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Genomics of plant speciation

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Plant Communications 2023年第5期4卷 112-133页

作者： Dan G.Bock Zhe Cai Cassandra Elphinstone Eric Gonza lez-Segovia Kaede Hirabayashi Kaichi Huang Graeme l.Keais Amy Kim gregory l.owens loren H.Rieseberg Department of Botany and Biodiversity Research Centre University of British ColumbiaVancouverBCCanada Department of Biology University of VictoriaVictoriaBCCanada

Studies of plants have been instrumental for revealing how new species *** several decades,botanical research has complemented and,in some cases,challenged concepts on speciation developed via the study of other organisms while also revealing additional ways in which species can ***,the ability to sequence genomes at an unprecedented pace and scale has allowed biologists to settle decades-long debates and tackle other emerging challenges in speciation ***,we review these recent genome-enabled developments in plant *** discuss complications related to identification of reproductive isolation(RI)loci using analyses of the landscape of genomic divergence and highlight the important role that structural variants have in speciation,as increasingly revealed by new sequencing ***,we review how genomics has advanced what we know of some routes to new species formation,like hybridization or whole-genome duplication,while casting doubt on others,like population bottlenecks and genetic *** genomics can fast-track identification of genes and mutations that confer RI,we emphasize that follow-up molecular and field experiments remain ***,genomics has clarified the outsized role of ancient variants rather than new mutations,particularly early during *** conclude by highlighting promising avenues of future *** include expanding what we know so far about the role of epigenetic and structural changes during speciation,broadening the scope and taxonomic breadth of plant speciation genomics studies,and synthesizing information from extensive genomic data that have already been generated by the plant speciation community.

关键词： genomic islands of speciation structural variation hybrid speciation polyploid speciation reproductive isolation standing genetic variation

Reduced texaphyrin:A ratiometric optical sensor for heavy metals in aqueous solution

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 19-27页

作者： Harrison D.Root gregory Thiabaud Jonathan l.Sessler Department of Chemistry The University of Texas at AustinAustinTX 78712-1224USA

We report here a water-soluble metal cation sensor system based on the as-prepared or reduced form of an expanded porphyrin,*** metal complexation,a change in the redox state of the ligand occurs that is accompanied by a color change from red to *** long employed for synthesis in organic media,we have now found that this complexation-driven redox behavior may be used to achieve the naked eye detectable colorimetric sensing of several number of less-common metal ions in aqueous *** to In(Ⅲ),Hg(Ⅱ),Cd(Ⅱ),Mn(Ⅱ),Bi(Ⅲ),Co(Ⅱ),and Pb(Ⅱ)cations leads to a colorimetric response within 10 *** process is selective for Hg(Ⅱ)under conditions of competitive ***,among the subset of responseproducing cations,In(Ⅲ)proved unique in giving rise to a ratiometric change in the ligand-based fluorescence features,including an overall increase in *** cation selectivity observed in aqueous media stands in contrast to what is seen in organic solvents,where a wide range of texaphyrin metal complexes may be *** formation of metal cation complexes under the present aqueous conditions was confirmed by reversed phase highperformance liquid chromatography,ultra-violet-visible absorption and fluorescence spectroscopies,and highresolution mass spectrometry.

关键词： texaphyrin fluorescent sensor ion-sensing indium mercury

Transcranial electrical stimulation in neurological disease

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Neural Regeneration Research 2022年第10期17卷 2221-2222页

作者： gregory l.Brown Michael T.Brown Neurished HersheyPAUSA

Increased lifespan is one of society’s greatest achievements,but this longevity increases the prevalence of diseases of aging,such as neurological ***,neurological disorders are the leading cause of disability and the second leading cause of deaths(Feigin et al.,2019).Furthermore,these diseases affect people in low-,medium-,and high-income countries(Feigin et al.,2019).Current technology to modify neurological burden is scarce,which poses numerous challenges for healthcare,global policy,and economic stability(Feigin et al.,2019).To face these challenges,brain stimulation technology,such as transcranial electrical stimulation(TES),has displayed exciting *** et al.(2017)provide a detailed overview of the safety and application of ***,electrodes are attached to the head and a weak current(e.g.,1-2 mA)is applied through the scalp,skull,and into the brain for 10-30 minutes to activate neurons(Antal et al.,2017).The technique is extremely safe with no serious adverse effects reported from thousands of sessions(Antal et al.,2017).The most common side effects are a tingling/itching sensation or redness at the stimulation site(Antal et al.,2017).However,these side effects can be minimized by reducing the electrode-skin impedance,slowly ramping up and ramping down TES,or using topical analgesics(Antal et al.,2017).The development of TES may repair neural dysfunction and stem the oncoming incidence of neurodegenerative disease.

