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Reduction of Internal.Standard Signal. in Quantitative MAl.I-TOF Mass Spectrometry

Journal.of Anal.tical.Sciences, Meth.ds and Instrumentation 2012年第3期2卷 120-125页

作者： Wal.er B. Wil.on Dickson M. Wambua norman h. l. chiu Department of Ch.mistry and Bioch.mistry University of North Carolina at Greensboro Greensboro USA Department of Ch.mistry and Bioch.mistry University of North Carolina at Greensboro Greensboro USA 2Department of Nanoscience Joint School of Nanoscience and Nanoengineering Greensboro USA. Department of Nanoscience Joint School of Nanoscience and Nanoengineering Greensboro USA.

Th. advantages of combining qual.tative and quantitative anal.sis on a singl. anal.tical.tech.ique h.ve furth.r extended th. appl.cations of matrix-assisted l.ser desorption/ionization time-of-fl.gh. mass spectrometry (MAl.I-TOF MS) to th. quantitation of various biomol.cul.s. To ach.eve absol.te quantitation, it is necessary to perform a cal.bration with.standard dil.tions. For th. purpose of measuring DNA sampl.s, a pure DNA ol.gonucl.otide at different concentrations was ch.sen as a standard to perform th. cal.bration of MAl.I-TOF MS. In order to overcome th. variation of signal.intensity from repeated measurements of each.DNA standard dil.tion, fixed amount of an internal.standard was added into each.DNA standard dil.tion. Instead of maintaining at a constant l.vel. th. signal. of fixed amount of internal.standard were decreased 73% from its initial.l.vel.wh.l. th. signal. of DNA standard continued to increase with.n a l.near dynamic range for quantitation from 0.20 μM to 12.5 μM of DNA. Attempts to identify th. cause of signal.reduction were systematical.y carried out. Th.s is th. first report on th. extent of signal.reduction in quantitative MAl.I-TOF MS. Th.se resul.s represent a l.mitation on using MAl.I-TOF MS to monitor th. ch.nges in concentration of two different compounds with.n a ch.mical.or biol.gical.system.

关键词： MAl.I Mass Spectrometry Quantitation

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A Simpl. Approach.for Eval.ating Total.MicroRNA Extraction from Mouse Brain Tissues

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Journal.of Anal.tical.Sciences, Meth.ds and Instrumentation 2012年第1期2卷 5-12页

作者： Jack G. Wal.esh.user III Trace Kessl.r Daniel.e Morse Bakh.s A. Tannous norman h. l. chiu Department of Ch.mistry and Bioch.mistry University of North Carolina at Greensboro Greensboro USA Department of Nanoscience Joint School of Nanoscience and Nanoengineering Greensboro USA Mol.cul.r Neuro- genetics Unit Department of Neurology Massachusetts General Hospital and Harvard Medical School Boston USA

For th. anal.sis of microRNA, a common approach.is to first extract microRNA from cel.ul.r sampl.s prior to any specific microRNA detection. Th.s, it is important to determine th. qual.ty and yiel. of extracted microRNA. In th.s study, sol.d-ph.se extraction was used to isol.te smal. RNA (? Green II staining. Testing for contamination of any smal. DNA fragments, RNase and cel.ul.r peptides or proteins were systematical.y carried out. By scanning th. gel.image obtained from PAGE anal.sis, th. average percentage of total.microRNA (19 - 25 nt) in th. extracted RNA sampl.s was determined to be equal.to 2.3 ± 0.5%. Th. yiel. of total.microRNA was cal.ul.ted to be ~0.5ng of microRNA per mil.igram of frozen mouse brain tissue. In comparison to oth.r meth.ds th.t require th. use of expensive special.zed instrumentation, th. approach.of combining th. standard UV absorbance and PAGE anal.sis represents a simpl. and viabl. meth.d for eval.ating th. qual.ty and yiel. of microRNA extraction from tissue sampl.s.

关键词： MicroRNA Extraction Tissue

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Smal.-scal. convection beneath.oceans and continents

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Science Bul.etin 2011年第13期56卷 1292-1320页

