The dissolution of total suspended solids and treatment strategy of tailwater in a Litopenaeus vannamei recirculating aquaculture system

In recirculating aquaculture systems(RASs),the effective treatment of aquaculture tailwater is essential to maintain the health of the RAS.This study investigated the optimal time and method for tailwater treatment during three periods of the aquaculture of the Litopenaeus vannamei:nursery(0–26 d),middle(27–57 d),and later(57–104 d).The variation of several water parameters during the dissolution of total suspended solid(TSS)in tailwater,applied with the effects of ozone on the microorganism and water quality parameters were investigated.Results showed that the TSS concentrations in tailwater decreased with time,although not significantly(P>0.05),whereas total ammonia nitrogen(TAN),nitrite(NO-2-N),and nitrate(NO_(3)^(-)-N)increased significantly(P<0.05).Therefore,TSS should be removed from the tailwater as early as possible,being most optimal within 4 h.Ozone removed 38.24%–48.95%of TSS,17.78%–90.14%of TAN,and 87.50%–98.90%of NO-2-N after 4 h of treatment.However,it resulted in the significant accumulation of NO_(3)^(-)-N.Moreover,the total number of Vibrio and bacterial counts in aquaculture tailwater was reduced completely by ozone within 4 h.Thus,these results provided technical details and data support for the effective treatment of tailwater from shrimp RAS.

The Relationship between the Area of Aquaculture Pond and Purification Pond in Water Circulation Aquaculture System

The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. However, no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond. In this study, referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond, based on the general rules of water quality management in freshwater aquaculture system, a calculation mode was es- tablished to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system, which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the bal- ance between the ecological benefits and the economic benefits.

Application of CFD Modeling to Hydrodynamics of CycloBio Fluidized Sand Bed in Recirculating Aquaculture Systems

To improve the efficiency of a CycloBio fluidized sand bed(CB FSB) in removal of dissolved wastes in recirculating aquaculture systems, the hydrodynamics of solid-liquid flow was investigated using computational fluid dynamics(CFD) modeling tools. The dynamic characteristics of silica sand within the CB FSB were determined using three-dimensional, unsteady-state simulations with the granular Eulerian multiphase approach and the RNG k-ε turbulence model, and the simulation results were validated using available lab-scale measurements. The bed expansion of CB FSB increased with the increase in water inflow rate in numerical simulations. Upon validation, the simulation involving 0.55 mm particles, the Gidaspow correlation for drag coefficient model and the Syamlal-O'Brien correlation for kinetic granular viscosity showed the closest match to the experimental results. The volume fraction of numerical simulations peaked as the wall was approached. The hydrodynamics of a pilot-scale CB FSB was simulated in order to predict the range of water flow to avoid the silica sand overflowing. The numerical simulations were in agreement with the experimental results qualitatively and quantitatively, and thus can be used to study the hydrodynamics of solid-liquid multiphase flow in CB FSB, which is of importance to the design, optimization, and amplification of CB FSBs.

Numerical simulation of the hydrodynamics within octagonal tanks in recirculating aquaculture systems

A three-dimensional numerical model was established to simulate the hydrodynamics within an octagonal tank of a recirculating aquaculture system. The realizable k-e turbulence model was applied to describe the flow, the discrete phase model （DPM） was applied to generate particle trajectories, and the governing equations are solved using the finite volume method. To validate this model, the numerical results were compared with data obtained from a full-scale physical model. The results show that： （1） the realizable k-e model applied for turbulence modeling describes well the flow pattern in octagonal tanks, giving an average relative error of velocities between simulated and measured values of 18% from contour maps of velocity magnitudes; （2） the DPM was applied to obtain particle trajectories and to simulate the rate of particle removal from the tank. The average relative error of the removal rates between simulated and measured values was 11%. The DPM can be used to assess the self-cleaning capability of an octagonal tank; （3） a comprehensive account of the hydrodynamics within an octagonal tank can be assessed from simulations. The velocity distribution was uniform with an average velocity of 15 cm/s; the velocity reached 0.8 m/s near the inlet pipe, which can result in energy losses and cause wall abrasion; the velocity in tank corners was more than 15 cm/s, which suggests good water mixing, and there was no particle sedimentation. The percentage of particle removal for octagonal tanks was 90% with the exception of a little accumulation of 〈5 mm particle in the area between the inlet pipe and the wall. This study demonstrated a consistent numerical model of the hydrodynamics within octagonal tanks that can be further used in their design and optimization as well as promote the wide use of computational fluid dynamics in aquaculture engineering.

