期刊文献+
共找到19篇文章
< 1 >
每页显示 20 50 100
中华蜜蜂活框标准化饲养技术
1
《当代农村》 2000年第3期31-32,共2页
关键词 中华蜜蜂 标准化饲养 过箱技术
原文传递
中华蜜蜂活框标准化饲养技术要点
2
《当代农村》 2000年第2期37-37,共1页
关键词 中华蜜蜂 标准化饲养技术 过箱技术 过箱后管理
原文传递
国务院办公厅关于加强中央企业安全生产工作的通知
3
《海南省人民政府公报》 2004年第13期10-11,共2页
各省、自治区、直辖市人民政府,国务院各部委、各直属机构:中央企业(国资委代表国务院履行出资人职责的企业,下同)是国有经济的重要组成部分。搞好中央企业的安全生产工作,对保障国民经济平稳较快发展,促进全国安全生产形势的稳定好转... 各省、自治区、直辖市人民政府,国务院各部委、各直属机构:中央企业(国资委代表国务院履行出资人职责的企业,下同)是国有经济的重要组成部分。搞好中央企业的安全生产工作,对保障国民经济平稳较快发展,促进全国安全生产形势的稳定好转具有重要意义。当前,中央企业的安全生产状况总体稳定,但重特大事故仍然时有发生。为进一步加强中央企业的安全生产工作,保护人民群众的生命和财产安全,经国务院同意,现就有关事项通知如下:一、落实中央企业安全生产主体责任。 展开更多
关键词 直辖市人民政府 国务院各部委 国有经济 直属机构 预防为主 应急救援 生产许可证 属地管理 标准化活
下载PDF
国务院关于进一步加强安全生产工作的决定
4
《辽宁省人民政府公报》 2004年第4期10-15,共6页
各省、自治区、直辖市人民政府,国务院各部委、各直属机构:安全生产关系人民群众的生命财产安全,关系改革发展和社会稳定大局。党中央、国务院高度重视安全生产工作,建国以来特别是改革开放以来,采取了一系列重大举措加强安全生产工作... 各省、自治区、直辖市人民政府,国务院各部委、各直属机构:安全生产关系人民群众的生命财产安全,关系改革发展和社会稳定大局。党中央、国务院高度重视安全生产工作,建国以来特别是改革开放以来,采取了一系列重大举措加强安全生产工作。颁布实施了《中华人民共和国安全生产法》(以下简称《安全生产法》)等法律法规,明确了安全生产责任;初步建立了安全生产监管体系,安全生产监督管理得到加强;对重点行业和领域集中开展了安全生产专项整治。 展开更多
关键词 生产经营单位 生产经营秩序 国务院各部委 直辖市人民政府 直属机构 煤矿安全 企业生产安全 标准化活
下载PDF
Anticoagulation early after mechanical heart valve replacement 被引量:2
5
作者 Qin Chuan Xiao Yingbin Chen Lin 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第1期24-28,共5页
Objective: To explore the changes of coagulation activity and the characters of anticoagulation early after mechanical heart valve replacement. Methods: All patients only took warfarin orally for anticoagulation. Th... Objective: To explore the changes of coagulation activity and the characters of anticoagulation early after mechanical heart valve replacement. Methods: All patients only took warfarin orally for anticoagulation. The predicted international normalized ratio (INR) was 1.5 to 2.0. Several coagulation markers were monitored early after valve replacement. Complications associated with anticoagulation were recorded and analyzed. The patients were divided into three groups based on the number and position of mechanical valve prothesis, including group M (mitral valve replacement), group A (aortic valve replacement) and group D (mitral and aortic valve replacement).Comparison was made between the three groups. Results: Three events of mild cerebral embolism and five events of mild bleeding occurred during the early postoperative period. One patient suffered from mild cerebral embolism on the 4th day after operation, accompanied by large volume of pericardial drainage. Two patients with bleeding had lower INRs than predicted range. However, INR in one patient with mild cerebral embolism was in the predicted range. There was no significant difference in thrombo time (TT), activated partial thromboplastin time (APTT) and 1NR on the 3rd day after operation compared to those before operation; meanwhile, plasma fibrinogen (FIB) concentration was higher than that before operation (P〈0.05). 1NR had no significant changes on the 2nd day after the beginning of anticoagulation compared to that before operation; however, 1NR was significantly elevated on the 4th day (P〈0.05). Warfarin doses and INRs were similar among the three groups, but FIB concentrations in plasma were higher in groups M and D than in group A (P〈0.01). Conclusion: Hypercoagulabale state exists early after mechanical heart valve replacement. When anticoagulation begins is determined by the change of coagulation markers, not by the volume of chest or pericardial drainage. INR can not accurately reflect the coagulation state sometimes, especially during the first 3 days after anticoagulation. The number and position of mechanical valve prothesis could affect coagulation state. Therefore, anticoagulation therapy should be regulated accordingly. 展开更多
