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Quantitative analysis of ruminal methanogenic microbial populations in beef cattle divergent in phenotypic residual feed intake(RFI)offered contrasting diets

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Journal of Animal Science and Biotechnology 2014年第4期5卷 439-447页

作者： Ciara A Carberry David A kenny alan k.k.lly Sinead M Waters Animal and Bioscience Research Department Animal and Grassland Research and Innovation CentreTeagascGrangeDunsanyCo.MeathIreland UCD School of Agriculture Food Science and Veterinary MedicineCollege of Life SciencesUniversity College DublinBelfieldDublin 4Ireland

Background：Methane（CH_4） emissions in cattle are an undesirable end product of rumen methanogenic fermentative activity as they are associated not only with negative environmental impacts but also with reduced host feed *** aim of this study was to quantify total and specific rumen microbial methanogenic populations in beef cattle divergently selected for residual feed intake（RFI） while offered（i） a low energy high forage（HF） diet followed by（ii） a high energy low forage（LF） *** fluid was collected from 14 high（H）and 14 low（L） RFI animals across both dietary *** real time PCR（qRT-PCR） analysis was conducted to quantify the abundance of total and specific rumen methanogenic *** correlation analysis was used to investigate the association between the relative abundance of methanogens and animal performance,rumen fermentation variables and diet ***：Abundance of methanogens,did not differ between RFI ***,relative abundance of total and specific methanogen species was affected（P〈 0.05） by diet type,with greater abundance observed while animals were offered the LF compared to the HF ***：These findings suggest that differences in abundance of specific rumen methanogen species may not contribute to variation in CH_4 emissions between efficient and inefficient animals,however dietary manipulation can influence the abundance of total and specific methanogen species.

关键词： Bovine qRT-PCR Residual feed intake Rumen methaongens

Advanced casting technologies for lightweight automotive applications

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China Foundry 2010年第4期7卷 463-469页

作者： alan A.Luo Anil k.Sachdev Bob R.Powell General Motors Global Research and Development Center

This paper provides an overview of alloy and process developments in aluminum and magnesium castings for lightweight automotive applications. Wear-resistant aluminum alloys, creep-resistant and high strength/ductility magnesium alloys have been developed for automotive applications. On the process front, vacuumassisted die casting and high vacuum die casting technologies have been developed for high-integrity body and chassis applications. Thin-wall and hollow casting components are being produced by low-pressure die casting processes for structural applications. Overcasting technology is gaining traction and has enabled mixed material designs for automotive sub-systems such as engine cradles and instrument panel beams. Simulation tools developed to predict the interfacial interactions of the dissimilar components and the structural integrity of the overcast systems are being validated in the casting trials.

关键词： lightweight aluminum alloy magnesium alloy die casting

Preparation and characterization of multimodal hybrid organic and inorganic nanocrystals of camptothecin and gold

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Acta Pharmaceutica Sinica B 2019年第1期9卷 128-134页

作者： Christin P. Hollis alan k. Dozier Barbara L. knutson Tonglei Li Department of Pharmaceutical Sciences University of Kentucky Electron Microscopy Center University of Kentucky Department of Chemical Engineering and Material Sciences University of Kentucky Department Industrial & Physical Pharmacy College of Pharmacy Purdue University

We demonstrate a novel inorganic-organic crystalline nanoconstruct, where gold atoms were imbedded in the crystal lattices as defects of camptothecin nanocrystals, suggesting its potential use as simultaneous agents for cancer therapy and bioimaging. The incorporation of gold, a potential computed tomography(CT) contrast agent, in the nanocrystals of camptothecin was detected by transmission electron microscope(TEM) and further quantified by energy dispersive X-ray spectrometry(EDS) and inductively coupled plasma-optical emission spectrometers(ICP-OES). Due to gold's high attenuation coefficient, only a relatively small amount needs to be present in order to create a good noise-to-contrast ratio in CT imaging. The imbedded gold atoms and clusters are expected to share the same biological fate as the camptothecin nanocrystals, reaching and accumulating in tumor site due to the enhanced permeation and retention(EPR) effect.

