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Acta Biochimica et Biophysica Sinica 2006年第7期38卷 450-456页

作者： Tao HUANG Yuan-Zhu XIONG Ming-Gang LEI De-Quan XU Chang-Yan DENG Key Laboratory of Swine Genetics and Breeding,Ministry of agriculture,Huazhong agriculture university,Wuhan 430070,China Key Laboratory of Swine Genetics and Breeding Ministry of Agriculture Huazhong Agriculture UniversityWuhan 430070 China

To study the molecular basis of heterosis,suppression subtractive hybridization was used toinvestigate the differences in gene expression between porcine Longissimus dorsi of F1 hybrids LargeWhite×Meishan and their female parents *** two specific subtractive cDNA libraries,the clonesselected by reverse Northern high-density blot screening were chosen to clone full-length cDNA by rapidamplification of cDNA *** expression-upregulated gene for Meishan skeletal muscle,designated proteinphosphatase 1,catalytic subunit,beta isoform(PPPICB),was *** PPPICB contains an openreading frame encoding 327 amino acid residues with 13 and 1763 nucleotides in the 5′ and 3′ untranslatedregions,respectively.A DNA fragment of 721 nucleotides was amplified and a mutation that creates/disruptsa restriction site for endonuclease RsaI was *** derived amino acid sequence of PPPICB has highhomology with the PPPICB of three species,Mus musculus(99%),human(99%)and mouse(100%).Thetissue expression analysis indicated that the swine PPP1CB gene is generally expressed in most *** role of PPP1CB and its relation to porcine heterosis are discussed.

关键词： differential gene expression pig heterosis PPP1CB suppression subtractive hybridization

Wetting Rate and Clay Content Effects on Interrill Erosion in Ultisols of Southeastern China

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Pedosphere 2010年第1期20卷 129-136页

作者： YAN Feng-Ling, SHI Zhi-Hua , CAI Chong-Fa and LI Zhao-Xia Key Laboratory of Subtropical agriculture & Environment, Ministry of agriculture, Huazhong Agricultural university, Wuhan 430070 (China) Key Laboratory of Subtropical agriculture & Environment Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 (China)

An aggregate stability test and a simulated rainfall test were conducted on four representative Ultisols from southeastern China. The soils selected, with clay contents ranging between 117 and 580 g kg-1 , were derived from shale and Quaternary red clay. The stability of aggregates (2–5 mm in diameter) obtained from the soil samples were determined by the Le Bissonnais method. For determination of infiltration, runoff, and erosion, the soil samples were packed in 30 cm × 60 cm trays, wetted at rates of 2, 10, and 60 mm h-1 , and then exposed to simulated rainfall at 60 mm h-1 for 1 h. The results indicated that both aggregate stability and slaking caused by fast wetting increased with increasing clay content. The effect of wetting rate (WR) on infiltration and seal formation varied with clay contents. In the soil with low clay content (sandy loam), the infiltration rate was affected slightly by WR due to low aggregate stability and slaking. In the soils with medium clay content (silt clay loam and clay), WR affected infiltration significantly due to the high aggregate slaking force. In the soil with high clay content, the effect of WR on infiltration was significant, but not as evident as in the soils with medium clay content, which may be related to high aggregate stability by wetting partially compensating for slaking force. The effect of WR on soil loss was similar to that of runoff, but more pronounced. The findings from this study indicated that the relationship between wetting rate and clay content should be considered when predicting interrill erosion in Ultisols.

关键词： aggregate stability infiltration seal formation

Effects of sulfur dioxide on growth， gas exchange rate and leaf sulfur content of massion pine seedlings

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Journal of Environmental Sciences 1994年第3期6卷 268-276页

作者： Yang Liang United Graduate School,Tokyo university of agriculture and Technology,Fuchu,Tokyo 183,Japan Takeshi Izuta Tsumugu Totsuka (Department of Environmental Sciences and Resources,Faculty of agriculture,Tokyo Universtiy of agriculture and Technology,

The effects of sulfur dioxide(SO_2) on the dry weight growth gas exchange rate and leaf sulfur content of massion pine(Pinus massoniana Lamb. )were investigated. The results obtained in this study show that the dry weight growth and net photosynthetic rate of masson pine seedlings are reduced by exposure to SO_2 at ≥100 ppb. From these results,one of the main causes in the dieback of masson pine forest reported in Chongqing,China may be relatively high concentrations of atmospheric SO_2 in the relevant area.

关键词： sulfur dioxide(SO_2),Pinus massoniana Lamb. dry weight growth gas exchange rate leaf sulfur content.

