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The purpose of this research is to investigate the antimicrobial activity of the microalgae Scenedesmus sp. and Spirulina platensis cultivated in BG-11 culture medium and the effluent of desalination facilities of Bandar Turkmen unit, Golestan province in inhibiting the growth and proliferation of gram-positive Staphylococcus aureus bacteria. And gram-negative Escherichia coli. Algae were extracted by water-alcohol method in proportion (500 cc of alcohol and 50 cc of distilled water) and determination of minimum inhibitory concentration (MIC) was checked by broth micro dilution method (96 plates) and with The amount of antibacterial activity grown in the water of their usual environment was compared. The results of the two mentioned bacteria in the presence of different concentrations of water-ethanol extract within 24 hours showed that in the extracted extract of the genus Scenedesmus sp. and Spirulina platensis cultivated in BG-11 culture medium and 50 and 100% dilutions of wastewater, against the bacteria There was no minimum inhibitory concentration (MIC) of Staphylococcus aureus and Escherichia coli during (24 hours). The extract of Scenedesmus sp. grown in BG-11 with a concentration of 25 and 50 mg/ml has a higher concentration of Escherichia coli than spirulina platensis in the early hours. As the concentration increases, the amount of bacteria decreases in the early hours. The extract of Spirulina platensis grown in BG-11 showed high control properties to Staphylococcus bacteria in the early hours compared to Scenedesmus sp. extract grown in 50% wastewater compared to spirulina platensis had the highest concentration of Escherichia coli bacteria in the final hours, so that it showed higher controlling properties than spirulina platensis against Escherichia coli. Also, in the extract of Scenedesmus sp. grown in 50% wastewater at concentrations of 25, 100 and 200 mg/ml in the last hours, the concentration of Staphylococcus bacteria is higher than the concentration of 50 mg/ml and in spirulina in the last hours It has had a steady trend. In both extracts grown in 100% wastewater, they showed the highest concentration of bacteria in all concentrations within 4 hours. Therefore, in all concentrations of the two extracts, they showed an increase in the concentration of Staphylococcus bacteria over time (2-4 hours). Therefore, spirulina cultivated in 100% wastewater had a stable trend in the final hours compared to Scenedesmus sp. and showed more controlling properties against staphylococcus. [ABSTRACT FROM AUTHOR]

In recent decades, the earth's surface data have been collected more efficiently using remote sensing, which needs drought indexes update. In this study, soil moisture (SM) data were collected from the surface layer of a high humidity climate in northern Iran using Soil Moisture Active Passive (SMAP) and field measurement. After analyzing the data, we found that the average RMSE between the field and SMAP measurement was 0.054 m 3 m 3 . Considering the same agricultural land use and the strong correlation of 0.92 between them, the validated SMAP data were used to propose an agricultural drought index. After data validation, the extreme learning machine (ELM) model was put to the test using sigmoid, triangular, sine, and hard-limit activation functions. Of all the activation functions tested, the model with the sigmoid activation function yielded the lowest amount of error and was therefore chosen. Five years of continuous daily SM as a target, five-year daily normalized difference vegetation index, land surface temperature, and precipitation were inputs to predict one-year daily SM time series in the humid climate. From 2021 to 2022, daily surface SM was predicted with the average RMSE = 0.03 m 3 m 3 compared to the SMAP data. Finally, a new regional agricultural drought index based on 4 years of SMAP and 1-year prediction of SMAP from 2022 to 2023 was proposed. Further investigation is needed to conclude that the application of the presented index is reliable in other climates. [ABSTRACT FROM AUTHOR]

This study aims to provide insights into groundwater stress and subsidence in the Varamin plains, located in central Iran. To achieve this, groundwater distributed modeling was simulated, and the groundwater stress index was evaluated accordingly. The area was divided into nine sections based on the intensity and spatial distribution of stresses and subsidence. The study conducted sensitivity analysis to reduce uncertainty, focusing on the importance of abstraction, recharge, and environmental flow at groundwater footprint and stress index equation. The impact of input variables on the groundwater stress index was evaluated using two methods of local and global sensitivity analysis, and the results were compared. A partial correlation criterion was also applied to measure the relationship between stress-dependent variables and three independent variables. The analysis revealed that the correlation analysis and global sensitivity analysis are consistent with each other and differ from the local sensitivity analysis. The abstraction based on global sensitivity analysis and correlation analysis has the greatest impact on stress, while a local sensitivity analysis showed that the reduction in recharge had the greatest effect. The study found that the impact of environmental flow requirements is negligible. Based on the results, the study presented different scenarios for reducing stresses in critical areas and proposed corresponding scenarios to reduce stress in the future management of the plain. A review of three different scenarios for the Varamin plain revealed that recharge is the most effective parameter that correlates with local sensitivity analysis. However, based on the results of the analysis of global sensitivity and correlation coefficient analysis, abstraction has the highest effectiveness. • The effect of recharge, abstraction and environmental flow was studied on GWSI. • Sensitivity analysis and management scenarios have been performed in this research. • Global sensitivity analysis indicates abstraction is the most effective variable. • Recharge has the greatest effect on GWSI based on local sensitivity analysis. • The artificial recharge is more effective to reduce stress in the aquifer. [ABSTRACT FROM AUTHOR]