Effect of copper on the growth of shrimps Litopenaeus vannamei : water parameters and copper budget in a recirculating system

Shrimps( Litopenaeus vannamei) were intensively cultured in a recirculating aquaculture system for 98 days to investigate effects of 0.3 mg/L Cu on its performance, Cu budget, and Cu distribution. Shrimps in Cu-treated systems had greater mean final weight(11.10 vs 10.50 g), body length(107.23 vs 106.42 mm), survival rate(67.80% vs 66.40%), and yield(6.42 vs 5.99 kg/m 3), and lower feed conversion ratio(1.20 vs 1.29) than those in control systems but the differences were not significant. Vibrio numbers remained stable(10 4 –10 6 colony forming units/mL) in the rearing tanks of both control and treated systems. Total ammonium-N, nitrite-N, nitrate-N, pH, chemical oxygen demand, 5-day carbonaceous biochemical oxygen demand, and total suspended solids were similar in controls and treatments. Dissolved Cu concentration in the treated systems decreased from 0.284 to 0.089 mg/L while in the control systems it increased from 0.006 2 to 0.018 mg/L. The main sources of Cu in the treated systems were the artificially added component(75.7% of total input), shrimp feed(21.0%), water(2.06%), and shrimp biomass(1.22%). The major outputs of Cu occurred via the mechanical filter(41.7%), water renewal(15.6%), and draining of the sediment trap(15.1%). The foam fractionator removed only 0.69% of total Cu input. Harvested shrimp biomass accounted for 11.68% of Cu input. The Cu concentration of shrimps in the Cu-treated systems(30.70 mg/kg wet weight) was significantly higher than that in control systems(22.02 mg/kg). Both were below the maximum permissible concentration(50 mg/kg) for Cu in seafood for human consumption in China. Therefore, recirculating systems can be used for commercial on-growing of Litopenaeus vannamei without loss of shrimp quality, even in water polluted by 0.30 mg/L Cu. The mechanical filter is the main route for Cu removal.

Tracking Performance of Electric Power Steering System Based on the Mixed H_2/H_∞ Strategy

The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering （EPS） system. Bad tracking performance will cause assistant torque delay, and make road feeling bad, and is influenced by the input steering torque and system measuring noise. However the existing methods have some shortages on system＇s robust dynamic performance and robust stability. The mixed H2/H∞ strategy for recirculating ball-type EPS system in a pure electric bus is proposed, and vehicle dynamic model of the system is established. Due to the existence of system model uncertainty, disturbance signals, sensor noises and the demand of system dynamic performance, the indexes of robust performance and road feeling for drivers are defined as the appraisal control objectives. The H∞ method is introduced to design the H∞ controller, and the H2 method is applied to optimize the H∞ controller, thus the mixed H2/H∞ controller is designed. The response of EPS system to the motor current command with amplitude of 20 A, the road disturbance with amplitude of 500 N and the sensor random noise with the amplitude of 1 A is simulated. The simulation results show that the recirculating ball-type EPS system with the mixed H2/H∞ controller can attenuate the random noises and disturbances and track the boost curve well, so the mixed H2/H∞ controller can improve the system＇s robust performance and dynamic performance. For the purpose of verifying the performance of the designed control strategy, the motor current tracking performance ground tests are conducted with step response input of the steering wheel, double-lane steering test and lemniscate steering test, respectively. The tests show that the mixed H2/H∞ controller for the recirculating ball-type EPS system of pure electric bus is feasible. The designed controller can solve the robust performance and robust stability of the system, thus improve the tracking performance of the EPS system and provide satisfied road feeling for the drivers.

