| 1. |
- Alcorn, J, et al.
(author)
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Basic instrumentation for Hall A at Jefferson Lab
- 2004
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 522:3, s. 294-346
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Journal article (peer-reviewed)abstract
- The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electro-and photo-induced reactions at very high luminosity and good momentum and angular resolution for at least one of the reaction products. The central components of Hall A are two identical high resolution spectrometers, which allow the vertical drift chambers in the focal plane to provide a momentum resolution of better than 2 x 10(-4). A variety of Cherenkov counters, scintillators and lead-glass calorimeters provide excellent particle identification. The facility has been operated successfully at a luminosity well in excess of 10(38) CM-2 s(-1). The research program is aimed at a variety of subjects, including nucleon structure functions, nucleon form factors and properties of the nuclear medium. (C) 2003 Elsevier B.V. All rights reserved.
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| 2. |
- Castro-Tirado, A. J., et al.
(author)
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GRB 030227 : The first multiwavelength afterglow of an INTEGRAL GRB
- 2003
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In: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 411:1, s. 315-319
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Journal article (peer-reviewed)abstract
- We present multiwavelength observations of a gamma-ray burst detected byINTEGRAL (GRB 030227) between 5.3 hours and ~ 1.7days after the event. Here we report the discovery of a dim opticalafterglow (OA) that would not have been detected by many previoussearches due to its faintess (R ~ 23). This OA was seen to declinefollowing a power law decay with index alpha R = -0.95 +/-0.16. The spectral index beta_ opt/NIR yielded -1.25 +/- 0.14. Thesevalues may be explained by a relativistic expansion of a fireball (withp = 2.0) in the cooling regime. We also find evidence for inverseCompton scattering in X-rays.Based on observations with INTEGRAL, an ESA project with instruments andscience data centre funded by ESA member states (especially the PIcountries: Denmark, France, Germany, Italy, Switzerland, Spain), CzechRepublic and Poland, and with the participation of Russia and the USA.Also partially based on observations collected by the Gamma-Ray BurstCollaboration at ESO (GRACE) at the European Southern Observatory, Chile(ESO Large Programme 165.H-0464).
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| 3. |
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| 4. |
- Neusser, A, et al.
(author)
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Superdeformed band at very high spin in Nd-140
- 2004
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In: Physical Review C (Nuclear Physics). - 0556-2813. ; 70:6
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Journal article (peer-reviewed)abstract
- A new high-spin superdeformed band has been discovered in Nd-140(60)80. It was populated in the Zr-96(Ca-48,4n) reaction and investigated using the EUROBALL gamma-ray spectrometer array. The band is observed in the approximate spin range of I=36 to 66. It is associated with shell gaps around Z=60 and at N=80 at large deformation. These gaps produce a pronounced minimum in the calculated total Routhian surfaces at a quadrupole deformation of epsilon(2)=0.45. The new band which lies between the high-deformation bands in the Aapproximate to130 region and the superdeformed bands in Aapproximate to150 nuclei provides insight into the development of the deformation between these two regions. Two possible configurations are suggested involving four neutrons of i(13/2) origin (nu6(4)) and either six protons of h(11/2)/h(9/2) origin (pi5(6)) or five protons of h(11/2)/h(9/2) and one of i(13/2) origin (pi5(5)6(1)).
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| 5. |
- Nyholm, R., et al.
(author)
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Beamline I311 at MAX-LAB : A VUV/soft X-ray undulator beamline for high resolution electron spectroscopy
- 2001
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 467-468, s. 520-524
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Journal article (peer-reviewed)abstract
- We describe a beamline based on a plane-grating monochromator and an end-station designed for high resolution photoemission and photoabsorption spectroscopy on surfaces and interfaces using undulator radiation in the energy range 30 1500 eV. The general design of the beamline is based on a horizontally focusing pre-mirror, an SX-700 type of plane-grating monochromator and re-focusing optics of Kirkpatrick-Baez design.
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| 6. |
- Oberg, M, et al.
