Trade-off between height growth and spring flushing in common beech (<Emphasis Type="Italic">Fagus sylvatica</Emphasis> L.)

• Introduction   

The annual development cycle of boreal and temperate trees results from an evolutionary trade-off between two opposing forces. These are namely, the adjustment of leaf phenology to the timing of frost occurrence at the beginning and/or the end of the growth season countered by an effective adjustment to the duration of the growth season to maximise photosynthesis and biomass production during the growing season.     

Spatial Inference of Nitrate Concentrations in Groundwater

We develop a method for multiscale estimation of pollutant concentrations, based on a nonparametric spatial statistical model. We apply this method to estimate nitrate concentrations in groundwater over the mid-Atlantic states, using measurements gathered during a period of 10 years. A map of the fine-scale estimated nitrate concentration is obtained, as well as maps of the estimated county-level average nitrate concentration and similar maps at the level of watersheds and other geographic regions. The fine-scale and coarse-scale estimates arise naturally from a single model, without refitting or ad hoc aggregation. As a result, the uncertainty associated with each estimate is available, without approximations relying on high spatial density of measurements or parametric distributional assumptions.     

金丝小枣插条中外源激素与内源激素的关系

该文从生理生化的角度对外源生长素（ＮＡＡ）在金丝小枣嫩枝插穗中的作用进行了研究。实验结果表明，外源生长素（ＮＡＡ）影响插条内的生理生化反应，大大提高了插条内源生长素（ＩＡＡ）的含量，同时能够维持内源脱落酸（ＡＢＡ）含量保持在一定的水平，调节了内源激素ＩＡＡ和ＡＢＡ两者之间的动态平衡，使得ＩＡＡ／ＡＢＡ值保持基本稳定；说明两者之间有着一定的协调作用，内源ＩＡＡ很大程序上影响形成层处细胞，使其分化出根原始细胞。     

Single-chain variable fragments antibody specific to <Emphasis Type="Italic">Corynespora cassiicola</Emphasis> toxin,cassiicolin, reduces necrotic lesion formation in <Emphasis Type="Italic">Hevea brasiliensis</Emphasis>

Corynespora leaf disease poses a serious threat to rubber cultivation because infected leaves develop necrotic lesions and abscise, leaving the tree unproductive. The destructiveness of Corynespora cassiicola has been largely attributed to cassiicolin, a protein toxin secreted by the fungus. Recombinant antibody technology offers hope to curtail the disease whereby single-chain variable fragments (scFv) specific to cassiicolin could bind and deactivate the toxin in genetically modified rubber trees that harbour the antibody gene. A scFv phage library was constructed from heavy and light variable chains of IgG from cassiicolin immunized Balb/C mice spleen. Biopanning of the phage library yielded a scFv clone with high specificity to cassiicolin. The nucleotide sequence and deduced amino acid sequence information of the scFv were obtained. Hemagglutinin (HA)-tagged scFv expressed in Escherichia coli is discerned as a band at ca. 30 kDa on SDS-PAGE, and the corresponding band was detected by anti-HA IgG on a Western immunoblot. Deactivation of cassiicolin by the affinity-purified scFv was demonstrated in a detached-leaf bio-assay on selected susceptible Hevea clones (PB 260, RRIM 2020, RRIM 901 and RRIM 929). The assay was also performed on clones that are relatively more resistant to the fungus (RRIM 600 and GT-1), and the results were as expected. Thus, we have successfully demonstrated that the cassicolin-specific scFv can effectively reduce cassicolin toxicity.     

低磷日粮中添加植酸酶对蛋鸡肠道形态结构的影响

试验旨在研究在低磷的玉米-豆粕型日粮中添加植酸酶对蛋鸡肠道形态结构的影响。选用18周龄体重、产蛋周龄相近的伊莎褐蛋鸡840羽,随机分成7组:正、负对照组及在负对照组基础上分别添加300、1000和10000U/kg的包衣状植酸酶、300U/kg的粉状及300U/kg的微丸状植酸酶(试验Ⅲ、Ⅳ、Ⅴ、Ⅵ和Ⅶ组)。结果表明:与负对照组相比,Ⅳ组的空肠绒毛高度得到了显著提高(P<0.05),Ⅲ、Ⅴ、Ⅵ和Ⅶ组与之相比无显著差异(P>0.05),但分别提高了16.49%、21.80%、15.73%以及17.29%;隐窝深度、绒毛高度/隐窝深度、黏膜厚度与之相比差异不显著(P>0.05)。各试验组间以及试验组与正对照组之间亦无显著差异(P>0.05)。因此,在低磷日粮中添加植酸酶对蛋鸡肠道结构具有一定的改善作用。     

Maturity and reproduction of goneplacid crab <Emphasis Type="Italic">Carcinoplax vestita</Emphasis> (Decapoda,Brachyura) in Tokyo Bay

ABSTRACT:     Sexual maturity, morphological sexual dimorphism, and reproduction of the goneplacid crab Carcinoplax vestita were investigated in Tokyo Bay, Japan, from November 2002 to October 2003. The puberty molt in males was evidenced by changes in the relative size of the chelipeds and merus of the walking legs, and was estimated to occur at a size range of 13.20–18.85 mm carapace length. Post-pubertal females were identified by the relative size of the abdomen and puberty was estimated to occur at a size range of 12.81–15.46 mm carapace length. Sexual dimorphism in C. vestita was observed in all features that showed secondary sexual characteristics. Monthly changes of gonad index in males, and of seminal receptacle index and occurrence of sperm plugs in females were synchronized, and indicated that mating was intense in spring. Ovaries began developing in March. Ovigerous females were found in all months except December, but were clearly more abundant between August and October. Fecundity ranged from 7800 to 57 000 mature oocytes per female per batch and was highly correlated with body size. The results suggest that some females may spawn more than one batch per year.     

