| 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. |
- Aaron, F. D., et al.
(författare)
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Multi-leptons with high transverse momentum at HERA
- 2009
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Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479. ; :10
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Tidskriftsartikel (refereegranskat)abstract
- Events with at least two high transverse momentum leptons (electrons or muons) are studied using the H1 and ZEUS detectors at HERA with an integrated luminosity of 0.94 fb(-1). The observed numbers of events are in general agreement with the Standard Model predictions. Seven di- and tri-lepton events are observed in e(+)p collision data with a scalar sum of the lepton transverse momenta above 100 GeV while 1.94 +/- 0.17 events are expected. Such events are not observed in e(-)p collisions for which 1.19 +/- 0.12 are predicted. Total visible and differential di-electron and di-muon photoproduction cross sections are extracted in a restricted phase space dominated by photon-photon collisions.
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| 3. |
- Abat, E., et al.
(författare)
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Study of the response of the ATLAS central calorimeter to pions of energies from 3 to 9 GeV
- 2009
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002 .- 1872-9576. ; 607:2, s. 372-386
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Tidskriftsartikel (refereegranskat)abstract
- A fully instrumented slice of the ATLAS central detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. in this paper, the response of the central calorimeters to pions with energies in the range between 3 and 9 GeV is presented. The linearity and the resolution of the combined calorimetry (electromagnetic and hadronic calorimeters) was measured and compared to the prediction of a detector simulation program using the toolkit Geant 4. (C) 2009 Elsevier B.V. All rights reserved.
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| 4. |
- Abat, E., et al.
(författare)
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The ATLAS TRT end-cap detectors
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- The ATLAS TRT end-cap is a tracking drift chamber using 245,760 individual tubular drift tubes. It is a part of the TRT tracker which consist of the barrel and two end-caps. The TRT end-caps cover the forward and backward pseudo-rapidity region 1.0 < vertical bar eta vertical bar < 2.0, while the TRT barrel central eta region vertical bar eta vertical bar < 1.0. The TRT system provides a combination of continuous tracking with many measurements in individual drift tubes ( or straws) and of electron identification based on transition radiation from fibers or foils interleaved between the straws themselves. Along with other two sub-systems, namely the Pixel detector and Semi Conductor Tracker (SCT), the TRT constitutes the ATLAS Inner Detector. This paper describes the recently completed and installed TRT end-cap detectors, their design, assembly, integration and the acceptance tests applied during the construction.
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| 5. |
- Abat, E., et al.
(författare)
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The ATLAS Transition Radiation Tracker (TRT) proportional drift tube: design and performance
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:2
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Tidskriftsartikel (refereegranskat)abstract
- A straw proportional counter is the basic element of the ATLAS Transition Radiation Tracker (TRT). Its detailed properties as well as the main properties of a few TRT operating gas mixtures are described. Particular attention is paid to straw tube performance in high radiation conditions and to its operational stability.
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| 6. |
- Abat, E., et al.
(författare)
-
The ATLAS TRT barrel detector
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- The ATLAS TRT barrel is a tracking drift chamber using 52,544 individual tubular drift tubes. It is one part of the ATLAS Inner Detector, which consists of three sub-systems: the pixel detector spanning the radius range 4 to 20 cm, the semiconductor tracker (SCT) from 30 to 52 cm, and the transition radiation tracker ( TRT) from 56 to 108 cm. The TRT barrel covers the central pseudo-rapidity region |eta| < 1, while the TRT endcaps cover the forward and backward eta regions. These TRT systems provide a combination of continuous tracking with many measurements in individual drift tubes ( or straws) and of electron identification based on transition radiation from fibers or foils interleaved between the straws themselves. This paper describes the recently-completed construction of the TRT Barrel detector, including the quality control procedures used in the fabrication of the detector.
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| 7. |
- Abat, E., et al.
