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1.	Adcox, K, et al. (författare) PHENIX detector overview 2003 Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 469-479 Tidskriftsartikel (refereegranskat)abstract The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions. A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon. Designing for the needs of the heavy-ion and polarized-proton programs has produced a detector with unparalleled capabilities. PHENIX measures electron and muon pairs, photons, and hadrons with excellent energy and momentum resolution. The detector consists of a large number of subsystems that are discussed in other papers in this volume. The overall design parameters of the detector are presented. (C) 2002 Elsevier Science B.V. All rights reserved.
2.	Adler, SS, et al. (författare) Double helicity asymmetry in inclusive midrapidity pi(0) production for polarized p+p collisions at root s=200 GeV 2004 Ingår i: Physical Review Letters. - 1079-7114. ; 93:20: 202002 Tidskriftsartikel (refereegranskat)abstract We present a measurement of the double longitudinal spin asymmetry in inclusive pi(0) production in polarized proton-proton collisions at roots=200 GeV. The data were taken at the Relativistic Heavy Ion Collider with average beam polarizations of 0.27. The measurements are the first in a program to study the longitudinal spin structure of the proton, using strongly interacting probes, at collider energies. The asymmetry is presented for transverse momenta 1-5 GeV/c at midrapidity, where next-to-leading-order perturbative quantum chromodynamic (NLO pQCD) calculations well describe the unpolarized cross section. The observed asymmetry is small and is compared to a NLO pQCD calculation with a range of polarized gluon distributions.
3.	Adler, SS, et al. (författare) Bose-Einstein correlations of charged pion pairs in Au+Au collisions at root(NN)-N-s = 200 GeV 2004 Ingår i: Physical Review Letters. - 1079-7114. ; 93:15 Tidskriftsartikel (refereegranskat)abstract Bose-Einstein correlations of identically charged pion pairs were measured by the PHENIX experiment at midrapidity in Au+Au collisions at roots(NN)=200 GeV. The Bertsch-Pratt radius parameters were determined as a function of the transverse momentum of the pair and as a function of the centrality of the collision. Using the standard core-halo partial Coulomb fits, and a new parametrization which constrains the Coulomb fraction as determined from the unlike-sign pion correlation, the ratio R-out/R-side is within 0.8-1.1 for 0.25<<1.2 GeV/c. The centrality dependence of all radii is well described by a linear scaling in N-part(1/3), and R-out/R-side for similar to0.45 GeV/c is approximately constant at unity as a function of centrality.
4.	Adler, SS, et al. (författare) Elliptic flow of identified hadrons in Au+Au collisions at root s(NN)=200 GeV 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:18: 182301 Tidskriftsartikel (refereegranskat)abstract The anisotropy parameter (v(2)), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at roots(NN)=200 GeV for identified and inclusive charged particle production at central rapidities (eta<0.35) with respect to the reaction plane defined at high rapidities (eta=3-4 ). We observe that the v(2) of mesons falls below that of (anti)baryons for p(T)>2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.
5.	Adler, SS, et al. (författare) J/psi production from proton-proton collisions at root s=200 GeV 2004 Ingår i: Physical Review Letters. - 1079-7114. ; 92:5 Tidskriftsartikel (refereegranskat)abstract J/psi production has been measured in proton-proton collisions at roots=200 GeV over a wide rapidity and transverse momentum range by the PHENIX experiment at the Relativistic Heavy Ion Collider. Distributions of the rapidity and transverse momentum, along with measurements of the mean transverse momentum and total production cross section are presented and compared to available theoretical calculations. The total J/psi cross section is 4.0+/-0.6(stat)+/-0.6(syst)+/-0.4(abs) mub. The mean transverse momentum is 1.80+/-0.23(stat)+/-0.16(syst) GeV/c.
6.	Adler, SS, et al. (författare) J/psi production in Au-Au collisions at root s(NN)=200 GeV 2004 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 69:1 Tidskriftsartikel (refereegranskat)abstract First results on charm quarkonia production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The yield of J/psi's measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au-Au reactions at roots(NN) = 200 GeV is analyzed as a function of collision centrality. For this analysis we have studied 49.3x10(6) minimum bias Au-Au reactions. We present the J/psi invariant yield dN/dy for peripheral and midcentral reactions. For the most central collisions where we observe no signal above background, we quote 90% confidence level upper limits. We compare these results with our J/psi measurement from proton-proton reactions at the same energy. We find that our measurements are not consistent with models that predict strong enhancement relative to binary collision scaling.
