Compensatory growth in the gibel carp following feed deprivation: temporal patterns in growth, nutrient deposition, feed intake and body composition

To investigate the nature of compenstory growth in fish, an 8 week study at 28 degreesC was performed on juvenile gibel carp Carassius auratus gibelio weighing 6.6 g. Fish were starved for 0 (control), 1 (Sl)or 2 (S2) weeks and then re-fed to satiation For 5 weeks. Weekly changes in weight gain, feed intake and body composition were monitored during re-feeding. No significant difference was found in final body weight between the three groups, indicating complete compensation in the deprived fish, The deprived groups caught up in body weight with that of the control after 2 weeks of re-feeding. Body fat:lean body mass ratio was restored to the control level within 1 week of re-feeding. In the re-feeding period, weekly gains in body weight, protein. lipid, ash and energy in the S1 group were significantly higher than in the controls for 1 week. For the S2 group, weekly gains in body weight. lipid. ash and energy were higher than in the controls for 2 weeks, and gain in protein was higher than in the controls for 3 weeks, though gain in body energy became elevated again during the last 2 weeks of the experiment. Feed intake remained higher than the control level for 3 weeks in the S1 group and 3 weeks in the SZ group. Growth efficiency was not significantly different among the three groups in any of the weeks during re-feeding. Compensatory responses in growth and especially feed intake tended to last longer than the recovery of body composition. (C) 2001 The Fisheries Society of the British Isles.

Whole-body amino acid pattern of F-4 human growth hormone gene-transgenic red common carp (Cyprinus carpio) fed diets with different protein levels

F-4 generation of human growth hormone (hGH) gene-transgenic red common carp, and the non-transgenic controls were fed for 8 weeks on purified diets with 20%, 30% or 40% protein. Analysis of whole-body amino acids showed that the proportions of lysine, leucine, phenylalanine, valine and alanine, as percentages of body protein, increased significantly, while those of arginine, glutamic acid and tyrosine decreased, with increases in dietary protein level in at least one strain of fish. Proportions of the other amino acids were unaffected by the diets. The proportions of lysine and arginine were significantly higher, while those of leucine and alanine were lower in the transgenics than in the controls in at least one diet group. Proportions of the other amino acids were unaffected by strain. The results suggest that the whole-body amino acid profile of transgenic carp, when expressed as proportions of body protein, was in general, similar to that of the non-transgenic controls. (C) 2000 Elsevier Science B.V. All rights reserved.

Effect of body size on growth and energy budget of Nile tilapia, Oreochromis niloticus

A growth trial was conducted at 30 degrees C to investigate the effect of body size on growth and energy budget of Nile tilapia. The average initial body weights of the four size groups tested were 9.3, 34.1, 80.3 and 172.4 g, respectively. Fish were fed to satiation twice a day with a diet containing 35.6% crude protein. Food consumption (C-max: kJ/day) increased with body size (W: g) according to the relationship: Ln C-max = 1.45 + 0.42 LnW. The final body contents of dry matter, crude protein and ash per unit body weight increased with increasing body size while contents of fat and energy were independent of body size. Specific growth rates of wet weight, dry weight, protein and energy decreased as the fish increased in size. Feed efficiencies in wet weigh, dry weight and crude protein decreased with increasing body size, while that of energy remained unchanged. The proportions of energy intake allocated to the various components (faecal energy, excretory energy, heat production and recovered energy) of the energy budget were not significantly affected by body size, and the average budget was: 100IE-18.5(+/- 1.33)FE + 5.9 (+/- 3.09)(ZE + UE) + 49.3(+/- 3.77)HE + 26.3(+/- 6.23)RE, where IE, FE, (ZE + UE), HE and RE represent gross energy intake, faecal energy, excretory (non-faecal) energy loss, heat production and recovered energy (growth), respectively. It is suggested that the decrease in growth rate in larger fish is mainly due to the decrease in relative food intake. (C) 1997 Elsevier Science B.V.

