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3. |
- Andrés, E., et al.
(författare)
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Observation of high-energy neutrinos using Čerenkov detectors embedded deep in Antarctic ice
- 2001
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 410:6827, s. 441-443
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Tidskriftsartikel (refereegranskat)abstract
- Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova2, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water3,4 or ice5. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations1.
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4. |
- Andrés, E., et al.
(författare)
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Recent results from AMANDA
- 2001
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Ingår i: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 16:1C, s. 1013-1015
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Tidskriftsartikel (refereegranskat)abstract
- We present results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope.
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5. |
- Andres, E., et al.
(författare)
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Results from the AMANDA high energy neutrino detector
- 2000
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Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 91:1-3, s. 423-430
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Tidskriftsartikel (refereegranskat)abstract
- This paper briefly summarizes the search for astronomical sources of high-energy neutrinos using the AMANDA-B10 detector. The complete data set from 1997 was analyzed. For Eμ > 10 TeV, the detector exceeds 10,000 m2 in effective area between declinations of 25 and 90 degrees. Neutrinos generated in the atmosphere by cosmic ray interactions were used to verify the overall sensitivity of the detector. The absolute pointing accuracy and angular resolution has been confirmed by the analysis of coincident events between the SPASE air shower array and the AMANDA detector. Preliminary flux limits from point source candidates are presented. For declinations larger than +45 degrees, our results compare favorably to existing limits for sources in the Southern sky. We also present the current status of the searches for high energy neutrino emission from diffusely distributed sources, GRBs, and WIMPs from the center of the earth.
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6. |
- Andres, E., et al.
(författare)
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Selected recent results from AMANDA
- 2001
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Ingår i: ICHEP 2000. Proceedings of the 30th International Conference on High Energy Physics. - : World Scientific. ; , s. 965-968
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Konferensbidrag (refereegranskat)abstract
- We present a selection of results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope. Studies of nearly vertical upgoing muons limit the available parameter space for WIMP dark matter under the assumption that WIMPS are trapped in the earth's gravitational potential well and annihilate with one another near the earth's center.
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7. |
- Askebjer, P., et al.
(författare)
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Optical properties of deep ice at the South Pole : Absorption
- 1997
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Ingår i: Applied Optics. - : Optical Society of America. - 0003-6935 .- 1539-4522. ; 36:18, s. 4168-4180
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Tidskriftsartikel (refereegranskat)abstract
- We discuss recent measurements of the wavelength-dependent absorption coefficients in deep South Pole ice. The method uses transit-time distributions of pulses from a variable-frequency laser sent between emitters and receivers embedded in the ice. At depths of 800-1000 m scattering is dominated by residual air bubbles, whereas absorption occurs both in ice itself and in insoluble impurities. The absorption coefficient increases approximately exponentially with wavelength in the measured interval 410-610 nm. At the shortest wavelength our value is approximately a factor 20 below previous values obtained for laboratory ice and lake ice; with increasing wavelength the discrepancy with previous measurements decreases. At ∼415 to ∼500 nm the experimental uncertainties are small enough for us to resolve an extrinsic contribution to absorption in ice: submicrometer dust particles contribute by an amount that increases with depth and corresponds well with the expected increase seen near the Last Glacial Maximum in Vostok and Dome C ice cores. The laser pulse method allows remote mapping of gross structure in dust concentration as a function of depth in glacial ice.
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9. |
- Karle, A., et al.
(författare)
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Observation of high energy atmospheric neutrinos with AMANDA
- 2000
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Ingår i: AIP Conference Proceedings. - : American Institute of Physics (AIP). ; , s. 823-827
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Konferensbidrag (refereegranskat)abstract
- In 1997 the Antarctic Muon and Neutrino Detector Array (AMANDA) started operating with 10 strings. In an analysis of data taken during the first year of operation 188 atmospheric neutrino candidates were found. Their zenith angle distribution agrees with expectations based on Monte Carlo simulations. A preliminary upper limit is given on a diffuse flux of high energy neutrinos of astrophysical origin.
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10. |
- Askebjer, P., et al.
