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Neural Network-Based Second Order Reliability Method(NNBSORM)for laminated Composite Plates in Free Vibration

Computer Modeling in Engineering & Sciences 2018年第4期115卷 105-129页

作者： Mena E.Tawfik Peter l.Bishay edward E.Sadek Aerospace Engineering Department Faculty of EngineeringCairo UniversityEgypt Mechanical and Aerospace Engineering Department Rutgersthe State University of New JerseyNew BrunswickNJUSA Mechanical Engineering Department College of Engineering and Computer ScienceCalifornia State UniversityNorthridgeCAUSA.

Monte Carlo Simulations(MCS),commonly used for reliability analysis,require a large amount of data points to obtain acceptable accuracy,even if the Subset Simulation with Importance Sampling(SS/IS)methods are *** Second Order Reliability Method(SORM)has proved to be an excellent rapid tool in the stochastic analysis of laminated composite structures,when compared to the slower MCS ***,SORM requires differentiating the performance function with respect to each of the random variables involved in the *** most suitable approach to do this is to use a symbolic solver,which renders the simulations very slow,although still faster than ***,the inability to obtain the derivative of the performance function with respect to some parameters,such as ply thickness,limits the capabilities of the classical *** this work,a Neural Network-Based Second Order Reliability Method(NNBSORM)is developed to replace the finite element algorithm in the stochastic analysis of laminated composite plates in free *** of the ability to obtain expressions for the first and second derivatives of the NN system outputs with respect to any of its inputs,such as material properties,ply thicknesses and orientation angles,the need for using a symbolic solver to calculate the derivatives of the performance function no longer *** proposed approach is accordingly much faster,and easily allows for the consideration of ply thickness *** present analysis showed that dealing with ply thicknesses as random variables results in 37%increase in the laminate’s probability of failure.

关键词： Reliability analysis artificial neural network composite laminates subset simulation importance sampling Monte Carlo

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Increased Benthic Algal Primary Production in Response to the Invasive Zebra Mussel (Dreissena polymorpha) in a Productive Ecosystem,Oneida lake,New York

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Journal of Integrative Plant Biology 2008年第11期50卷 1452-1466页

作者： Rebecca K.Cecala Christine M.Mayer Kimberly l.Schulz edward l.Mills Biology Department Syracuse University Biology Deptartment Department of Environmental Sciences and lake Erie Center University of Toledo State University of New York School of Environmental Science and Forestry Cornell Biological Field Station and Department of Natural Resources Cornell University

Increased water clarity associated with zebra mussel （Dreissena polymorpha） populations may favor benthic algal primary production in freshwater systems previously dominated by pelagic phytoplankton production. While zebra mussel-mediated water clarity effects on benthic primary production have been implicated in published reports, few production estimates are available. This study estimates benthic primary production in Oneida lake, NY before and after zebra mussel invasion （1992）, using measured photosynthetic parameters （P^Bmax, α^β and β） from sampled benthic algal communities. In the summers of 2003 and 2004, primary production was measured as O2 evolution from algal communities on hard （cobble） and soft （sediment） substrate from several depths. We also backcast estimates of benthic primary production from measurements of light penetration since 1975. Estimates of whole-lake epipelic and epilithic algal primary production showed a significant （4%） increase and exhibited significantly less interannual variability subsequent to the establishment of zebra mussels. We applied our model to two lakes of differing trophic status; the model significantly overestimated benthic primary production in a hypereutrophic lake, but there was no significant difference between the actual and predicted primary production values in the oligotrophic lake. The hypereutrophic lake had higher zebra mussel densities than Oneida （224 vs. 41 per sample respectively）. Though total community respiration （measured in total darkness） was factored into our model predictions of production, our model may need modification when heterotrophic respiration is a large portion of total community metabolism.

关键词： Dreissena ecosystem engineering nonindigenous species Oneida lake periphyton primary production.

