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The quantification of abiotic features is a process in Geodiversity focused studies to indicate priority areas for conservation. Although some quantification methods are in use, doubts remain as to their applicability, particularly the relationship between coefficients of geodiversity and rugosity. In this perspective, this study proposes to analyze this relationship through the geostatistical models of Local Moran's I and Geographically Weighted Regression (GWR), applied in sub-basins of one of the most important karstic regions in Brazil. To simulate the rugosity coefficient, the Global Relief Dissection Index was used, which consists of a combination of morphometric indices that enable the estimation of a given region's power of dissection. The application of Local Moran's I showed geodiversity and relief dissection potential behavior patterns, demonstrating that the variables have spatial dependence and are correlated at certain points. The application of GWR was successful, although the model was not able to explain the regional relationship between the coefficients of geodiversity and relief dissection. Nevertheless, it enabled local analysis of different behaviors through the spatialization of local R2 and residuals. It can be inferred that there are other variables that interfere in the local geodiversity, especially, for being a geosystem with characteristics specific. [ABSTRACT FROM AUTHOR]

Using the river, canal, and flume data, it is found that the role played by the seasonal variation in the Manning rugosity coefficient, n, equalizes the sediment transporting capacity with sediment supply in the dune bed-form regime. Aggradation/degradation in a sand-bed river is thus avoided on a seasonal basis. A relation between the dimensionless rugosity coefficient and the dimensionless ratio of stream power to sediment concentration exists in sand-bed rivers for any specific gauge height. Once field measurements of the sediment transport rate are made and such a relationship is worked out, thereafter, it may be possible to estimate the sediment concentration for each observed flow discharge merely by applying this relationship adopting the data of velocity, depth, slope, and bed material size which are routinely observed at a stream-gauging site. [ABSTRACT FROM AUTHOR]

Standing flows in natural channels often cause phenomena that can be very serious, such as flooding, deformation of channel geometry, and destruction of infrastructure (dams, bridges, and culverts). This study focuses on the computation of gradually varying permanent flows (backwater curves) by two methods: direct integration (Chow) and successive approximation (depth variation). To solve the system of equations governing the problem of gradually varying one-dimensional stationary flows at a free surface, a large amount of data should be taken into account, namely, the flow rate, the water head, the mean flow velocity, the rugosity, and the slope. These parameters are very important, as they cause nonlinear behavior, making the problem and its mathematical solution complex. Digitizing these parameters can help to determine and visualize the longitudinal profile of the water line for known flow rates. This study aimed to: (1) determine the influence of rugosity on gradually varying steady flows and the overclassification of eddy curves in a prismatic channel, (2) study the effect of geometric shape on these flows, and (3) investigate and compare the effects of the calculation methods. The results reveal the great influence of rugosity on gradually varying permanent flows for four selected geometric shapes of the channel, as it has a direct influence on the normal depth and the critical slope. Each time the resistance of the bottom to the flow increases, these results increase. The influence of the geometric shape on these flows is less significant. The comparative study showed a difference between the results obtained. [ABSTRACT FROM AUTHOR]

Transports of people and goods contribute to the ongoing 6th mass extinction of species. They impact species viability by reducing the availability of suitable habitat, by limiting connectivity between suitable patches, and by increasing direct mortality due to collisions with vehicles. Not only does it represent a threat for some species conservation capabilities, but animal vehicle collisions (AVC) is also a threat for human safety and security in transport and has a massive cost for transport infrastructure (TI) managers and users. Using the opportunities offered by the increasing number of sensors embedded into TI and the development of their digital twins, we developed a framework aiming at managing AVC by mapping the collision risk between trains and ungulates (roe deer and wild boar) thanks to the deployment of a camera trap network. The proposed framework uses population dynamic simulations to identify collision hotspots and assist with the design of sensors deployment. Once sensors are deployed, the data collected, here photos, are processed through deep learning to detect and identify species at the TI vicinity. Then, the processed data are fed to an abundance model able to map species relative abundance around the TI as a proxy of the collision risk. We implement the framework on an actual section of railway in south-western France benefiting from a mitigation and monitoring strategy. The implementation thus highlighted the technical and fundamental requirements to effectively mainstream biodiversity concerns in the TI digital twins. This would contribute to the AVC management in autonomous vehicles thanks to connected TI. [ABSTRACT FROM AUTHOR]

