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Pedosphere 2016年第2期26卷 192-205页

作者： Francisco J. CALDERON David NIELSEN Veronica ACOSTA-MARTINEZ Merle F. VIGIL Drew LYON USDA-ARS Central Great Plains Research Station Akron CO 80720 USA USDA-ARS Cropping Systems Research Laboratory Wind Erosion and Water Conservation Unit Lubbock TX 79415 USA Department of Crop and Soil Sciences Washington State University Pullman WA 99164-6420 USA

盖子庄稼能由增加碳(C) 供应在土壤微生物学上有有益的效果，但是这些有益的效果能被降水条件调制。这研究的目的是比较休闲冬季小麦(Triticum aestivum L.) 旋转到在在半干旱的美国高平原的 rainfed 和灌溉条件下面的几盖子庄稼冬季小... 详细信息

盖子庄稼能由增加碳(C) 供应在土壤微生物学上有有益的效果，但是这些有益的效果能被降水条件调制。这研究的目的是比较休闲冬季小麦(Triticum aestivum L.) 旋转到在在半干旱的美国高平原的 rainfed 和灌溉条件下面的几盖子庄稼冬季小麦旋转。实验在科罗拉多在二个地点，在内布拉斯加的 Sidney，和 Akron 被执行，美国与三次在在盖子庄稼结束的 2012-2013 的土壤采样，种的小麦，和小麦成熟。实验包括了四单个种类的盖子庄稼， 10 种类混合物，和一个休闲处理。测量的变量是土壤 C 和氮(N) ，由甲基酉旨(名声) 介绍的丰满的酸的土壤社区结构，和土壤 -glucosidase,-glucosaminidase, 和 phosphodiesterase 活动。休闲处理，缺乏生活植物，在盖子庄稼结束减少了大多数名声的集中。全部的名声集中与盖子庄稼生物资源被相关(R = 0.62 在 Sidney 并且 0.44 在 Akron ) 。等到种的小麦，有灌溉的有益的效果，它在 mycorrhizal 和原生动物门标记引起了增加。在小麦成熟，土壤名声上的盖子庄稼和灌溉效果减退了，但是灌溉在 Akron 在 -glucosidase 和 phosphodiesterase 活动上有积极效果，它二个地点中是更干燥的。盖子庄稼和灌溉是慢的影响土壤 C 集中。我们的结果证明盖子庄稼在在半干旱的基于小麦的旋转和灌溉的微生物引起的社区能提高的土壤上有短命效果土壤酶活动。在半干旱的环境，更长的时间跨度可能被需要在土壤上看见盖子庄稼的有益的效果微生物引起的社区结构，土壤酶活动，和土壤 C 隐遁。

关键词：土壤微生物群落覆盖作物灌溉条件酯酶活性美国平原 β-葡萄糖苷酶微生物群落结构

Amino acid digestibility in low-fat distillers dried grains with solubles fed to growing pigs

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Journal of Animal Science and Biotechnology 2014年第4期5卷 414-420页

作者： Shelby Marie Curry Diego Mario david Labadan Navarro Ferdinando nielsen Almeida Juliana Abranches Soares Almeida Hans Henrik Stein Department of Animal Sciences University of Illinois

The objective of this experiment was to determine the standardized ileal digestibility（SID） of amino acids（AA） in 3sources of distillers dried grains with solubles（DDGS） with different concentrations of fat.Twelve growing barrows（initial body weight：76.1 ± 6.2 kg） were randomly allotted to a replicated 6×4 Youden square design with 6 diets and 4 periods.The fat content of the 3 sources of DDGS were 11.5,7.5,and 6.9%respectively.Diets contained 60%DDGS and fat concentration of the diets were 7.5,52,and 5.2%,respectively.Two additional diets containing the 2sources of DDGS with 75 and 6.9%fat were also formulated,and corn oil was added to these diets to increase the concentration of fat in the diets to levels that were calculated to be similar to the diet containing conventional DDGS with 11.5%fat.A N-free diet was also formulated to calculate endogenous losses of crude protein（CP） and AA from the pigs.Pigs were fed experimental diets during four 7-d periods.The first 5 d of each period were an adaptation period and ileal digesta were collected on d 6 and 7 of each period.The apparent ileal digestibililty（AID） and SID of CP and all indispensable AA,except AID Pro and SID of Trp,were greater（P 〈 0.01） in conventional DDGS than in the 2 sources of DDGS with reduced fat.Adding oil to the diets containing the 2 sources of DDGS with reduced fat did not consistently increase SID of AA.In conclusion,conventional DDGS has greater SID values for most AA compared with DDGS that contains less fat and inclusion of additional oil to diets containing low-fat DDGS does not increase AID or SID of AA.The lower AA digestibility in low-fat DDGS could not be overcome by the inclusion of additional fat to the diets.

