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Perturbation of Wood Cellulose Synthesis Causes Pleiotropic Effects in Transgenic Aspen

Molecular Plant 2011年第2期4卷 331-345页

作者： Chandrashekhar R Joshi Shivegowda Thammannagowda Takeshi Fujino Ji-Qing Gou Utku Avci Candace H. Haigler Lisa M. McDonnell Shawn D. Mansfield Bemnet Mengesha Nicholas C. Carpita darby harris Seth DeBolt Gary F. Peter Biotechnology Research Center School of Forest Resources and Environmental Sciences Michigan Technological University Houghton MI 49931 USA Department-of Bioenergy Science and Technology Chonnam National University Buk-Gu Gwangju 500-757 Korea Department of Crop Science North Carolina State University 4405 Williams Hall Raleigh NC 27695 USA Department of Plant Biology North Carolina State University 4405 Williams Hall Raleigh NC 27695 USA Department of Wood Science University of British Columbia 4030-2424 Main Mall Vancouver BC V6T 1Z4 Canada Purdue University Botany and Plant Pathology 915 West State Street West Lafayette IN 47907 USA Department of Horticulture N-318 Agricultural Sciences Center University of Kentucky Lexington KY 40546 USA School of Forest Resources and Conservation 326 Newins-Ziegler Hall PO Box 110410 University of Florida Gainesville FL 32611 USA

Genetic manipulation of cellulose biosynthesis in trees may provide novel insights into the growth and development of trees. To explore this possibility, the overexpression of an aspen secondary wall-associated cellulose synthase （PtdCesAS） gene was attempted in transgenic aspen （Populus tremuloides L.） and unexpectedly resulted in silencing of the transgene as well as its endogenous counterparts. The main axis of the transgenic aspen plants quickly stopped growing, and weak branches adopted a weeping growth habit. Furthermore, transgenic plants initially developed smaller leaves and a less extensive root system. Secondary xylem （wood） of transgenic aspen plants contained as little as 10% cellulose normalized to dry weight compared to 41% cellulose typically found in normal aspen wood. This massive reduction in cellulose was accompanied by proportional increases in lignin （35%） and non-cellulosic polysaccharides （55%） compared to the 22% lignin and 36% non-cellulosic polysaccharides in control plants. The transgenic stems pro- duced typical collapsed or ＇irregular＇ xylem vessels that had altered secondary wall morphology and contained greatly reduced amounts of crystalline cellulose. These results demonstrate the fundamental role of secondary wall cellulose within the secondary xylem in maintaining the strength and structural integrity required to establish the vertical growth habit in trees.

关键词： Aspen cellulose synthesis transgenic trees xylem development cell wall lignin irregular xylem growth crystallinity.

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Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural Regeneration Research 2025年第3期20卷 803-804页

作者： Glenn A.harris Lauren R.Hirschfeld Rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3R) or 4-repeat(4R) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases

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Geochemical and Pb-Sr-Nd isotopic compositions of granitoids from western Qinling belt: Constraints on basement nature and tectonic affinity

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Science China Earth Sciences 2007年第2期50卷 184-196页

作者： Nigel harris Department of Earth Sciences The Open University Milton Keynes MK7 6AA UK

Geochemical and Pb-Sr-Nd isotopic compositions of five Indosinian granitoid intrusions from the western Qinling belt provide insights into basement nature and tectonic affinity. The results show that the western Qinling granitoids incline towards basic in their bulk chemical composition. The granitoids belong to high-K to shoshonitic series with K2O/Na2O=1.04-1.86 and are dominantly metaluminous with A/CNK=0.90-1.05 (most samples have A/CNK of <1.0). They have similar trace elemental compo- sitional patterns. In Sr-Nd isotopic compositions, they display some extent heterogeneity with Isr=0.70682-0.70845, εNd(t)=?4.85 to ?9.17 and TDM=1.26-1.66 Ga. They are characterized by high ra- diogenic Pb isotopic compositions. Their initial Pb isotopic ratios are 206Pb/204Pb=17.996-18.468, 207Pb/204Pb=15.565-15.677 and 208Pb/204Pb=38.082-38.587. Geochemical and Sr-Nd isotopic composi- tions reveal that magma for the granitoids was derived from partial melting of high-K (Rb) basaltic rocks, which might be formed in 900-1400 Ma. It is suggested that a large amount of the Proterozoic high-K (Rb) basaltic rocks, which underlie the Phanerozoic sedimentary cover, constitute the crustal basement of the western Qinling belt. Pb-Sr-Nd isotopic compositional comparison between the east- ern Qinling and the western Qinling Indosinian granitoids indicates that the crustal basement of the western Qinling is distinct from that of the eastern Qinling. The Baoji-Chengdu railway close to south-north orientation can be taken as an approximate boundary between both basements. The Pb-Nd isotopic compositional characteristics of the western Qinling granitoids suggest that the basement of the western Qinling belt has an affinity with the Yangtze block.

