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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

Sexual selection in cane toads Rhinella marina： A male＇s body size affects his success and his tactics

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Current Zoology 2013年第6期59卷 747-753页

作者： Haley BOWCOCK gregory P. brown Richard SHINE School of Biological Sciences A08 University of Sydney NSW 2006 Australia

Abstract Male body size can play an important role in the mating systems of anuran amphibians. We conducted labora- tory-based trials with cane toads Rhinella （Bufo） marina from an invasive population in the wet-dry tropics of northern Australia, to clarify the effects of a male＇s body size on his reproductive success and behavior （mate choice）. Males were stimulated with a synthetic hormone to induce reproductive readiness. larger body size enhanced a male toad＇s ability to displace a smaller rival from amplexus, apparently because of physical strength： more force was required to dislodge a larger than a smaller amplectant male. A male＇s body size also affected his mate-choice criteria. Males of all body sizes were as likely to attempt amplexus with another male as with a female of the same size, and preferred larger rather than smaller sexual targets. However, this size prefe- rence was stronger in larger males and hence, amplexus was size-assortative. This pattern broke down when males were given access to already-amplectant male-female pairs： males of all body sizes readily attempted amplexus with the pair, with no size discrimination. An amplectant pair provides a larger visual stimulus, and prolonged amplexus provides a strong cue for sex iden- tification （one of the individuals involved is almost certainly a female）. Thus, a male cane toad＇s body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs

关键词： Mating systems Size-assortative mating large-male advantage Anurans Invasive species

From common gardens to candidate genes:an elegant case of homoploid hybrid speciation

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Molecular Plant 2021年第2期14卷 200-201页

作者： gregory l.Owens Department of Biology University of VictoriaVictoriaBCCanada

Homoploid hybrid speciation(HHS),where genetic contributions from two species combine to produce a third species without a change in pioidy,remains an intriguing and enigmatic evolutionary *** studies in the past decade have shown that introgression and admixture between species is common,and yet well documented cases of HHS remain rare(Schumer et al.,2014;Marques et al.,2019).This strikes at a key feature of HHS;it is a far higher bar to prove that hybridization was critical for speciation than it is to show that introgression *** former requires us to know how reproductive isolation(RI)is achieved,identify hybrid ancestry,and definitively link hybrid ancestry with reproductive *** this in mind,the work by Wang et al.(2020)fully documenting a case of HHS is particularly impressive in terms of both the scope and clarity of the results.

关键词： al. combine intro

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

High Altitude Frogs (Rana kukonoris) Adopt a Diversified Bethedging Strategy in the Face of Environmental Unpredictability

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Asian Herpetological Research 2018年第1期9卷 43-49页

作者： Wei CHEN liqing PENG lichun JIANG David A.PIKE Christopher R.FRIESEN gregory brown Ecological Security and Protection Key laboratory of Sichuan Province Mianyang Normal University Department of Biology Rhodes College School of life and Environmental Sciences University of Sydney

Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environments, but empirical field evidence from Asia is scarce. Here we tested this hypothesis by exploring spatial patterns in egg size along an altitudinal gradient in a frog species （Rana kukunoris） inhabiting the Tibetan Plateau. Within-clutch variability in egg size increased as the environment became variable （e.g., lower mean monthly temperature and mean monthly rainfall at higher altitudes）, and populations in environments with more unpredictable rainfall produced eggs that were smaller and more variable in size. We provide support for a diversified bet-hedging strategy in high-altitude environments, which experience dynamic weather patterns and therefore are of unpredictable environmental quality. This strategy may be an adaptive response to lower environmental quality and higher unpredictable environmental variance. Such a strategy should increase the likelihood of breeding success and maximize maternal lifetime fitness by producing offspring that are adapted to current environmental conditions. We speculate that in high-altitude environments prone to physical disturbance, breeding females are unable to consistently produce the optimal egg size due to physiological constraints imposed by environmental conditions （e.g., duration of the active season, food availability）. Species and populations whose breeding strategies are adapted to cope with uncertain environmental conditions by adjusting offspring size and therefore quality show a remarkable degree of ability to cope with future climatic changes.

关键词： altitude bet-hedging strategy environmental quality egg size within-clutch variation unpredictable environment

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Alteration in immune function in patients with fatty liver disease

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Hepatoma Research 2022年第1期8卷 363-375页

作者： Stephanie N.gregory Shruthi R.Perati Zachary J.brown Department of Surgery Rutgers Robert Wood Johnson Medical SchoolNew BrunswickNJ 08901USA Division of Surgical Oncology Department of SurgeryThe Ohio State University Wexner Medical CenterColumbusOH 43210USA

Nonalcoholic fatty liver disease(NAFlD)is a disease spectrum that spans simple steatosis,fibrosis,and ultimately cirrhosis,and is a leading cause of chronic liver disease *** severe variant of NAFlD,non-alcoholic steatohepatitis(NASH),is characterized by triglyceride accumulation within hepatocytes and the subsequent inflammatory pathway activation,ultimately progressing to cirrhosis in 10%-20%of *** is a known major risk factor for the development of hepatocellular carcinoma(HCC),and there is emerging data demonstrating the impact of NASH on immune subsets and the tumor microenvironment that may influence therapeutic *** review describes the various ways in which the immune system is altered in patients with *** innate immune system in NASH shows alterations in dendritic and Kupffer cells,impaired cytotoxicity of Natural Killer cells,and an accumulation of ***,there is emerging evidence emphasizing the role of the adaptive immune system in the development and progression of NASH,seen in the alteration of B-cells,T-cells,and NKT *** to the complex interplay of the immune system in NAFlD/NASH and its progression to HCC,many current treatments focus on targeting immune cells for HCC ***,immune checkpoint inhibitors such as atezolizumab and bevacizumab have been approved as first-line therapy for unresectable *** an emerging field of research,further studies and clinical trials are needed to understand the complex interface of NASH,HCC and the immune response.

关键词： Non-alcoholic steatohepatitis nonalcoholic fatty liver disease steatohepatitis immunology hepatocellular carcinoma

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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