关键词： Amino acid digestibility Distillers dried grains with solubles Pigs

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通过诱变选育低去甲基烟碱深色晾烟品系

中国烟草科学 2009年第1期30卷 49-49页

作者： Yanxin SHEN Dongmei Xu david Norman Mark nielsen 任民(译) 美国无烟烟草公司(USSTC) 温切斯特美国肯塔基州40391 不详

目前已经分离到两个在烟草去甲基烟碱形成过程中起作用的基因。阻断这两个基因可使烟草植株中的去甲基烟碱含量较低，从而使得一种在烟叶调制过程中经亚硝化形成的TSNA—N′-亚硝基去甲基烟碱（NNN）的含量降低。我们通过乙基甲烷磺酸盐... 详细信息

目前已经分离到两个在烟草去甲基烟碱形成过程中起作用的基因。阻断这两个基因可使烟草植株中的去甲基烟碱含量较低，从而使得一种在烟叶调制过程中经亚硝化形成的TSNA—N′-亚硝基去甲基烟碱（NNN）的含量降低。我们通过乙基甲烷磺酸盐（EMS）处理创造了一个深色晾烟的孟德尔遗传近等基因系突变群体。本研究中，我们报道了一个新的深色烟多突变体的发现，这一突变体能够消除主效和微效脱甲基酶的活性。第一代突变群体在大田环境下种植，第二代突变群体在大田和温室两种环境下种植。

关键词：烟碱含量深色诱变选育近等基因系品系烟草植株孟德尔遗传甲烷磺酸盐

烟碱去甲基化酶基因功能阻断是一种有效和实用的降低烟草去甲基烟碱水平的方法

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中国烟草科学 2009年第1期30卷 67-67页

作者： david Norman Marcos Lusso Greg Davis Frank Hart Mark nielsen 任民美国无烟烟草公司(USSTC) 温切斯特美国肯塔基州40391

阻断烟草中去甲基烟碱的形成可以降低一种在烟叶调制过程中经亚硝化形成的TSNA——N’-亚硝基-去甲基烟碱（NNN）的含量。在之前的研究中，我们报道了烟碱去甲基化酶基因的发现及其使用GMO（转基因生物，RNAi干扰方法）和非GMO（诱变）... 详细信息

阻断烟草中去甲基烟碱的形成可以降低一种在烟叶调制过程中经亚硝化形成的TSNA——N’-亚硝基-去甲基烟碱（NNN）的含量。在之前的研究中，我们报道了烟碱去甲基化酶基因的发现及其使用GMO（转基因生物，RNAi干扰方法）和非GMO（诱变）策略降低烟碱去甲基酶活性。本研究报道了在高代和育成品系中这种策略的有效性和稳定性，并且描述了将RNAi和突变位点成功转入不同品种的育种过程和进展。在多重试验中实验材料种植在大田环境下，包括4代RNAi转基因系和相应的R2代雄性不育系副本。

关键词：烟碱基因功能甲基化酶烟草碱水 RNAi 转基因生物雄性不育系

Towards a standard diet-induced and biopsy-confirmed mouse model of non-alcoholic steatohepatitis: Impact of dietary fat source

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World Journal of Gastroenterology 2019年第33期25卷 4904-4920页

作者： Michelle L Boland Denise Oro Kirstine S T■lb■l Sebastian T Thrane Jens Christian nielsen Taylor S Cohen david E Tabor Fiona Fernandes Andrey Tovchigrechko Sanne S Veidal Paul Warrener Bret R Sellman Jacob Jelsing Michael Feigh Niels Vrang James L Trevaskis Henrik H Hansen Cardiovascular Renal and Metabolic DiseasesMedImmuneGaithersburgMD 20878United States Pharmacology GubraH■rsholm DK-2970Denmark

