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类星体PKS1448—232的吸收线光谱

科学通报 1982年第17期27卷 1057-1061页

作者：陈建生,Donald C.Morton,Bruce A.Peterson,alan e.wright,David L.Jauncey 中国科学院北京天文台英国-澳大利亚天文台澳大利亚国立大学Stromlo and Siding Spring天文台澳大利亚国立射电天文台澳大利亚联邦科工组织无线电物理部

一、引言在系统地进行南天射电源的光学证认工作中,Savage,Bolton和wright于1977年发现了射电源PKS1448—232和—个具有紫外色超的16（?）4恒星状的天体的位置相符合,并给出它的光学证认图。他们利用英-澳3（?）9反光望远镜对这个天体... 详细信息

一、引言在系统地进行南天射电源的光学证认工作中,Savage,Bolton和wright于1977年发现了射电源PKS1448—232和—个具有紫外色超的16（?）4恒星状的天体的位置相符合,并给出它的光学证认图。他们利用英-澳3（?）9反光望远镜对这个天体进行了低色散光谱的观测,证实了它是一个发射线红移为Zcm=2.22的类星体,并发现这个类星体的光谱存在有丰富的吸收线,其中大部分的吸收线分布在波长小于Lα的区域。因此,PKS1448-232被列入英-澳望远镜的《类星体吸收线光谱研究》的观测对象之一。该类星体的精确坐标是:

关键词：类星体吸收线望远镜 PKS1448 短波高频(3兆赫-30兆赫) 活动星系类星体发射线

Nocardiopsistins A-C:New angucyclines with anti-MRSA activity isolated from a marine sponge-derived Nocardiopsis ***-J378

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Synthetic and Systems Biotechnology 2018年第4期3卷 246-251页

作者： Dongbo Xu Keshav K.Nepal Jing Chen Dedra Harmody Haining Zhu Peter J.McCarthy Amy e.wright Guojun Wang Harbor Branch Oceanographic Institute Florida Atlantic University5600 US 1 NorthFort PierceFL34946United States Department of Molecular and Cellular Biochemistry University of Kentucky741 South LimestoneLexingtonKY40536United States

Marine natural products have become an increasingly important source of new drug leads during recent *** an attempt to identify novel anti-microbial natural products by bioprospecting deep-sea Actinobacteria,three new angucyclines,nocardiopsistins A-C,were isolated from Nocardiopsis *** ***,the supplementation of the rare earth salt Lanthanum chloride(LaCl3)during fermentation of HB-J378 significantly increased the yield of these *** structures of nocardiopsistins A-C were identified by 1D and 2D NMR and HR-MS *** A-C have activity against MRSA(methicillin-resistant Staphylococcus aureus)with MICs of 3.12–12.5μg/mL;the potency of nocardiopsistin B is similar to that of the positive control,*** analysis of the draft genome of HB-J378 identified a set of three core genes in a biosynthetic gene cluster that encode a typical aromatic or type II polyketide synthase(PKS)system,including ketoacyl:ACP synthaseα-subunit(KSα),β-subunit(KSβ)and acyl carrier protein(ACP).The production of nocardiopsistins A-C was abolished when the three genes were knocked out,indicating their indispensable role in the production of nocardiopsistins.

关键词： Nocardiopsis Nocardiopsistins Angucycline Anti-MRSA Actinobacteria LaCl_(3)

Progress in carbon dioxide separation and capture: A review

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Journal of environmental Sciences 2008年第1期20卷 14-27页

作者： Hongqun Yang Zhenghe Xu Maohong Fan Rajender Gupta Rachid B Slimane alan e Bland Ian wright Department of Chemical and Materials engineering University of Alberta EdmontonABT6G2G6 Canada School of Materials Science and Technology Georgia Institute of Technology Atlanta GA 30332 USA Gas Technology Institute Des Plaines IL 60018 USA Western Research Institute Laramie Wyoming 82072 USA Oak Ridge National Laboratory P.O. Box 2008 Oak Ridge TN 37831 USA

This article reviews the progress made in CO2 separation and capture research and engineering. Various technologies, such as absorption, adsorption, and membrane separation, are thoroughly discussed. New concepts such as chemical-looping combustion and hydrate-based separation are also introduced briefly. Future directions are suggested. Sequestration methods, such as forestation, ocean fertilization and mineral carbonation techniques are also covered. Underground injection and direct ocean dump are not covered.