(författare)
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AMANDA : status report from the 1993-94 campaign and optical properties of the South Pole ice
- 1995
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Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 38:1-3, s. 287-292
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Tidskriftsartikel (refereegranskat)abstract
- We report the first results of the AMANDA detector. During the antarctic summer 1993-94 four strings were deployed between 0.8 an 1 km depth, each equipped with 20 photomultiplier tubes (PMTs). A laser source was used to investigate the optical properties of the ice in situ. We find that the ice is intrinsically extremely transparent. The measured absorption length is 59 ± 3 m, i.e. comparable with the quality of the ultra-pure water used in the IMB and Kamiokande proton-decay and neutrino experiments [1,2] and more than two times longer than the best value reported for laboratory ice [3]. Due to a residual density of air bubbles at these depths, the motion of photons in the medium is randomized. For spherical, smooth bubbles we find that, at 1 km depth, the average distance between collisions is about 25 cm. The measured inverse scattering length on bubbles decreases linearly with increasing depth in the volume of ice investigated. © 1995 Elsevier Science B.V. All rights reserved.
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11. |
- Askebjer, P., et al.
(författare)
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On the age vs depth and optical clarity of deep ice at South Pole
- 1995
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Ingår i: Journal of Glaciology. - 0022-1430 .- 1727-5652. ; 41:139, s. 445-454
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Tidskriftsartikel (refereegranskat)abstract
- The first four strings of phototubes for the AMANDA high-energy neutrino observatory are now frozen in place at a depth of 800 to 1000 m in ice at the South Pole. During the 1995-96 season an additional six strings will be deployed at greater depths. Provided absorption, scattering, and refraction of visible light are sufficiently small, the trajectory of a muon into which a neutrino converts can be determined by using the array of phototubes to measure the arrival times of \v{C}erenkov light emitted by the muon. To help in deciding on the depth for implantation of the six new strings, we discuss models of age vs depth for South Pole ice, we estimate mean free paths for scattering from bubbles and dust as a function of depth, and we assess distortion of light paths due to refraction at crystal boundaries and interfaces between air-hydrate inclusions and normal ice. We conclude that the depth interval 1600 to 1800 m will be suitably transparent for the next six AMANDA strings and, moreover, that the interval 1600 to 2100 m will be suitably transparent for a future 1-km 3 observatory except possibly in a region a few tens of meters thick at a depth corresponding to a peak in the dust concentration at 60 kyr BP.
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12. |
- Askebjer, P., et al.
(författare)
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Optical properties of the South Pole ice at depths between 0.8 and 1 kilometer
- 1995
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Ingår i: Science. - 0036-8075 .- 1095-9203. ; 267:5201, s. 1147-1150
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Tidskriftsartikel (refereegranskat)abstract
- The optical properties of the ice at the geographical South Pole have been investigated at depths between 0.8 and 1 kilometer. The absorption and scattering lengths of visible light (∼515 nanometers) have been measured in situ with the use of the laser calibration setup of the Antarctic Muon and Neutrino Detector Array (AMANDA) neutrino detector. The ice is intrinsically extremely transparent. The measured absorption length is 59 ± 3 meters, comparable with the quality of the ultrapure water used in the Irvine-Michigan-Brookhaven and Kamiokande proton-decay and neutrino experiments and more than twice as long as the best value reported for laboratory ice. Because of a residual density of air bubbles at these depths, the trajectories of photons in the medium are randomized. If the bubbles are assumed to be smooth and spherical, the average distance between collisions at a depth of 1 kilometer is about 25 centimeters. The measured inverse scattering length on bubbles decreases linearly with increasing depth in the volume of ice investigated.
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13. |
- Askebjer, P., et al.
(författare)
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UV and optical light transmission properties in deep ice at the South Pole
- 1997
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Ingår i: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 24:11, s. 1355-1358
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Tidskriftsartikel (refereegranskat)abstract
- Both absorption and scattering of light at wavelengths 410 to 610 nanometers were measured in the South Pole ice at depths 0.8 to 1 kilometer with the laser calibration system of the Antarctic Muon And Neutrino Detector Array (AMANDA). At the shortest wavelengths the absorption lengths exceeded 200 meters - an order of magnitude longer than has been reported for laboratory ice. The absorption shows a strong wavelength dependence while the scattering length is found to be independent of the wavelength, consistent with the hypothesis of a residual density of air bubbles in the ice. The observed linear decrease of the inverse scattering length with depth is compatible with an earlier measurement by the AMANDA collaboration (at ∼515 nanometers).
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14. |
- Baboota, Ritesh, et al.