关键词 ANTICOAGULATION Mechanical heart valve replacement International normalized ratio WARFARIN
下载PDF
Co-residence in Denmark in 1801
6
作者 Hans J. Marker 《History Research》 2012年第3期219-232,共14页
The Danish 1801 census is available in a fully coded and standardised digital version. This makes it possible to analyse the living conditions of the Danes in new ways. A very central aspect of living conditions is ho... The Danish 1801 census is available in a fully coded and standardised digital version. This makes it possible to analyse the living conditions of the Danes in new ways. A very central aspect of living conditions is household and family. The census is divided by these lines and therefore calculations of household size and complexity are straight forward and this clearly gives one side of the picture. A totally different side is co-residence analysis. This is not straight forward, but because of the standardisation it is doable. By this means, you get a picture of the likelihood that a person of a given age group lives together with specific relatives. It gives an insight into a central part of living conditions and it gives a picture of differences between sexes and urbanisations. The paper brings the two ways of description together and shows that each has something to contribute to the picture of the Danes. 展开更多
关键词 the 19th century CENSUS CO-RESIDENCE Denmark HOUSEHOLD FAMILY POPULATION
下载PDF
One Year Minergie-A--Switzerlands Big Step towards Net ZEB
7
作者 Monika Hall 《Journal of Civil Engineering and Architecture》 2013年第1期11-19,共9页
The first available label standardizing a zero-balanced type of building is the Swiss Standard Minergie-A. The standard prescribes an annual net zero primary energy balance for heating, domestic hot water and ventilat... The first available label standardizing a zero-balanced type of building is the Swiss Standard Minergie-A. The standard prescribes an annual net zero primary energy balance for heating, domestic hot water and ventilation. Electricity consumption for appliances and lighting is excluded. Additionally, Minergie-A is the first standard worldwide which includes a requirement in regard to embodied energy. Based on an analysis of 39 Minergie-A buildings, this paper shows that a wide range of different energy concepts and embodied energy strategies are possible in the scope of the label. The basis of all Minergie-A buildings is a well-insulated building envelope. However, the step from the Swiss Standard Minergie-A to a Net ZEB (net zero energy building) standard which includes electricity consumption for appliances and lighting is not a very big one. Increasing the size of the photovoltaic system is sufficient in most cases. Anyway, some of the Minergie-A buildings evaluated are also Net ZEBs. In this paper, it is also shown that the net zero balance during the operational phase of Net ZEBs clearly outweighs the increased embodied energy for additional materials in a life cycle energy analysis. 展开更多
关键词 Net zero energy building net zero energy balance embodied energy life cycle energy primary energy.
