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1.
Dunham A Matthews LH Burton J Ashurst JL Howe KL Ashcroft KJ Beare DM Burford DC Hunt SE Griffiths-Jones S Jones MC Keenan SJ Oliver K Scott CE Ainscough R Almeida JP Ambrose KD Andrews DT Ashwell RI Babbage AK Bagguley CL Bailey J Bannerjee R Barlow KF Bates K Beasley H Bird CP Bray-Allen S Brown AJ Brown JY Burrill W Carder C Carter NP Chapman JC Clamp ME Clark SY Clarke G Clee CM Clegg SC Cobley V Collins JE Corby N Coville GJ Deloukas P Dhami P Dunham I Dunn M Earthrowl ME Ellington AG 《Nature》2004,428(6982):522-528
Chromosome 13 is the largest acrocentric human chromosome. It carries genes involved in cancer including the breast cancer type 2 (BRCA2) and retinoblastoma (RB1) genes, is frequently rearranged in B-cell chronic lymphocytic leukaemia, and contains the DAOA locus associated with bipolar disorder and schizophrenia. We describe completion and analysis of 95.5 megabases (Mb) of sequence from chromosome 13, which contains 633 genes and 296 pseudogenes. We estimate that more than 95.4% of the protein-coding genes of this chromosome have been identified, on the basis of comparison with other vertebrate genome sequences. Additionally, 105 putative non-coding RNA genes were found. Chromosome 13 has one of the lowest gene densities (6.5 genes per Mb) among human chromosomes, and contains a central region of 38 Mb where the gene density drops to only 3.1 genes per Mb. 相似文献
2.
Deloukas P Earthrowl ME Grafham DV Rubenfield M French L Steward CA Sims SK Jones MC Searle S Scott C Howe K Hunt SE Andrews TD Gilbert JG Swarbreck D Ashurst JL Taylor A Battles J Bird CP Ainscough R Almeida JP Ashwell RI Ambrose KD Babbage AK Bagguley CL Bailey J Banerjee R Bates K Beasley H Bray-Allen S Brown AJ Brown JY Burford DC Burrill W Burton J Cahill P Camire D Carter NP Chapman JC Clark SY Clarke G Clee CM Clegg S Corby N Coulson A Dhami P Dutta I Dunn M Faulkner L Frankish A 《Nature》2004,429(6990):375-381
3.
Cumulant functions are introduced to describe the statistical state of a radiation field. These functions are simply related
to the optical coherence functions but have some interesting features. It is shown that if the cumulant functions of all orders
greater than some numberN
0 vanish then they also vanish for all orders greater than 2. Thermal field is the only field having this property. This property
holds whether the field is described by a classical stochastic process or by a quantum density operator. Further the particular
operator ordering used in defining these cumulant functions for the quantized field affects only the second order cumulant
function. To describe the statistical state of a vector field such as partially polarized or unpolarized radiation, one would
need to introduce cumulant tensors. 相似文献
4.
MA Freitas CL Hendrickson AG Marshall 《Rapid communications in mass spectrometry : RCM》1999,13(15):1639-1642
We present a novel approach for the determination of activation energy for the unimolecular dissociation of a large (>50 atoms) ion, based on measurement of the unimolecular dissociation rate constant as a function of continuous-wave CO(2) laser intensity. Following a short ( approximately 1 s) induction period, CO(2) laser irradiation produces an essentially blackbody internal energy distribution, whose 'temperature' varies inversely with laser intensity. The only currently available method for measuring such activation energies is blackbody infrared radiative dissociation (BIRD). Compared with BIRD, FRAGMENT: (a) eliminates the need to heat the surrounding ion trap and vacuum chamber to each of several temperatures (each requiring hours for temperature equilibration); (b) offers a three-fold wider range of effective blackbody temperature; and (c) extends the range of applications to include initially cold ions (e.g., gas-phase H/D exchange). Our FRAGMENT-determined activation energy for dissociation of protonated bradykinin, 1.2 +/- 0.1 eV, agrees within experimental error to the value, 1.3 +/- 0.1 eV, previously reported by Williams et al. from BIRD experiments. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
5.
The DNA sequence of human chromosome 22 总被引:75,自引:0,他引:75
Dunham I Shimizu N Roe BA Chissoe S Hunt AR Collins JE Bruskiewich R Beare DM Clamp M Smink LJ Ainscough R Almeida JP Babbage A Bagguley C Bailey J Barlow K Bates KN Beasley O Bird CP Blakey S Bridgeman AM Buck D Burgess J Burrill WD O'Brien KP 《Nature》1999,402(6761):489-495
Knowledge of the complete genomic DNA sequence of an organism allows a systematic approach to defining its genetic components. The genomic sequence provides access to the complete structures of all genes, including those without known function, their control elements, and, by inference, the proteins they encode, as well as all other biologically important sequences. Furthermore, the sequence is a rich and permanent source of information for the design of further biological studies of the organism and for the study of evolution through cross-species sequence comparison. The power of this approach has been amply demonstrated by the determination of the sequences of a number of microbial and model organisms. The next step is to obtain the complete sequence of the entire human genome. Here we report the sequence of the euchromatic part of human chromosome 22. The sequence obtained consists of 12 contiguous segments spanning 33.4 megabases, contains at least 545 genes and 134 pseudogenes, and provides the first view of the complex chromosomal landscapes that will be found in the rest of the genome. 相似文献
6.