Population growth and increasing demand for water have posed a significant challenge to access to safe water resources. Climate change and land use in the not-too-distant future add to the complexity of this challenge. Therefore, it is essential to achieve reliable methods for predicting changes in aquifer storage to plan for the sustainable use of groundwater resources. This study aimed to investigate the management, protection, and sustainable use of groundwater resources under climate change and land use change conditions. In this regard, groundwater supply and demand in one of the important plains in Iran (Hashtgerd plain) for 2020 as the base year was simulated to forecast the trends until 2050 by considering climate change and land use to develop management scenarios to adapt to these conditions using the WEAP model. First, climate change prediction was performed using the HadGEM2-ES model under two emission scenarios, RCP2.6, and RCP8.5, of the IPCC Fifth Assessment Report. The LARS-WG model was used to downscale the climatic data, while land use mapping was performed using Landsat satellite images of 1990, 2005, and 2020 in ENVI 5.3 software. Then, the Markov chain method implemented in TerrSet software was used to model land use change for 2050. The effect of climate change and land use on the decrease of groundwater level was then simulated using the MODFLOW model for the period 2020–2050. In order to manage the water allocation in the area, the information obtained from MODFLOW was transferred to the WEAP model using Link Kitchen interface software. The effects of various management scenarios such as increasing irrigation efficiency, reducing the loss of drinking water distribution networks, and allocating water from the transmission line were evaluated on the adaptation to climate change and land use for a 30-year period. The results showed that with the simultaneous consideration of climate change and land use in the most critical state, the average drop in groundwater level would reach 58 m during the study period, and aquifer reserves will be reduced by more than 50%. The evaluation of management scenarios showed that their implementation not only will protect aquifer reserves but, in addition to meeting 100% of the water needs, will result in sustainable exploitation of groundwater resources. [ABSTRACT FROM AUTHOR]

Golestan Dam Lake is located 12 kilometers east of Gonbad City and was constructed in 1379. The volume of the Golestan Dam reservoir is 52 million cubic meters and its area is 1500 hectares, which was built for the purposes of agricultural and aquaculture operations.. The present study on phytoplankton biodiversity and its relationship with the primary productivity of the Golestan Dam reservoir was conducted from April to July 2019. Furthermore, water quality parameters such as transparency, pH, alkalinity, free carbon dioxide, air and water temperature, dissolved oxygen, primary productivity, conductivity, nitrate-nitrogen, and orthophosphate were analyzed along with qualitative and quantitative estimation of phytoplankton. The results indicated that the average primary productivity or gross primary production (GPP) was 0.399 ± 0.081 gcm3h-1, Net Primary Production (NPP) (0.307±0.061 gcm3h-1) and Community Respiration (CR) 0.094±0.024 gcm3h-1 in the surface. Algae in freshwater have numerous environmental functions and are based upon the recycling of nutrients. Totally 73 species of phytoplankton belonging to different taxonomic group were identified which belonges to 32 genera. Among these 32 genera,12 belongs to Cyanophyceae,8 belongs to Chlorophyceae, 10 belongs to Bacillariophyceae and 2 genera belonges to Euglenophyta. On the basis of mean primary productivity, the fish production potential of reservoir Golestan Dam showed considerable scope for the enhancement of current average production. [ABSTRACT FROM AUTHOR]

Floodplains are really important for the environment as they provide various functions for waterways, including ecological, hydrological, and geomorphic ones. During overbank flows, there are complex hydrodynamic conditions that occur as water interacts with the rough floodplain vegetation and drag forces due to the vegetation that changes the flow pattern. However, we still don't fully understand how floodplain vegetation influences channel-altering hydrodynamic forces and sediment transport. To address this, we conducted flume experiments and measured flow pattern and sediment transport under varied floodplain geometry and rigid and flexible conditions. For this purpose, a physical model was constructed in the laboratory, in which plastic rods with a diameter of 10 mm will be used as trees, and artificial grass will be grass vegetation. Thus, 36 experiments were conducted in which the sedimentation and hydraulic parameters of the flow were calculated by measuring the flow velocity, water surface, and sediment transport rate. The results show that in the floodplain with dense (rigid and flexible) vegetation, the friction coefficient (f) is even 1.5 times higher than in the floodplain without vegetation. The parameters such as flow velocity, bed shear stress and Darcy Weissbach friction coefficient increase in the vertical plane between the main channel and floodplains due to the difference in roughness between the main channel and floodplains. In addition, in the main channel, the flow resistance is almost constant and does not depend on the vegetation density. The Darcy-Weissbach friction coefficient is greatly increased in the presence of grass and tree vegetation on the floodplain, and the larger contribution of f is due to the grass vegetation. The results also showed the sediment transport rate has a direct relationship with the angle of divergence and density of vegetation and an inverse relationship with the relative depth of the flow. Therefore, as the sediment transport rate decreases in the diverging compound channel, the wavelength and height of the dunes increase. At smaller divergence angles, the dunes tend to the top of the zero line (the level of the sediments before the formation of the bed form). In the presence of vegetation, due to the increase in the roughness ratio of the floodplain to the main channel, the contribution of the main channel to the flow rate increases. As a result, the sediment transport rate increases. • The effect of rigid and flexible vegetation of floodplains on the flow pattern and transport of sediments was investigated. • The friction coefficient was 1.5 times higher than in the floodplain without vegetation in divergent compound channels. • In the main channel, the flow resistance is almost constant and does not depend on the vegetation density. • The sediment transport rate has a direct relationship with the angle of divergence and density of vegetation. [ABSTRACT FROM AUTHOR]