(författare)
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The ATLAS TRT electronics
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:6
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Tidskriftsartikel (refereegranskat)abstract
- The ATLAS inner detector consists of three sub-systems: the pixel detector spanning the radius range 4cm-20cm, the semiconductor tracker at radii from 30 to 52 cm, and the transition radiation tracker (TRT), tracking from 56 to 107 cm. The TRT provides a combination of continuous tracking with many projective measurements based on individual drift tubes (or straws) and of electron identification based on transition radiation from fibres or foils interleaved between the straws themselves. This paper describes the on and off detector electronics for the TRT as well as the TRT portion of the data acquisition (DAQ) system.
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| 8. |
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| 9. |
- Pham, M. K., et al.
(författare)
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A new Certified Reference Material for radionuclides in Irish sea sediment (IAEA-385)
- 2008
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Ingår i: APPLIED RADIATION AND ISOTOPES. - : Elsevier BV. - 1872-9800 .- 0969-8043. ; 66:11, s. 1711-1717
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Konferensbidrag (refereegranskat)abstract
- A new Certified Reference Material (CRM) for radionuclides in sediment (IAEA-385) is described and the results of the certification process are presented. Eleven radionuclides (K-40, Cs-137, Ra-226, Ra-228, Th-230, Th-232, U-234, U-238, Pu-238, Pu239+240 and Am-241) have been certified and information mass activities with 95% confidence intervals are given for seven other radionuclides (Sr-90, Pb-210(Po-210), U-235, Pu-239, Pu-240 and Pu-241). Results for less frequently reported radionuclides (Co-60, Tc-99, Cs-134, Eu-155, Ra-224 and Np-239) and information on some activity and mass ratios are also reported. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in sediment samples, for the development and validation of analytical methods and for training purposes. (C) 2008 IAEA. Published by Elsevier Ltd. All rights reserved.
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| 10. |
- Pham, M. K., et al.
(författare)
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Certified reference material for radionuclides in fish flesh sample IAEA-414 (mixed fish from the Irish Sea and North Sea)
- 2006
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Ingår i: Proceedings of the 15th International Conference on Radionuclide Metrology and its Applications (Applied Radiation and Isotopes). - Amsterdam : Elsevier BV. - 0969-8043 .- 1872-9800. ; 64:10-11, s. 1253-1259
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Konferensbidrag (refereegranskat)abstract
- A certified reference material (CRM) for radionuclides in fish sample IAEA-414 (mixed fish from the Irish Sea and North Seas) is described and the results of the certification process are presented. Nine radionuclides (K-40, Cs-137, Th-232, U-234, U-235, U-238, Pu-238, Pu239+240 and Am-241) were certified for this material. Information on massic activities with 95% confidence intervals is given for six other radionuclides (Sr-90, Pb-210(Po-210), Ra-226, Pu-239, Pu-240 Pu-241). Less frequently reported radionuclides (Tc-99, I-129, Th-228, Th-230 and Np-217) and information on some activity and mass ratios are also included. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in fish sample, for the development and validation of analytical methods and for training purposes. The material is available from IAEA, Vienna, in 100 g units.
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| 11. |
- Povinec, Pavel, et al.
(författare)
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Reference material for radionuclides in sediment. IAEA-384 (Fangataufa lagoon sediment).
- 2007
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Ingår i: Journal of Radioanalytical and Nuclear Chemistry. - Dordrecht : Springer. - 0236-5731 .- 1588-2780. ; 273:2, s. 383-393
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Tidskriftsartikel (refereegranskat)abstract
- A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units.
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| 12. |
- Cwetanski, P, et al.