7.	Adler, SS, et al. (författare) Midrapidity neutral-pion production in proton-proton collisions at root s 200 GeV 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:24: 241803 Tidskriftsartikel (refereegranskat)abstract The invariant differential cross section for inclusive neutral-pion production in p+p collisions at roots=200 GeV has been measured at midrapidity (eta<0.35) over the range 1
8.	Adler, SS, et al. (författare) Scaling properties of proton and antiproton production in root s(NN)=200 GeV Au+Au collisions 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:17: 172301 Tidskriftsartikel (refereegranskat)abstract We report on the yield of protons and antiprotons, as a function of centrality and transverse momentum, in Au+Au collisions at rootS(NN)=200 GeV measured at midrapidity by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider. In central collisions at intermediate transverse momenta (1.5
9.	Adler, SS, et al. (författare) Suppressed pi(0) production at large transverse momentum in central Au plus Au collisions at root s(NN)=200 GeV 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:7: 072301 Tidskriftsartikel (refereegranskat)abstract Transverse momentum spectra of neutral pions in the range 1
10.	Adcox, K, et al. (författare) Centrality dependence of the high (PT) charged hadron suppression in Au+Au collisions at root s(NN)=130 GeV 2003 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 561:1-2, s. 82-92 Tidskriftsartikel (refereegranskat)abstract PHENIX has measured the centrality dependence of charged hadron p(T) spectra from Au +An collisions at root(s)NN = 130 GeV The truncated mean p(T) decreases with centrality for p(T) > 2 GeV/c, indicating an apparent reduction of the contribution from hard scattering to high p(T) hadrdn production. For central collisions the yield at high p(T) is shown to be suppressed compared to binary nucleon-nucleon collision scaling of p + p, data. This suppression is monotonically increasing with centrality, but most of the change occurs below 30% centrality, i.e., for collisions with less than similar to140 participating nucleons. The observed p(T) and centrality dependence is consistent with the particle production predicted by models including hard scattering and subsequent energy loss of the scattered partons in the dense matter created in the collisions. (C) 2003 Published by Elsevier Science B.V.
11.	Adcox, K, et al. (författare) Event-by-event fluctuations in mean p(T) and mean E(T) in root s(NN)=130 GeVAu+Au collisions 2002 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 66:2 Tidskriftsartikel (refereegranskat)abstract Distributions of event-by-event fluctuations of the mean transverse momentum and mean transverse energy near mid-rapidity have been measured in Au+Au collisions at roots(NN)=130 GeV at the Relativistic Heavy-Ion Collider. By comparing the distributions to what is expected for statistically independent particle emission, the magnitude of nonstatistical fluctuations in mean transverse momentum is determined to be consistent with zero. Also, no significant nonrandom fluctuations in mean transverse energy are observed. By constructing a fluctuation model with two event classes that preserve the mean and variance of the semi-inclusive p(T) or e(T) spectra, we exclude a region of fluctuations in roots(NN)=130 GeV Au+Au collisions.
12.	Adcox, K, et al. (författare) Flow Measurements via Two-Particle Azimuthal Correlations in Au+Au Collisions at sqrt[sNN]=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 89 Tidskriftsartikel (refereegranskat)abstract Two-particle azimuthal correlation functions are presented for charged hadrons produced in Au+Au collisions at the Relativistic Heavy Ion Collider (sqrt[sNN]=130 GeV). The measurements permit determination of elliptic flow without event-by-event estimation of the reaction plane. The extracted elliptic flow values (v2) show significant sensitivity to both the collision centrality and the transverse momenta of emitted hadrons, suggesting rapid thermalization and relatively strong velocity fields. When scaled by the eccentricity of the collision zone ε, the scaled elliptic flow shows little or no dependence on centrality for charged hadrons with relatively low pT. A breakdown of this ε scaling is observed for charged hadrons with pT >1.0 GeV/c.
13.	Adcox, K, et al. (författare) Measurement of Lambda and (Lambda)over-bar particles in Au plus Au collisions at root s(NN)=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 89:9 Tidskriftsartikel (refereegranskat)abstract We present results on the measurement of Lambda and (&ULambda;) over bar production in Au+Au collisions at roots(NN)=130 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. The transverse momentum spectra were measured for minimum bias and for the 5% most central events. The (&ULambda;) over bar/Lambda ratios are constant as a function of p(T) and the number of participants. The measured net Lambda density is significantly larger than predicted by models based on hadronic strings (e.g., HIJING) but in approximate agreement with models which include the gluon-junction mechanism.
