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普通高中大文科“生态·生长”课堂教学实践探索
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作者 丛小利 《语文教学通讯(学术)(D)》 2017年第6期20-21,共2页
从现实背景、理论依据、内涵和基本原则、操作要领及实践意义五个维度对普通高中大文科"生态·生长"课堂模式进行诠释,进一步探索普通高中大文科课堂教学模式的发展可能性。
关键词 “生态·生长” 课堂 诠释 探索
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Effects of Probiotics on Growth Performance and Blood Biochemical Indexes of Cherry Valley Ducks 被引量:4
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作者 李小芬 杨晓志 +3 位作者 陶勇 张玲 顾文婕 袁旭红 《Agricultural Science & Technology》 CAS 2015年第8期1732-1734,1740,共4页
In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. To... In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight (P〈0.05) of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood (P〈0.05) and reduce the creatinine content and total cholesterol content in Cherry Valley ducks (P〉0.05); at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic. 展开更多
关键词 Cherry Valley duck Probiotic Growth performance Blood biochemicalindex Economic benefits
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RELATIONSHIP BETWEEN GROWTH AND MORPHOLOGY OF METARRHIZIUM ANISOPLIAE IN BIOTRANSFORMATION OF STEROID 被引量:2
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作者 阳葵 李晓静 +2 位作者 王积分 段世铎 张鎏 《Transactions of Tianjin University》 EI CAS 2001年第1期1-6,共6页
The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled t... The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled to growth phases:the fractal dimension,a feature calculated from the morphological images,increases during the late lag phase and the early exponential phase,and culminates at a value near 2.4 at half of the exponential phase.This can be attributed to the marked change of rough and smooth pellet proportions during growth and the change can be well expressed by the fractal analysis of mycelial morphology.The mycelial morphology is also strongly related to the biotransformation activity:a mycelial sample was withdrawn from the culture to use for fractal analysis before the steroid substrate (16α,17α epoxy 4 pregnene 3,20 dione) was added;the higher fractal dimension corresponds to the higher conversion rate of steroid biotransformation.And the maximum of fractal dimension appeared prior to the maximum of biomass concentration.It is therefore possible to utilize the fractal dimension curve to supervise the fermentation process more timely and availably than to use the conventional biomass curve to do. 展开更多
关键词 metarrhizium anisopliae MORPHOLOGY GROWTH fractal dimension BIOTRANSFORMATION STEROID
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Studies on stand dynamic growth model for larch in Jilin in China 被引量:1
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作者 翁国庆 陈雪峰 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期323-326,共4页
The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had h... The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had high precision, and they could be used for the updating data of inventory of planning and designing and optimal decision of forest management. 展开更多
关键词 Stand Dynamics Growth Prediction Model
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Study on Application of Microbial Ecological Agents, Replacements for Antibiotics, in Weaned Piglet Production 被引量:1
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作者 乔利敏 乔富强 +4 位作者 关文怡 张京和 肖西山 姚华 杨久仙 《Agricultural Science & Technology》 CAS 2015年第4期757-760,共4页
In order to investigate the appIication effects of microbial ecoIogical agents as repIacements for antibiotics in weaned pigIets, a total of 120 28 d oId healthy Duroc &#215;Landrace &#215;Large White weaned pigIets... In order to investigate the appIication effects of microbial ecoIogical agents as repIacements for antibiotics in weaned pigIets, a total of 120 28 d oId healthy Duroc &#215;Landrace &#215;Large White weaned pigIets with simiIar bogy weights and body fats and cIose birth dates were seIected. They were randomIy divided into three groups, incIuding controI group (CK), antibiotic group (A) and microbial ecoIogical agent group (MEA). The growth performance, health status and economic benefits of the weaned pigIets were measured. The resuIts showed that the A and MEA groups couId better enhance the immunity of weaned pigIets and improve the economic benefits in the whoIe experimental period compared to the CK group (P〈0.01). How-ever, there were no significant differences in pigIet immunity and economic benefits between the A and MEA groups (P〉0.05). It is indicated that the Rujunbao, a mi-crobial ecoIogical agent, can be promoted in weaned pigIet production as a repIace-ment for antibiotic. 展开更多
