Phenotypic plasticity in gut length in the planktivorous filter-feeding silver carp (Hypophthalmichthys molitrix)

Phenotypic plasticity widely exists in the external morphology of animals as well as the internal traits of organs. In the present study, we studied the gut length plasticity of planktivorous filter-feeding silver carp under different food resources in large-net cage experiments in Meiliang Bay of Lake Taihu in 2004 and 2005. There was a significant difference in stocking density between these 2 years. Under a low stocking density and abundant food resources, silver carp increased their energy intake by feeding on more zooplankton. Meanwhile, silver carp adjusted their gut length to match the digestive requirements of food when exposed to different food resources. In the main growth seasons (from April to October), silver carp significantly increased their relative gut length when feeding on more phytoplankton in 2005 (p < 0.01, 9.23 +/- 1.80 in 2004 and 10.77 +/- 2.05 in 2005, respectively). There was a nearly significant negative correlation between zooplankton proportion in the diet and the relative gut length when silver carp were stocked in a high density (p = 0.112). It appears that silver carp might have evolved plasticity to change their gut length rapidly to facilitate efficient utilization of food resources. Such resource polymorphisms in the gut may be a good indication of temporal adaptation to resource conditions. Our work provided field evidence for understanding the functional basis of resource polymorphisms and the evolution of phenotypic plasticity in planktivorous filter-feeding fish.

模拟酸雨对马尾松菌根影响研究

本实验表明：外生菌根真菌彩色豆马勃、劣味乳菇、丝膜菌对PH的适应范围较广，最适生长BH呈酸性。模拟酸雨对马尾松幼苗菌根的外部形态和内部结构有明显影响。在温室栽培中，模拟酸雨（PH2.0）显著抑制菌根侵染率，在田间实验中，对菌根侵染率有一定的影响。菌根PH和土壤PH值随模拟酸雨PH下降而逐渐降低，接种菌根菌可略提高菌根PH和土壤PH值。菌根真菌过氧化氢酶对培养基中PH的变化不敏感，模拟酸雨对菌根过氧化氢酶活性影响也不明显。但沙培中，模拟酸雨（PH2.0）显著抑制菌根过氧化氢酶活性。模拟酸雨（PH2.0）显著刺激菌根过氧化物酶活性，接种菌根菌可以降低菌根过氧化物酶活性。不同PH的培养基对菌体硝酸还原酶活性有明显影响，而且菌体生长速度与硝酸还原酶活性呈正相关。模拟酸雨（PH2.0）显著抑制菌根硝酸还原酶活性，而接种菌根菌明显提高根系硝酸还原酶活性。菌体酸性磷酸酶活性对培养基中PH变化不敏感，同样菌根酸性磷酸酶活性对模拟酸雨的影响也不明显，但是接种菌根菌可明显提高根系酸性磷酸酶活性。模拟酸雨对马尾松幼苗茎的高生长影响不显著。但是对幼苗茎、根系的干重和侧根总长度有显著抑制作用。轻度酸雨（PH4.5-3.0）对马尾松幼苗生长有促进作用，接种菌可提高幼苗生长。从菌根形态结构和生理活性上看，接种菌根菌可减轻模拟酸雨对马尾松幼苗根系的危害，增强对模拟酸雨的抗性。4dThe result of experiment showed that ectomycorrhizal fungi Pisolithus tinctorins. Lactarius insulsus. Cortinarius russus can be growth in broad PH rang in pure culture, the optimum growth PH is acidity. The external morphology and internal structure of ectomycorrhiza of P. massoniana are affected with simulated acid rain. In greenhouse, simulated acid rain (PH2.0) treatment caused significant decrease in the percent infection, but it's not marked in field. The PH of mycorrhizal and soil are reduced with reducing rainfall PH. These PH are slight higher for inoculation with ectomycorrhizal fungi. Catalase activity of ectomycorrhizal fungus is not sensitive to medium with different PH. Mycorrhiza catalase activiyt is not affected significantly with simulated acid rain, but it's inhibited significantly with simulated acid rain (PH2.0) in the sand culture. Peroxidase atcivity of mycorrhiza is enhanced significantly with simulated acid rain (PH2.0), but it's universally lower for inoculation with ectomycorrhizal fungus. Ectomycorrhizal fungus nitrate reductase activity is affected significantly to medium with differdnt PH, the rates of these fungi growth and nitrate reductase activity is significant correlation. Nitrate reductase activity of mycorrhiza is inhibited significantly with simulated acid rain (PH 2.0), but it's increased significantly for inocnlation with mycorrhizal fungi. Ectomycorrhizal fungas acid phosphatase activity is not affected to medium with different PH, Mycorrhiza acid phosphatase activity is not affected with simulated acid rain too, the acid phosphatase activity of roots inoculated with mycorrhizal fungas is increased significantly. The highest acidity level simulated rain reduced signhficantly root system biomass and the dry weight of stem. Iower acidity level simulated rain can stimulated the growth of P. massoniana, the growth of seedling inocnlated with mycorrhizal fungus can be increased.

