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1.	Aabenhus, Rune, et al. (författare) First attempt to produce experimental Campylobacter concisus infection in mice 2008 Ingår i: World Journal of Gastroenterology. - : Baishideng Publishing Group Inc.. - 1007-9327. ; 14:45, s. 6954-6959 Tidskriftsartikel (refereegranskat)abstract AIM: To infect mice with atypical Campylobacter concisus (C concisus) for the first time. METHODS: Three separate experiments were conducted in order to screen the ability of five clinical C concisus isolates of intestinal origin and the ATCC 33237 type strain of oral origin to colonize and produce infection in immunocompetent BALB/cA mice. The majority of the BALB/cA mice were treated with cyclophosphamide prior to C concisus inoculation to suppress immune functions. Inoculation of C concisus was performed by the gastric route. RESULTS: C concisus was isolated from the liver, ileum and jejunum of cyclophosphamide-treated mice in the first experiment. No C concisus strains were isolated in the two subsequent experiments. Mice infected with C concisus showed a significant loss of body weight from day two through to day five of infection but this decreased at the end of the first week. Histopathologicalexamination did not consistently find signs of inflammation in the gut, but occasionally microabscesses were found in the liver of infected animals. CONCLUSION: Transient colonization with C concisus was observed in mice with loss of body weight. Future studies should concentrate on the first few days after inoculation and in other strains of mice. (C) 2008 The WJG Press. All rights reserved.
2.	Aaby, Peter, et al. (författare) Vaccinia scars associated with better survival for adults. An observational study from Guinea-Bissau 2006 Ingår i: Vaccine. - : Elsevier BV. - 1873-2518 .- 0264-410X. ; 24:29-30, s. 5718-5718 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: Live vaccines including BCG and measles may have non-targeted beneficial effects on childhood survival in areas with high mortality. The authors therefore undertook a survey of vaccinia scars to evaluate subsequent mortality. SUBJECTS: Based on a population census, a cohort of 1893 adults in urban Guinea-Bissau was examined in 1998 and followed until 2002. MAIN OUTCOME MEASURE: All cause mortality, excluding accidents. RESULTS: The median age of vaccinia vaccinations had been 16-18 years. Adults with a vaccinia scar had a mortality ratio (MR) of 0.60 (0.41-0.87) compared to those without any scar. The effect was stronger for women. Mortality decreased with each additional vaccinia scar (MR=0.73 (0.56-0.95)). Among 502 individuals with information on HIV infection, the age-adjusted HIV-2 prevalence was 2.45 (1.06-5.65) for those with a vaccinia scar. Control for district, ethnic group, schooling, place of birth, quality of housing and HIV status had little effect on the estimate. Since vaccinia and BCG scars could have been confused, mortality for adults with vaccinia and/or BCG scar was compared to those without, the MR being 0.61 (0.41-0.89). CONCLUSION: Known cultural or socio-economic factors possibly associated with access to vaccination had no influence on the mortality ratio for having a vaccinia scar. Hence, vaccinia vaccination may have a prolonged beneficial effect on adult survival.
3.	Aaltonen, Emil, et al. (författare) Transmembrane topology of the Acr3 family arsenite transporter from Bacillus subtilis. 2008 Ingår i: Biochimica et Biophysica Acta - Biomembranes. - : Elsevier BV. - 0005-2736. ; 1778:4, s. 963-973 Tidskriftsartikel (refereegranskat)abstract The transmembrane topology of the Acr3 family arsenite transporter Acr3 from Bacillus subtilis was analysed experimentally using translational fusions with alkaline phosphatase and green fluorescent protein and in silico by topology modelling. Initial topology prediction resulted in two models with 9 and 10 TM helices respectively. 32 fusion constructs were made between truncated forms of acr3 and the reporter genes at 17 different sites throughout the acr3 sequence to discriminate between these models. Nine strong reporter protein signals provided information about the majority of the locations of the cytoplasmic and extracellular loops of Acr3 and showed that both the N- and the C-termini are located in the cytoplasm. Two ambiguous data points indicated the possibility of an alternative 8 helix topology. This possibility was investigated using another 10 fusion variants, but no experimental support for the 8 TM topology was obtained. We therefore conclude that Acr3 has 10 transmembrane helices. Overall, the loops which connect the membrane spanning segments are short, with cytoplasmic loops being somewhat longer than the extracellular loops. The study provides the first ever experimentally derived structural information on a protein of the Acr3 family which constitutes one of the largest classes of arsenite transporters.
4.	Aaltonen, Kirsimari, et al. (författare) Cyclin D1 expression is associated with poor prognostic features in estrogen receptor positive breast cancer 2009 Ingår i: Breast Cancer Research and Treatment. - : Springer Science and Business Media LLC. - 1573-7217 .- 0167-6806. ; 113:1, s. 75-82 Tidskriftsartikel (refereegranskat)abstract Cyclins D1 and E play an important role in breast carcinogenesis. High cyclin E expression is common in hormone receptor negative and high grade aggressive breast cancer, whereas cyclin D1 in hormone receptor positive and low grade breast cancer. Experimental data has suggested that cyclin D1 and E mediate cell proliferation by different mechanisms in estrogen receptor (ER) positive and negative breast cancer. To test this hypotheses in large breast cancer material and to clarify the histopathological correlations of cyclin E and D1, especially the association with proliferation, we analyzed cyclin E and D1 immunohistochemical expression on breast tumour microarrays consisting of 1348 invasive breast cancers. High cyclin D1 expression was associated with high grade (P < 0.0005), high cyclin A (P < 0.0005) and Ki67 (P < 0.0005) expression among ER positive but with low grade (P = 0.05) and low Ki67 (P = 0.01) expression among ER negative breast cancers. Cyclin E and D1 expression correlated positively in ER positive (P < 0.0005) but had a negative correlation in ER negative tumours (P = 0.004). Cyclin E associated with high grade among all tumours (P < 0.0005). In conclusion, the findings of this study show that cyclin D1 has separate roles, and proliferation is driven by different mechanisms in ER positive and negative breast cancers.
5.	Aaltonen, Kristina, et al. (författare) Molecular Population Genetics of the SRK and SCR Self-incompatibility Genes in the Wild Plant Species Brassica cretica (Brassicaceae). 2009 Ingår i: Genetics. - : Oxford University Press (OUP). - 0016-6731 .- 1943-2631. ; 181:3, s. 985-995 Tidskriftsartikel (refereegranskat)abstract Self-incompatibility (SI) in plants is a classic example of a trait evolving under strong frequency-dependent selection. As a consequence, population genetic theory predicts that the S locus, which controls SI, should maintain numerous alleles, display a high level of nucleotide diversity, and, in structured populations, show a lower level of among-population differentiation compared to neutral loci. Population-level investigations of DNA sequence variation at the S locus have recently been carried out in the genus Arabidopsis, largely confirming results from theoretical models of S-locus evolutionary dynamics, but no comparable studies have been done in wild Brassica species. In this study, we sequenced parts of the S-locus genes SRK and SCR, two tightly linked genes that are directly involved in the determination of SI specificity, in samples from four natural populations of the wild species Brassica cretica. The amount and distribution of nucleotide diversity, as well as the frequency spectrum of putative functional haplotypes, observed at the S locus in B. cretica fit very well with expectations from theoretical models, providing strong evidence for frequency-dependent selection acting on the S locus in a wild Brassica species.