User churn is an important issue in online services that threatens the health and profitability of services. Most of the previous works on churn prediction convert the problem into a binary classification task where the users are labeled as churned and non-churned. More recently, some works have tried to convert the user churn prediction problem into the prediction of user return time. In this approach which is more realistic in real world online services, at each time-step the model predicts the user return time instead of predicting a churn label. However, the previous works in this category suffer from lack of generality and require high computational complexity. In this paper, we introduce ChOracle, an oracle that predicts the user churn by modeling the user return times to service by utilizing a combination of Temporal Point Processes and Recurrent Neural Networks. Moreover, we incorporate latent variables into the proposed recurrent neural network to model the latent user loyalty to the system. We also develop an efficient approximate variational inference algorithm for learning parameters of the proposed RNN by using back propagation through time. Finally, we demonstrate the superior performance of ChOracle on a wide variety of real world datasets. [ABSTRACT FROM AUTHOR]

Modularity as a system of separate and independent sub-tasks is the appropriate way to improve the performance of artificial neural network (ANN) models in hydrological processes. Using this approach, a block combined neural network (BCNN) structure incorporated with genetic algorithm (GA) and an additional decision block is suggested in this study. The optimum topology of embedded networks in each block was detected using a vector-based method subjected to different internal characteristics. This model was then applied on 879 bedload datasets, considering velocity, discharge, mean grain size, slope, and depth as model inputs over streams in Idaho, USA. The correct classification rate of predicted bedload using BCNN (89.77%) showed superior performance accuracy compared to other ANNs, and to empirical models. Results of computed error metrics and confusion matrixes also demonstrated outstanding progress in BCNN relative to other models. We show that BCNN as a new method with an appropriate accuracy level could effectively be adopted for bedload prediction purposes. [ABSTRACT FROM AUTHOR]

The aim of this research was to evaluate the antibacterial activity of the muscle wall extracts of sea cucumber, Stichopus horrens, against Lactococcus garvieae, Streptococcus iniae, Aeromonas hydrophila, and Yersinia ruckeri bacteria in rainbow trout using the disk-diffusion and well-diffusion methods. In this study, nine sea cucumbers (with the mean weight of 1690 ± 12.18 g) were randomly obtained from two locations in Chabahar Bay, Iran in November 2018. The muscle wall of the body was extracted with each of the ethyl acetate, methanol, and acetone organic solvents. The antibacterial activities of extracts were determined. Only the ethyl acetate extracts of S. horrens in the concentrations at 8 and 12 mg/mL had an inhibitory effect on all the examined bacteria. Y. ruckeri and A.hydrophila bacteria were sensitive to the acetone extracts. The best property was recorded with the S.horrens ethyl acetate extracts, with the MIC value of 0.625 mg/mL against S. iniae and L. garvieae. The MIC values ranging from 0.626 to 1.25 mg/mL were also displayed with the acetone extracts against Y. ruckeri and A. hydrophila, respectively. In conclusion, the ethyl acetate extracts of S. horrens displayed the best spectrum of bactericidal effect obtained from four bacteria strains examined. [ABSTRACT FROM AUTHOR]

The high pressure of water distribution networks (WDNs) increases leakage, bursts, and water consumption. Pressure-reducing valves (PRVs) are widely used in WDNs because of their flexibility and effectiveness in pressure management. This paper studies pressure management by locating and adjusting PRVs in WDNs, considering the proper objective function and the suitable optimization algorithm. The single-objective algorithms and the EPANET hydraulic simulator in MATLAB programming are combined to manage the pressure. Initially, the proposed method improved by selecting the optimal optimization algorithm and objective function. Both fixed outlets and time-modulated modes of PRVs for two ZJ and Bellingham WDNs as case studies were used. Considering the cost, reliability, hydraulic performance, and leakage, the results were then analyzed and compared by changing the number, location, and adjustment of each PRV. The outcomes show the effect of choosing the best algorithms and cost functions on the results. The results also show that this method increases the reliability and controls the nodal pressure to a desired level in WDNs. Practical Applications: Leakages in water distribution networks (WDNs) are problematic for utilities and other governmental agencies. Pressure management in WDNs is inevitable to reduce the rate of bursts and leaks. Using fixed- and time-modulated pressure-reducing valves (PRVs) is essential for smart pressure management in WDNs. This study presented a method for positioning and adjusting PRVs in WDNs. The proposed method was applied to ZJ and Bellingham WDNs by choosing the best optimization algorithm and objective functions. The grey wolf optimizer (GWO) algorithm is proposed as one of the best algorithms for this subject. The presented method tries to provide the best plan for pressure management by examining the cost, leakage, and reliability. The results show that the presented method effectively increases reliability and reduces leakage in WDNs. [ABSTRACT FROM AUTHOR]

Drought is a type of destructive hydro-climatic disaster that has a significant impact on agriculture and natural resources. Meteorological drought features, including severity, duration, and peak, exhibit various patterns in different climatic regions and geographical conditions. Several indices have been developed to assess the drought potential of different areas across the world, among which the drought hazard index (DHI) is one of the most commonly employed for semi-arid and the flat regions. This study investigates the effects of the elevation and precipitation on DHI, which has received little attention in previous studies. For this purpose, DHIs were computed for 15 stations located at different elevations of the study area over 31 years by considering the occurrence of various drought classes with different weights. The results showed that the elevation and mean precipitation both have inverse effects on the DHI in the study area, which means that the DHI increases when the elevation and mean precipitation are low. The results of the estimation of the DHI for three different periods (i.e., 6, 9, and 12 months) revealed that a 9-month period is optimum for DHI estimations in terms of the reliability of the results. [ABSTRACT FROM AUTHOR]

