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Effects of live yeast on differential genetic and functional attributes of rumen microbiota in beef cattle

Journal of Animal Science and Biotechnology 2019年第4期10卷 1101-1107页

作者： Ibukun M.Ogunade Jerusha Lay Kenneth Andries Christina J.Mc Manus Frederick Bebe College of Agriculture Communities and the Environment Kentucky State University

Several studies have evaluated the effects of live yeast supplementation on rumen microbial population;however,its effect on differential microbial genes and their functional potential has not been described. Thus, this study applied shotgun metagenomic sequencing to evaluate the effects of live yeast supplementation on genetic and functional potential of the rumen microbiota in beef cattle. Eight rumen-cannulated Holstein steers were randomly assigned to two treatments in a cross-over design with two 25-day experimental periods and a 10-day wash-out between the two periods. The steers were housed in individual pens and fed 50% concentrate-mix and 50% red clover/orchard hay ad libitum. Treatments were(1) control(CON;basal diet without additive) and(2) yeast(YEA;basal diet plus 15 g/d of live yeast product). Rumen fluid samples were collected at 3, 6, and 9 h after feeding on the last d of each period. Sequencing was done on an Illumina Hi Seq 2500 platform. Dietary yeast supplementation increased the relative abundance of carbohydrate-fermenting bacteria(such as Ruminococcus albus, ***, R. bromii, and R. obeum) and lactate-utilizing bacteria(such as Megasphaera elsdenii, Desulfovibrio desulfuricans, and D. vulgaris). A total of 154 differentially abundant genes(DEGs) were obtained(false discovery rate < 0.01). Kyoto Encyclopedia of Genes and Genomes(KEGG) annotation analysis of the DEGs revealed that 10 pathways, including amino sugar and nucleotide sugar metabolism, oxidative phosphorylation, lipopolysaccharide biosynthesis, pantothenate and coenzyme A biosynthesis, glutathione metabolism, beta-alanine metabolism,polyketide sugar unit biosynthesis, protein export, ribosome, and bacterial secretory system, were enriched in steers fed YEA. Annotation analysis of the DEGs in the carbohydrate-active enzymes(CAZy) database revealed that the abundance of genes coding for enzymes belonging to glycoside hydrolases, glycosyltransferases, and carbohydrate bindi

关键词： Functional potential Live yeast Rumen

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[Advances in molecular networking technology for discovering emerging contaminants and transformation products]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 33-42页

作者： Xiao-Mei Tan Yu-Wei Zhang Zhao-Yu Jiao Nan-Yang Yu Si Wei State Key Laboratory of Pollution Control & Resource Reuse School of Environment Nanjing University Nanjing 210046 China.

Emerging contaminants and their transformation products are widely distributed in the environment. These pollutants carry unknown risks owing to their persistence, migration, and toxicity. The wide variety and complex structures of these substances render them difficult to identify using only target analysis. Suspect screening analysis can identify more substances than target analysis in a single run. However, this analysis method is based on limited data and cannot meet the growing demand for compound identification, especially for emerging contaminants and their transformation products with unknown information. The development of high-resolution mass spectrometry technology has promoted the applications of nontarget analysis in the environmental field, especially for identifying unknown transformation products. At present, the challenges of nontarget analysis include the difficulty of finding compounds of interest and their transformation products from complex data. Molecular networking calculates the similarity between mass spectra based on an improved cosine similarity algorithm. This method can cluster molecular families with similar structures, achieve visualization and a collection of massive mass spectral datasets, and promote the annotation of pollutants through networks and communities. Molecular networking can globally organize and systematically interpret complex tandem mass spectral datasets, providing a new direction for nontarget analysis. This technology was first used in proteomics and gradually introduced into metabolomics for the discovery of new natural products. Recently, it has been introduced into the environmental field for the study of various man-made chemicals, particularly for the discovery of emerging contaminants and their transformation products. In this paper, we introduce a molecular networking analysis method based on high-resolution tandem mass spectrometry and describe its applications in the nontargeted screening of emerging cont

关键词： emerging contaminants high-resolution tandem mass spectrometry molecular networking transformation products

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Urban energy consumption and related carbon emission estimation： a study at the sector scale

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frontiers of Earth Science 2013年第4期7卷 480-486页