Treatment wetlands are recognized as an effective technology for mitigating the impacts of urban runoff. However, there is no consensus on the design guidelines, and the effects of some design features, such as the underdrain system, remain unexplored. A simple analog model has been developed to mimic the underdrain network (when operating at saturation) and to evaluate the spatial heterogeneity of the flow entering it. The model has been applied to a treatment wetland in the Paris area and shows that the underdrain network was largely undersized, likely causing an uneven distribution of infiltrating flow along the length of the treatment wetland. It was also shown that this analog model can be used for optimization purposes and that it is important to use conservative values of the rugosity coefficient when designing an underdrain network. HIGHLIGHTS A brand-new analog model has been developed to mimic the hydraulic functioning of the underdrain.; Inflows into the underdrain decrease with the distance to the outlet.; Undersized underdrains can create uneven distribution of the percolating flow along the length of a treatment wetland (TW).; The analog model allows optimizing the design of underdrains for TWs with a saturated layer at the bottom.;

The initial step of biofilm formation is bacteria attachment to biotic or abiotic surfaces and other bacteria through intra or interspecies interactions. Adhesion can be influenced by physicochemical conditions of the environment, such as iron. There is no available mathematical model of bacterial attachment giving realistic initiation rather than random adhesion. We describe a simple stochastic attachment model, from the simplest case in two dimensions with one bacterial species attaching on a homogeneous flat surface to more complex situations, with either several bacterial species, inhomogeneous or non-flat surfaces, or in three dimensions. The model depends on attachment probabilities (on the surface, laterally, or vertically on bacteria). Effects of each of these parameters were analyzed. This mathematical model is then applied to experimental oral microcolonies of Porphyromonas gingivalis, Streptococcus gordonii, and Treponema denticola, either as mono-, two, or three species, under different iron concentrations. The model allows to characterize the adhesion of three bacterial species and explore the effect of iron on attachment. This model appears as a powerful tool for initial attachment analysis of bacterial species. It will enable further modeling of biofilm formation in later steps with biofilm initialization more relevant to real-life subgingival biofilms. [ABSTRACT FROM AUTHOR]

The origin of pisoids in a diversity of environments has been recently discussed. While traditionally considered physico‐chemical sedimentary products developed in turbulent environments, or even grown in situ, new results show that microbes may influence their development. In the Terma Los Hornos travertine system, two types of actively forming pisoids were recognized: (i) laminated pisoids with a concentrically laminated crust surrounding a nucleus; and (ii) dendriform radial pisoids with no distinct nucleus. Laminated pisoids form in turbulent pools at the base of waterfalls, while dendritic pisoids develop within small depressions between terracettes, and they can occur superposed as a result of episodic transport and recycling within the travertine system (for example, dendritic textures as nucleus of laminated pisoids). The laminated pisoids are characterized by laterally constant laminae thickness with high inheritance and low amounts of randomly distributed organic matter and microbial remains, suggesting a predominantly abiogenic origin. In contrast, the dendritic pisoids exhibit an intimate relationship with diatoms and filamentous bacteria suggesting a stronger biotic influence in their formation. Thus, both abiogenic and biogenic carbonate structures can coexist in the same hydrothermal system. Pisoids found in the stratigraphic record of Terma Los Hornos allowed to test the preservation potential of the primary signals and reconstructing early diagenetic overprints. [ABSTRACT FROM AUTHOR]

Despite the high historical losses attributed to flood events, Canadian flood mitigation efforts have been hindered by a dearth of current, accessible flood extent/risk models and maps. Such resources often entail large datasets and high computational requirements. This study presents a novel, computationally efficient flood inundation modeling framework ("InundatEd") using the height above nearest drainage (HAND)-based solution for Manning's equation, implemented in a big-data discrete global grid system (DGGS)-based architecture with a web-GIS (Geographic Information Systems) platform. Specifically, this study aimed to develop, present, and validate InundatEd through binary classification comparisons to recently observed flood events. The framework is divided into multiple swappable modules including GIS pre-processing; regional regression; inundation models; and web-GIS visualization. Extent testing and processing speed results indicate the value of a DGGS-based architecture alongside a simple conceptual inundation model and a dynamic user interface. [ABSTRACT FROM AUTHOR]

Water distribution networks (WDNs) are the main component of industrial and urban water distribution systems and are currently formed by pipes, nodes and loops. In this article, a deterministic mathematical programming approach is proposed, aiming to minimize the cost of looped WDNs, considering known pipe lengths and a discrete set of commercially available diameters. The optimization model constraints are mass balances in nodes, energy balances in loops and hydraulic equations, in such a way that no additional software is needed to find the appropriate pressure drops and water velocities. Generalized disjunctive programming is used to reformulate the discrete optimization problem to a mixed-integer nonlinear programming (MINLP) problem. The GAMS (General Algebraic Modeling System) environment is used to solve the problem. Four cases are studied to test the applicability of the model and the results show compatibility with the literature. [ABSTRACT FROM AUTHOR]