Effect of ration and body size on the energy budget of juvenile white sturgeon

Growth and energy budget were measured for three sizes(2.4, 11.1 and 22.5 g) of juvenile white sturgeon Acipenser transmontanus held at 18.5 degrees C and fed tubificid worms at different levels ranging from starvation to ad libitum. For each size-class, specific growth rate increased linearly with increasing ration, and conversion efficiency was highest at the maximum ration. Growth rate decreased with increasing fish size at the maximum ration, but increased with size al each restricted ration. Conversion efficiency increased with increasing ration for each size-class and was usually highest at the maximum ration. Faecal production accounted for 3.2-5.2% of food energy. The proportion of food energy lost in nitrogenous excretion decreased with increasing ration. With increases in ration, the allocation of metabolizable energy to metabolism decreased, while that to growth increased. Fish size had no significant effect on the allocation of metabolizable energy to metabolism or growth. Al the maximum ration, on average 64.9% of metabolizable energy was spent on metabolism, and 35.1% on growth. (C) 1996 The Fisheries Society of the British Isles

Silicon nanowires grown on a pre-annealed Si substrate

Polycrystalline Si nanowires (poly SiNWS) were successfully synthesized by plasma-enhanced chemical vapor deposition (PECVD) at 440degreesC using silane as the Si source and Au as the catalyst. The diameters of Si nanowires range from 15 to 100nm. The growth process indicates that to fabricate SiNWS by PECVD, pre-annealing at high temperature is necessary. A few interesting nanowires with Au nanoclusters uniformly distributed in the body of the wire were also produced by this technique. (C) 2002 Elsevier Science B.V. All rights reserved.

A simulation model of body contact structure in PD SOI analogue circuit

As a solution of accurate simulation of the body effect in PD SOI analogue circuit, a simulation model of distributed body contact resistance and parasitical capacitance is presented. Based on this model, we have designed and simulated a sense amplifier that applied to V a 0.8um PD SOI 64K SRAM.

Polymorphous silicon nanowires synthesized by plasma-enhanced chemical vapor deposition

Polymorphous Si nanowires (SiNWS) have been successfully synthesized on Si wafer by plasma enhanced chemical vapor deposition (PECVD) at 440degreesC,using silane as the Si source and Au as the catalyst. To grow the polymorphous SiNWS preannealing the Si substrate with Au film at 1100 degreesC is needed. The diameters of Si nanowires range from 15 to 100 urn. The structure morphology and chemical composition of the SiNWS have been characterized by high resolution x-ray diffraction, scanning electron microscopy, transmission electron microscopy, as well as energy dispersive x-ray spectroscopy. A few interesting nanowires with Au nanoclusters uniformly distributed in the body of the wire were also produced by this technique.

Hydroelastic dynamic characteristics of a slender axis-symmetric body

The slender axis-symmetric submarine body moving in the vertical plane is the object of our investigation. A coupling model is developed where displacements of a solid body as a Euler beam (consisting of rigid motions and elastic deformations) and fluid pressures are employed as basic independent variables, including the interaction between hydrodynamic forces and structure dynamic forces. Firstly the hydrodynamic forces, depending on and conversely influencing body motions, are taken into account as the governing equations. The expressions of fluid pressure are derived based on the potential theory. The characteristics of fluid pressure, including its components, distribution and effect on structure dynamics, are analyzed. Then the coupling model is solved numerically by means of a finite element method (FEM). This avoids the complicacy, combining CFD (fluid) and FEM (structure), of direct numerical simulation, and allows the body with a non-strict ideal shape so as to be more suitable for practical engineering. An illustrative example is given in which the hydroelastic dynamic characteristics, natural frequencies and modes of a submarine body are analyzed and compared with experimental results. Satisfactory agreement is observed and the model presented in this paper is shown to be valid.