菠萝蜜新品种‘海大1号’

 ‘海大1号’菠萝蜜是从干苞类菠萝蜜实生群体中通过单株选育而来的新品种。果实近椭圆形,黄绿色,平均单果质量2.48 kg。果肉金黄色,爽脆浓香,含可溶性固形物27.20%,维生素C 112.7 mg · kg^-1,可溶性糖292.30 g · kg^-1,可溶性蛋白质9.35 g · kg^-1,熟果粘胶少,可食率62.30%。5年生树平均株产38.45 kg。尤其适宜在广东雷州半岛等南亚热带区域栽培。     

Agent-based land-use models: a review of applications

Agent-based modelling is an approach that has been receiving attention by the land use modelling community in recent years, mainly because it offers a way of incorporating the influence of human decision-making on land use in a mechanistic, formal, and spatially explicit way, taking into account social interaction, adaptation, and decision-making at different levels. Specific advantages of agent-based models include their ability to model individual decision-making entities and their interactions, to incorporate social processes and non-monetary influences on decision-making, and to dynamically link social and environmental processes. A number of such models are now beginning to appear—it is timely, therefore, to review the uses to which agent-based land use models have been put so far, and to discuss some of the relevant lessons learnt, also drawing on those from other areas of simulation modelling, in relation to future applications. In this paper, we review applications of agent-based land use models under the headings of (a) policy analysis and planning, (b) participatory modelling, (c) explaining spatial patterns of land use or settlement, (d) testing social science concepts and (e) explaining land use functions. The greatest use of such models so far has been by the research community as tools for organising knowledge from empirical studies, and for exploring theoretical aspects of particular systems. However, there is a need to demonstrate that such models are able to solve problems in the real world better than traditional modelling approaches. It is concluded that in terms of decision support, agent-based land-use models are probably more useful as research tools to develop an underlying knowledge base which can then be developed together with end-users into simple rules-of-thumb, rather than as operational decision support tools. This paper arises from research conducted as part of the UK Research Councils’ RELU Programme (award number RES-224-25-0102). RELU is funded jointly by the Economic and Social Research Council, the Biotechnology and Biological Sciences Research Council and the Natural Environment Research Council, with additional funding from the Department for Environment, Food and Rural Affairs and the Scottish Executive Environment and Rural Affairs Department.     

Quantitative analysis of pattern of gonial proliferation during sexual maturation in Japanese scallop <Emphasis Type="Italic">Patinopecten yessoensis</Emphasis>

ABSTRACT:   This study was undertaken to describe and quantitatively analyze the pattern of development of gametes in the Japanese scallop Patinopecten yessoensis . Incorporation of 5-bromo-2'-deoxyuridine (BrdU) into gonial cells was used to quantitatively detect mitotically active gonial cells. Oogonia increased in number from November to December and decreased rapidly to March. A small number of oocytes was detected in November. Oocytes steadily increased in number and size up to March. The number of spermatogonia slightly increased from November to December, and increased markedly from January to March. Both ratios of BrdU-immunopositive gonial cells in the ovary and testis to gonial cells moderately increased from September to December. The ratio of BrdU-immunopositive spermatogonia to gonial cells drastically increased from January to February and kept an elevated level in March, whereas the oogonia started to disappear in January. The results suggest that the pattern of proliferation of gonial cells can be divided into two phases: (i) phase I, oogonia and spermatogonia slowly proliferate through the growing stage; and (ii) phase II, oogonia develop into oocytes and spermatogonia begin to proliferate rapidly through the mature and spawning stages. The proliferation of gonial cells is likely under different endocrine controls in phases I and II.     

Chemical synthesis of polypyrrole film and its adsorption capacity for aromatic polycarboxylic acids

Polypyrrole (PPy) film was prepared via in-situ chemical polymerization of pyrrole monomer on the surface of red-clay-brick (RCB) substrate. The deposited PPy film was characterized and used as an adsorbent for removal of benzene polycarboxylic acids from aqueous solutions. The effects of solution pH, contact time, initial concentration, and temperature on the adsorption process were systematically investigated to find the optimum operating conditions. Adsorption kinetic data were best fitted by pseudo-second order kinetic model. The adsorption equilibrium data were most represented by the Freundlich isotherm model. The maximum adsorption amounts of Trimellitic, Hemimellitic, and Pyromellitic acids were 189.27, 177.26, and 203.31 mg/g, respectively. The thermodynamic studies indicate that the adsorption was an endothermic and spontaneous process. Also, the PPy-RCB film was successfully regenerated using sodium hydroxide solution. The regenerated PPy-RCB can be reused for more than four successive cycles with a low reduction in adsorption efficiency.