14.	Adcox, K, et al. (författare) Measurement of single electrons and implications for charm production in Au+Au collisions at root(NN)-N-S=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 88:19 Tidskriftsartikel (refereegranskat)abstract Transverse momentum spectra of electrons from Au+Au collisions at roots(NN) = 130 GeV have been measured at midrapidity by the PHENIX experiment at the Relativistic Heavy Ion Collider. The spectra show an excess above the background from photon conversions and light hadron decays. The electron signal is consistent with that expected from semileptonic decays of charm. The yield of the electron signal dN(e)/dy for p(T) > 0.8 GeV/c is 0.025 +/- 0.004(stat) +/- 0.010( syst) in central collisions, and the corresponding charm cross section is 380 +/- 60(stat) +/- 200(syst ) mub per binary nucleon-nucleon collision.
15.	Adcox, K, et al. (författare) Net charge fluctuations in Au+Au interactions root s(NN)=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 89 Tidskriftsartikel (refereegranskat)abstract Data from Au+ Au interactions at s(NN)=130 GeV, obtained with the PHENIX detector at the Relativistic Heavy-Ion Collider, are used to investigate local net charge fluctuations among particles produced near midrapidity. According to recent suggestions, such fluctuations may carry information from the quark-gluon plasma. This analysis shows that the fluctuations are dominated by a stochastic distribution of particles, but are also sensitive to other effects, like global charge conservation and resonance decays.
16.	Adcox, K, et al. (författare) Suppression of hadrons with large transverse momentum in central Au+Au collisions at root s(NN)=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 88:2 Tidskriftsartikel (refereegranskat)abstract Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 Gev/c < P-T < 5 GeV/c have been measured by the PHENIX experiment at RHIC in Au + Au collisions at rootS(NN) = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p + p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p + p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies.
17.	Adcox, K, et al. (författare) Transverse-mass dependence of two-pion correlations in Au+Au collisions at root(NN)-N-S=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 88:19 Tidskriftsartikel (refereegranskat)abstract Two-pion correlations in roots(NN) = 130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k(T) by the PHENIX experiment at RHIC. The k(T) dependent transverse radii are similar to results from heavy-ion collisions at roots(NN) = 4.1 , 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R-out/R-side) is consistent with unity and independent of k(T) .
18.	Pfaller, M.A., et al. (författare) Twelve years of fluconazole in clinical practice : Global-trends in species distribution and fluconazole susceptibility of bloodstream isolates of Candida 2004 Ingår i: Clinical Microbiology and Infection. - : Elsevier BV. - 1198-743X .- 1469-0691. ; 10:SUPPL. 1, s. 11-23 Tidskriftsartikel (refereegranskat)abstract We determined the species distribution and in-vitro susceptibility of 6082 bloodstream infection (BSI) isolates of Candida spp. collected from 250 medical centres in 32 nations over a 10-year period from 1992 through 2001. The species included 3401 C. albicans, 984 C. glabrata, 796 C. parapsilosis, 585 C. tropicalis, 153 C. krusei, 67 C. lusitaniae, 48 C. guilliermondii, 10 C. famata, 10 C. kefyr, six C. pelliculosa, five C. rugosa, four C. lipolytica, three C. dubliniensis, three C. inconspicua, two C. sake and one isolate each of C. lambica, C. norvegensis and C. zeylanoides. Minimum inhibitory concentration determinations were made using the National Committee for Clinical Laboratory Standards reference broth microdilution method. Variation in the rank order and frequency of the different species of Candida was observed over time and by geographic area. The proportion of BSI due to C. albicans and C. glabrata increased and C. parapsilosis decreased over time in Canada, the USA and Europe. C. glabrata was an infrequent cause of BSI in Latin America and the Asia-Pacific region. Very little variation in fluconazole susceptibility was observed among isolates of C. albicans, C. tropicalis and C. parapsilosis. These species accounted for 78% of all BSI and remained highly susceptible (91-100% susceptible) to fluconazole from 1992 to 2001 irrespective of geographic origin. The prevalence of fluconazole resistance among C. glabrata isolates was variable both over time and among the various countries and regions. Resistance to fluconazole among C. glabrata isolates was greatest in the USA and varied by US census region (range 0-23%). These observations are generally encouraging relative to the sustained usefulness of fluconazole as a systemically active antifungal agent for the treatment of candida BSI. © 2004 Copyright by the European Society of Clinical Microbiology and Infectious Diseases.