下载PDF
Research on the Evaluation System of National Standardization
8
作者 Yang Feng Wang Jinyu 《China Standardization》 2010年第4期33-41,共9页
Standardization receives varied attention in different countries. Based on the Chinese national standardization status, this paper sets an evaluation system of national standardization on the principles of logic, comp... Standardization receives varied attention in different countries. Based on the Chinese national standardization status, this paper sets an evaluation system of national standardization on the principles of logic, comprehensiveness and operability, taking into account national standards and standardization activities. The evaluation system evaluates the national standardization development level through four aspects: standard development, standards implementation, standardization supporting measures, and participation in international standardization. This evaluation system provides a reasonable basis to evaluate the national standardization development level. The survey shows that if China wants to enhance its standardization development level, China needs to improve its standard development level, strengthen implication and application of standards, expand the standardization support measures and continuously improve the level of participation in international standardization. 展开更多
关键词 China STANDARDIZATION EVALUATION
下载PDF
Complex Standardization as the Factor of Flexibility and Competitive Ability
9
作者 Gustav Tomek Vera Vavrova 《Chinese Business Review》 2011年第6期438-444,共7页
Research, performed by the authors proved that one of the most significant factors affecting the increase in flexibility and competitive ability of a firm is the conceptual, complex intra-plant standardization. The en... Research, performed by the authors proved that one of the most significant factors affecting the increase in flexibility and competitive ability of a firm is the conceptual, complex intra-plant standardization. The enterprise implementing the standardization is capable of flexible responding to customer's demands for the assortment, accelerates considerably research, and offers satisfactory delivery terms. That means the selection of types of the input factors and the method how to use them, the selection of working procedures and procedures of intermediary consumption, definition of the relations in the process of control, rational structure of the final products etc.. The permanent innovative atmosphere is presupposed. 展开更多
关键词 STANDARDIZATION FLEXIBILITY COMPETITIVENESS EFFICIENCY
下载PDF
Experimental Research on Coke Wastewater Treatment by Hybrid Biological Reactor 被引量:1
10
作者 赵月龙 祁佩时 +1 位作者 孟昭辉 杨云龙 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期514-518,共5页
Phase hybrid biological reactor (HBR) was used in treating coke wastewater by adding submerging fiber-ball fillers in suspended growth activated sludge. The optimum operation parameters for the highest performance w... Phase hybrid biological reactor (HBR) was used in treating coke wastewater by adding submerging fiber-ball fillers in suspended growth activated sludge. The optimum operation parameters for the highest performance were determined. It was found that the hybrid biological reactor worked well for the coke wastewater treatment in terms of Chemical Oxygen Demand (COD), NH4+ -N and other refractory organic compounds removal efficiencies. Compared with conventional activated sludge system, the removal rate of COD and NH4+ -N and the nitrating rate were higher and more stable in the hybrid biological reactor. COD of effluent was less than 75 mg/L and the removal rate of COD and NH4+ -N could be up to 95.0% and 92.5% when COD of influent and NH4+ -N were less than 700 mg/L and 300 rag/L, respectively. In this way, the quality of effluent concentration could reach the first class of integrated wastewater discharge standard (GB8978-1996) (COD ≤100 mg/L). 展开更多
关键词 hybrid biological reactor coke wastewater operating parameters ammonia nitrogen refractoryorganic compounds
下载PDF
Study on the treatment of eutrophic water with a new integrative apparatus for water purification
11
作者 WANG Li-ping XUE Chun-yang +2 位作者 GUO Ying-qing CHEN Yi-zhong GAO Nai-yun 《Journal of Environmental Science and Engineering》 2009年第7期6-10,共5页
