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Fishmeal is an important protein source for largemouth bass (Micropterus salmoides). However, the production of fishmeal is decreasing each year and the price of fishmeal is rising. Therefore, it is necessary to find new high-quality and suitable protein sources. This study used a mixed animal protein source (chicken meal:blood meal:shrimp meal:brewer's yeast = 50:12.5:25:12.5) to replace fishmeal. Using a 48 % fishmeal group as the control, five diets with different fishmeal levels (FM48, FM44, FM40, FM36, FM32) were established to determine the effects on largemouth bass growth performance, liver health and intestinal health. There were no significant differences in the percentage weight gain, specific growth rate, feed conversion rate, and condition factor of largemouth bass, but the hepatosomatic and viscerosomatic indexes were significantly decreased when the dietary fishmeal level was reduced to 40 %. The content of taurine, glycine, and histidine was significantly reduced in the muscle of largemouth bass fed the FM32 diet compared with those fed the FM48 and FM44 diets. Mixed protein feed reduced the total bile acid content and increased the low-density lipoprotein cholesterol content in the plasma of largemouth bass. The replacement of fishmeal with the mixed protein source inhibited the expression of tnf-α and caspase 3 and enhanced the expression of apoa1 in the liver, as well as enhancing the protein expression of FXR and SREBP and inhibiting the protein expression of P-PPARA in the liver. The intestinal pparα expression was suppressed when dietary fishmeal was replaced. When dietary fishmeal decreased, the mucosal folds height and muscle layer thickness also decreased. In conclusion, partial replacement of fishmeal with the mixed protein source did not affect the growth performance, while lipid metabolism and intestinal health were negatively affected when dietary fishmeal levels were below 36 %. [Display omitted] • Dietary replacement of fishmeal had no significant impacts on the growth performance of largemouth bass. • Dietary replacement of fishmeal would affect the cholesterol and bile acid metabolism of largemouth bass. • Excessive replacement of fishmeal (FM36 and FM32) could cause oxidative stress and intestinal damage in largemouth bass. [ABSTRACT FROM AUTHOR]

• Joint dispatching of autonomous mobility-on-demand system and power system. • Multi-spatiotemporal scale dispatching models in power-traffic coordination. • Dispatching performance validated on a large-scale real-world case. • 15% reduction of total carbon emissions with vehicle-to-grid (V2G) considered. • Sensitivity analysis on fleet size, renewable energy profile, power system capacity. Electrified autonomous mobility-on-demand (E-AMoD) systems will play a crucial role in future cities, which couple the carbon emissions generated by the transportation system and the power system. This paper proposes a joint dispatching framework to facilitate city decarbonization by coordinating the fleet operator and power system operator. Given the substantial differences in spatial and temporal dispatching scales between the two systems, this framework effectively integrates micro vehicle-level service dispatching with macro fleet-level charging scheduling. Firstly, a novel bipartite matching model efficiently solves the short-term passenger serving and rebalancing dispatching at the vehicle level. The service dispatching results are then aggregated as spatial-temporal transition flows across different areas and time intervals. Incorporating these mobility constraints, the long-term charging-discharging scheduling at the fleet level is captured as an expanded network flow model and integrated with the power system dispatching model, which aims at renewable energy utilization and carbon emission mitigation. Finally, the fleet-level scheduling results are disaggregated to the serving-rebalancing-charging sequences of each vehicle, for practical implementation. To validate the proposed framework, numerical experiments are conducted on a large-scale real-world case. Multiple charging schedule scenarios, including heuristic charging, smart charging, and smart charging-discharging, are investigated under both centralized and distributed supplied power systems. (1) The framework proves to be an effective solution for addressing the differences in dispatching spatiotemporal scales, calculation efficiencies, and privacy concerns between power and traffic systems. (2) Through power-traffic coordination, the E-AMoD fleet demonstrates its ability to alleviate 8% of average renewable energy curtailment and reduce nearly 15% of the total emissions in a power system installed with renewable distributed generators. (3) Furthermore, the extent of emission mitigation effects is influenced by critical factors such as fleet size, renewable energy profile, and power system capacity. Overall, the E-AMoD system show great potential as mobile storage devices to provide spatial-temporal flexibility to the power system and contribute to city decarbonization. [ABSTRACT FROM AUTHOR]

