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Progress in ileal endogenous amino acid flow research in poultry

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Journal of Animal Science and Biotechnology 2021年第2期12卷 415-425页

作者： V.Ravindran Monogastric Research centre School of Agriculture and EnvironmentMassey UniversityPalmerston North 4442New Zealand

The progress in our understanding of the endogenous protein concept over the past century is *** proteins found in the digesta at the terminal ileum of poultry,known as endogenous protein loss,are comprised of digestive secretions,mucus and sloughed gut epithelial *** measurement of this loss is of fundamental importance because it is an indicator of gut metabolism and is essential to adjust apparent estimates of ileal amino acid *** ileal endogenous amino acid losses comprise of two components,namely basal and specific *** basal losses are fixed and associated with feed dry matter intake,whereas the specific losses are variable and induced by the presence of dietary components such as fibre and *** there is no methodology available to directly measure the specific endogenous losses and these losses are calculated by determining the basal and total(basal plus specific)losses and,then subtracting the basal losses from total *** seminal features,specific applications and shortcomings of available methodologies are briefly outlined as well as the practical challenges faced in using the published endogenous amino acid loss values for true digestibility *** relevance of taurine as a component of endogenous protein flow in poultry is identified for the first time.

关键词： Basal loss Digestible amino acids Endogenous amino acid losses Poultry Specific loss

Computational modeling of free-surface slurry flow problems using particle simulation method

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Journal of Central South University 2013年第6期20卷 1653-1660页

作者：赵崇斌彭省临刘亮明 B.E.Hobbs A.Ord Computational Geosciences Research centre Central South University School of Earth and environment The University of Western Australia

The particle simulation method is used to solve free-surface slurry flow problems that may be encountered in several scientific and engineering *** main idea behind the use of the particle simulation method is to treat granular or other materials as an assembly of many *** with the continuum-mechanics-based numerical methods such as the finite element and finite volume methods,the movement of each particle is accurately described in the particle simulation method so that the free surface of a slurry flow problem can be automatically *** major advantage of using the particle simulation method is that only a simple numerical algorithm is needed to solve the governing equation of a particle simulation *** the purpose of illustrating how to use the particle simulation method to solve free-surface flow problems,three examples involving slurry flow on three different types of river beds have been *** related particle simulation results obtained from these three examples have demonstrated that:1) The particle simulation method is a promising and useful method for solving free-surface flow problems encountered in both the scientific and engineering fields;2) The shape and irregular roughness of a river bed can have a significant effect on the free surface morphologies of slurry flow when it passes through the river bed.

关键词： particle simulation free surface slurry flow numerical method

Recent progress in polar metabolite quantification in plants using liquid chromatography-mass spectrometry

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Journal of Integrative Plant Biology 2014年第9期56卷 816-825页

作者： Zhiqian Liu Simone Rochfort Department of environment and Primary Industries Dairy Futures Co-operative Research centre La Trobe University

Metabolite analysis or metabolomics is an important component of systems biology in the post-genomic *** separate liquid chromatography（LC） methods for quantification of the major classes of polar metabolites of plants have been available for decades,a single method that enables simultaneous determination of hundreds of polar metabolites is possible only with gas chromatography-mass spectrometry（GC-MS） *** rapid expansion of new LC stationary phases in the market and the ready access of mass spectrometry in many laboratories provides an excellent opportunity for developing LC-MS based methods for multitarget quantification of polar *** various LC-MS methods have been developed over the last 10 years with the aim to quantify one or more classes of polar compounds in different matrices,currently there is no consensus LC-MS method that is widely used in plant metabolomics *** most promising methods applicable to plant metabolite analysis will be reviewed in this paper and the major problems encountered *** aim of this review is to provide plant scientists,with limited to moderate experience in analytical chemistry,with up-to-date and simplified information regarding the current status of polar metabolite analysis using LC-MS techniques.

关键词： Aqueous normal phase chromatography hydrophilic interaction liquid chromatography liquid chromatography-mass spectrometry plants polar metabolites

Petroleum substitution, greenhouse gas emissions reduction and environmental benefits from the development of natural gas vehicles in China

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Petroleum Science 2018年第3期15卷 644-656页

作者： Jie-Hui Yuan Sheng Zhou Tian-Duo Peng Ge-Hua Wang Xun-Min Ou Institute of Energy Environment and Economy Tsinghua University China Automotive Energy Research centre Tsinghua University

