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Heterogeneous activity causes a nonlinear increase in the group energy use of ant workers isolated from queen and brood

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Insect Science 2018年第3期25卷 487-498页

作者： nolan ferral Kyara Holloway Mingzhong Li Zhaozheng Yin Chen Hou Department of Biological Sciences Missouri University of Science and Technology Rolla Missouri USA Department of Computer Sciences Missouri University of Science and Technology Rolla Missouri USA

Increasing evidence has shown that the energy use of ant colonies increases sublinearly with colony size so that large colonies consume less per capita energy than small colonies. It has been postulated that social environment （e.g., in the presence of queen and brood） is critical for the sublinear group energetics, and a few studies of ant workers isolated from queens and brood observed linear relationships between group energetics and size. In this paper, we hypothesize that the sublinear energetics arise from the heterogeneity of activity in ant groups, that is, large groups have relatively more inactive members than small groups. We further hypothesize that the energy use of ant worker groups that are allowed to move freely increases more slowly than the group size even if they are isolated from queen and brood. Previous studies only provided indirect evidence for these hypotheses due to technical difficulties. In this study, we applied the automated behavioral monitoring and respirometry simultaneously on isolated worker groups for long time periods, and analyzed the image with the state-of-the-art algorithms. Our results show that when activity was not confined, large groups had lower per capita energy use, a lower percentage of active members, and lower average walking speed than small groups; while locomotion was confined, however, the per capita energy use was a constant regardless of the group size. The quantitative analysis shows a direct link between variation in group energy use and the activity level of ant workers when isolated from queen and brood.

关键词： activity energetics image analysis long term scaling simultaneous

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Maintenance of stem cell self-renewal by sex chromosomal zincfinger transcription factors

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World Journal of Methodology 2024年第4期14卷 23-29页

作者： Katsuhiro Kita Celine Morkos Kathleen nolan Department of Biology St.Francis CollegeBrooklynNY 11201United States

In this Editorial review,we would like to focus on a very recent discovery showing the global autosomal gene regulation by Y-and inactivated X-chromosomal transcription factors,zinc finger gene on the Y chromosome(ZFY)and zinc finger protein X-linked(ZFX).ZFX and ZFY are both zinc-finger proteins that encode general transcription factors abundant in hematopoietic and embryonic stem *** both proteins are homologs,interestingly,the regulation of self-renewal by these transcriptional factors is almost exclusive to *** fact implies that there are some differential roles between ZFX and ZFY in regulating the maintenance of self-renewal activity in stem *** the maintenance of stemness,ZFX overexpression or mutations may be linked to certain *** cancers and stem cells are double-edged swords,there is no study showing the link between ZFX activity and the ***,stemness or cancers with ZFX may be linked to other molecules,such as Oct4,Sox2,Klf4,and *** on very recent studies and a few lines of evidence in the past decade,it appears that the ZFX is linked to the canonical Wnt signaling,which is one possible mechanism to explain the role of ZFX in the self-renewal of stem cells.

关键词： ZFX ZFY Self-renewal Stem cell Sex chromosome regulators

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Impact of surface hydroxylation in MgO-/SnO-nanocluster modified TiO_2 anatase(101) composites on visible light absorption, charge separation and reducibility

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Chinese Chemical Letters 2018年第6期29卷 757-764页

作者： Stephen Rhatigan Michael nolan Tyndall National Institute University College Cork

Surface modification with metal oxide nanoclusters has emerged as a candidate for the enhancement of the photocatalytic activity of titanium dioxide. An increase in visible light absorption and the suppression of charge carrier recombination are necessary to improve the efficiency. We have studied Mg4O4 and Sn4O4 nanoclusters modifying the（101） surface of anatase TiO2 using density functional theory corrected for on-site Coulomb interactions（DFT ＋ U）. Such studies typically focus on the pristine surface, free of the point defects and surface hydroxyls present in real surfaces. We have also examined the impact of partial hydroxylation of the anatase surface on a variety of outcomes such as nanocluster adsorption, light absorption, charge separation and reducibility. Our results indicate that the modifiers adsorb strongly at the surface, irrespective of the presence of hydroxyl groups, and that modification extends light absorption into the visible range while enhancing UV activity. Our model for the excited state of the heterostructures demonstrates that photoexcited electrons and holes are separated onto the TiO2 surface and metal oxide nanocluster respectively. Comparisons with bare TiO2 and other TiO2-based photocatalyst materials are presented throughout.