Intestinal microbiota of healthy and unhealthy Atlantic salmon Salmo salar L. in a recirculating aquaculture system

The present study sampled the intestinal content of healthy and unhealthy Atlantic salmon （Salmo salar L.）, the ambient water of unhealthy fish, and the biofilter material in the recirculating aquaculture system （RAS） to understand differences in the intestinal microbiota. The V4--V5 regions of the prokaryotic 16S rRNA genes in the samples were analyzed by MiSeq high-throughput sequencing. The fish were adults with no differences in body length or weight. Representative members of the intestinal microbiota were identified. The intestinal microbiota of the healthy fish included Proteobacteria （44.33%）, Actinobacteria （17.89%）, Baeteroidetes （15.25%）, and Firmicutes （9.11%）, among which the families Mierococcaceae and Oxalobacteraceae and genera Sphingomonas, Streptomyces, Pedobacter, Janthinobacterium, Burkholderia, and Balneimonas were most abundant. Proteobacteria （70.46%）, Bacteroidetes （7.59%）, and Firmicutes （7.55%） dominated the microbiota of unhealthy fish, and Chloroflexi （2.71%）, and Aliivibrio and Vibrio as well as genera in the family Aeromonadaceae were most strongly represented. Overall, the intestinal hindgut microbiota differed between healthy and unhealthy fish. This study offers a useful tool for monitoring the health status of fish and for screening the utility of probiotics by studying the intestinal microbiota.

Commercial Production of Tiger Puffer(Takifugu rubripes)in Winter Using a Recirculating Aquaculture System

Tiger puffer(Takifugu rubripes) is a promising species for aquaculture production because of its high value and limited supply. However, in the north of China, using sea cages to culture this species in winter is hampered by the fact that the seawater temperature is extremely low. Here, a large scale commercial production of tiger puffer has been successfully realized using a recirculating aquaculture system(RAS) from 3 October 2012 to 31 May 2013. The RAS was comprised of nine culture tanks(total water volume 200 m3) and stocked with approximately a total of 14400 fish(initial mean weight 160 g). The tiger puffer was hand-fed at a rate of 0.7% of total body weight per day, and the feed conversion rate was(1.21 ± 0.3) kg kg-1. The recycle water in RAS was treated by a sieve bend screen, a foam fractionator, a submerged biofilter, an UV sterilizer and a submersible aerator. During the whole culture period, an excellent water quality control was achieved in RAS. At the end of this experiment, the survival rate of tiger puffer was more than 98%. The final tank densities averaged 31.2 kg m-3, and the final individual mean weight was 440 g.

Effect of Hydraulic Loading Rate on the Efficiency of Effluent Treatment in a Recirculating Puffer Aquaculture System Coupled with Constructed Wetlands

Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions(salinity 7.4–7.6) at 3 different HLRs(0.762, 0.633, and 0.458 m d–1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen(by 81.03–92.81%) and nitrite nitrogen(by 99.40%–99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids(TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.

Effect of Prometheus liver assist system on systemic hemodynamics in patients with cirrhosis: A randomized controlled study

AIM： To evaluate treatment safety and hemodynamic changes during a single 6-h treatment with the PrometheusTM liver assist system in a randomized, controlled study. METHODS： Twenty-four patients were randomized to either the study group or to one of two control groups： Fractionated Plasma Separation Adsorption and Dialysis, PrometheusTM system （Study group; n = 8）; Molecular Adsorbent Recirculation System （MARS）TM （Control group 1, n = 8）; or hemodialysis （Control group 2; n = 8）. All patients included in the study had decompensated cirrhosis at the time of the inclusion into the study. Circulatory changes were monitored with a Swan-Ganz catheter and bilirubin and creatinine were monitored as measures of protein-bound and water-soluble toxins. RESULTS： Systemic hemodynamics did not differ between treatment and control groups apart from an increase in arterial pressure in the MARS group （P = 0.008）. No adverse effects were observed in any of the groups. Creatinine levels significantly decreased in the MARS group （P = 0.03） and hemodialysis group （P = 0.04）. Platelet count deceased in the Prometheus group （P = 0.04）.CONCLUSION： Extra-corporal liver support with Prometheus is proven to be safe in patients with endstage liver disease but does not exert the beneficial effects on arterial pressure as seen in the MARS group,