关键词： stimulation sensation electrical

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limbic system as immune tissue

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Acta Pharmacologica Sinica 1999年第5期 80-81页

作者： gregory l FRICCHIONE Boston MA 02215 USA Brigham and Women’s Hospital Harvard Medical School Medical Psychiatry Service and Mind-Body Medical Institute

The purpose of this review is to examine the interaction of the limbic system and the cellular immune system from the perspective of evolutionary biology. While the limbic system exerts a level of control over the stress response systems, the cellular immune system spearheaded by the monocyte-macrophage is responsible for the acute phase response to *** potential role of the macrophage in certain neuropsychiatric and psychosomatic disorders,including dementia,delirium, schizophrenia, depression and autoimmune disease will be

关键词： limbic system as immune tissue

Different paths to sexual size dimorphism in two praying mantids, Pseudomantis albofimbriata and Hierodula majuscula

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Insect Science 2014年第2期21卷 227-233页

作者： louise E. Allen Katherine l. Barry gregory I. Holwell Department of Biological Sciences Macquarie University North Ryde NSW 2109 Australia School of Biological Sciences The University of Auckland Auckland New Zealand

Sexual size dimorphism （SSD） is widespread among diverse animal taxa and has attracted the attention of evolutionary biologists for over a century. SSD is likely to be adaptive and the result of divergent selection on different size optima for males and females, given their different roles in reproduction. The developmental trajectory leading to SSD may help us to understand how selection acts on male and female size. Here, we describe the growth and development of two Australian praying mantids, Pseudomantis albofimbriata and Hierodula majuscula including the number of moults, time to adulthood, size at each moult, and the degree of SSD. While both species exhibit the common pattern of female-biased SSD, the number of moults required for individuals to reach adulthood differed between males and females and between species. Despite their larger adult size, P. albofimbriata females require fewer moults and less time than males to reach adulthood, but are significantly larger than males from the second instar onwards. In contrast, H. majuscula males reached adulthood in fewer moults, and less time than females, however males and females did not differ in size until females went through their final moult into adulthood. H. majuscula also required more time and more moults to reach adulthood than 17. albofimbriata. We discuss these different developmental pathways in light of the existing knowledge of reproductive biology for each species. We also suggest that these differences may relate to the different phenologies that occur in strongly seasonal temperate environments compared with those in the tropics. This study provides evidence that SSD can result from two different patterns of growth and development in closely related species.

关键词： developmental trajectories Mantodea sexual size dimorphism

Role of sortase in Streptococcus mutans under the effect of nicotine

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International Journal of Oral Science 2013年第4期5卷 206-211页

作者： Ming-Yun li Rui-Jie Huang Xue-Dong Zhou Richard l gregory School of Dentistry Indiana University State Key laboratory of Oral Diseases West China Hospital of StomatologySichuan University Department of Pathology and laboratory Medicine School of MedicineIndiana University

Streptococcus mutans is a common Gram-positive bacterium and plays a significant role in dental caries. Tobacco and/or nicotine have documented effects on S. mutans growth and colonization. Sortase A is used by many Gram-positive bacteria, including S. mutans, to facilitate the insertion of certain cell surface proteins, containing an lPXTGX motif such as antigen 1/11. This study examined the effect of nicotine on the function of sortase A to control the physiology and growth of S. mutans using wild-type S. mutans NG8, and its isogenic sortase-defective and -complemented strains. Briefly, the strains were treated with increasing amounts of nicotine in planktonic growth, biofilm metabolism, and sucrose-induced and saliva-induced antigen I/ll-dependent biofilm formation assays. The strains exhibited no significant differences with different concentrations of nicotine in planktonic growth assays. However, they had significantly increased （P~〈 0.05） biofilm metabolic activity （2- to 3-fold increase） as the concentration of nicotine increased. Furthermore, the sortase-defective strain was more sensitive metabolically to nicotine than the wild-type or sortase-complemented strains. All strains had significantly increased sucrose-induced biofilm formation （2- to 3-fold increase） as a result of increasing concentrations of nicotine. However, the sortase-defective strain was not able to make as much sucrose- and saliva-induced biofilm as the wild-type NG8 did with increasing nicotine concentrations. These results indicated that nicotine increased metabolic activity and sucrose-induced biofilm formation. The saliva-induced biofilm formation assay and qPCR data suggested that antigen 1/11 was upregulated with nicotine but biofilm was not able to be formed as much as wild-type NG8 without functional sortase A.