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Plasticity of mycangia in Xylosandrus ambrosia beetles

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Insect Science 2019年第4期26卷 732-742页

作者： You li Yong-Ying Ruan edward l. Stanley James Skelton Jiri Hulcr School of Forest Resources and Conservation University of Florida Gainesville Florida USA School of Applied Chemistry and Biological Technology Postdoctoral Innovation Practice Base Shenzhen Polytechnic Shenzhen. Guangdong. China Florida Museum of Natural History University of Florida Gainesville Florida USA Entomology and Nematology Department University of Florida Gainesville Florida USA

Insects that depend on microbial mutualists evolved a variety of organs to transport the microsymbionts while dispersing. The ontogeny and variability of such organs is rarely studied, and the microsymbiont*s effects on the animal tissue development remain unknown in most cases. Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae or Platypodinae) and their mutualistic fungi are an ideal system to study the animalfungus interactions. While the interspecific diversity of their fungus transport organ一 mycangia—is well-known, their developmental plasticity has been poorly described. To determine the ontogeny of the mycangium and the influence of the symbiotic fungus on the tissue development, we dissected by hand or scanned with micro-CT the mycangia in various developmental stages in five Xylosandrus ambrosia beetle species that possess a large, mesonotal mycangium: Xylosandrus amputatus. Xylosandrus compactus, Xylosandrus crassiusculus, Xylosandrus discolor, and Xylosandrus germanus. We processed 181 beetle samples from the United States and China. All five species displayed three stages of the mycangium development:(1) young teneral adults had an empty, deflated and cryptic mycangium without fungal mass;(2) in fully mature adults during dispersal, the promesonotal membrane was inflated, and most individuals developed a mycangium mostly filled with the symbiont, though size and symmetry varied;and (3) after successful establishment of their new galleries, most females discharged the bulk of the fun gal inoculum and deflated the mycangium. Experimental aposymbiotic individuals demonstrated that the pronotal membrane invaginated independently of the presence of the fungus, but the fungus was required for inflation. Mycangia are more dynamic than previously thought, and their morphological changes correspond to the phases of the symbiosis. Importantly, studies of the fungal symbionts or plant pathogen transmission in ambrosia beetles need to consider which developmen

关键词： callow micro-CT mycangium symbiont-induced symbiosis teneral

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Visualization of atomic scale reaction dynamics of supported nanocatalysts during oxidation and ammonia synthesis using in-situ environmental(scanning) transmission electron microscopy

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Journal of Energy Chemistry 2021年第6期30卷 281-290,I0007页

作者： Michael R.Ward Robert W.Mitchell edward D.Boyes Pratibha l.Gai The York Nanocentre University of YorkYork YO105DDUK Department of Physics University of YorkYork YO105DDUK Department of Electronic Engineering University of YorkYork YO105DDUK Department of Chemistry University of YorkYork YO105DDUK

Reaction dynamics in gases at operating temperatures at the atomic level are the basis of heterogeneous gas-solid catalyst reactions and are crucial to the catalyst *** noble metal nanocatalysts such as platinum are of interest in fuel cells and as diesel oxidation catalysts for pollution control,and practical ruthenium nanocatalysts are explored for ammonia *** and graphitic carbons are of interest as supports for the *** considerable literature on the catalytic processes on graphite and graphitic supports,reaction dynamics of the nanocatalysts on the supports in different reactive gas environments and operating temperatures at the single atom level are not well *** we present real time in-situ observations and analyses of reaction dynamics of Pt in oxidation,and practical Ru nanocatalysts in ammonia synthesis,on graphite and related supports under controlled reaction environments using a novel in-situ environmental(scanning) transmission electron microscope with single atom *** recording snapshots of the reaction dynamics,the behaviour of the catalysts is *** images reveal single metal atoms,clusters of a few atoms on the graphitic supports and the support *** all play key roles in the mobility,sintering and growth of the *** experimental findings provide new structural insights into atomic scale reaction dynamics,morphology and stability of the nanocatalysts.

关键词： In-situ visualization Atomic scale reaction dynamics In-situ environmental scanning transmission electron microscopy with single atom resolution Supported nanoparticles Ammonia synthesis Oxidation reactions

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The acceleration of a high-charge electron bunch to 10 GeV in a 10-cm nanoparticle-assisted wakefield accelerator

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Matter and Radiation at Extremes 2024年第1期9卷 15-24页

作者： Constantin Aniculaesei Thanh Ha Samuel Yoffe lance labun Stephen Milton edward McCary Michael M.Spinks Hernan J.Quevedo Ou Z.labun Ritwik Sain Andrea Hannasch Rafal Zgadzaj Isabella Pagano Jose A.Franco-Altamirano Martin l.Ringuette Erhart Gaul Scott V.luedtke Ganesh Tiwari Bernhard Ersfeld Enrico Brunetti Hartmut Ruhl Todd Ditmire Sandra Bruce Michael E.Donovan Michael C.Downer Dino A.Jaroszynski Bjorn Manuel Hegelich University of Texas at Austin AustinTexas 78712USA SUPA Department of Physics University of StrathclydeGlasgowScotland G4 ONGUnited Kingdom Tau Systems Inc.AustinTexas 78701USA lawrence livermore National laboratory LivermoreCalifornia 94550USA los Alamos National laboratory Los AlamosNew Mexico 87545USA Brookhaven National laboratory UptonNew York 11973USA ludwig-Maximilians-Universität MunichGermany