6.	Aaltonen, Kristina, et al. (författare) Nuclear and chloroplast microsatellites reveal extreme population differentiation and limited gene flow in the Aegean endemic Brassica cretica (Brassicaceae) 2007 Ingår i: Molecular Ecology. - 0962-1083. ; 16:23, s. 4972-4983 Tidskriftsartikel (refereegranskat)abstract Nuclear and chloroplast microsatellite markers were used to study population structure and gene flow among seven Cretan populations of the Aegean endemic plant species Brassica cretica (Brassicaceae). Both nuclear and chloroplast markers revealed exceptionally high levels of population differentiation (overall FST = 0.628 and 1.000, respectively) and relatively little within-population diversity (overall HS = 0.211 and 0.000, respectively). Maximum-likelihood estimates of directional migration rates were low among all pairs of populations (average Nm = 0.286). There was no evidence that differences in flower colour between populations had any influence on historical levels of gene flow. In addition, a haplotype network showed that all five chloroplast haplotypes found in the sample were closely related. Together, these results suggest that current patterns of diversification in B. cretica are mainly a result of genetic drift during the last half million years. The main conclusions from the present study are consistent with the prevailing hypothesis that plant diversification in the Aegean region is driven by random rather than adaptive differentiation among isolated populations.
7.	Aaltonen, Kristina, et al. (författare) The Evolution and Diversification of S-locus Haplotypes in the Brassicaceae Family. 2009 Ingår i: Genetics. - : Oxford University Press (OUP). - 0016-6731 .- 1943-2631. ; 181:3, s. 977-984 Tidskriftsartikel (refereegranskat)abstract Self-incompatibility (SI) in the Brassicaceae plant family is controlled by the SRK and SCR genes situated at the S locus. A large number of S haplotypes have been identified, mainly in cultivated species of the Brassica and Raphanus genera, but recently also in wild Arabidopsis species. Here, we used DNA sequences from the SRK and SCR genes of the wild Brassica species B. cretica, together with publicly available sequence data from other Brassicaceae species, to investigate the evolutionary relationships between S haplotypes in the Brassicaceae family. The results reveal that wild and cultivated Brassica species have similar levels of SRK diversity indicating that domestication has had but a minor effect on S-locus diversity in Brassica. Our results also show that a common set of S haplotypes were present in the ancestor of the Brassica and Arabidopsis genera, that only a small number of haplotypes survived in the Brassica lineage after its separation from Arabidopsis, and that diversification within the two Brassica dominance classes occurred after the split between the two lineages. We also find indications that recombination may have occurred between the kinase domain of SRK and the SCR gene in Brassica.
8.	Aaltonen, Kristina, et al. (författare) Unequal segregation of SRK alleles at the S locus in Brassica cretica. 2008 Ingår i: Genetical Research. - 1469-5073. ; 90:3, s. 223-228 Tidskriftsartikel (refereegranskat)abstract In the Brassicaceae plant family, which includes the Arabidopsis and Brassica genera, self-incompatibility (SI) is controlled by genes at the S locus. Using experimental crosses, we studied the pattern of inheritance of S-locus alleles in the wild species Brassica cretica. Four full-sib families were established and unequal segregation of alleles at the SRK SI gene was found in one family. The segregation distortion acted in favour of a recessive (class II) allele and was best explained by some form of gametic-level selection. Our findings are discussed in the light of theoretical predictions of differential accumulation of deleterious mutations among S-locus alleles.
9.	Aanen, M C, et al. (författare) A detailed analysis of sodium removal by peritoneal dialysis: comparison with predictions from the three-pore model of membrane function 2005 Ingår i: Nephrology Dialysis Transplantation. - : Oxford University Press (OUP). - 1460-2385 .- 0931-0509. ; 20:6, s. 1192-1200 Tidskriftsartikel (refereegranskat)abstract Background. The development of fluid and salt retention is a potential problem for all peritoneal dialysis (PD) patients. Sodium removal by the peritoneum is predominantly determined by convective fluid loss but influenced by diffusion and sieving due to free water transport as predicted by the three-pore model (TPM). The aim of the study was to establish the effect of transport status, dwell length and glucose concentration on observed ultrafiltration (UF), dialysate sodium concentration ([Na+](D)) and removal, and compare this with that predicted by a computer program based on the principles of the TPM. Methods. This was a cross-sectional study of UF and [Na+](D) collected prospectively from dwells classified by length, glucose concentration and membrane transport characteristics. Solute transport, converted to area parameter and UF capacity, was measured on each occasion by the peritoneal equilibration test. These parameters, along with plasma [Na+], were entered into the computer model. Fixed values for other parameters, e.g. hydraulic conductance and lymphatic absorption and sump volume, were used. Results. A total of 1853 dwells from 182 patients [10% were on automated PD (APD)] were analysed. There was a high degree of correlation (r=0.83-95, P<0.001) between the observed and predicted values for UF, [Na+](D) and sodium removal across the full range of dwell categories. The model overpredicted UF as the net volume increased with increasing glucose concentration, independently of solute transport. This bias was not fully explained by the preferential use of hypertonic dialysate by patients with reduced UF capacity. The prediction of [Na+](D) described sodium sieving, which was overestimated in a small number of patients with UF failure. There were no discrepancies between continous ambulatory PD (CAPD) and APD patients. Conclusion. This analysis endorses the TPM as a description of membrane function, particularly in relation to sodium sieving and removal. The relationship between dialysate glucose concentration and achieved UF appears to be more complex; even accounting for extended time on treatment and reduction in the osmotic conductance in patients preferentially using hypertonic exchanges, further adjustments may be needed to account for the tendency to overestimate UF.
