The density and volumetric behavior of three typical n-alkanes (hexane, octane, and decane) influenced by different mole fractions of CO2 injected in them at temperatures from 303 to 363 K and pressures from 3.8 to 8.67 MPa were investigated by performing molecular dynamics simulations. It is shown that the mass density first increases and then decreases with increasing CO2 mole fraction. Correspondingly, the system volume only slightly swells at low CO2 contents while suddenly expanding when the CO2 mole fraction exceeds a value of ∼60%. The calculations of structural properties and interaction energies indicate that at low CO2 mole fractions, there are a few CO2 molecules existing in the gap of alkane molecules, resulting in poor compressibility, while at higher CO2 concentrations, the CO2 molecules begin to separate from the CO2-saturated alkane phase and form a gas phase, leading to higher compressibility. Therefore, at high CO2 mole fractions, the system density and volume can more easily be changed by temperature and pressure than that at low CO2 mole fractions. In addition, since it is harder for alkanes with longer chains to separate from each other, the volume swelling decreases and the density increases with increasing carbon number of n-alkane chains. Finally, we found that the increase in CO2 mole fraction, temperature, and the decrease in alkane chain length would promote the diffusion of both CO2 and alkane molecules. However, the influence of pressure on molecular diffusion is very limited except when P = 8.67 MPa and T = 333 K, where CO2 is in the supercritical state. This work is helpful for understanding the density and volumetric behavior of n-alkane/CO2 mixtures at a molecular level and provides useful information for guiding carbon sequestration and CO2-enhanced oil recovery.

Driven by rapid ongoing advances in humanoid robot, increasing attention has been shifted into the issue of emotion intelligence of AI robots to facilitate the communication between man-machines and human beings, especially for the vocal emotion in interactive system of future humanoid robots. This paper explored the brain mechanism of vocal emotion by studying previous researches and developed an experiment to observe the brain response by fMRI, to analyze vocal emotion of human beings. Findings in this paper provided a new approach to design and evaluate the vocal emotion of humanoid robots based on brain mechanism of human beings.

<正>青鱼养殖在江浙一带十分普遍。常见的青鱼养殖模式通常采用螺蛳加沉性颗粒饲料的投喂方式,这种养殖方式饲料系数一般在3～4;另外,由于青鱼养殖密度较高,容易导致水体富营养化和病害的发生,在一定程度

Multidrug-resistance associated protein 2 (MRP2/ABCC2) plays crucial roles in bile formation and detoxification by transporting a wide variety of endogenous compounds and xenobiotics, but its functions in zebrafish (Danio rerio) remain to be characterized. In this study, we obtained the full-length cDNA of zebrafish abcc2, analyzed its expression in developing embryos and adult tissues, investigated its transcriptional response to heavy metals, and evaluated its roles in efflux of heavy metals including cadmium, mercury and lead. Zebrafish abcc2 gene is located on chromosome 13 and composed of 32 exons. The deduced polypeptide of zebrafish ABCC2 consists of 1567 amino acids and possesses most of functional domains and critical residues defined in human ABCC2. Zebrafish abcc2 gene is not maternally expressed and its earliest expression was detected in embryos at 72hpf. In larval zebrafish, abcc2 gene was found to be exclusively expressed in liver, intestine and pronephric tubules. In adult zebrafish, the highest expression of abcc2 gene was found in intestine followed by those in liver and kidney, while relative low expression was detected in brain and muscle. Expression of abcc2 in excretory organs including kidney, liver and intestine of zebrafish larvae was induced by exposure to 0.5μM mercury or 5μM lead. Moreover, exposure to 0.125-1μM of mercury or lead also significantly induced abcc2 expression in these excretory organs of adult zebrafish. Furthermore, overexpression of zebrafish ABCC2 in ZF4 cells and zebrafish embryos decreased the cellular accumulation of heavy metals including cadmium, mercury and lead as determined by MRE (metal responsive element)- or EPRE (electrophile response element)-driven luciferase reporters and atomic absorption spectrometry. These results suggest that zebrafish ABCC2/MRP2 is capable of effluxing heavy metals from cells and may play important roles in the detoxification of toxic metals.

