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A little goes a long way: CLE peptides mediate phloem initiation

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Journal of Integrative Plant Biology 2019年第10期61卷 1034-1035页

作者： Amala John zachary L.Nimchuk Department of Biology University of North Carolina at Chapel Hill

The root system of a tree can often extend many-fold the diameter of the tree;it provides physical support, dissolved minerals and water but relies on a constant supply of nutrients from photosynthetically active tissues in aboveground organs. The phloem is re-sponsible for such transport and the success of a plant relies heavily on the integrity of the phloem in its root system.

关键词： CLE peptides mediate initiation

Scavenging of reactive oxygen and nitrogen species with nanomaterials

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Nano Research 2018年第10期11卷 4955-4984页

作者： Carolina A. Ferreira Dalong Ni zachary T. Rosenkrans Weibo Cai Department of Radiology University of Wisconsin-Madison Madison W153705 USA

Reactive oxygen and nitrogen species （RONS） are essential for normal physiological processes and play important roles in cell signaling, immunity, and tissue homeostasis. However, excess radical species are implicated in the development and augmented pathogenesis of various diseases. Several antioxidants may restore the chemical balance, but their use is limited by disappointing results of clinical trials. Nanoparticles are an attractive therapeutic alternative because they can change the biodistribution profile of antioxidants, and possess intrinsic ability to scavenge RONS. Herein, we review the types of RONS, how they are implicated in several diseases, and the types of nanoparticles with inherent antioxidant capability, their mechanisms of action, and their biological applications.

关键词： mnanomaterials reactive oxygen species(ROS) reactive nitrogen species ROS scavenging antioxidant nanoparticles

PVC Formulation of Anastrepha suspensa Pheromones Suitable for Field Studies

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Engineering 2021年第11期7卷 1646-1650页

作者： Daniel Kuzmich zachary A.Kawagoe Spencer S.Walse San Joaquin Valley Agricultural Sciences Center Agricultural Research ServiceUnited States Department of AgricultureParlierCA 93648USA Agricultural and Environmental Chemistry graduate group University of CaliforniaDavisCA 95616USA

Tephritid flies threaten the production of fruits around the *** the Americas,populations of the genus Anastrepha are monitored with trapping networks as part of pest management ***,we report the formulation of male Anastrepha suspensa(Loew)pheromones,(±)-anastrephin and(±)-epianastrephin,into a poly(vinyl chloride)(PVC)polymer-based lure ready for trap *** PVC polymer disks(100 mg)contain 10%by weight of(±)-epianastrephin and(±)-anastrephin in a naturally occurring 7:3 diastereomeric ratio,*** of the pheromones from the disks into an airstream was evaluated as a function of the abiotic environmental parameters,absolute humidity and *** data supports a diffusion-controlled mechanism of release from the matrix with first-order rate constants that decreased about ten-fold as the temperature was lowered from 30 to 15*** such,the emission of volatile pheromones from the disks is suitable to last for several weeks in the *** kinetic approach,which can be easily extended to the diffusion-controlled release of other attractants from polymeric matrices,yields laboratory predictions of the potential for environmental loss prior to conducting field bioassays.

关键词： Anastrepha Anastrephin Epianastrephin PVC lure Controlled release

Improving metal reflectors by suppressing surface plasmon polaritons: a priori calculation of the internal reflectance of a solar cell

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Light(Science & Applications) 2013年第1期2卷 32-37页

作者： zachary C Holman Stefaan De Wolf Christophe Ballif Swiss Federal Institute of Technology Lausanne(EPFL)Institute of Microengineering(IMT)Photovoltaics and Thin-Film Electronics LaboratoryCH-2000 NeuchaˆtelSwitzerland

Imperfect internal reflectance of near-bandgap light reduces the performance of all solar cells,and becomes increasingly detrimental as absorbers become *** consider light incident on the silicon/dielectric/metal structure at the back of rear-passivated crystalline silicon solar cells with surface textures that are large enough for geometric *** calculating the absorbance in the metal as a function of the angle of incidence,we discover three results that are important for understanding and improving rear reflectors in many types of solar ***,significant parasitic absorption occurs in the metal layer in two cases:s-and p-polarized propagating modes(near-normal angles of incidence)when the dielectric thickness is adjusted to cause destructive interference of the reflected beams,and p-polarized evanescent modes(angles of incidence above the semiconductor/dielectric critical angle)that excite surface plasmon polaritons at the metal ***,the latter loss dominates;a well-designed rear dielectric passivation layer must suppress the penetration of evanescent waves to the ***,when used as an input in a simple analytical model,the average rear internal reflectance calculated by assuming a Lambertian angular distribution of light accurately predicts the total reflectance and absorbance of a solar cell.