Copyright of Farmacia is the property of Societatea de Stiinte Farmaceutice Romania and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays most of the desilting basins constructed or proposed in hydro power projects are modified in shape to increase desilting efficiency and structural stability; can be lined or unlined depending upon geological conditions faced. The desilting basin is an arrangement having increased cross-sectional area to reduce velocity of flow to such an extent that sediment particles settle within it efficiently. Most of the present day desilting basins are designed as wide rectangular basins; however, in general width/depth ratio is not too high nor is the desilting basin completely rectangular in shape. The purpose of this paper is to modify existing empirical and analytical methods used for desilting efficiency estimation for modified shaped desilting basins using hydraulic radius parameter, actual area consideration that will be applicable to both lined and unlined desilting chambers using friction factor parameter and to address limitations from applicability point of view. [ABSTRACT FROM AUTHOR]

At times, various analytical and empirical approaches used to estimate the initial sizing of a desilting basin in a hydropower project would give very different results and the designer has to take a call judiciously. The purpose of this study is to develop a monograph based on Teaching-Learning-Based Optimization and Gravitational Search algorithm for a practical range of depth of desilting basins. The parameters commonly used in hydropower projects for estimation of desilting basins sizing and its efficiency are used in this study. The outcome is further verified using a list of mega hydropower projects. This study will be useful in fixing the best optimized dimension of desilting basins. [ABSTRACT FROM AUTHOR]

Copyright of Italian Journal of Engineering Geology & Environment is the property of Sapienza Universita di Roma and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Traditionally, the analysis of cables under the influence of wind is performed using an equivalent static analysis. However, the occurrence of countless accidents in structural systems where cables are involved, even in cases where the project speed limit has not been reached, indicates that the collapse may have been caused by dynamic actions or by underestimated values of wind speed. The aim of this article is to introduce a dynamic analysis methodology for cables under the influence of wind and its forces. The validation procedure proposed is performed through a comparison among the results obtained, results from other researches, and wind tunnel experimental results. In parallel, comparison of the results is obtained in both static and dynamic analysis. [ABSTRACT FROM AUTHOR]

Copyright of Agrociencia is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

the morphometric characteristics of microbasin Stream Limo. There was a visited in the studyarea, being applied questionnaire in a sample of local population. The social deteriorationcalculated (S) was of 34,5%, evidencing that the producers have urban origin and low instruction.For the economical factor (E) 39,1% were gotten and can be noticed the financial difficulty ofthe agricultural producer that has income up to five minimum wages, therefore its productivityare low. The technological factor (T) it was obtained 26,5%, index still low the range, that is the morphometric characteristics of microbasin Stream Limo. There was a visited in the studyarea, being applied questionnaire in a sample of local population. The social deteriorationcalculated (S) was of 34,5%, evidencing that the producers have urban origin and low instruction.For the economical factor (E) 39,1% were gotten and can be noticed the financial difficulty ofthe agricultural producer that has income up to five minimum wages, therefore its productivityare low. The technological factor (T) it was obtained 26,5%, index still low the range, that isthe morphometric characteristics of microbasin Stream Limo. There was a visited in the studyarea, being applied questionnaire in a sample of local population. The social deteriorationcalculated (S) was of 34,5%, evidencing that the producers have urban origin and low instruction.For the economical factor (E) 39,1% were gotten and can be noticed the financial difficulty ofthe agricultural producer that has income up to five minimum wages, therefore its productivityare low. The technological factor (T) it was obtained 26,5%, index still low the range, that isthe morphometric characteristics of microbasin Stream Limo. There was a visited in the studyarea, being applied questionnaire in a sample of local population. The social deteriorationcalculated (S) was of 34,5%, evidencing that the producers have urban origin and low instruction.For the economical factor (E) 39,1% were gotten and can be noticed the financial difficulty ofthe agricultural producer that has income up to five minimum wages, therefore its productivityare low. The technological factor (T) it was obtained 26,5%, index still low the range, that isrelated to the agricultural exploration in the area, and it misses the technical assistance. Forthe socioeconomic factor (S+E+T) 34,3% were gotten, low value, demonstrating the limitationon the conditions of the producer life. For the environmental factor it was obtained 25,0%,value also low, however it evidences that ¼ of the ambient already is spoiled. Although thebiggest indices of deterioration to be lesser that 50.0%, measured mitigate need if implanted,therefore this process tends to evolve. Through the morphometric analyses it is observed thatthe stream is small, the basin it possess to circulate format, it has low draining, sinuosity anddeclivity, being an inclined area the floods, however the rugosity coefficient discloses that themicrobasin possess aptitude for agriculture.