Abstract An 8-week feeding trial was conducted to evaluate the effect of fish-meal replacement on growth performance, protein synthesis and immune response of juvenile Pacific white shrimp, Litopenaeus vannamei reared at low salinity (7‰). Five isonitrogenous and isolipidic diets were formulated to contain graded levels (25, 20, 15, 10 and 5%) of fish-meal. High quality alternative solutions were performed, crystalline amino acids, phytase, mannan oligosaccharides and some micro-nutrients were supplemented in the low fish-meal diets. Each diet was randomly assigned to triplicate tanks, each tank with 30 shrimp (mean weight 0.3 g), the shrimp were fed 3 times a day. Weight gain and survival were decreased with the decreasing dietary fish meal levels. When dietary fish-meal decreased, the gene expression of TOR, Raptor and eIF4E2 in hepatopancreas were decreased with the decreasing fish meal levels, eIF4E2 in intestine was decreased while 4E-BP was increased with the decreasing fish meal levels. The mRNA level of SOD in hepatopancreas decreased, and the expression of GPx and CAT increased with the decreasing FM levels. The Toll pathway was affected by dietary FM levels, the expression of Toll2, TNFSF, MyD88, Rho and p38 in intestine were increased with the decreasing FM levels. The results indicated that at low salinity condition, fish meal level lower than 15% would inhibit the protein synthesis and harm to the health of shrimp. Graphical abstract Unlabelled Image Highlights • Reduced the fish meal content in the diet would significantly affected the survival of white shrimp reared at low salinity. • The protein synthesis of white shrimp might be affected by the dietary fish meal levels. • Immune response, especially for Toll pathway, might be affected by dietary fish meal levels. [ABSTRACT FROM AUTHOR]

Abstract Subsurface arsenic (As) removal has been proposed for in situ immobilizing As in aquifers at a low cost and without post-disposal of As-containing wastes. However, the results reported for field tests are very limited, particularly when high As, phosphate (P) and iron (Fe) coexist in the groundwater. Herein the performance of single- and multiple-well operations was evaluated for in situ removing groundwater As in Jianghan Plain, central China. To enhance groundwater oxygenation, in-well electrolysis was employed in both operation modes. The groundwater in confined aquifer in Jianghan Plain contains elevated concentrations of As (272–606 μg/L), Fe2+ (4.7–14.3 mg/L) and P (0.90–1.58 mg/L). In the single-well operation with cycles of injection and abstraction, groundwater Fe2+ was completely removed but As cannot be reduced to below the World Health Organization guideline (10 μg/L) due to the high concentration and the competition of coexisting P. In-well electrolysis is cost-effective for boosting dissolved oxygen (DO) and Fe2+ removal in single-well operations. In the multiple-well operation with one abstraction well surrounded by 6 in-well electrolysis wells, removals of groundwater As, Fe, P and Mn were not sufficient because of clogging of treatment wells and incomplete capture of groundwater flowing to the abstraction well. In comparison, single-well operation is more simple and efficient for in situ treatment of groundwater As and Fe than multiple-well operation. This study provides a field example of in situ removing high As in groundwater by both single- and multiple-well operations, and underscores the difficulty in treating the groundwater with coexistence of elevated As and P. Graphical abstract Unlabelled Image Highlights • Both single- and multiple-well operations were performed in the Jianghan Plain. • In-well electrolysis was applied in multiple-well operation for oxygenation. • Single-well operation enabled the aquifer to remove Fe effectively. • Multiple-well operation removed groundwater As by about 58% before clogging. • Clogging occurred likely on the well screen rather than in the surrounding aquifer. [ABSTRACT FROM AUTHOR]

This paper presents a novel multi-objective model of active distribution network planning based on stochastic programming and uncertain random network (URN) theory. The planning model is proposed to find the final scheme with optimal alternative, location, size and operational strategy for the candidate distribution lines, transformer substations (TSs), distribution generations (DGs), static var compensators (SVCs) and on-load tap changers (OLTCs). Firstly, a scenario-based approach is developed to analyse the uncertainties in network system, such as the demand and intermittency of renewable sources. Since the impact of multiple uncertain factors on network cannot be ignored, a network frame is then modelled by uncertain and random weights of spanning tree (ST) instead of fixed value. In order to achieve the minimization of total cost, and further the selection of a minimum spanning tree (MST) with the uncertain and random weight, a 3-dimensional uncertain space is constructed based on the combination of the previous two targets. In addition, a second-order cone programming (SOCP) is applied to cope with the multi-objective, mixed-integer nonlinear nature of the proposed planning model. Simulation is performed on a modified Pacific Gas and Electric Company (PG&E) 69-bus distribution system, and the results demonstrate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