BACKGROUND The trans-fat containing AMLN(amylin liver non-alcoholic steatohepatitis,NASH)diet has been extensively validated in C57BL/6J mice with or without the Lep^ob/Lep^ob(ob/ob)mutation in the leptin gene for reliably inducing metabolic and liver histopathological changes recapitulating hallmarks of NASH.Due to a recent ban on trans-fats as food additive,there is a marked need for developing a new diet capable of promoting a compatible level of disease in ob/ob and C57BL/6J mice.AIM To develop a biopsy-confirmed mouse model of NASH based on an obesogenic diet with trans-fat substituted by saturated fat.METHODS Male ob/ob mice were fed AMLN diet or a modified AMLN diet with trans-fat(Primex shortening)substituted by equivalent amounts of palm oil[Gubra amylin NASH,(GAN)diet]for 8,12 and 16 wk.C57BL/6J mice were fed the same diets for 28 wk.AMLN and GAN diets had similar caloric content(40%fat kcal),fructose(22%)and cholesterol(2%)level.RESULTS The GAN diet was more obesogenic compared to the AMLN diet and impaired glucose tolerance.Biopsy-confirmed steatosis,lobular inflammation,hepatocyte ballooning,fibrotic liver lesions and hepatic transcriptome changes were similar in ob/ob mice fed the GAN or AMLN diet.C57BL/6J mice developed a mild to moderate fibrotic NASH phenotype when fed the same diets.CONCLUSION Substitution of Primex with palm oil promotes a similar phenotype of biopsyconfirmed NASH in ob/ob and C57BL/6J mice,making GAN diet-induced obese mouse models suitable for characterizing novel NASH treatments.

关键词： Non-alcoholic steatohepatitis High-fat diet Mouse model Histopathology Fibrosis Liver biopsy Liver transcriptome

The functional properties of synapses made by regenerated axons across spinal cord lesion sites in lamprey

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Neural Regeneration Research 2022年第10期17卷 2272-2277页

作者： david Parker Department of Physiology Developmentand NeuroscienceUniversity of CambridgeCambridgeUK

While the anatomical properties of regenerated axons across spinal cord lesion sites have been studied extensively,little is known of how the functional properties of regenerated synapses compared to those in unlesioned animals.This study aims to compare the properties of synapses made by regenerated axons with unlesioned axons using the lamprey,a model system for spinal injury research,in which functional locomotor recovery after spinal cord lesions is associated with axonal regeneration across the lesion site.Regenerated synapses below the lesion site did not differ from synapses from unlesioned axons with respect to the amplitude and duration of single excitatory postsynaptic potentials.They also showed the same activity-dependent depression over spike trains.However,regenerated synapses did differ from unlesioned synapses as the estimated number of synaptic vesicles was greater and there was evidence for increased postsynaptic quantal amplitude.For axons above the lesion site,the amplitude and duration of single synaptic inputs also did not differ significantly from unlesioned animals.However,in this case,there was evidence of a reduction in release probability and inputs facilitated rather than depressed over spike trains.Synaptic inputs from single regenerated axons below the lesion site thus do not increase in amplitude to compensate for the reduced number of descending axons after functional recovery.However,the postsynaptic input was maintained at the unlesioned level using different synaptic properties.Conversely,the facilitation from the same initial amplitude above the lesion site made the synaptic input over spike trains functionally stronger.This may help to increase propriospinal activity across the lesion site to compensate for the lesion-induced reduction in supraspinal inputs.The animal experiments were approved by the Animal Ethics Committee of Cambridge University.

关键词： electrophysiology lamprey plasticity regeneration reticulospinal axon spinal cord spinal injury synapse

Programmable polyketide biosynthesis platform for production of aromatic compounds in yeast

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Synthetic and Systems Biotechnology 2020年第1期5卷 11-18页

作者： Tadas Jakočiūnas Andreas K.Klitgaard Eftychia Eva Kontou Julie Bang nielsen Emil Thomsen david Romero-Suarez Kai Blin Christopher J.Petzold Jennifer W.Gin Yaojun Tong Charlotte Held Gotfredsen Pep Charusanti Rasmus J.N.Frandsen Tilmann Weber Sang Yup Lee Michael K.Jensen Jay D.Keasling The Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKgs.LyngbyDenmark Joint BioEnergy Institute EmeryvilleCAUSA Biological Systems&Engineering Division Lawrence Berkeley National LaboratoryBerkeleyCAUSA Department of Chemical and Biomolecular Engineering&Department of Bioengineering University of California BerkeleyCAUSA Center for Synthetic Biochemistry Institute for Synthetic BiologyShenzhen Institutes for Advanced TechnologiesShenzhenChina Department of Chemistry Technical University of DenmarkKgs.LyngbyDenmark Department of Biotechnology and Biomedicine Technical University of DenmarkKgs.LyngbyDenmark Department of Chemical and Biomolecular Engineering(BK21 Plus Program) Korea Advanced Institute of Science and Technology(KAIST)291 Daehak-roYuseong-guDaejeon34141Republic of Korea

To accelerate the shift to bio-based production and overcome complicated functional implementation of natural and artificial biosynthetic pathways to industry relevant organisms,development of new,versatile,bio-based production platforms is required.Here we present a novel yeast-based platform for biosynthesis of bacterial aromatic polyketides.The platform is based on a synthetic polyketide synthase system enabling a first demonstration of bacterial aromatic polyketide biosynthesis in a eukaryotic host.