(författare)
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Chronic hyperinsulinemia promotes human hepatocyte senescence
- 2022
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Ingår i: Molecular Metabolism. - : Elsevier BV. - 2212-8778. ; 64
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Cellular senescence, an irreversible proliferative cell arrest, is caused by excessive intracellular or extracellular stress/damage. Increased senescent cells have been identified in multiple tissues in different metabolic and other aging-related diseases. Recently, several human and mouse studies emphasized the involvement of senescence in development and progression of NAFLD. Hyperinsulinemia, seen in obesity, metabolic syndrome, and other conditions of insulin resistance, has been linked to senescence in adipocytes and neurons. Here, we investigate the possible direct role of chronic hyperinsulinemia in the development of senescence in human hepatocytes. Methods: Using fluorescence microscopy, immunoblotting, and gene expression, we tested senescence markers in human hepatocytes subjected to chronic hyperinsulinemia in vitro and validated the data in vivo by using liver-specific insulin receptor knockout (LIRKO) mice. The consequences of hyperinsulinemia were also studied in senescent hepatocytes following doxorubicin as a model of stress-induced senescence. Furthermore, the effects of senolytic agents in insulin- and doxorubicin-treated cells were analyzed. Results: Results showed that exposing the hepatocytes to prolonged hyperinsulinemia promotes the onset of senescence by increasing the expression of p53 and p21. It also further enhanced the senescent phenotype in already senescent hepatocytes. Addition of insulin signaling pathway inhibitors prevented the increase in cell senescence, supporting the direct contribution of insulin. Furthermore, LIRKO mice, in which insulin signaling in the liver is abolished due to deletion of the insulin receptor gene, showed no differences in senescence compared to their wild-type counterparts despite having marked hyperinsulinemia indicating these are receptor-mediated effects. In contrast, the persistent hyperinsulinemia in LIRKO mice enhanced senescence in white adipose tissue. In vitro, senolytic agents dasatinib and quercetin reduced the prosenescent effects of hyperinsulinemia in hepatocytes. Conclusion: Our findings demonstrate a direct link between chronic hyperinsulinemia and hepatocyte senescence. This effect can be blocked by reducing the levels of insulin receptors or administration of senolytic drugs, such as dasatinib and quercetin.
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15. |
- Bergstrom, L., et al.
(författare)
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The AMANDA experiment : Status and prospects for indirect dark matter detection
- 1996
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Ingår i: The identification of dark matter. Proceedings, 1st International Workshop, Sheffield, UK, September 8-12, 1996. ; , s. 521-528
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Konferensbidrag (refereegranskat)abstract
- At the AMANDA South Pole site, four new holes were drilled to depths 2050m to 2180 m and instrumented with 86 photomultipliers (PMTs) at depths1520-2000 m. Of these PMTs 79 are working, with 4-ns timing resolutionand noise rates 300 to 600 Hz. Various diagnostic devices were deployedand are working. An observed factor 60 increase in scattering length anda sharpening of the distribution of arrival times of laser pulses relative tomeasurements at 800-1000 m showed that bubbles are absent below 1500 m.Absorption lengths are 100 to 150 m at wavelengths in the blue and UV to337 nm. Muon coincidences are seen between the SPASE air shower arrayand the AMANDA PMTs at 800-1000 m and 1500-1900 m. The muon trackrate is 30 Hz for 8-fold triggers and 10 Hz for 10-fold triggers. The presentarray is the nucleus for a future expanded array. The potential of AMANDAfor SUSY dark matter search through the detection of high-energy neutrinosfrom the centre of the Sun or Earth is discussed.
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16. |
- Bloom, A. C., et al.
(författare)
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Deletion of the membrane complement inhibitor CD59a drives age and gender-dependent alterations to bone phenotype in mice
- 2016
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Ingår i: Bone. - : Elsevier BV. - 8756-3282. ; 84, s. 253-261
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Tidskriftsartikel (refereegranskat)abstract
- Degenerative joint diseases such as osteoarthritis are characterised by aberrant region-specific bone formation and abnormal bone mineral content. A recent study suggested a role for the complement membrane attack complex in experimental models of osteoarthritis. Since CD59a is the principal regulator of the membrane attack complex in mice, we evaluated the impact of CD59a gene deletion upon maintenance of bone architecture. In vivo bone morphology analysis revealed that male CD59a-deficient mice have increased femur length and cortical bone volume, albeit with reduced bone mineral density. However, this phenomenon was not observed in female mice. Histomorphometric analysis of the trabecular bone showed increased rates of bone homeostasis, with both increased bone resorption and mineral apposition rate in CD59a-deficient male mice. When bone cells were studied in isolation, in vitro osteoclastogenesis was significantly increased in male CD59a-deficient mice, although osteoblast formation was not altered. Our data reveal, for the first time, that CD59a is a regulator of bone growth and homeostasis. CD59a ablation in male mice results in longer and wider bones, but with less density, which is likely a major contributing factor for their susceptibility to osteoarthritis. These findings increase our understanding of the role of complement regulation in degenerative arthritis.