Effects of spectral composition,photoperiod and light intensity on the gonadal development of Atlantic salmon Salmo salar in recirculating aquaculture systems(RAS)

Artificial lighting regimes have been successfully used to inhibit sexual maturity of Atlantic salmon in confinement.However,when these operations are applied in commercial recirculating aquaculture systems(RAS) using standard lighting technology,sexual maturation is not suppressed.In this study,an L_9(3~3) orthogonal design was used to determine the effects of three factors(spectral composition,photoperiod,and light intensity) on the gonadal development of Atlantic salmon in RAS.We demonstrated that the photoperiod at the tested levels had a much greater effect on the gonadosomatic index and female Fulton condition factor than spectral composition and light intensity.The photoperiod had a significant effect on the secretion of sex steroids and melatonin(P<0.05),and a short photoperiod delayed sex steroid and melatonin level increases.The three test factors had no significant effects on the survival rate,specific growth rate,relative weight gain,and male Fulton condition factor(P>0.05).The optimum lighting levels in female and male Atlantic salmon were LD 8:16,455 nm(or 625 nm),8.60 W/m^2;and LD 8:16,8.60 W/m^2,455 nm respectively.These conditions not only delayed gonadal development,but also had no negative effects on Atlantic salmon growth in RAS.These results demonstrate that a combination of spectral composition,photoperiod and light intensity is effective at delaying the gonadal development of both male and female salmon in RAS.

Total Replacement of Fish Oil with Vegetable Oils in the Diet of Juvenile Jade Perch Scortum barcoo Reared in Recirculating Aquaculture Systems

To determine the replacement of fish oil with vegetable oils in the diet of juvenile Jade perch Scortum barcoo, four feeds with each a different oil （fish, sunflower, linseed and a mixture of 75% canola and 25% linseed oil）, were fed to Jade perch reared in recirculating aquaculture systems （RAS）. The trial lasted for 10 weeks and the fatty acid （FA） profile of both feed and fish muscle tissue were examined. There was no difference in growth, feed conversion rate （FCR） and mortality. The fish grew from 10 g to 110 g with a FCR of 1.25 and 0 mortality. The FA profile of the fish muscle tissue reflected the FA profile of the feed. The flesh of the fish that were fed the linseed oil diet, were extremely high in omega-3 （n-3） polyunsaturated FA （n-3 PUFA） with 3.75% of wet weight. This is one of the highest concentrations of n-3 PUFA ever recorded in fish flesh. In a finishing feeding test, the remaining vegetable oil fed fish were fed the fish oil diet for another two weeks immediately after the 10 weeks trial, to check for a possible recovery of n-3 highly unsaturated fatty acids （HUFA）. The wash out rate of FA towards n-3 HUFA in the muscle tissue was about 25% over this two weeks period.

Survival predictors in patients treated with a molecular adsorbent recirculating system