For latent heat thermal energy storage applications with phase change material (PCM) in restricted space, the factors such as container shape and heating surface must be considered. In this paper, a 2D square cavity PCM is taken as the research object, and the melting process of PCM with different square cavity aspect ratio (AR) was simulated under the condition of constant heat flux (60 W) at the left wall/bottom wall. An innovative and effective indicator, i.e., differential liquid fraction curve along with solid-liquid interface evolution is proposed to reveal the melting rate and typical phase change characteristics. The results show that the complete melting time increases with the increase of AR for both left wall and bottom wall heating conditions. For general applications, the bottom wall heating has a higher melting rate compared with left wall, especially for the cavity with AR >1. During the phase change process, the melting rate can reach its maximum value at the peak of differential liquid fraction curve with an observation of the longest solid-liquid interface. In addition, the melting pattern of high AR cavity during the latter part of the left wall heating process would become similar to the low AR case under the "scouring effect" of natural convection on the solid-liquid interface. For bottom wall cases, the natural convection waveform presents Rayleigh-Benard convection cells, and with the increase of AR, the irregularity of the vortex structure becomes more obvious. The results can provide useful guidance for accurately evaluating phase change characteristics and designing thermal energy storage system. • A typical 2D square cavity PCM is taken as the research object. • Effect of aspect ratio and heating surface on PCM melting behavior is investigated. • Differential liquid fraction is proposed to reveal the phase change characteristics. • The solid-liquid interface length is an effective indicator for thermal performance. [ABSTRACT FROM AUTHOR]

A 10-week experiment was conducted to evaluate the effects of dietary lysine levels on growth performance, lipid metabolism, anti-oxidant capacity, mitochondrial biogenesis and immune response of grass carp, Ctenopharyngodon idella. Fish (mean initial weight 51.01 ± 0.17 g) were fed seven diets containing graded levels of lysine (1.69 %, 1.79 %, 1.91 %, 2.01 %, 2.11 %, 2.24 % and 2.31 %). Results showed that fish fed the control diet (1.69 %) showed lower weight gain (WG) and higher feed conversion rate FCR than those fed 2.01–2.31 % lysine (P < 0.05). Viscerosomatic index decreased when dietary lysine increasing from 1.69 % to 2.11 % (P < 0.05). Suitable dietary lysine levels enhanced the lipolysis and mitochondrial biogenesis of grass carp. Total antioxidant capacity (T-AOC) in the liver was higher in fish fed 2.24 % dietary lysine than those fed diets containing 1.69 % and 1.79 % lysine (P < 0.05). The malonaldehyde (MDA) contents in liver decreased when dietary lysine increased from 1.69 % to 2.01 % (P < 0.05). Relative mRNA levels of glutathione peroxidase and catalase in liver and intestine were affected by dietary lysine levels (P < 0.05). B-cell lymphoma 2 (Bcl-2) mRNA level in liver was up-regulated and inhibitor kappa B kinase β (IKKβ) mRNA level in the intestine was down-regulated by increasing dietary lysine levels (P < 0.05). Second-order regression based on WG indicated the suitable level of lysine in feed of grass carp was 2.24 % (6.19 % protein). • Dietary deficiency of lysine would impair the growth performance and feed utilization of grass carp. • The protein synthesis, lipolysis and mitochondrial biogenesis of grass carp might be enhanced by lysine. • Immune response and anti-oxidant defense system of grass carp might be affected by dietary fish lysine levels. [ABSTRACT FROM AUTHOR]

Water electrolysis has been employed for in situ supplying H 2 to Pd-catalytic treatment of groundwater, but the treatment efficiency is greatly inhibited by the concomitant production of O 2 . In this study, a new dual-anode system is proposed to improve the efficiency. An inert anode and an iron anode are used simultaneously to produce O 2 and Fe(II), respectively. The quick oxidative precipitation of Fe(II) by O 2 removes both Fe(II) and O 2 , improving the utilization of cathodic H 2 for the subsequent Pd-catalytic hydrodechlorination. Feasibility tests in the lab show that Pd-catalytic hydrodechlorination of trichloroethylene (TCE) was considerably increased by the addition of an iron anode to the conventional two-electrode system. Scale-up tests at an abandoned chemical site demonstrated that chlorobenzenes in the groundwater were largely hydrodechlorinated to benzene, showing a maximum efficiency with the currents of 0.24 and 0.16 A applied to the inert and iron anodes, respectively, at the flow rate of 6 L/h. In a 3-month intermittent field test, Pd normalized rate constants of hydrodechlorinating three chlorobenzenes are comparable to the conventional means of H 2 supply, while the cost for hydrodechlorination normalized by one mole [H] is much lower. The dual-anode system is an effective means to supplying H 2 in situ for Pd-catalytic treatment. [ABSTRACT FROM AUTHOR]