关键词 Microblal ecological agent Weaned piglet Growth performance Disease resistance Economic benefit
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Response of Growth and Water Use Efficiency of Spring Wheat to Whole Season CO_2 Enrichment and Drought 被引量:9
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作者 吴冬秀 王根轩 +2 位作者 白永飞 廖建雄 任红旭 《Acta Botanica Sinica》 CSCD 2002年第12期1477-1483,共7页
Whole_growing season pot experiments were conducted to examine the response of growth and water use efficiency ( WUE ) of spring wheat ( Triticum aestivum L. cv. Gaoyuan 602) to CO 2 enrichment. Wheat plants wer... Whole_growing season pot experiments were conducted to examine the response of growth and water use efficiency ( WUE ) of spring wheat ( Triticum aestivum L. cv. Gaoyuan 602) to CO 2 enrichment. Wheat plants were grown in open_top chambers (OTCs) subject to two concentrations of CO 2 ()(350 and 700 μL/L, hereafter 'ambient' and 'elevated' respectively) and three soil water levels (80%, 60% and 40% field water capacity ( FWC ), hereafter 'high soil moisture', 'medium soil moisture' and 'low soil moisture' respectively). Elevated CO 2 greatly increased leaf net photosynthesis ( Pn ) at all three soil water levels. The Pn of plants growing under elevated was 22% lower than that of plants growing at ambient when measured with the same (700 μL/L). Plant growth was enhanced by elevated throughout the growing season, with an increase of 14.8% in shoot dry weight at harvest under high soil moisture, and leaf area was increased by about 20% at all three soil water levels. Elevated in combination with high soil moisture increased the ratio of plant shoot dry weight to height by 15.7%, while this ratio was decreased by over 50% when plants were subject to drought. Elevated also increased the water use efficiency of wheat, mainly due to decreases in transpiration and cumulative consumption of water, and an increase in shoot dry weight, with the biggest value of 30% occurring at high soil water moisture level. Compared to high soil moisture, drought decreased shoot dry weight by 72% under ambient , and by 76% under elevated . Similarly, drought also reduced WUE by 19% under ambient , and 23% under elevated . Our results indicate that: (1) elevated can increase the photosynthetic rates, growth and WUE of wheat plants; (2) long_term exposure to high may result in lower photosynthetic capacity; (3) high stimulates plants lateral growth more than vertical growth; (4) the effects of CO 2 enrichment on plants depend on soil water status, with plants benefiting more from CO 2 enrichment if sufficient water is supplied; and (5) drought may cause relatively more reduction in plant growth and WUE under future elevated conditions. 展开更多
关键词 CO 2 open_top chamber water use efficiency Triticum aestivum DROUGHT
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Simulation Study on the Alkalized-salinized Grassland Ecosystem in the Songnen Plain 被引量:1
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作者 尚宗波 高琼 李建东 《Acta Botanica Sinica》 CSCD 2001年第6期624-630,共7页
Using Object-oriented design and a new programming language JAVA, a physically-based model was built to simulate the hydrological, alkalization/de-alkalization and salinization/desalinization processes in soil. Furthe... Using Object-oriented design and a new programming language JAVA, a physically-based model was built to simulate the hydrological, alkalization/de-alkalization and salinization/desalinization processes in soil. Furthermore, a process-based model was built to evaluate the dynamics of four herbaceous ecosystems (including dynamics of above-ground biomass, below-ground biomass, and litter biomass), each dominated by Aneurolepidium chinense (Trin.) Kitag., Chloris virgata Sw., Puccinellia tenuiflora (Turcz.) Scribn. et Merr. and Suaeda glauca Bunge. This model is a daily-time step model, suitable for simulating hydrological, alkalization/de-alkalization and salinization/desalinization processes of heterogeneous soil, and growth dynamics of different grassland communities. With climatic data and experimental data of Changling Experimental Site in Jilin Province, the soil moisture content (in 1991, 1996, 1997 and 1998), soil salt concentration, exchangeable cation percentage and pH in soil and growth dynamics of these four sorts of grassland communities (in 1991) were simulated and the results were verified to be in accord with observed data. 展开更多
关键词 alkalinized-salinized grassland hydrological process alkalization/de-alkalization processes salinization/desalinization processes growth dynamics ecological model