一、池塘条件 养殖池塘由主养鱼塘和辅养鱼塘组成,面积比为2:3;要求靠近水源,进排水方便,通电和水陆交通便利.主养池塘5～20亩均可,平均水深1.5～1.8米,池底平坦,淤泥厚度应小于30厘米.辅养池塘可由多个池塘组成,水深在1.2～2.0米均可;辅养池塘周边种植30～50厘米宽的芦苇或藕等挺水植物带,池中种植水菱、水葫芦等漂浮植物,分隔成团块状平均分布于池塘中,种植水生植物的面积以总水面的15%～20%为宜;池底淤泥不宜超过15厘米.

An 8-week laboratory trial was designed to study the effect of phytase on growth,body composition and phosphorus content in tissues of juvenile grass carp（C.idellus） fed plant protein based diet.Seven trial diets were formulated to feed fish（with mean initial body weight of 39.68±3.05 g） that were divided into 5 experimental groups and 2 control groups.Five triplicate experimental groups were supplemented with five different levels of phytase（500 U/kg,750 U/kg,1 000 U/kg,1 250 U/kg,2 500 U/kg）.The positive control group was supplemented with 1.5% monobasic calcium phosphate;and the negative control group was not supplemented with phytase and monobasic calcium phosphate.Through 60 d experiment,the effects of phytase were examind on growth,body composition and phosphorus content in tissues of juvenile grass carp（C.idellus）fed plant protein based diet.The results showed that,the feed conversion rate（FCR） was significantly lower,whereas protein efficiency ratio（PER） and specific growth rate（SGR） were significantly higher than those of other groups（P0.05）,when only monobasic calcium phosphate was supplemented.Compared with negative control group,after added phytase in diet,when the supplemented level of phytase was higher than 1 000 U/kg,the FCR of experimental group 3（1 000 U/kg） was significantly lower than that of negative control group（P0.05）,and PER was significantly higher than that of negative control group（P0.05）;The phytase has no effcets on the HSI,VSI,and CF of fish;the content of crude fat decreased in body,when the phytase content was higher than 1000U/kg,when the supplemented level of phytase content was 1 000 U/kg,the crude fat in muscle was significantly improved;The phosphorus content was enhanced to some degree in body,muscle and spine after added phytase,and when the content was 1 250 U/kg,the phosphorus content were significantly improved in muscle and spine.The result indicated that,when the supplemented level of phytase was 1 000 U/kg-1 250 U/kg,the SGR,PER and phosphorus content of grass carp were enhanced,and FCR was improved compared with negative control group.If you want to reduce the supplemented level of monobasic calcium phosphate,the suitable supplemented level of phytase was 1 000 U/kg-1 250 U/kg.

挑选体重为(10.49±0.13)g健康的中华绒螯蟹180只,平均分成6组,每组3个重复,分别饲喂含0、0.25× 109、0.5×109、1×109、2×109、4×109 cfu/kg枯草芽孢杆菌的饲料,进行8周的生长试验,以探讨芽孢杆菌对中华绒螯蟹生长性能及体成分的影响.试验结果表明,随着枯草芽孢杆菌添加量的增加,中华绒螯蟹的生长呈现先上升后下降的趋势,当饲料中添加1×109 cfu/kg时增重和特定生长率最大,且显著高于其他各组(P＜0.05)；通过方差分析,各个组全蟹的水分、粗脂肪、粗蛋白、粗灰分差异不显著(P＞0.05)；添加枯草芽孢杆菌试验组能降低肝体指数,1×109 cfu/kg组的肝体指数最小,且显著小于对照组(P＜0.05).由此可见,饲料中添加适宜的枯草芽孢杆菌可显著提高中华绒螯蟹的生长,且不会明显改变全蟹的营养成分组成,适宜添加量为1×109 cfu/kg.