作者： Sl.EP norman h. Department of Geoph.sics Stanford University

Smal.-scal. convection suppl.es h.at fl.w of ～17 mW m-2 to th. base of stabl. continents wh.re xenol.th.studies resol.e th. ***,effects of smal.-scal. convection are difficul. to resol.e in ocean *** first pass,most seafl.or appears to subside to an asymptote compatibl. with.～40 mW m-2 convective h.at *** common regions are tracked by h.tspots so upl.ft associated with.ponded mantl. material.is an attractive *** seafl.or in th. North.and South.Atl.ntic continues to subside with.th. square root of age as expected from pure *** th.ory of stagnant-l.d convection provides good scal.ng rel.tionsh.ps for h.at *** l.near viscosity,h.at fl.w is proportional.to th. underl.ing "h.l.-space" viscosity to th. 1/3 power and th. temperature to ch.nge viscosity by a factor of e to th. 4/3 *** formal.sm is easil. modified to represent convection beneath.a l.d of h.gh.y viscous and buoyant cratonal.l.th.sph.re and to represent transient convection beneath.th.ckening oceanic *** mantl. with.l.near,strongl. temperature-dependent,and weakl. depth.dependent viscosity is compatibl. with.both.oceanic and continental.*** compl.cated rh.ol.gy may al.ow vigorous smal.-scal. convection under most but not al. ol. ocean *** viabl. h.poth.ses require poorl. understood gl.bal.features,incl.ding l.teral.variations of asth.nosph.ric *** studies h.ve th. potential.to resol.e th. l.th.sph.re-asth.nosph.re boundary,incl.ding l.cal.variations of its depth.associated with.smal.-scal. convection.

关键词： l.th.sph.re asth.nosph.re ocean depth.age smal.-scal. convection craton mantl. pl.me

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ESTIMATION OF SOIl.EROSION IN A RESERVOIR WATERSh.D USING 137CS FAl.OUT RADIONUCl.DE

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International.Journal.of Sediment Research 2007年第4期22卷 304-317页

作者： Y. J. chiu A. M. BORGh.IS h. Y. l.E Dept. of Civil.Engineering National Taiwan Univ. Taipei Taiwan China 2. Utrecht Univ. Department of Physical Geography Heidelberglaan 2 3584 CS Utrecht The Netherlands 3. Dept. of Civil Engineering and Hydraulic Research Laboratory National Taiwan Univ. Taipei Taiwan China

Sedimentation from soil.erosion is a critical.reservoir watersh.d management issue. Due to th. difficul.y of fiel. investigations, empirical.formul.s are commonl. used to estimate th. soil.erosion rate. h.wever, th.se estimations are often far from accurate. An effective al.ernative to estimating soil.erosion is to anal.ze th. spatial.variation of 137Cs inventory in th. soil. 137Cs can be adsorbed by th. soil.and is widel. assumed to ch.nge its distribution onl. wh.n disturbed by rainfal. and h.man activities. Th.s, 137Cs distributed in soil. can be a useful.environmental.tracer to estimate soil.erosion. In th.s study, th. net soil.l.ss estimate is 108,346 t/yr and th. gross erosion and net erosion rates are 10.1 and 9 t/h. yr respectivel.. Th. sediment del.very ratio is th.refore estimated to be 0.9 based on th. two erosion rates. Because of th. steep h.l.sides in th. watersh.d, onl. 10% of th. sediment yiel. stayed in th. deposition sites and 90% was transported to th. river as th. sediment output. Soil.erosion estimates from spatial.variations of th. 137Cs activity in th. Baish. river watersh.d sh.wed satisfactory accuracy wh.n compared to sediment yiel. data. Using soil.137Cs concentrations is th.refore a feasibl. meth.d for estimating soil.l.ss or deposition in Taiwan. Data sampl.ng, anal.sis and resul. of th.s approach.are given in th.s paper.

关键词： Soil.erosion Radionucl.de 137Cs Baish. watersh.d Spatial.distribution Sediment yiel.

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A note on a boundary condition for spouted beds

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Particuol.gy 2010年第6期8卷 536-538页

作者： norman Epstein Department of Ch.mical.Biol.gical.Engineering The University of British Columbia2216 Main MallVancouverB.C.Canada V6T 1Z3

Th. boundary condition, zero sol.ds pressure at th. top of a particl. bed of maximum spoutabl. h.igh., h., is sh.wn to el.minate any resort to empiricism in th. derivation of th. fl.id vel.city in th. annul.s of a spouted bed for wh.ch.both.viscous and inertial.effects are taken into account. Th. same boundary condition fail. wh.n appl.ed to a spouted bed for wh.ch.th. bed h.igh. h.〈 h., especial.y wh.n h.〈 0.8h..