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Mechanism of Nutrient Silicon and Water Temperature Influences on Phytoplankton Growth 被引量:3
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作者 杨东方 高振会 +2 位作者 孙培艳 李梅 曲延峰 《Marine Science Bulletin》 CAS 2006年第2期49-59,共11页
This paper analyzed how nutrient silicon and water temperature influenced the variation of phytoplankton growth and the change of its assemblage structure, and probed the different characteristics of the variation of ... This paper analyzed how nutrient silicon and water temperature influenced the variation of phytoplankton growth and the change of its assemblage structure, and probed the different characteristics of the variation of phytoplankton growth and the different profiles of the change of its assemblage structure influenced by nutrient silicon and water temperature. Taking Jiaozhou Bay for example, this paper showed the process of both the variation of phytoplankton growth and the change of its assemblage structure, unveiled the mechanism of nutrient silicon and water temperature influencing the variation of phytoplankton growth and the change of its assemblage structure, and determined that nutrient silicon and water temperature were the motive power for the healthy running of the marine ecosystem. 展开更多
关键词 SILICON water temperature phytoplankton growth assemblage structure mechanism
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Response of seedlings of different tree species to elevated CO2 in Changbai Mountain 被引量:1
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作者 王淼 李秋荣 +1 位作者 代力民 姬兰柱 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期112-116,185,共页
Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadlea... Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 祄olmol-1) and ambient CO2 (400 祄olmol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species. The broad-leaf tree species were more sensitive to the elevated CO2 than conifer tree species. All seedlings showed a photosynthetic acclimation to long-term elevated CO2. 展开更多
关键词 Elevated CO2 Eco-physiological response Changbai Mountain
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Comparative Study of Rice Morphogenesis with Different Cultivation Methods
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作者 严定春 《Agricultural Science & Technology》 CAS 2012年第11期2424-2428,共5页
[Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characte... [Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characteristics of different rice culti- vars. [Method] Based on continuous field observation and destructive sampling over a growing season, detailed organ morphological data were obtained including leaf length, node number, plant height, tiller number, leaf angle, leaf area and specific leaf weight, to compare organ morphological differences among 4 rice cultivars of Baidao (indica), Jinnanfeng (japonica), 9325 (japonica) and 9915 (japonica) with 3 cultivation methods of field planting in Weigang, pot planting in Weigang, and field planting in Jiangpu. [Result] Maximum leaf length of each node gradually increased at the early growth stage and decreased at the later growth stage, the relationship between maximum leaf length and node position can be described by the equations y=a,,-~ and y=ax+b; node number, growth duration, leaf length and plant height of pot planting rice in Weigang were smaller than that of the other two field planting meth- ods; the relationship between plant height and sunshine duration, plant height and GDD (growing degree days) can be described by the equation y=ax+b, 19.23 ℃.d of GDD (≥10 ≥-d) and 8.12 h of sunshine duration were required to increase 1 cm of plant height; plant height, tiller number, and leaf area of Baidao were higher than that of the other 3 laponica rice cultivars, but the specific leaf weight and leaf angle were smaller. [Conclusion] Comparison of morphological characteristic differ- ences among rice cultivars is an important way to select water-saving and drought- tolerant rice varieties. In this study, the experimental results can be integrated into a rice functional-architectural model to simulate rice organ growth dynamics in a three- dimensional space, thereby providing reference for selecting water-saving and drought-tolerant rice cultivars. 展开更多
关键词 RICE LEAF Plant height Tiller number Leaf angle
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Uptake, Distribution and Accumulation of Copper in Two Ecotypes of Elsholtzia 被引量:16
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作者 JIANGLi-Ying YANGXiao-E +1 位作者 YEZheng-Qian SHIWei-Yong 《Pedosphere》 SCIE CAS CSCD 2003年第4期359-366,共8页