(författare)
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Acceptance tests and criteria of the ATLAS transition radiation tracker
- 2005
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Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499. ; 52:6, s. 2911-2916
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Tidskriftsartikel (refereegranskat)abstract
- The Transition Radiation Tracker (TRT) sits at the outermost part of the ATLAS Inner Detector, encasing the Pixel Detector and the Semi-Conductor Tracker (SCT). The TRT combines charged particle track reconstruction with electron identification capability. This is achieved by layers of xenonfilled straw tubes with periodic radiator foils or fibers providing TR photon emission. The design and choice of materials have been optimized to cope with the harsh operating conditions at the LHC, which are expected to lead to an accumulated radiation dose of 10 Mrad and a neutron fluence of up to 2 . 10(14) n/cm(2) after ten years of operation. The TRT comprises a barrel containing 52 000 axial straws and two end-cap parts with 320 000 radial straws. The total of 420 000 electronic channels (two channels per barrel straw) allows continuous tracking with many projective measurements (more than 30 straw hits per track). The assembly of the barrel modules in the US has recently been completed, while the end-cap wheel construction in Russia has reached the 50% mark. After testing at the production sites and shipment to CERN, all modules and wheels undergo a series of quality and conformity measurements. These acceptance tests survey dimensions, wire tension, gas-tightness, high-voltage stability and gas-gain uniformity along each individual straw. This paper gives details on the acceptance criteria and measurement methods. An overview of the most important results obtained to-date is also given.
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| 13. |
- Ferwerda, Bart, et al.
(författare)
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Functional and genetic evidence that the Mal/TIRAP allele variant 180L has been selected by providing protection against septic shock.
- 2009
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 106:25, s. 10272-10277
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Tidskriftsartikel (refereegranskat)abstract
- Adequate responses by our innate immune system toward invading pathogens were of vital importance for surviving infections, especially before the antibiotic era. Recently, a polymorphism in Mal (Ser180Leu, TIRAP rs8177374), an important adaptor protein downstream of the Toll-like receptor (TLR) 2 and 4 pathways, has been described to provide protection against a broad range of infectious pathogens. We assessed the functional effects of this polymorphism in human experimental endotoxemia, and we demonstrate that individuals bearing the TIRAP 180L allele display an increased, innate immune response to TLR4 and TLR2 ligands, but not to TLR9 stimulation. This phenotype has been related to an increased resistance to infection. However, an overshoot in the release of proinflammatory cytokines by TIRAP 180L homozygous individuals suggests a scenario of balanced evolution. We have also investigated the worldwide distribution of the Ser180Leu polymorphism in 14 populations around the globe to correlate the genetic makeup of TIRAP with the local infectious pressures. Based on the immunological, clinical, and genetic data, we propose that this mutation might have been selected in West Eurasia during the early settlement of this region after the out-of-Africa migration of modern Homo sapiens. This combination of functional and genetic data provides unique insights to our understanding of the pathogenesis of sepsis.
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| 14. |
- Siegenthaler, MP, et al.
(författare)
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Mechanical reliability of the Jarvik 2000 Heart - Discussion
- 2006
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Ingår i: Annals of Thoracic Surgery. - : Elsevier BV. - 1552-6259 .- 0003-4975. ; 81:5, s. 1752-1759
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Tidskriftsartikel (refereegranskat)abstract
- Background. Device failure is a limitation of permanent mechanical circulatory support. We studied the mechanical reliability of the Jarvik 2000 Heart, an axial flow pump with ceramic bearings designed to provide more than 10 years' durability. Methods. The Jarvik 2000 Heart was implanted in 102 patients between April 2000 and December 2004. Eighty-three pumps with an abdominal driveline were implanted as a bridge-to-transplantation, and 19 with post-auricular power supply as lifetime therapy. Eighteen pumps were recovered intact after clinical use and run continuously on the bench to further assess durability. Results. No implantable component failure occurred either in patients or during bench testing. The cumulative pump run-time was 110 years: 59 years overall in vivo and 51 years in vitro. The mean support time for bridge-to-transplant recipients was 159 days, and for discharged lifetime-therapy recipients 551 days. Six recipients were supported moer than 2 years, with the longest ongoing approaching 5 years. External cables caused three system failures, with a 95% freedom from system failure at 4 years. Device malfunctions, related to external cables ( 9) and lack of a backup battery ( 1), caused no adverse consequences. Before introduction of noncorrosive, gold-plated stainless steel connectors, corrosion was observed on three connectors to the retroauricular power supply. Conclusions. The Jarvik 2000 Heart has had no implantable component failure. Meaningful durability data and failure mode can only be established by real-time testing in patients. The reliability and dependability of this device, in addition to the exchangeability of external components, give promise for long-term circulatory support in critically ill heart failure patients.
