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Publication Quantum lie algebra solitons(IOP Publishing, 2013-11-29) Zuevsky, AlexanderWe construct a special type of quantum soliton solutions for quantized affine Toda models. The elements of the principal Heisenberg subalgebra in the affinised quantum Lie algebra are found. Their eigenoperators inside the quantized universal enveloping algebra for an affine Lie algebra are constructed to generate quantum soliton solutions.Publication Hopf algebra structure of continual virasoro algebra deformations(IOP Publishing, 2013-01-28) Zuevsky, AlexanderThe Hopf algebra structure of a few parametric deformations of the continual Virasoro algebra is proven.Publication U-q((G) over cap) Heisenberg families(Informa UK Limited, 2011-01-01) ZUEVSKY, A.We explicitly describe Heisenberg families of elements in an arbitrary grading subspaces of the quantized universal enveloping algebra U-q((G) over cap) of an affine Kac-Moody algebra (G) over cap in the Drinfeld formulation.Publication Catastrophic thinning of dielectric elastomers(American Physical Society (APS), 2017-02-15) Zurlo, G.; Destrade, M.; DeTommasi, D.; Puglisi, G.We provide an energetic insight into the catastrophic nature of thinning instability in soft electroactive elastomers. This phenomenon is a major obstacle to the development of giant actuators, yet it is neither completely understood nor modeled accurately. In excellent agreement with experiments, we give a simple formula to predict the critical voltages for instability patterns; we model their shape and show that reversible (elastic) equilibrium is impossible beyond their onset. Our derivation is fully analytical, does not require finite element simulations, and can be extended to include prestretch and various material models.Publication Printing non-euclidean solids(American Physical Society (APS), 2017-07-26) Zurlo, Giuseppe; Truskinovsky, LevGeometrically frustrated solids with a non-Euclidean reference metric are ubiquitous in biology and are becoming increasingly relevant in technological applications. Often they acquire a targeted configuration of incompatibility through the surface accretion of mass as in tree growth or dam construction. We use the mechanics of incompatible surface growth to show that geometrical frustration developing during deposition can be fine-tuned to ensure a particular behavior of the system in physiological (or working) conditions. As an illustration, we obtain an explicit 3D printing protocol for arteries, which guarantees stress uniformity under inhomogeneous loading, and for explosive plants, allowing a complete release of residual elastic energy with a single cut. Interestingly, in both cases reaching the physiological target requires the incompatibility to have a topological (global) component.Publication Persistence and stationary distribution of a stochastic predator-prey model under regime switching(American Institute of Mathematical Sciences (AIMS), 2017-02-01) Zu, Li; Jiang, Daqing; O'Regan, DonalTaking both white noise and colored environment noise into account, a predator-prey model is proposed. In this paper, our main aim is to study the stationary distribution of the solution and obtain the threshold between persistence in mean and the extinction of the stochastic system with regime switching. Some simulation figures are presented to support the analytical findings.Publication Stochastic permanence, stationary distribution and extinction of a single-species nonlinear diffusion system with random perturbation(Hindawi Limited, 2014-01-01) Zu, Li; Jiang, Daqing; O’Regan, DonalWe analyze the influence of stochastic perturbations on a single-species logistic model with the population's nonlinear diffusion among.. patches. First, we show that this system has a unique positive solution. Then we obtain sufficient conditions for stochastic permanence and persistence in mean, stationary distribution, and extinction. Finally, we illustrate our conclusions through numerical simulation.Publication Ticks and tick-borne diseases in Ireland(Springer Nature, 2017-01-31) Zintl, Annetta; Moutailler, Sara; Stuart, Peter; Paredis, Linda; Dutraive, Justine; Gonzalez, Estelle; O’Connor, Jack; Devillers, Elodie; Good, Barbara; OMuireagain, Colm; De Waal, Theo; Morris, Fergal; Gray, JeremyThroughout Europe interest in tick-borne