• •OH induced contaminant oxidation by iron EC in bicarbonate electrolyte. • High yield of •OH occurred at pH 8.5 in bicarbonate electrolyte. • Formation of adsorbed Fe(II)-carbonate complexes favored high •OH yields. • A new kinetic model can describe •OH production and contaminant oxidation. • Results highlighted the •OH-based advanced oxidation process in iron EC. Iron electrocoagulation is designed for sustainable high-efficiency and high-flexibility water purification applications. Recent advances reported that hydroxyl radicals (•OH)-based oxidative transformation of organic contaminants can occur in iron electrocoagulation. However, there is still a lack of mechanistic understanding the production of •OH in bicarbonate electrolyte, which presents a critical knowledge gap in the optimization of iron electrocoagulation technology towards practical application. Combined with contaminant degradation, radical quenching experiments, and spectroscopic techniques, we found that •OH was produced at rate of 16.1 μM∙ h −1 during 30-mA iron electrocoagulation in bicarbonate electrolyte through activation of O 2 by Fe(II) under pH-neutral conditions. High yield of •OH occurred at pH 8.5, likely due to high adsorbed Fe(II) that can activate O 2 to enhance •OH production. Mössbauer and X-ray photoelectron spectroscopy measurements substantiated that Fe(II)-adsorbed lepidocrocite was the dominant solid Fe(II) species at pH 8.5. A process-based kinetic modeling was developed to describe the dynamic of •OH production, Fe(II) oxidation, and contaminant degradation processes in iron electrocoagulation. Findings of this study extend the functionality of electrocoagulation from phase separation to •OH-based advanced oxidation process, which provides a new perspective for the development of electrocoagulation-based next generation sustainable water purification technology. [Display omitted] [ABSTRACT FROM AUTHOR]

Dietary fish meal (FM) and fish oil (FO) replacement are crucial for the sustainable development of aquaculture. An eight weeks feeding trial was conducted to evaluate the potential replacing FM with soy protein concentrate, and the suitable FO level for a low FM diet of Penaeus monodon. A diet containing 25% FM was used as the control (C diet), and three other diets were formulated to contain 15% FM, and supplemented with 3%, 2%, 1% FO [high FO (HF), medium FO (MF) and low FO (LF), respectively]. The experiment was conducted in quadruplicates (30 shrimp per replicate, average weight 1.00 ± 0.01 g). The results indicated that besides the final body weight, there were no differences in weight gain, feed efficiency and survival rate observed among the four groups. The results of the acute salinity stress showed that shrimp fed the C and MF diets showed a similar survival rate, which was significantly higher than those fed a LF diet. Shrimp that were fed HF, MF and LF diets showed a lower level of fatty acid transport-related mRNA expression in the hepatopancreas, compared with those fed the C diet. Shrimp fed HF, MF and LF diets showed lower expression levels of superoxide dismutase, endoplasmic reticulum protein 57 and immune deficiency (IMD) in the hepatopancreas than those fed the C diet. Shrimp that were fed a LF diet showed the lowest expression levels of inhibitor of apoptosis proteins, Toll and tumor necrosis factor receptor associated factor 6 (TRAF6) in the hepatopancreas, as well as the highest expression levels of Toll, extracellular signal-regulated kinase, Relish and TRAF6 in the intestine among four groups. Intestinal microstructure damage was observed in shrimp that were fed a LF diet, and intestinal endoplasmic reticulum (ER) swelling was observed in shrimp fed MF and LF diets. In conclusion, these results indicated that the growth performance of shrimp was not affected when the FM and FO contents decreased, whereas a low content of FM negatively influenced the immune response in shrimp by modulating IMD and ER stress related gene expression. Under low FM conditions, a suitable dietary FO level would benefit to the lipid transport, hepatopancreas and intestine health, as well as the immune response of shrimp. • Reduce the dietary FM level from 25% to 15% had no negative effect on growth performance of P. monodon. • Low dietary fish oil reduced the acute salinity stress resistance of P. monodon fed low FM diet. • Low dietary fish oil impaired the immune response of shrimp through the IMD and Toll signaling pathways. [ABSTRACT FROM AUTHOR]