Groundwater vulnerability assessment is a general method for studying groundwater pollution. This study aimed to assess the pollution risk of groundwater with nitrate and arsenic. Risk is comprised of two parts: calculation of occurrence probability map and composition of occurrence probability map with groundwater vulnerability model. To draw up a groundwater vulnerability map, the SINTACS model was used. The correlation of the model with nitrate and arsenic concentrations was investigated. The correlation coefficients of the SINTACS model with nitrate and arsenic were r = 0.70 and r = 0.85, respectively. According to sensitivity analysis, we concluded that the SINTACS model had the least sensitivity to hydraulic conductivity. To prepare the occurrence probability map, nitrate and arsenic concentrations were combined separately with the groundwater recharge potential model. Finally, the risk map was prepared by combining the occurrence probability map and groundwater vulnerability with the SINTACS model. The results revealed that 14.72% of the study area had a high risk of nitrate and 35.33% had a high risk of arsenic. The areas with high pollution risk are those which are considered agricultural lands based on the land use map. [ABSTRACT FROM AUTHOR]

Scouring is one of the major threats to the stability of bridge abutments constructed over rivers. The present study investigated the usefulness of abutment slots in reducing the scour depth around bridge abutments with vertical walls, experimentally. Nine experiments with no slot and hundred experiments with slots were conducted in clear water conditions. Four subcritical flow conditions (Froude number less than 1) were investigated. For each flow condition, 25 different slot models having different sizes, and vertical and horizontal positions were considered. The results indicated that the slots having heights equivalent to half of the flow depth are more effective in reducing scouring if they are located closer to the bed. Increasing the slot height improves the performance. The best performance is achieved when the slot begins from the water surface and extends below the bed (equal to the scour depth in the model without the slot). Further, the results showed that the greater the distance of the slot is from the abutment nose and closer it is to the channel wall, the more effective the slot would be. Therefore, the most effective slot model is the model in which the slot height equals the distance from the water surface to below the bed, and when it is attached to the channel wall. For different slot models, in different flow conditions, the percentage of reduction of scour depth varies from 20 to 100%. [ABSTRACT FROM AUTHOR]

The management and operation of water distribution networks (WDNs) by establishing district metered areas (DMAs), especially in existing and old WDNs, has many advantages, including water leakage control, ease of operation, and network management in emergencies. Using DMAs in existing WDNs designed and developed traditionally is a challenging issue because of the need to cover several criteria. In the present study, a method for creating DMAs is suggested to minimize the cost as well as to reduce the average pressure in high-pressure WDNs. The proposed method uses the Girvan–Newman clustering and nondominated sorting genetic algorithm (NSGAII) optimization algorithms. This method was implemented on Modena's and Wolf–Cordera Ranch's WDNs. The proposed method can generate several solutions based on performance indicators, including cost, hydraulics, and quality. The results show that by applying the proposed method in the Modena and Wolf–Cordera Ranch WDNs, the average pressure of the networks was reduced by 17% and 31%, respectively, in comparison with the primary WDNs in the base demand and peak demand conditions. This method can be used by water utilities for partitioning WDNs, especially when the pressure is high. [ABSTRACT FROM AUTHOR]

This paper introduces a 'collocated discrete subdomain meshless method' to solve shallow water equations for free-surface flows with conservation of sediment mass. The computational domain in the method is discretised by distributed nodal points. Shape functions are made using the moving least-squares method for efficiency and simplicity. A number of collocation points, independent of nodal points, are used to form the specified residual function. The sum of residuals at the collocation points for each subdomain is zero in the problem domain and boundaries. In addition, boundary conditions are readily enforced. The model was verified by comparing results of simulated and physically modelled dam-break flows. There was good agreement between the analytical solution and experimental measured data, and a high convergence rate and efficiency were achieved. The method appears to have significant potential for investigating a variety of problems concerning coupled flow with sediment transport. [ABSTRACT FROM AUTHOR]

This study aimed to investigate some key aspects of the reproductive strategy of Ocypode rotundata Miers, 1882 from southwest beaches of Qeshm Island, Persian Gulf, Iran, by providing information regarding its sex ratio, sexual maturity, spawning period and fecundity. Samples were taken monthly, from February 2015 to January 2016. Size at the onset of morphometric maturity was estimated at 38.57 mm carapace width. The overall sex ratio (males/females) was observed as 1.13 : 1.00. On monthly based analyses, the sex ratio showed no significant differences, although a significant deviation was observed toward males in the larger size classes. According to the gonadosomatic index (GSI), gonad maturity and occurrence of ovigerous females, the main breeding season occurs from March to October, with a remarkable peak in June. Fecundity ranged from 24 152 to 10 5287 eggs per individual, with a mean value of 52 389 ± 25 660. The ratio between fecundity and carapace width varied from 632 to 2044 eggs/mm (mean: 1198 ± 472 eggs/mm) and fecundity relative to total mass varied from 771 to 1965 eggs/g (mean: 1336.66 ± 425.43 eggs/g). The reproductive output ranged from 1.04 to 3.78 (mean: 2.35 ± 0.90). The shape of the egg was spherical and it included 6 stages of growth, ranging from fully filled with yolk to fully occupied by the embryo. We concluded that reproduction in O. rotundata is seasonal, and that spawning occurs in an appropriate period to ensure maximum survival of the offspring. The fecundity of O. rotundata is higher than that of other species of Brachyura, with GSI variations being related to temperature. Overall, the results of this study provide relevant information for the reproduction in general and the breeding seasons of O. rotundata, whicht can be useful for conservation and management policies aimed at preserving the biodiversity of ghost crabs along the Persian Gulf’s sandy shores. [ABSTRACT FROM AUTHOR]