19.	Okazaki, Y, et al. (författare) Analysis of the mouse transcriptome based on functional annotation of 60,770 full-length cDNAs 2002 Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 420:6915, s. 563-573 Tidskriftsartikel (refereegranskat)
20.	Beral, V, et al. (författare) Alcohol, tobacco and breast cancer - collaborative reanalysis of individual data from 53 epidemiological studies, including 58515 women with breast cancer and 95067 women without the disease 2002 Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 87, s. 1234-45 Tidskriftsartikel (refereegranskat)abstract Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58515 women with invasive breast cancer and 95067 controls from 53 studies. Relative risks of breast cancer were estimated, after stratifying by study, age, parity and, where appropriate, women's age when their first child was born and consumption of alcohol and tobacco. The average consumption of alcohol reported by controls from developed countries was 6.0 g per day, i.e. about half a unit/drink of alcohol per day, and was greater in ever-smokers than never-smokers, (8.4 g per day and 5.0 g per day, respectively). Compared with women who reported drinking no alcohol, the relative risk of breast cancer was 1.32 (1.19 - 1.45, P < 0.00001) for an intake of 35 - 44 g per day alcohol, and 1.46 (1.33 - 1.61, P < 0.00001) for greater than or equal to 45 g per day alcohol. The relative risk of breast cancer increased by 7.1% (95% CI 5.5-8.7%; P<0.00001) for each additional 10 g per day intake of alcohol, i.e. for each extra unit or drink of alcohol consumed on a daily basis. This increase was the same in ever-smokers and never-smokers (7.1 % per 10 g per day, P < 0.00001, in each group). By contrast, the relationship between smoking and breast cancer was substantially confounded by the effect of alcohol. When analyses were restricted to 22 255 women with breast cancer and 40 832 controls who reported drinking no alcohol, smoking was not associated with breast cancer (compared to never-smokers, relative risk for ever-smokers= 1.03, 95% CI 0.98 - 1.07, and for current smokers=0.99, 0.92 - 1.05). The results for alcohol and for tobacco did not vary substantially across studies, study designs, or according to 15 personal characteristics of the women; nor were the findings materially confounded by any of these factors. If the observed relationship for alcohol is causal, these results suggest that about 4% of the breast cancers in developed countries are attributable to alcohol. In developing countries, where alcohol consumption among controls averaged only 0.4 g per day, alcohol would have a negligible effect on the incidence of breast cancer. In conclusion, smoking has little or no independent effect on the risk of developing breast cancer; the effect of alcohol on breast cancer needs to be interpreted in the context of its beneficial effects, in moderation, on cardiovascular disease and its harmful effects on cirrhosis and cancers of the mouth, larynx, oesophagus and liver. (C) 2002 Cancer Research UK.
21.	Yu, H.Y., et al. (författare) Current enhancement with alternating gate voltage in the Coulomb blockade regime of a single wall carbon nanotube 2004 Ingår i: Applied Physics A. - : Springer Science and Business Media LLC. - 0947-8396 .- 1432-0630. ; 79, s. 1613-1615 Tidskriftsartikel (refereegranskat)abstract We investigated the current–voltage characteristics of a carbon nanotube in a single electron transistor structure with alternating gate voltage. A continuous current enhancement effect with increasing frequency of the applied gate voltage up to 13 MHz is reported. Assuming that I=nef, more than 1000 electrons are driven to flow across the source–drain channel at VDS=100 mV, 13 MHz of gate voltage (Vp-p=2 V) and T=1.8 K. The continuous current enhancement is explained by the broadening effect of the discrete energy levels of the finite-length carbon nanotube.
22.	Ahmed, M., et al. (författare) Search for the lepton-family-number nonconserving decay μ +→e +γ 2002 Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 65:11 Tidskriftsartikel (refereegranskat)abstract The MEGA experiment, which searched for the muon- and electron-number violating decay μ +→e + γ, is described. The spectrometer system, the calibrations, the data taking procedures, the data analysis, and the sensitivity of the experiment are discussed. The most stringent upper limit on the branching ratio, B(μ + →e + γ)<1.2×10 -11 with 90% confidence, is derived from a likelihood analysis.
23.	Lindenberg, A. M, et al. (författare) Time-resolved X-ray diffraction from coherent phonons during a laser-induced phase transition 2000 Ingår i: Physical Review Letters. - 1079-7114. ; 84:1, s. 111-114 Tidskriftsartikel (refereegranskat)abstract Time-resolved x-ray diffraction with picosecond temporal resolution is used to observe scattering from impulsively generated coherent acoustic phonons in laser-excited InSb crystals. The observed frequencies and damping rates are in agreement with a model based on dynamical diffraction theory coupled to analytic solutions for the laser-induced strain profile. The results are consistent with a 12 ps thermal electron-acoustic phonon coupling time together with an instantaneous component from the deformation-potential interaction. Above a critical laser fluence, we show that the first step in the transition to a disordered state is the excitation of large amplitude, coherent atomic motion.