关键词： dental caries metabolism nicotine sortase A Streptococcus mutans

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Synthesis and Ex Situ Doping of ZnTe and ZnSe Nanostructures with Extreme Aspect Ratios

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Nano Research 2009年第12期2卷 931-937页

作者： Joanne W.l.Yim Deirdre Chen gregory F.Brown Junqiao Wu Department of Materials Science and Engineering University of CaliforniaBerkeleyCA 94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

We report synthesis windows for growth of millimeter-long ZnTe nanoribbons and ZnSe nanowires using vapor *** tuning the local conditions at the growth substrate,high aspect ratio nanostructures can be synthesized.A Cu-ion immersion doping method was applied,producing strongly p-type conduction in ZnTe and ionic conduction in *** extreme aspect ratio wide-bandgap semiconductors have great potential for high density nanostructured optoelectronic circuits.

关键词： Aspect ratio doping nanowires zinc selenide zinc telluride

Data-Driven Microstructure and Microhardness Design in Additive Manufacturing Using a Self-Organizing Map

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Engineering 2019年第4期5卷 730-735页

作者： Zhengtao Gan Hengyang li Sarah J.Wolff Jennifer l.Bennett gregory Hyatt gregory J.Wagner Jian Cao Wing Kam liu Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA DMG MORI Hoffman EstatesIL 60192USA

To design microstructure and microhardness in the additive manufacturing(AM)of nickel(Ni)-based superalloys,the present work develops a novel data-driven approach that combines physics-based models,experimental measurements,and a data-mining *** simulation is based on a computational thermal-fluid dynamics(CtFD)model,which can obtain thermal behavior,solidification parameters such as cooling rate,and the dilution of solidified *** on the computed thermal information,dendrite arm spacing and microhardness are estimated using well-tested mechanistic *** microstructure and microhardness are determined and compared with the simulated values for *** visualize process-structure-properties(PSPs)linkages,the simulation and experimental datasets are input to a data-mining model-a self-organizing map(SOM).The design windows of the process parameters under multiple objectives can be obtained from the visualized *** proposed approaches can be utilized in AM and other data-intensive ***-driven linkages between process,structure,and properties have the potential to benefit online process monitoring control in order to derive an ideal microstructure and mechanical properties.

关键词： Additive manufacturing Data science Multiphysics modeling Self-organizing map Microstructure Microhardness Ni-based superalloy

Spectrophotometric analyses of hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX) in water

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Journal of Environmental Sciences 2015年第7期27卷 39-44页

作者： Cong Shi Zhonghou Xu Benjamin l.Smolinski Per M.Arienti gregory O'Connor Xiaoguang Meng Center for Environmental Systems Stevens Institute of Technology US Army RDECOM-ARDEC

A simple and accurate spectrophotometric method for on-site analysis of royal demolition explosive（RDX） in water samples was developed based on the Berthelot reaction. The sensitivity and accuracy of an existing spectrophotometric method was improved by：replacing toxic chemicals with more stable and safer reagents; optimizing the reagent dose and reaction time; improving color stability; and eliminating the interference from inorganic nitrogen compounds in water samples. Cation and anion exchange resin cartridges were developed and used for sample pretreatment to eliminate the effect of ammonia and nitrate on RDX analyses. The detection limit of the method was determined to be 100 μg/l. The method was used successfully for analysis of RDX in untreated industrial wastewater samples. It can be used for on-site monitoring of RDX in wastewater for early detection of chemical spills and failure of wastewater treatment systems.

关键词： Berthelot reaction Exchange resins RDXS pectrophotometric method Water

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