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| 15. |
- Adewumi, Oluseun, et al.
(författare)
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Characterization of human embryonic stem cell lines by the International Stem Cell Initiative
- 2007
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Ingår i: Nature Biotechnology. - : Springer Science and Business Media LLC. - 1087-0156 .- 1546-1696. ; 25:7, s. 803-816
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Tidskriftsartikel (refereegranskat)abstract
- The International Stem Cell Initiative characterized 59 human embryonic stem cell lines from 17 laboratories worldwide. Despite diverse genotypes and different techniques used for derivation and maintenance, all lines exhibited similar expression patterns for several markers of human embryonic stem cells. They expressed the glycolipid antigens SSEA3 and SSEA4, the keratan sulfate antigens TRA-1-60, TRA-1-81, GCTM2 and GCT343, and the protein antigens CD9, Thy1 (also known as CD90), tissue- nonspecific alkaline phosphatase and class 1 HLA, as well as the strongly developmentally regulated genes NANOG, POU5F1 (formerly known as OCT4), TDGF1, DNMT3B, GABRB3 and GDF3. Nevertheless, the lines were not identical: differences in expression of several lineage markers were evident, and several imprinted genes showed generally similar allele-specific expression patterns, but some gene-dependent variation was observed. Also, some female lines expressed readily detectable levels of XIST whereas others did not. No significant contamination of the lines with mycoplasma, bacteria or cytopathic viruses was detected.
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| 16. |
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| 17. |
- Bergin, Michael J., et al.
(författare)
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Fuel Injection and Mean Swirl Effects on Combustion and Soot Formation in Heavy Duty Diesel Engines
- 2007
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Ingår i: SAE, Session: Compression Ignition Combustion Processes (Part 2of 2)..
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Konferensbidrag (refereegranskat)abstract
- High-speed video imaging in a swirl-supported (Rs = 1.7), direct-injection heavy-duty diesel engine operated with moderate-to-high EGR rates reveals a distinct correlation between the spatial distribution of luminous soot and mean flow vorticity in the horizontal plane. The temporal behavior of the experimental images, as well as the results of multi-dimensional numerical simulations, show that this soot-vorticity correlation is caused by the presence of a greater amount of soot on the windward side of the jet. The simulations indicate that while flow swirl can influence pre-ignition mixing processes as well as post-combustion soot oxidation processes, interactions between the swirl and the heat release can also influence mixing processes. Without swirl, combustion-generated gas flows influence mixing on both sides of the jet equally. In the presence of swirl, the heat release occurs on the leeward side of the fuel sprays. Asymmetric combustion-induced flows alter the vorticity on the leeward side of the jet and lead to better entrainment and fuel-air mixing during the period of peak heat release. This leads to lower local equivalence ratio and lower soot production rates with swirl.
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| 18. |
- Brammer, Karla S., et al.