10.	Aapro, M, et al. (författare) Guidance on the use of bisphosphonates in solid tumours: recommendations of an international expert panel 2008 Ingår i: Annals of Oncology. - : Elsevier BV. - 1569-8041 .- 0923-7534. ; 19:3, s. 420-432 Tidskriftsartikel (refereegranskat)abstract Bisphosphonates (BP) prevent, reduce, and delay cancer-related skeletal complications in patients, and have substantially decreased the prevalence of such events since their introduction. Today, a broad range of BP with differences in potency, efficacy, dosing, and administration as well as approved indications is available. In addition, results of clinical trials investigating the efficacy of BP in cancer treatment-induced bone loss (CTIBL) have been recently published. The purpose of this paper is to review the current evidence on the use of BP in solid tumours and provide clinical recommendations. An interdisciplinary expert panel of clinical oncologists and of specialists in metabolic bone diseases assessed the widespread evidence and information on the efficacy of BP in the metastatic and nonmetastatic setting, as well as ongoing research on the adjuvant use of BP. Based on available evidence, the panel recommends amino-bisphosphonates for patients with metastatic bone disease from breast cancer and zoledronic acid for patients with other solid tumours as primary disease. Dosing of BP should follow approved indications with adjustments if necessary. While i.v. administration is most often preferable, oral administration (clodronate, IBA) may be considered for breast cancer patients who cannot or do not need to attend regular hospital care. Early-stage cancer patients at risk of developing CTIBL should be considered for preventative BP treatment. The strongest evidence in this setting is now available for ZOL. Overall, BP are well-tolerated, and most common adverse events are influenza-like syndrome, arthralgia, and when used orally, gastrointestinal symptoms. The dose of BP may need to be adapted to renal function and initial creatinine clearance calculation is mandatory according to the panel for use of any BP. Subsequent monitoring is recommended for ZOL and PAM, as described by the regulatory authority guidelines. Patients scheduled to receive BP (mainly every 3-4 weeks i.v.) should have a dental examination and be advised on appropriate measures for reducing the risk of jaw osteonecrosis. BP are well established as supportive therapy to reduce the frequency and severity of skeletal complications in patients with bone metastases from different cancers.
11.	Aarnio, Harri, et al. (författare) Recombination studies in a polyfluorene copolymer for photovoltaic applications 2005 Ingår i: Synthetic Metals. - : Elsevier BV. - 0379-6779. ; 155:2, s. 299-302 Tidskriftsartikel (refereegranskat)abstract We present detailed continuous wave (cw) and transient photoinduced absorption (PA) measurements in thin films of a novel alternating polyfluorene copolymer, poly[2,7-(9,9-dioctyl-fluorene)-alt-5,5-(4',7'-di-2-thienyl-2',1',3-benzo-thiadiazole)] (DiO-PFDTBT), and its blends with the sol. fullerene deriv. [6,6]-phenyl-C61-butyric acid Me ester (PCBM) in wt. ratios of 1:0, 4:1 and 1:4. We measure the frequency, intensity and temp. dependence of the PA signal in the frequency domain, and compare with the results obtained from the transient PA decay measurements in the time domain. In all blends, the PA spectrum shows a broad high energy PA band ranging from .apprx.1 eV to 2 eV as well as a low energy band peaking at .apprx.0.35 eV. We attribute the low energy band to the P1 transition of polarons and part of the high energy band to the correlated P2 transition of polarons. Both frequency and time domain measurements show that the high energy band has two decay components, a faster component in the microsecond time regime and a slower component in the millisecond time regime. The slow component is strongly dispersive, whereas the fast component is practically non-dispersive. [on SciFinder (R)]
12.	Aaron, F. D., et al. (författare) A general search for new phenomena at HERA 2009 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 674:4-5, s. 257-268 Tidskriftsartikel (refereegranskat)abstract A model-independent search for deviations from the Standard Model prediction is performed using the full e(+/-) p data sample collected by the H1 experiment at HERA. All event topologies involving isolated electrons, photons, muons, neutrinos and jets with transverse momenta above 20 GeV are investigated in a single analysis. Events are assigned to exclusive classes according to their final state. A dedicated algorithm is used to search for deviations from the Standard Model in the distributions of the scalar sum of transverse momenta or the invariant mass of final state particles and to quantify their significance. Variables related to angular distributions and energy sharing between final state particles are also introduced to study the final state topologies. No significant deviation from the Standard Model expectation is observed in the phase space covered by this analysis. (C) 2009 Elsevier B.V. All rights reserved.
13.	Aaron, F. D., et al. (författare) A precision measurement of the inclusive ep scattering cross section at HERA 2009 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 64:4, s. 561-587 Tidskriftsartikel (refereegranskat)abstract A measurement of the inclusive deep inelastic neutral current e(+) p scattering cross section is reported in the region of four-momentum transfer squared, 12GeV(2) <= Q(2) <= 150 GeV2, and Bjorken x, 2 x 10(-4) <= x <= 0.1. The results are based on data collected by the H1 Collaboration at the ep collider HERA at positron and proton beam energies of E-e = 27.6 GeV and E-p = 920 GeV, respectively. The data are combined with previously published data, taken at E-p = 820 GeV. The accuracy of the combined measurement is typically in the range of 1.3-2%. A QCD analysis at next-to-leading order is performed to determine the parton distributions in the proton based on H1 data.
14.	Aaron, F. D., et al. (författare) A search for excited neutrinos in e(-) p collisions at HERA 2008 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 663:5, s. 382-389 Tidskriftsartikel (refereegranskat)abstract A search for first generation excited neutrinos is performed using the full e(-) p data sample collected by the HI experiment at HERA at a centre-of-mass energy of 319 GeV, corresponding to a total luminosity of 184 pb(-1). The electroweak decays of excited neutrinos nu* -> nu gamma, v* -> nu Z and nu* -> eW with subsequent hadronic or leptonic decays of the W and Z bosons are considered. No evidence for excited neutrino production is found. Mass dependent exclusion limits on nu* production cross sections and on the ratio of the coupling to the compositeness scale f/boolean AND are derived within gauge mediated models. A limit on f/boolean AND A, independent of the relative couplings to the SU(2) and U(1) gauge bosons, is also determined. These limits extend the excluded region to higher masses than has been possible in previous excited neutrino searches. (c) 2008 Elsevier B.V. All rights reserved.
15.	Aaron, F.D., et al. (författare) Charged particle production in high Q^2 deep-inelastic scattering at HERA 2007 Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 654:5-6, s. 148-159 Tidskriftsartikel (refereegranskat)abstract The average charged track multiplicity and the normalised distribution of the scaled momentum, xp, of charged final state hadrons are measured in deep-inelastic ep scattering at high Q2 in the Breit frame of reference. The analysis covers the range of photon virtuality Click to view the MathML source. Compared with previous results presented by HERA experiments this analysis has a significantly higher statistical precision and extends the phase space to higher Q2 and to the full range of xp. The results are compared with e+e− annihilation data and with various calculations based on perturbative QCD using different models of the hadronisation process.
16.	Aaron, F. D., et al. (författare) Deeply virtual Compton scattering and its beam charge asymmetry in e(+/-)p collisions at HERA 2009 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 681:5, s. 391-399 Tidskriftsartikel (refereegranskat)abstract A measurement of elastic deeply virtual Compton scattering gammap --> gamma p using e(+) p and e(-) p collision data recorded with the HI detector at HERA is presented. The analysed data sample corresponds to an integrated luminosity of 306 pb(-1), almost equally shared between both beam charges. The cross section is measured as a function of the virtuality Q(2) of the exchanged photon and the centre-of-mass energy W of the gammap system in the kinematic domain 6.5 < Q(2) < 80 GeV2, 30 < W < 140 GeV and \|t\| < 1 GeV2, where t denotes the squared momentum transfer at the proton vertex. The cross section is determined differentially in t for different Q(2) and W values and exponential t-slope parameters are derived. Using e(+) p and e(-) p data samples, a beam charge asymmetry is extracted for the first time in the low Biorken x kinematic domain. The observed asymmetry is attributed to the interference between Bethe-Heitler and deeply virtual Compton scattering processes. Experimental results are discussed in the context of two different models, one based on generalised parton distributions and one based on the dipole approach. (C) 2009 Elsevier B.V. All rights reserved.