关键词： light trapping photovoltaics plasmon silicon solar cell

Effect of heat treatment conditions on the passivation behavior of WE43CMg-Y-Nd alloy in chloride containing alkaline environments

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Journal of Magnesium and Alloys 2017年第2期5卷 147-165页

作者： Jakraphan Ninlachart zachary Karmiol Dev Chidambaram Krishnan SRaja Chemical and Materials Engineering University of IdahoMoscowID 83844-1021USA Chemical and Materials Engineering University of NevadaRenoNV 89557-0388USA

Mg–Y–Nd alloy(WE43C or Elektron 43)is a heat treatable magnesium wrought alloy that can be used up to 250 ℃ for aerospace *** alloy has excellent mechanical properties(UTS:up to 345 MPa at room temperature)and improved corrosion *** passivation studies were conducted on this alloy under different heat treatment conditions in 0.1 M NaOH solution with the addition of chloride from 0 to 1000 *** passive potential range typically extended to more than 1.5 VAg/*** transpassive potential was not dependent on the heat treatment condition of the alloy when the chloride concentration increased up to 500 ***,pitting protection potential varied with the heat treatment condition when the chloride addition was 500 ppm or *** specimen surface was analyzed using scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and Raman spectroscopy to understand the passivation behavior of this *** passivated surface of the WE43C specimens indicated that the surface layer consisted of MgO,Mg(OH)_(2),and rare earth oxide phases,and the heat treatment conditions did not significantly affect the composition of the surface film.

关键词： Elektron 43 Magnesium alloy Corrosion Passivation Chloride

Developing an identities-based approach to support more robust resilience and recovery in heritage planning and management

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Built Heritage 2023年第2期7卷 3-14页

作者： zachary M.Jones Théodora Pappas DASTU Politecnico di MilanoMilanItaly

Resilience has become an increasingly important concept in the cultural heritage feld,particularly in the aftermath of the unprecedented challenges the COVID-19 global pandemic ***,on a conceptual and practical level,resilience remains closely linked to the technical conservation of built heritage,and there remains a need to develop broader approaches inclusive of cultural and socioeconomic *** article investigates the potential applicability of theoretical concepts linked to identity and identities in heritage planning to help fll these gaps and develop approaches that consider resilience and are better able to address a range of unanticipated *** frst review the literature and policy documents to defne and identify the potential for identities-based *** then examine the case of Matera,an extremely fragile world heritage site in southern Italy that has been continuously inhabited for more than 8000 years and provides a relevant example of *** explore the trends and efects of globalised tourism development before the pandemic and the post pandemic emergence of more local/regional and slow tourism patterns,largely based on cultural solutions to local development challenges and knowledge *** this comparison,we analyse the potential and limitations of introducing identities-based concepts into heritage planning as a more robust way to enhance resilience and prepare cities for unexpected future crises.

关键词： identity heritage management plans Matera resilience locally based development mode

A Strong Stability Preserving Analysis for Explicit Multistage Two-Derivative Time-Stepping Schemes Based on Taylor Series Conditions

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Communications on Applied Mathematics and Computation 2019年第1期1卷 21-59页

作者： zachary grant Sigal gottlieb David C.Seal Department of Computational and Applied Mathematics Oak Ridge National LaboratoryOak RidgeUSA Department of Mathematics University of Massachusetts DartmouthDartmouthUSA Department of Mathematics U.S.Naval AcademyAnnapolisUSA

High-order strong stability preserving(SSP)time discretizations are often needed to ensure the nonlinear(and sometimes non-inner-product)strong stability properties of spatial discretizations specially designed for the solution of hyperbolic ***-derivative time-stepping methods have recently been increasingly used for evolving hyperbolic PDEs,and the strong stability properties of these methods are of *** our prior work we explored time discretizations that preserve the strong stability properties of spatial discretizations coupled with forward Euler and a second-derivative ***,many spatial discretizations do not satisfy strong stability properties when coupled with this second-derivative formulation,but rather with a more natural Taylor series *** this work we demonstrate sufficient conditions for an explicit two-derivative multistage method to preserve the strong stability properties of spatial discretizations in a forward Euler and Taylor series *** call these strong stability preserving Taylor series(SSP-TS)*** also prove that the maximal order of SSP-TS methods is p=6,and define an optimization procedure that allows us to find such SSP *** types of these methods are presented and their efficiency ***,these methods are tested on several PDEs to demonstrate the benefit of SSP-TS methods,the need for the SSP property,and the sharpness of the SSP time-step in many cases.