作者： Weiwei LU Chen CHEN Meirong SU Bin CHEN Yanpeng CAI Tao XING State Key Joint Laboratory of environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Institute for Energy Environment and Sustainable Communities University of Regina Regina S4S 7H9 Canada Beijing Yanqing District Development and Reform Commission Beijing 102100 China

With rapid economic development and energy consumption growth, China has become the largest energy consumer in the world. Impelled by extensive international concern, there is an urgent need to analyze the character- istics of energy consumption and related carbon emission, with the objective of saving energy, reducing carbon emission, and lessening environmental impact. Focusing on urban ecosystems, the biggest energy consumer, a method for estimating energy consumption and related carbon emission was established at the urban sector scale in this paper. Based on data for 1996-2010, the proposed method was applied to Beijing in a case study to analyze the consumption of different energy resources （i.e., coal, oil, gas, and electricity） and related carbon emission in different sectors （i.e., agriculture, industry, construction, transportation, household, and service sectors）. The results showed that coal and oil contributed most to energy consumption and carbon emission among different energy resources during the study period, while the industrial sector consumed the most energy and emitted the most carbon among different sectors. Suggestions were put forward for energy conservation and emission reduction in Beijing. The analysis of energy consumption and related carbon emission at the sector scale is helpful for practical energy saving and emission reduction in urban ecosystems.

关键词： energy consumption carbon emission urban sector Beijing

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Development of a model-based flood emergency management system in Yujiang River Basin, South China

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frontiers of Earth Science 2014年第2期8卷 231-241页

作者： Yong ZENG Yanpeng CAI Peng JIA Jiansu MAO State Key Laboratory of Petroleum Resource and Prospecting College of Geosciences China Petroleum University Beijing 102249 China State Key Laboratory of Water environment Simulation School of Environment Beijing Normal University Beijing 100875 China Institute for Energy Environment and Sustainability Communities University of Regina Regina Sask S4S 7H9 Canada Appraisal Center for environment and Engineering Ministry of Environmental Protection Beijing 100012 China

Flooding is the most frequent disaster in China. It affects people＇s lives and properties, causing considerable economic loss. Flood forecast and operation of reservoirs are important in flood emergency management. Although great progress has been achieved in flood forecast and reservoir operation through using computer, network technology, and geographic information system technology in China, the prediction accuracy of models are not satisfactory due to the unavailability of real-time monitoring data. Also, real-time flood control scenario analysis is not effective in many regions and can seldom provide online decision support function. In this research, a decision support system for real-time flood forecasting in Yujiang River Basin, South China （DSS-YRB） is introduced in this paper. This system is based on hydrological and hydraulic mathematical models. The conceptual framework and detailed components of the proposed DSS-YRB is illustrated, which employs real-time rainfall data conversion, model-driven hydrologic forecasting, model calibration, data assimilation methods, and reservoir operational scenario analysis. Multi-tiered architecture offers great flexibility, portability, reusability, and relia- bility. The applied case study results show the development and application of a decision support system for realtime flood forecasting and operation is beneficial for flood control.

关键词： flood decision support system numericalmodeling scenarios analysis Yujiang River Basin

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Coupled planning of water resources and agricultural land-use based on an inexact-stochastic programming model

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frontiers of Earth Science 2014年第1期8卷 70-80页

作者： Cong DONG Guohe HUANG Qian TAN Yanpeng CAI MOE Key Laboratory of Regional Energy and environmental Systems Optimization Resources and Environmental Research Academy North China Electric Power University Beijing 102206 China State Key Laboratory of Water environment Simulation School of Environment Beijing Normal University Beijing 100875 China Institute for Energy Environment and Sustainable Communities University of Regina Saskatchewan S4S 7H9 Canada

Water resources are fundamental for support of regional development. Effective planning can facilitate sustainable management of water resources to balance socioeconomic development and water conservation. In this research, coupled planning of water resources and agricultural land use was undertaken through the develop- ment of an inexact-stochastic programming approach. Such an inexact modeling approach was the integration of interval linear programming and chance-constraint pro- gramming methods. It was employed to successfully tackle uncertainty in the form of interval numbers and probabil- istic distributions existing in water resource systems. Then it was applied to a typical regional water resource system for demonstrating its applicability and validity through generating efficient system solutions. Based on the process of modeling formulation and result analysis, the developed model could be used for helping identify optimal water resource utilization patterns and the corresponding agri- cultural land-use schemes in more, a number of decision three sub-regions. Further- alternatives were generated under multiple water-supply conditions, which could help decision makers identify desired management policies.

