| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Ablikim, M., et al.
(författare)
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Measurements of (XcJ)-> K+K-K+K- decays
- 2006
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 642:3, s. 197-202
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Tidskriftsartikel (refereegranskat)abstract
- Using 14M psi(2S) events taken with the BESII detector, chi(cJ) -> 2(K+K-) decays are studied. For the four-kaon final state, the branching fractions are B(chi(c0,1,2) ->.2(K+K-)) = (3.48 +/- 0.23 +/- 0.47) x 10(-3), (0.70 +/- 0.13 +/- 0.10) x 10(-3), and (2.17 +/- 0.20 +/- 0.31) x 10(-3). For the phi K+K- final state, the branching fractions, which are measured for the first time, are B(chi(c0,1,2) -> phi K+K-) = (1.03 +/- 0.22 +/- 0.15) x 10(-3), (0.46 +/- 0.16 +/- 0.06) x 10(-3), and (1.67 +/- 0.26 +/- 0.24) x 10(-4). For the phi phi final state, B(chi(c0,2) -> phi phi) = (0.94 +/- 0.21 +/- 0.13) x 10(-3) and (1.70 +/- 0.30 +/- 0.25) x 10(-3).
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| 3. |
- Carninci, P, et al.
(författare)
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The transcriptional landscape of the mammalian genome
- 2005
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Ingår i: Science (New York, N.Y.). - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 309:5740, s. 1559-1563
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Tidskriftsartikel (refereegranskat)abstract
- This study describes comprehensive polling of transcription start and termination sites and analysis of previously unidentified full-length complementary DNAs derived from the mouse genome. We identify the 5′ and 3′ boundaries of 181,047 transcripts with extensive variation in transcripts arising from alternative promoter usage, splicing, and polyadenylation. There are 16,247 new mouse protein-coding transcripts, including 5154 encoding previously unidentified proteins. Genomic mapping of the transcriptome reveals transcriptional forests, with overlapping transcription on both strands, separated by deserts in which few transcripts are observed. The data provide a comprehensive platform for the comparative analysis of mammalian transcriptional regulation in differentiation and development.
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| 4. |
- Iacopetta, B, et al.
(författare)
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Functional categories of TP53 mutation in colorectal cancer: results of an International Collaborative Study.
- 2006
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Ingår i: Annals of oncology : official journal of the European Society for Medical Oncology / ESMO. - : Elsevier BV. - 0923-7534. ; 17:5, s. 842-7
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Loss of TP53 function through gene mutation is a critical event in the development and progression of many tumour types including colorectal cancer (CRC). In vitro studies have found considerable heterogeneity amongst different TP53 mutants in terms of their transactivating abilities. The aim of this work was to evaluate whether TP53 mutations classified as functionally inactive (< or=20% of wildtype transactivation ability) had different prognostic and predictive values in CRC compared with mutations that retained significant activity. MATERIALS AND METHODS: TP53 mutations within a large, international database of CRC (n = 3583) were classified according to functional status for transactivation. RESULTS: Inactive TP53 mutations were found in 29% of all CRCs and were more frequent in rectal (32%) than proximal colon (22%) tumours (P < 0.001). Higher frequencies of inactive TP53 mutations were also seen in advanced stage tumours (P = 0.0003) and in tumours with the poor prognostic features of vascular (P = 0.006) and lymphatic invasion (P = 0.002). Inactive TP53 mutations were associated with significantly worse outcome only in patients with Dukes' stage D tumours (RR = 1.71, 95%CI 1.25-2.33, P < 0.001). Patients with Dukes' C stage tumours appeared to gain a survival benefit from 5-fluorouracil-based chemotherapy regardless of TP53 functional status for transactivation ability. CONCLUSIONS: Mutations that inactivate the transactivational ability of TP53 are more frequent in advanced CRC and are associated with worse prognosis in this stage of disease.
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| 5. |
- Luyssaert, S., et al.
(författare)
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CO2 balance of boreal, temperate, and tropical forests derived from a global database
- 2007
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 13:12, s. 2509-2537
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Forskningsöversikt (refereegranskat)abstract
- Terrestrial ecosystems sequester 2.1 Pg of atmospheric carbon annually. A large amount of the terrestrial sink is realized by forests. However, considerable uncertainties remain regarding the fate of this carbon over both short and long timescales. Relevant data to address these uncertainties are being collected at many sites around the world, but syntheses of these data are still sparse. To facilitate future synthesis activities, we have assembled a comprehensive global database for forest ecosystems, which includes carbon budget variables (fluxes and stocks), ecosystem traits (e.g. leaf area index, age), as well as ancillary site information such as management regime, climate, and soil characteristics. This publicly available database can be used to quantify global, regional or biome-specific carbon budgets; to re-examine established relationships; to test emerging hypotheses about ecosystem functioning [e.g. a constant net ecosystem production (NEP) to gross primary production (GPP) ratio]; and as benchmarks for model evaluations. In this paper, we present the first analysis of this database. We discuss the climatic influences on GPP, net primary production (NPP) and NEP and present the CO2 balances for boreal, temperate, and tropical forest biomes based on micrometeorological, ecophysiological, and biometric flux and inventory estimates. Globally, GPP of forests benefited from higher temperatures and precipitation whereas NPP saturated above either a threshold of 1500 mm precipitation or a mean annual temperature of 10 degrees C. The global pattern in NEP was insensitive to climate and is hypothesized to be mainly determined by nonclimatic conditions such as successional stage, management, site history, and site disturbance. In all biomes, closing the CO2 balance required the introduction of substantial biome-specific closure terms. Nonclosure was taken as an indication that respiratory processes, advection, and non-CO2 carbon fluxes are not presently being adequately accounted for.