AIM:To identify prognostic factors for survival in patients with liver failure treated with a molecular adsorbent recirculating system(MARS). METHODS:MARS is a liver-assisting device that has been used in the treatment of liver failure to enable native liver recovery,and as a bridge to liver transplantation(LTX).We analyzed the 1-year outcomes of 188 patients treated with MARS,from 2001 to 2007, in an intensive care unit specializing in liver disease. Demographic,clinical and laboratory parameters were recorded before and after each treatment.One-year survival and the number of LTXs were recorded.Logistic regression analysis was performed to determine factors predicting survival. RESULTS:The study included 113 patients with acute liver failure(ALF),62 with acute-on-chronic liver failure(AOCLF),11 with graft failure(GF),and six with miscellaneous liver failure.LTX was performed for 29% of patients with ALF,18% with AOCLF and 55%with GF.The overall 1-year survival rate was 74% for ALF,27% for AOCLF,and 73% for GF.The poorest survival rate,6%,was noted in non-transplanted patients with alcohol-related AOCLF and cirrhosis,whereas,patients with enlarged and steatotic liver had 55% survival.The etiology of liver failure was the most important predictor of survival(P<0.0001).Other prognostic factors were encephalopathy(P=0.001)in paracetamol-related ALF, coagulation factors(P=0.049)and encephalopathy(P=0.064)in non-paracetamol-related toxic ALF,and alanine aminotransferase(P=0.013)and factor V levels(P =0.022)in ALF of unknown etiology. CONCLUSION:The etiology of liver disease was the most important prognostic factor.MARS treatment appears to be ineffective in AOCLF with end-stage cirrhosis without an LTX option.

Submarine groundwater discharge enhances primary productivity in the Yellow Sea, China: Insight from the separation of fresh and recirculated components

Submarine groundwater discharge(SGD)is being increasingly recognized as a significant source of nutrient into coastal waters,and generally comprises two components:submarine fresh groundwater discharge(SFGD)and recirculated saline groundwater discharge(RSGD).The separate evaluation of SFGD and RSGD is extremely limited as compared to the conventional estimation of total SGD and associated nutrient fluxes,especially in marginal-scale regions.In this study,new high-resolution radium isotopes data in seawater and coastal groundwater enabled an estimation of SGD flux in a typical marginal sea of the Yellow Sea.By establishing 226Ra and 228Ra mass balance models,we obtained the SGD-derived radium fluxes,and then estimated the SFGD and RSGD fluxes through a two end-member model.The results showed that the total SGD flux into the Yellow Sea was equivalent to approximately 6.6 times the total freshwater discharge of surrounding rivers,and the SFGD flux accounted for only 5.2%–8.8%of the total SGD.Considering the nutrient concentrations in coastal fresh and saline groundwater,we obtained the dissolved inorganic nutrient fluxes(mmol m^(-2) yr^(-1))to be 52–353 for nitrogen(DIN),0.21–1.4 for phosphorus(DIP),34–226 for silicon(DSi)via SFGD,and 69–262 for DIN,1.0–3.9 for DIP,70–368 for DSi via RSGD,with the sum of nutrient fluxes equaling to(1.8–9.3)-fold,(1.3–5.6)-fold and(2.0–9.5)-fold of the riverine inputs.Compared to the conventional estimation of the total SGD flux,the nutrient fluxes derived from the separation of SFGD and RSGD were(1.6–2.1),(1.6–1.8)and(4.0–4.9)times lower for DIN,DIP and DSi,respectively,indicating that the estimates by separating SFGD and RSGD could be conservative and representative results of the Yellow Sea.Furthermore,we suggested that SGD played an important role in nutrient sources among all the traditional nutrient inputs sources,providing 15%–48%,33%–68%and 14%–43%of the total DIN,DIP and DSi input fluxes into the Yellow Sea,and the high nutrient stoichiometric ratios(i.e.,DIN/DIP)in SGD probably contributed to the increasing ratios in the Yellow Sea.In addition delivering large amounts of nutrient into the Yellow Sea,SGD would create primary productivity of 10–49,1.6–6.8 and 8.8–42 g C m^(-2)yr^(-1) based on N,P and Si,which were equivalent to 5.2%–27%,0.9%–3.7%and 4.7%–23%of the total primary productivity,respectively.In particular,the SFGD-derived DIN flux can be converted to primary productivity of 4.2–28 g C m^(-2)yr^(-1) thus demonstrating the disproportionately large role of SFGD in ecological environment of the Yellow Sea relative to its flux.Therefore,we conclude that SGD,particularly SFGD,plays an important role as a nutrient source for the Yellow Sea,and not only affects nutrient budgets and structures but also enhances the primary productivity.