关键词： water resources management regional water system planning scenario analysis uncertainty

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Changes in Agricultural System as Farmers Adapt to Economic-Social and Climatic Changes in the Min Upriver Rural Areas in Western Sichuan,Southwestern China

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Journal of Mountain Science 2015年第3期12卷 747-758页

作者： ZHANG Long-jiang TANG Ya LIU Ben-hong Department of environment College of Architecture and EnvironmentSichuan University

Rapid economic growth in China has brought about great economic-social changes in rural areas, having considerable impact on the society in economy and environment. With a per capita possession of about 0.08 ha of cropland, Chinese farmers in rural areas adopt various ways in response to these changes in a bit to maintain their livelihood, wherein the agricultural system is facing one more options possible. To understand how rural communities have used different mechanisms to adapt to the economic and natural changes, we joined a survey in dry valleys of the Min upriver area under Maoxian county of western Sichuan province, southwestern China and visited the local people. Changes in the main crop cultivation have shown up an important means to keep up their household income. Farm households start seeking economic growth through diversified cultivating of cereal and economic crops in five lines, namely cereal, apple monoculture, apple and vegetables, plum and vegetables, mixed fruits and vegetables. These new lines mirror farmers' flexibility to cope with today's economic-social and climatic changes. The farming operation has changed all the more from a subsistence on grain to special agricultural products. Economic reforms in the early 1980 s motivated theprogress first in conversion of production from grain to fruits, and the desire to increase family income turned out to be an impetus for the subsequent events. At present, more farmers moving out of the rural areas, uneasy availability of labor force, increased opportunity cost of labors and their wages, increased farm size, and the urgent demand for the agricultural labor force, all these combine into the trend of the agricultural system of China on facing further economic-social reforms and reconstruction of the countryside across China.

关键词： Agricultural system Climate change Farmers Economic impacts Social change MinRiver

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Total phosphorus accident pollution and emergency response study based on geographic information system in Three Gorges Reservoir area

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frontiers of environmental Science & Engineering 2020年第3期14卷 113-125页

作者： Aifeng Zhai Xiaowen Ding Lin Liu Quan Zhu Guohe Huang MOE Key Laboratory of Resources and environmental System Optimization College of Environmental Science and EngineeringNorth ChinaElectric Power UniversityBeijing 102206China Institute for Energy Environment and Sustainable CommunitiesUniversity of ReginaS4S 7H9ReginaCanada

In recent years,sudden water pollution accidents in China's rivers have become more frequent,resulting in considerable effects on environmental ***,it is necessary to simulate and predict pollution *** and prediction provide strong support for emergency disposal and disaster *** paper describes a new two-dimensional water quantity and the quality model that incorporates a digital elevation model into the geographic information *** model is used to simulate sudden water pollution accidents in the main stream of the Yangtze River and Jialing River in the Chongqing section of the Three Gorges Reservoir *** sectional velocity distribution and concentration change of total phosphorus are then analyzed under four hydrological *** results show that the proposed model accurately simulates and predicts the concentration change and migration process of total phosphorus under sudden water pollution *** speed of migration and diffusion of pollutants is found to be greatest in the flood season,followed by the water storage period,drawdown season,and dry season,in that *** selection of an appropriate water scheduling scheme can reduce the peak concentration of river *** study enables the impact of pollutants on the ecological environment of river water to be alleviated,and provides a scientific basis for the emergency response to sudden water pollution accidents in the Three Gorges Reservoir area.

关键词： Sudden water pollution accident Total phosphorus Predictive model Contaminant simulation Water scheduling Measure

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Performance and microbial community analysis of an algal-activated sludge symbiotic system: Effect of activated sludge concentration

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Journal of environmental Sciences 2019年第2期31卷 121-132页

作者： Li Sun Wei Zuo Yu Tian Jun Zhang Jia Liu Ni Sun Jianzheng Li State Key Laboratory of Urban Water Resource and environment (SKLUWRE) School of EnvironmentHarbin Institute of Technology