关键词： Photocatalyst Titania Visible-light absorption Surface modification Charge separation Surface hydroxylation Oxygen vacancy formation

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Testosterone treatment in older men： glass half empty or half full？

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Asian Journal of Andrology 2017年第5期19卷 512-514页

作者： Brendan J nolan Mathis Grossmann Department of Endocrinology Austin HealthHeidelberg Victoria 3084 Australia Department of Medicine University of Melbourne Austin HealthHeidelberg Victoria 3084 Australia

In a series of randomized controlled trials published in JAMA and JAMA Intern Med,US researchers have examined the effect of testosterone treatment in older men with testosterone levels 〈275 ng dl^-1 on coronary arte... 详细信息

关键词： ELDERLY-MEN HYPOGONADISM

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Dyeing of Polypropylene Fibers with Vat Dyes

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Journal of Donghua University(English Edition) 2006年第5期23卷 15-19页

作者：刘航 ETTERS J . nolan LEONAS Karen K Department of Textiles Merchandising & Interiors University of Georgia Athens Georgia 30605 USA

Polypropylene fibers have been extensively used in a variety of/products, including carpets and upholstery, due to their non-absorbency, good weather resistance, good resistance to macroorgamsms and so on. Because of their hydrophobic and highly crystalline nature, those well-established conventionai dyeing processes are difficult to apply to unmodified polypropylene. Colors of polypropylene fibers are primarily obtained by mass coloration which has the disadvantages of limited number of colors available and difficulties in inventory control due to the rapidly changing color needs of the market. In this paper, the use of vat dyes to dye polypropylene fabrics is investigated. Seventeen vat dyes were screened and factors influencing uptake of dyes by polypropylene fabrics were studied.

关键词： pol ypropylene vat dye leuco acid vat dye.

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Selection of overburden surface mining method in West Virginia by analytical hierarchy process

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International Journal of Coal Science & Technology 2014年第3期1卷 306-314页

作者： Timothy A.nolan Vladislav Kecojevic Department of Mining Engineering West Virginia UniversityMorgantownWVUSA

The broad objective of this research was to improve current surface mining practices and reduce negative environmental impact of overburden removal in West Virginia(WV).The specific objectives were to(i)compare conventional surface mining method(drilling,blasting,digging,and loading)to a surface miner(SM)method,and(ii)apply the analytical hierarchy process(AHP)to help select the optimal mining method based on production,cost and environmental *** design and the procedures used in this research involve five interrelated modules:(i)rock properties of overburden in WV,(ii)drilling and blasting,(iii)digging and loading,(iv)SM method,and(v)comparative analysis and selection of the optimal mining method by *** of this research indicate that application of SM method would yield higher cost of overburden removal than conventional mining methods in rocks with a high unconfined compressive strength and abrasivity.A significant advantage of SM method,where applicable,is the elimination of the negative environmental impacts associated with blasting.

关键词： Surface mining West Virginia Overburden Production rate Cost Environmental impact AHP model

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Multiple forest structural elements are needed to promote beetle biomass, diversity and abundance

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Forest Ecosystems 2022年第5期9卷 585-595页

作者： nolan J.Rappa Michael Staab Julian Frey Nathalie Winiger Alexandra-Maria Klein Nature Conservation and Landscape Ecology University of FreiburgTennenbacherstrasse 479106Freiburg im BreisgauGermany Ecological Networks Technical University DarmstadtSchnittspahnstrasse 364287DarmstadtGermany Forest Growth and Dendroecology University of FreiburgTennenbacherstrasse 479106Freiburg im BreisgauGermany Wildlife Ecology and Management University of FreiburgTennenbacherstrasse 479106Freiburg im BreisgauGermany

Background:Retention forestry is a management strategy aiming to mitigate biodiversity loss by retaining structural elements such as dead trees that would otherwise be *** we analyze the biomass,diversity and abundance among forest beetles collected using window traps on 1281-ha forest sites reflecting gradients in the amount of structural elements in southwestern ***:We found that beetle biomass increased with mean diameter at breast height(a measure of tree size),and decreased with stand structural *** of individual feeding guilds responded differently to forest structural elements,namely lying deadwood,understory complexity,tree basal area and stand structural *** family diversity increased with the effective number of layers,i.e.1-m forest strata occupied by vegetation assessed via terrestrial laser *** of feeding guilds responded to only elevation and share of deciduous *** composition in terms of biomass was structured by forest elements similar to biomass of individual feeding guilds,with the addition of lying *** differed from community composition in terms of abundance of feeding guilds,which was structured by primarily standing deadwood volume and share of deciduous ***:Our results show that biomass,diversity and abundance respond differently to forest structural *** suggests that the concurrent prioritization of multiple forest elements is needed to promote forest beetles,with more focus placed on the differing resource needs among feeding *** addition,retention strategies should also consider the varying responses of beetle biodiversity metrics when assessing the importance of forest structural elements.