Reef islands are low-lying accumulations of unconsolidated sediment formed from the skeletal remains of carbonate-producing reef organisms and are therefore perceived as highly vulnerable to environmental change. However, basic elements of island composition are not well described and given their high inter- and intra-basinal variability a better understanding of reef and island sedimentary environments (and the connections between them) are needed to predict future morphological response. Here, we use detailed ecological and sedimentological datasets to delineate key sediment production zones and biosedimentary depositional facies across the surface of Vabbinfaru platform, Maldives. Field measurements of platform hydrodynamics are applied to sedimentary deposits to determine the potential mobility of grains and identify transport pathways. Carbonate production was dominated by coral framework (mean: 52%) within a narrow zone on the outer reef rim (22% of platform area) resulting in coral-rich detrital sediments (reef: 51%, island: 64%) that closely resemble living assemblages. The net transfer of sediment occurred lagoonward by wave-driven processes leading to a decrease in grain size towards the island ( R2 = 0.502) which acts as a major control on depositional facies development within the lagoon. Island sediments were distinct from reefal deposits, comprising a restricted suite of durable sands (mean: 1.34ϕ) throughout long-term development. Our findings suggest that the production, breakdown and redistribution of coral-derived sediment by platform currents is fundamental to future island stability at Vabbinfaru, and although alterations away from current ecological states may reduce sediment supply, the timescales over which island morphological response will occur depends upon phase lags between initial coral mortality and the conversion of this material into island-grade sand. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The analysis of flood exposure at a national scale for the French insurance market must combine the generation of a probabilistic event set of all possible (but which have not yet occurred) flood situations with hazard and damage modeling. In this study, hazard and damage models are calibrated on a 1995-2010 historical event set, both for hazard results (river flow, flooded areas) and loss estimations. Thus, uncertainties in the deterministic estimation of a single event loss are known before simulating a probabilistic event set. To take into account at least 90 % of the insured flood losses, the probabilistic event set must combine the river overflow (small and large catchments) with the surface runoff, due to heavy rainfall, on the slopes of the watershed. Indeed, internal studies of the CCR (Caisse Centrale de Reassurance) claim database have shown that approximately 45 % of the insured flood losses are located inside the floodplains and 45 % outside. Another 10 % is due to sea surge floods and groundwater rise. In this approach, two independent probabilistic methods are combined to create a single flood loss distribution: a generation of fictive river flows based on the historical records of the river gauge network and a generation of fictive rain fields on small catchments, calibrated on the 1958-2010 Météo-France rain database SAFRAN. All the events in the probabilistic event sets are simulated with the deterministic model. This hazard and damage distribution is used to simulate the flood losses at the national scale for an insurance company (Macif) and to generate flood areas associated with hazard return periods. The flood maps concern river overflow and surface water runoff. Validation of these maps is conducted by comparison with the address located claim data on a small catchment (downstream Argens). [ABSTRACT FROM AUTHOR]

Runoff on impervious surfaces (roads, roofs, etc.) raises a number of environmental and road safety-related problems. The primary objective of this research effort is to improve our knowledge of the hydrological behaviour of impervious urban surfaces in order to better assess runoff on these surfaces and its subsequent consequences. This article will focus on two street stretches studied over a 38-month period. Measurements of rainfall and runoff discharge on these stretches have made it possible to estimate runoff losses as well as to constitute a database for modelling purposes. On the basis of these data, two models have been used, one simple the other more detailed and physically based. For both models, runoff discharges at a 3-min time step are well reproduced, although runoff coefficients and runoff losses are still poorly estimated. Detailed analyses of experimental data and model output, however, indicate that runoff losses could be quite high on such 'impervious surfaces' (between 30 and 40% of total rainfall, depending on the street stretch) and that these losses are mainly because of evaporation and infiltration inside the road structure. [ABSTRACT FROM AUTHOR]