agents is increasing, particularly with regard to those that can cause human disease. The reason for this is the apparent rise in the incidence of many tick-borne diseases (TBD's). While there has never been a national survey of ticks or TBD's in Ireland, the trend here appears to be the reverse with a decline in the incidence of some agents seemingly associated with decreasing tick numbers particularly on agricultural land. In the absence of robust baseline data, however, this development cannot be confirmed. This review collates the limited information available from several dated published records on tick species and a small number of studies focused on certain TBD's. Some pilot data on tick density and TBD agents collected in 2016 are also presented. The aim is to explore the particular situation in Ireland with regard to ticks and TBD's and to provide a reference for future workers in the field.Publication Overexpression of wnt5a in mouse epidermis causes no psoriasis phenotype but an impairment of hair follicle anagen development(Wiley-Blackwell, 2014-10-10) Zhu, Xuming; Wu, Yumei; Huang, Sixia; Chen, Yingwei; Tao, Yixin; Wang, Yushu; He, Shigang; Shen, Sanbing; Wu, Ji; Guo, Xizhi; Li, Baojie; He, Lin; Ma, GangIncreased Wnt5a expression has been observed in psoriatic plaques. However, whether Wnt5a overexpression directly causes psoriasis is unknown. In this study, we generated transgenic (TG) mice with epidermal Wnt5a overexpression under the control of the human K14 promoter. The skin of Wnt5a TG mice was not psoriatic, but characterized with normal proliferation and homeostasis of epidermis. Instead, these TG mice displayed impaired hair follicle transition from telogen to anagen, most likely due to impaired canonical Wnt signalling. These results suggest that increased Wnt5a expression alone is inadequate to induce psoriasis in the skin and possible involvement of Wnt5a in hair follicle cycling.Publication A general framework for representing, reasoning and querying with annotated semantic web data(Elsevier BV, 2012-03-01) Zimmermann, Antoine; Lopes, Nuno; Polleres, Axel; Straccia, UmbertoPublication Constitutive activation of ectodermal β-catenin induces ectopic outgrowths at various positions in mouse embryo and affects abdominal ventral body wall closure(Public Library of Science (PLoS), 2014-03-19) Zhu, Xuming; Huang, Sixia; Zhang, Lingling; Wu, Yumei; Chen, Yingwei; Tao, Yixin; Wang, Yushu; He, Shigang; Shen, Sanbing; Wu, Ji; Li, Baojie; Guo, Xizhi; He, Lin; Ma, GangVertebrate limbs originate from the lateral plate mesoderm (LPM) and the overlying ectoderm. While normal limb formation in defined regions has been well studied, the question of whether other positions retain limb-forming potential has not been fully investigated in mice. By ectopically activating beta-catenin in the ectoderm with Msx2-cre, we observed that local tissue outgrowths were induced, which either progressed into limb-like structure within the inter-limb flank or formed extra tissues in other parts of the mouse embryo. In the presumptive abdominal region of severely affected embryos, ectopic limb formation was coupled with impaired abdominal ventral body wall (AVBW) closure, which indicates the existence of a potential counterbalance of limb formation and AVBW closure. At the molecular level, constitutive beta-catenin activation was sufficient to trigger, but insufficient to maintain the ectopic expression of a putative limb-inducing factor, Fgf8, in the ectoderm. These findings provide new insight into the mechanism of limb formation and AVBW closure, and the crosstalk between the Wnt/beta-catenin pathway and Fgf signal.Publication A comprehensive experimental and modeling study of isobutene oxidation(Elsevier BV, 2016-05-01) Zhou, Chong-Wen; Li, Yang; O'Connor, Eoin; Somers, Kieran P.; Thion, Sébastien; Keesee, Charles; Mathieu, Olivier; Petersen, Eric L.; DeVerter, Trent A.; Oehlschlaeger, Matthew A.; Kukkadapu, Goutham; Sung, Chih-Jen; Alrefae, Majed; Khaled, Fathi; Farooq, Aamir; Dirrenberger, Patricia; Glaude, Pierre-Alexandre; Battin-Leclerc, Frédérique; Santner, Jeffrey; Ju, Yiguang; Held, Timothy; Haas, Francis M.; Dryer, Frederick L.; Curran, Henry J.Publication Cyclic brightening in the short-period wz sge-type cataclysmic variable sdss j080434.20+510349.2(EDP Sciences, 2008-05-22) Zharikov, S. V.; Tovmassian, G. H.; Neustroev, V. V.; Michel, R.; Zurita, C.; Echevarría, J.; Bikmaev, I. F.; Pavlenko, E. P.; Jeon, Y.