and surface charge. FTIR and solid state 13C NMR confirmed the introduction of quaternary ammonium moieties on cellulose. 13C NMR also showed that cationisation decreased the degree of crystallisation and lateral dimensions of cellulose fibrils. Nevertheless, 47 % - 72% of Cr(VI) ions were removed from solutions at pH 4, by 0.1 g of CHPTAC and GTMAC-cationised cellulose, respectively. Adsorption kinetics followed the pseudo-second order model and isotherms were best described by the Freundlich and Dubinin-Radushkevich models. When GTMAC-modified cellulose was applied to AMD contaminated water (pH 2.7), however, Cr(VI) uptake removal decreased to 22% likely due to competition from Al and Fe ions. Nevertheless, cationised materials displayed considerable antibacterial effects, reducing the viability of Escherichia coli by up to 45 % after just 3 hours of exposure. Together, these results suggest that cationised cellulose can be applied in the treatment of Cr(VI)-contaminated mine water particularly if pre-treatments to reduce Fe and Al concentrations are applied.
ARTICLE | doi:10.3390/sci2020046
Subject: Keywords: portable X-ray fluorescence spectrometer (pXRF); Potential Toxic Elements (PTE); lead (Pb), zinc (Zn); copper (Cu); topsoil; sustainable urban drainage systems; SuDS; LID; BMPs; WSUD; GI; SCMs
Online: 13 June 2020 (00:00:00 CEST)
Sustainable urban drainage systems (SuDS) such as swales are designed to collect, store and infiltrate a large amount of surface runoff water during heavy rainfall. Stormwater is known to transport pollutants, such as particle-bound Potential Toxic Elements (PTE), which are known to often accumulate in the topsoil. A portable XRF instrument (pXRF) is used to provide in situ spatial characterization of soil pollutants, specifically lead (Pb), zink (Zn) and copper (Cu). The method uses pXRF measurements of PTE along profiles with set intervals (1 meter) to cover the swale with cross-sections, across the inlet, the deepest point and the outlet. Soil samples are collected, and the In-Situ measurements are verified by the results from laboratory analyses. Stormwater is here shown to be the transporting media for the pollutants, so it is of importance to investigate areas most prone to flooding and infiltration. This quick scan method is time and cost-efficient, easy to execute and the results are comparable to any known (inter)national threshold criteria for polluted soils. The results are of great importance for all stakeholders in cities that are involved in climate adaptation and implementing green infrastructure in urban areas. However, too little is still known about the long-term functioning of the soil-based SuDS facilities.
ARTICLE | doi:10.20944/preprints202205.0183.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Energy geostructure; ground source heat pump (GSHP); sustainable urban drainage system (SUDS); sector integration; 5th generation district heating and cooling; permeable asphalt; rainwater retardation; full-scale demonstration; numerical modelling; analytical modelling
Online: 13 May 2022 (08:06:39 CEST)
This paper proposes and demonstrates, in full scale, a novel type of energy geostructure (“the Climate Road”) that combines a ground source heat pump (GSHP) with a sustainable urban drainage system (SUDS) by utilizing the gravel roadbed simultaneously as energy source and rainwater retarding basin. The Climate Road measures 50m x 8m x 1m (length, width, depth) and has 800 m of geothermal piping embedded in the roadbed, serving as the heat collector for a GSHP that supplies a nearby kindergarten with domestic hot water and space heating. Model analysis of operational data from 2018-2021 indicates sustainable annual heat production levels around 0.6 MWh per meter road, with a COP of 2.9-3.1. The continued infiltration of rainwater to the roadbed increases the amount of extractable heat by an estimated 17% compared to the case of zero infiltration. Using the developed model for scenario analysis we find that draining rainwater from three single family houses and storing 30% of the annual heating consumption in the roadbed, increases the predicted extractable energy by 56% compared to zero infiltration with no seasonal energy storage. The Climate Road is capable of supplying three single family houses with heating, cooling and rainwater management year-round.
REVIEW | doi:10.20944/preprints202008.0696.v1
Subject: Life Sciences, Virology Keywords: COVID-19; SARS-CoV-2; neurotropic virus; Blood-nervous system barrier; bloodcerebrospinal-fluid-barrier; blood-brain-barrier; blood-nerve barrier; olfactory route; Lymphatic brain drainage route; Peripheral nerve or neuronal retrograde route; Macrophage/monocytes cargo route; Double membrane vesicles cargo route; nicotinic acetylcholine receptor
Online: 31 August 2020 (04:43:34 CEST)
Without protective and/or therapeutic agents the SARS-CoV-2 infection known as coronavirus disease 2019 (COVID-19) is quickly spreading worldwide. It has surprising transmissibility potential, since it could infect all ages, gender, and human sectors. It attacks respiratory, gastrointestinal, urinary, hepatic, and endovascular systems and can reach the peripheral nervous system (PNS) and central nervous system (CNS) through known and unknown mechanisms. The reports on the neurological manifestations and complications of the SARS-CoV-2 infection are increasing exponentially. Herein, we enumerate seven candidate routes, which the mature or immature SARS-CoV-2 components could use to reach the CNS and PNS, utilizing the within-body crosstalk between organs. The majority of SARS-CoV-2 infected patients suffer from some neurological manifestations (e.g., confusion, anosmia, and ageusia). It seems that although the mature virus did not reach the CNS or PNS of the majority of patients, its unassembled components and/or the accompanying immune-mediated responses may be responsible for the observed neurological symptoms. The viral particles and/or its components have been specifically documented in endothelial cells of lung, kidney, skin, and CNS. This means that the blood-endothelial-barrier may be considered as the main route for SARS-CoV-2 entry into the nervous system, with the barrier disruption being more logical than barrier permeability, as evidenced by postmortem analyses.