Two ecotypes of Elsholtzia, Elsholtzia splendens and E. argyi, are dominantplants growing on Cu and Pb-Zn smelters, respectively. Samples of the two ecotypes and thecorresponding soils from fields of a copper mining a... Two ecotypes of Elsholtzia, Elsholtzia splendens and E. argyi, are dominantplants growing on Cu and Pb-Zn smelters, respectively. Samples of the two ecotypes and thecorresponding soils from fields of a copper mining area and a Pb-Zn mining area ofZhejiang Province,China, were analyzed to investigate Cu or Zn tolerance of these two ecotypes. Effects of nine Culevels (0, 5, 10, 20, 40, 80, 160, 240 and 320 mg Cu L^(-1) as CuSO_4 centre dot 5H_O) on growth anduptake, translocation and accumulation of Cu in these two ecotypes were examined in a solutionculture experiment. The experimental results showed that dry weights (DW) of shoots and roots weredepressed, and growth of E. splendens was less depressed than that of E. argyi when treated with>= 5mg Cu L^(-1). Concentrations of Cu in shoots of E. splendens and E. argyi exceeded 1000 mg kg^(-1)DW at >= 40 mg Cu L^(-1). The maximum Cu accumulated in the shoots of Cu-treated E. splendens and E.argyi reached 101 and 142 mu g plant^(-1). Furthermore, analysis of plant samples from the fieldsshowed that these two ecotypes can tolerant excess heavy metals and produced high dry matter, and E.splendens can accumulate 11.7 mg Cu plant^(-1) grown on the Cu smelter. Therefore, E. splendens andE.argyi could be good plants for phytoremediation. 展开更多
关键词 COPPER Elsholtzia argyi Elsholtzia splendens
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A niche model to predict Microcystis bloom decline in Chaohu Lake, China 被引量:2
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作者 汪志聪 李钟杰 李敦海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第4期587-594,共8页
Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simp... Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simple and effective mathematical-ecological model to evaluate the growth status and predict the population dynamics of Microcystis blooms. In this study, phytoplankton were collected and identified from 8 sampling sites in Chaohu Lake every month from July to October, 2010. The niche breadth and niche overlap of common species were calculated using standard equations, and the potential relative growth rates of Microcystis were calculated as a weighted-value of niche overlap. In July, the potential relative growth rate was 2.79 (a.u., arbitrary units) but then rapidly declined in the following months to -3.99 a.u. in September. A significant correlation (R=0.998, P<0.01) was found in the model between the net-increase in biomass of Microcystis in the field and the predicted values calculated by the niche model, we concluded that the niche model is suitable for forecasting the dynamics of Microcystis blooms. Redundancy analysis indicated that decreases in water temperature, dissolved oxygen and total dissolved phosphorus might be major factors underlying bloom decline. Based on the theory of community succession being caused by resource competition, the growth and decline of blooms can be predicted from a community structure. This may provide a basis for early warning and control of algal blooms. 展开更多
关键词 Microcystis bloom niche breadth niche overlap predictive model Chaohu Lake
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Ecological functions of ciliated protozoa in marine ecosystem: effects of ammonium on the population growth of Euplotes vannus 被引量:1
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作者 许恒龙 Song Weibo +3 位作者 Zhu Mingzhuang Wang Mei Ma Honggang Xu Xiaozhong 《High Technology Letters》 EI CAS 2005年第4期432-436,共5页
The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate po... The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate populations in a concentration-dependent way. Statistical analvsis reveals that the population growth dynamics exposed to ammoniunt-N concentration over 100mg/L are significantly different from that in the control at P 〈 0.05 level. Linear regression determined that the 24h, 36h, 48h, 60h, 72h and 84h IC50 values of ammonium-N are 19.68, 201.51, 167.49, 47.86, 50.43 and 43.11 concentration over 100mg/L, respectively ( P 〈 0.05; pH 8.2; salinity 28 ppt; temperature, 25℃ ). The results indicate that the tolerance to ammonium in E. vannus is considerably higher than that of the larvae or juveniles of some metozoa, such as cuhured prawns and oysters. Therefore, it is believed that the high tolerance to ammonium is necessary for eiliated protozoa to play positive roles in maintaining and improving water quality in marine ecosystems, especially in the intensive aquacuhure waters with high-level ammonium. In addition, the correlation between /C50 values and exposure time was discussed. 展开更多