关键词： coal flue gas carbon dioxide sorbent absorption adsorption membrane separation sequestration

Soil enzyme Activities and Organic Matter Composition Affected by 26 Years of Continuous Cropping

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Pedosphere 2016年第5期26卷 618-625页

作者： Fugen DOU alan L.wright Rao S.MYLAVARAPU JIANG Xianjun John e.MATOCHA Texas A&M AgriLife Research Center at Beaumont BeaumontTX 77713(USA) University of Florida Indian River Research&Education CenterFt.PierceFL 34945(USA) University of Florida Soil&Water Science Dept.GainesvilleFL 32611(USA) Southwest University College of Resources and EnvironmentChongqing(China) Texas A&M University Agricultural Research and Extension CenterCorpus ChristiTX 78406(USA)

The study was to determine the long-term effects of subtropical monoculture and rotational cropping systems and fertilization on soil enzyme activities and soil C, N, and P levels. Cropping systems included continuous sorghum(Sorghum bicolor L.), cotton(Gossypium hirsutum L.), corn(Zea mays L.), and cotton/sorghum rotations after 26 years of treatment imposition. Soil under continuous sorghum and continuous corn had 15% and 11%, respectively, greater C concentrations than soil under continuous *** C was 10% higher at 0–7.5 cm than at 7.5–15 cm. Total N followed similar trends with soil depth as organic C. Continuous sorghum had 19% higher total N than other crop species and rotations. With fertilization, continuous cotton had the highest total P at 0–7.5 cm and sorghum had the highest at 7.5–15 cm. Soil total P was 14% higher at 0–7.5 than at 7.5–15 cm, and fertilization increased 15% total P compared to unfertilized soil. Arylsulfatase, alkaline phosphatase, and β-d-glucosidase activity were the highest for sorghum and the lowest for cotton. Rotation increased enzyme activities compared to continuous cotton but not for continuous sorghum. Of all crop species and rotations, continuous cotton generally showed the lowest levels of organic matter and enzyme activities after 26 years. Fertilization significantly increased the yields for all cropping systems, but rotation had no significant effect on either sorghum or cotton lint yield compared to each crop grown in monoculture. Long-term cropping did not increase soil organic matter levels beyond short-term gains, indicating the difficulty in promoting C sequestration in subtropical soils.

关键词： C sequestration fertilization monoculture rotation subtropical soil

Mechanical suppression of breast cancer cell invasion and paracrine signaling to osteoclasts requires nucleo-cytoskeletal connectivity

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Bone Research 2020年第4期8卷 393-405页

作者： Xin Yi Laura e.wright Gabriel M.Pagnotti Gunes Uzer Katherine M.Powell Joseph M.Wallace Uma Sankar Clinton T.Rubin Khalid Mohammad Theresa A.Guise William R.Thompson Department of Physical Therapy School of Health and Rehabilitation SciencesIndiana UniversityIndianapolisIN 46202USA Department of Medicine Division of EndocrinologySchool of MedicineIndiana UniversityIndianapolisIN 46202USA Department of Mechanical and Biomedical engineering Boise State UniversityBoiseID 83725USA Department of Biomedical engineering Purdue School of Engineering and TechnologyPurdue UniversityIndianapolisIN 46202USA Department of Anatomy&Cell Biology Indiana UniversityIndianapolisIN 46202USA Department of Biomedical engineering Stony Brook UniversityStony BrookNY 11794USA