This experiment was conducted to illustrate the effect of dietary taurine levels on Persian sturgeon, Acipenser persicus (mean weight of ~35 g) fed plant-based diet. A basal diet containing low level of fishmeal (19%) was formulated containing 0.05% endogenous taurine (control diet). To this diet were added five levels of exogenous taurine: 0.25 (0.25T), 0.5 (0.5T), 0.8 (0.8T), 1.2 (1.2T) and 1.6% (1.6T). These diets were fed to the experimental fish for 42 days. Results showed that growth performance decreased and food conversion ratio increased as dietary taurine increased, although no significant difference was observed between the control and 0.25T treatments. Increased dietary taurine led to increased carcass moisture and decreased carcass lipid percentages. Feed intake was significantly and negatively correlated with dietary taurine. Carcass taurine content significantly increased with dietary taurine elevation up to 1.2% and then decreased. Hepatic taurine content showed a significant increase in 0.25T treatment and then decreased along with dietary taurine elevation and reached the control values at 1.6% taurine level. Dietary taurine elevation led to more hepatic damages compared to the control. In conclusion, although within the range reported for other studied fish, the tested taurine levels in this study might be supra-optimal causing adverse effects in Persian sturgeon and further study with lower taurine levels is encouraged. [ABSTRACT FROM AUTHOR]

The activity of cooperatives is one of the important activities of the fisheries sector and its knowledge performance and economic funds can be effective in deciding on investment in this sector as well as economic planning. The aim of this study was to determine the role of cooperatives in the optimal economic use of dual-purpose dams in aquaculture in Mazandaran province from 20 selected cooperatives in 2016-2017. To ensure the completeness of the questionnaire, before starting the main stages of the research, five units were randomly referenced and the questionnaire was reviewed and finalized with Cronbach's alpha coefficient. The results showed that the fishing industry of Mazandaran province is one of the productive activities and has an effective role in transforming the methods of exploiting provincial facilities. The comprehensive data analysis method presents the relative efficiency of each production point by calculating the ratio of the total weighted product to the total weighted input. According to the obtained average technical efficiency, it was found that most sealing cooperatives used inputs and facilities as efficiently as possible and according to the calculated average technical efficiency (above 83% on average), if these factors are used better, they can increase the technical efficiency of the units by 20.8%. In this regard, and based on the linear programming method provided for these units, it is possible to plan for the production and target values of each unit. [ABSTRACT FROM AUTHOR]

We tested the effect of fish oil (FO)-enrichedArtemiaon growth performance and stress resistance in tiger barb (Puntius tetrazona) larvae. Tiger barb larvae (˜2.31 mg) were fed FO-enriched (2.5, 5, 7.5%) or nonenrichedArtemianauplii for 14 days, followed by 14 days on nonenrichedArtemia. FO enrichment significantly increased n-3 HUFA and n-3/n-6 ratio of nauplii. There was no significant difference in survival rate among the treatments. Fish fed enriched nauplii grew better at days 14 and 28, and exhibited greater resistance to osmotic and hypoxia stress. There were no significant differences in growth and stress resistance among FO-enriched groups. [ABSTRACT FROM PUBLISHER]

A study was conducted to investigate the effects of dietary citric acid (CA) (0, 1%, 2% and 3%) on the calcium (Ca) and phosphorus (P) contents of muscle, scute and serum of Beluga ( Huso huso) juveniles (25.1±1.9 g). After 8 weeks of feeding on the experimental diets, the Ca and P contents of muscle, scute and serum were measured. The results revealed that the addition of 2% and 3% CA significantly increased the Ca and P contents of muscle and serum. Dietary CA had no effect on the Ca content of scute, but the P content of scute was significantly higher compared with additional 1% CA and the control. These results indicate that the addition of CA to the diet of Beluga increased the bioavailability of Ca and P, thereby increasing muscle and scute mineralization. [ABSTRACT FROM AUTHOR]

Abstract: A 2×3 factorial experiment was conducted to evaluate the effect of partial substitution of dietary fish meal with soybean meal and citric acid (CA) supplementation on growth, food utilization, muscle composition and nutrient digestibility of Beluga, Huso huso. Three isonitrogenic and isoenergetic diets, as SBM1 (soybean meal protein (SBP):fishmeal protein (FP)=1:3), SBM2 (SBP:FP=2:3) and SBM3 (SBP:FP=1:1) containing two levels of CA (0 and 30gkg−1) were fed to triplicate groups of fish for 8 weeks. The results revealed that adding CA increased (P<0.05) the weight gain (WG), specific growth rate (SGR) and protein efficiency ratio (PER) and decreased (P<0.05) food conversion rate (FCR) whereas partial substitution of fishmeal with soybean meal decreased (P<0.05) growth performance. Partial replacement of fishmeal with SBM (P=0.021) as well as CA supplementation (P=0.019) and their interaction (P<0.001) affected hepatosomatic index (HSI). No differences (P>0.05) were observed for viscerosomatic index (VSI) among treatments (P>0.05). No differences (P>0.05) were detected in moisture, protein of muscle sample among treatments, but lipid content was reduced (P<0.05) while ash content increased (P=0.035) by CA. Soybean meal decreased (P<0.05) nutrient digestibility, whereas CA improved apparent protein and phosphorus (P) digestibility (P=0.011 and P<0.001 respectively). No interaction (P<0.05) between levels of SBM and CA was found on these parameters. Results of the present study indicate that Beluga has a limited ability to utilize SBM as a protein source in practical diets whereas CA can improve growth and nutrient utilization in Beluga. [Copyright &y& Elsevier]