An 8-week experiment on fingerling black carp Mylopharyngodon piceus was conducted to evaluate the effects of dietary fish oil (FO) supplement on growth, fatty acid composition and non-specific immunity responses. Five triplicate fingerling groups (initial weight = 2.72 +/- 0.35 g) were fed isoenergetic and isonitrogenous diets in which the dietary FO was replaced with rapeseed oil (RO) in graded increments of 25% (0-100%). No significant effects were observed on specific growth rates, survival rates and feed conversion ratios, but there were significant differences in whole body moisture and liver lipid contents (P < 0.05), and the 100% RO replacement diet significantly enhanced hepatosomatic indexes compared to control group (P < 0.05). Other approximate whole body constituents, viscerasomatic ratios and condition factors were not influenced by dietary oil treatments. Fatty acid composition of muscle and liver was influenced by dietary fatty acid input, alpha-linoleic acid and gamma-linolenic acid were significantly increased with increasing RO, but eicosapentaenoic acid, docosahexaenoic acid and the n-3/n-6 ratio were significantly reduced (P < 0.05). Alternative complement pathway, lysozyme and superoxide dismutase activities were not significantly influenced. These results indicate that black carp fed diets with FO supplement had similar growth and non-specific immunity to the fish fed diet with RO.

对全红、花红、粉色和粉花4种体色的瓯江彩鲤肌肉中的粗蛋白、粗脂肪、灰分、水分、矿物质和氨基酸含量进行了测定.结果表明:4种彩鲤肌肉水分分别为77.81%、77.71%、77.36%和77.85%,粗蛋白含量分别为19.43%、20.14%、19.66%和19.44%,粗脂肪含量分别为1.67%、1.64%、1.65%和1.71%,灰分含量分别为1.41%、1.41%、1.44%和1.41%;4种体色瓯江彩鲤肌肉均富含钙、镁、铁、铜和锌等5种矿物元素含量,且氨基酸含量和必需氨基酸总量较高,氨基酸总量分别为77.99%、77.72%、77.62%和77.86%,必需氨基酸总量分别为32.85%、33.3%、33%和32.95%.经方差分析,4种不同体色的瓯江彩鲤肌肉粗蛋白、粗脂肪、灰分、水分和氨基酸及必需氨基酸总量均无显著差异,这表明,不同体色的瓯江彩鲤营养价值非常接近,均属于营养价值较高的经济鱼类.

Acquired resistance of mammalian cells to heavy metals is closely relevant to enhanced expression of several multidrug resistance-associated proteins (MRP), but it remains unclear whether MRP proteins confer resistance to heavy metals in zebrafish. In this study, we obtained zebrafish (Danio rerio) fibroblast-like ZF4 cells with resistance to toxic heavy metals after chronic cadmium exposure and selection for 6months. These cadmium-resistant cells (ZF4-Cd) were maintained in 5μM cadmium and displayed cross-resistance to cadmium, mercury, arsenite and arsenate. ZF4-Cd cells remained the resistance to heavy metals after protracted culture in cadmium-free medium. In comparison with ZF4-WT cells, ZF4-Cd cells exhibited accelerated rate of cadmium excretion, enhanced activity of MRP-like transport, elevated expression of abcc2, abcc4 and mt2 genes, and increased content of cellular GSH. Inhibition of MRP-like transport activity, GSH biosynthesis and GST activity significantly attenuated the resistance of ZF4-Cd cells to heavy metals. The results indicate that some of MRP transporters are involved in the efflux of heavy metals conjugated with cellular GSH and thus play crucial roles in heavy metal detoxification of zebrafish cells.