关键词 marine ciliates growth response AMMONIA MARICULTURE ECOTOXICOLOGY
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Ecological Characteristics of Soil Grown with Tricholoma Matsutake 被引量:1
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作者 XU GUANGBO FU WEIJIE +3 位作者 WEI TIEZHENG LI GUIHUA LIANG YUNJIANG QUAN MINGDAO and YANG SHURONG(Yianbian Agricultural College, Longjing, Jinn 133400 (China)) 《Pedosphere》 SCIE CAS CSCD 1997年第4期355-360,共6页
A 5-year study on the soil ecological environment of matsutake (Trihcholoma Matsutake) growing areas near Changbai Mountains showed that several factors, such as climate, parent material, organism and landform, which ... A 5-year study on the soil ecological environment of matsutake (Trihcholoma Matsutake) growing areas near Changbai Mountains showed that several factors, such as climate, parent material, organism and landform, which form the soil ecosystem provided suitable ecological environment for the formation and growth of matsutake. How to improve the construction and function of the soil ecosystem in order to utilize the natural resource continuously was also studied. 展开更多
关键词 ecological characteristics ECOSYSTEM matsutake SOIL
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A new record from China of epiphytic marine algae,Acrochaete leptochaete(Chaetophoraceae,Chlorophyta)with its primary experimental biology 被引量:1
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作者 邓蕴彦 汤晓荣 +1 位作者 丁兰平 连绍兴 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期350-355,共6页
Acrochaete leptochaete, a species in Chaetophoraceae (Chlorophyta), was observed during our recent laboratory culture of the macroalgae Chaetornorpha that was originally collected from an intertidal pool in Rongchen... Acrochaete leptochaete, a species in Chaetophoraceae (Chlorophyta), was observed during our recent laboratory culture of the macroalgae Chaetornorpha that was originally collected from an intertidal pool in Rongcheng, Shandong Province, China. This is the first record of this species in China. Its morphology, taxonomy, and distribution were introduced and discussed in detail. Isolated culture experiments at different temperatures (9-29℃) and light intensities (36-108 μmol/m^2.s) were also carried out. The culture-based observations have extended our knowledge of growth morphology and general biology of the species. 展开更多
关键词 Acroehaete leptochaete China GROWTH MORPHOLOGY new record TAXONOMY
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Preliminarily study on the maximum handling size, prey size and species selectivity of growth hormone transgenic and non-transgenic common carp Cyprinus carpio when foraging on gastropods 被引量:1
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作者 ZHU Tingbing ZHANG Lihong +4 位作者 ZHANG Tanglin WANG Yaping HU Wei OLSEN Rolf Eric ZHU Zuoyan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第4期1425-1433,共9页
The present study preliminarily examined the differences in maximum handling size, prey size and species selectivity of growth hormone transgenic and non-transgenic common carp Cyprinus carpio when foraging on four ga... The present study preliminarily examined the differences in maximum handling size, prey size and species selectivity of growth hormone transgenic and non-transgenic common carp Cyprinus carpio when foraging on four gastropods species( Bellamya aeruginosa, Radix auricularia, Parafossarulus sinensis and Alocinma longicornis) under laboratory conditions. In the maximum handling size trial, five fish from each age group(1-year-old and 2-year-old) and each genotype(transgenic and non-transgenic) of common carp were individually allowed to feed on B. aeruginosa with wide shell height range. The results showed that maximum handling size increased linearly with fish length, and there was no significant difference in maximum handling size between the two genotypes. In the size selection trial, three pairs of 2-year-old transgenic and non-transgenic carp were individually allowed to feed on three size groups of B. aeruginosa. The results show that the two genotypes of C. carpio favored the small-sized group over the large-sized group. In the species selection trial, three pairs of 2-year-old transgenic and non-transgenic carp were individually allowed to feed on thin-shelled B. aeruginosa and thick-shelled R. auricularia, and five pairs of 2-year-old transgenic and non-transgenic carp were individually allowed to feed on two gastropods species( P. sinensis and A. longicornis) with similar size and shell strength. The results showed that both genotypes preferred thin-shelled Radix auricularia rather than thick-shelled B. aeruginosa, but there were no significant difference in selectivity between the two genotypes when fed on P. sinensis and A. longicornis. The present study indicates that transgenic and non-transgenic C. carpio show similar selectivity of predation on the size-and species-limited gastropods. While this information may be useful for assessing the environmental risk of transgenic carp, it does not necessarily demonstrate that transgenic common carp might have lesser environmental impacts than non-transgenic carp. 展开更多