This paper studied the treatment of the landscape river in ChangZhou Scientific and Educational Town by a new integrative apparatus for water purification, which used ozone pre-oxidation-moDified clay-ozone biological... This paper studied the treatment of the landscape river in ChangZhou Scientific and Educational Town by a new integrative apparatus for water purification, which used ozone pre-oxidation-moDified clay-ozone biological activated carbon integrated process. The results indicate that the effectiveness of the algal removal with mentioned integrated process is much higher and the apparatus can operate stably. When the turbidity, chemical oxygen demand (CODMn), total nitrogen (TN), total phosphorus (TP) and algae densities of the raw water are 29-38 NTU, 7.45-7.79 mg/L, 2.496-2.981 mag/L, 0.237-0.255 mg/L and 5.78-7.94×10^8 cells/L respectively, it can be reduced to 0.8-1.7 NTU, 1.69-2.84 rag/L, 0.579-0.692mg/L, 0.013-0.038 mg/L, 0.06-0.38×10^8 cells/L. The average removal rates of turbidity, CODMn, TN, TP and algae density can reach 96.4%, 71.5%, 76.8%, 92.0% and 96.9% respectively. The treated water can meet the requirements of class Ⅰ- Ⅱ in Environmental Quality Standard, for Surface Water. 展开更多
关键词 integrative apparatus for water purification ozone preoxidation modified clay ozone biological activated carbon
下载PDF
Preparation of National CRMs of Active Compounds from Natural Products
12
作者 Duan Wenjuan Geng Yanling Wang Daijie Zhao Xianen Liu Jianhua Wang Xiao 《China Standardization》 2010年第3期19-25,共7页
According to the standard of GB/T1500.3-2008 and the guidelines of ISO/REMCO, the preparation of National Certified Reference Materials (CRMs) of active compounds was composed of the following two aspects: preparat... According to the standard of GB/T1500.3-2008 and the guidelines of ISO/REMCO, the preparation of National Certified Reference Materials (CRMs) of active compounds was composed of the following two aspects: preparation and certification. This paper presents an example of the preparation of biochanin A to illustrate the preparation of National CRMs of active compounds from natural products. Firstly, the target compound was extracted and purified from crude materials. Then, its chemical structure was identified by UV spectrum, IR spectrum, ESI-MS, and NMR. The purity of the compound was determined by HPLC with the area normalization method. The certified value assessed by comparing the purity values from six independent qualified laboratories and the value of uncertainty were given. Thermal analysis, residual solvent, homogeneity testing and stability testing was tested in the process. 展开更多
关键词 CRMs biochanin A natural products PREPARATION CERTIFICATION
下载PDF
Contamination of Water for Domestic Use and Human Consumption by Heavy Metals Derived from Mining Activity in Parral, Chihuahua, Mexico
13
作者 Luis Miguel Rodriguez Ever Torres +7 位作者 Luis Saenz Maria del Carmen Avitia Guillermo Rodriguez Eduardo Herrera Carmen Julia Navarro Guillermo Gonzalez Luis Lozoya Damaris Acosta 《Journal of Environmental Science and Engineering(A)》 2012年第3期286-294,共9页
Research was done with the objective of evaluating the quality of water supplied to the potable water system in Hidalgo Del Parral, which comes from two main supply sources: wells from "Valle del Verano", which pro... Research was done with the objective of evaluating the quality of water supplied to the potable water system in Hidalgo Del Parral, which comes from two main supply sources: wells from "Valle del Verano", which provide water to the east side of the city, and the Water Treatment Plant, which receives water from different mines and supplies the west side of the city. When this plant is overcome on its capacity of treatment, a part of the water from the mines is fed directly to the northwest part of the city. The metals lead (Pb), chromium (Cr), cadmium (Cd), zinc (Zn), and arsenic (As) were analyzed by atomic absorption (AA) technique, based on the United States Environmental Protection Agency (EPA) Method 7000B (Revision 2, February 2007). The digestion process was done according to the guidelines established in Method NMX-AA-051-SCFI-2001, Analysis of Water-Determination of Metals by Atomic Absorption, developed by the National Standardization Technical Committee for Environmental Protection (Mexico). The samples were collected from the following points: 13 wells and 2 re-pumping stations of "Valle del Verano", the inlet and outlet of the Water Treatment Plant, and domestic faucets. The east side of the city, supplied by the wells of "Valle del Verano", is metal-pollution free. The water that comes from the mines contains high concentrations of As, Zn, Cd and Pb, with levels that can get to 0.12, 32.6, 0.26 and 3.5 mg/L, respectively. This water pollution generated by mining can be concluded from the high levels found in the domestic samples in which, for several points, the concentrations exceed the parameters set by the current guideline. According to the results, it is vital to set a plan of remediation for the water that comes from the mines, because there is a great risk for health in the consumotion of this water. 展开更多
关键词 Heavy metals MINING water contamination.