Three experiments were conducted to determine the lysine,methionine and arginine.requirements of juvenile Chinese mitten crab Eriocheir sinensis.The juvenile crab[average initial weight:Lys experiment(2.050±0.027)g;Methionine experiment(2.027±0.033)g;Arginine experiment(2.05±0.032)g]were fed amino acids test diets for 56 days with the protein source containing casein,white fishmeal,soybean meal and crystalline amino acids.The test diets contained 5 graded levels of lysine(1.58%,1.98%,2.38%,2.78% and 3.18%),methionine(0.50%,0.75%,1.00%,1.25% and 1.50%)and arginine(1.39%,2.09%,2.79%,3.49% and 4.19%)respectively.The triplicate feeding trials were conducted in fiberglass tanks indoor.Water temperature and pH were kept at(28±3.0)℃ and 7.4,respectively.The results of the lysine experiment showed crab fed diet 3 containing 2.38% lysine had the best weight gain(WG)and specific growth ratio(SGR),but no significant difference was found between the levels of 1.98%(diet 2)to 2.78%(diet 4);the whole crab fed diet 3 had significantly low moisture and significantly high protein content(P0.05).The results of methionine experiment showed crab fed diet 8 containing 1.00% methionine had significantly high WG and SGR(P0.05),no significant difference was found in other test groups;the crab fed diet 10(1.5% methionine)had significant high moisture content and low protein content of whole body(P0.05);no significant difference was found among the other test diets(diet 6 to diet 9).The results of arginine experiment showed crab fed diet 14 containing 3.49% arginine had significant high WG and SGR(P0.05);but no significant difference for the body composition of crab was found.Based on the growth response and quadratic model regression analysis of the relationship of WG with dietary Lys,Met or Arg levels,the Lys,Met and Arg requirements of juvenile Chinese mitten crab were estimated to be 2.34%,1.12% and 3.62% respectively.

A study was conducted to investigate the effects of dietary phosphorus on juvenile red claw crayfish Cherax quadricarinatus.Seven isonitrogenous and isoenergetic diets with different phosphorus levels(0.72,0.85,1.00,1.16,1.32,1.47and 1.74%)were prepared using fish meal and soybean meal as the main protein sources.Juvenile red claw crayfish with an initial mean weight 2.25±0.12 g were fed to satiation with one of the seven diets for 8 weeks.The results showed that the influences of different dietary phosphorus on the weight gain,specific growth rate,survival rate and feed conversion ratio were significant(P0.05).The weight gain and specific growth rate increased with dietary phosphorus increasing,from 0.72% to 1.47%,the specific growth rate reached the maximal value at dietary phosphorus 1.34%.Survival rate increased with the dietary phosphorus increasing from 0.72% to 1.00% and no differences were observed with the dietary phosphorus increasing,the survival rates were all 100%.Meanwhile,the whole body and carapace phosphorus level increased,and the crude lipid level in the whole body and hepatopancreas decreased with the increase of dietary total phosphorus.The activity of tissue protease and plasma alkaline phosphatase could be enhanced at the suitable dietary phosphorus levels while hepatopancreas alkaline phosphatase activity was negatively related to dietary total phosphorus.Based upon the present study,a diet containing 1.32%-1.47% total phosphorus might be considered as the optimum levels for growth,survival and tissue mineralization.

Six test diets with protein levels varying from 250 to 500 g kg−1 were fed to six triplicate groups of summerling (initial weight: 1.56 g) and seven test diets with protein levels varying from 200 to 500 g kg−1 were fed to seven triplicate groups of winterling (initial weight: 9.49 g) for 8 weeks. Weight gain (WG) and feed efficiency (FE) of summerling significantly increased with increasing dietary protein levels from 250 to 350 g kg−1 and slightly declined, but without statistical significance at a dietary protein level of 400 g kg−1, then further significantly decreased with increasing protein levels to 450 and 500 g kg−1; WG of winterling increased significantly with increasing dietary protein levels from 200 to 300 g kg−1 (P < 0.05), and above this level, WG had a tendency to decrease with increasing dietary protein levels. Winterling fed diets with 300 and 400 g kg−1 of dietary protein had significantly higher FE than those fed other diets. WG data analysis by quadratic regressions showed that the optimum dietary protein levels required for the maximum growth of summerling and winterling were 374 and 355 g kg−1 of dry diet respectively. Protein efficiency ratio of both summerling and winterling negatively correlated with levels of dietary protein. The whole body moisture, protein, lipid and ash of summerling after being fed various test diets for 8 weeks were significantly different among treatments (P < 0.05). The whole body moisture and fat of winterling were also significantly affected by dietary protein levels (P < 0.05), while the whole body protein and ash of winterling were not (P > 0.05).