关键词： Strong stability preserving Taylor series.Hyperbolic conservation laws Two derivative Runge Kutta

Melamine modified carbon felts anode with enhanced electrogenesis capacity toward microbial fuel cells

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Journal of Energy Chemistry 2017年第1期26卷 81-86页

作者： Yang'en Xie Zhaokun Ma Huaihe Song zachary A.Stoll Pei Xu State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing University of Chemical Technology Department of Civil Engineering New Mexico State University

Surface electropositivity and low internal resistance are important factors to improve the anode performance in microbial fuel cells (MFCs). Nitrogen doping is an effective way for the modification of traditional carbon materials. In this work, heat treatment and melamine were used to modify carbon felts to enhance electrogenesis capacity of MFCs. The modified carbon felts were characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), atomic force microscopy (AFM) and malvern zeta potentiometer. Results show that the maximum power densities under heat treatment increase from 276.1 to 423.4 mW/m(2) (700 degrees C) and 461.5 mW/m(2) (1200 degrees C) and further increase to 472.5 mW/m(2) (700 degrees C) and 515.4 mW/m(2) (1200 degrees C) with the co-carbonization modification of melamine. The heat treatment reduces the material resistivity, improves the zeta potential which is beneficial to microbial adsorption and electron transfer. The addition of melamine leads to the higher content of surface pyridinic and quaternary nitrogen and higher zeta potential. It is related to higher MFCs performance. generally, the melamine modification at high temperature increases the feasibility of carbon felt as MFCs's anode materials. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： Microbial fuel cells Anode materials Carbon felts Modification Melamine

genes important for survival or reproduction in Varroa destructor identified by RNAi

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Insect Science 2019年第1期26卷 68-75页

作者： zachary Y.Huang guowu Bian Zhiyong Xi Xianbing Xie Department of Laboratory Animal Science Nanchang UniversityNanchangJiangxiChina Department of Entomology Michigan State UniversityEast LansingMIUSA Department of Microbiology and Molecular genetics Michigan State UniversityEast LansingMI USA Ecology Evolutionary Biology and BehaviorMichigan State UniversityEast LansingMIUSA BEACON Center for the Study of Evolution in Action Michigan State UniversityEast LansingMIUSA

The Varroa mite,(Varroa destructor),is the worst threat to honey bee health *** explore the possibility of using RNA interference to control this pest, we determined the effects of knocking down various genes on Varroa mite survival and ***-stranded RNA (dsRNA)of six candidate genes (Da,Pros26S,RpL8, RpL11,RpPO and RpS13)were synthesized and each injected into Varroa mites,then mite survival and reproduction were *** of dsRNA for Da (Daughterless)and Pros26S (gene for proteasome 26S subunit adenosine triphosphatase)caused a significant reduction in mite survival,with 3.57%±1.94% and 30.03%±11.43% mites surviving at 72 h post-inj ection (hpi),*** mites injected with green fluorescent protein (gFP)-dsRNA showed survival rates of 81.95%±5.03% and 82.36 ±2.81%,respectively. Injections of dsRNA for four other genes (RpL8,RpL11,RpPO and RpS13)did not affect survival significantly,enabling us to assess their effect on Varroa mite *** number of female offspring per mite was significantly reduced for mites injected with dsRNA of each of these four genes compared to their gFP-dsRNA *** of the target genes was verified by real-time polymerase chain reaction for two genes important for reproduction (RpL8,RpL11)and one gene important for survival (Pros26S). In conclusion,through RNA interference,we have discovered two genes important for mite survival and four genes important for mite *** genes could be explored as possible targets for the control of Varroa destructor in the future.

关键词： Apis mellijera reproduction RNAi survival Varroa destructor