下载PDF
Public Security Risk m Large Scale Activities and the Standardization Prospects
14
作者 Xiong Fei,Ma Na Yan Shaoqing research center or Shanghai Institute of Standardization. senior engineer,director or research center of standardization,Shanghai Institute of Standardization,secretary general of SAC/TC 269/SC 3 on third party logistics service,secretary general of SAC/TC 234/SC 1 on project management maturity assessment, 《China Standardization》 2010年第5期31-38,共8页
This paper generalizes the definition and its scope of large scale activity based on its current practice and supervision system in China, makes risk analysis during activities, and puts forward proposals on carrying ... This paper generalizes the definition and its scope of large scale activity based on its current practice and supervision system in China, makes risk analysis during activities, and puts forward proposals on carrying out relevant standardization works after discussions about the actuality and prospect of social security on large scale activities in China. 展开更多
关键词 Large Scale Activities Public Security STANDARDIZATION
下载PDF
Integrated approach of network pharmacology and chemometrics for quality control of Chinese patent medicine:A case study on Huo-Luo-San
15
作者 Meiling Zhu Jirong Zhang +4 位作者 Qiurong Zhang Yu Lin Xiaoyan Li Wen Xu Wei Xu 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2024年第9期819-836,共18页
Traditional Chinese medicine(TCM)has garnered significant global interest owing to its multi-component and multi-target theoretical framework and extensive therapeutic efficacy.However,the identification of quality ma... Traditional Chinese medicine(TCM)has garnered significant global interest owing to its multi-component and multi-target theoretical framework and extensive therapeutic efficacy.However,the identification of quality markers(Q-markers)remains a formidable challenge in TCM.Hence,this study aimed to integrate network pharmacology and chemometrics to identify Q-markers in Chinese patent medicine,with a focus on Huo-Luo-San(HLS)as a case study.HLS,a widely used powdered Chinese patent medicine in China,comprises a complex formula of 10 herbs,initially formulated during the Qing dynasty for treating fractures.Initially,13 components,chlorogenic acid,typhaneoside,isorhamnetin-3-O-neohesperidoside,cynaroside,notoginsenoside R_1,ginsenoside Rg_1,baicalin,berberine hydrochloride,ginsenoside Rb_1,dehydrocostus lactone,dioscin,imperatorin,and costunolide,were selected as phytochemical markers for each herb based on the Chinese Pharmacopoeia(2020 version),forming the“Herbs-Compounds-targets”network of HLS using network pharmacology.Subsequently,employing network pharmacology,the 13 HLS components were quantified using UPLC-QqQ-MS.Chromatographic conditions were optimized on a Waters Cortecs C_(18)column(2.1 mm×100 mm,1.6μm)with a gradient elution comprising 0.1%formic acid in water and acetonitrile.Analyte detection was performed in the multiple-reaction monitoring mode,and the method underwent validation for linearity,detection limit,precision,repeatability,stability,and accuracy.The validated method was then utilized to analyze the 13 components in 15 batches of HLS samples.Chemometric techniques,including hierarchical cluster analysis,principal component analysis,orthogonal partial least squares projection discriminant analysis,and box map analyses,were subsequently employed to identify the Q-markers.Ultimately,six components,baicalin,notoginsenoside R_1,berberine hydrochloride,dioscin,imperatorin,and chlorogenic acid,were selected as Q-markers for HLS.The integration of network pharmacology with chemometrics represented a novel approach for selecting Q-markers in Chinese patent medicine. 展开更多