A 56-day feeding trail was conducted to observe the influence of varying levels of phytase on growth performance,body composition and utilization of phosphorus in oriental river prawn Macrobrachium nipponense.The prawns(average wt.0.199±0.89 g) were stocked triplicately in a recirculating tank system(0.75 m×0.45 m×0.3 m) indoor.Seven trial diets were formulated for the experimental treatments.Exprimental group 1-6 were added different levels(0,250,500,1 000,1 500,2 000 U/kg) of phytase in the basic diet,respectively.The test group 7 was added 1.2% of the CaH2PO4,but without supplementation of phytase.The experimental shrimps were fed to satiation(twice/day) under the water temperature of 27±2.0 ℃.The results showed that there were no significant difference in survival rates among the different treatments with different phytase levels.WGR and SGR of the prawns fed the diets containing 500 U/kg phytase was significantly higher (P0.05) than those fed the diets containing 0 U/kg phytase;but no significant difference was found in whole body moisture,crude protein,crude lipid,ash and gross phosphorus levels among all treatments;compared with the control group,the activity of protease and lipase of hepatopancreas was increased significantly(P0.05).

The investigation on species and biomass of zoobenthos was conducted in southern Taihu Lake with 9 sampling stations from May to October in 2008. A total of 21 species of zoobenthos were recorded,which belonged to 11 families. And the dominant species were Corbicula fluminea and Limnodrilus hoffmeisteri. The density and biomass of zoobenthos were 769 ind./m2 and 248.783 g/m2,respectively which decreased significantly at peak of cyanobacterial bloom.

用添加或不添加1000(IU/kg饲料)酸性植酸酶、4种磷酸二氢钙用量(0、5、10和15g/kg饲料)设计配方,制成8种试验饲料,开展为期8周的青鱼饲养试验.结果表明,青鱼摄食无植酸酶、加15 g/kg磷酸二氢钙的饲料(饲料4)和有植酸酶且磷酸二氢钙用量为10～15 g/kg的两种饲料(饲料7、8)后,鱼体增重和鳞片磷含量显著高于其它组,而饲料系数则较低,鱼体水分升高,脂肪降低.饲料中磷酸二氢钙用量为0～10g/kg时,添加植酸酶能使饲料磷在鱼体内的积累率显著高于其它试验组(P<0.05).试验鱼摄食无植酸酶和磷酸二氢钙的试验饲料(饲料1)后,其肌肉和鳞片的灰分含量、鳞片磷含量显著低于其它各组(P<0.05).青鱼摄食无植酸酶但磷酸二氢钙用量为0或5g/kg的试验饲料(饲料1和饲料2)和摄食有植酸酶但不加磷酸二氢钙种试验饲料(饲料5)后,全鱼磷含量显著低于摄食有植酸酶且饲料中磷酸二氢钙用量为5～15 g/kg的3个试验组(P<0.05).

青蟹(Syclla sp.)在我国北起江苏连云港,南至海南岛均有分布,传统上我国_直称其为锯缘青蟹(s.serrata),最新的研究表明,青蟹属分为4个种:锯缘青蟹、紫螯青蟹(S.tranquebarica)、拟穴青蟹(S.paramaosain)、榄绿青蟹(S.olivacea).而我国东海地区分布的常见种为拟穴青蟹.