Solvent-induced Morphology of the Binary Mixture of Diblock Copolymer in Thin Film: The Block Length and Composition Dependence of Morphology

A series of binary SB blend samples with various overall volume fraction of PS (Phi(PS)) and different discrete distribution of the block length (denoted as d(PS) or d(PB)) were prepared by mixing various asymmetric poly(styrene)-block-poly(butadiene) (SB) block copolymers with a symmetric SB block copolymer. The influences of the external solvent field, composition, and the block length distribution on the morphologies of the blends in the thin films were investigated by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The experimental results revealed that after solvent annealing, the interface of the blend thin films depended mainly on the cooperative effects of the annealing solvent and the inherently interfacial curvature of the blends. Upon exposure to the saturated vapor of cyclohexane, which has preferential affinity for the PB block, a "threshold" of Phi(PS) (approximate 0.635-0.707) was found. Below such threshold, the influence of the annealing solvent played an important role on the interfacial curvature of the blend thin film.

Heat-Transfer Study of External Superheater of CFB Incinerator

The heat transfer coefficients for horizontally immersed tubes have been studied in model internally circulating fluidized bed (ICFB) and pilot ICFB incinerators. The characteristics in the ICFB were found to be significantly different from those in a bubbling bed. In ICFB, there is a flowing zone with high velocity, a heat exchange zone, and a moving zone with low velocity. The controllable heat transfer coefficients in ICFB strongly depend on the fluidized velocity in the flowing zone, and also the flow condition in the moving zone. The heat exchange process and suitable bed temperature can be well controlled according to this feature. Based on the results of experiments, a formulation for heat transfer coefficient has been developed. These results were applied to an external superheater of a CFB incinerator with a 450 degreesC steam outlet in a waste-to-energy pilot cogeneration plant of 12 MW in Jiaxing City, China.

Numerical Simulation and Experimental Investigation about Internal and External Flows

In this paper, TASCflow3D is used to solve inner and outer 3D viscous incompressible turbulent flow (R-e = 5.6 X 10(6)) around axisymmetric body with duct. The governing equation is a RANS equation with standard k-epsilon turbulence model. The discrete method used is a finite volume method based on the finite element approach. In this method, the description of geometry is very flexible and at the same time important conservative properties are retained. The multi-block and algebraic multi-grid techniques are used for the convergence acceleration. Agreement between experimental results and calculation is good. It indicates that this novel approach can be used to simulate complex flow such as the interaction between rotor and stator or propulsion systems containing tip clearance and cavitation.

Deformation Morphology Underneath the Vickers Indent in Bulk Metallic Glasses

Plastic deformation behaviour of Zr52.5Al10Ni10Cu15Be12.5 and Mg65Cu25Gd10 bulk metallic glasses (BMGs) is studied by using the depth-sensing nanoindentation and microindentation. The subsurface plastic deformation zone of the BMGs is investigated using the bonded interface technique. Both the BMGs exhibit the serrated flow depending on the loading rate in the loading process of indentation. Slow indentation rates promote more conspicuous serrations, and rapid indentations suppress the serrated flow. Mg-based BMG shows a much higher critical loading rate for the disappearance of the serration than that in Zr-based BMG. The significant difference in the shear band pattern in the subsurface plastic deformation zone is responsible for the different deformation behaviour between the two BMGs. Increase of the loading rate can lead to the increase of the density of shear bands. However, there is no distinct change in the character of shear bands at the loading rate of as high as 1000 nm/s.

From Hexagonally Arrayed Nanorods To Ordered Porous Film Through Controlling The Morphology Of Zno Crystals

The macrostructure can be changed by changing the morphology of its units. In this article, we use a colloidal template route, combined with hydrothermal growth method, to get the hexagonally arrayed ZnO nanorods on the polycrystalline ZnO substrate. More significantly, through controlling the morphology of ZnO crystals by adding structure-directing agent in the precursor solution, the highly ordered porous ZnO films were obtained instead of ZnO nanorods. This templated solvent-thermal method has great potential in micro/nano-fabrication. (C) 2008 Elsevier B.V. All rights reserved.