关键词 Traditional Chinese medicine Quality markers Huo-Luo-San Network pharmacology CHEMOMETRICS
原文传递
国务院办公厅关于加强中央企业安全生产工作的通知
16
《国家国防科技工业局文告》 2004年第4期47-49,共3页
各省、自治区、直辖市人民政府,国务院各部委、各直属机构:中央企业(国资委代表国务院履行出资人职责的企业,下同)是国有经济的重要组成部分。搞好中央企业的安全生产工作,对保障国民经济平稳较快发展,促进全国安全生产形势的稳定好转... 各省、自治区、直辖市人民政府,国务院各部委、各直属机构:中央企业(国资委代表国务院履行出资人职责的企业,下同)是国有经济的重要组成部分。搞好中央企业的安全生产工作,对保障国民经济平稳较快发展,促进全国安全生产形势的稳定好转具有重要意义。当前,中央企业的安全生产状况总体稳定,但重特大事故仍然时有发生。为进一步加强中央企业的安全生产工作,保护人民群众的生命和财产安全,经国务院同意,现就有关事项通知如下: 展开更多
关键词 直辖市人民政府 国务院各部委 国有经济 直属机构 预防为主 应急救援 生产许可证 属地管理 标准化活
原文传递
Octahedral PtNi nanoparticles with controlled surface structure and composition for oxygen reduction reaction 被引量:4
17
作者 逯一中 Larissa Thia +3 位作者 Adrian Fisher Chi-Young Jung Sung Chul Yi 王昕 《Science China Materials》 SCIE EI CSCD 2017年第11期1109-1120,共12页
Controlling the surface structure and composi- tion at the atomic level is an effective way to tune the cat- alytic properties of bimetallic catalysts. Herein, we demon- strate a generalized strategy to synthesize hig... Controlling the surface structure and composi- tion at the atomic level is an effective way to tune the cat- alytic properties of bimetallic catalysts. Herein, we demon- strate a generalized strategy to synthesize highly monodis- perse, surfactant-free octahedral PtxNi1-x nanoparticles with tunable surface structure and composition. With increasing the Ni content in the bulk composition, the degree of concave- ness of the octahedral PtxNi1-x nanoparticles increases. We systematically studied the correlation between their surface structure/composition and their observed oxygen reduction activity. Electrochemical studies have shown that all the octa- hedral PtxNi1-x nanoparticles exhibit enhanced oxygen reduc- tion activity relative to the state-of-the-art commercial Pt/C catalyst. More importantly, we find that the surface struc- ture and composition of the octahedral PtxNi1-x nanoparti- cles have significant effect on their oxygen reduction activ- ity. Among the studied PtxNi1-x nanoparticles, the octahedral PtlNi1 nauoparticles with slight concaveness in its (111) facet show the highest activity. At 0.90 V vs. RHE, the Pt mass and specific activity of the octahedral PhNil nanoparticles are 7.0 and 7.5-fold higher than that of commercial Pt/C catalyst, re- spectively. The present work not only provides a generalized strategy to synthesize highly monodisperse, surfactant-free octahedral PtxNi1-x nanoparticles with tunable surface struc- ture and composition, but also provides insights to the struc- ture-activity correlation. 展开更多
关键词 PtNi OCTAHEDRAL CONCAVE surface structure oxygenreduction reaction
原文传递
Retrospective study on Professor Zhongying Zhou's experience in Traditional Chinese Medicine treatment on diabetic nephropathy 被引量:12
18
作者 Kelei Su Fangshi Zhu +3 位作者 Lizhong Guo Yao Zhu Wenlin Li Xingjiang Xiong 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第2期262-267,共6页
OBJECTIVE:To study and analyze the etiology and pathogenesis,diagnosis and prescription for cases of diabetic nephropathy(DN) treated by Professor Zhongying Zhou(Prof.Zhou) with the help of dada mining technique,so as... OBJECTIVE:To study and analyze the etiology and pathogenesis,diagnosis and prescription for cases of diabetic nephropathy(DN) treated by Professor Zhongying Zhou(Prof.Zhou) with the help of dada mining technique,so as to inherit his clinical experience and academic thoughts.METHODS:After pretreatment of the medical record information,statistical software SPSS 13.0 was used to analyze and process the standardized data using the descriptive analysis,cluster analysis and association rules.RESULTS:Ninety-four entries derived