As an effective means to improve the efficient use of energy, multi-energy coupled systems have indicated the important direction for the development of Energy Internet in the foreseeable future. However, the uncertainties that exist in various energy networks present severe challenges to the implementation of this innovative system. In this regard, this paper proposed a multi-stage robust optimization model for the coordinated operation of an electricity-gas-transportation coupled system, which simultaneously considered the uncertainties of traffic demands, wind power, and gas fuel consumption by gas-fired units. To conform to the non-anticipative sequential decision-making process for power system scheduling, the multi-stage robust unit commitment (UC) problem was established and considered as the master problem, which was solved by introducing a linear affine rule and the robust counterpart method. The gas network operation feasibility checks in each period were then addressed as the subproblems, and the generalized benders decomposition-based decoupling-coordination strategy was developed to solve the above master-subproblems iteratively. Simulation results demonstrate that the proposed multi-stage robust UC model can achieve a scheduling solution with superior economic performance and reduced conservativeness compared to the two-stage robust UC model. Furthermore, the effectiveness of the decoupling-coordination solving strategy was verified for the multi-energy coupled system. • A multi-stage robust optimization model for a multi-energy coupled system is proposed. • The uncertainties of wind power, gas demand, and traffic demand are considered. • Robust counterpart and a linear affine rule are introduced to solve the proposed model. • A decoupling-coordination strategy is used to achieve a synergetic optimization. [ABSTRACT FROM AUTHOR]

There is an enlightening phenomenon in nature where mussels can purify water following swallowing microorganisms, debris, gravel, etc. Inspired by this phenomenon, we simulated the shell-pearl structure of a clam, and developed a unique method to synthesize Bi 2 O 3 intercalated bismuth titanate and molecularly imprinted TiO 2 microbead composites. Salicylic acid (SA) as an organic molecule (also target pollutant) plays a key role in the protection and formation of Bi 2 O 3 , which is key to obtaining the structure of mussel shell. The open shell-pearl bionic structure enables efficient transport of excited electrons across a variety of surface interfaces, while suppressing the complexity of photogenerated carrier that drives photocatalytic efficiency. Results show that the synthesized shell-pearl type catalyst achieved 92.54% degradation efficiency of salicylic acid under 30 min UV irradiation, which is 1.97 times higher than that of TiO 2. The high degradation efficiency indicate that pearl type catalyst has promising applications in future environmental purification as well as human health. [Display omitted] • Successful synthesis of open shell-pearl structure photocatalyst. • The synthesized catalyst achieved 92.54% degradation efficiency of salicylic acid. • Imprinted molecules proved to have a protective effect. • The new structure-activity relationship has been fully demonstrated. [ABSTRACT FROM AUTHOR]

An 8-week feeding trial was proceeded to assess the effects of yeast and yeast extract on growth performance, anti-oxidant ability and intestinal microbiota of Litopenaeus vannamei. Five diets supplemented with 0% (Control), 3% beer yeast (Y), 0.5% yeast extract (YE0.5), 1% yeast extract (YE1) and 2% yeast extract (YE2) respectively were assigned to L. vannamei (four replicates per diet, 30 shrimp in each replicate, initial body weight 1.38 ± 0.01 g). The results showed higher weight gain and specific growth rate in shrimp fed diet YE2 compared with those fed the Control (P <.05). Both dietary yeast and yeast extract increased condition factor of shrimp (P <.05). Whole body moisture was significantly lower in shrimp fed yeast and yeast extract than those fed diet Control (P <.05). Shrimp fed yeast extract showed higher total antioxidant capacity compared to Control group (P <.05). Shrimp fed diet YE2 obtained higher catalase and glutathione peroxidase activities than those fed diet Control, YE0.5 and YE1 (P <.05). The main phyla in intestine of shrimp were Tenericutes, Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. With the increasing dietary yeast extract supplementation, the relative abundances of Ruegeria , and its belonging Rhodobacteraceae, Rhodobacterales, Alphaproteobacteria, Proteobacteria in intestine increased gradually, which were significantly higher than those fed diet Control and Y (P <.05). Moreover, yeast and yeast extract significantly increased the Shannon indexes of intestinal microbiota (P <.05). Overall, dietary 2.0% yeast extract supplementation significantly increased growth performance and antioxidant ability of shrimp, also enhanced microbial diversity and microbiota structure in intestine of L. vannamei. • The first time to reveal the effect of yeast extract on intestinal microbiota of L. vannamei. • 2% yeast extract supplemented improved growth performance and anti-oxidative ability of L. vannamei significantly. • Both yeast and yeast extract enhanced the stability of bacterial community in intestine of shrimp. • Yeast extract optimized microbiota structure by the increase of beneficial bacteria and decrease of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