exercise benefits the musculoskeletal system and reduces the effects of *** effects of exercise are multifactorial,where metabolic changes and tissue adaptation influence *** signals,a principal component of exercise,are anabolic to the musculoskeletal system and restrict cancer *** examined the mechanisms through which cancer cells sense and respond to low-magnitude mechanical signals introduced in the form of ***-magnitude,high-frequency vibration was applied to human breast cancer cells in the form of low-intensity vibration(LIV).LIV decreased matrix invasion and impaired secretion of osteolytic factors PTHLH,IL-11,and ***,paracrine signals from mechanically stimulated cancer cells,reduced osteoclast differentiation and resorptive *** the nucleus by knockdown of SUN1 and SUN2 impaired LIV-mediated suppression of invasion and osteolytic factor *** increased cell stiffness;an effect dependent on the LINC *** data show that mechanical vibration reduces the metastatic potential of human breast cancer cells,where the nucleus serves as a mechanosensory apparatus to alter cell structure and intercellular signaling.

关键词： invasion impaired skeletal

Vector-mode multiplexing brings an additional approach for capacity growth in optical fibers

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Light(Science & Applications) 2018年第1期7卷 1031-1033页

作者： alan e Willner Department of electrical engineering University of Southern CaliforniaLos AngelesCA 90089-2565USA

The paper‘Direct fiber vector eigenmode multiplexing transmission seeded by integrated optical vortex emitters’by J Liu1 has successfully demonstrated that different data-carrying vector modes can be used to increase capacity through data-carrying,full-vectorial fiber eigenmode multiplexing communications in circular optical *** work uses compact,integrated optics to achieve capacity scaling by directly exploiting orthogonal spatial vector eigenmodes.

关键词： optical fiber multiplexing

Carbon pool trends and dynamics within a subtropical peatland during long-term restoration

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ecological Processes 2017年第1期6卷 449-462页

作者： Paul Julian II Stefan Gerber alan L.wright Binhe Gu Todd Z.Osborne University of Florida Soil and Water Sciences DepartmentFt.PierceFL 34945USA. University of Florida Soil and Water Sciences DepartmentGainesvilleFL 32611USA. South Florida Water Management District Water Quality BureauWest Palm BeachFL 33406USA. University of Florida Whitney Laboratory for Marine BioscienceSt AugustineFL 32080USA.

Introduction:The Florida everglades has undergone significant ecological change spanning the continuum of disturbance to *** the restoration effort is not complete and the ecosystem continues to experience short duration perturbations,a better understanding of long-term C dynamics of the everglades is needed to facilitate new restoration *** study evaluated temporal trends of different aquatic carbon(C)pools of the northern everglades Protection Area over a 20-year period to gauge historic C cycling *** inorganic C(DIC),dissolved organic C(DOC),particulate organic C(POC),and surface water carbon dioxide(pCO2(aq))were investigated between May 1,1994 and April 30,***:Annual mean concentrations of DIC,DOC,POC,and pCO2(aq)significantly decreased through time or remained constant across the Water Conservation Areas(WCAs).Overall,the magnitude of the different C pools in the water column significantly differed between *** of CO2 was dynamic across the everglades ranging from 420 to 2001 kg CO2 year−***,the historic trend in CO2 flux from the marsh declined across our study area while pCO2(aq)largely remained somewhat constant with the exception of Water Conservation Area 2 which experienced significant declines in pCO2(aq).Particulate OC concentrations were consistent between WCAs,but a significantly decreasing trend in annual POC concentrations was ***:Hydrologic condition and nutrient inputs significantly influenced the balance,speciation,and flux of C pools across WCAs suggesting a subsidy-stress response in C dynamics relative to landscape scale responses in nutrient *** interplay between nutrient inputs and hydrologic condition exert a driving force on the balance between DIC and DOC production via the metabolism of organic matter which forms the base of the aquatic food *** the restoration trajectory as water quality and hydrology continues to improve,it is expect