Numerical Simulation and Experimental Investigation about Internal and External Flows

In this paper, TASCflow3D is used to solve inner and outer 3D viscous incompressible turbulent flow (R-e = 5.6 X 10(6)) around axisymmetric body with duct. The governing equation is a RANS equation with standard k-epsilon turbulence model. The discrete method used is a finite volume method based on the finite element approach. In this method, the description of geometry is very flexible and at the same time important conservative properties are retained. The multi-block and algebraic multi-grid techniques are used for the convergence acceleration. Agreement between experimental results and calculation is good. It indicates that this novel approach can be used to simulate complex flow such as the interaction between rotor and stator or propulsion systems containing tip clearance and cavitation.

Exact solutions to collisionless external gas flows

This paper presents exact density, velocity and temperature solutions for two problems of collisionless gas flows around a flat plate or a spherical object. At any point off the object, the local velocity distribution function consists of two pieces of Maxwellian distributions: one for the free stream which is characterized by free stream density, temperature and average velocity, n0, T0, U0; and the other is for the wall and it is characterized by density at wall and wall temperature, nw,Tw. Directly integrating the distribution functions leads to complex but exact flowfield solutions. To validate these solutions, we perform numerical simulations with the direct simulation Monte Carlo (DSMC) method. In general, the analytical and numerical results are virtually identical. The evaluation of these analytical solutions only requires less than one minute while the DSMC simulations require several days.

Long lifetime plasma channel in air generated by multiple femtosecond laser pulses and an external electrical field

The lifetime of a plasma channel produced by self-guiding intense femtosecond laser pulses in air is largely prolonged by adding a high voltage electrical field in the plasma and by introducing a series of femtosecond laser pulses. An optimal lifetime value is realized through adjusting the delay among these laser pulses. The lifetime of a plasma channel is greatly enhanced to 350 ns by using four sequential intense 100fs( FWHM) laser pulses with an external electrical field of about 350kV/m, which proves the feasibility of prolonging the lifetime of plasma by adding an external electrical field and employing multiple laser pulses. (c) 2006 Optical Society of America.

Optical intrinsically fuzzy mathematical morphology for gray-scale image processing

Intrinsically fuzzy morphological erosion and dilation are extended to a total of eight operations that have been formulated in terms of a single morphological operation--biased dilation. Based on the spatial coding of a fuzzy variable, a bidirectional projection concept is proposed. Thus, fuzzy logic operations, arithmetic operations, gray-scale dilation, and erosion for the extended intrinsically fuzzy morphological operations can be included in a unified algorithm with only biased dilation and fuzzy logic operations. To execute this image algebra approach we present a cellular two-layer processing architecture that consists of a biased dilation processor and a fuzzy logic processor. (C) 1996 Optical Society of America

Logic-operated mathematical morphology and its optical implementation

A more powerful tool for binary image processing, i.e., logic-operated mathematical morphology (LOMM), is proposed. With LOMM the image and the structuring element (SE) are treated as binary logical variables, and the MULTIPLY between the image and the SE in correlation is replaced with 16 logical operations. A total of 12 LOMM operations are obtained. The optical implementation of LOMM is described. The application of LOMM and its experimental results are also presented. (C) 1999 Optical Society of America.

FUZZY SOLID SETS FOR MATHEMATICAL MORPHOLOGY AND OPTICAL IMPLEMENTATION

Fuzzy sets in the subject space are transformed to fuzzy solid sets in an increased object space on the basis of the development of the local umbra concept. Further, a counting transform is defined for reconstructing the fuzzy sets from the fuzzy solid sets, and the dilation and erosion operators in mathematical morphology are redefined in the fuzzy solid-set space. The algebraic structures of fuzzy solid sets can lead not only to fuzzy logic but also to arithmetic operations. Thus a fuzzy solid-set image algebra of two image transforms and five set operators is defined that can formulate binary and gray-scale morphological image-processing functions consisting of dilation, erosion, intersection, union, complement, addition, subtraction, and reflection in a unified form. A cellular set-logic array architecture is suggested for executing this image algebra. The optical implementation of the architecture, based on area coding of gray-scale values, is demonstrated. (C) 1995 Optical Society of America