• Legal aquaculture dose of SMX increased weight gain of Micropterus salmoides. • SMX increased the malformation rate of Micropterus salmoides. • SMX increased oxidative stress and inflammation of Micropterus salmoides. Antibiotics have been widely used (mainly mixed with feed) in aquaculture, while few studies have evaluated the interactions between feed composition and antibiotics. Sulfamethoxazole (SMX) is a fat-soluble antibiotic, an eight weeks feeding trial was conducted to investigate the interactions between dietary lipid levels and chronic exposure of legal aquaculture dose of sulfamethoxazole in juvenile largemouth bass Micropterus salmoides , and evaluated the possible human health risk. Six practical diets were formulated to three levels of crude lipid (11, 14.5, 18 %) and two levels of SMX (0 and 0.3 %), namely low fat (LF), moderate fat (MF), high fat (HF), low fat and SMX (LFS), moderate fat and SMX (MFS), high fat and SMX (HFS), respectively. Each diet was assigned to three tanks (20 fish per tank, average weight 30.65 ± 0.02 g). Growth and organ indices were increased by SMX. Higher malformation rate and lower hypoxia stress resistance were found in fish exposed to SMX than those not exposed. Cholesterol and bile acid synthesis related gene expressions were down-regulated by SMX exposure. Oxidative stress, inflammation and apoptosis were increased in fish exposed to SMX. Significant interactions between dietary lipid levels and SMX on renal immune response of fish were observed. Remarkable damage of intestinal histology was observed in fish fed the diet HFS. In addition, dietary SMX exposure increased pathogen susceptibility of largemouth bass and induced dysbiosis of gut microbiota. The concentrations of SMX in muscle of fish fed diets containing SMX were higher than those fed other diets, and close to the maximum residue limit (MRL) in China and international organizations. Although chronic legal aquaculture dose of dietary SMX also increased the target hazard quotient (THQ) and estimated daily intake (EDI), there is no health risk in adults and children consuming fish filet. [ABSTRACT FROM AUTHOR]

• A novel expansion planning model for urban integrated energy system is proposed. • The transportation network is incorporated into the model, in which fast and slow charging modes are considered. • A layered-based framework for the optimization model of the urban integrated energy system is proposed. • A two-layer optimization algorithm is designed to solve the proposed model. • Simulation results based on a real case in China indicate the superiority of the proposed approach. In the modern metropolitan regions, the coupling among distribution networks (DNs), gas networks (GNs), and transportation networks (TNs) is increasingly intensified, which gives rise to the urgent demand for efficient modeling and solving methods. In this context, a mathematical model for the configuration planning of integrated energy systems is proposed in this paper. With the aim of minimizing total planning costs, the model jointly considers the investment and operation strategies for distribution lines, distributed wind power generators (DWGs), combined heat and power units (CHPs), power to gas units (P2Gs), gas furnaces (GFs), fast charging facilities (FCFs) and slow charging facilities (SCFs). Since the proposed model comes down to a non-convex and nonlinear optimization problem, a two-layer algorithm is designed to solve it. In the outer layer, a genetic algorithm (GA) is performed to obtain a set of individuals representing the investment decisions on distribution lines, DWGs, and FCFs, which will be delivered to the inner layer model. With fixed decision variables, the inner model optimizes the operating costs, charging profit coefficients, and strategies for DWGs and energy converters in a coordinated manner. A real urban area in China is employed in the numerical experiment, which corroborates the effectiveness of the proposed model and solution algorithm. [ABSTRACT FROM AUTHOR]

• The structure of urban multi-energy network is provided. • Three energy flows are generally defined and their convex relaxations are performed. • A mixed user equilibrium is applied to describe rational route and charging choices. • A two-stage bound-tightening algorithm is proposed to strengthen convex relaxations. The ever-growing interdependence among power distribution, natural gas networks and transportation infrastructure entails efficient and coordinated optimization techniques. This paper proposes an operational optimization model of urban multi-energy networks that encompasses the synergies among the above components, energy converters and electric vehicles. The proposed model defines and encapsulates three energy flows in a convex optimization problem. In the distribution network, the conic relaxation-based branch flow equation is employed to characterize the alternating current power flow. The static characteristics of gas flow are described via the Weymouth equation with convex envelop relaxations. In the transportation network, the traffic flow patterns associated with the interplay among routing and charging behaviors are studied. Since these behaviors are amenable to the Wardrop principle such that the travel cost cannot be reduced by unilaterally altering travel choice, a mixed user equilibrium model is established to describe the related traffic flows. Although the relaxation quality has been improved by deriving the tighter bounds of the variables, to date, bound-tightening approaches have not yet been effectively applied to multi-energy network problems. To strengthen convex relaxations, we enhance the proposed model with a two-stage approach. The first stage improves the variable bounds through sequential optimality-based bound contraction. The second stage iteratively and successively solves the model with a dynamic bound-tightening algorithm. Based on case studies, the interdependence among energy networks is discussed. In addition, the numerical experiments corroborate the solution quality and computational efficiency benefits of the proposed approach. [ABSTRACT FROM AUTHOR]