17.	Aaron, F. D., et al. (författare) Events with isolated leptons and missing transverse momentum and measurement of W production at HERA 2009 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 64:2, s. 251-271 Tidskriftsartikel (refereegranskat)abstract Events with high energy isolated electrons, muons or tau leptons and missing transverse momentum are studied using the full e(+/-)p data sample collected by the H1 experiment at HERA, corresponding to an integrated luminosity of 474 pb(-1). Within the Standard Model, events with isolated leptons and missing transverse momentum mainly originate from the production of single W bosons. The total single W boson production cross section is measured as 1.14 +/- 0.25 (stat.) +/- 0.14 (sys.) pb, in agreement with the Standard Model expectation. The data are also used to establish limits on the WW gamma gauge couplings and for a measurement of the W boson polarisation.
18.	Aaron, F. D., et al. (författare) Inclusive photoproduction of rho(0), K(0) and phi mesons at HERA H1 Collaboration 2009 Ingår i:* Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 673:2, s. 119-126 Tidskriftsartikel (refereegranskat)abstract Inclusive non-diffractive photoproduction of rho(770)(0), K*(892)(0) and phi(1020) mesons is investigated with the H1 detector in ep collisions at HERA. The corresponding average gamma p centre-of-mass energy is 210 GeV. The mesons are measured in the transverse momentum range 0.5 < p(T) < 7 GeV and the rapidity range vertical bar y(lab)vertical bar < 1. Differential cross sections are presented as a function of transverse momentum and rapidity, and are compared to the predictions of hadroproduction models. (C) 2009 Elsevier B.V. All rights reserved.
19.	Aaron, F. D., et al. (författare) Measurement of diffractive scattering of photons with large momentum transfer at HERA 2009 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 672:3, s. 219-226 Tidskriftsartikel (refereegranskat)abstract The first measurement of diffractive scattering of quasi-real photons with large momentum transfer gamma p -> gamma Y, where Y is the proton dissociative system, is made using the H1 detector at HERA. The measurement is performed for initial photon virtualities Q(2) < 0.01 GeV2. Single differential cross sections are Measured as a function of W, the incident photon-proton centre of mass energy, and t, the square of the four-momentum transferred at the proton vertex, in the range 175 < W < 247 GeV and 4 < \|t\| < 36 GeV2. The W dependence is well described by a model based on perturbative QCD using a leading logarithmic approximation of the BFKL evolution. The measured \|t\| dependence is harder than that predicted by the model and those observed in exclusive vector meson production. (C) 2009 Published by Elsevier B.V.
20.	Aaron, F. D., et al. (författare) Measurement of isolated photon production in deep-inelastic scattering at HERA 2008 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 54:3, s. 371-387 Tidskriftsartikel (refereegranskat)abstract The production of isolated photons in deep-inelastic scattering ep -> e gamma X is measured with the H1 detector at HERA. The measurement is performed in the kinematic range of negative four-momentum transfer squared 4 < Q(2)< 150 GeV2 and a mass of the hadronic system W-X > 50 GeV. The analysis is based on a total integrated luminosity of 227 pb(-1). The production cross section of isolated photons with a transverse energy in the range 3 < E-T(gamma)< 10 GeV and pseudorapidity range -1.2
21.	Aaron, F. D., et al. (författare) Measurement of the inclusive ep scattering cross section at low Q (2) and x at HERA 2009 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 63:4, s. 625-678 Tidskriftsartikel (refereegranskat)abstract A measurement of the inclusive ep scattering cross section is presented in the region of low momentum transfers, 0.2 GeV2 a parts per thousand currency signQ (2)a parts per thousand currency sign12 GeV2, and low Bjorken x, 5a <...10(-6)a parts per thousand currency signxa parts per thousand currency sign0.02. The result is based on two data sets collected in dedicated runs by the H1 Collaboration at HERA at beam energies of 27.6 GeV and 920 GeV for positrons and protons, respectively. A combination with data previously published by H1 leads to a cross section measurement of a few percent accuracy. A kinematic reconstruction method exploiting radiative ep events extends the measurement to lower Q (2) and larger x. The data are compared with theoretical models which apply to the transition region from photoproduction to deep inelastic scattering.
22.	Aaron, F. D., et al. (författare) Measurement of the proton structure function F-L(x, Q(2)) at low x 2008 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 665:4, s. 139-146 Tidskriftsartikel (refereegranskat)abstract A first measurement is reported of the longitudinal proton structure function FL(X, Q(2)) at the ep collider HERA. It is based on inclusive deep inelastic e(+)p scattering cross section measurements with a positron beam energy of 27.5 GeV and proton beam energies of 920, 575 and 460 GeV. Employing the energy dependence of the cross section, FL is measured in a range of squared four-momentum transfers 12 <= Q2 <=, 90 GeV2 and low Bjorken x 0.00024 <= x <= 0.0036. The F-L values agree with higher order QCD calculations based on parton densities obtained using cross section data previously measured at HERA. (C) 2008 Elsevier B.V. All rights reserved.
23.	Aaron, F. D., et al. (författare) Multi-lepton production at high transverse momenta in ep collisions at HERA 2008 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 668:4, s. 268-276 Tidskriftsartikel (refereegranskat)abstract Processes leading to a final state with at least two high transverse momentum leptons (electrons or muons) are studied using the full e(+/-) p data sample collected by the H1 experiment at HERA. The data correspond to an integrated luminosity of 463 pb(-1). Di-lepton and tri-lepton event classes are investigated. Cross sections of the production of e(+)e(-) and mu(+)mu(-) pairs are derived in a restricted phase space dominated by photon-photon collisions. In general, good agreement is found with Standard Model predictions. Events are observed with a total scalar sum of lepton transverse momenta above 100 GeV where the Standard Model expectation is low. In this region, combining di-lepton and tri-lepton classes, five events are observed in e(+) p collisions, compared to a Standard Model expectation of 0.96 +/- 0.12, while no such event is observed in e(-) p data for 0.64 +/- 0.09 expected. (C) 2008 Elsevier B.V. All rights reserved.