关键词： granitoid geochemistry basement nature tectonic affinity West Qinling

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A New Semi-Lagrangian Finite Volume Advection Scheme Combines the Best of Both Worlds

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Advances in Atmospheric Sciences 2021年第9期38卷 1608-1609页

作者： Lucas harris NOAA/Geophysical Fluid Dynamics Laboratory Princeton University Forrestal Campus201 Forrestal RoadPrincetonNJ 08540-6649USA

Advection,or transport by wind,is fundamental to numerical weather and climate *** is especially important to solve the equations governing the distribution of heat,moisture,pollutants,and so *** classes of advection schemes have become dominant in recent ***-Lagrangian (SL;Diamantakis,2013) methods form the advection equation in its"Lagrangian"or flow-following form and use the winds (either prescribed or predicted) to trace trajectories backwards from a grid point to their original location on the previous time step.

关键词： prescribed backward Finite

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A fast and accurate model for the creation of explosion fragments with improved fragment shape and dimensions

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Defence Technology（防务技术） 2022年第2期18卷 159-169页

作者： David Felix Ian Colwill Paul harris School of Computing Engineering&MathematicsUniversity of BrightonBrightonUK Engineering and Design(Alumni) University of SussexBrightonUK

Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead *** their execution times are *** protection systems need to make very fast predictions,before a fast attacking weapon hits the *** execution times are also needed in real time simulations where the impact of many different computer models is being ***,FEA explosion models are not appropriate for these real-time *** research presented in this paper delivers a fast simulation model based on Mott’s equation that calculates the number and weight of fragments created by an *** addition,the size and shape of fragments,unavailable in Mott’s equation,are calculated using photographic evidence and a distribution of a fragment’s length to its *** model also identifies the origin of fragments on the warhead’s *** results are verified against experimental data and a fast execution time is achieved using uncomplicated simulation *** developed model then can be made available for real-time simulation and fast computation.

关键词： Distribution of fragments Fragment shape Real-time simulation Cylindrical explosion

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Temporal allocation of metabolic tolerance in the body of beet armyworm in response to three gossypol-cotton cultivars

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Science China(Life Sciences) 2009年第12期52卷 1140-1147页

作者： Marvin K harris Department of Entomology Texas A&M University of USA

The nutrient composition and enzyme activities in larvae of the beet armyworm, Spodoptera exigua (Hbner), fed on high, medium or low gossypol cotton cultivars were examined at different time intervals. Significantly lower free fatty acid was observed in larvae fed for 6 h on high gossypol 'M9101' compared to larvae fed on the low (ZMS13) and intermediate (HZ401) gossypol cultivars. Significantly higher trypsin activity was observed in larvae fed on high gossypol 'M9101' for 24 h compared to those fed for 1, 4 and 6 h. Significantly higher catalase and total superoxide dismutase enzyme activities were observed in larvae of S. exigua fed on high gossypol 'M9101' compared with low gossypol cultivars 'ZMS13' and 'HZ401' for 1, 4, 6 and 24 h. However, significantly lower carboxylesterase and acetylcholinesterase enzyme activities were found in larvae fed on high gossypol 'M9101' compared with the other cultivars for 1, 4, 6 and 24 h. The interaction between cotton variety and beet armyworm infestation time significantly affected the carboxylesterase enzyme activity in S. exigua. The characterization of the effects of plant allelochemicals on herbivorous larvae is important for aiding understanding of plant-insect interaction as well as in devising solutions to pest problems by breeding plant resistance, identifying metabolic targets for insecticide development, etc.

关键词： Spodoptera exigua gossypol free fatty acid detoxification enzyme acetylcholinesterase total superoxide dismutase

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A review of progress on nano-aperture VCSEL Invited Paper

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Chinese Optics Letters 2008年第10期6卷 748-754页

作者： Sonny Vo James S.harris Solid State and Photonics Laboratory Stanford UniversityStanfordCalifornia94305USA

This paper reviews the progress on nano-aperture vertical-cavity surface-emitting lasers （VCSELs）. The design, fabrication, and polarization control of nano-aperture VCSELs are reviewed. With the nanoaperture evolving from conventional circular and square aperture to unique C-shaped, H-shaped, I-shaped, and bowtie-shaped aperture, both the near-field intensity and near-field beam confinement from nanoaperture VCSELs are significantly improved. As a high-intensity compact light source with sub-100- nm spot size, nano-aperture VCSELs are promising to realize many new near-field optical systems and applications.