The uncertainty of wind power brings security and economic issues in active distribution networks. As an effective solution to these problems, the active/reactive optimization aims at minimizing the total operation cost and network loss by controlling multiple resources. This paper proposes a two-stage data-adaptive robust optimization model for the dynamic active-reactive power flow. The dynamic correlation between the uncertainties of active and reactive power is analyzed at two kinds of power factor modes of wind turbines and then is described by a linear affine decision rule. To characterize these uncertainties, a data-adaptive multi-band uncertainty set is constructed based on historical data, which allows the number of bands and the corresponding weight coefficients to be adjusted under different confidence levels. Subsequently, the conic relaxation and linearization techniques are performed to reformulate the robust optimization model as a mixed-integer second-order cone programming problem. A two-level solution framework, consisting of a column-and-constraint generation algorithm and an outer approximation algorithm, is employed to solve this problem. Simulation results on a modified IEEE 33-bus system indicate that the variable power factor mode is more suitable for describing the dynamic correlation than the constant power factor mode. Besides, the proposed model and method also show better practicality and solution efficiency than the existing ones. [ABSTRACT FROM AUTHOR]

• A novel structure of the smart multi-energy system is proposed. • Transportation, natural gas, and active distribution networks are jointly considered. • Integrated energy stations are served to achieve the synergies of various energies. • A mixed user equilibrium is developed to obtain both routing and charging guidance. As the energy demand for multiple purposes increases, smart multi-energy systems have become the trend in the development of cities. In such an intelligent environment, it is possible and imperative to consider the traffic flow guidance for electric and non-electric vehicles in the urban transportation network. However, this has not yet been considered in the challenges of planning multi-energy systems. Based on these considerations, a novel optimal planning framework is proposed in the present study, that takes into account the coupling of transportation, natural gas and active distribution networks. Firstly, a novel structure of integrated energy stations is proposed, which serves as coupling components where various sources of energy can be converted, distributed, and stored. The model optimizes the investment and operational strategies of renewable energy generation, energy converters, storage devices and charging facilities in a coordinated way. To capture the impact of traffic flow, a mixed user equilibrium state was established. Thus, the route selections for non-electric vehicles and the navigations of electric vehicles to charging facilities could both be incorporated into the model. Since the proposed planning model is a mixed-integer nonlinear program problem, convex relaxation was conducted to transform the model formulations into a mixed-integer second order cone program version. Finally, four cases were designed and tested in a practical urban area. The quantitative comparison revealed that unguided traffic flow will increase the traffic costs by more than 23%. Moreover, when both charging and routing guidance are considered the energy losses will decrease by at least 5.6%. [ABSTRACT FROM AUTHOR]

• Based on survival, the optimal dietary protein level for post larval white shrimp was 49.58 %. • Shrimp fed the optimal dietary protein obtained the highest expression of TOR gene. • Shrimp fed the optimal dietary protein obtained the highest expression of two important initiation factors: eIF4E and eIF3k. A 25-days experiment was conducted to evaluate the effect of dietary protein levels on growth, survival, digestive enzymes and protein synthesis of post-larval Litopenaeus vannamei. Post-larval white shrimp (mean initial weight 2.1 mg) were fed five isoenergic diets containing gradient levels of protein (456, 469.9, 484.6, 501.4, 512.9 g/kg). Results indicated that 501.4 g/kg dietary protein increased the survival of post-larval white shrimp. Special growth rate (SGR) and weight gain (WG) showed no difference among each group. Whole body protein contents increased with the dietary protein increased to 484.6 g/kg. The relative mRNA levels of trypsin and chymotrypsin also increased with the dietary protein increased to 484.6 g/kg. Target of Rapamycin (TOR) and eukaryotic translation initiation factor 4E-binding protein (4EBP) mRNA expressions were significantly higher in shrimp fed the 484.6 g/kg dietary protein than other groups. The mRNA expression of two important translation initiation factors eukaryotic translation initiation factor 4E (eIF4E) and eukaryotic translation initiation factor 3k (eIF3k) were increased with the increasing dietary protein levels. Three endoplasmic reticulum (ER) stress related genes (eIF2α, XBP1 and ATF4) expression also increased with the dietary protein increased to 484.6 g/kg. These results clearly indicated that proper dietary protein improved the survival, and enhanced the protein synthesis of post larval white shrimp. Quadratic regression analysis based on survival indicated that the optimal dietary protein level of post-larval white shrimp was 495.8 g/kg. [ABSTRACT FROM AUTHOR]