This paper reports an improved version of the numerical method used in a previous study on the dynamic simulation of purse seine gear in three dimensions. The improvement is achieved by refining the mass-spring model to take into account both the drag coefficient as a function of the attack angle and Reynolds number as applied to the setting operation of the purse seine gear. The validity of the numerical simulation is assessed by comparing the measured and calculated values for the sinking depth of the net. The numerical simulation is used to examine the sinking performance of the different designs in which large meshed-panels and netting materials are used together in the main body section of the netting. The results indicate that, compared to the prototype net, nets bearing larger mesh panels require more sinking depth with much more pronounced operational depth at corresponding times of the fishing operation when heavier netting material is used. Moreover, in the new net designs, lower tensile forces are exerted on both ends of the pure wire during pursing. The new net constructions with regard to the operational depth represent alternatives that may reduce the potential problem of frequent failed setting of the tuna purse seine gear. [ABSTRACT FROM AUTHOR]

A 44-day rearing trial was conducted to examine the enrichment of Artemia urmiana nauplii with vitamin E and highly unsaturated fatty acid (HUFA) and its effects on the growth performance, survival and stress resistance of great sturgeon, Huso huso, larvae. Cod liver oil (EPA 18% and DHA 12%) and α-tocopherol acetate were used as lipid and vitamin E sources. Beluga larvae at the first exogenous feeding with 69±5.9 mg body weight were randomly distributed into four treatments and three tanks were assigned to each diet. The test treatments were as follows: larvae fed with HUFA+20% and HUFA+50% (w/w) vitamin E-enriched Artemia nauplii (E1 and E2 groups, respectively), HUFA without vitamin E (HUFA group) and non-enriched Artemia (control group). All treatments fed non-enriched Artemia for the initial 5 days after first feeding and then fed enriched Artemia for 7 days. After the period of enrichment, larvae were fed with daphnia from the 13th to the 40th day. At day 40, submersion in salt water (6 ppt for 4 days and 12 ppt for 2 days) and warm water (33 °C for 2 days) was performed to evaluate larvae resistance to salinity and temperature stress. Final weight, daily growth rate, specific growth rate and weight gain were higher in beluga fed with enriched Artemia. The highest growth rates were observed in E1, whereas survival was not significantly different between groups. Use of vitamin E and HUFA significantly increased fish resistance to a salinity of 12 ppt and the lowest stress resistance was observed in the control group. Stress tolerance was not significantly different at 6 ppt and 33 °C between groups. There was no comparable difference in the haematocrit index under stress conditions. These results indicated that the enrichment of Artemia with essential fatty acids and vitamin E can affect some growth and stress tolerance factors in great sturgeon, Huso huso, larvae. [ABSTRACT FROM AUTHOR]

• The epistemic uncertainty is considered for time-dependent fuzzy reliability analysis of corroded RC beam. • Fuzzy time-dependent reliability index is obtained using α -cut approach. • The optimization method of hybrid HGAPSO is proposed to search the bounds of reliability index. • Three-term conjugate method is used for computing the reliability index of RC beams under corrosion. Evaluation of reinforced concrete (RC) structures which are subjected to the damaging environmental factors during the service life is critical. The service life model, the effects of environmental factors with their extent of damage during the service period of the structure could be predicted. Various uncertainties that came with this assessment confidence in the results should be taken by a safe margin. Structural reliability methods are one of the best tools to calculate the life model that considers the random properties of parameters. However, if the epistemic and inherent uncertainty of parameters with their time-dependent changes considered, the life model is more reliable. The reinforcement corrosion is the most damaging mechanism that causes the premature degradation of RC structures and substantial economic losses each year. In this work, the time-dependent reliability of an RC beam with chloride-induced corrosion considering epistemic uncertainty via an efficient numerical procedure is developed. Fuzzy time-dependent reliability index has been calculated using α -cut approach based on a hybrid version of genetic algorithm (GA) and particle swarm optimization (PSO), namely HGAPSO applying three-term conjugate reliability method. Results showed that the proposed numerical approach could efficiently and robustly estimate the fuzzy time-dependent reliability index. [ABSTRACT FROM AUTHOR]

Flooding in urban area affects the lives of people and could cause huge damages. In this study, a model is proposed for urban flood management with the aim of reducing the total costs. For this purpose, a hybrid model has been developed using SWMM and a quasi-two-dimensional model based on the cellular automata capable of considering surface flow infiltration. Based on the hybrid model outputs, stormwater management measure scenarios are proposed. In the next step, a damage estimation model has been developed using depth-damage curves. The amount of damage has been estimated for the scenarios in different rainfall return periods to obtain the damage and cost- probability functions. The conditional values at risk are estimated based on these functions which are the basis of decision making about the stormwater management scenarios. The proposed model is examined in an urban catchment located in Tehran, Iran. In this study, five scenarios have been proposed on the basis of different stormwater management measures. It has been found that the scenario of using permeable pavements results in the lowest risk. The proposed model enables the decision makers to choose the best scenario for the stormwater management with the minimum cost taking into account the risk associated with each scenario. [ABSTRACT FROM AUTHOR]