-B.; Valyavin, G. G.; Aviles, A.Aims. We observed a new cataclysmic variable (CV) SDSS J080434.20+510349.2 to study the origin of long-term variability found in its light curve. Methods. Multi-longitude, time-resolved, photometric observations were acquired to analyze this uncommon behavior, which has been found in two newly discovered CVs. Results. This study of SDSS J080434.20+510349.2 concerns primarily the understanding of the nature of the observed, double-humped, light curve and its relation to a cyclic brightening that occurs during quiescence. The observations were obtained early in 2007, when the object was at about V similar to 17.1, about 0.4 mag brighter than the pre-outburst magnitude. The light curve shows a sinusoidal variability with an amplitude of about 0.07 mag and a periodicity of 42.48 min, which is half of the orbital period of the system. We observed in addition two "mini-outbursts" of the system of up to 0.6 mag, which have a duration of about 4 days each. The "mini-outburst" has a symmetric profile and is repeated in approximately every 32 days. Subsequent monitoring of the system shows a cyclical behavior of such "mini-outbursts" with a similar recurrence period. The origin of the double-humped light curve and the periodic brightening is discussed in the light of the evolutionary state of SDSS J080434.20+510349.2.Publication Biological study of the angiogenesis inhibitor n-(8-(3-ethynylphenoxy)octyl-1-deoxynojirimycin(Wiley-Blackwell, 2010-06-01) Zhao, Yunxue; Zhou, Ying; O’ Boyle, Kathy M.; Murphy, Paul V.The alpha-glucosidase inhibitors N-methyl-1-deoxynojirimycin (MDNJ) and castanospermine have been shown to inhibit angiogenesis. A hybrid of 1-deoxynojirimycin (DNJ) and an aryl-1,2,3-triazole, which inhibits both an alpha-glucosidase and methionine aminopeptidase-2 (MetAP2), displayed properties associated with inhibition of angiogenesis (Bioorg. Med. Chem., 16, 2008, 6333-7). The biological evaluation of a structural analogue N-(8-(3-ethynylphenoxy)octyl-1-deoxynojirimycin is described herein. Although this alkyne derivative did not inhibit MetAP2, it inhibited a bacterial alpha-glucosidase, altered bovine aortic endothelial cell (BAEC) surface oligosaccharide expression and inhibited BAEC proliferation by inducing G1 phase cell cycle arrest. Experiments showed G1 arrest was attributable to the alpha-glucosidase inhibitor inducing an increase in p27Kip1 expression and high phosphorylation of ERK1/2 without a reduction in cyclin D1. The DNJ derivative (0.1 mm) prevented capillary tube formation from bovine aortic endothelial cells, whereas DNJ or other analogues were unable to inhibit tube formation at the same concentration. Stress fiber assembly in bovine aortic endothelial cells was abolished, and BAEC migration was inhibited indicating the inhibition of tube formation by this derivative is partially a result of a reduction in cell motility. The agent also caused a reduction in secretion of MMP-2 from bovine aortic endothelial cells. Therefore, the new alpha-glucosidase inhibitor has a different mechanism by which it inhibits angiogenesis in vitro when compared with deoxynojirimycin, the deoxynojirimycin -triazole hybrid, N-methyl-1-deoxynojirimycin and castanospermine.Publication Pb isotope compositions of detrital k-feldspar grains in the upper-middle yangtze river system: implications for sediment provenance and drainage evolution(Wiley-Blackwell, 2014-07-01) Zhang, Zengjie; Tyrrell, Shane; Li, Chang'an; Daly, J. Stephen; Sun, Xilin; Li, QiwenThe upper-middle Yangtze River drains the Qiangtang Block, the Songpan-Ganzi, the Yangtze Craton, and the Qinling-Dabie orogenic belt. These tectonic units have been shown to have heterogeneous Pb isotopic compositions, which allow this isotope system to be used as a sediment provenance tool. In this study we have employed laser ablation multiple collector inductively coupled plasma mass spectrometry (LA-MC-ICPMS) to measure Pb isotope compositions of sand-sized K-feldspar grains from the upper-middle Yangtze River. Data are presented from four major tributaries: Yalongjiang, Minjiang, Jialingjiang, and Hanjiang, as well as from the main Yangtze River near Yichang. A portion of K-feldspar grains in the Yalongjiang shows an