关键词： Inorganic carbon Organic carbon Carbon dioxide Particulate carbon Hydrology Nutrients

Nanoscale viscoelastic properties and adhesion of polydimethylsiloxane for tissue engineering

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Acta Mechanica Sinica 2014年第1期30卷 2-6页

作者： J.Chen K.e.wright M.A.Birch School of Mechanical & Systems engineering Newcastle University Arthritis Research UK (ARUK) Tissue engineering Centre Institute of Cellular MedicineNewcastle UniversityUK Research UK (ARUK) Tissue engineering Centre Institute of Cellular MedicineNewcastle UniversityUK St James’ University Hospital University of Leeds UK

It has shown that altering crosslink density of biopolymers will regulate the morphology of Mesenchymal Stem Cells （MSCs） and the subsequent MSCs differentia- tion. These observations have been found in a wide range of biopolymers. However, a recent work published in Nature Materials has revealed that MSCs morphology and differen- tiation was unaffected by crosslink density of polydimethyl- siloxane （PDMS）, which remains elusive. To understand such unusual behaviour, we use nanoindentation tests and modelling to characterize viscoelastic properties and sur- face adhesion of PDMS with different base：crosslink ratio varied from 50：1 （50D） to 10：1 （10D）. It has shown that lower crosslink density leads to lower elastic moduli. De- spite lower nanoindentation elastic moduli, PDMS with lowest crosslink density has higher local surface adhesion which would affect cell-biomaterials interactions. This work suggests that surface adhesion is likely another important physical cue to regulate cell-biomaterials interactions.

关键词： Bioploymer- Nanoindentation- Viscoelasticity Surface adhesion

Autotrophic and Heterotrophic Nitri?cation in a Highly Acidic Subtropical Pine Forest Soil

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Pedosphere 2016年第6期26卷 904-910页

作者： FAeFLeN J.Sarwee LI Shiwei XIN Xiaoping alan L.wright JIANG Xianjun College of Resources and environment Southwest UniversityChongqing 400715(China) everglades Research&education Center University of FloridaBelle Glade FL 33430(USA)

The occurrence of nitri?cation in some acidic forest soils is still a subject of ***?cation of main nitri?cation pathways in acidic forest soils is still largely *** yellow soil(Oxisol) samples were selected to test whether nitri?cation can occur or not in acidic subtropical pine forest *** contributions of autotrophs and heterotrophs to nitri?cation were studied by adding selective nitri?cation inhibitor *** NH^+_4-N concentrations decreased,but NO^-_3-N concentrations increased signi?cantly for the no-nitrapyrin control during the ?rst week of incubation,indicating that nitri?cation did occur in the acidic subtropical *** calculated net nitri?cation rate was 0.49 mg N kg^(-1)d^(-1)for the no-nitrapyrin control during the ?rst week of *** amendment resulted in a signi?cant reduction of NO^-_3-N *** nitri?cation rate averaged0.28 mg N kg^(-1)d^(-1)and the heterotrophic nitri?cation rate was 0.21 mg N kg^(-1)d^(-1)in the ?rst ***-oxidizing bacteria(AOB) abundance increased slightly during incubation,but nitrapyrin amendment signi?cantly decreased AOB amo A gene copy numbers by about 80%.However,the ammonia-oxidizing archaea(AOA) abundance showed signi?cant increases only in the last 2weeks of incubation and it was also decreased by nitrapyrin *** results indicated that nitri?cation did occur in the present acidic subtropical pine forest soil,and autotrophic nitri?cation was the main nitri?cation *** AOA and AOB were the active biotic agents responsible for autotrophic nitri?cation in the acidic subtropical pine forest soil.

关键词： acidic yellow soil ammonia-oxidizing archaea ammonia-oxidizing bacteria net nitrification rate nitrapyrin nitrification inhibitor