D.M.S. Bagguley J.P. Partington J.A. Robertson R.C. Woods 《Journal of magnetism and magnetic materials》1980,20(1):56-66
Measurements of magnetization, ac susceptibility and microwave absorption at 9.5 and 35 GHz, have been carried out with single crystals of Tb and Gd70Tb30. The critical temperatures for Tb were in agreement with previous published results. The Curie Temperature for Gd70Tb30 was measured to be (275 ± 2) K. Anisotropy constants have been derived from the microwave measurements. The value of K2 at 0 K is estimated to 8.8 × 108 erg cm-3 (Tb) and 1.3 × 108 erg cm-3 (Gd70Tb30). At 77 K, the value of K6 is estimated to be 6 × 104 erg cm-3 (Gd70Tb30. 相似文献
7.
Mungall AJ Palmer SA Sims SK Edwards CA Ashurst JL Wilming L Jones MC Horton R Hunt SE Scott CE Gilbert JG Clamp ME Bethel G Milne S Ainscough R Almeida JP Ambrose KD Andrews TD Ashwell RI Babbage AK Bagguley CL Bailey J Banerjee R Barker DJ Barlow KF Bates K Beare DM Beasley H Beasley O Bird CP Blakey S Bray-Allen S Brook J Brown AJ Brown JY Burford DC Burrill W Burton J Carder C Carter NP Chapman JC Clark SY Clark G Clee CM Clegg S Cobley V Collier RE Collins JE Colman LK Corby NR Coville GJ 《Nature》2003,425(6960):805-811
8.
Gregory SG Barlow KF McLay KE Kaul R Swarbreck D Dunham A Scott CE Howe KL Woodfine K Spencer CC Jones MC Gillson C Searle S Zhou Y Kokocinski F McDonald L Evans R Phillips K Atkinson A Cooper R Jones C Hall RE Andrews TD Lloyd C Ainscough R Almeida JP Ambrose KD Anderson F Andrew RW Ashwell RI Aubin K Babbage AK Bagguley CL Bailey J Beasley H Bethel G Bird CP Bray-Allen S Brown JY Brown AJ Buckley D Burton J Bye J Carder C Chapman JC Clark SY Clarke G Clee C Cobley V Collier RE Corby N 《Nature》2006,441(7091):315-321
The reference sequence for each human chromosome provides the framework for understanding genome function, variation and evolution. Here we report the finished sequence and biological annotation of human chromosome 1. Chromosome 1 is gene-dense, with 3,141 genes and 991 pseudogenes, and many coding sequences overlap. Rearrangements and mutations of chromosome 1 are prevalent in cancer and many other diseases. Patterns of sequence variation reveal signals of recent selection in specific genes that may contribute to human fitness, and also in regions where no function is evident. Fine-scale recombination occurs in hotspots of varying intensity along the sequence, and is enriched near genes. These and other studies of human biology and disease encoded within chromosome 1 are made possible with the highly accurate annotated sequence, as part of the completed set of chromosome sequences that comprise the reference human genome. 相似文献
9.
D.M.S. Bagguley J.P. Partington J.A. Robertson R.C. Woods 《Journal of magnetism and magnetic materials》1981,22(3):291-305
Measurements of magnetization, ac susceptibility and microwave absorption at 9.5 and 35 GHz, have been carried out with single crystals of Dy, Tb74Y26, Tb79Y21, Tb81Y19. These crystals exhibit a stable helix phase at high temperatures; Tb74Y26, Tb79Y21, also exhibit a low temperature ‘frozen-in’ antiferromagnet state. The critical temperatures Tc, TN, and the maximum critical field for the stable helix-ferromagnet transition are, Dy: 80 K, 179 K, 11 kG; Tb74Y26: 25 K, 198 K, 9.6 kG; Tb79Y21: 93 K, 202 K, 7.4 kG; Tb81Y19: 116 K, 205 K, 5.5 kG. Values for the exchange parameter {() - (0)} estimated from the data are about 0.2 x 10-3 eV. 相似文献
10.
铌酸锶钡薄膜的微结构与电光性能的研究 总被引:3,自引:1,他引:2
本文叙述了使用溶胶凝胶法在MgO(0 0 1)的衬底上制备铌酸锶钡薄膜的过程 ,膜层厚度可达 5 μm。通过X射线衍射、摇摆曲线、扫描、拉曼散射光谱等方法研究了薄膜的微结构性能 ,实验发现 ,铌酸锶钡薄膜具有了较好的 (0 0 1)方向的优先取向性能 ,并且随着薄膜厚度的增加 ,其晶体取向性也会随之不断改进。熔石英的透明衬底上生长的SBN薄膜具有较大的电致双折射效应 ,其有效电光系数能够高达 6 6 2× 10 -11m/V。 相似文献