| 1. |
- Actis, M., et al.
(författare)
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Design concepts for the Cherenkov Telescope Array CTA : an advanced facility for ground-based high-energy gamma-ray astronomy
- 2011
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Ingår i: Experimental astronomy. - : Springer. - 0922-6435 .- 1572-9508. ; 32:3, s. 193-316
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Tidskriftsartikel (refereegranskat)abstract
- Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.
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| 2. |
- Cirasuolo, M., et al.
(författare)
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MOONS: the Multi-Object Optical and Near-infrared Spectrograph for the VLT
- 2014
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Ingår i: Ground-based and Airborne Instrumentation for Astronomy V. - : SPIE. - 1996-756X .- 0277-786X. ; 9147, s. 91470-91470
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Konferensbidrag (refereegranskat)abstract
- MOONS (the Multi-Object Optical and Near-infrared Spectrograph) has been selected by ESO as a third-generation instrument for the Very Large Telescope (VLT). The light grasp of the large collecting area offered by the VLT (8.2m diameter), combined with the large multiplex and wavelength coverage (optical to near-IR: 0.8 -1.8 mu m) of MOONS will provide the European astronomical community with a powerful, unique instrument able to pioneer a wide range of Galactic, extragalactic and cosmological studies, and it will provide crucial follow-up for major facilities such as Gaia, VISTA, Euclid and LSST. MOONS has the observational power needed to unveil galaxy formation and evolution over the entire history of the Universe, from stars in our Milky Way, through the redshift desert, and up to the epoch of very first galaxies and reionization of the Universe at redshifts of z > 8-9, just a few million years after the Big Bang. From five years of observations MOONS will provide high-quality spectra for > 3M stars in our Galaxy and the Local Group, and for 1-2M galaxies at z > 1 (for an SDSS-like survey), promising to revolutionize our understanding of the Universe. The baseline design consists of similar to 1000 fibres, deployable over a field-of-view of similar to 500 arcmin(2), the largest patrol field offered by the Nasmyth focus at the VLT. The total wavelength coverage is 0.8 -1.8 mu m with two spectral resolving powers: in the medium-resolution mode (R similar to 4,000-6,000) the entire wavelength range is observed simultaneously, while the high-resolution mode will cover three selected sub-regions simultaneously: one region with R similar to 8,000 near the Ca II triplet to measure stellar radial velocities, and two regions at R similar to 20,000 (one in each of the J- and H-bands), for precision measurements of chemical abundances.
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| 3. |
- Aghion, S., et al.
(författare)
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A moiré deflectometer for antimatter
- 2014
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Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- The precise measurement of forces is one way to obtain deep insight into the fundamental interactions present in nature. In the context of neutral antimatter, the gravitational interaction is of high interest, potentially revealing new forces that violate the weak equivalence principle. Here we report on a successful extension of a tool from atom optics—the moiré deflectometer—for a measurement of the acceleration of slow antiprotons. The setup consists of two identical transmission gratings and a spatially resolving emulsion detector for antiproton annihilations. Absolute referencing of the observed antimatter pattern with a photon pattern experiencing no deflection allows the direct inference of forces present. The concept is also straightforwardly applicable to antihydrogen measurements as pursued by the AEgIS collaboration. The combination of these very different techniques from high energy and atomic physics opens a very promising route to the direct detection of the gravitational acceleration of neutral antimatter.
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| 4. |
- Ariga, T., et al.
(författare)
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Measuring GBAR with emulsion detector
- 2014
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Ingår i: International Journal of Modern Physics, Conference Series. - : World Scientific. - 2010-1945. ; 30
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Tidskriftsartikel (refereegranskat)
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| 5. |
- Both, P., et al.
(författare)
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Discrimination of epimeric glycans and glycopeptides using IM-MS and its potential for carbohydrate sequencing
- 2014
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Ingår i: Nature Chemistry. - 1755-4330 .- 1755-4349. ; 6:1, s. 65-74
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Tidskriftsartikel (refereegranskat)abstract
- Mass spectrometry is the primary analytical technique used to characterize the complex oligosaccharides that decorate cell surfaces. Monosaccharide building blocks are often simple epimers, which when combined produce diastereomeric glycoconjugates indistinguishable by mass spectrometry. Structure elucidation frequently relies on assumptions that biosynthetic pathways are highly conserved. Here, we show that biosynthetic enzymes can display unexpected promiscuity, with human glycosyltransferase pp-a-GanT2 able to utilize both uridine diphosphate N-acetylglucosamine and uridine diphosphate N-acetylgalactosamine, leading to the synthesis of epimeric glycopeptides in vitro. Ion-mobility mass spectrometry ( IM-MS) was used to separate these structures and, significantly, enabled characterization of the attached glycan based on the drift times of the monosaccharide product ions generated following collision-induced dissociation. Finally, ion-mobility mass spectrometry following fragmentation was used to determine the nature of both the reducing and non-reducing glycans of a series of epimeric disaccharides and the branched pentasaccharide Man3 glycan, demonstrating that this technique may prove useful for the sequencing of complex oligosaccharides.
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| 6. |
- Heiss, M., et al.
