| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Ederth, Thomas, et al.
(författare)
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Anomalous settlement behavior of Ulva linza zoospores on cationic oligopeptide surfaces
- 2008
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Ingår i: Biofouling (Print). - : Informa UK Limited. - 0892-7014 .- 1029-2454. ; 24:4, s. 303-312
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Tidskriftsartikel (refereegranskat)abstract
- Identification of settlement cues for marine fouling organisms opens up new strategies and methods for biofouling prevention, and enables the development of more effective antifouling materials. To this end, the settlement behaviour of zoospores of the green alga Ulva linza onto cationic oligopeptide self-assembled monolayers (SAMs) has been investigated. The spores interact strongly with lysine- and arginine-rich SAMs, and their settlement appears to be stimulated by these surfaces. Of particular interest is an arginine-rich oligopeptide, which is effective in attracting spores to the surface, but in a way which leaves a large fraction of the settled spores attached to the surface in an anomalous fashion. These 'pseudo-settled' spores are relatively easily detached from the surface and do not undergo the full range of cellular responses associated with normal commitment to settlement. This is a hitherto undocumented mode of settlement, and surface dilution of the arginine-rich peptide with a neutral triglycine peptide demonstrates that both normal and anomalous settlement is proportional to the surface density of the arginine-rich peptide. The settlement experiments are complemented with physical studies of the oligopeptide SAMs, before and after extended immersion in artificial seawater, using infrared spectroscopy, null ellipsometry and contact angle measurements.
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| 3. |
- Ederth, Thomas, et al.
(författare)
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Interactions of Zoospores of Ulva linza with Arginine-Rich Oligopeptide Monolayers
- 2009
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Ingår i: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 25:16, s. 9375-9383
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Tidskriftsartikel (refereegranskat)abstract
- We recently reported oil the strong interactions of zoospores of the green alga, Ulva linza with all arginine-rich oligopeptide self-assembled monolayer (SAM) [Biofouling 2008, 24, 303-312], where the arginine-rich peptide induced not only high spore settlement, but also a form of abnormal settlement, or "pseudo-settlement", whereby it proportion of spores do not go through the normal process of surface exploration, adhesive exocytosis, and loss of flagella. Further. it was demonstrated that both the total number of settled spores and the fraction of pseudosettled spores were related to the surface density of the arginine-rich peptide. Here we present a further investigation of the interactions of zoospores of ulva with a set of oligomeric, de nom designed, arginine-rich peptides, specifically aimed to test the effect of peptide primary structure on the interaction. Via variations in the peptide length and by permutations in the amino acid sequences, we gain further insight into the spore-surface interactions. The interpretation of the biological assays is supported by physicochemical characterization of the SAMs using infrared spectroscopy, ellipsometry, and contact angle measurement. Results confirm the importance of arginine residues for the anomalous pseudosettlement, and we found that settlement is modulated by variations in both the total length and peptide primary structure. To elucidate the Causes of the anomalous settlement and the possible relation to peptide-membrane interactions, we also compared the settlement of the "naked" zoospores of Ulva(which present it lipoprotein membrane to the exterior without a discrete polysaccharide cell wall), with the settlement of diatoms (unicellular algae that are surrounded by it silica cell wall), onto the peptide SAMs. Cationic SAMs do not notably affect settlement (attachment), adhesion strength, or viability of diatom cells, Suggesting that the effect of the peptides on zoospores of Ulva is mediated via specific peptide-membrane interactions.
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| 4. |
- Wang, Zhaohui, et al.
(författare)
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Regulation of muscle differentiation and survival by Acheron.
- 2009
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Ingår i: Mechanisms of Development. - : Elsevier BV. - 0925-4773 .- 1872-6356. ; 126:8-9, s. 700-9
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Tidskriftsartikel (refereegranskat)abstract
- Acheron (Achn), a phylogenetically-conserved member of the Lupus antigen family of RNA binding proteins, was initially identified as a novel cell death-associated gene from the intersegmental muscles of the tobacco hawkmoth Manduca sexta. C(2)C(12) cells are a standard model for the study of myogenesis. When deprived of growth factors, these cells can be induced to: form multinucleated myotubes, arrest as quiescent satellite-like reserve cells, or undergo apoptosis. Achn expression is induced in myoblasts that form myotubes and acts upstream of the muscle specific transcription factor MyoD. Forced expression of ectopic Achn resulted in the formation of larger myotubes and massive reserve cell death relative to controls. Conversely, dominant-negative or antisense Achn blocked myotube formation following loss of growth factors, suggesting that Achn plays an essential, permissive role in myogenesis. Studies in zebrafish embryos support this hypothesis. Reduction of Achn with antisense morpholinos led to muscle fiber loss and an increase in the number of surviving cells in the somites, while ectopic Achn enhanced muscle fiber formation and reduced cell numbers. These results display a crucial evolutionarily conserved role for Achn in myogenesis and suggest that it plays key roles in the processes of differentiation and self-renewal.
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| 5. |
- Zhang, Xia, 1980, et al.
(författare)
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Design of 50-70 GHz Planar Wideband Bandpass Filter on Liquid Crystal Polymer Substrate
- 2009
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Ingår i: Journal of Infrared, Millimeter, and Terahertz Waves. - : Springer Science and Business Media LLC. - 1866-6892 .- 1866-6906. ; 30:2, s. 183-189
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, the authors propose a novel and compact 50-70 GHz planar microstrip bandpass filter, possessing sharp-rejection, low insertion-loss and wide-band characteristics, based on Liquid Crystal Polymer (LCP) substrates. The filter is fabricated on LCP substrates by using standard processing technologies. The proposed filter exhibits a return loss level better than 10 dB, an insertion loss of 5 dB and a 3-dB bandwidth of 30%. The measured and simulated results show good agreement, proving that LCPs are potential and very promising materials for flexible millimeter-wave substrate applications.
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| 6. |
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