关键词 transgenic fish Cyprinus carpio L. fast growth predation ability prey selectivity
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Growth and maturity of Chiromantes dehaani in the Dazhi River estuary
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作者 韩莎 管卫兵 《Marine Science Bulletin》 CAS 2013年第1期51-65,共15页
Chiromantes dehaani, as one of the dominant species in intertidal regions of the Yangtze estuary, plays an important role in the ecosystem. To study allometry and maturity in different phases, morphological data had b... Chiromantes dehaani, as one of the dominant species in intertidal regions of the Yangtze estuary, plays an important role in the ecosystem. To study allometry and maturity in different phases, morphological data had been collected from October in 2009 to September in 2010. Morphologic data such as carapace, cheliped and abdomen were processed by cluster and piecewise linear regression analyses. Discriminat function and logistic curves were built to determine different phases and sizes at 50% maturity, respectively. The results showed that the cheliped width in males and abdomen width in females both presented obvious allometry. The sizes of 50% morphometric maturity occurred at 16.36 mm and 18.22 mm carapace width in males and females, respectively. The life history of males could be divided into three phases while that of females only had two phases according to different growth rates. A significant change in allometry of juvenile males with a break point was detected at 11.78 mm carapace width; carapace width of juvenile and adult females overlapped in a range of 13.04 - 18.64 mm. The crabs attained 50% physiological maturity at the size of 17.50 mm and 17.20 mm for females and males, respectively. For male, the size of morphological maturity was larger than that of physiological maturity, which was opposite to that of female. 展开更多
关键词 Chiromantes dehaani cheliped ABDOMEN allometric growth morphological maturity physiological maturity
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Metabolic rates and biochemical compositions of Apostichopus japonicus (Selenka) tissue during periods of inactivity 被引量:5
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作者 包杰 董双林 +3 位作者 田相利 王芳 高勤峰 董云伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期218-223,共6页
Estivation, hibernation, and starvation are indispensable inactive states of sea cucumbers Apostichopusjaponicus in nature and in culture ponds. Generally, temperature is the principal factor that induces estivation o... Estivation, hibernation, and starvation are indispensable inactive states of sea cucumbers Apostichopusjaponicus in nature and in culture ponds. Generally, temperature is the principal factor that induces estivation or hibernation in the sea cucumber. The present study provided insight into the physiological adaptations ofA. japonicus during the three types of inactivity (hibernation, estivation, and starvation) by measuring the oxygen consumption rates (Vo2) and biochemical compositions under laboratory conditions of low (3℃), normal (17℃) and high (24℃) temperature. The results show that the characteristics of A. japonicus in dormancy (hibernation and estivation) states were quite different from higher animals, such as fishes, amphibians, reptiles, and mammals, but more closely resembled a semi-dormant state. It was observed that the shift in the A. japonicus physiological state from normal to dormancy was a chronic rather than acute process, indicated by the gradual depression of metabolic rate. While metabolic rates declined 44.9% for the estivation group and 71.7% for the hibernation group, relative to initial rates, during the 36 d culture period, metabolic rates were not maintained at constant levels during these states. The metabolic depression processes for sea cucumbers in hibernation and estivation appeared to be a passive and an active metabolic suppression, respectively. In contrast, the metabolic rates (128.904-11.70 μg/g h) of estivating sea cucumbers were notably higher (107.85±6.31 μg/gh) than in starving sea cucumbers at 17℃, which indicated that the dormancy mechanism here, as a physiological inhibition, was not as efficient as in higher animals. Finally, the principle metabolic substrate or energy source of sea cucumbers in hibernation was lipid, whereas in estivation they mainly consumed protein in the early times and both protein and lipid thereafter. 展开更多