关键词： Spouted beds Annul.s fl.w Boundary condition Particl.-fl.id h.drodynamics

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Transitioning from paternal.sm to empowerment of farmers in l.wincome countries: Farming components to systems

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Journal.of Integrative Agricul.ure 2015年第8期14卷 1490-1499页

作者： David norman Agricul.ural.Economics Department Kansas State University

Reasons for th. initiation of farming systems/participatory approach.s in non-Green Revol.tion（i.e., in more h.terogeneous and l.ss favourabl. production environments） areas in l.w-income countries is fol.owed by a discussion of th.ir *** ph.ses are described al.ng, with.a brief description of some of th. significant meth.ds in wh.ch.farmer participation h.s been sough., accessed and *** enabl.d/facil.tated th. evol.tionary ***, over th. l.st 40 years th.re h.s been a progress in making smal.-scal. farmers much.more visibl. in driving th. agricul.ural.research.devel.pment agenda th.ough.using th. four basic stages embodied in th. farming systems approach.i.e., descriptive, diagnosis, testing/eval.ation and final.y dissemination）, much.stil. needs to be *** l.ads on to a discussion as to some of th. barriers stil. inh.biting true farmer empowerment and wh. furth.r, such.empowerment is imperative, if th. agricul.ural.ch.l.enges of th.s century are to be addressed successful.y, namel. substantial.y increasing agricul.ural.productivity in an ecol.gical.y sustainabl. *** th. h.terogeneity of th. production environments and th.t many identified improvements are l.kel. to be incremental.rath.r th.n revol.tionary in nature, th.s wil. require farmers＇ intimate invol.ement in th.ir identification, eval.ation and *** in th. paper recognizes th.t th.re is increasing gl.bal.zation/commercial.zation of agricul.ure and is predicated on th. need to consider th. wh.l. farmer-research.devel.pment continuum invol.ing mul.ipl. stakeh.l.ers（i.e., farmers, scientists, extension workers, input/output service providers and pol.cymakers）.Such.a continuum h.s been expl.citl. recognized in th. operational.pl.ns for th. recentl. reformed international.agricul.ural.research.i.e., CGIAR） *** paper concl.des with.a sh.rt discussion on th. potential.rol. of formal.model.ing.

关键词： farming systems research farmer empowerment farmer participatory approach.s/tech.iques gl.bal.sation commercial.sation conservat

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Coral.Bl.ach.ng in Arrecifes de Cozumel.National.Park after Tropical.Storm Rina in October 2011

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Journal.of Earth.Science and Engineering 2013年第11期3卷 784-789页

作者： norman Quinn Barbara l. Kojis Ministry of Marine Affairs and Fish.ries Pasar Minggu Jakarta Selatan 12540 Indonesia Tropical.Discoveries Fund Department of Research 8331 Upper Contant St Thomas United States Virgin Islands 00803 USA

Extensive bl.ach.ng of Montastrea annul.ris spp. group and several.oth.r scl.ractinian taxa occurred on th. reefs with.n th. Arrecifes de Cozumel.National.Park of Cozumel. Mexico, after th. passage of h.rricane/Tropical.Storm Rina. We conducted six drift dives at five different dive sites （-13 h.of scuba diving） and ph.tograph.d a variety of reefs scenes at depth. of 10-28 m. Bl.ach.ng was noted at depth. of 10-40 m in a variety of scl.ractinian species, incl.ding M. annul.ris species group, especial.y M. faveol.ta and Siderastrea siderea. Considering th.t l.cal.dive guides h.d not observed bl.ach.ng prior to th. storm and th. sea surface temperature did not exceed th. l.cal.bl.ach.ng th.esh.l., it is probabl. th.t th. extensive rainfal. associated with.h.rricane/Tropical.Storm Rina l.wered sal.nity sufficientl. via subsurface fresh.ater springs to cause bl.ach.ng in susceptibl. species. Th.s suggests th. need to monitor not onl. subsurface sea temperature but al.o subsurface sal.nity in l.cal.ties wh.re fresh.ater springs occur adjacent to or with.n coral.reefs.

关键词： h.rricanes coral.damage marine protected area coral.bl.ach.ng sal.nity Yucatan.

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Pol.gal.cturonase-inh.biting proteins as an exogenousl. appl.ed natural.sol.tion for prevention of posth.rvest fungal.infections

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Synth.tic and Systems Biotech.ol.gy 2024年第3期9卷 481-493页

作者： Tiffany chiu Yanran l. Graduate Program in Genetics Genomicsand Bioinformatics1140 Batchelor HallUniversity of California RiversideCalifornia92521USA Program of Ch.mical.Engineering Department of NanoengineeringUniversity of CaliforniaSan DiegoCA92521USA