The estimation of river run-off is a complex process, but it is of vital importance to the proper operation of reservoirs, the design of hydraulic structures, flood control, drought management and the supply of water and electricity. The high uncertainty in rainfall–run-off modelling and lack of data has made the development of rainfall–run-off models with acceptable levels of accuracy and precision challenging. Furthermore, the rainfall–run-off models commonly do not provide an explicit relationship between run-off and other variables to be used for run-off-related investigations. To overcome the knowledge and information shortage in rainfall–run-off modelling, data-driven models have been used instead of conceptual models for the development of rainfall–run-off models. In this paper, three data-driven models, the genetic algorithm-support vector regression (GA-SVR), genetic algorithm-artificial neural network (GA-ANN) and the group method of data handling (GMDH) have been used to predict the monthly run-off of the Gavehroud basin. Their performances are compared with a conceptual hydrological model (HYMOD) whose parameters are calibrated using the GA. To this end, the monthly data on precipitation, temperature and run-off at the Gavehroud basin over 49 yr (1960–2009) were analysed. Evaluation of the results using performance evaluation indicators showed that the hybrid model of GA-SVR provided better accuracy in predicting the nonlinear behaviour of flow data than the GA-ANN, GMDH and HYMOD. [ABSTRACT FROM AUTHOR]

Satellite precipitation products are important data sources in different spatial resolutions, time scales, and spatio-temporal coverage. In this study, the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) satellite precipitation product with a high spatial resolution (0.05°) is evaluated in the period of 1987 to 2017 over different climate regions of Iran. The accuracy of the satellite product is compared with the 68 ground-based meteorological stations over different time scales (i.e., daily, monthly, and annual) and precipitation classes. Results show that the performance of CHIRPS depends on the time scale, precipitation depth, and climate type. The best performance of the product (CC = 0.80, FRMSE = 0.57, NSE = 0.63) across the country is observed in the annual time scale, while the monthly product offers the best performance in the regional scale. The product provides inadequate performance (CC = 0.34, FRMSE = 5.72, NSE = − 0.2) in daily time scale across the country and most of the climatic regions. The product is found to be most accurate in the south and southwest of the country, while the lowest performance is observed over the Caspian coast. The CHIRPS satellite provides the best performance in detection of no/tiny precipitation (POD > 0.90) and the worst performance in light and low, moderate precipitation (POD < 0.10). It is expected that the findings of the current study can be used to manage the water resources and mitigate the disaster at the national level. [ABSTRACT FROM AUTHOR]

In structural engineering, damage detection in concrete gravity dams (CGDS) is a practical problem. Dam destruction can have severe financial consequences and may even lead to fatalities. Therefore, structural health monitoring in advance is crucial. In this regard, a well-known CGD, namely the Pine Flat Dam, has been chosen for the Finite Element Modeling. In this paper, damage is induced in the dam neck through elasticity modulus reduction by 40 % and 80 %. In addition, after applying Northridge earthquake, the acceleration in structure nodes for intact and damaged cases are recorded in vector formats. Using various methods, such as Discrete-time Fourier Transform (DTFT), Wavelet transform and Wiener transform, the differences between these two signals are investigated. The standard deviation (S.D.) of variations is chosen as the performance metric and is applied to the signal amplitude between intact and damage observations/signals. The reason why several signal processing algorithms are used is finding an approach which shows more clearly the differences caused by the destruction. This is evaluated via S.D. values for different algorithms. The results confirm the superiority of DTFT over other given algorithms. DTFT has a negligible outperformance (approximately zero dB) with respect to the Wavelet transform in both the crest and the lower nodes of the dam. This rate for DTFT and Wavelet is 10dB higher than that of Wiener and 35 dB in comparison with the simple amplitude difference. Moreover, the detection thresholds for the given methods are compared, and it is verified that the DTFT and Wavelet indicate the best performance. [ABSTRACT FROM AUTHOR]

Reservoirs are crucial for water storage, flood control, and electricity generation. At the same time, evaporation in dam reservoirs causes water losses. This study evaluates the effect of weather conditions on the prediction of evaporation from the dam reservoir, and there are several developed models to predict evaporation under different scenarios. Using the deep neural network model long short term memory (LSTM) with a series of modern meta-heuristic algorithms, the present research aims to achieve an acceptable accuracy on weather parameters. The present study investigates the ability of the LSTM deep neural network and meta-heuristic algorithms of Artificial Bee Colony (ABC), Horse Herd Optimization (HOA), and Marine Predators (MPA) to develop an evaporation rate forecasting model for a tropical area in the Dez Dam reservoir, Khuzestan province, Iran. To investigate the effect of different input variable patterns on the prediction accuracy of the case model, twenty-eight scenarios were investigated for the input architecture along with the LSTM model and its combination with meta-heuristic algorithms. The models include ABC-LSTM, LSTM-HOA, and LSTM-MPA, respectively. The results showed that the combined LSTM-MPA model with RMSE, MAE, KGE, and WI evaluation criteria equal to 81.926 mm/month, 53.684 mm/month, 0.850, and 0.816, respectively, performs better than other meta-heuristic models. The examined deep meta-heuristic models are suggested for predicting evaporation from the Dez dam reservoir with limited information because the results show that they have more appropriate prediction capability than the LSTM Model. [ABSTRACT FROM AUTHOR]