24.	Aaron, F. D., et al. (författare) Multi-leptons with high transverse momentum at HERA 2009 Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479. ; :10 Tidskriftsartikel (refereegranskat)abstract Events with at least two high transverse momentum leptons (electrons or muons) are studied using the H1 and ZEUS detectors at HERA with an integrated luminosity of 0.94 fb(-1). The observed numbers of events are in general agreement with the Standard Model predictions. Seven di- and tri-lepton events are observed in e(+)p collision data with a scalar sum of the lepton transverse momenta above 100 GeV while 1.94 +/- 0.17 events are expected. Such events are not observed in e(-)p collisions for which 1.19 +/- 0.12 are predicted. Total visible and differential di-electron and di-muon photoproduction cross sections are extracted in a restricted phase space dominated by photon-photon collisions.
25.	Aaron, F. D., et al. (författare) Observation of the hadronic final state charge asymmetry in high Q(2) deep-inelastic scattering at HERA 2009 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 681:2, s. 125-133 Tidskriftsartikel (refereegranskat)abstract A first measurement is presented of the charge asymmetry in the hadronic final state from the hard interaction in deep-inelastic ep neutral current scattering at HERA. The measurement is performed in the range of negative squared four momentum transfer 100 < Q(2) < 8000 GeV2. The difference between the event normalised distributions of the scaled momentum, x(p), for positively and negatively charged particles, measured in the current region of the Breit frame, is studied together with its evolution as a function of Q. The results are compared to Monte Carlo models at the hadron and parton levels. (C) 2009 Elsevier B.V. All rights reserved.
26.	Aaron, F. D., et al. (författare) Search for excited electrons in ep collisions at HERA 2008 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 666:2, s. 131-139 Tidskriftsartikel (refereegranskat)abstract A search for excited electrons is performed using the full e(+/-) p data sample collected by the HI experiment at HERA, corresponding to a total luminosity of 475 pb(-1). The electroweak decays of excited electrons e* -> e gamma, e* -> eZ and e* -> vW with subsequent hadronic or leptonic decays of the W and Z bosons are considered. No evidence for excited electron production is found. Mass dependent exclusion limits on e* production cross sections and on the ratio f/Lambda of the coupling to the compositeness scale are derived within gauge mediated models. These limits extend the excluded region compared to previous excited electron searches. The e* production via contact interactions is also addressed for the first time in ep collisions. (C) 2008 Elsevier B.V. All rights reserved.
27.	Aaron, F. D., et al. (författare) Search for excited quarks in ep collisions at HERA 2009 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 678:4, s. 335-343 Tidskriftsartikel (refereegranskat)abstract A search for excited quarks is performed using the full e(+/-)p data sample collected by the HI experiment at HERA, corresponding to a total integrated luminosity of 475 pb(-1). The electroweak decays of excited quarks q* -> q gamma. q* -> qZ and q* - qW with Subsequent hadronic or leptonic decays of the W and Z bosons are considered. No evidence for first generation excited quark production is found. Mass dependent exclusion limits on q* production cross sections and on the ratio f/Lambda of the coupling to the compositeness scale are derived Within gauge mediated models. These limits extend the excluded region compared to previous excited quark searches. (C) 2009 Elsevier B.V. All rights reserved.
28.	Aaron, F. D., et al. (författare) Search for single top quark production at HERA 2009 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 678:5, s. 450-458 Tidskriftsartikel (refereegranskat)abstract A search for single top quark production is performed in the full e(+/-)p data sample collected by the H1 experiment at HERA, corresponding to an integrated luminosity of 474 pb(-1). Decays of top quarks into a b quark and a W boson with Subsequent leptonic or hadronic decay of the W are investigated. A multivariate analysis is performed to discriminate top quark production from Standard Model background processes. An upper limit on the top quark production cross section via flavour changing neutral current processes sigma(ep -> et X) < 0.25 pb is established at 95% CL. Limits on the anomalous coupling K-tu gamma are derived. (C) 2009 Elsevier B.V. All rights reserved.
29.	Aaron, F. D., et al. (författare) Strangeness production at low Q(2) in deep-inelastic ep scattering at HERA 2009 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 61:2, s. 185-205 Tidskriftsartikel (refereegranskat)abstract The production of neutral strange hadrons is investigated using deep-inelastic scattering events measured with the H1 detector at HERA. The measurements are made in the phase space defined by the negative four-momentum transfer squared of the photon 2 < Q(2) < 100 GeV2 and the inelasticity 0.1 < y < 0.6. The K-s(0) s and Lambda((Lambda) over bar) production cross sections and their ratios are determined. K-s(0) s production is compared to the production of charged particles in the same region of phase space. The Lambda-(Lambda) over bar asymmetry is also measured and found to be consistent with zero. Predictions of leading order Monte Carlo programs are compared to the data.
30.	Aaron, F. D., et al. (författare) Study of charm fragmentation into D (* +/-) mesons in deep-inelastic scattering at HERA 2009 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 59:3, s. 589-606 Tidskriftsartikel (refereegranskat)abstract The process of charm quark fragmentation is studied using D (* +/-) meson production in deep-inelastic scattering as measured by the H1 detector at HERA. The parameters of fragmentation functions are extracted for QCD models based on leading order matrix elements and DGLAP or CCFM evolution of partons together with string fragmentation and particle decays. Additionally, they are determined for a next-to-leading order QCD calculation in the fixed flavour number scheme using the independent fragmentation of charm quarks to D (* +/-) mesons. Two different regions of phase space are investigated defined by the presence or absence of a jet containing the D (* +/-) meson in the event. The fragmentation parameters extracted for the two phase space regions are found to be different.
31.	Aaron, F. D., et al. (författare) Three- and four-jet production at low x at HERA 2008 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 54:3, s. 389-409 Tidskriftsartikel (refereegranskat)abstract Three- and four-jet production is measured in deep-inelastic ep scattering at low x and Q(2) with the H1 detector using an integrated luminosity of 44.2 pb(-1). Several phase space regions are selected for the three-jet analysis in order to study the underlying parton dynamics from global topologies to the more restrictive regions of forward jets close to the proton direction. The measurements of cross sections for events with at least three jets are compared to fixed order QCD predictions of O(alpha(2)(s)) and O(alpha(3)(s)) and with Monte Carlo simulation programs where higher order effects are approximated by parton showers. A good overall description is provided by the O(alpha(3)(s)) calculation. Too few events are predicted at the lowest x similar to 10(-4), especially for topologies with two forward jets. This hints to large contributions at low x from initial state radiation of gluons close to the proton direction and unordered in transverse momentum. The Monte Carlo program in which gluon radiation is generated by the colour dipole model gives a good description of both the three- and the four-jet data in absolute normalisation and shape.