(author)
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Subchronic toxicity of Baltic herring oil and its fractions in the rat I: Fractionation and levels of organohalogen pollutants
- 2002
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In: Pharmacology and Toxicology. - : Wiley. - 1600-0773 .- 0901-9928. ; 91:5, s. 220-231
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Journal article (peer-reviewed)abstract
- Baltic herring (Clupea harengus) oil was extracted and fractionated. To examine the contribution to toxicity and biological effects of different halogenated organic pollutants, the herring oil and the fractions were mixed into pelleted food and given to Sprague-Dawley female rats at three levels, corresponding to a human intake of 1.6, 8.2 and 34.4 kg fish per week. Herring oil, its fractions, as well as liver tissues from exposed rats, were analyzed for: eight chlorinated biphenyls, all 2,3,7,8-substituted chlorinated dibenzo-p-dioxins and dibenzofurans, hexachlorocyclohexanes, hexachlorobenzene, 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), DDT-metabolites, three brominated diphenylethers as well as extractable organically bound chlorine and halogenated fatty acids. A bioassay (EROD) was used for measuring the dioxin-like enzyme induction activity. Nordic Sea lodda (Mallotus villosus) oil was used as a nutritionally equivalent control, with much lower levels of halogenated organic pollutants. A full toxicological subchronic examination is reported in the following paper (Stern et al. 2002). In this study, we report that the fractionation procedure resulted in a substantial reduction of most of the pollutants in the triacylglycerol fraction, and a pronounced enrichment of most of the pollutants into the two other fractions. However, all contaminants were present at some levels in all of the fractions. The concentrations of organoltalogens found in this study were representative for Baltic herring during the mid-1990s. Rat liver tissue showed similar residue patterns as the diet, with the exception of chlorinated dibenzo-p-dioxin and dibenzofuran congeners that had a higher liver retention than pesticides, chlorinated biphenyls and brominated diphenylethers.
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| 7. |
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| 9. |
- Ersmark, Tore, et al.
(author)
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Status of the DESIRE project : Geant4 physics validation studies and first results from columbus/ISS radiation simulations
- 2004
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In: IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORD. ; , s. 1540-1544
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Conference paper (other academic/artistic)abstract
- The DESIRE (Dose Estimation by Simulation of the ISS Radiation Environment) project aimes to accurately calculate radiation fluxes and doses to astronauts inside the European Columbus module of the International Space Station using Geant4. Firstly physics benchmark studies have been performed and comparisons made to experimental data and other particle transport programs. This will be followed by a detailed evaluation of the incident radiation fields on the ISS and culminate with the geometry modelling and full-scale flux and dose simulations for the Columbus. Geant4 validation studies are presented here. These concern the angle and energy distribution of particles leaving irradiated targets and of energy depositions in the targets. Comparisons are made between simulations using different Geant4 physics models, experimental data and other particle transport programs. Geant4 using the "Binary Cascade" model for inelastic nucleon reactions performs very well in these comparisons but some issues with other models remain to be resolved if these models are to be used for space radiation shielding applications. Results of Geant4 simulations of the transport of relevant radiation field components through the hull of the Columbus/ISS are also presented.
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| 10. |
- Ersmark, Tore, et al.
(author)
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Status of the DESIRE project : Geant4 physics validation studies and first results from columbus/ISS radiation simulations
- 2004
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In: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 51:4, s. 1378-1384
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Journal article (peer-reviewed)abstract
- The Dose Estimation by Simulation of the ISS Radiation Environment (DESIRE) project aims to accurately calculate radiation fluxes and doses to astronauts inside the European Columbus module of the International Space Station using Geant4. Since Geant4 has not been previously used for this type of application it needs to be validated. This will be followed by a detailed evaluation of the incident radiation fields on ISS and culminate with the geometry modeling and full-scale flux and dose simulations for Columbus. Geant4 validation studies and comparisons to other tools are presented. These concern the angle and energy distributions of particles leaving irradiated targets and of energy depositions in the targets. Comparisons are made between simulations using different Geant4 physics models, experimental data, and other particle transport programs. Geant4 using the Binary Cascade model for inelastic nucleon reactions performs very well in these comparisons, but some issues with other models remain to be resolved if they are to be used for space radiation shielding applications. Results of Geant4 simulations of the transport of some relevant radiation field components through the hull of a simplified model of Columbus are also presented.
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| 11. |
- Franklin, K. A., et al.
(author)
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The influence of active and passive smoking on habitual snoring
- 2004
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In: Am J Respir Crit Care Med. ; 170:7
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Journal article (peer-reviewed)abstract
- The impact of active smoking, passive smoking, and obesity on habitual snoring in the population is mainly unknown. We aimed to study the relationship of habitual snoring with active and passive tobacco smoking in a population-based sample. A total of 15,555 of 21,802 (71%) randomly selected men and women aged 25-54 years from Iceland, Estonia, Denmark, Norway, and Sweden answered a postal questionnaire. Habitual snoring, defined as loud and disturbing snoring at least 3 nights a week, was more prevalent among current smokers (24.0%, p < 0.0001) and ex-smokers (20.3%, p < 0.0001) than in never-smokers (13.7%). Snoring was also more prevalent in never-smokers exposed to passive smoking at home on a daily basis than in never-smokers without this exposure (19.8% vs. 13.3%, p < 0.0001). The frequency of habitual snoring increased with the amount of tobacco smoked. Active smoking and passive smoking were related to snoring, independent of obesity, sex, center, and age. Ever smoking accounted for 17.1% of the attributable risk of habitual snoring, obesity (body mass index >/= 30 kg/m(2)) for 4.3%, and passive smoking for 2.2%. Smoking, both current and ex-smoking, is a major contributor to habitual snoring in the general population. Passive smoking is a previously unrecognized risk factor for snoring among adults.