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| 6. |
- Ding, Li, et al.
(författare)
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Somatic mutations affect key pathways in lung adenocarcinoma
- 2008
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 455:7216, s. 1069-1075
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Tidskriftsartikel (refereegranskat)abstract
- Determining the genetic basis of cancer requires comprehensive analyses of large collections of histopathologically well-classified primary tumours. Here we report the results of a collaborative study to discover somatic mutations in 188 human lung adenocarcinomas. DNA sequencing of 623 genes with known or potential relationships to cancer revealed more than 1,000 somatic mutations across the samples. Our analysis identified 26 genes that are mutated at significantly high frequencies and thus are probably involved in carcinogenesis. The frequently mutated genes include tyrosine kinases, among them the EGFR homologue ERBB4; multiple ephrin receptor genes, notably EPHA3; vascular endothelial growth factor receptor KDR; and NTRK genes. These data provide evidence of somatic mutations in primary lung adenocarcinoma for several tumour suppressor genes involved in other cancers--including NF1, APC, RB1 and ATM--and for sequence changes in PTPRD as well as the frequently deleted gene LRP1B. The observed mutational profiles correlate with clinical features, smoking status and DNA repair defects. These results are reinforced by data integration including single nucleotide polymorphism array and gene expression array. Our findings shed further light on several important signalling pathways involved in lung adenocarcinoma, and suggest new molecular targets for treatment.
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| 7. |
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| 8. |
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| 9. |
- Yu, G., et al.
(författare)
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Structures, electronic states, photoluminescence, and carrier transport properties of 1,1-disubstituted 2,3,4,5-tetraphenylsiloles
- 2005
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 127:17, s. 6335-6346
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Forskningsöversikt (refereegranskat)abstract
- The excellent electroluminescent (EL) properties of 1,1-disubstituted 2,3,4,5-tetraphenylsiloles, 1-methyl-1,2,3,4,5-pentaphenylsilole (MPPS), and 1,1,2,3,4,5-hexaphenylsilole (HPS) have been found. Despite some studies devoted to these materials, very little is known about the real origin of their unique EL properties. Therefore, we investigated the structures, photoluminescence (PL), and charge carrier transport properties of 1,1-disubstituted 2,3,4,5-tetraphenylsiloles as well as the effect of substituents on these characteristics. The single crystals of the three siloles involving 1,1-dimethyl-2,3,4,5-tetraphenylsilole (DMTPS), MPPS, and HIPS were grown and their crystal structures were determined by X-ray diffraction. Three siloles have nonplanar molecular structures. The substituents at 1,1-positions enhance the steric hindrance and have predominant influence on the twisted degree of phenyl groups at ring carbons. This nonplanar structure reduces the intermolecular interaction and the likelihood of excimer formation, and increases PL efficiency in the solid state. The silole films show high fluorescence quantum yields (75-85%), whereas their dilute solutions exhibit a faint emission. The electronic structures of the three siloles were investigated using quantum chemical calculations. The highest occupied molecular orbitals (HOMOs) and the lowest unoccupied molecular orbitals (LUMOs) are mainly localized on the silole ring and two phenyl groups at 2,5-positions in all cases, while the LUMOs have a significant orbital density at two exocyclic Si-C bonds. The extremely theoretical studies of luminescent properties were carried out. We calculated the nonradiative decay rate of the first excited state as well as the radiative one. It is found that the faint emission of DMTPS in solutions mainly results from the huge nonradiative decay rate. In solid states, molecular packing can remarkably restrict the intramolecular rotation of the peripheral side phenyl ring, which has a large contribution to the nonradiative transition process. This explains why the 1,1-disubstituted 2,3,4,5-tetraphenylsiloles in the thin films exhibit high fluorescence quantum yields. The charge carrier mobilities of the MPPS and HPS films were measured using a transient EL technique. We obtained a mobility of 2.1 x 10(-6) cm(2)/V(.)s in the MPPS film at an electric field of 1.2 x 10(6) V/cm. This mobility is comparable to that of Alq(3), which is one of the most extensively used electron transport materials in organic light-emitting diodes (LEDs), at the same electric field. The electron mobility of the HPS film is about similar to 1.5 times higher than that of the MPPS film. To the best of our knowledge, this kind of material is one of the most excellent emissive materials that possess both high charge carrier mobility and high PL efficiency in the solid states simultaneously. The excellent EL performances of MPPS and HPS are presumably ascribed to these characteristics.
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| 10. |
- Antoniou, A C, et al.
(författare)
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Breast and ovarian cancer risks to carriers of the BRCA1 5382insC and 185delAG and BRCA2 6174delT mutations: a combined analysis of 22 population based studies
- 2005
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Ingår i: Journal of Medical Genetics. - : BMJ. - 0022-2593 .- 1468-6244. ; 42:7, s. 602-603
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Tidskriftsartikel (refereegranskat)abstract
- A recent report estimated the breast cancer risks in carriers of the three Ashkenazi founder mutations to be higher than previously published estimates derived from population based studies. In an attempt to confirm this, the breast and ovarian cancer risks associated with the three Ashkenazi founder mutations were estimated using families included in a previous meta-analysis of populatrion based studies. The estimated breast cancer risks for each of the founder BRCA1 and BRCA2 mutations were similar to the corresponding estimates based on all BRCA1 or BRCA2 mutations in the meta-analysis. These estimates appear to be consistent with the observed prevalence of the mutations in the Ashkenazi Jewish population.
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