CELLULAR SUBSTANCE EXUDATION AND SEED VIGOUR

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Journal of Northeast Forestry university 1992年第1期3卷 37-41页

作者： Chen Wenbin Zhao KentianNortheast Forestry universityShang JieNortheast agriculture university Northeast Forestry university China Northeast agriculture university China

In this paper, seeds of pinus koraiensis which has a characteristic of deep dormancy were selected as an experiment material, and the relation of cellular substance exudation to seed vigour is discussed based on the dormant state, the different measuring parts and the imbibed state of seeds before testing, as well as on the respiration of embryo and endosperm. The major measured results arc as follows: (1) After soaking for 24h, the dry embryo conductivity of sccdlot L is greater that than of sccdlot H: (2) The substance exudation of dry embryo of sccdlot H is less than that of sccdlot L; (3) After seeds imbibed, the substance exudation of dormant embryo of sccdlot H is more than that of sccdlot L; (4) After germination hastening treatment, the substance exudation of H embryos is greater than that of L embryos; (5) After artificially accelerated ageing treatment, the embryo conductivity of imbibed seeds has a positive correlation with seed vigour.

关键词： Cellular substance exudation Seed vigour Seed viability Self-repairing capability of cell membrane

RESERVOIR DESCRIPTION BY USING A PIECEWISE CONSTANT LEVEL SET METHOD

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Journal of Computational Mathematics 2008年第3期26卷 365-377页

作者： Hongwei Li Center for Integrated Petroleum Research,university of Bergen,norway Department of Mathematics,Capital Normal university,Beijing 100037,China Xuecheng Tai Department of Mathematics,university of Bergen,norway Division of Mathematical Sciences,School of Physical and Mathematical Sciences,Nanyang Technological university,Singapore Sigurd Ivar Aanonsen Center for Integrated Petroleum Research,university of Bergen,norway Department of Mathematics,university of Bergen,norway Center for Integrated Petroleum Research University of Bergen Norway Belting Department of Mathematics University of Bergen Norway Belting

We consider the permeability estimation problem in two-phase porous media flow. We try to identify the permeability field by utilizing both the production data from wells as well as inverted seismic data. The permeability field is assumed to be piecewise constant, or can be approximated well by a piecewise constant function. A variant of the level set method, called Piecewise Constant Level Set Method is used to represent the interfaces between the regions with different permeability levels. The inverse problem is solved by minimizing a functional, and TV norm regularization is used to deal with the ill-posedness. We also use the operator-splitting technique to decompose the constraint term from the fidelity term. This gives us more flexibility to deal with the constraint and helps to stabilize the algorithm.

关键词： Inverse problem Level set method Piecewise constant Operator splitting,Reservoir description

Morphometric relationships and reproductive maturation of the mudskipper, Periophthalmus barbarus from subsistence catches in the mangrove swamps of IMO estuary, Nigeria

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Journal of Environmental Sciences 2002年第2期14卷 221-226页

作者： MFON T. UDO (Department of Fisheries and Aquaculture, Faculty of agriculture, university of Uyo, PMB 1017, Akwa Ibom State, Nigeria. Department of Fisheries and Aquaculture Faculty of Agriculture University of Uyo PMB 1017 Akwa Ibom State 尼日利亚

From April 1992 and March 1993, morphometric characteristics and reproductive maturation were studied in Periophthalmus barbarus from subsistence catches in the mangrove swamps of Imo estuary. Morphometric equations for males and females at different stages of ovarian maturation are presented. Generally males were significantly heavier in weight than females, but the latter were heavier than the former of the same body length. Females with developing and mature ovaries were generally heavier than immature females of the same length. Analyses of the gonadosomatic index and percentage of mature males and females indicate all year\|round breeding such that: February\|May was spawning, June\|October postspawning and November to January recovery period. Fecundity varied between 900 and 23933 eggs per spawn and increased with fish size.

关键词： periophthalmus barbarus morphometric relationships reproductive maturation mangrove swamps Imo estuary Nigeria

Effects of free iron oxyhydrates and soil organic matter on copper sorption-desorption behavior by size fractions of aggregates from two paddy soils

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Journal of Environmental Sciences 2009年第5期21卷 618-624页

作者： WANG Fang, PAN Genxing, LI Lianqing Institute of Resource, Ecosystem and Environment of agriculture, Nanjing Agricultural university, Nanjing 210095, China. Institute of Resource Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China