关键词： Hybrid inorganic-organic Drug delivery Camptothecin Gold nanoparticles Computed tomography(CT) contrast agent Cancer therapy and diagnosis

Gold modified cobalt-based Fischer-Tropsch catalysts for conversion of synthesis gas to liquid fuels

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Frontiers of Chemical Science and Engineering 2013年第3期7卷 262-269页

作者： alan J. Mccue Jura Aponaviciute Richard P.k. Wells James A. Anderson Surface Chemistry and Catalysis Group Department of Chemistry University of Aberdeen AB24 3UE Abcrdccn UK Surface Chemistry and Catalysis Group School of Engineering University of Aberdeen AB24 3UE Aberdeen UK

The addition of Au as a promoter/modifier for alumina supported Co catalyst has been studied by combined in-situ high temperature, high pressure Fourier transform infrared （FTIR） and on-line gas chromatography. The combination of these tools permitted the state of the active catalyst surface to be monitored while following the elution of reaction products during the first 5-7 h on stream of the catalyst. The catalysts under study were a 10%Co/ A1203 and a 2.5%Au/10%Co/A1203. Samples were characterised before use using Raman and temperature programmed reduction （TPR）. During the initial stages of reaction, hydrocarbons were built up on the surface of the catalyst as monitored by FTIR and the nature and amount of these species were assessed in terms of CH2/CH3 ratio and the density of these alkyl fragments by employing absorption coefficients for the individual components. The nature and reducibility of the Co particles were modified by the presence of Au while the later also shifted the CO/ H2 balance by acting as an effective water-gas shift catalyst during the early stages of reaction. This characteristic was lost during reaction as a consequence of redistribution of the two metallic phases.

关键词： gold modified catalyst conversion of synthesis gas

Egg-spot matching in common cuckoo parasitism of the oriental reed warbler: effects of host nest availability and egg rejection

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Chinese Birds 2016年第4期7卷 199-209页

作者： Donglai Li Yanan Ruan Ying Wang alan k.Chang Dongmei Wan Zhengwang Zhang Provincial key Laboratory of Animal Resource and Epidemic Disease Prevention College of Life Sciences Liaoning University Ministry of Education key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University

Background: The success of cuckoo parasitism is thought to depend largely on the extent of egg matching between cuckoo and host eggs, since poor-matching cuckoo egg would lead to more frequent egg rejection by the host. In this study, we investigated how egg-spot matching between the Common Cuckoo(Cuculus canorus) and its host, the Oriental Reed Warbler(Acrocephalus orientalis) is affected by the local parasitism rate, nest availability in breeding synchronization and egg ***: We used the paired design of parasitized and their nearest non-parasitized nests where breeding occurred simultaneously to compare egg-spot matching. The image analysis was used to compare four eggshell pattern variables, namely spot size, density, coverage on the different areas of egg surface, and the distribution on the whole egg surface. Egg recognition experiments were conducted to test the effect of egg spots on egg rejection by the ***: Our results show that much better matching in almost all spot parameters tested on the side of the egg and the spot distribution on the whole egg occurred in parasitized nests than in non-parasitized nests. Matching of spot density between cuckoo and host eggs in parasitized nests increased with the synchronization between temporal availability of nests and the egg-laying period of female cuckoos. Egg recognition experiments in which the warbler eggs were deliberately painted with extra spots led to a significantly higher egg rejection rate(78.3%) than of unpainted ***: Our data suggest that both the high temporal encounter rate between cuckoo and warbler nests as well as the high egg rejection ability of the host are important factors for egg-spot matching of the cuckoos.

关键词： Brood parasite Cuckoo Egg mimicry Egg matching Spot pattern Egg rejection Parasitism rate Oriental Reed Warbler

Geographic variation in growth and phenology of two dominant central US grasses:consequences for climate change

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Journal of Plant Ecology 2014年第3期7卷 211-221页

作者： Amanda L.Giuliani Eugene F.kelly alan k.knapp Department of Biology Colorado State UniversityFort CollinsCO 80523USA Department of Soils and Crops Science Colorado State UniversityFort CollinsCO 80523USA Graduate Degree Program in Ecology and Department of Biology Colorado State UniversityFort CollinsCO 80523USA

Aims The rate of climate change may exceed many plant species’migration rates,particularly for long-lived perennial species that dominate most *** bioclimatic envelopes shift more rapidly than dominant species can migrate,individuals located peripheral to biomes or in adjacent biomes may become a significant source of traits for future dominant populations(DPs).Thus,traits of individuals from peripheral populations(PPs)may affect future ecosystem functioning more than those of today’s *** We assessed key traits of individuals collected from populations that currently dominate two central US grasslands,the shortgrass steppe(Bouteloua gracilis)and the tallgrass prairie(Andropogon gerardii).We compared these to individuals from PPs in a reciprocal-transplant common garden experiment with gardens at the Shortgrass Steppe Long Term Ecological Research site in Colorado and the konza Prairie Biological Station Long Term Ecological Research site in *** and PPs were subjected to high and reduced water availability in common gardens located in each *** measured included the following:individual plant biomass,reproductive allocation,specific leaf area(SLA)and plant–water *** focused on the climate-change relevant comparisons of traits from PPs versus DPs expressed under the climate of *** Findings PPs of *** differed from DPs primarily in phenological *** a semiarid shortgrass steppe climate,PPs initiated flowering later in the season,produced fewer reproductive tillers and were more sensitive to water *** differences between populations were *** ***,biomass in PPs was 50%lower than in DPs under the mesic tallgrass prairie climate and reproductive tillers were considerably smaller,despite higher SLA in *** of PPs was less sensitive to water stress,*** these results,we conclude that key traits of PPs differed from DPs in both grassland types,but potential effects on r