24.	Niemann, C., Rosmej, F.B., Tauschwitz, A., Neff, S., Penache, D., Birkner, R., Constantin, C., Knobloch, R., Presura, R., Hoffmann, D.H.H., Yu, S.S., Lee, R.W. (författare) pectroscopic density and temperature measurements and modelling of a discharge plasma for neutralized ion-beam transport. 2003 Ingår i: J.Physics D-Appl. Physics. ; 36, s. 2102-9 Tidskriftsartikel (refereegranskat)
25.	Ward, D., et al. (författare) Band Structure of 68Ge 2001 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 63:1 Tidskriftsartikel (refereegranskat)abstract The nucleus Ge-68 has been studied by gamma-ray spectroscopy following its population at high spin in the reaction Ca-40(S-32,4p) Ge-68. The reaction channel was selected with the Microball array and gamma rays were detected with the Gammasphere array. The level scheme is very complex, reflecting the many different, and presumably mixed, excitation modes in this nucleus. Nevertheless, there appear to be some simplifications in the spin range above 18 (h) over bar where we have identified a superdeformed band and several terminating bands. The results are compared with a cranked Nilsson-Strutinsky model without pairing.
26.	Yoon, Y. J., et al. (författare) Effect of p-type buffer layer on the properties of GaMnAs ferromagnetic semiconductors 2004 Ingår i: Journal of the Korean Physical Society. - 0374-4884 .- 1976-8524. ; 45:SUPPL., s. S720-S723 Tidskriftsartikel (refereegranskat)abstract We have studied the magnetic and transport properties of Ga 1-xMn xAs epilayers grown either on undoped or on p-type doped GaAs buffer layer. The temperature dependence of the resistivity at zero magnetic field reveals that the Curie temperature (T C) in the Ga 1-xMn xAs layer grown on p-type doped GaAs buffer is slightly higher than that observed in the layer grown on undoped GaAs buffer. The magnetic and transport properties of the two samples show significant differences when they are placed in a magnetic field. In SQUID measurements, the Ga 1-xMn xAs layer grown on p-type buffer shows a larger coercive field and much slower decay of remanent magnetization than the layer grown on undoped buffer. This robust magnetic behavior observed in the doped sample is discussed in terms of the increase of free carrier concentration in the system arising from p-type doping in the buffer layer.
27.	Zetterling, Carl-Mikael, et al. (författare) Challenges for High Temperature Silicon Carbide Electronics 2003 Ingår i: Materials Research Society Symposium - Proceedings. - San Francisco, CA. ; , s. 15-25 Konferensbidrag (refereegranskat)abstract Silicon carbide has been proposed as an excellent material for high-frequency, high-power and high-temperature electronics. High power and high frequency applications have been pursued for quite some time in SiC with a great deal of success in terms of demonstrated devices. However, self-heating problems due to the much higher power densities that result when ten times higher electrical fields are used inside the devices needs to be addressed. High-temperature electronics has not yet experienced as much attention and success, possibly because there is no immediate market. This paper will review some of the advances that have been made in high-temperature electronics using silicon carbide, starting from process technology, continuing with device design, and finishing with circuit examples. For process technology, one of the biggest obstacles is long-term stable contacts. Several device structures have been electrically characterized at high temperature (BJTs and FETs) and will be compared to surface temperature measurements and physical device simulation. Finally some proposed circuit topologies as well as novel solutions will be presented.
28.	Berenbaum, S, et al. (författare) Consensus statement on 21-hydroxylase deficiency from the European Society for Paediatric Endocrinology and the Lawson Wilkins Pediatric Endocrine Society 2002 Ingår i: Hormone research. - : S. Karger AG. - 0301-0163. ; 58:4, s. 188-195 Tidskriftsartikel (refereegranskat)
29.	Cornelissen, C, et al. (författare) Global change and arctic ecosystems : is lichen decline a function of increases in vascular plant biomass? 2001 Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 89:6, s. 984-994 Tidskriftsartikel (refereegranskat)abstract 1 Macrolichens are important for the functioning and biodiversity of cold northern ecosystems and their reindeer-based cultures and economics. 2 We hypothesized that, in climatically milder parts of the Arctic, where ecosystems have relatively dense plant canopies, climate warming and/or increased nutrient availability leads to decline in macrolichen abundance as a function of increased abundance of vascular plants. In more open high-arctic or arctic-alpine plant communities such a relationship should be absent. To test this, we synthesized cross-continental arctic vegetation data from ecosystem manipulation experiments simulating mostly warming and increased nutrient availability, and compared these with similar data from natural environmental gradients. 3 Regressions between abundance or biomass of macrolichens and vascular plants were consistently negative across the subarctic and mid-arctic experimental studies. Such a pattern did not emerge in the coldest high-arctic or arctic-alpine sites. The slopes of the negative regressions increased across 10 sites as the climate became milder (as indicated by a simple climatic index) or the vegetation denser (greater site above-ground biomass). 4 Seven natural vegetation gradients in the lower-altitude sub- and mid-arctic zone confirmed the patterns seen in the experimental studies, showing consistent negative relationships between abundance of macrolichens and vascular plants. 5 We conclude that the data supported the hypothesis. Macrolichens in climatically milder arctic ecosystems may decline if and where global changes cause vascular plants to increase in abundance. 6 However, a refining of our findings is needed, for instance by integrating other abiotic and biotic effects such as reindeer grazing feedback on the balance between vascular plants and lichens.