from Traditional Chinese Medicine(TCM) four-diagnostic information were selected.Through data mining,the highest frequency was yellow-thin-greasy tongue coating,followed by dark tongue,and then by thready-slippery pulse.The main self-conscious symptoms were limb numbness,dry mouth,frequent micturition,etc.With respect to pathogenesis,the etiology related to kidney reached 73.46%.The frequency of pathological factors for deficiency,blood stasis,heat,dampness,phlegm and dryness were 137.65%,80.25%,78.40%,48.77%,21.60%,and 14.20% respectively.A total of 236 kinds of herbs were used 2913 person times,averaging 17.98 herbs per prescription.CONCLUSION:The pathological location of DN is in the kidney.The pathogenesis of the disease is deficiency in origin and excess in superficiality,the former of which include deficiency of the liver and kidney,and deficiency of both Qi and Yin.The main pathological factors are blood stasis,heat,dampness,phlegm,and dryness;and they act upon each other to form the complex pathogenesis in terms of blood stasis-heat,dampness-heat,phlegm-heat,and dryness-heat.All the above factors are always crucial in the aggravation of DN throughout the whole course of its pathological evolution. 展开更多
关键词 Diabetic nephropathies RETROSPECTIVESTUDIES Data mining Clinical experience
原文传递
Predator-induced physiological responses in tadpoles challenged with herbicide pollution 被引量:1
19
作者 Pablo BURRACO Lidia Jimenez DUARTE Ivan GOMEZ-MESTRE 《Current Zoology》 SCIE CAS CSCD 2013年第4期475-484,共10页
Predators induce plastic responses in multiple prey taxa, ranging from morphological to behavioral or physiological changes. In amphibians, tadpoles activate plastic responses to reduce predation risk by reducing thei... Predators induce plastic responses in multiple prey taxa, ranging from morphological to behavioral or physiological changes. In amphibians, tadpoles activate plastic responses to reduce predation risk by reducing their activity rate and altering their morphology, specifically tail depth and pigmentation. Furthermore, there is now evidence that tadpoles' defenses are modi- fied when predators combine with other stressful factors such as pollutants or competitors, but our knowledge on the physiologi- cal responses underlying these responses is still scarce. Here we study physiological responses in Pelobates cultripes tadpoles exposed to a natural predator (larvae of the aquatic beetle Dytiscus circumflexus), non-lethal concentrations of herbicide (gly- phosate, 0.5 mg/L and 1.0 mg/L) or both factors combined. We measured corticosterone levels, standard metabolic rate, oxidative damage (TBARS) and activity of antioxidant enzymes, and immune response (via leukocyte count). Tadpoles reduced their corti- costerone concentration by ca. 24% in the presence of predator cues, whereas corticosterone did not change in the presence of glyphosate. Two enzymes involved in antioxidant response also decreased in the presence of predators (14.7% and 13.2% respec- tively) but not to glyphosate. Herbicide, however, increased the number of neutrophils and reduced that of lymphocytes, and had an interaction effect with predator presence. Standard metabolic rate did not vary across treatments in our experiment. Thus we show a marked physiological response to the presence of predators but little evidence for interaction between predators and low levels of herbicide. Multiple assessment of the physiological state of animals is important to understand the basis and conse- quences ofphenotypic plasticity 展开更多
关键词 Inducible defenses Physiological responses CORTICOSTERONE GLYPHOSATE Spadefoot toads Oxidative stress
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部