关键词： Natural products Synthetic biology Aromatic polyketides CRISPR/Cas9 Polyketide Production platform in eukaryotes Metabolic engineering Biotechnology

Increasing our return on investment in science:Start with better behavior

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Journal of Sport and Health Science 2023年第3期12卷 281-283页

作者： david Moher Centre for Journalology Clinical Epidemiology programOttawa Hospital Research InstituteOttawaON K1H 8L6Canada School of Epidemiology and Public HealthUniversity of OttawaOttawaON K1H 8L6Canada

In August of 2022,I gave the opening keynote address at the 5th North American Congress on Biomechanics,in Ottawa,Canada.The topic of my talk was about whether the research ecosystem was getting a reasonable return on... 详细信息

关键词： return Canada investment

Feeding Biochar to Cows:An Innovative Solution for Improving Soil Fertility and Farm Productivity

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Pedosphere 2015年第5期25卷 666-679页

作者： Stephen JOSEPH Doug POW Kathy DAWSON david R.G.MITCHELL Aditya RAWAL James HOOK Sarasadat TAHERYMOOSAVI Lukas VAN ZWIETEN Joshua RUST Scott DONNE Paul MUNROE Ben PACE Ellen GRABER Torsten THOMAS Shaun nielsen Jun YE Yun LIN PAN Genxing LI Lianqing Zakaria M.SOLAIMAN Discipline of Chemistry University of Newcastle School of Materials Science and Engineering University of New South Wales Electron Microscopy Center AIIMUniversity of Wollongong Institute of Resources Ecosystem and Environment of AgricultureNanjing Agricultural University Marron Brook Farm Warren Catchments Council 52 Bath StManjimup 6258 (Australia) Mark Wainwright Analytical Centre University of New South Wales Wollongbar Primary Industries Institute NSW Department of Primary Industries Institute of Soil Water and Environmental SciencesThe Volcani CenterAgricultural Research Organization Centre for Marine Bio-Innovation School of Biotechnology and Biomolecular SciencesThe University of New South Wales Soil Biology and Molecular Ecology Group School of Earth and Environment (M087)The University of Western Australia

Addition of biochar produced through thermal decomposition of biomass has been seen as a strategy to improve soils and to sequester carbon(C), but wide scale implementation of the technology requires to devise innovative profitable solutions. To develop biochar utilisation with an integrated system approach, an innovative program was implemented in 2012 on a 53-ha farm in Western Australia to determine the costs and benefits of integrating biochar with animal husbandry and improvement of pastures. Biochar was mixed with molasses and fed directly to cows. The dung-biochar mixture was incorporated into the soil profile by dung beetles.We studied the changes in soil properties over 3 years. Biochar extracted from fresh dung and from the soil to a depth of 40 cm was characterised. A preliminary financial analysis of the costs and benefits of this integrated approach was also undertaken. The preliminary investigation results suggested that this strategy was effective in improving soil properties and increasing returns to the farmer. It was also concluded that the biochar adsorbed nutrients from the cow's gut and from the dung. Dung beetles could transport this nutrient-rich biochar into the soil profile. There was little evidence that the recalcitrant component of the biochar was reduced through reactions inside the gut or on/in the soil. Further research is required to quantify the long-term impact of integrating biochar and dung beetles into the rearing of cows.

关键词：土壤肥力生物炭农业生产率创新喂牛土壤性质新鲜粪便生物利用

Natural products and drug discovery

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National Science Review 2022年第11期9卷 37-57页

作者： david J.Newman NIH Special Volunteer

This review covers the recent history of a series of very important natural products and their derivatives that are currently in use or under evaluation in the areas of anti-infectives, important cancer treatments that include antibody drug conjugates, followed by a discussion of type 2 diabetes(T2DM) drugs and angiotensin converting enzyme inhibitors. The current structures of the agents are shown, though in the case of some peptides used in T2DM drugs the standard single leTher abbreviation for an amino acid is used.

关键词： artemisinin glycopeptides anthracyclines dolastatin diabetes 2 ACE inhibitors