30.	Lee, S., et al. (författare) Effect of be doping on the properties of GaMnAs ferromagnetic semiconductors 2003 Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 93:10 3, s. 8307-8309 Tidskriftsartikel (refereegranskat)abstract The effect of Be doping on the properties of GaMnAs ferromagnetic semiconductors was analyzed. The samples were characterized using SQUID and magnetotransport measurements. The observed increase in the critical temperature in Ga 1-xMn xAs for the low range of x can be explained by the increase of free carrier concentrations in the system arising from Be doping.
31.	Svensson, C. E., et al. (författare) Collective rotational motion in the N=Z nucleus 36Ar 2001 Ingår i: Nuclear Physics A. - 0375-9474. ; 682:1-4, s. 1-11 Tidskriftsartikel (refereegranskat)abstract A superdeformed rotational band has been identified in the N = Z nucleus 36Ar, firmly linked to known low-spin states, and observed to its high-spin termination at Iπ = 16+. Lifetime measurements by the Doppler shift attenuation method establish a large low-spin deformation (β2 ≈ 0.46) and a decrease in the collectivity as the band approaches termination. Comparisons with cranked Nilsson-Strutinsky and large-scale spherical shell model calculations lead to a consistent description of the band based on a configuration in which four particles are promoted to the pf shell. With two major shells active for both protons and neutrons, yet a valence space dimension small enough to be approached from the shell model perspective, this band offers an excellent opportunity to investigate the microscopic structure of collective rotational motion in nuclei.
32.	Svensson, C. E., et al. (författare) Superdeformation in the N = z Nucleus 36Ar : Experimental, deformed mean field, and spherical shell model descriptions 2000 Ingår i: Physical Review Letters. - 0031-9007. ; 85:13, s. 2693-2696 Tidskriftsartikel (refereegranskat)abstract A superdeformed rotational band has been identified in 36Ar, linked to known low-spin states, and observed to its high-spin termination at Iπ = 16+. Cranked Nilsson-Strutinsky and spherical shell model calculations assign the band to a configuration in which four pf-shell orbitals are occupied, leading to a low-spin deformation β2 ≈ 0.45. Two major shells are active for both protons and neutrons, yet the valence space remains small enough to be confronted with the shell model. This band thus provides an ideal case to study the microscopic structure of collective rotational motion.
33.	Asztalos, S. J., et al. (författare) Isotopic yields of neutron-rich nuclei from deep-inelastic reactions 2000 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 6101:1 Tidskriftsartikel (refereegranskat)abstract We follow up on our earlier work involving a light projectile (Ca-48) to populate high spin states in neutron-rich nuclei with results from experiments involving a heavier projectile (Sm-154) fur the purposes of studying isotopic yields. These yields, which in some cases were mensurable down to a level of 0.1 of the total reaction cross section, are presented from three separate reactions. A trend in the isotopic yields towards N/Z equilibration is observed in one experiment having a large disparity in N/Z ratios between the projectile and target. In the two other reactions, where the N/Z driving force is less pronounced, the yields are instead clustered around the projectile and target nuclei. We present correlated projectilelike and targetlike fragment isotopic yields derived from gamma-gamma coincidences, a technique that enables one to partition the yield of an isotope according to the amount of neutron evaporation. Using this method we find that for the zero-neutron evaporation channel transfer occurs predominantly into the light fragment, consistent with the nature of the deep-inelastic mechanism. We further find that multiple-neutron evaporation contributes substantially to the yields of the isotopes.