(författare)
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Improved bone-forming functionality on diameter-controlled TiO2 nanotube surface
- 2009
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Ingår i: Acta Biomaterialia. - : Elsevier BV. - 1878-7568 .- 1742-7061. ; 5:8, s. 3215-3223
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Tidskriftsartikel (refereegranskat)abstract
- The titanium dioxide (TiO2) nanotube surface enables significantly accelerated osteoblast adhesion and exhibits strong bonding with bone. We prepared various sizes (30-100 nm diameter) of titanium dioxide (TiO2) nanotubes on titanium substrates by anodization and investigated the osteoblast cellular behavior in response to these different nanotube sizes. The unique and striking result of this study is that a change in osteoblast behavior is obtained in a relatively narrow range of nanotube dimensions, with small diameter (similar to 30 nm) nanotubes promoting the highest degree of osteoblast adhesion, while larger diameter (70-100 nm) nanotubes elicit a lower population of cells with extremely elongated cellular morphology and much higher alkaline phosphatase levels. Increased elongation of nuclei was also observed with larger diameter nanotubes. By controlling the nanotopography, large diameter nanotubes, in the similar to 100 min regime, induced extremely elongated cellular shapes, with an aspect ratio of 11:1, which resulted in substantially enhanced up-regulation of alkaline phosphatase activity, suggesting greater bone-forming ability than nanotubes with smaller diameters. Such nanotube structures, already being a strongly osseointegrating implant material, offer encouraging implications for the development and optimization of novel orthopedics-related treatments with precise control toward desired cell and bone growth behavior. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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| 19. |
- Enejder, Annika, 1969, et al.
(författare)
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Raman spectroscopy for noninvasive glucose measurements
- 2005
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Ingår i: Journal of Biomedical Optics. - 1560-2281 .- 1083-3668. ; 10:3, s. 031114 (artno)-
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Tidskriftsartikel (refereegranskat)abstract
- We report the first successful study of the use of Raman spectroscopy for quantitative, noninvasive ("transcutaneous") measurement of blood analytes, using glucose as an example. As an initial evaluation of the ability of Raman spectroscopy to measure glucose transcutaneously, we studied 17 healthy human subjects whose blood glucose levels were elevated over a period of 2-3 h using a standard glucose tolerance test protocol. During the test, 461 Raman spectra were collected transcutaneously along with glucose reference values provided by standard capillary blood analysis. A partial least squares calibration was created from the data from each subject and validated using leave-one-out cross validation. The mean absolute errors for each subject were 7.8% +/- 61.8% (mean +/- std) with R-2 values of 0.83 +/- 0.10. We provide spectral evidence that the glucose spectrum is an important part of the calibrations by analysis of the calibration regression vectors. (c) 2005 Society of Photo-Optical Instrumentation Engineers.
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| 20. |
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| 21. |
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| 22. |
- Oh, Il-Chan, et al.
(författare)
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Comparative seed morphology and character evolution in the genus Lysimachia (Myrsinaceae) and related taxa
- 2008
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Ingår i: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 271:3-4, s. 177-197
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Tidskriftsartikel (refereegranskat)abstract
- We investigated seed morphology in 34 species of the genus Lysimachia and in 14 species and two subspecies of six additional genera (Anagallis, Ardisiandra, Asterolinon, Glaux, Pelletiera, Trientalis), which have been shown to be closely related to, or are placed within Lysimachia in previous molecular studies. We studied seed shape, seed coat structure, and seed coat surface patterns. Three major types of seed shape were identified: (1) sectoroid, (2) polyhedral, and (3) coarsely rugose with concave hilar area. In addition, seeds may be keeled or winged. The outer layer of the seed coat is either sponge-like and adhering only loosely to the inner seed coat or it is thin and tightly adhering to the underlying tissue. Seed surface patterns can be divided into six main types: (1) reticulate, (2) tuberculate, (3) vesiculose, (4) colliculate, (5) undulate, or (6) poroid-alveolate. Seed surface patterns are mostly congruent with molecular phylogenetic relationships. A reticulate surface pattern is diagnostic of, e.g. Lysimachia subgenera Palladia and Hawaiian Lysimachiopsis. Mapping seed characters onto a recent phylogenetic tree, reveals that they provide potentially synapomorphic character states for various subclades of Lysimachia. Salient examples include a rugose seed shape, which turns out to be synapomorphic for the clade comprising the genus Pelletiera plus Asterolinon linum-stellatum and a sponge-like outer seed coat layer, which characterizes a clade with Lysimachia vulgaris, L. thyrsiflora, and L. terrestris, with an analogue that apparently evolved in parallel in Trientalis europaea. We also discuss possible habitat factors that may have favored the independent evolution of particular seed types such as winged seeds in various lineages.