(författare)
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Self-assembled quantum dots in a nanowire system for quantum photonics
- 2013
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Ingår i: Nature Materials. - 1476-4660. ; 12:5, s. 439-444
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Tidskriftsartikel (refereegranskat)abstract
- Quantum dots embedded within nanowires represent one of the most promising technologies for applications in quantum photonics. Whereas the top-down fabrication of such structures remains a technological challenge, their bottom-up fabrication through self-assembly is a potentially more powerful strategy. However, present approaches often yield quantum dots with large optical linewidths, making reproducibility of their physical properties difficult. We present a versatile quantum-dot-innanowire system that reproducibly self-assembles in core-shell GaAs/AlGaAs nanowires. The quantum dots form at the apex of a GaAs/AlGaAs interface, are highly stable, and can be positioned with nanometre precision relative to the nanowire centre. Unusually, their emission is blue-shifted relative to the lowest energy continuum states of the GaAs core. Large-scale electronic structure calculations show that the origin of the optical transitions lies in quantum confinement due to Al-rich barriers. By emitting in the red and self-assembling on silicon substrates, these quantum dots could therefore become building blocks for solid-state lighting devices and third-generation solar cells.
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| 7. |
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| 8. |
- Albert, N.M., et al.
(författare)
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Predictors of Exercise in Ambulatory Patients with Heart Failure
- 2012
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Ingår i: Oral presentation at American Heart Association congress. ; 2012:126
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Konferensbidrag (refereegranskat)abstract
- Background: Although clinical guidelines encourage moderate-vigorous exercise in patients with heart failure (HF), adherence is poor. The purpose of this study was to identify determinants of adherence to moderate-vigorous exercise, so that targeted interventions can be developed. Methods. Using a prospective, correlational design, ambulatory patients with chronic HF from 6 ambulatory clinics in the Midwest and Northeast US and Sweden completed surveys on functional status, current and previous exercise, fatigue, depression, and barriers, knowledge, attitudes, values, and confidence about exercise. Logistic regression models were used to estimate the odds of being a moderate-vigorous exerciser, adjusting for patient characteristics. Results. The cohort of 492 patients had mean (SD) age 63 (±13.6) years; ejection fraction 34.9% (± 14.8%); and BMI 29.3 (± 6.73) kg/ml/m2. Other characteristics were 40.3% ischemic HF etiology; 64.8% male; 76.2% Caucasian; 58.9% married; 30.9% NYHA class III/IV and a low fatigue level of 2.1 (± 0.8) on a 1-5 scale. Only 46% exercised moderately-vigorously and mean (SD) exercise knowledge was poor, 35% (± 0.2%) on a 0-100% scale. After adjusting for patient characteristics such as BMI, gender, smoking status, and insurance type, 18 factors were significantly associated with moderate-vigorous exercise. Those that increased the OR for moderate-vigorous exercise were perceptions of very good health, OR 8.57 (95% CI: 4.09, 19.18); higher self-confidence for exercise, OR 5.74 (3.8, 8.95); lower barriers, OR 3.41 (2.36, 5.06); better attitudes, OR 3.01 (2.2, 4.2); higher perceived value, OR 2.58 (1.83, 3.71); more benefits/motivators, OR 2.25 (1.64, 3.15); all P<0.001 and higher knowledge, OR 1.26 (1.01, 1.57), P=0.04. Conclusion. Among ambulatory patients with chronic HF, knowledge of exercise expectations is low and less than one-half exercise regularly. Adherence to moderate-vigorous exercise is modifiable. Patients need to understand what moderate-vigorous exercise means and its benefits and value related to HF. Interventions that improve confidence and decrease barriers may enhance exercise adherence.
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| 9. |
- Campolo, Orlando, et al.
(författare)
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Acquisition and transmission of selected CTV isolates by Aphis gossypii
- 2014
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Ingår i: JOURNAL OF ASIA-PACIFIC ENTOMOLOGY. - : KOREAN SOC APPLIED ENTOMOLOGY. - 1226-8615. ; 17:3, s. 493-498
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Tidskriftsartikel (refereegranskat)abstract
- Citrus tristeza virus (CTV) is a severe threat to the citrus industry. Disease symptoms and severity may vary depending on the CTV isolates. These are responsible for the decline of trees grafted on sour orange rootstock, or stem pitting on some citrus commercial cultivars regardless of rootstock. In the Calabria region (Italy), CTV was first reported on cultivars imported from other countries. However, recent observations suggested that natural spread of CTV was occurring and a study was needed to determine the epidemiological status and aphid transmission of CTV in Calabria. The role played by local A. gossypii in the spread of CIV was analyzed in the laboratory using various viral acquisition, inoculation periods with three different CTV isolates. Single aphid vectors acquired CTV after a minimum of 30 min acquisition access period (AAP) and were able to transmit the virus after a 60 min inoculation access period (IAP) to healthy plants. A minimum of four aphid vectors were needed to reach 50% transmission probability. The results suggested that the three tested strains are transmitted by A. gossypii in a semi-persistent mode. The results demonstrated that local A. gossypii population can acquire and transmit efficiently the tested virus isolates with serious implications on the virus spread. (C) 2014 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society. Published by Elsevier B.V. All rights reserved.
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| 10. |
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