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17. |
- Coath, W., et al.
(författare)
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Operationalizing the centiloid scale for F-18 florbetapir PET studies on PET/MRI
- 2023
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Ingår i: Alzheimer's and Dementia: Diagnosis, Assessment and Disease Monitoring. - 2352-8729. ; 15:2
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTIONThe Centiloid scale aims to harmonize amyloid beta (A beta) positron emission tomography (PET) measures across different analysis methods. As Centiloids were created using PET/computerized tomography (CT) data and are influenced by scanner differences, we investigated the Centiloid transformation with data from Insight 46 acquired with PET/magnetic resonanceimaging (MRI). METHODSWe transformed standardized uptake value ratios (SUVRs) from 432 florbetapir PET/MRI scans processed using whole cerebellum (WC) and white matter (WM) references, with and without partial volume correction. Gaussian-mixture-modelling-derived cutpoints for A beta PET positivity were converted. RESULTSThe Centiloid cutpoint was 14.2 for WC SUVRs. The relationship between WM and WC uptake differed between the calibration and testing datasets, producing implausibly low WM-based Centiloids. Linear adjustment produced a WM-based cutpoint of 18.1. DISCUSSIONTransformation of PET/MRI florbetapir data to Centiloids is valid. However, further understanding of the effects of acquisition or biological factors on the transformation using a WM reference is needed. HIGHLIGHTSCentiloid conversion of amyloid beta positron emission tomography (PET) data aims to standardize results.Centiloid values can be influenced by differences in acquisition.We converted florbetapir PET/magnetic resonance imaging data from a large birth cohort.Whole cerebellum referenced values could be reliably transformed to Centiloids. White matter referenced values may be less generalizable between datasets.
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21. |
- Hulth, P. O., et al.
(författare)
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The AMANDA experiment
- 1996
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Ingår i: Neutrino '96. Proceedings, 17th International Conference on Neutrino Physics and Astrophysics, Helsinki, Finland, June 13-19, 1996. ; , s. 518-523
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Konferensbidrag (refereegranskat)abstract
- At the AMANDA South Pole site, four new holes were drilled to depths 2050 m to 2180 m and instrumented with 86 photomultipliers (PMTs) at depths 1520-2000 m. Of these PMTs 79 are working, with 4-ns timing resolution and noise rates 300 to 600 Hz. Various diagnostic devices were deployed and are working. An observed factor 60 increase in scattering length and a sharpening of the distribution of arrival times of laser pulses relative to measurements at 800-1000 m showed that bubbles are absent below 1500 m. Absorption lengths are 100 to 150 m at wavelengths in the blue and UV to 337 nm. Muon coincidences are seen between the SPASE air shower array and the AMANDA PMTs at 800-1000 m and 1500-1900 m. The muon track rate is 30 Hz for 8-fold triggers and 10 Hz for 10-fold triggers. The present array is the nucleus for a future expanded array.
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24. |
- Kehoe, Laura, et al.
(författare)
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Make EU trade with Brazil sustainable
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6438, s. 341-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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25. |
- Miller, T. C., et al.
(författare)
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Particle astrophysics in antarctica
- 1996
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Ingår i: International School of Cosmic Ray Astrophysics: 10th Course: Toward the Millennium in Astrophysics: Problems and Prospects 16-26 Jun 1996. Erice, Italy. ; , s. 157-166
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Konferensbidrag (refereegranskat)
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32. |
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33. |
- Arheimer, Berit, et al.
(författare)
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The IAHS Science for Solutions decade, with Hydrology Engaging Local People IN a Global world (HELPING)
- 2024
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Ingår i: Hydrological Sciences Journal. - 0262-6667 .- 2150-3435.
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Tidskriftsartikel (refereegranskat)abstract
- The new scientific decade (2023-2032) of the International Association of Hydrological Sciences (IAHS) aims at searching for sustainable solutions to undesired water conditions - may it be too little, too much or too polluted. Many of the current issues originate from global change, while solutions to problems must embrace local understanding and context. The decade will explore the current water crises by searching for actionable knowledge within three themes: global and local interactions, sustainable solutions and innovative cross-cutting methods. We capitalise on previous IAHS Scientific Decades shaping a trilogy; from Hydrological Predictions (PUB) to Change and Interdisciplinarity (Panta Rhei) to Solutions (HELPING). The vision is to solve fundamental water-related environmental and societal problems by engaging with other disciplines and local stakeholders. The decade endorses mutual learning and co-creation to progress towards UN sustainable development goals. Hence, HELPING is a vehicle for putting science in action, driven by scientists working on local hydrology in coordination with local, regional, and global processes.