在盐胁迫下外源维生素浸种对小麦发芽及幼苗生长的影响

维生素(Vitamin)又称维他命，为“万年青”产品，是维持人体生命健康必需的一类低分子有机化合物质。维生素对人体健康的作用人们研究很多, 维生素可以增强人体对感染的抵抗力，降低出生缺陷及降低癌症和心脏病发病率等，一旦缺乏，肌体代谢就会失去平衡，免疫力下降，各种疾病，病毒就会趁虚而入；而维生素对作物影响的研究却很少。目前为止，尚无对用维生素浸种的方法来研究外源维生素是否对小麦种子萌发及幼苗生长起调节作用的报道，且对其在小麦抗逆性方面影响的研究甚少，对盐的胁迫抗性研究尚未有人报道。小麦（Triticum aestivum L.）属于拒盐的淡土性作物。盐害不利于小麦生长，严重影响小麦的产量和品质。本研究采用4 种不同维生素VB1、VC、VB6、VPP，分别对供试小麦品种川育12（红皮）、川育16（白皮）小麦浸种后，在一般自然条件下和逆境（盐胁迫条件）下，进行试验。探讨在正常情况下与在不同盐浓度条件下，各维生素及盐浓度对小麦发芽及幼苗生长的影响，并且比较两种不同皮色的小麦在相同盐胁迫条件下的差异表现，同时研究维生素处理的特异性，且哪种维生素对盐害缓解作用最佳。研究结果表明：在无盐胁迫（自然）条件下，对用4 种不同维生素VB1、VC、VB6、VPP 浸种小麦川育12、川育16 后的种子萌发及幼苗生长（幼苗的根长、根重、苗高、苗鲜重）的研究结果表明：4 种外源维生素浸种均对小麦发芽有调节作用，都能提高其最终发芽率。但是提高幅度有所差异。用VB6 浸种后的小麦提高幅度最多，VC 次之，VPP 提高幅度最小。同时，4 种外源维生素浸种对小麦种子的出芽速度及芽后长势也有一定的影响。VB6、VC 处理的小麦种子出芽速度最快，萌发后长势最好；VB1 出芽速度相对较慢，VPP 最慢,但都大于对照；VB1 处理长势略高于对照，VPP 处理的小麦长势则低于对照。从整体来看，VB6、VC处理促进效应明显， VB1 次之，而VPP 在某些方面无效甚至产生负效应。此外，相同的维生素处理对不同的品种的种子萌发、生长效果也存在差异，各种维生素作用于川育12 的效应均强于对川育16。进一步对幼苗根系TTC 还原力及幼苗叶片中硝酸还原酶活性进行测定、分析。研究发现：并非所有种类的维生素对幼苗根系TTC 还原力及幼苗叶片中硝酸还原酶活性的提高都有帮助。幼苗根系TTC 还原力在不同维生素处理下存在显著差异，而与小麦品种关系甚微。经VB6、VC 处理后，根系TTC 还原力测定值均显著高于对照，VB1 不明显，VPP 则略低于对照。VB6、VC 处理的幼苗叶片中硝酸还原酶的含量大于对照，VB1 与对照相差无几，而VPP 处理的川育12 幼苗叶片中的硝酸还原酶活性比对照CK 略高，而在川育16 中则略比对照CK 有所下降，呈现出抑制效应。综上结果表明：VB6、VC 具有促进种子发芽，幼苗生长及根系生长的作用，是较好的促生长剂；VPP 具有抑制作用，是较好的抑制剂，可进一步研究、开发利用。在盐胁迫条件下，对用4 种不同维生素VB1、VC、VB6、VPP 浸种川育12、川育16 后的种子萌发及幼苗生长（幼苗的根长、根重、苗高、苗鲜重）的研究结果表明：在不同盐浓度胁迫条件下， 各处理的种子萌发及幼苗生长均受到不同程度的抑制。随着盐浓度的增加, 发芽率、发芽指数和活力指数成下降趋势；幼苗的根长、根重、苗高、苗鲜重不断降低。4 种维生素处理间也表现出较大差异。VB6、VC 在每个处理中均保持对盐害的缓解作用，VB6 较VC 更易于促进发芽及幼苗生长。最终发芽率高，根系多、长、重，苗高高、重。而VB1、VPP 则表现出抑制作用。在高盐浓度150mM 时，4 种维生素浸种后的种子，其最终发芽率均不能达到40％，但VB6、VC 处理最终发芽率、苗重、根重均高于对照，VPP 最终发芽率、苗重、根重均低于对照。进一步对幼苗根系TTC 还原力及幼苗叶片中脯氨酸含量进行测定、分析。研究发现：不同盐浓度，不同维生素处理、不同品种间存在差异。随着盐浓度的增加（75mM，100mM，150mM），幼苗根系TTC 还原力活性成下降趋势，幼苗叶片中脯氨酸的积累量成上升趋势。VB6 处理脯氨酸含量增加最为明显，VC 次之，VPP 与对照接近，其变化幅度最小。经VB6、VC 处理后的幼苗根系还原强度，在不同盐浓度下，测定值均显著高于对照，VB1 不明显，VPP 则低于对照，产生负效应。此外，品种间表现不尽相同，相同的维生素处理，相同的盐浓度对不同的品种的种子萌发、生长效果也存在差异， 4 种维生素对川育16 的作用均强于川育12，但其影响趋势是一致的。说明VB6、VC 具有耐（抗）盐性，可以促进种子发芽和幼苗生长，是较好的耐（抗）盐拌种剂。 Vitamin is one kind of necessary low molecular compound for humans tosustain health and life. Lots of Studies have been done on the effectc of the vitaminsfor people. Vitamin can help people improve the body's natural resistance to disease,Drop the rate of birth defects、cacers and the incidence of the heart diseases. Ifpeople have less of them, the metabolism of the organism may throw off balance,immunity may drop off, and catch disease; Though the effects for Vitamin to thecrops are limited. up to now, there’s no one use soking seeds of wheats with vitaminsas a method, to study on how the effects will happen on the wheat seed germinationand seedling growth, and there are only few reserches on antireversion force forwheats ,none for the antireversion force in Sault stress condition.Wheat（Triticum aestivum L.）is sensitive to the salt, so the salt damage will doharm to wheat’s growth, it will have an unfavorable impact on the output and thequality of wheat.On this reaserch, we Soaking CHY12(red)、CHY16 (white) wheat seeds withVitamin C, B1, PP, B6 (50mg/L) as a pretreatment first. Then under two condition: one is in the normal environment the other is in different Salinity, we begin ourexperiments. Then disscuss on if the vitamin and salinity affect the wheat seedgermination and seedling growth, and what is the different between the two of them,the result shows that:Under the normal condition, after soaking seeds with VB1、VC、VB6、Vpp，we study on the their seed germination and the seeding growth(the root length andweights, The seedling heights and weights), it shows that all of those four kinds ofvitamin can adjust the seed germination, but different in The growth rate. VB6 isbest