关键词： Allometry Biodiversity Coleoptera Forest management Terrestrial laser scanning Window trap

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Transforming growth factor-β signaling in systemic sclerosis

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The Journal of Biomedical Research 2018年第1期32卷 3-12页

作者： nolan B.Ayers Chenming Sun Shi-You Chen Department of Physiology & Pharmacology University of Georgia

Systemic sclerosis（SSc） is a complex, multiorgan autoimmune disease of unknown etiology. Manifestation of the disease results from an interaction of three key pathologic features including irregularities of the antigen-specific immune system and the non-specific Immune system, resulting in autoantibody production, vascular endothelial activation of small blood vessels, and tissue fibrosis as a result of fibroblast dysfunction. Given the heterogeneity of clinical presentation of the disease, a lack of universal models has impeded adequate testing of potential therapies for SSc. Regardless, recent research has elucidated the roles of various ubiquitous molecular mechanisms that contribute to the clinical manifestation of the disease. Transforming growth factor β（TGF-β） has been identified as a regulator of pathological fibrogenesis in SSc. Various processes, including cell growth, apoptosis, cell differentiation, and extracellular matrix synthesis are regulated by TGF-β,a type of cytokine secreted by macrophages and many other cell types. Understanding the essential role TGF-β pathways play in the pathology of systemic sclerosis could provide a potential outlet for treatment and a better understanding of this severe disease.

关键词： systemic sclerosis transforming growth factor-β mechanism therapeutics

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An Approach to Quantify Endomembrane Dynamics in Pollen Utilizing Bioactive Chemicals

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Molecular Plant 2013年第4期6卷 1202-1213页

作者： nolan Ung Michelle Q. Brown Glenn R. Hicks Natasha V. Raikhel Center for Plant Cell Biology and Department of Botany and Plant Sciences University of California Riverside Riverside CA 92521 USA

Tip growth of pollen tubes and root hairs occurs via rapid polar growth. These rapidly elongating cells require tip-focused endomembrane trafficking for the deposition and recycling of proteins, membranes, and cell wall materials. Most of the image-based data published to date are subjective and non-quantified. Quantitative and com- parative descriptors of these highly dynamic processes have been a major challenge, but are highly desirable for genetic and chemical genomics approaches to dissect this biological network. To address this problem, we screened for small molecules that perturbed the localization of a marker for the Golgi Ras-like monomeric G-protein RAB2：GFP expressed in transgenic tobacco pollen. Semi-automated high-throughput imaging and image analysis resulted in the identifica- tion of novel compounds that altered pollen tube development and endomembrane trafficking. Six compounds that caused mislocalization and varying degrees of altered movement of RAB2：GFP-labeled endomembrane bodies were used to generate a training set of image data from which to quantify vesicle dynamics. The area, velocity, straightness, and intensity of each body were quantified using semi-automated image analysis tools revealing quantitative differences in the phenotype caused by each compound. A score was then given to each compound enabling quantitative comparisons between compounds. Our results demonstrate that image analysis can be used to quantitatively evaluate dynamic sub- cellular endomembrane phenotypes induced by bioactive chemicals, mutations, or other perturbing agents as part of a strategy to quantitatively dissect the endomembrane network.

关键词： endomembranes vesicle trafficking quantification pollen chemical biology.

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Local Anesthesia in Cataract Surgery-A Comparison of Different Methods

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眼科学报 1993年第1期9卷 21-22,20页

作者： nolan J Aziz M Ahmad M Shehata M Iqbal F Department of Ophthalmology University College hospital Galway IrelandDepartment of Ophthalmology University College hospital Galway IrelandDepartment of Ophthalmology University College hospital Galway IrelandDepartment of Ophthalmology University College hospital Galway IrelandDepartment of Ophthalmology University College hospital Galway Ireland

Seven groups of thirty patients undergoing cataract extraction under local anesthesia were each given different combinations of local anesthesia. These varied from a maximum approach using supra-orbital, infra-orbital and facial blocks with Hyalase, orbital compression and pre-operative Acetazolamide down to a minimum group receiving purely an infra- orbital and supra-orbital block with a Ugnocaine/Bupivacaine mixture. There was no significant difference in local analgesia or in the complication rates b...

关键词： Cararct surgery Anaesthesia.

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