In order to investigate hydrophyte role on the purification of pond effluent which was eutrophic,three hydrophytes(Phragmites communis Trin.,Ceratophyllum demersum and Trapa quadrispinosa Roxb.) were grown in treated water and as a none-plant to compare effectiveness of nutrient removal.It can be concluded that all the hydrophytes had a good performance on removal nutrients from treated water rather than without hydrophyte.After growing the three hydrophytes 50 days,the total nitrogen(TN) was removed by P.communis Trin.(80.8%)T.quadrispinosa Roxb.(62.6%)C.demersum(34.4%).The total phosphorus(TP) was removed by P.communis Trin.(73.2%)C.demersum(27.1%)T.quadrispinosa Roxb.(17.2%).P.communis Trin.and C.demersum grew better in pond effluent than that of T.quadrispinosa Roxb.during experiment period.The average livability of P.communis Trin.and C.demersum reached up to 85% and 60%,respectively.However,T.quadrispinosa Roxb.only kept under 45%.For the three hydrophytes growing under the same condition,P.communis Trin.was the most effective hydrophyte for TN and TP removal,T.quadrispinosa Roxb.was next for TN removal.However,C.demersum was better than T.quadrispinosa Roxb.for TP removal.

鹄沼枝额虫是一种淡水小型甲壳动物,主要以细菌、有机碎屑和单胞藻等为食.用豆腐、虾片、米糠、大豆、面粉、小球藻6种饵料培养鹄沼枝额虫幼体,经11d培育,结果显示,不同饵料对鹄沼枝额虫生长、成活率有显著影响.方差分析表明,虾片组的鹄沼枝额虫体长增长显著优于其他5种饵料组(P<0.05);小球藻组的鹄沼枝额虫成活率显著高于米糠、豆腐和面粉组(P<0.05),但与虾片和大豆组没有显著性差异(P>0.05).虾片培养的鹄沼枝额虫较其他5种饵料提早1-2d产卵,且初次产卵量和卵径均为最大.用虾片、大豆、米糠、虾片+米糠、大豆+米糠5种饵料投喂性腺刚开始发育的鹄沼枝额虫,经27d培育,结果表明,不同饵料组间的鹄沼枝额虫生殖力差异显著.虾片+米糠培育的鹄沼枝额虫生殖总量显著高于米糠和大豆(P<0.05),而与虾片和大豆+米糠组没有显著性差异(P>0.05).因此,虾片和虾片+米糠是培养鹄沼枝额虫的优质饵料,对其生长和种群增殖有明显的促进作用.

A feeding experiment was conducted in water flow-through tank system to evaluate the effects of dietary fish meal(FM) replacement by mixture of soybean meal(SBM) and rapeseed meal(RSM) on the growth performance and body composition of fingerling black carp(Mylopharyngodon piceus).A typical diet with 38% crude protein level(fishmeal protein: plant protein =1:1) was used as the control(Diet A).The other experimental diets(Diets B-E) in which 25%,50%,75% and 100% of fishmeal protein contained in the control diet were replaced by mixture of soybean meal and rapeseed meal(soybean meal: rapeseed meal=1:1) respectively.Five triplicate groups of fish were fed the isocaloric(13.3 kJ.g-1 feed energy) and isonitrogenous(38% crude protein) trial diets three times per day at 3%-5% of fish body weight for 8 weeks.30 fish with an initial average weight of(1.32 ± 0.09) g was stocked in each tank.The results showed that there were no significant difference for weight gain(WG),specific growth rate(SGR) and feed conversion ratio(FCR) among fish fed diet B,diet C and diet A(P0.05).The protein efficiency rate(PER) in fish fed the diet A and diet B was significantly higher than that of diet E(P0.05),but no significant difference was found between diet A and diet B (P0.05).Body composition analysis showed that whole body moisture content increased significantly(P0.05) but crude lipid content decreased significantly with the increasing of dietary plant protein levels(P0.05).No significant difference for the essential amino acid(EAA) of the muscle was found among different dietary plant protein levels(P0.05).There were no significant difference for the hepatosomatic index,viscerasomatic ratio and condition factor among fish fed the diets with dietary replacement levels(P0.05).The results indicated that 25%-50% FM protein could be replaced by mixture of SBM and RSM without significantly reducing growth of fingerling black carp.