32.	Aarsland, D, et al. (författare) Memantine in patients with Parkinson's disease dementia or dementia with Lewy bodies: a double-blind, placebo-controlled, multicentre trial 2009 Ingår i: Lancet Neurology. - 1474-4465. ; 8:7, s. 613-618 Tidskriftsartikel (refereegranskat)
33.	Aarup, Lasse Rye, et al. (författare) The effect of different lung densities on the accuracy of various radiotherapy dose calculation methods: Implications for tumour coverage 2009 Ingår i: Radiotherapy and Oncology. - : Elsevier BV. - 1879-0887 .- 0167-8140. ; 91:3, s. 405-414 Tidskriftsartikel (refereegranskat)abstract Purpose: To evaluate against Monte-Carlo the performance of various dose calculations algorithms regarding lung turnout coverage in stereotactic body radiotherapy (SBRT) conditions. Materials and methods: Dose distributions in virtual lung phantoms have been calculated using four commercial Treatment Planning System (TPS) algorithms and one Monte Carlo (MC) system (EGSnrc). We compared the performance of the algorithms in calculating the target dose for different degrees of lung inflation. The phantoms had a cubic 'body' and 'lung' and a central 2-cm diameter spherical 'tumour' (the body and turnout have unit density). The lung tissue was assigned five densities (rho(lung)): 0.01, 0.1, 0.2, 0.4 and 1 g/cm(3). Four-field treatment plans were calculated with 6- and 18 MV narrow beams for each value of rho(lung). We considered the Pencil Beam Convolution (PBCEl) and the Analytical Anisotropic Algorithm (AAA(ECl)) from Varian Eclipse and the Pencil Beam Convolution (PBCOMP) and the Collapsed Cone Convolution (CCCOMP) algorithms from Oncentra MasterPlan. Results: When changing rho(lung) from 0.4 to 0.1 g/cm(3), the MC median target dose decreased from 89.2% to 74.9% for 6 MV and from 83.3% to 61.6% for 18 MV (of dose maximum in the homogenous case at both energies), while for both PB algorithms the median target dose was virtually independent of lung density. Conclusions: Both PB algorithms overestimated the target dose, the overestimation increasing as rho(lung) decreased. Concerning target dose, the AAA(ECl) and CCCOMP algorithms appear to be adequate alternatives to MC. (C) 2009 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and oncology 91 (2009) 405-414
34.	Abaraviciene, S, et al. (författare) Rosiglitazone counteracts palmitate-induced beta-cell dysfunction by suppression of MAP kinase, inducible nitric oxide synthase and caspase 3 activities. 2008 Ingår i: Cellular and Molecular Life Sciences. - : Springer Science and Business Media LLC. - 1420-9071 .- 1420-682X. ; 65:14, s. 2256-2265 Tidskriftsartikel (refereegranskat)abstract Chronic exposure of pancreatic islets to elevated levels of palmitate leads to beta-cell dysfunction. We examined possible involvement of mitogenactivated protein kinases (MAPKs) and caspase-3 in palmitate-induced beta-cell dysfunction and tested the influence of the anti-diabetic drug rosiglitazone (ROZ). Palmitate amplified glucose-stimulated augmentation of intracellular free calcium ([Ca(2+)](i)) and insulin secretion in incubated islets. ROZ suppressed this amplification, whereas it modestly augmented glucose-induced increase in these events. ROZ suppressed short-term palmitate-induced phosphorylation of pro-apoptotic MAPKs, i.e., SAPK/JNK and p38. Long-term islet culturing with palmitate induced inducible nitric oxide synthase (iNOS) and activated SAPK/JNK-p38. ROZ counteracted these effects. Both palmitate and cytokines activated caspase-3 in MIN6c4-cells and isolated islets. ROZ suppressed palmitate- but not cytokine-induced caspase-3 activation. Finally, after palmitate culturing, ROZ reversed the inhibitory effect on glucose-stimulated insulin release. We suggest that ROZ counteracts palmitateinduced deleterious effects on beta-cell function via suppression of iNOS, pro-apoptotic MAPKs and caspase-3 activities, as evidenced by restoration of glucose-stimulated insulin release.
35.	Abaravicius, Juozas, et al. (författare) Load Management from an Environmental Perspective 2006 Ingår i: Energy & Environment. - : SAGE Publications. - 0958-305X .- 2048-4070. ; 17:4, s. 583-601 Tidskriftsartikel (refereegranskat)abstract The key objective of this study is to discuss the possible environmental benefits of load management and evaluate their significance, primarily focusing on CO2 emissions reduction. The analysis is carried out on two levels: National – the Swedish electricity market, and local – one electric utility in southern Sweden. The results show the importance of considering the influence of site-specific or level-specific conditions on the environmental effects of load management. On the national level, load management measures can hardly provide significant environmental benefits in Sweden, due to the high hydropower production, which is the demand following production source. Emission reductions will rather be the result of energy efficiency measures, which will lower the load demand as well as the energy demand. However, when it comes to a local (utility) level, where load management is considered as an alternative to an installation of a peak diesel power plant, the benefits are clear.
36.	Abat, E., et al. (författare) Study of the response of the ATLAS central calorimeter to pions of energies from 3 to 9 GeV 2009 Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002 .- 1872-9576. ; 607:2, s. 372-386 Tidskriftsartikel (refereegranskat)abstract A fully instrumented slice of the ATLAS central detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. in this paper, the response of the central calorimeters to pions with energies in the range between 3 and 9 GeV is presented. The linearity and the resolution of the combined calorimetry (electromagnetic and hadronic calorimeters) was measured and compared to the prediction of a detector simulation program using the toolkit Geant 4. (C) 2009 Elsevier B.V. All rights reserved.
37.	Abat, E., et al. (författare) The ATLAS Transition Radiation Tracker (TRT) proportional drift tube: design and performance 2008 Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:2 Tidskriftsartikel (refereegranskat)abstract A straw proportional counter is the basic element of the ATLAS Transition Radiation Tracker (TRT). Its detailed properties as well as the main properties of a few TRT operating gas mixtures are described. Particular attention is paid to straw tube performance in high radiation conditions and to its operational stability.
38.	Abat, E., et al. (författare) The ATLAS TRT barrel detector 2008 Ingår i: Journal of Instrumentation. - 1748-0221. ; 3 Tidskriftsartikel (refereegranskat)abstract The ATLAS TRT barrel is a tracking drift chamber using 52,544 individual tubular drift tubes. It is one part of the ATLAS Inner Detector, which consists of three sub-systems: the pixel detector spanning the radius range 4 to 20 cm, the semiconductor tracker (SCT) from 30 to 52 cm, and the transition radiation tracker ( TRT) from 56 to 108 cm. The TRT barrel covers the central pseudo-rapidity region \|eta\| < 1, while the TRT endcaps cover the forward and backward eta regions. These TRT systems provide a combination of continuous tracking with many measurements in individual drift tubes ( or straws) and of electron identification based on transition radiation from fibers or foils interleaved between the straws themselves. This paper describes the recently-completed construction of the TRT Barrel detector, including the quality control procedures used in the fabrication of the detector.
39.	Abat, E., et al. (författare) The ATLAS TRT electronics 2008 Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:6 Tidskriftsartikel (refereegranskat)abstract The ATLAS inner detector consists of three sub-systems: the pixel detector spanning the radius range 4cm-20cm, the semiconductor tracker at radii from 30 to 52 cm, and the transition radiation tracker (TRT), tracking from 56 to 107 cm. The TRT provides a combination of continuous tracking with many projective measurements based on individual drift tubes (or straws) and of electron identification based on transition radiation from fibres or foils interleaved between the straws themselves. This paper describes the on and off detector electronics for the TRT as well as the TRT portion of the data acquisition (DAQ) system.