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| 12. |
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| 15. |
- Holten-Andersen, MN, et al.
(author)
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Measurement of the noncomplexed free fraction of tissue inhibitor of metalloproteinases I in plasma by immunoassay
- 2002
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In: Clinical Chemistry. - 0009-9147. ; 48:8, s. 1305-1313
-
Journal article (peer-reviewed)abstract
- Background: We previously found differences in total concentrations of tissue inhibitor of metalloproteinases 1 (TIMP-1) in plasma from donors and cancer patients. Because TIMP-1 can exist in more than one molecular form, a new immunoassay to specifically detect free TIMP-1 was developed and concentrations were determined in plasma from healthy donors and colorectal cancer (CRC) patients. Methods: We established and validated an immunoassay for the specific measurement of free TIMP-1 that uses a polyclonal anti-TIMP-1 antibody for capture and a monoclonal anti-TIMP-1 antibody that binds only free TIMP-1 for detection of antigen. Plasma samples from healthy donors and CRC patients were assayed for free TIMP-1. Total TIMP-1 was measured by our previously published assay. Results: The mean (SD) concentrations of free TIMP-1 were similar in citrate [55.5 (11.5) mug/L] and EDTA plasma [58.9 (13.3) mug/L] from 76 donors (r(2) = 0.82). In 154 donors, the ratio of free TIMP-1 [mean (SD), 64.5 (18.0) mug/L] to total TIMP-1 [83.8 (19.8) mug/L] in EDTA plasma was 0.77. Plasma concentrations of free and total TIMP-1 correlated significantly to age (free, r(2) = 0.19; total, r(2) = .0.27; P < 0.0001), increasing 50% over an age span of 45 years. Free and total TIMP-1 were significantly increased in CRC patients (P < 0.0001), whereas the ratio of free to total TIMP-1 (mean, 0.58) was significantly lower than in donors. Conclusions: Most of the TIMP-1 in donor plasma is present in its free form, and free TIMP-1 increases with age. Free and total TIMP-1 are increased in CRC patient plasma, but the ratio of free to total TIMP-1 is significantly lower in these patients than in donors. (C) 2002 American Association for Clinical Chemistry.
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| 16. |
- Holten-Andersen, MN, et al.
(author)
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Total levels of tissue inhibitor of metalloproteinases 1 in plasma yield high diagnostic sensitivity and specificity in patients with colon cancer
- 2002
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In: Clinical Cancer Research. - 1078-0432. ; 8:1, s. 156-164
-
Journal article (peer-reviewed)abstract
- Purpose: The purpose of this study was to measure total levels of tissue inhibitor of metalloproteinases (TIMP-1) by ELISA in plasma from blood donors, patients with inflammatory bowel disease (IBD), and patients with cancer and to correlate the results to patient diagnosis. Experimental Design: Total TIMP-1 plasma levels were measured by ELISA in blood samples from two different blood donor populations from IBD patients, and preoperative samples from patients with primary colon cancer (CC), rectal cancer (RC), or breast cancer. Results: There were no significant differences in plasma TIMP-1 levels between healthy donors and 1131) or breast cancer patients, whereas patients with CC or RC had significantly elevated TIMP-1 levels. Total TIMP-1 levels identified patients with CC with a sensitivity of 63% at 98% specificity, patients with early CC (Dukes' A+B) with a sensitivity of 56% at 98% specificity, and patients with right-sided CC with a sensitivity of 72% at 98% specificity. Combining carcinoembryonic antigen and TIMP-1 measurements increased the sensitivities obtained from TIMP-1 measurements alone. Conclusions: TIMP-1 was significantly elevated in plasma from CC and RC patients, including those with early-stage disease. Sensitivity and specificity were both sufficiently high to consider TIMP-1 as a marker for the early identification of CC patients, in particular, those with right-sided CC.
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| 17. |
- Häggström, S, et al.
(author)
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Effects of finasteride on vascular endothelial growth factor.
