论“三毛热”产生与消减的隐性因素

20世纪80年代至90年代大陆先后三次掀起“三毛热”,可见三毛这位颇具传奇色彩和性格魅力的台湾女作家对大陆读者的巨大影响力。“三毛热”作为文化现象,其产生与消减的因素,并不是纯粹在文本能找到解答的,在文本背后的一些隐形因素同样值得探讨。

Establishment of in Vitro Regeneration System of Triploid Chinese White Poplar

初步建立了三倍体毛白杨 (PopulustomentosaCarr.)组织培养再生系统。组织培养时 ,外植体最好选用在弱光下从休眠芽上萌发的幼芽或嫩茎 ,经HgCl2 溶液表面消毒后 ,接种到大量元素减半、含 0 .2 5mg/L吲哚乙酸和 1.0 0mg/L玉米素的MS培养基上。试管苗的生根可采用含 0 .2 5mg/L吲哚丁酸和 10mg/L维生素B1的MS培养基。试管苗茎段的分化依无性系和外源激素条件的不同而异。无性系B19的茎段较易分化 ,而无性系B30 4和B331分化较难。最适的分化培养基为大量元素减半、含 0 .0 5～ 0 .10mg/L吲哚乙酸和 1.0

Seasonal characteristics of Carex lasiocarpa biomass and nutrient accumulation in the typical wetland of Sanjiang Plain, China

Seasonal dynamics of above- and belowground biomass and nutrient characteristics （nitrogen, carbon, and phosphorus） of Carex lasiocarpa were investigated in the typical wetland of Sanjiang Plain, China from May 2007 to September 2008. The results show that the changes of aboveground biomass during the growing season are best described by the twice function curve model, whereas the changes of belowground biomass follow the exponential increase curve model. Both the organic carbon contents in the above- and belowground plant parts show significant positive linear correlations with the growing time, and the coefficients R2 are 0.983 and 0.746, respectively. The carbon accu-mulations of the above- and belowground plant parts during the growing season show the same dynamics as those of the biomass. However, the nitrogen contents and accumulation in C. lasiocarpa aboveground and belowground parts show exponential increase during the growing season. The dynamics of C. lasiocarpa phosphorus contents follows the twice function curve model, whereas the accumulation of phosphorus shows the linear increase. The ratios of C/N in different parts of C. lasiocarpa fit the negative linear relations with total nitrogen content in the growing season. Moreover, the ratios of C/P in C. lasiocarpa plant also fit the negative linear relations with total phosphorus content. The results show that nitrogen is the primary limiting nutrient for C. lasiocarpa growth as compared with carbon and phosphorus.

Description of a new Homidia species(Collembola: Entomobryidae) with labial chaetae expanded

Homidia triangulimacula sp. nov. is described from Tiantong National Forest Park, Zhejiang Province. It can be easily discriminated from other species of Homidia by triangular dark patch on dorsal central mesothorax, labial chaeta M replicated and labial basal and posterior labial chaetae expanded, 6＋6 macrochaetae on posterior abdominal segment IV, and middle S-chaeta posterior to macrochaeta m3 on abdominal segment V. A detailed morphological character comparison and a key to species with chaetae expanded on labium or posterior labium in Homidia are provided here.

Integration of Ru/C and base for reductive catalytic fractionation of triploid poplar

Lignin,which is the most recalcitrant component of lignocellulosic biomass,is also the most abundant renewable aromatic resource.Herein,reductive treatment of triploid poplar sawdust by the integration of catalytic Ru/C and a base,which afforded high yields of phenolic monomers from the lignin component and a solid carbohydrate pulp,is reported.The introduction of Cs_(2)CO_(3) led to the generation of C2 side‐chained phenols through the cleavage of C_(β)–O and C_(β)–C_(γ) bonds inβ–O–4 units in addition to C3 side‐chained phenols;the relationship between C2 and C3 was dependent on the base dosage.The reaction conditions,including base species,temperature,time,and H_(2) pressure,were optimized in terms of phenolic product distribution,delignification degree,and carbohydrate retention.The carbohydrate pulps generated from reductive catalytic fractionation in the presence of Cs_(2)CO_(3) were more amenable to enzymatic hydrolysis,indicating that this treatment of biomass constituted the fractionation of biomass components together with the breakdown of biomass recalcitrance.