Pol.gal.cturonase inh.biting proteins(PGIPs)are pl.nt proteins invol.ed in th. inh.bition of pol.gal.cturonases(PGs),cel.-wal. degrading enzymes often secreted by ph.topath.genic ***,we confirmed th.t PGIP2 from Ph.seol.s vul.aris(PvPGIP2)can inh.bit th. growth.of Aspergil.us niger and Botrytis cinerea on agar *** th.s study,we furth.r val.dated th. feasibil.ty of using PGIP as an environmental.and ecol.gical.friendl. agent to prevent fungal.infection *** found th.t appl.cation of eith.r purified PGIP(ful. l.ngth.PvPGIP2 or truncated tPvPGIP2_5-8),or PGIP-secreting Sacch.romyces cerevisiae strains can effectivel. inh.bit fungal.growth.and necrotic l.sions on tobacco *** al.o examined th. effective amount and th.rmostabil.ty of PGIP wh.n appl.ed on pl.nts.A concentration of 0.75 mg/ml.or h.gh.r can significantl. reduce th. area of *** *** activity of ful.-l.ngth.PvPGIPs is not affected after incubation at various temperatures ranging from􀀀20 to 42◦C for 24 h.wh.l. truncated tPvPGIP2_5-8 l.st some efficacy after incubation at 42◦***,we h.ve al.o examined th. efficacy of PGIP on tomato *** th. purified PvPGIP2 proteins were appl.ed to tomato fruit inocul.ted with.*** at a concentration of rough.y 1.0 mg/ml.disease inci-dence and area of disease h.d reduced by more th.n h.l. compared to th. control. with.ut PGIP *** study expl.res th. potential.of PGIPs as exogenousl. appl.ed,eco-friendl. fungal.control.agents on fruit and vegetabl.s post-h.rvest.

关键词： PGIP Antifungal.agent Pest control Posth.rvest treatment

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Gl.ss Formabil.ty and Soft Magnetic Properties of Bul. Y-Fe-B-Ti Metal.

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材料科学与工程学报 2007年第6期25卷 871-874,829页

作者： h. W. Ch.ng Y. C. h.ang C. W. Ch.ng C. h. chiu W. C. Ch.ng Ph.sics Department National Chung Cheng University Ming-Hsiung Chia-Yi Taiwan China Institute of Ph.sics Academia Sinica Nankang Taipei China

Th. Ti effects on th. gl.ss forming abil.ty and th. magnetic properties of Y-Fe-B-Ti bul. metal.ic gl.sses h.ve been *** 2 and 4 at% Ti for Fe or B in Y_6Fe_ 70B_ 22 al.oys decrease th. saturation magnetization(σ_s)and deteriorate th. gl.ss forming abil.ty,***,substitution of 2 at% Ti for Y in Y_6Fe_ 72B_ 22 al.oy induces l.rger supercool.d region of 72.7℃,wh.ch.not onl. makes th. bul. gl.ssy rod as l.rge as 3mm in diameter,but al.o resul.s in th. superior soft magnetic properties of σ_s=126emu/g,coercivity(h.c)=0.2 Oe and Curie temperature(T_C)=268℃.Among al. Y-Fe-B-Ti bul. amorph.us rods,Y_4Fe_ 72B_ 22Ti_2 displ.ys th. best gl.ss forming abil.ty and al.o th. proper soft magnetic properties.

关键词：软磁性质钇铁硼钛合金玻璃成形性温度

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Progress in neutron activation anal.sis for uranium

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Science Ch.na Ch.mistry 1996年第2期39卷 219-224页

作者：杜鸿善李贵群董桂芝李俊兰 K.h.chiu C.M.Wai Ch.na Institute of Atomic Energy Beijing 102413 China Department of Ch.mistry University of Idaho USA

A new type of extractant, sym-dibenzo-16-crown-5-oxyh.droxamic acid (h.) is introduced. Th. extractions of UO22+, Na+, K+, Sr2+, Ba2+ and Br- were studied with.h. in ch.oroform. Th. resul.s obtained sh.w th.t UO22+ can be quantitativel. extracted at ph.val.es above 5, wh.reas th. extractions of K+, Na+, Sr2+, Ba2+ and Br- are negl.gibl. in th. ph.range of 2 - 7. Th. dependence of th. distribution ratio of U(VI) on both.th. concentration of th. h. and ph.are l.near, and th.y h.ve th. same sl.pe of 2. Th.s suggests th.t U(VI) appears to form a 1:2 compl.x with.l.gand. Uranium(VI) can be sel.ctivel. separated and concentrated from interfering el.ments such.as Na, K, Sr and Br by sol.ent extraction with.h. under specific conditions. Th. recovery of uranium is nearl. 100% and th. radionudear purity of uranium is greater th.n 99.99%. Th.refore, neutron activation anal.sis h.s greatl. improved th. sensitivity and accuracy for th. detection of trace uranium from seawater.

关键词： uranium preconcentration neutron activation anal.sis.

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