关键词： VCSEL view A review of progress on nano-aperture VCSEL Invited Paper

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Hammer-Impact SH-Wave Seismic Reflection Methods in Neotectonic Investigations: General Observations and Case Histories from the Mississippi Embayment, U.S.A.

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Journal of China University of Geosciences 2009年第3期20卷 513-525页

作者： James B harris Millsaps College Jackson MississippiUSA

Shallow shear-wave seismic reflection imaging, using a sledgehammer and mass energy source and standard processing, has become increasingly common in mapping near-surface geologic features, especially in water-saturated, unconsolidated sediments. Tests of the method in the Mississippi Embayment region of the central United States show interpretable reflection arrivals in the depth range of 〈10 m to 〉100 m with the potential for increased resolution when compared with compressional-wave data. Shear-wave reflection prof＇des were used to help interpret the significance of neotectonic surface deformation at five sites in the Mississippi Embayment. The interpreted profiles show a range of shallow structural styles that include reverse faulting, fault propagation folding, and reactivated normal faulting, and provide crucial subsurface evidence in support of paleoseismologic trenching and shallow drilling.

关键词： shear wave seismic reflection neotectonics.

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Tribological behavior of polydopamine/polytetrafluoroethylene coating on laser textured stainless steel with Hilbert curves

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Friction 2023年第7期11卷 1307-1319页

作者： Firuze SOLTANI-KORDSHULI Nathaniel harris Min ZOU Department of Mechanical Engineering University of ArkansasFayetteville AR 72701USA Center for Advanced Surface Engineering University of ArkansasFayetteville AR 72701USA

Shallow Hilbert curve patterns with easily programmable texture density were selected for laser texturing of stainless steel *** different texture path segment lengths(12 and 24 μm)and four different laser power percentages(5%,10%,15%,and 20%)were *** textured and smooth substrates were coated with thin polydopamine/polytetrafluoroethylene(PDA/PTFE)coatings for tribological property *** effects of texture density(texture area coverage)and laser power on the durability and friction of the coated surfaces were *** texturing the substrates improved the coating durability up to 25 times,reduced the friction coefficient,and prevented coating global *** textures fabricated with a laser power of 15%and a texture path segment length of 12 μm yielded the best coating *** textures provided the interlocking for the PTFE coating and thus prevented its global ***,the PTFE inside the texture grooves replenished the solid lubricant worn away in the wear track and prolonged the coating wear life.

关键词： polytetrafluoroethylene(PTFE) coating durability laser texturing Hilbert curve stainless steel

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Cryogenic wedges on the NE Qinghai-Tibet and Ordos Plateaus:Their characteristics,origin and OSL dating

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Research in Cold and Arid Regions 2021年第6期13卷 463-473页

作者： Stuart A.harris Department of Geography University of CalgaryCalgaryAlbertaT2N 1N4Canada

Cryogenic wedges developed due to very cold,rather arid conditions during the maximum of the last cold event when the drying up of the neighboring China Sea resulted in the failure of the East Asian *** the climate ameliorated and the Monsoon rains reappeared,ice-wedges *** warming permitted thawing of the ice infillings accompanied by replacement of the ice by sediments partly from the host ground as well as from the surface by wind or sheet *** cases of extreme surface water flow on slopes after 10 ka B.P.,small baydjarakhs typically c.50 cm high developed,only to have the resulting hollows infilled by sediments carried by wind and/or sheet *** shallow structures form a network on top of many of the cryogenic *** complex history makes dating the ages of the wedges difficult using OSL ***,past field work ignored the problem of the angle of the cut face to the direction of the wedge infilling when sampling the contents of the narrow wedges,resulting in potential contamination of the samples with the host *** of the larger deposits should be alright,but the likelihood of contamination makes the interpretation of the resulting OSL dates from the narrow wedges *** wedges consisting of primary mineral infillings should still have similar OSL dates with depth for a given wedge,but the distinction between ice-wedge infillings and soil wedges is difficult since both can exhibit older dates of the infillings with *** available data suggests that ice-wedges were significantly more common than sediment-filled primary wedges.A protocol to avoid having to obtain large numbers of OSL dates by more careful field sampling and the use of grain size determinations is provided in the Appendix.

关键词： cryogenic wedges OSL dating NE Qinghai-Tibet Plateau differentiation of primary and secondary wedges baydjarakhs in arid climates

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