Response of Regeneration Diversity of Carex Lasiocarpa Community to Different Water Levels in Sanjiang Plain,China

The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season.Regeneration diversity of Carex lasiocarpa community under different water levels was studied at two stages, recruitment and adult, in the Sanjiang Plain, Heilongjiang Province, China.The results showed that, at the two growing stages, important value of C.lasiocarpa population and species richness of the community decreased with the increasing water level, while the Simpson and Shannon-Wiener diversity indexes and Pielou evenness index increased.Under different water levels, community diversities were higher at the recruitment stage, while population important values of C.lasiocarpa were higher at the adult stage.Indexes in vegetation evaluation must be chosen prudentially for successful restoration and effective management of wetlands, and especially for wetland restoration, the optimal time should be selected according to the restoration objectives and costs.

Differential gene expression during capillary morphogenesis in a microcarrier-based three-dimensional in vitro model of angiogenesis with focus on chemokines and chemokine receptors

AIM:To globally compare the gene expression profiles during the capillary morphogenesis of human microvascular endothelial cells (HMVECs) in an in vitro angiogeness system with affymetrix oligonucleotide array. METHODS: A microcarrier-based in vitro angiogenesis system was developed, in which ECs migrated into the matrix, proliferated, and formed capillary sprouts. The sprouts elongated, branched and formed networks. The total RNA samples from the HMVECs at the selected time points (0.5, 24, and 72 h) during the capillary morphogenesis were used for microarray analyses, and the data were processed with the softwares provided by the manufacturers. The expression patterns of some genes were validated and confirmed by semi-quantitative RT-PCR. The regulated genes were grouped based on their molecular functions and expression patterns, and among them the expression of chemokines and chemokine receptors was specially examined and their functional implications were analyzed. RESULTS: A total of 1 961 genes were up- or downreg-ulated two-folds or above, and among them, 468 genes were up- or down-regulated three-folds or above. The regulated genes could be grouped into categories based on their molecular functions, and were also clustered into six groups based on their patterns of expression. As for chemokines and chemokine receptors, CXCL1/GRO-α, CXCL2/GRO-β, CXCL5/ENA-78, CXCL6/GCP2, IL-8/CXCL8, CXCL12/SDF-1, CXCL9/Mig, CXC11/ITAC, OOCL1/fractalkine, CCL2/MCP-1, CCL3, CCL5/RANTES, CCL7, CCL15, CCL21, CCL23, CCL28, and CCR1, CCR9, CXCR4 were identified. Moreover, these genes demonstrated different changing patterns during the capillary morphogenesis, which implied that they might have different roles in the sequential process. Among the chemokines identified, CCL2/MCP-1, CCL5/RANTES and CX3CL1 were specially up-regulated at the 24-h time point when the sprouting characterized the morphological change. It was thus suggested that they might exert crucial roles at the early stage of angiogenesis. CONCLUSION: The present study demonstrates a global profile of gene expression during endothelial capillary morphogenesis, and the results provide us much information about the molecular mechanisms of angiogenesis, with which further evaluation of individual genes can be conducted.

Determination of the Critical Temperature and Critical Pressure of Five Compounds

The critical properties of five compounds, including propanal,butanal, 1-pentanal, 2-methel butanal and trimer of ethanal, weredetermined for the first time by a new capillary quick-flow method.The apparatus was improved with a capillary tube and checked withhexane and 10heptene as standard reagents. The experimental resultsproved that the determination of critical properties by quick-flowmethod with a capillary tube apparatus was successful.

Meniscus behaviors and capillary pressures in capillary channels having various cross-sectional geometries

A numerical study has been conducted to simulate the liquid/gas interface(meniscus) behaviors and capillary pressures in various capillary channels using the volume of fluid(VOF) method. Calculations are performed for four channels whose cross-sectional shapes are circle, regular hexagon, square and equilateral triangle and for four solid/liquid contact angles of 30°, 60°, 120° and 150°. No calculation is needed for the contact angle of 90° because the liquid/gas interface in this case can be thought to be a plane surface. In the calculations, the liquid/gas interface in each channel is assumed to have a flat surface at the initial time, it changes towards its due shape thereafter, which is induced by the combined action of the surface tension and contact angle. After experiencing a period of damped oscillation, it stabilizes at a certain geometry. The interface dynamics and capillary pressures are compared among different channels under three categories including the equal inscribed circle radius, equal area, and equal circumscribed circle radius. The capillary pressure in the circular channel obtained from the simulation agrees well with that given by the Young–Laplace equation, supporting the reliability of the numerical model. The channels with equal inscribed circle radius yield the closest capillary pressures, while those with equal circumscribed circle radius give the most scattered capillary pressures,with those with equal area living in between. A correlation is developed to calculate the equivalent radius of a polygonal channel, which can be used to compute the capillary pressure in such a channel by combination with the Young–Laplace equation.