关键词： grassland phenology productivity traits water stress

Human action recognition using a time-delayed photonic reservoir computing

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Science China(Information Sciences) 2023年第11期66卷 309-310页

作者： Chao kAI Pu LI Yi YANG Bingjie WANG k.alan SHORE Yuncai WANG key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Guangdong Provincial key Laboratory of Photonics Information Technology School of Information Engineering 3. School of Computer Science and Electronic Engineering Bangor University

Human action recognition(HAR) has important applications, including video retrieval, entertainment, autonomous navigation systems, and visual surveillance systems [1]. Unfortunately, accurate and efficient HAR remains a challenging task in the field of computer vision because its modeling and characteristic representation belong to threedimensional space-time instead of common two-dimensional space [2].

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Integrated morphological,CO1 and distributional analysis confirms many species in the Iridomyrmex anceps(Roger)complex of ants

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Zoological Systematics 2020年第3期45卷 219-230页

作者： alan N.Andersen Benjamin D.Hoffmann Stefanie k.Oberprieler Research Institute for the Environment and Livelihoods Charles Darwin UniversityDarwinNT 0909Australia CSIRO Tropical Ecosystems Research Centre PMB 44 WinnellieNT 0822DarwinAustralia

Iridomyrmex Mayr is Australia’s most ecologically dominant ant genus and has been estimated to contain at least 350 ***,a recent taxonomic revision of the genus recognized only 79 *** contrasting views have major implications for an understanding of not only the diversity of such an important genus,but also its biogeography and evolutionary *** taxonomic revision considered ***(Roger)to represent a single species,despite its marked morphological variation and range from Australia to India and ***,a preliminary morphological analysis recognized six species within the *** we describe results from an integrated morphological,CO1 and distributional analysis that assesses if the six morphologically based taxa are differentiated genetically,and if there are additional species in the complex that are yet to be *** found the morphological differentiation within the complex to be matched by extensive genetic divergence,and that matched morphological and genetic differentiation frequently occurs in *** recognize up to 18 species among our sequenced specimens from the complex,with their centre of diversity occurring in *** findings are consistent with results showing that other Iridomyrmex species recognized in the taxonomic revision represent several to many actual *** recognition of only 79 species of Iridomyrmex does not reflect true diversity within this ecologically dominant genus,nor the complexity of its biogeography and evolutionary history.

关键词： Australia cryptic species Indo-Pacific South-East Asia unrecognized diversity

The influence of chemical composition on models of Type Ia supernovae

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Frontiers of physics 2013年第2期8卷 168-188页

作者： alan C. Calder Brendan k. krueger Aaron P. Jackson Dean M. Townsley Department of Physics Astronomy The State University of New York - Stony Brook Stony BrookUSA NY 11794 New York Center for Computational Sciences The State University of New York - Stony Brook Stony BrookUSA NY 11794 National Research Council Research Associateship Program and Laboratories for Computational Physics and Fluid Dynamics Naval Research Laboratory WashingtonUSA DC 20375 Department of Physics and Astronomy The University of Alabama TuscaloosaUSA AL 35487

Type Ia supernovae are bright stellar explosions distinguished by standardizable light curves that allow for their use as distance indicators for cosmological studies. Despite the highly successful use of these events in this capacity, many fundamental questions remain. Contemporary research inves- tigates how properties of the progenitor system that follow from the host galaxy such as composition and age influence the brightness of an event with the goal of better understanding and assessing the intrinsic scatter in the brightness. We provide an overview of these supernovae and proposed progenitor systems, all of which involve one or more compact stars known as white dwarfs. We describe contemporary research investigating how the composition and structure of the progenitor white dwarf systematically influences the explosion outcome assuming the progenitor is a single white dwarf that has gained mass from a companion. We present results illustrating some of these systematic effects from our research.

关键词： hydrodynamics nuclear reactions nucleosynthesis abundances stars: supernovae:general stars: white dwarfs