ultraradiogenic character (Pb-206/Pb-204 > 20), which is unique in the upper-middle Yangtze. Moreover, these ultraradiogenic grains were transported as far as Yichang, just downstream from the Three Gorges, suggesting that the Pb-in-K-feldspar method could be applied to the sediments within the Jianghan Basin to date the formation of the Three Gorges. Pb isotopic data from Yichang indicate that erosion in the Longmen Shan and neighboring regions is more important than the Jinshajiang in supplying sediment. The grains in Hanoi Basin have little overlap with the Songpan-Ganzi, but show a good match with the Yangtze Craton in its range of lower 206Pb/204Pb ratios. These observations support the idea that the "Middle Yangtze'' used to be a tributary of the paleo-Red River and that there has been no drainage linking the SongpanGanzi and the Red River since the Eocene.Publication Controlled multi-vinyl monomer homopolymerization through vinyl oligomer combination as a universal approach to hyperbranched architectures(Springer Nature, 2013-05-21) Zhao, Tianyu; Zheng, Yu; Poly, Julien; Wang, WenxinThe three-dimensional structures of hyperbranched materials have made them attractive in many important applications. However, the preparation of hyperbranched materials remains challenging. The hyperbranched materials from addition polymerization have gained attention, but are still confined to only a low level of branching and often low yield. Moreover, the complication of synthesis only allows a few specialized monomers and inimers to be used. Here we report a 'Vinyl Oligomer Combination' strategy; a versatile approach that overcomes these difficulties and allows facile synthesis of highly branched polymeric materials from readily available multi-vinyl monomers, which have long been considered as formidable starting materials in addition polymerization. We report the alteration of the growth manner of polymerization by controlling the kinetic chain length, together with the manipulation of chain growth conditions, to achieve veritable hyperbranched materials, which possess nearly 70% branch ratios as well as numerous vinyl functional groups.Publication Contamination and spatial variation of heavy metals in the soil-rice system in Nanxun county, southeastern China(MDPI AG, 2015-01-28) Zhao, Keli; Fu, Weijun; Ye, Zhengqian; Zhang, ChaoshengThere is an increasing concern about heavy metal contamination in farmland in China and worldwide. In order to reveal the spatial features of heavy metals in the soil-rice system, soil and rice samples were collected from Nanxun, Southeastern China. Compared with the guideline values, elevated concentrations of heavy metals in soils were observed, while heavy metals in rice still remained at a safe level. Heavy metals in soils and rice had moderate to strong spatial dependence (nugget/sill ratios: 13.2% to 49.9%). The spatial distribution of copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) in soils illustrated that their high concentrations were located in the southeast part. The high concentrations of cadmium (Cd) in soils were observed in the northeast part. The accumulation of all the studied metals is related to the long-term application of agrochemicals and industrial activities. Heavy metals in rice showed different spatial distribution patterns. Cross-correlograms were produced to quantitatively determine the spatial correlation between soil properties and heavy metals composition in rice. The pH and soil organic matter had significant spatial correlations with the concentration of heavy metals in rice. Most of the selected variables had clear spatial correlation ranges for heavy metals in rice, which could be further applied to divide agricultural management zones.Publication Characterization and seasonal variations of levoglucosan in fine particulate matter in xi’an, china(Informa UK Limited, 2014-10-20) Zhang, Ting; Cao, Jun-Ji; Chow, Judith C.; Shen, Zhen-Xing; Ho, Kin-Fai; Ho, Steven Sai Hang; Liu, Sui-Xin; Han, Yong-Ming; Watson, John G.; Wang, Ge-Hui; Huang, Ru-JinPM2.5 (particulate matter with an aerodynamic diameter <2.5 mu m) samples (n = 58) collected every sixth day in Xi'an, China, from 5 July 2008 to 27 June 2009 are analyzed for levoglucosan (1,6-anhydro-beta-d-glucopyranose) to evaluate the impacts of biomass combustion on ambient concentrations. Twenty-four-hour