Study of Competitive Chelating Reaction between Lanthanum and Tribromoarsenazo in the Medium of Weak Acid by Capillary Zone Electrophoresis

Two kinds of metal chelates of rare earth elements reacted with tribrimoarsenazo formed under the condition of critic acid were observed by simultaneous technique of capillary electrophoresisphotothermal interference spectrometry. The tendency of the conversion between these chelates as functions of the mole ratio of the reagent and the metal, pH value and the elapsing time was investigated. Kinetic equation of competitive chelating reaction between the TBA-La (Ⅲ) and La (Ⅲ) -critic acid were established. It was found that the competitive chelating reaction follows secondorder kinetics, for this second-order reaction, k=5.55 L·mol-1·S-1.

Simultaneous determination of four triterpenoid saponins and two liganoids in the roots of Ilex pubescens by RP-HPLC-DAD

A reversed-phase high performance liquid chromatography （RP-HPLC） method with diode array detector （DAD） has been established to simultaneously determine six bioactive compounds in the roots ofllex pubescens, namely tortoside A, （＋）-syringaresinol, ilexsaponin B3, ilexsaponin A1, ilexsaponin B1, ilexgenin A. The RP-HPLC assay was performed on a reversed-phase C18 column with a gradient elution. The mobile phase consisted of acetonitrile and water containing 0.1% （v/v） phosphoric acid. The flow rate was 1.0 mL/min and the detection wavelength was set at 210 nm. The six marker constituents were separated well with good linearity （r2〉0.9996）, precision, stability and repeatability. The overall recoveries were in the range of 99.00%-104.52%. Cluster analysis was employed to analyze 15 batches of samples. The result indicated this method provide an efficient way to perform quality control as well as a scientific rationale for the Geo-authentication of I. pubescens.

A virtual 3D interactive painting method for Chinese calligraphy and painting based on real-time force feedback technology

A novel 3D interactive painting method for Chinese calligraphy and painting based on force feedback technology is proposed. The relationship between the force exerted on the brush and the resulting brush deformation is analyzed and a spring-mass model is used to build a model of the 3D Chinese brush. The 2D brush footprint between the brush and the plane of the paper or object is calculated according to the deformation of the 3D brush when force is exerted on the 3D brush. Then the 3D brush footprint is obtained by projecting the 2D brush footprint onto the surface of the 3D object in real time, and a complete 3D brushstroke is obtained by superimposing 3D brush footprints along the painting direction. The proposed method has been suc- cessfully applied in a virtual 3D interactive drawing system based on force feedback technology. In this system, users can paint 3D brushstrokes in real time with a Phantom Desktop haptic device, which can effectively serve as a virtual reality interface to the simulated painting environment for users.

Mao Zedong's “Three Worlds” Theory:Political Considerations and Value for the Times

Mao Zedong＇s theory of ＂the differentiation of three worlds＂ originated in his idea of ＂one intermediate zone＂ in the 1940s and 1950s, took initial shape with the idea of ＂two intermediate zones＂ in the 1960s and was officially formulated in the early 1970s. Taking national interests and the pursuit of sovereignty as its logical starting point, the law of the unity of opposites as its philosophical basis, the background of the Cold War as its historical platform, and opposition to hegemony as its diplomatic strategy, Mao Zedong advanced the well-known ＂three worlds＂ theory. As a hallmark achievement of China＇s diplomatic strategy and international relations theory, Mao＇s ＂three worlds＂ theory has a very special value for the times, especially with regard to its philosophy and principles in areas such as the principles of international ethics and justice, discourse power and national image, security mechanisms and strategic partnerships, and interdependence and cultural transcendence, all of which are precious ideological resources that we should cherish.