- 2002
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In: Scandinavian Journal of Urology and Nephrology. - : Informa UK Limited. - 0036-5599 .- 1651-2065. ; 36:3, s. 182-7
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Finasteride has been shown to reduce prostate bleeding in patients with benign prostatic hyperplasia (BPH). The mechanisms behind this are not known, but it has been suggested that finasteride reduces bleeding by inhibiting angiogenesis in the prostate. Studies in animals have shown that castration rapidly induces involution of the prostate vasculature, and androgen-stimulated prostate growth may be angiogenesis dependent. The objective of this study was to explore the response to finasteride on the vasculature and the expression of vascular endothelial growth factor (VEGF), a potent regulatory factor of angiogenesis in human prostate tissue.MATERIAL AND METHODS: Patients with BPH were randomly assigned to 3 months of treatment either with finasteride (5 mg/day) or placebo before undergoing transurethral resection of the prostate (TURP). Prostate tissue VEGF expression was quantified by Western blot and the vascular density determined in Factor VIII immunostained tissue sections. Serum concentrations of VEGF were measured with ELISA technique.RESULTS: Patients treated with finasteride (n = 15) showed a decrease in prostate tissue VEGF(165) expression compared with placebo (n = 13) treated patients (p < 0.05), but the vascular density and the serum VEGF levels were unaffected.CONCLUSIONS: This study shows that finasteride treatment decreases VEGF expression in the human prostate.
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| 18. |
- Jensen, J.A.D., et al.
(author)
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Electrochemical deposition of buried contacts in high-efficiency crystalline silicon photovoltaic cells
- 2003
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In: Journal of the Electrochemical Society. - : The Electrochemical Society. - 0013-4651 .- 1945-7111. ; 150:1
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Journal article (peer-reviewed)abstract
- This article reports on a newly developed method for electrochemical deposition of buried Cu contacts in Si-based photovoltaic (PV) cells. Contact grooves, 20 µm wide by 40 µm deep, were laser-cut into Si PV cells, hereafter applied with a thin electroless NiP base and subsequently filled with Cu by electrochemical deposition at a rate of up to 10 µm per min. With the newly developed process, void-free, superconformal Cu-filling of the laser-cut grooves was observed by scanning electron microscopy and focused ion beam techniques. The Cu microstructure in grooves showed both bottom and sidewall texture, with a grain-size decreasing from the center to the edges of the buried Cu contacts and a pronounced lateral growth outside the laser-cut grooves. The measured specific contact resistances of the buried contacts was better than the production standard. Overall performance of the new PV cells was equal to the production standard with measured efficiencies up to 16.9%.
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| 19. |
- Jensen, N, et al.
(author)
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CoVASE - Collaborative Visualization for Constructivist Learning
- 2003
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In: Designing for Change in Networked Learning Environments. ; , s. 249-253
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Conference paper (other academic/artistic)abstract
- The paper specifies CoVASE, a software for teachers to create and view networked learning environments (VE). Students carry out virtual experiments in CoVASE, at the same time and from different places. They use the same tools and work on the same scientific problems as researchers do. Teachers create a motivating, demanding, and authentic interaction between learners and real-world problems, a premise for constructivist learning (CL). CoVASE generates and displays the result of a numerical simulation in parallel of its progress on distributed 3D graphic viewers, steered by users in real-time. VEs mediate communication between users, deictic elements, and display. Researchers and students have evaluated the predecessors of CoVASE with good results. A field study is planned for 2003.
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| 20. |
- Jensen, N., et al.
(author)
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CoVASE: Collaborative Visualization for Constructivist Learning
- 2003
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In: Computer Support for Collaborative Learning 2003.
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Conference paper (peer-reviewed)abstract
- The paper specifies CoVASE, a software for teachers to create and view networked learning environments (VE). Students carry out virtual experiments in CoVASE, at the same time and different places. They use the same tools and work on the same scientific p
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| 21. |
- Jensen, N, et al.
(author)
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Development of a Virtual Laboratory System for Science Education and the Study of Collaborative Action
- 2004
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In: Proceedings of AACE ED Media Conference 2004. - 1880094533
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Conference paper (other academic/artistic)abstract
- The paper specifies the development of a toolkit to run synthetic science laboratories. The aim was to facilitate collaborative experimenting for problem-based learning in a virtual lab. The goal was to demonstrate virtual experimenting by use of interactive 3D visualization and simulation. Technology was developed over six years and in part designed in explicit accordance to didactic models. For tests, we built a virtual lab that comprised media tools and complex computer simulations, and we evaluated it with promising results. Students used data from meteorology and experimented together. Generally, they enjoyed using the system and collaborated in a motivated way. We identified which tools they preferred. The paper indicates ways to improve the design of virtual labs by use of our toolkit.
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| 25. |
- Periale, L., et al.
(author)
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The development of gaseous detectors with solid photocathodes for low-temperature applications
- 2004
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In: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 535:02-jan, s. 517-522
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Journal article (peer-reviewed)abstract
- There are several applications and studies in fundamental research, which require the detection of VUV light at cryogenic temperatures. For these applications, we have developed and successfully tested special designs of gaseous detectors with solid photocathodes able to operate at low temperatures: sealed gaseous detectors with MgF2 windows and windowless detectors. We have experimentally demonstrated that both primary and secondary (due to the avalanche multiplication inside liquids) scintillation light can be recorded by photosensitive gaseous detectors. The results of this work may allow one to significantly improve the operation of some noble liquid TPCs.
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