Marine aquaculture has been developing over the past two decades given the demand for seafood products and the decline of wild fisheries resources. Aquaculture and environmental interactions have also been given an especial attention to investigate the impacts, to improve fish culture strategies and to prevent pollution. In this study, a predictive model with different scenarios was utilized to assess the impacts of shrimp farm effluent through nitrogen dynamic in the Gomishan Wetland, southeast of the Caspian Sea. The results showed that after 2014, total nitrogen content exceeded its standard limits. The worst scenario with the maximum capacity of the farms and the minimum water volume, represented maximum nitrogen concentration of 0.8 mg/L on the 9th day of rearing. The most ideal scenario achieved the maximum amount of shrimp production (238 tons) with no negative influences on wetland water quality, if the water depth in Gomishan Wetland remains equal to 30 cm. These models can aid managers for a better understanding about the aquaculture systems and to reach more sustainable production with the minimum risk of coastal and marine pollution. • A predictive model evaluated the sustainability of shrimp aquaculture. • The model assessed impacts of effluent through nitrogen dynamic. • The scenarios showed total nitrogen content exceeded its standard limits. • These models can aid to reduce the risks and to improve the farming system. [ABSTRACT FROM AUTHOR]

In this study, performance of an in-stream hydro-kinetic turbine and its impacts on a simplified river channel (known as a compound open-channel) flow has been numerically examined. To this end, a steady Reynolds-Averaged Navier-Stokes solver has been employed together with the moving reference method to simulate the turbine rotation as well as the Reynolds Stress Model (RSM) as the turbulence closure. The results showed that the presence of a hydro-kinetic turbine causes dramatic changes in the natural flow structure of the compound channel, which varies depending on the location of turbine installation. Comparison of turbine installation in various locations in the cross-section of the channel showed that minimum effects on the natural flow conditions have been occurred in the installation at the main-channel being far from the bed. It has also been observed that the bed shear stress remains virtually constant for different hydro-kinetic turbine locations. Values of the power coefficient indicate that the highest value of maximum power coefficient is obtained where the hydro-kinetic turbine is installed at the interaction zone of the compound open-channel. This observation implies that cellular secondary currents of the compound channel have positive effects on the turbine power. Finally, it is noted that the thrust coefficient variation with the installation location is insignificant compared to the variation of this coefficient with respect to the inlet velocity and the ratio of the blade flow speed to the flow speed. • Performance and impacts of an in-stream hydro-kinetic turbine on a compound open-channel flow have explored. • Turbine makes changes on the flow structure of compound channel which varies respect to the location of installation. • Minimal effects on the natural flow condition have been observed in the main channel far from the bed installation. • Maximum turbine power has been obtained as turbine installed in the interaction zone of compound open-channel. [ABSTRACT FROM AUTHOR]

Nowadays, human societies encounter the challenges to provide food and livelihood of the people. The aquaculture industry is one of the essential solutions dealing with these problems. Site selection is a beneficial way to reduce pressure on the ecosystem and to understand the environment's potential. In this study, suitable sites for sturgeon cultivation in the southern coast of the Caspian Sea, Golestan Province, Iran were optimized using multi-criteria evaluation (MCE) method. First, the criteria into three groups were categorized: environmental, infrastructural, and water resources. Then, the maps were Fuzzy based on the sturgeon's characteristics and expert opinions. Afterward, to determine the effect of each criterion, criteria were weighted by the Analytic Hierarchy Process (AHP). Finally, based on the weighted linear combination (WLC) approach, the layers and created the final map were combined. Results represented three sites which were most desirable for sturgeon farming in the Golestan Province coastal area and there are 24,638 ha in this region which has the highest desirability for sturgeon farming. Factors such as distance to water resource and distance to roads, industrial and residential areas have had the highest effect on the process of site selection for sturgeon farming. Using MCE method, site selection makes a reasonable decision with little data and creates an understanding of the conflicts among other users in the coastal lands. • The huge decrease in sturgeon catches in the Caspian Sea has led to an increase in attention to the culturing of sturgeons. • A case study at Golestan Province, Iran was applied to selecting the desirable sites for sturgeon farming. • Multi-criteria evaluation (MCE) method was used to select suitable sites for aquaculture. • Results represent three sites which are most desirable for sturgeon farming in the Caspian Sea coastal area. [ABSTRACT FROM AUTHOR]

Seaweeds contains different types of polysaccharides with high abilities. The aim of this study was to determine the potential of fucoidan polysaccharides for wound-healing properties. Fucoidans of two species of Padina (P. tetrastromatica and P. boergesenii), collected from the Persian Gulf northern coastal area, were extracted and analyzed using high-performance anion-exchange chromatography. Purified fucoidans were used to prepare a 2% topical ointment. Under aseptic conditions, two identical paravertebral full-thickness skin wounds (either by burn or excision) were made in 40 anesthetized male rats allocated into 4 groups. Either fucoidan ointments or the vehicle (ointment base) were applied to rats' wounds twice daily for 14 days. In addition to the examination of wound area reduction (days 3, 7, 10, and 14) and histopathological assays (days 7 and 10), tissue specimens were taken to the laboratory. Fucoidans obtained from both seaweeds induced significant wound area reduction compared to the vehicle at some time points after treatment. Histopathological examinations showed improvement in some healing signs including angiogenesis, collagen fiber formation, and epidermis formation. In conclusion, both species of Padina have significant wound-healing effects and fucoidan polysaccharides are the active constituents for this healing property. However, fucoidan obtained from P. boergesenii showed superior effects in this regard. [ABSTRACT FROM AUTHOR]