40.	Abat, E., et al. (författare) The ATLAS TRT end-cap detectors 2008 Ingår i: Journal of Instrumentation. - 1748-0221. ; 3 Tidskriftsartikel (refereegranskat)abstract The ATLAS TRT end-cap is a tracking drift chamber using 245,760 individual tubular drift tubes. It is a part of the TRT tracker which consist of the barrel and two end-caps. The TRT end-caps cover the forward and backward pseudo-rapidity region 1.0 < vertical bar eta vertical bar < 2.0, while the TRT barrel central eta region vertical bar eta vertical bar < 1.0. The TRT system provides a combination of continuous tracking with many measurements in individual drift tubes ( or straws) and of electron identification based on transition radiation from fibers or foils interleaved between the straws themselves. Along with other two sub-systems, namely the Pixel detector and Semi Conductor Tracker (SCT), the TRT constitutes the ATLAS Inner Detector. This paper describes the recently completed and installed TRT end-cap detectors, their design, assembly, integration and the acceptance tests applied during the construction.
41.	Abate, E., et al. (författare) Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors 2008 Ingår i: Journal of Instrumentation. - 1748-0221. ; 3 Tidskriftsartikel (refereegranskat)abstract The ATLAS (A Toroidal LHC ApparatuS) Inner Detector provides charged particle tracking in the centre of the ATLAS experiment at the Large Hadron Collider (LHC). The Inner Detector consists of three subdetectors: the Pixel Detector, the Semiconductor Tracker (SCT), and the Transition Radiation Tracker (TRT). This paper summarizes the tests that were carried out at the final stage of SCT+TRT integration prior to their installation in ATLAS. The combined operation and performance of the SCT and TRT barrel and endcap detectors was investigated through a series of noise tests, and by recording the tracks of cosmic rays. This was a crucial test of hardware and software of the combined tracker detector systems. The results of noise and cross-talk tests on the SCT and TRT in their final assembled configuration, using final readout and supply hardware and software, are reported. The reconstruction and analysis of the recorded cosmic tracks allowed testing of the offline analysis chain and verification of basic tracker performance parameters, such as efficiency and spatial resolution, in combined operation before installation.
42.	Abayneh, Sisay A, et al. (författare) Sensitivity of HIV-1 primary isolates to human anti-CD40 antibody-mediated suppression is related to co-receptor use 2008 Ingår i: AIDS Research and Human Retroviruses. - : Mary Ann Liebert Inc. - 1931-8405 .- 0889-2229. ; 24:3, s. 447-452 Tidskriftsartikel (refereegranskat)abstract The effect of CD40 ligation on infection by HIV-1 primary isolates with different R5 phenotypes was evaluated with a novel set of anti-CD40 monoclonal antibodies originating from a human phage display library. Five human monoclonal anti-CD40 antibodies of IgG1 subtype characterized by the ability to activate B cells via CD40 were tested for induction of the CC-chemokines RANTES and MIP-1alpha and inhibition of HIV-1 replication in primary monocyte-derived macrophages (MDM). All activating anti-CD40 antibodies were able to induce CC-chemokines in MDM. We chose the most potent antibody, clone B44, for further experiments. This antibody had a suppressive effect on HIV-1 isolates of the R5 phenotype with limited use of CCR5/CXCR4 chimeric receptors. In comparison, HIV-1 isolates with broader use of CCR5/CXCR4 chimeric receptors or with CXCR4 use were less sensitive to anti-CD40-induced suppression. The results indicate that HIV-1 replication is inhibited by human anti-CD40 monoclonal antibodies through the mechanism of CC-chemokine induction. This effect is thus restricted to HIV-1 isolates sensitive to inhibition by CC-chemokines.
43.	Abbas, Mazhar, et al. (författare) Biosorption of chromium (III) and chromium (VI) by untreated and pretreated Cassia fistula biomass from aqueous solutions 2008 Ingår i: Water, Air and Soil Pollution. - : Springer Science and Business Media LLC. - 1573-2932 .- 0049-6979. ; 191:1-4, s. 139-148 Tidskriftsartikel (refereegranskat)abstract The present study explained the effect of pretreatments on the biosorption of Cr (III) and Cr (VI) by Cassia fistula biomass from aqueous solutions. For this purpose Cassia fistula biomass was pretreated physically by heating, autoclaving, boiling and chemically with sodium hydroxide, formaldehyde, gluteraldehyde, acetic acid, hydrogen peroxide, commercial laundry detergent, orthophosphoric, sulphuric acid, nitric acid, and hydrochloric acid. The adsorption capacity of biomass for Cr (III) and Cr (VI) was found to be significantly improved by the treatments of gluteraldehyde (95.41 and 96.21 mg/g) and benzene (85.71 and 90.81 mg/g) respectively. The adsorption capacity was found to depend on pH, initial metal concentration, dose, size, kinetics, and temperature. Maximum adsorption of both the Cr (III) and Cr (VI) was observed at pH 5 and 2. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The kinetic studies showed that the sorption rates could be described better by a second order expression than by a more commonly applied Lagergren equation.
44.	Abbott, Jessica, et al. (författare) Correlated morphological and colour differences among females of the damselfly Ischnura elegans 2009 Ingår i: Ecological Entomology. - : Wiley. - 1365-2311 .- 0307-6946. ; 34:3, s. 378-386 Tidskriftsartikel (refereegranskat)abstract 1. The female-limited colour polymorphic damselfly Ischnura elegans has proven to be an interesting study organism both as an example of female sexual polymorphism, and in the context of the evolution of colour polymorphism, as a model of speciation processes. 2. Previous research suggests the existence of correlations between colour morph and other phenotypic traits, and the different female morphs in I. elegans may be pursuing alternative phenotypically integrated strategies. However, previous research on morphological differences in southern Swedish individuals of this species was only carried out on laboratory-raised offspring from a single population, leaving open the question of how widespread such differences are. 3. The present study therefore analysed multi-generational data from 12 populations, investigating morphological differences between the female morphs in the field, differences in the pattern of phenotypic integration between morphs, and quantified selection on morphological traits. 4. It was found that consistent morphological differences indeed existed between the morphs across populations, confirming that the previously observed differences were not simply a laboratory artefact. It was also found, somewhat surprisingly, that despite the existence of sexual dimorphism in body size and shape, patterns of phenotypic integration differed most between the morphs and not between the sexes. Finally, linear selection gradients showed that female morphology affected fecundity differently between the morphs. 5. We discuss the relevance of these results to the male mimicry hypothesis and to the existence of potential ecological differences between the morphs.