Effects of Nutrients on Biofouling Formation and Preponderant Bacteria Diversity in Recirculating Cooling Water System

A series of orthogonal array experiments were conducted using carbon source, ammonia nitrogen and total phosphorus （TP） as major influencing factors to investigate the effects of nutrients on biofouling formation and preponderant bacteria diversity in the recirculatiug cooling water system. Carbon source was demonstrated to be the most significant determinant affecting the biofouling formation. A minimum biofouling outcome was obtained when BOD2, NHa＋-N and TP were 25, 10, and 1 mg/L, respectively. Then the preponderant bacteria strains in biofouling mass under two typical culture conditions （negative and favorable） were identified applying both traditional biochemical methods and further molecular biology technology with phylogenetic affiliation analysis, which indicated that Enterobacteriaceae Enterobacter, Micrococcaceae Staphylococcus, Bacillaceae Bacillus, Enterobacteriaceae Proteus, Neisseriaceae Neisseria and Pseudomonadaceae Pseudomonas were dominant under negative condition, while Enterobacteriaceae Klebsiella, Enterobacteriaceae Enterobacter and Microbacterium - under favorable one.

Characterization of Bacterial Community,Ammonia-Oxidizing Bacteria,and Nitrospira During the Operation of a Commercial-Scale Recirculating Aquaculture System for Culturing Pufferfish Takifugu rubripes

We investigated the changes in communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira during the operation of a pufferfish Takifugu rubripes recirculating aquaculture system by using high-throughput DNA sequencing.Differences in bacterial communities were observed at days 1-32,47-62 and 78-93 of biofilm development by using 16S rRNA gene pyrosequencing.The relative abundance of Proteobacteria(Gammaproteobacteria)increased,while that of Bacteroidetes(Flavobacteria)decreased.The proportions of Nitrosomonas and Nitrospina ranged from 0.02%to 0.30%and from 0.02%to 0.83%,respectively.Ammonia monooxygenase gene pyrosequencing revealed that the top three operational taxonomic units were related to Nitrosomonas aestuarii(17.5%-61.1%),uncultured beta proteobacterium clone B67S-54(1.9%-45.2%),and uncultured bacterium clone AZPa8(3.6%-24.7%).Nitrite oxidoreductase gene pyrosequencing revealed that the relative abundance of the dominant strain Nitrospira sp.Ecomares 2.1 increased,but that of the abundant species Nitrospira marina decreased.Our results demonstrated that the communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira were changing during the operation of the pufferfish recirculating aquaculture system.

Characterization of the bacterial communities associated with biofilters in two full-scale recirculating aquaculture systems

Bacteria play a major role in metabolizing ammonia and other metabolites in recirculating aquaculture systems(RASs).To characterize and compare the bacterial communities in the biofilters of two full-scale RASs for the culture of puffer fish,Takifugu rubripes,at different ages and densities were studied.In overall,47807 optimized reads of the 16 S rRNA gene with V4-V5 region were obtained from four biofilm samples collected after biofilm maturation.At 97%cut-off level,these sequences were clustered into 500 operational taxonomic units,and were classified into 19 bacterial phyla and 138 genera.At the phylum level,Proteobacteria and Bacteroidetes were the most abundant,followed by Nitrospirae and Planctomycetes.At the genus level,Colwellia,Marinifilum,Oceanospirillum,Lutibacter,Winogradskyella,Pseudoalteromonas,Arcobacter,and Phaeobacter were the top members.Nitrosomonas and Nitrospira were main ammonia-and nitrite-oxidizing bacteria.Differences in bacterial communities at different sampling dates and similarities of both biofilters were revealed in the Venn diagram and cluster analysis.Maintaining a good water quality and health offarmed fish in RASs depended on the correct management of the bacterial communities.This study provides more accurate information on the bacterial communities associated with the bifilters of both RASs.