• A two-stage robust planning model for the coupled system is proposed. • The uncertainty of renewable energy, load and traffic demand are jointly considered. • The interactions between transportation and active distribution system are explored. • A two-level method is used to solve the proposed robust optimization model. Widespread utilization of electric vehicles has incurred more uncertainties and led to profound interdependencies across the power grid and transportation network. This creates an urgent demand for uncertainty modelling tools. Under this context, this paper proposes a two-stage robust optimization model for expansion planning of coupled active distribution and transportation. This model identifies the best type, location and capacity for roads, distribution lines, distributed generations, static VAR compensators, on-load tap changers, energy storage systems and charging facilities. From a system-level perspective, the steady-state pattern of the traffic flow in a transportation network is characterized by the Wardrop user equilibrium. In the active distribution system, the conic relaxation-based branch flow equations are employed, and the operating status of related devices are formulated by the linearized convex constraints. Considering the interdependency between two coupled systems, a deterministic expansion planning model is first established. Furthermore, with multiple uncertainties considered, a two-stage robust optimization model is proposed to optimize the investment and operation strategies coordinately, and thus a robust optimal solution is achieved. A two-level algorithm based on a combination of the column-and-constraint generation and outer approximation technique is developed for solving the two-stage model. The results demonstrate that the robust approach can effectively reduce the operation cost of coupled systems under the worst-case scenarios. Moreover, a comparative analysis indicates that operation costs in both systems increase linearly as the uncertainty level of traffic demand increases, while increasing that of the power load does not show an obvious change in the traffic operation cost. [ABSTRACT FROM AUTHOR]

• A novel expansion planning model for active distribution system with multiple active network managements is proposed. • Optimal load shedding is originally proposed and shows an obvious better stability performance in case study. • A SOCP approach and some linearization means are applied to solve the MINLP model. • A two-stage optimization algorithm is developed and proved to have great ability to solve this problem. • Simulation results based on a modified 37-bus system indicate the technical and economic superiority of the proposed model. In this paper, a new expansion planning model for an active distribution system considering multiple active network management schemes is proposed, where demand management considering the optimal load-shedding direction is innovatively introduced into the planning model. This model optimizes the investment decisions of all the infrastructures as well as the corresponding operational strategies in a coordinated manner. Therefore, the final solution is identified by the optimal type, location and size of the feeders, distributed generators, capacitor banks, static var compensators, voltage regulators, energy storage systems, and transformer substations. To incorporate the optimal load reduction into active network management, the optimal load-shedding direction is first introduced, and an iterative method is developed to compute it. On this basis, the coordination planning model of an active distribution system is established, and the operational strategy of all the active management devices is integrated into the expansion planning problem of an active distribution system. By applying the second-order cone relaxation method, the original mixed-integer nonlinear model is converted into a mixed-integer second-order cone programming model that be efficiently solved. Finally, a two-stage optimization algorithm is proposed to obtain the final solutions. Simulation results based on a 37-bus system and a 122-bus system corroborate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

• A planning model of coupled transportation and active distribution system is proposed. • Scenario generation technique is extended to incorporate traffic demand. • Scenario-based user equilibrium constraint is derived and embedded into the model. • A three dimensional piecewise method is designed to relax the bivariate expressions. • The importance of considering interdependencies of the coupled system is verified. The widespread utilization of electric vehicles has inspired the emerging trend of coupled transportation and distribution system, which entails the systematic methodologies to model the new planning problems. This paper proposes a scenario-based comprehensive expansion planning model for a coupled transportation and active distribution system. With the aim of minimizing the investment and operation costs, this model determines the best alternatives, locations and sizes for candidate assets, including traffic roads, distribution lines, distribution generators, capacitor banks, static var compensators, voltage regulators, energy storage systems and charging facilities, as well as their operation strategies. First, a generated scenario method is extended to incorporate the uncertainty of the traffic flow demand. Based on multiple scenarios, the steady-state distribution of traffic flow is characterized by the Wardrop user equilibrium principle, and the corresponding equivalent constraints are derived and incorporated into the model. For active distribution system, we formulate the operation constraints for related infrastructures. Considering the interdependency between the two systems, an expansion planning model is proposed, which simultaneously optimizes the investment and operation strategies. Due to the nonlinear nature of the model, we have developed a three-dimensional piecewise linear approximation and applied second order cone relaxation to reformulate the model as a mixed-integer second order conic program; thus, the global optimal solution can be found in a reasonable time frame. Results on a test system reveal that the variations of both systems have some influences on each other, indicating the significance of considering the interdependencies between transportation and active distribution system. [ABSTRACT FROM AUTHOR]