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34. |
- ASKEBJER, P, et al.
(författare)
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AMANDA - STATUS-REPORT FROM THE 1993-94 CAMPAIGN AND OPTICAL-PROPERTIES OF THE SOUTH-POLE ICE
- 1995
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Ingår i: NUCLEAR PHYSICS B. - : ELSEVIER SCIENCE BV. - 0550-3213. ; , s. 287-292
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We report the first results of the AMANDA detector. During the antarctic summer 1993-94 four strings were deployed between 0.8 an 1 km depth, each equipped with 20 photomultiplier tubes (PMTs). A laser source was used to investigate the optical properties
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35. |
- ASKEBJER, P, et al.
(författare)
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ON THE AGE VS DEPTH AND OPTICAL CLARITY OF DEEP ICE AT THE SOUTH-POLE
- 1995
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Ingår i: JOURNAL OF GLACIOLOGY. - : INT GLACIOL SOC. - 0022-1430. ; 41:139, s. 445-454
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The first four strings of phototubes for the AMANDA high-energy neutrino observatory are now frozen in place at a depth of 800-1000 m in ice at the South Pole. During the 1995-96 season, as many as six more strings will be deployed at greater depths. Prov
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36. |
- Askebjer, P, et al.
(författare)
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Optical properties of deep ice at the South Pole: Absorption
- 1997
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Ingår i: APPLIED OPTICS. - : OPTICAL SOC AMER. - 0003-6935. ; 36:18, s. 4168-4180
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We discuss recent measurements of the wavelength-dependent absorption coefficients in deep South Pole ice. The method uses transit-time distributions of pulses from a variable-frequency laser sent between emitters and receivers embedded in the ice. At dep
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37. |
- ASKEBJER, P, et al.
(författare)
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OPTICAL-PROPERTIES OF THE SOUTH-POLE ICE AT DEPTHS BETWEEN 0.8 AND 1 KILOMETER
- 1995
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Ingår i: SCIENCE. - : AMER ASSOC ADVAN SCIENCE. - 0036-8075. ; 267:5201, s. 1147-1150
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The optical properties of the ice at the geographical South Pole have been investigated at depths between 0.8 and 1 kilometer. The absorption and scattering lengths of visible light (similar to 515 nanometers) have been measured in situ with the use of th
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38. |
- Askebjer, P, et al.
(författare)
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UV and optical light transmission properties in deep ice at the South Pole
- 1997
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Ingår i: GEOPHYSICAL RESEARCH LETTERS. - : AMER GEOPHYSICAL UNION. - 0094-8276. ; 24:11, s. 1355-1358
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Both absorption and scattering of light at wavelengths 410 to 610 nanometers were measured in tile South Pole ice at depths 0.8 to 1 kilometer with the laser calibration system of the Antarctic Muon And Neutrino Detector Array (AMANDA). At the shortest wa
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39. |
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40. |
- Blomgren, J., et al.
(författare)
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Putting co-creation into practice : lessons learned from developing a midwife-led quality improvement intervention
- 2023
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Ingår i: Global Health Action. - : Taylor and Francis Ltd.. - 1654-9716 .- 1654-9880. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Integrating evidence-based midwifery practices improves healthcare quality for women and newborns, but an evidence-to-practice gap exists. Co-created quality improvement initiatives led by midwives could bridge this gap, prevent resource waste and ensure intervention relevance. However, how to co-create a midwife-led quality improvement intervention has not been scientifically explored. Objective: The objective of this study is to describe the co-creation process and explore the needs and determinants of a midwife-led quality improvement targeting evidence-based midwifery practices. Methods: A qualitative deductive approach using the Consolidated Framework for Advancing Implementation Science was employed. An analysis matrix based on the framework was developed, and the data were coded according to categories. Data were gathered from interviews, focus group discussions, observations and workshops. New mothers and birth companions (n = 19) were included through convenience sampling. Midwives (n = 26), professional association representatives, educators, policymakers, managers, and doctors (n = 7) were purposely sampled. Results: The co-creation process of the midwife-led Quality Improvement intervention took place in four stages. Firstly, core elements of the intervention were established, featuring a group of midwife champions leading a quality improvement initiative using a train-the-trainers approach. Secondly, the intervention needs, context and determinants were explored, which showed knowledge and skills gaps, a lack of shared goals among staff, and limited resources. However, there was clear relevance, compatibility, and mission alignment for a midwife-led quality improvement at all levels. Thirdly, during co-creation workshops with new mothers and companions, the consensus was to prioritise improved intrapartum support, while workshops with midwives identified enhancing the use of birth positions and perineal protection as key focus areas for the forthcoming Quality Improvement intervention. Lastly, the findings guided intervention strategies, including peer-assisted learning, using existing structures, developing educational material, and building stakeholder relationships. Conclusions: This study provides a practical example of a co-creation process for a midwife-led quality improvement intervention, which can be relevant in different maternity care settings. © 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
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41. |
- Dai, L, et al.