This study develops a bottom-up model to quantitatively assess the comprehensive effects of replacing traditional petroleum-powered vehicles with natural gas vehicles（NGVs） in China based on an investigation of the direct energy consumption and critical air pollutant（CAP） emission intensity, life-cycle energy use and greenhouse gas（GHG） emission intensity of NGV fleets. The results indicate that, on average, there are no net energy savings from replacing a traditional fuel vehicle with an NGV. Interestingly, an NGV results in significant reductions in direct CAP and life-cycle GHG emissions compared to those of a traditional fuel vehicle, ranging from 61% to 76% and 12% to 29%, respectively. Due to the increasing use of natural gas as a vehicle fuel in China（i.e. approximately 28.2 billion cubic metres of natural gas in2015）, the total petroleum substituted with natural gas was approximately 23.8 million tonnes（Mt）, which generated a GHG emission reduction of 16.9 Mt of CO2 equivalent and a CAP emission reduction of 1.8 Mt in 2015. Given the significant contribution of NGVs, growing the NGV population in 2020 will further increase the petroleum substitution benefits and CAP and GHG emission reduction benefits by approximately 42.5 Mt of petroleum-based fuel, 3.1 Mt of CAPs and 28.0 Mt of GHGs. By 2030, these benefits will reach 81.5 Mt of traditional petroleum fuel, 5.6 Mt of CAPs and 50.5 Mt of GHGs, respectively.

关键词： Natural gas vehicles Energy use Greenhouse gases Critical air pollutants China Life-cycle analysis

A spatial model for the assessment of debris flow susceptibility along the Kodaikkanal-Palani traffic corridor

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Frontiers of Earth Science 2020年第2期14卷 326-343页

作者： Evangelin Ramani SUJATHA centre for Advanced Research on environment School of Civil EngineeringSASTRA Deemed UniversityThanjavur 613401India

Debris flow is one of the most destructive water related mass movements that affects the development of mountain terrains.A reliable assessment of debris flow susceptibility requires adequate data,but in most developing countries like India,there is a dearth of such extensive scientific *** study presents a novel approach for assessing debris flow using the analytical network process(ANP)in data insufficient regions.A stretch of hill road between Kumburvayal and Vadakaunchi along the Kodaikkanal-Palani Traffic Corridor(M171)was considered for this *** significant factors including the nature of slope forming materials,hydraulic conductivity,slope,vegetation,and drainage density were identified from intense field surveys and inspections in order to assess the susceptibility of the terrain to debris *** model endorsed the interdependencies between the selected *** resulting debris flow susceptibility map delineated regions highly prone to debris flow occurrences,which constituted nearly 23%of the selected road stretch.

关键词： analytical network process(ANP) debris flow hydraulic conductivity GIS Kodaikkanal infinite slope stability model steady state hydrologic model

How to assess the success of the open data ecosystem?

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International Journal of Digital Earth 2017年第3期10卷 284-306页

作者： Frederika Welle Donker Bastiaan van Loenen Faculty of Architecture and the Built environment Knowledge Centre GeoInformation GovernanceDelft University of TechnologyDelftThe Netherlands

Open data are currently a hot topic and are associated with realising ambitions such as a more transparent and efficient government,solving societal problems,and increasing economic *** describe and monitor the state of open data in countries and organisations,several open data assessment frameworks were *** high scores in these assessment frameworks,the actual(re)use of open government data(OGD)fails to live up to its *** review of existing open data assessment frameworks reveals that these only cover parts of the open data *** have developed a framework,which assesses open data supply,open data governance,and open data user characteristics *** holistic open data framework assesses the maturity of the open data ecosystem and proves to be a useful tool to indicate which aspects of the open data ecosystem are successful and which aspects require *** initial assessment in the Netherlands indicates that the traditional geographical data perform significantly better than non-geographical data,such as healthcare ***,open geographical data policies in the Netherlands may provide useful cues for other OGD strategies.

关键词： Open data geodata assessment framework open data governance open data maturity

Rates and processes affecting As speciation and mobility in lake sediments during aging

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Journal of environmental Sciences 2018年第4期30卷 338-347页

作者： Alan Lock Dirk Wallschlager Nelson Belzile Graeme Spiers Celine Gueguen environmental and Life Sciences Graduate Program Trent University School of the environment Department of Chemistry and Water Quality CentreTrent University Department of Chemistry Laurentian University School of the environment Departments of Earth Sciences and BiologyLaurentian University School of the environment and Chemistry Department Trent University