Artificial liver support molecular adsorbents recirculating system therapy as a bridge to re-transplantation in two cases of long anhepatic duration

BACKGROUND: Molecular adsorbents recirculating sys- tem (MARS) liver support therapy is the development of albumin dialysis. This study was to assess the successful ap- plication of MARS artificial liver support therapy as a bridge to re-transplantation in two cases of long anhepatic duration. METHODS: MARS therapy was given after failure plasma- exchange ( PE) treatment, which resulted in circulatory de- rangement and acute renal dysfunction in a 36-year-old male patient. Finally his uncontrolled anhepatic condition led to a successful re-transplantation. In another 48-year- old man who was diagnosed as having primary nonfunction (PNF) during the liver transplantation, 10-hour MARS treatment contributed to smooth bridging of his anhepatic phase. RESULTS: The two anhepatic patients were bridged for 26 and 17 hours respectively to re-transplantation with MARS therapy. CONCLUSION: Our experience proves that MARS artifi- cial liver can be an effective support for long time bridging PNF until re-transplantation is available.

Stocking density effects on growth and stress response of juvenile turbot(Scophthalmus maximus) reared in land-based recirculating aquaculture system

Stocking density is widely recognized as a critical factor in aquaculture and a potential source of long-term stress.The influence of stocking density on growth and stress response of juvenile turbot（Scophthalmus maximus, ~3–75g, initial to final weight） was examined in fish held under low（LD, ~0.21–5.31 kg/m^2, initial to final density）,medium（MD, ~0.42–10.81 kg/m^2） and high stocking density（HD, ~0.63–14.27 kg/m^2） for 120 days in a recirculating aquaculture system（RAS）. In this trial, the growth curve for weight of juvenile turbot in RAS, all fitted by the Schnute model. No significant difference was found in growth performance among the three densities until at the final sampling（Day 120）. The final weight and body weight increase（BWI） in the HD group were significantly lower than in other groups（P〈0.05, weight：（75.83±2.49） g,（75.39±2.08） g,（65.72±2.86） g and BWI：（2 436.12±28.10）%,（2 421.29±4.64）%,（2 097.88±20.99）% in LD, MD and HD groups, respectively）. Similarly, the specific growth rate（SGR）, feed conversion ratio（FCR） and coefficient of variation for weight（CV_w） were adversely affected by high stocking density（P〈0.05）. However, there was no difference in survival and Fulton＇s condition factor（K） of turbot among the different groups. Physiological analyses demonstrated a clear increase in the plasma cortisol level and an obvious decrease in growth hormone（GH） concentration in the HD group on Day120（P〈0.05）. There was no significant effect of stocking density on plasma glucose, Cl– and protein levels. All these findings would provide a reference for selecting the optimal stocking density of juvenile turbot in RAS.

Variability of the Kuroshio extension system in 1992-2013 from satellite altimetry data

The Kuroshio Extension （KE） plays an important role in climate and environmental change in the North Pacific. In this paper, more than 20 years of merged absolute dynamic topography and merged sea level anomaly products from satellite altimetry are used to analyze the stability of the KE system. By analyzing the annually averaged sea surface topography, the variations of inter-annual path and annually averaged eddy kinetic energy at the KE region, the KE＇s two dynamic states are given as： the relatively stable state during 1993 1995, 2002-2005, and 2010-2012, and the unstable dynamic state among 1996-2001 and 2006-2009. During the stable state, the KE spindle had a shorter path length and smaller time-varying amplitude, as well as a trend to move northward. While during the unstable state, the KE spindle had a longer path length and an integral southward transport trend, and was observed to oscillate significantly over time. The analysis on the KE＇s upstream and downstream region gives the same variations, indi- cating that they are significantly affected by the El Nino events. The power spectrum of the mean latitudinal position variation of the KE＇s upstream and downstream shows significant quasi-decadal oscillation characteristics and strong annual signals. Furthermore, the correlation of the strength vari- ation between the southern RG and the KE＇s upstream is calculated to be 0.50 after low-pass filtering, and that of the mean latitudinal position variation between the southern RG and the KE＇s upstream/ downstream are 0.75/0.69 after low-pass filtering, respectively. The strong correlations demonstrated that the southern RG and the KE are closely linked.