An intense laser pulse focused onto a plasma can excite nonlinear plasma *** appropriate conditions,electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic *** scheme is called a laser wakefield *** this work,we present results from a laser wakefield acceleration experiment using a petawatt-class laser to excite the wakefields as well as nanoparticles to assist the injection of electrons into the accelerating phase of the *** find that a 10-cm-long,nanoparticle-assisted laser wakefield accelerator can generate 340 pC,10±1.86 GeV electron bunches with a 3.4 GeV rms convolved energy spread and a 0.9 mrad rms *** can also produce bunches with lower energies in the 4–6 GeV range.

关键词： acceleration nanoparticle charge

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Soil resource availability and its effect on the ecophysiology and establishment of Stipa pulchra

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Journal of Plant Ecology 2019年第4期12卷 603-614页

作者： Robert l.Fitch Erin J.Questad edward G.Bobich Department of Biological Sciences California State Polytechnic UniversityPomona3801 West Temple Avenue PomonaCA 91768USA

Aims The objectives of this study were to(i)determine the importance of soil moisture and soil nitrogen availability as resource requirements for the establishment of Stipa pulchra,(ii)to examine how changes in slope within a local habitat can affect the accumulation of soil moisture and soil nitrogen and(iii)to measure the physiological re-sponses of *** among such slope *** The field experiment occurred in the San JoséHills of Southern California on the California State Polytechnic University,Pomona *** were established within three different slope loca-tions(shallow,moderate and steep)within four separate *** nitrogen treatments(ambient,addition and removal)were replicated within each slope location for all four canyons,and five *** plants were planted in each *** nitrogen accumula-tion and soil moisture,as well as other abiotic variables,were meas-ured across the varied slope locations and nitrogen *** measured the cover,stress,and reproduction of *** plants for 2 years and used a mesocosm experiment to determine how ***-chra responds to varying water and nitrogen *** Findings Stipa pulchra had a strong positive response to the wettest watering treatment and a weak response to nitrogen addition in the meso-cosm *** the field experiment,*** responded positively in moderate slope locations and did not respond to ni-trogen treatments,possibly due to *** patterns of soil moisture were driven by slope,soil compaction and solar *** nitrogen accumulation did not vary among slope *** restoration of ***,priority should be placed on managing soil moisture availability and determining suitable edaphic factors.

关键词： establishment ecophysiology slope soil moisture soil properties nitrogen deposition

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Synthesis of the C50 diastereomers of the C33–C51 fragment of stambomycin D

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Organic Chemistry Frontiers 2022年第2期9卷 445-449页

作者： Yongchen Wang Venkaiah Chintalapudi Haraldur G.Gudmundsson Gregory l.Challis edward A.Anderson Chemistry Research laboratory University of Oxford12 Mansfield RoadOxfordOX13TAUK Department of Chemistry and Warwick Integrative Synthetic Biology Centre University of WarwickCoventryCV47ALUK Department of Biochemistry and Molecular Biology and ARC Centre of Excellence for Innovations in Peptide and Protein Science Biomedicine Discovery InstituteMonash UniversityClaytonVictoria 3800Australia

As products of genome mining,the stereochemical assignment of the macrolide antibiotics stambomycins A-D has been made on the basis of sequence analysis of the associated polyketide synthase,aside from two stereocentres at C28 and *** we describe syntheses of the two C50 diastereomers of the C33-C51 region of the stambomycins,which support the PKS-based configurational assignment,and establish a strategy suitable for access to the extended stambomycin framework.