Many neurotransmitters, such as γ-amino butyric acid (GABA), can act as chemical cues influencing settlement and metamorphosis in benthic marine invertebrates. This effect has been described especially in mollusks, such as mussels, clams, or haliotids. This study describes the first record of the effect of GABA on patellogastropod populations. Special attention was paid to the effect of the compound on recruitment processes. The experiment was carried out using 10 × 10 cm artificial limestone plates that were drilled into intertidal rocks at different inclinations, and periodically treated with a 1 mM GABA solution. A total of five limpet species was considered (four patellid limpet species and the pulmonate Siphonaria pectinata). Each individual recorded on the plates as well as within a 20 × 20 cm quadrant was measured, identified to species level, and its straight-line distance to the application point was registered. Treated surfaces were the first to possess both adults and recruits. Individuals also were found in a higher number around GABA-treated plates than around controls. The results indicated that the compound may not only enhance recruitment, but also might accelerate it. Recruits were located at higher distances from GABA treated plates than from control surfaces. This supports the hypothesis that this is the life history stage most sensitive to the compound. The behavior shown by the individuals belonging to the two endangered patellid species present in the study area ( Patella ferruginea and Cymbula nigra) also were analyzed. For the former, the results indicated that the use of GABA may have similar effects on recruitment similar to the presence of adult conspecifics. This is the first report of the effect of GABA on patellid limpet recruitment and population dynamics. Conservational implications of the results are discussed. [ABSTRACT FROM AUTHOR]

In this study, the adsorption behavior of natural bentonite with respect to Fe(III) and Ni(II) has been studied in order to consider its application to purity metal finishing wastewaters. During the adsorption process, batch technique is used, and the effects of pH, bentoite amount, temperature, heavy metal concentration, bentonite treatment (calcinations of natural bentonite at 700°C, washing by deionized water to remove the excess salt from bentonite surface), and agitation time on adsorption efficiency are studied. The washed and calcined bentonite samples were labeled by WB and CB, respectively. The pH-dependence of Fe(III) and Ni(II) sorption on the bentonite is significantly more noticeable, indicating a major contribution of surface complexation at the edge sites. It was determined that adsorption of Fe(III) and Ni(II) is well fitted by the second order reaction kinetic. Furthermore, the sorption rate of Fe(III) was higher than the sorption rate of Ni(II). Adsorption of Fe(III) and Ni(II) on NB appeared to follow Langmuir isotherm. In addition, calculated and experimental adsorbed amounts of Fe(III) by the unit NB mass are very higher than Ni(II). The paper also discusses the thermodynamic parameters of the adsorption (the Gibbs free energy, entropy, and enthalpy). Our results demonstrate that the adsorption process was spontaneous and endothermic under natural conditions. Also the adsorption capacity of bentonite for Fe(III) Ni(II) and increases with increased bentonite dose. According to the equilibrium studies, the selectivity sequence can be given as Fe(III) > Ni(II). The adsorbed amount of Fe(III) and Ni(II) on washed bentonite (WB) were very higher compared to NB and CB. Our results show that bentonite could especially WB be considered as a potential adsorbent for Fe(III) and Ni(II) removal from aqueous solutions. [ABSTRACT FROM AUTHOR]

In this paper, a review of the modern state of the river ice jamming numerical modeling is given. Descriptions and algorithms of mathematical models of ice jamming are presented. Questions related to the models practical implementation for the ice jamming forecasting are considered. [ABSTRACT FROM AUTHOR]

In this paper, we describe a simple technique for controlling the porosity of tungsten cathodes and replacing the barium compound impregnated matrix with a reservoir of barium producing compounds. Consequently, the cathode thus produced yields a uniform work function surface and significantly longer life than porous tungsten cathodes. The process uses existing sintering equipment and readily available, modestly priced materials. It is anticipated that successful development of this process will lead to less expensive, higher quality cathodes. [ABSTRACT FROM AUTHOR]

Coral reefs experienced the third global bleaching event in 2015–2016 due to high sea-surface temperature (SST) anomalies. Declines in net carbonate production associated with coral bleaching are implicated in reef structural collapse and cascading impacts for adjacent coral reef islands. We present the first carbonate budget study of a reef platform surface (reef crest and reef flat) in the southern Maldives and the first record of upper reef flat condition in the central Indian Ocean post the 2015–2016 coral bleaching event. Scleractinian corals were the primary carbonate producers, with live coral cover averaging between 11.1 ± 6.5 and 31.2 ± 21.8% and dominated by massive corals. Gross carbonate production rates averaged 5.9 ± 2.5 G (kg CaCO3 m2 yr−1). Bioerosion was estimated at 3.4 ± 0.4 G, resulting in an average net carbonate production rate of 2.5 ± 2.4 G. Comparison of results with a study of the fore-reef slope highlights major differences in post-bleaching carbonate budget state between the fore-reef slope and the reef platform surface. The positive reef flat carbonate budget is attributed to the persistence of massive corals (Porites spp. and Heliopora spp.) through the bleaching event. [ABSTRACT FROM AUTHOR]