34.	Berenbaum, S, et al. (författare) Consensus statement on 21-hydroxylase deficiency from the Lawson Wilkins Pediatric Endocrine Society and the European Society for Paediatric Endocrinology 2002 Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 87:9, s. 4048-4053 Tidskriftsartikel (refereegranskat)
35.	Cho, H., et al. (författare) High density plasma via hole etching in SiC 2001 Ingår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films. - : American Vacuum Society. - 0734-2101 .- 1520-8559. ; 19:4, s. 1878-1881 Tidskriftsartikel (refereegranskat)abstract Throughwafer vias up to 100 mum deep were formed in 4H-SiC substrates by inductively coupled plasma etching with SF6/O-2 at a controlled rate of similar to0.6 mum min(-1) and use of Al masks. Selectivities of > 50 for SiC over Al were achieved. Electrical (capacitance-voltage: current-voltage) and chemical (Auger electron spectroscopy) analysis techniques showed that the etching produced only minor changes in reverse breakdown voltage, Schottky barrier height, and near surface stoichiometry of the SiC and had high selectivity over common frontside metallization. The SiC etch rate was a strong function of the incident ion energy during plasma exposure. This process is attractive for power SiC transistors intended for high current, high temperature applications and also for SiC micromachining.
36.	Crabtree, Judy S, et al. (författare) Of mice and MEN1 : Insulinomas in a conditional mouse knockout. 2003 Ingår i: Molecular and Cellular Biology. - 0270-7306 .- 1098-5549. ; 23:17, s. 6075-6085 Tidskriftsartikel (refereegranskat)abstract Patients with multiple endocrine neoplasia type 1 (MEN1) develop multiple endocrine tumors, primarily affecting the parathyroid, pituitary, and endocrine pancreas, due to the inactivation of the MEN1 gene. A conditional mouse model was developed to evaluate the loss of the mouse homolog, Men1, in the pancreatic beta cell. Men1 in these mice contains exons 3 to 8 flanked by loxP sites, such that, when the mice are crossed to transgenic mice expressing cre from the rat insulin promoter (RIP-cre), exons 3 to 8 are deleted in beta cells. By 60 weeks of age, >80% of mice homozygous for the floxed Men1 gene and expressing RIP-cre develop multiple pancreatic islet adenomas. The formation of adenomas results in elevated serum insulin levels and decreased blood glucose levels. The delay in tumor appearance, even with early loss of both copies of Men1, implies that additional somatic events are required for adenoma formation in beta cells. Comparative genomic hybridization of beta cell tumor DNA from these mice reveals duplication of chromosome 11, potentially revealing regions of interest with respect to tumorigenesis.
37.	Jorgensen, N, et al. (författare) Trends in male reproductive disorders - General discussion 2001 Ingår i: APMIS. - 0903-4641. ; 109, s. S74-S79 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
38.	Kim, B., et al. (författare) Temperature-dependent molecular conduction measured by the electrochemical deposition of a platinum electrode in a lateral configuration 2004 Ingår i: APPLIED PHYSICS LETTERS. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 85:20, s. 4756-4758 Tidskriftsartikel (refereegranskat)
39.	Kim, Do-Kyung, et al. (författare) Polymeric nanocomposites of complex ferrite 2004 Ingår i: Functional Nanomaterials For Optoelectronics And Other Applications. ; , s. 165-168 Konferensbidrag (refereegranskat)abstract The influence of mixtures of Ni0.5Zn0.4CU0.1Fe2O4, CoFe2O4, and graphite on the permeability, permittivity and microwave absorption properties in a composite embedded with insulating polymeric matrix, that can be used for X- and P-band radar absorption, has been investigated. Thermodynamic modelling of the complex ferrite system has been demonstrated by the controlled simultaneous coprecipitation of all ions inolved in the composite in the selected working pH ranges. The method employed is very convenient for the synthesis of multicomponent systems with a homogenous distribution of compositions.
40.	Koo, S. M., et al. (författare) Combination of JFET and MOSFET devices in 4H-SiC for high-temperature stable circuit operation 2003 Ingår i: Electronics Letters. - : Institution of Engineering and Technology (IET). - 0013-5194 .- 1350-911X. ; 39:12, s. 933-935 Tidskriftsartikel (refereegranskat)abstract A novel combination of junction-gated and metal-oxide-semiconductor field effect transistor (JMOSFET) has been fabricated and characterised in 4H-SiC. The high-temperature stable operation of JMOSFETs has been explored in terms of constant current levels. The JMOSFETs have shown the feasibility for operating with constant on and off current levels from room temperature up to 300degreesC. Another advantage of this device is the improved current density by accumulation of the MOS n-channel.