45.	Abbott, J. K., et al. (författare) Patterns of differentiation in a colour polymorphism and in neutral markers reveal rapid genetic changes in natural damselfly populations 2008 Ingår i: Molecular Ecology. - : Wiley-Blackwell. - 0962-1083 .- 1365-294X. ; 17:6, s. 1597-1604 Tidskriftsartikel (refereegranskat)abstract The existence and mode of selection operating on heritable adaptive traits can be inferred by comparing population differentiation in neutral genetic variation between populations (often using F-ST values) with the corresponding estimates for adaptive traits. Such comparisons indicate if selection acts in a diversifying way between populations, in which case differentiation in selected traits is expected to exceed differentiation in neutral markers [F-ST (selected) > F-ST (neutralfl, or if negative frequency-dependent selection maintains genetic polymorphisms and pulls populations towards a common stable equilibrium [FST (selected) < F-ST (neutral)]. Here, we compared F-ST values for putatively neutral data (obtained using amplified fragment length polymorphism) with estimates of differentiation in morph frequencies in the colour-polymorphic damselfly Ischnura elegans. We found that in the first year (2000), population differentiation in morph frequencies was significantly greater than differentiation in neutral loci, while in 2002 (only 2 years and 2 generations later), population differentiation in morph frequencies had decreased to a level significantly lower than differentiation in neutral loci. Genetic drift as an explanation for population differentiation in morph frequencies could thus be rejected in both years. These results indicate that the type and/or strength of selection on morph frequencies in this system can change substantially between years. We suggest that an approach to a common equilibrium morph frequency across all populations, driven by negative frequency-dependent selection, is the cause of these temporal changes. We conclude that inferences about selection obtained by comparing F-ST values from neutral and adaptive genetic variation are most useful when spatial and temporal data are available from several populations and time points and when such information is combined with other ecological sources of data.
46.	Abbott, Jessica, et al. (författare) Ontogeny of sexual dimorphism and phenotypic integration in heritable morphs 2008 Ingår i: Evolutionary Ecology. - : Springer Science and Business Media LLC. - 1573-8477 .- 0269-7653. ; 22:1, s. 103-121 Tidskriftsartikel (refereegranskat)abstract In this study we investigated the developmental basis of adult phenotypes in a non-model organism, a polymorphic damselfly (Ischnura elegans) with three female colour morphs. This polymorphic species presents an ideal opportunity to study intraspecific variation in growth trajectories, morphological variation in size and shape during the course of ontogeny, and to relate these juvenile differences to the phenotypic differences of the discrete adult phenotypes; the two sexes and the three female morphs. We raised larvae of different families in individual enclosures in the laboratory, and traced morphological changes during the course of ontogeny. We used principal components analysis to examine the effects of Sex, Maternal morph, and Own morph on body size and body shape. We also investigated the larval fitness consequences of variation in size and shape by relating these factors to emergence success. Females grew faster than males and were larger as adults, and there was sexual dimorphism in body shape in both larval and adult stages. There were also significant effects of both maternal morph and own morph on growth rate and body shape in the larval stage. There were significant differences in body shape, but not body size, between the adult female morphs, indicating phenotypic integration between colour, melanin patterning, and body shape. Individuals that emerged successfully grew faster and had different body shape in the larval stage, indicating internal (non-ecological) selection on larval morphology. Overall, morphological differences between individuals at the larval stage carried over to the adult stage. Thus, selection in the larval stage can potentially result in correlated responses in adult phenotypes and vice versa.
47.	Abbott, Jessica, et al. (författare) Phenotypic and genetic variation in emergence and development time of a trimorphic damselfly 2005 Ingår i: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 18:6, s. 1464-1470 Tidskriftsartikel (refereegranskat)abstract Although colour polymorphisms in adult organisms of many taxa are often adaptive in the context of sexual selection or predation, genetic correlations between colour and other phenotypic traits expressed early in ontogeny could also play an important role in polymorphic systems. We studied phenotypic and genetic variation in development time among female colour morphs in the polymorphic damselfly Ischnura elegans in the field and by raising larvae in a common laboratory environment. In the field, the three different female morphs emerged at different times. Among laboratory-raised families, we found evidence of a significant correlation between maternal morph and larval development time in both sexes. This suggests that the phenotypic correlation between morph and emergence time in the field has a parallel in a genetic correlation between maternal colour and offspring development time. Maternal colour morph frequencies could thus potentially change as correlated responses to selection on larval emergence dates. The similar genetic correlation in male offspring suggests that sex-limitation in this system is incomplete, which may lead to an ontogenetic sexual conflict between selection for early male emergence (protandry) and emergence times associated with maternal morph.
48.	Abbott, Karen C., et al. (författare) Environmental variation in ecological communities and inferences from single-species data 2009 Ingår i: Ecology. - 0012-9658. ; 90:5, s. 1268-1278 Tidskriftsartikel (refereegranskat)abstract Data are often collected for a single species within an ecological community, so quantitative tools for drawing inferences about the unobserved portions of the community from single-species data are valuable. In this paper, we present and examine a method for estimating community dimension (the number of strongly interacting species or groups) from time series data on a single species. The dynamics of one species can be strongly affected by environmental stochasticity acting not only on itself, but also on other species with which it interacts. By fully accounting for the effects of stochasticity on populations embedded in a community, our approach gives better estimates of community dimension than commonly used methods. Using a combination of time series data and simulations, we show that failing to properly account for stochasticity when attempting to relate population dynamics to attributes of the community can give misleading information about community dimension.
49.	Abd, Hadi, et al. (författare) Ante mortem diagnosis of amoebic encephalitis in a haematopoietic stem cell transplanted patient 2009 Ingår i: Scandinavian Journal of Infectious Diseases. - : Informa UK Limited. - 1651-1980 .- 0036-5548. ; 41:8, s. 619-622 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Acanthamoeba species are widely distributed free-living amoebae showing an increased role as human pathogens causing encephalitis, keratitis, pneumonitis and dermatitis. A haematopoietic stem cell transplanted (HSCT) patient developed purulent meningitis while awaiting regrafting. The meningitis was thought to be an endogenous infection arising from the mucous membranes primarily involving the cervicofacial regions, probably due to haematogenous spread facilitated by surgery. We diagnosed a fatal case of granulomatous amoebic encephalitis caused by Acanthamoeba castellanii by direct microscopy of a cerebrospinal fluid sample (CSF), Acanthamoeba cultivation, Giemsa staining, polymerase chain reaction and sequencing.
50.	Abdallah, J., et al. (författare) A determination of the centre-of-mass energy at LEP2 using radiative two-fermion events 2006 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 46:2, s. 295-305 Tidskriftsartikel (refereegranskat)abstract Using e(+)e(-) -> mu(+)mu(-)(gamma) and e(+)e(-) -> q (q) over bar(gamma) events radiative to the Z pole, DELPHI has determined the centre-of-mass energy, root s, using energy and momentum constraint methods. The results are expressed as deviations from the nominal LEP centre-of-mass energy, measured using other techniques. The results are found to be compatible with the LEP Energy Working Group estimates for a combination of the 1997 to 2000 data sets.

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