(författare)
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Functional vitamin K insufficiency, vascular calcification and mortality in advanced chronic kidney disease: A cohort study
- 2021
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 16:2, s. e0247623-
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Tidskriftsartikel (refereegranskat)abstract
- Patients with chronic kidney disease (CKD) suffer from vitamin K deficiency and are at high risk of vascular calcification (VC) and premature death. We investigated the association of functional vitamin K deficiency with all-cause mortality and whether this association is modified by the presence of VC in CKD stage 5 (CKD G5). Plasma dephosphorylated-uncarboxylated matrix Gla-protein (dp-ucMGP), a circulating marker of functional vitamin K deficiency, and other laboratory and clinical data were determined in 493 CKD G5 patients. VC was assessed in subgroups by Agatston scoring of coronary artery calcium (CAC) and aortic valve calcium (AVC). Backward stepwise regression did not identify dp-ucMGP as an independent determinant of VC. During a median follow-up of 42 months, 93 patients died. Each one standard deviation increment in dp-ucMGP was associated with increased risk of all-cause mortality (sub-hazard ratio (sHR) 1.17; 95% confidence interval, 1.01–1.37) adjusted for age, sex, cardiovascular disease, diabetes, body mass index, inflammation, and dialysis treatment. The association remained significant when further adjusted for CAC and AVC in sub-analyses (sHR 1.22, 1.01–1.48 and 1.27, 1.01–1.60, respectively). In conclusion, functional vitamin K deficiency associates with increased mortality risk that is independent of the presence of VC in patients with CKD G5.
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42. |
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43. |
- Erlandsson, Helen, et al.
(författare)
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Scoring of medial arterial calcification predicts cardiovascular events and mortality after kidney transplantation
- 2022
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 291:6, s. 813-823
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Tidskriftsartikel (refereegranskat)abstract
- Background Progression of vascular calcification causes cardiovascular disease, which is the most common cause of death in chronic kidney failure and after kidney transplantation (KT). The prognostic impact of the extent of medial vascular calcification at KT is unknown. Methods In this prospective cohort study, we investigated the impact of medial calcification compared to a mix of intimal and medial calcification represented by coronary artery calcification (CAC score) and aortic valve calcification in 342 patients starting on kidney failure replacement therapy. The primary outcomes were cardiovascular events (CVE) and death. The median follow-up time was 6.4 years (interquartile range 3.7-9.6 years). Exposure was CAC score and arteria epigastrica medial calcification scored as none, mild, moderate, or severe by a pathologist at time of KT (n = 200). We divided the patients according to kidney failure replacement therapy during follow-up, that is, living donor KT, deceased donor KT, or dialysis. Results Moderate to severe medial calcification in the arteria epigastrica was associated with higher mortality (p = 0.001), and the hazard ratio for CVE was 3.1 (95% confidence interval [CI] 1.12-9.02, p < 0.05) compared to no or mild medial calcification. The hazard ratio for 10-year mortality in the dialysis group was 33.6 (95% CI, 10.0-113.0, p < 0.001) compared to living donor recipients, independent of Framingham risk score and prevalent CAC. Conclusion Scoring of medial calcification in the arteria epigastrica identified living donor recipients as having 3.1 times higher risk of CVE, independent of traditional risk factors. The medial calcification score could be a reliable method to identify patients with high and low risk of CVE and mortality following KT.
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44. |
- Erlandsson, Kerstin, 1961-, et al.