for increase, VC comes second,VPP is the worst. Meanwhile, those four vitaminalso have effect on the speed of the sprouting of the wheat. VB6、Vc can faster theseed germination most, and the seedlings are all doing well; VB1 do little effects onthe budding, Vpp is the worst, but all treatments are better than CK; but in Vi, VB1some what above the CK, while VPP lower than that. On the whole, the acceleratingeffect of VB6、VC are obvious, VB1 takes second place, but VPP in some aspects arenoneffective even have negative effect. Furthermore, different kind of seeds with thesame vitamin may different in seed germination and seedling growth, four vitaminson CHY16 is better than CHY12.More studies on TTC reductive capacity of roots and the activity of nitratereductase in the leaves, the reasult shows not all the vitamin can help the seedlings toimprove the TTC reductive capacity and the activity of nitrate reductase. TTCreductive capacity in different treatments shows significant differences,but notcorrelate to the variety of the wheat. The TTC reductive capacity of VB6、Vctreatments are all higher than CK, VB1 is nearly the same as CK, VPP is a littlelower than CK. Through the study of acivity of nitrate reductase, it shows that,VB6、VC are higher than CK ,VB1 is nearly the same as CK also, VPP is a little higher inthe CK of CHY12 but lower in CHY16. Through all the results above: VB6、Vc helpthe wheat seed germination, seedling growth and the growth of roots, is theperfectable factor of stimulating the growth; Vpp is a inhibition, that’ll be furtherreserch,and well develop and utilize in the future.Under the different Salinity condition, after soaking seeds with VB1、VC、VB6、Vpp，we study on the their seed germination and the seeding growth(the root lengthand weights, The seedling heights and weights), it shows that: under differentsalinity, the seed germination and the seedling growth of any treatment are inhibited.With the increase of the concentration, the germination rate, Vi、Gi all had fallen; theroot length and weight, the seedling heights and weights steadily sank down. There are also have pronounced difference between all treatments with four differentvitamins.VB6、VC in all treatments are alleviative the salt damage, VB6 is easier tocause to put forth buds than VC, and it’s quantitative value is the highest in theultimate germination rate, in root and seedlings’ hight and weight. Though the VPP、VB1 are seems to inhibite its growth. Under the high concentration150mM Nacl, theultimate germination rate in all treatments are below the 40%, but VB6、VC’squantitative values in any experiments are higher than CK,while VPP lower thanCK.Then we study on the TTC reductive capacity of roots and the content of Polinein leaves, the result shows that between the different salinity, different vitamintreatments, different varieties of the wheat have discrepancy.along with theincreasing concentraion of the salinity（75mM，100mM，150mM），TTC reductivecapacity of roots decreases, the accumulation of the content of Poline in leaves havean upward trend. The increase of VB6’s treatment are obviously, VC comessecond,VPP is nearly come up with CK, changes a little. In TTC reductive capacity of roots’s reserch, VB6、VC are higher than CK at any time,VB1 is not palpable,VPP is lower than CK, makes negative affect on wheat. In addition, varieties of thewheats are remain different, no matter it shows promoting or inhibiting, all fourvitamins have moreobvious effects on CHY16 than CHY12, but the tendency of theeffection are the same. It is say that VB6、VC can help wheat to standwith the saultwell, and promot in growth，they are the better reagent to mix with the seed.