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| 23. |
- Oh, I., et al.
(författare)
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Comparative analysis of plant dynamics by size : Korean manufacturing
- 2009
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Ingår i: Japanese Economic Review. - : Springer Science and Business Media LLC. - 1352-4739 .- 1468-5876. ; 60:4, s. 512-538
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Tidskriftsartikel (refereegranskat)abstract
- A comparative analysis on Korean manufacturing plants is performed by size of plants and sources of TFP growth are decomposed into entry, exit, and survival effects of plants, focusing on the pre- and post-crisis periods. Additional survival analyses investigate internal and external determinants of the survival of plants. The results indicate that the exit of small- and medium-sized establishments (SMEs) with higher productivity is becoming problematic in the post-crisis period. The improvements in large-scale establishments (LSEs) after the crisis appeared to occur generally in high-technology industrial sectors; SMEs in low-technology industries are suffering from a sluggish market selection process. ©2009 The Authors. Journal compilation ©2009 Japanese Economic Association.
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| 24. |
- Oh, I., et al.
(författare)
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Evaluation of credit guarantee policy using propensity score matching
- 2009
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Ingår i: Small Business Economics. - : Springer Science and Business Media LLC. - 0921-898X .- 1573-0913. ; 33:3, s. 335-351
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Tidskriftsartikel (refereegranskat)abstract
- In this article, we evaluate the effect of the credit guarantee policy by comparing a large sample of guaranteed firms and matched non-guaranteed firms from 2000 to 2003. The sample firms are compared with respect to growth rates of different performance indicators including: productivity, sales, employment, investment, R&D, wage level, and the survival of firms in the post crisis period. In order to avoid the selectivity problem, propensity score matching methodologies are adopted. Results suggest that credit guarantees influenced significantly firms’ ability to maintain their size, and increase their survival rate, but not to increase their R&D and investment and hence, their growth in productivity. Moreover, due to the adverse selection problem, firms with lower productivity were receiving guarantees. ©Springer Science+Business Media, LLC. 2008.
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| 25. |
- Oh, I., et al.
(författare)
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Total factor productivity in Korean manufacturing industries
- 2008
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Ingår i: Global Economic Review. - : Informa UK Limited. - 1226-508X .- 1744-3873. ; 37:1, s. 23-50
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Tidskriftsartikel (refereegranskat)abstract
- In this study, parametric and non-parametric methods are employed to measure the total factor productivity (TFP) growth in the Korean manufacturing industry from 1993 to 2003. The analysis period contains both periods before and after the Asian financial crisis. The TFP growth rate is decomposed into different components. Also different elasticities are reported. By classifying the results by period and classifying a number of time invariant firm characteristics, such as sector, size, and location of firms, we observe systematic heterogeneity for each characteristic. We discuss the underlying causal factors. The results from a non-parametric approach are also compared with those of a parametric approach. ©2008 Institute of East and West Studies, Yonsei University, Seoul.
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| 26. |
- Suh, D., et al.
(författare)
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Do software intellectual property rights affect the performance of firms? : Case study of South Korea
- 2008
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Ingår i: Proc. - Int. Conf. Softw. Eng. Adv., ICSEA, Inlucdes ENTISY: Int. Workshop Enterp. Inf. Sys.. - 9780769533728 ; , s. 307-312
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Konferensbidrag (refereegranskat)abstract
- The aim of this study is to find the relationship between software intellectual property rights (IPRs) and the performance of software firms in South Korea. In order to measure the performance of software firms, we employed the concept of efficiency of Data Envelopment Analysis (DEA). With measured efficiency, we use tobit regression to investigate which IPR has a stronger effect on efficiency. The empirical results show an obvious tendency: the average efficiency of software firms having any kind of software IPR is higher than that of firms not having them. Moreover, the results of tobit analysis show that both software copyrights and patents have a positive effect on the performance of software firms, and that the effect of patents is higher than that of copyrights.
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