(författare)
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Half-time evaluation of a new 4-year Ph.D. program in nursing and midwifery at the University of Gondar, Ethiopia
- 2021
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Ingår i: Global Health Action. - : Taylor and Francis Ltd.. - 1654-9716 .- 1654-9880. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- A new four-year Ph.D. programme in nursing and midwifery, the first of its kind in Ethiopia, was started in 2018/2019 at the University of Gondar when eight doctoral students in nursing and midwifery entered the program. We who have been involved see this as an appropriate time to evaluate what has been accomplished to date and to look toward future possibilities. Our aim in carrying out such an evaluation and presenting our findings is in part to determine if similar programs might be developed in other similar settings and in part to learn what modifications to the present program might be considered. The key elements of a questionnaire survey with closed and open response alternatives were based on the content, structure and learning outcomes of the home university Ph.D. programme as described in the curriculum. The questionnaire responses captured changes that would be needed to maintain a fully satisfactory programme that blends onsite instruction and online access to faculty resulting in a twenty-first century blended Ph.D. programme. Improved dialogue between the home university faculty and the external supervisors is needed. The programme can provide a career pathway that midwifery and nursing educators can follow in their own country rather than having to leave to study in another country. The findings provide insight into the feasibility of extending similar Ph.D. programmes to other parts of East Africa and with the SDG 5 in mind with an increased focus on women leadership. The justification for this initiative is to meet the need for more nursing and midwifery faculty who can provide quality midwifery and nursing education in East African countries. Retention of these professionals will help to deal with the shortage of healthcare personnel and will provide better care for the general population. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
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45. |
- Erlandsson, Kerstin, 1961-, et al.
(författare)
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Implementing an internet-based capacity building program for interdisciplinary midwifery-lead teams in Ethiopia, Kenya Malawi and Somalia
- 2021
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Ingår i: Sexual & Reproductive HealthCare. - : Elsevier B.V.. - 1877-5756 .- 1877-5764. ; 30
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Tidskriftsartikel (refereegranskat)abstract
- The Swedish care model MIDWIZE defined as midwife-led interdisciplinary care and zero separation between mother and newborn, was implemented in 2020–21 in Ethiopia, Kenya, Malawi, and Somalia in a capacity building programme funded by the Swedish Institute. Objective: To determine the feasibility of using an internet-based capacity building programme contributing to effective midwifery practices in the labour rooms through implementation of dynamic birthing positions, delayed umbilical cord clamping and skin-to-skin care of newborns in the immediate postnatal period. Methods: The design is inspired by process evaluation. Focus group discussions with policy leaders, academicians, and clinicians who participated in the capacity building programme were carried out. Before and after the intervention, the numbers for dynamic birthing positions, delayed umbilical cord clamping and skin-to-skin care of the newborn in the immediate postnatal period were detected. Results: Participants believed the internet-based programme was appropriate for their countries’ contexts based on their need for improved leadership and collaboration, the need for strengthened human resources, and the vast need for improved outcomes of maternal and newborn health. Conclusion: The findings provide insight into the feasibility to expand similar online capacity building programmes in collaboration with onsite policy leaders, academicians, and clinicians in sub-Saharan African countries with an agenda for improvements in maternal and child health. © 2021
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46. |
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47. |
- Ferede, A. J., et al.
(författare)
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Patients’ perceptions of caring behaviors at referral hospitals in Ethiopia : A cross-sectional survey
- 2023
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Ingår i: International Journal of Nursing Sciences. - : Chinese Nursing Association. - 2352-0132. ; 10:3, s. 391-397
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The purpose of this study was to determine patients’ perceptions of nurse caring behaviors and to identify factors associated with these perceptions. Methods: A cross-sectional study was conducted at three referral hospitals in Ethiopia. A consecutive sample of male and female patients (n = 652, response rate 98.8%) was interviewed using the Amharic version of the Caring Behaviors Inventory-16 (CBI-16, including four subscales: Assurance, Knowledge and skill, Respectful, and Connectedness) and the Patient Satisfaction Instrument (PSI). Socio-demographic and clinical factors associated with perceptions of caring behaviors were identified using multiple linear regression analysis. Results: Patients’ perceptions of nurse caring behaviors were high (total Mean = 4.86, SD = 0.72). Behaviors related to the Assurance subscale were rated the highest. The multiple linear regression analysis result showed several socio-demographic and clinical factors statistically significantly associated with patients’ perceptions of caring behaviors (total mean scores). Patients who were 40–49 years (B = −0.19, P = 0.012) and single (B = −0.13, P = 0.03) scored lower on total CBI-16 scores. Whereas, patients who had a higher educational level (B = 0.35, P = 0.001), cared for at surgery units (B = 0.11, P = 0.027), and reported having spent more time with a nurse in the past 8-h shift (B = 0.16, P < 0.001) were more likely to have higher perceptions of the care they received. The CBI-16 was positively correlated with satisfaction with received care, as measured with the Patient Satisfaction Instrument (r = 0.62, P < 0.001). Conclusion: Hospitalized patients in Ethiopia have overall high perceptions of nurse caring behaviors, especially with regard to physical-based caring, while their expectations of emotional-focused care are lower. We identified patients who were in need of care, patients aged 40–49 years and single. The time spent with nurses plays a pivotal role in patients’ perceptions of nurse caring behaviors. © 2023 The Authors
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48. |
- Gallet, G., et al.