Sediments from an arsenic（As） contaminated groundwater vent site were used to investigate As（ Ⅲ） binding, transformation and redistribution in native and iron oxide amended lake sediments using aging spiked batch reactions and a sequential extraction procedure that maintains As（V） and As（ Ⅲ） speciation. In the native sediments, fractionation analysis revealed that 10% of the spiked As（ Ⅲ） remained intact after a 32-day aging experiment and was predominantly adsorbed to the strongly sorbed（NH4H2PO4 extractable） and amorphous Fe oxide bound（H3PO4 extractable） fractions. Kinetic modelling of the experimental results allowed identifying the dominant reaction path for depletion of dissolved As（ Ⅲ） to As（ Ⅲ）absorbed on to the solid phase, followed by oxidation in the solid phase. Arsenite was initially adsorbed primarily to the easily exchangeable fraction（（NH4）2SO4 extractable）, then rapidly transformed into As（V） and redistributed to the strongly sorbed and amorphous Fe oxide bound fractions. Oxidation of As（ Ⅲ） in recalcitrant fractions was less efficient. The iron oxide amendments illustrated the controls that iron oxides can have on As（ Ⅲ） binding and transformation rates. In goethite amended samples As（ Ⅲ） oxidation was faster and primarily occurred in the strongly sorbed and amorphous Fe oxide bound fractions. In these samples,19.3 μg Mn was redistributed（compared to the native sediment） from the easily exchangeable and crystalline Fe oxide bound fractions to the strongly sorbed and amorphous Fe oxide bound fractions, indicating that goethite may act as a catalyst for Mn（Ⅱ） oxidation, thereby producing sorbed Mn（ Ⅲ/Ⅳ ）, which then appears to be involved in rapidly oxidizing As（ Ⅲ）.

关键词： Arsenite Oxidation Fractionation Redistribution Modelling

Assessing the maturity of China's seven carbon trading pilots

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Advances in Climate Change Research 2019年第3期10卷 150-157页

作者： LIU Zhe ZHANG Yong-Xiang Policy Research centre for environment and Economy Ministry o f Ecology and EnvironmentBeijing100029China National Climate Center China Meteorological AdministrationBeijing100081China

Indicators based on the developed version of the Capability Maturity Model were set up to access the maturity degree of China's seven pilot carbon markets from 2013 to 2017. Results show that the maturity degree of Shenzhen and Beijing pilot carbon markets ranks first;while those of Guangdong, Hubei, and Shanghai rank second. Tianjin and Chongqing rank lowest. Most of pilot markets failed to perform well on price efficiency except Shenzhen. There is significant disparity in the scores that the pilot carbon markets got, with a range from 9 to 73. The drivers to maintain market maturity is different among the pilot markets, either with a good performance on market structure, scale, or efficiency could lead to a certain score. Much could be done to increase the maturity level of the carbon market. Further downscaling the firm size, raising the legislation level, and increasing the participation of the third party entities may help the carbon market to grow healthier.

关键词： China Carbon market pilots Maturity assessment Market structure Market scale Market efficiency

Which are the most favourable conditions for reducing soil CO_(2)emissions with no-tillage?Results from a meta-analysis

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International Soil and Water Conservation Research 2022年第3期10卷 497-506页

作者： Simone Bregaglio Gabriele Mongiano Rossana M.Ferrara Fabrizio Ginaldi Alessandra Lagomarsino Gianfranco Rana CREA-Council for Agricultural Research and Economics Research Centre for Agriculture and EnvironmentI-40128BolognaItaly CREA-Council for Agricultural Research and Economics Research Centre for Plant Protection and CertificationSS 11 km 2500I-13100VercelliItaly CREA-Council for Agricultural Research and Economics Research Centre for Agriculture and EnvironmentI-70125BariItaly CREA-Council for Agricultural Research and Economics Research Centre for Agriculture and EnvironmentI-50125FirenzeItaly

No-tillage practices have a recognised beneficial impact on soil and water conservation while reducing erosion processes and enhancing soil organic matter ***,scientists continue to debate the effectiveness of no-tillage in reducing soil carbon dioxide(CO_(2))emissions from *** the same line of inquiry pursued by the authors who reviewed the impact of conservative practices on direct CO_(2)emissions,we applied meta-analytic and machine learning techniques to unravel the effect of no-tillage under contrasting pedo-environmental conditions and agricultural *** analysed fifty-six experimental studies investigating direct soil CO_(2)emissions from no-tillage and conventional tillage practices(102 paired observations),considering pedological(soil texture,soil organic carbon content),environmental(climate type),and management(crop rotation,experiment duration)*** estimated the effect of different practices on the daily amount of soil CO_(2)emissions,and the impact of tillage in the period immediately following the *** main insights of this study are:(i)the conditions leading to the highest reduction of CO_(2)emissions due to no-tillage were long-term experiments(standardised mean differenceβ=0.64)conducted in arid environments(β=0.76)and clay soils(β=0.81),with low organic carbon content(β=0.79)where crop rotations(β=0.65)were performed;(ii)the same conditions were associated with the lowest absolute CO_(2)emissions,irrespective of soil management;(iii)the highest contribution to the variability of absolute soil CO_(2)emissions was associated with soil texture(mean decrease in accuracy of Random Forest models,MDA=4.57),rotation(MDA=3.07),experiment duration(MDA=2.93)and soil organic carbon content(MDA=2.24),rather than to tillage practices;(iv)soil CO_(2)emissions almost doubled in the first day after a tillage event,consistently across studies(p=0.001).This meta-analysis offers quantitative figures on the impact of tillage

关键词： Agricultural soils Greenhouse gases Global warming Net-zero agriculture