It was focused on the effect of different sludge concentrations on the performances of an algal-activated sludge symbiotic system in terms of wastewater treatment, algal-activated sludge characteristics and community structure. The results showed that the highest nutrient removal efficiencies were obtained in the reactor R^2 with soluble chemical oxygen demand(sC OD), ammonia nitrogen(NH_4^+-N) and phosphate(PO_4^(3-)-P) removal efficiencies of(90.6 ± 2.3)%,(97.69 ± 2.6)% and(83.81 ± 2.3)%, respectively. Further investigation exhibited that sludge concentration has a great effect on the dissolved oxygen(DO) concentration, the pH, the growth of algae and the extracellular polymeric substance(EPS) production, which resulted in influencing the settleability and the performance of symbiotic system. The denaturing gradient gel electrophoresis(DGGE) analysis demonstrated that the sludge concentration had a selective power for particular members of algae. Meantime, the stimulated algal population would selectively excite the members of bacteria benefited for the formation of algal-bacterial *** variation of microbial compositions, which was influenced by the different sludge concentrations, might be ultimately responsible for the different treatment performances.

关键词： Algal-activated sludge symbiotic system Sludge concentration Wastewater treatment Algal and bacterial communities

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Aeration optimization through operation at low dissolved oxygen concentrations:Evaluation of oxygen mass transfer dynamics in different activated sludge systems

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Journal of environmental Sciences 2017年第5期29卷 224-235页

作者： Haitao Fan Lu Qi Guoqiang Liu Yuankai Zhang Qiang Fan Hongchen Wang Research Center for Low Carbon Technology of Water environment Renmin University of China School of environment Jinan University

In wastewater treatment plants（WWTPs）using the activated sludge process,two methods are widely used to improve aeration efficiency — use of high-efficiency aeration devices and optimizing the aeration control strategy. Aeration efficiency is closely linked to sludge characteristics（such as concentrations of mixed liquor suspended solids（MLSS）and microbial communities）and operating conditions（such as air flow rate and operational dissolved oxygen（DO）concentrations）. Moreover,operational DO is closely linked to effluent quality. This study,which is in reference to WWTP discharge class A Chinese standard effluent criteria,determined the growth kinetics parameters of nitrifiers at different DO levels in small-scale tests. Results showed that the activated sludge system could meet effluent criteria when DO was as low as 0.3 mg/L,and that nitrifier communities cultivated under low DO conditions had higher oxygen affinity than those cultivated under high DO conditions,as indicated by the oxygen half-saturation constant and nitrification ability. Based on nitrifier growth kinetics and on the oxygen mass transfer dynamic model（determined using different air flow rate（Q′air）and mixed liquor volatile suspended solids（MLVSS）values）,theoretical analysis indicated limited potential for energy saving by improving aeration diffuser performance when the activated sludge system had low oxygen consumption; however,operating at low DO and low MLVSS could significantly reduce energy consumption. Finally,a control strategy coupling sludge retention time and MLVSS to minimize the DO level was discussed,which is critical to appropriate setting of the oxygen point and to the operation of low DO treatment technology.

关键词： Aeration optimization Low dissolved oxygen nitrification Mixed liquor suspended solids Oxygen mass transfer Oxygen uptake rate

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Effects of Oxytetracycline on Methane Production and the Microbial communities During Anaerobic Digestion of Cow Manure

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Journal of Integrative Agriculture 2014年第6期13卷 1373-1381页

作者： KE Xin WANG Chun-yong LI Run-dong ZHANG Yun College of Energy and environment Shenyang Aerospace University College of Land and environment Shenyang Agriculture University

The effects of different concentrations of oxytetracycline （OTC） on the dynamics of bacterial and archaeal communities during the mesophilic anaerobic digestion （37＆#176;C） of cow manure were investigated. Before anaerobic digestion, OTC was added to digesters at concentrations of 20, 50, and 80 mg L-1, respectively. Compared with no-antibiotic control, all methane productions underwent different levels of inhibition at different concentrations of OTC. Changes in the bacterial and archaeal communities were discussed by using PCR-denaturing gradient gel electrophoresis （DGGE）. Results showed that OTC affected the richness and diversity of bacterial and archaeal communities. The bacterial genus Flavobacterium and an uncultured bacterium （JN256083.1） were detected throughout the entire process of anaerobic digestion and seemed to be the functional bacteria. Methanobrevibacter boviskoreani and an uncultured archaeon （FJ230982.1） dominated the archaeal communities during anaerobic digestion. These microorganisms may have high resistance to OTC and may play vital roles in methane production.

关键词： oxytetracycline anaerobic digestion stages (BDS DMS and FDS) PCR-DGGE bacterial community archaeal community

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