Effects of free iron oxyhydrates （Fed） and soil organic matter （SOM） on copper （Cu^2＋） sorption-desorption behavior by size fractions of aggregates from two typical paddy soils （Ferric-Accumulic Stagnic Anthrosol （Soil H） and Gleyic Stagnic Anthrosol （Soil W）） were investigated with and without treatments of dithionite-citrate-bicarbonate and of H2O2. The size fractions of aggregates were obtained from the undisturbed bulk topsoil using a low energy ultrasonic dispersion procedure. Experiments of equilibrium sorption and subsequent desorption were conducted at soil water ratio of 1：20, 25℃. For Soil H, Cu^2＋ sorption capacity of the DCB-treated size fractions was decreased by 5.9% for fine sand fraction, by 40.4% for coarse sand fraction, in comparison to 2.9% for the bnlk sample. However, Cu^2＋ sorption capacities of the H2O2-treated fractions were decreased by over 80% for the coarse sand fraction and by 15% for the clay-sized fraction in comparison to 88% for bulk soil. For Soil W, Cu^2＋ sorption capacity of the DCB-treated size fraction was decreased by 30% for the coarse sand fraction and by over 75% for silt sand fraction in comparison to 44.5% for the bulk sample. Cu^2＋ sorption capacities of the H2O2-treated fractions were decreased by only 2.0% for the coarse sand fraction and by 15% for the fine sand fraction in comparison to by 3.4% for bulk soil. However, Cu^2＋ desorption rates were increased much in H2O2-treated samples by over 80% except the clay-sized fraction （only 9.5%） for Soil H. While removal of SOM with H2O2 tendend to increase the desorption rate, DCB- and H2O2-treatments caused decrease in Cu^2＋ retention capacity of size fractions, Particularly, there hardly remained Cu^2＋ retention capacity by size fractions from Soil H after H2O2 treatment except for clay-sized fraction. These findings supported again the dominance of the coarse sand fraction in sorption of metals and the preference of absorbed metals bound to SOM in differently stabilized

关键词： paddy soils Cn^2+ sorption-desorption soil organic matter free iron oxyhydrates size fraction of aggregates

Effect of molecular weight of dissolved organic matter on toxicity and bioavailability of copper to lettuce

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Journal of Environmental Sciences 2010年第12期22卷 1960-1965页

作者： Xudong Wang,Xianni Chen,Shuai Liu,Xizu Ge College of Resource and Environment,Northwest agriculture and Forestry university,Shaanxi 712100,China College of Resource and Environment Northwest Agriculture and Forestry University Shaanxi 712100 China

To clarify the effects of molecular weight of dissolved organic matter （DOM） on the toxicity and bioavailability of copper （Cu） to plants, DOM extracted from chicken manure was ultra-filtered into four fractions according to their molecular weights by means of sequential-stage ultrafiltration technique. Lettuce seeds were germinated by being exposed to the solutions containing Cu^2＋ with or without different fractions of DOM. The concentration of copper in roots, leaves, sprouts and the length of roots were investigated. The results showed that not all fractions of DOM could improve copper availability or toxicity. The fraction of DOM with larger molecular weight more than 1 kDa had higher complexation stability with Cu^2＋ and caused lower concentration of free Cu^2＋ ion in the solution of copper plus the fraction, resulting in lower availability and toxicity of copper to lettuce, but the fraction with molecular weight less than 1 kDa had the opposite function. Therefore, the molecular weight of 1 kDa may be the division point to determine DOM to increase or decrease copper availability and toxicity.

关键词： fraction of dissolved organic matter complexation stability coooer availability

Relation of lead adsorption on birnessites with different average oxidation states of manganese and release of Mn^(2+)/H^+/K^+

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Journal of Environmental Sciences 2009年第4期21卷 520-526页

作者： ZHAO Wei, FENG Xionghan, TAN Wenfeng, LIU Fan, DING Shuwen Key Laboratory of Subtropical agriculture Resource & Environment, Ministry of agriculture of China, Huazhong Agricultural university, Wuhan 430070, China. Key Laboratory of Subtropical agriculture Resource & Environment Ministry of Agriculture of China Huazhong Agricultural University Wuhan 430070 China

The characteristics of Pb^2＋ adsorption on the surface of birnessites with different average oxidation states （AOS） of Mn, synthesized under acidic and alkali conditions, were investigated. The results indicated that the amount of adsorbed Pb^2＋ increased with the increase of Mn AOS in birnessites. The amount of Pb〉 adsorbed positively correlated with the amount of released Mn^2＋, H^＋, and K^＋（r = 0.9962 〉 0.6614, n = 14, ct = 0.01）. The released Mn^2＋, H^＋, and K^＋ were derived mostly from the corresponding cations adsorbed on the vacant sites. The maximum amount of adsorbed Pb^2＋ increased with the increasing vacant cation sites, leading to an increase of the total amount of released Mn^2＋, H^＋, and K^＋, and the increased likelihood for two Pb^2＋ adsorbed in the region of one side of a vacant site.

关键词： pb^2+ adsorption birnessite vacant site cation release