levoglucosan concentrations displayed clear summer minima and winter maxima that ranged from 46 to 1889 ng m(-3), with an average of 428 +/- 399 ng m(-3). Besides agricultural burning, biomass/biofuel combustion for household heating with straws and branches appears to be of regional importance during the heating season in northwestern China. Good correlations (0.70 < R < 0.91) were found between levoglucosan relative to water-soluble K+, Cl-, organic carbon (OC), elemental carbon (EC), and glyoxal. The highest levoglucosan/OC ratio of 2.3% was found in winter, followed by autumn (1.5%). Biomass burning contributed to 5.1-43.8% of OC (with an average of 17.6 +/- 8.4%). Implications: PM2.5 levoglucosan concentrations and the correlation between levoglucosan relative to other compounds during four seasons in Xi'an showed that the influence of biomass burning is maximum during the residential heating season (winter), although some important influences may be detected in spring (field preparation burnings) and autumn (corn stalks and wheat straw burning, fallen dead leaves burning) at Xi'an and surrounding areas. Household heating with biomass during winter was quite widespread in Guanzhong Plain. Therefore, the control of biomass/biofuel combustion could be an effective method to reduce pollutant emission on a regional scale.Publication Leakage inductance calculation for planar transformers with a magnetic shunt(Institute of Electrical and Electronics Engineers (IEEE), 2014-11-01) Zhang, Jun; Ouyang, Ziwei; Duffy, Maeve C.; Andersen, Michael A. E.; Hurley, William GerardThe magnetic shunt is generally inserted in a planar transformer to increase the leakage inductance, which can be utilized as the series inductor in resonant circuits such as the LLC resonant converter. This paper presents a calculation methodology for the leakage inductance of the transformer with a magnetic shunt by means of the stored magnetic energy in the primary and secondary sides of the transformer using the magnetomotive force (MMF) variation method, as well as the stored energy in the shunt based on the reluctance model. The detailed calculation method is described. Both the finite-element analysis simulation and the experimental results have proven the validity of the proposed calculation method for leakage inductance.Publication Modification of histones by sugar β-n-acetylglucosamine (glcnac) occurs on multiple residues, including histone h3 serine 10, and is cell cycle-regulated(American Society for Biochemistry & Molecular Biology (ASBMB), 2011-09-06) Zhang, Suisheng; Roche, Kevin; Nasheuer, Heinz-Peter; Lowndes, Noel FrancisThe monosaccharide, beta-N-acetylglucosamine (GlcNAc), can be added to the hydroxyl group of either serines or threonines to generate an O-linked beta-N-acetylglucosamine (O-GlcNAc) residue (Love, D. C., and Hanover, J. A. (2005) Sci. STKE 2005 312, 1-14; Hart, G. W., Housley, M. P., and Slawson, C. (2007) Nature 446, 1017-1022). This post-translational protein modification, termed O-GlcNAcylation, is reversible, analogous to phosphorylation, and has been implicated in many cellular processes. Here, we present evidence that in human cells all four core histones of the nucleosome are substrates for this glycosylation in the relative abundance H3, H4/H2B, and H2A. Increasing the intracellular level of UDP-GlcNAc, the nucleotide sugar donor substrate for O-GlcNAcylation enhanced histone O-GlcNAcylation and partially suppressed phosphorylation of histone H3 at serine 10 (H3S10ph). Expression of recombinant H3.3 harboring an S10A mutation abrogated histone H3 O-GlcNAcylation relative to its wild-type version, consistent with H3S10 being a site of histone O-GlcNAcylation (H3S10glc). Moreover, O-GlcNAcylated histones were lost from H3S10ph immunoprecipitates, whereas immunoprecipitation of either H3K4me3 or H3K9me3 (active or inactive histone marks, respectively) resulted in co-immunoprecipitation of O-GlcNAcylated histones. We also examined histone O-GlcNAcylation during cell cycle progression. Histone O-GlcNAcylation is high in G(1) cells, declines throughout the S phase, increases again during late S/early G(2), and persists through late G(2) and mitosis. Thus, O-GlcNAcylation is a novel histone post-translational modification regulating chromatin conformation during transcription and cell cycle progression.