关键词 Apostichopus japonicus oxygen consumption rates chemical composition temperature periods of inactivity
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Growth Front Evolution of GaN Thin Films on Sapphire Substrate During HVPE 被引量:1
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作者 LU Dian-qing LI Xin-hua LIU Xue-dong 《Semiconductor Photonics and Technology》 CAS 2005年第4期221-224,共4页
The growth front evolution of GaN thin films deposited on sapphire substrate by hydride vapor phase epitaxity has been studied with atomic force microscope. The evolution of the surface morphology presents four featur... The growth front evolution of GaN thin films deposited on sapphire substrate by hydride vapor phase epitaxity has been studied with atomic force microscope. The evolution of the surface morphology presents four features of stage with the growth process. In initial growth stage, the surface is granular, and the typical grain diameter is about 250 nm for t =0.1 min. 3D growth plays a key role before the films come up to full coalescence, which causes a rough surface. After 0. 1 min the growth dimension decreases with the increase of lateral over growth, the surface roughness obviously decreases. From 0.4 min to 3 rain, the growth front roughness increases gradually, and the evolution of the surface roughness exhibits the characteristics of self-affined fractal. Beyond 3 min, the root-mean-square decreases gradually, which means the deposition behavior from hyper-2D growth gradually turns into layer growth mode with the increase of growth time. 展开更多
关键词 GAN Hydride vapor phase epitaxy Growth front evolution
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Stocking density affects the growth performance and metabolism of Amur sturgeon by regulating expression of genes in the GH/IGF axis 被引量:2
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作者 REN Yuanyuan WEN Haishen +1 位作者 LI Yun LI Jifang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期956-972,共17页
The effects of stocking density on the growth and metabolism of Amur sturgeon were assessed. Amur sturgeon were grown for 70 days at three dif ferent stocking densities(low stocking density, LSD: 5.5 kg/m^3; medium st... The effects of stocking density on the growth and metabolism of Amur sturgeon were assessed. Amur sturgeon were grown for 70 days at three dif ferent stocking densities(low stocking density, LSD: 5.5 kg/m^3; medium stocking density, MSD: 8.0 kg/m^3; and high stocking density, HSD: 11.0 kg/m^3), and the biometric index, muscle composition, and serum biochemical parameters were evaluated. In addition, pituitary, liver, and muscle samples were collected for gene cloning and expression analyses. After 70 days of growth, the fish maintained at HSD had significantly lower fi nal body weight and specifi c growth rate, and a higher feed conversion ratio than those of the fish in the MSD and LSD groups. The HSD group had the lowest lipid and protein concentrations in serum and muscle. The serum cortisol concentration increased significantly in the HSD group, indicating that the stress-response system was activated in these fish. There was no change in the concentration of serum insulin-like growth factor 2(IGF-2), while the concentrations of serum growth hormone(GH) and insulin-like growth factor 1(IGF-1) decreased in the HSD group. The full-length cDNAs of G H and IGF-2 genes(995-bp and 1 207-bp long, respectively), were cloned and analyzed. In the HSD group, the expressions of GH in the pituitary and growth hormone receptor( GHR) and IGF-1 in the liver were down-regulated at the end of the 70-day experiment. In the HSD group, the transcript level of IGF-2 significantly decreased in the liver, but did not change in muscle. Overall, our results indicated that a HSD negatively af fects the growth performance and leads to changes in lipid and protein metabolism in Amur sturgeon. The down-regulated expression of genes related to the GH/IGF axis may be responsible for the poor growth performance of Amur sturgeon under crowding stress. 展开更多
关键词 Amur sturgeon stocking density growth metabolism growth hormone (GH) insulin-like growth factor(IGF) AXIS
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