41.	Lee, SangWook, et al. (författare) Production of individual suspended single-walled carbon nanotubes using the ac electrophoresis technique 2004 Ingår i: Applied Physics A-Materials Science & Processing. - : Springer Science and Business Media LLC. - 0947-8396. ; 78:3, s. 283-286 Tidskriftsartikel (refereegranskat)
42.	Lee, Y, et al. (författare) The nuclear RNase III Drosha initiates microRNA processing 2003 Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 425:6956, s. 415-419 Tidskriftsartikel (refereegranskat)
43.	Lu, KM, et al. (författare) Two genes that map to the STSL locus cause sitosterolemia: genomic structure and spectrum of mutations involving sterolin-1 and sterolin-2, encoded by ABCG5 and ABCG8, respectively 2001 Ingår i: American journal of human genetics. - : Elsevier BV. - 0002-9297. ; 69:2, s. 278-290 Tidskriftsartikel (refereegranskat)
44.	Moon, S.J., Fournier, K.B., Scott, H., Chung, H-K, Lee, R.W. (författare) Optical pumping experiments in the XUV regime. 2003 Ingår i: J. Quant. Spectroscopy & Radiative Transfer. ; 81, s. 311-17. Tidskriftsartikel (refereegranskat)
45.	Yu, C. H., et al. (författare) Superdeformed and Highly Deformed Bands in 65Zn and Neutron-proton Interactions in Zn Isotopes 2000 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 62:4 Tidskriftsartikel (refereegranskat)abstract Superdeformed and highly deformed rotational bands were established in Zn-65 using the Ca-40(Si-29,4p)Zn-65 reaction, and averaged quadrupole moments were measured for two of these bands. The configurations of these bands were assigned based on Hartree-Fock calculations. One of the three bands exhibits at low (h) over bar omega a rise in the J((2)) dynamic moments of inertia that is similar to the alignment gain observed in Zn-60. A comparison of the rotational band configurations and their J((2)) moments of inertia for light Zn isotopes suggests that the rise in J((2)) is most likely caused by np interactions associated with the valence protons and neutrons occupying the g(9/2) intruder orbits.
46.	Danielsson, Erik, et al. (författare) Dry etching and metallization schemes in a GaN/SiC heterojunction device process 2000 Ingår i: Materials Science Forum. - : Trans Tech Publications Inc.. - 0255-5476 .- 1662-9752. ; 338-342, s. 1049-1052 Tidskriftsartikel (refereegranskat)abstract Dry etching and metallization schemes are described for a GaN/SiC heterojunction. GaN was reactive ion etched in a chlorine based chemistry (Cl2/Ar), and an ICP etch was used on 4H-SiC using a fluorine based chemistry (SF6/Ar/O2). The etch rates obtained on GaN was above 400 nm/min. High sample temperature from self heating and large dc-bias was the probable cause for the high etch rate. The ICP etch rate on SiC approached 320 nm/min, and the etch selectivity to GaN was >100. The metallization was based on Ti for both n-GaN and p-SiC. TLM and Kelvin structures were used to extract the specific contact resistivity, ÏC. After a 950 Â°C anneal in N2 ÏC on the GaN samples were below 1Â·10-6 Î©cm2 for sputtered contacts in room temperature, and an order of magnitude higher with evaporation. On p-SiC no ohmic behavior was found with a doping of 4Â·1018 cm-3, but the same contact metallization on highly doped areas (>1020 cm-3) showed ohmic behavior with ÏC below 10-4 Î©cm2.
47.	Franzke, CW, et al. (författare) Transmembrane collagen XVII, an epithelial adhesion protein, is shed from the cell surface by ADAMs 2002 Ingår i: The EMBO journal. - : Wiley. - 0261-4189 .- 1460-2075. ; 21:19, s. 5026-5035 Tidskriftsartikel (refereegranskat)
48.	Johnson, S.L., Heimann, P.A., Lindenberg, A.M., Jeschke, H.O., Garcia, M.E., Chang, Z., Lee, R.W., Rehr, J.J., Falcone, R.W. (författare) Properties of liquid silicon observed by time-resolved X-ray absorption spectroscopy 2003 Ingår i: Physical Review Letters. ; 91, s. 157403/1-4. Tidskriftsartikel (refereegranskat)
49.	Kluzniak, W., et al. (författare) Nonlinear Resonance in the Accretion Disk of a Millisecond Pulsar 2004 Ingår i: The Astrophysical Journal Letters. ; 603 Tidskriftsartikel (refereegranskat)
50.	Lee, SF, et al. (författare) A conserved GXXXG motif in APH-1 is critical for assembly and activity of the gamma-secretase complex 2004 Ingår i: The Journal of biological chemistry. - 0021-9258. ; 279:6, s. 4144-4152 Tidskriftsartikel (refereegranskat)

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