(författare)
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Thermal oxidation of poly(ethylene oxide-propylene oxide-ethylene oxide) triblock copolymer : focus on low molecular weight degradation products
- 2002
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Ingår i: Polymer degradation and stability. - 0141-3910 .- 1873-2321. ; 77:1, s. 55-66
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Tidskriftsartikel (refereegranskat)abstract
- The oxidative thermal degradation of poloxamer 407, a poly(ethylene oxide-propylene oxide-ethylene oxide) triblock copolymer, at 50 and 80 degreesC in air was studied by solid phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS). At 80 degreesC, we found that degradation was initiated on the PPO block of the copolymer by three mechanisms involving hydroperoxyl formation and depropagation. 1,2-propanediol,1-acetate; 1,2-propanediol,2-formate; 1, 2-propanediol,1-acetate, 2-formate and 2-propanone,1-hydroxy were the first degradation products produced. Random chain scissions and a sharp decrease in the molecular weight of the material followed the initiation period. Formic acid and acetic acid, formed upon degradation, participated in esterification reactions leading to the formation of the formate and acetate forms of 1,2-propanediol and ethanediol. Though degradation at 50 degreesC was much slower, the oxidative mechanisms leading to low molecular weight formates and acetates were the same as those observed at 80 degreesC.
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49. |
- Harmenberg, JG, et al.
(författare)
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ME-609: a treatment for recurrent herpes simplex virus infections
- 2003
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Ingår i: Antiviral chemistry & chemotherapy. - : SAGE Publications. - 0956-3202 .- 2040-2066. ; 14:4, s. 205-15
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Tidskriftsartikel (refereegranskat)abstract
- Studies in conventional murine models of HSV infection use immunologically naive animals. These models thus mimic primary infections rather than recurrent infections in humans. We have, therefore, used a newly developed mouse model that more closely mimics recurrent HSV infection in humans. In this model, the mice are infected, and zosteriform HSV-1 infection develops in the presence of a primed immune response using adoptive transfer of immunity (ATI) as we have described previously. Using the ATI mouse model, it has been shown that a more beneficial therapy for recurrent mucocutaneous HSV infection could be achieved by controlling both the viral replication and the inflammatory response to the virus. Topical treatment was initiated in this model at the time of first occurrence of symptoms and was given three times daily for 4 days. Topical treatment with ME-609 (which contains 5% acyclovir and 1% hydrocortisone) in the ATI mouse model was substantially more efficacious than 5% Zovirax® cream, 1% hydrocortisone or no treatment, respectively. The beneficial properties of ME-609 were also found to be superior to those of Zovirax cream when tested in the standard guinea pig model, representing a primary HSV infection. ME-609 represents a novel treatment principle of recurrent HSV infections and the present paper summarizes the preclinical and early clinical experience of ME-609.
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50. |
- Hertzberg, M., et al.
(författare)
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A transcriptional roadmap to wood formation
- 2001
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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. ; 98:25, s. 14732-14737
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Tidskriftsartikel (refereegranskat)abstract
- The large vascular meristem of poplar trees with its highly organized secondary xylem enables the boundaries between different developmental zones to be easily distinguished. This property of wood-forming tissues allowed us to determine a unique tissue-specific transcript profile for a well defined developmental gradient. RNA was prepared from different developmental stages of xylogenesis for DNA microarray analysis by using a hybrid aspen unigene set consisting of 2,995 expressed sequence tags. The analysis revealed that the genes encoding lignin and cellulose biosynthetic enzymes, as well as a number of transcription factors and other potential regulators of xylogenesis, are under strict developmental stage-specific transcriptional regulation.
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