关键词： stereo assignment centre

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Assembly of IMPDH2-Based,CTPS-Based,and Mixed Rod/Ring Structures Is Dependent on Cell Type and Conditions of Induction

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Journal of Genetics and Genomics 2015年第6期42卷 287-299页

作者： Gerson Dierley Keppeke S.John Calise edward K.l.Chan luis Eduardo C.Andrade Rheumatology Division Federal University of Sao Paulo Department of Oral Biology University of Florida Immunology Division Fleury Medicine and Health Laboratories

Inhibition of guanosine triphosphate（GTP） and cytidine triphosphate（CTP） biosynthetic pathways induces cells to assemble rod/ring（RR） structures,also named cytoophidia,which consist of the enzymes cytidine triphosphate synthase（CTPS） and inosine-50-monophosphate dehydrogenase 2（IMPDH2）.We aim to explore the interaction of CTPS and IMPDH2 in the generation of RR *** la and COS-7 cells were cultured in normal conditions or in the presence of 6-diazo-5-oxo-l-norleucine（DON）,ribavirin,or mycophenolic acid（MPA）.Over 90% of DON-treated cells presented RR *** He la cells,35% of the RR structures were positive for IMPDH2 alone,26% were CTPS alone,and 31% were IMPDH2/CTPS mixed,while in COS-7 cells,42% of RR were IMPDH2 alone,41% were CTPS alone,and 10% were IMPDH2/CTPS *** and MPA treatments induced only IMPDH2-based *** were also transfected with an N-terminal hemagglutinin（NHA）-tagged CTPS1 *** 95% of NHA-CTPS1 transfected cells with DON treatment presented IMPDH2-based RR and almost 100% presented CTPS1-based RR;when treated with ribavirin,over 94% of transfected cells presented IMPDH2-based RR and 37% presented CTPS1-based RR,whereas 2% of untreated transfected cells presented IMPDH2-based RR and 28% presented CTPS1-based *** results may help in understanding the relationship between CTP and GTP biosynthetic pathways,especially concerning the formation of filamentous RR structures.

关键词： Nucleotide synthesis Enzyme aggregation Enzyme inhibition IMPDH2 CTPS

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Whole genome phylogeny of Gallus: introgression and data-type effects

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Avian Research 2020年第1期11卷 1-15页

作者： George P.Tiley Akanksha Pandey Rebecca T.Kimball edward l.Braun J.Gordon Burleigh Department of Biology University of FloridaGainesvilleFL 32611USA Department of Biology Duke UniversityDurhamNC 27708USA

Background: Previous phylogenetic studies that include the four recognized species of Gallus have resulted in a number of distinct topologies, with little agreement. Several factors could lead to the failure to converge on a consistent topology, including introgression, incomplete lineage sorting, different data types, or insufficient ***: We generated three novel whole genome assemblies for Gallus species, which we combined with data from the published genomes of Gallus gallus and Bambusicola thoracicus(a member of the sister genus to Gallus). To determine why previous studies have failed to converge on a single topology, we extracted large numbers of orthologous exons, introns, ultra-conserved elements, and conserved non-exonic elements from the genome assemblies. This provided more than 32 million base pairs of data that we used for concatenated maximum likelihood and multispecies coalescent analyses of ***: All of our analyses, regardless of data type, yielded a single, well-supported topology. We found some evidence for ancient introgression involving specific Gallus lineages as well as modest data type effects that had an impact on support and branch length estimates in specific analyses. However, the estimated gene tree spectra for all data types had a relatively good fit to their expectation given the multispecies ***: Overall, our data suggest that conflicts among previous studies probably reflect the use of smaller datasets(both in terms of number of sites and of loci) in those analyses. Our results demonstrate the importance of sampling large numbers of loci, each of which has a sufficient number of sites to provide robust estimates of gene trees. low-coverage whole genome sequencing, as we did here, represents a cost-effective means to generate the very large data sets that include multiple data types that enabled us to obtain a robust estimate of Gallus phylogeny.

关键词： Galliformes Incomplete lineage sorting Junglefowl Multispecies coalescent Phasianidae Phylogenomics Species tree

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lifestyle and dietary factors in the prevention of letha prostate cancer

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Asian Journal of Andrology 2012年第3期14卷 365-374,I0004,I0005页

作者： Kathryn M Wilson edward l Giovannucci lorelei A Mucci Depa rtment of Epidemiology Harvard School of Public Health Boston MA 02115 USA Department of Nutrition Harvard School of Public Health Boston MA 02115 USA Channing laboratory Brigham and Women＇s Hospital Harvard Medical School Boston MA 02115 USA

The prevention of lethal prostate cancer is a critical public health challenge that would improve health and reduce suffering from this disease. In this review, we discuss the evidence surrounding specific lifestyle and dietary factors in the prevention of lethal prostate cancer. We present a summary of evidence for the following selected behavioral risk factors： obesity and weight change, physical activity, smoking, antioxidant intake, vitamin D and calcium, and coffee intake.

关键词： epidemiology diet life style obesity physical activity prevention prostate cancer

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