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161.
Elizabeth Ann Maharaj Pierpaolo D’Urso Don U. A. Galagedera 《Journal of Classification》2010,27(2):231-275
Traditional procedures for clustering time series are based mostly on crisp hierarchical or partitioning methods. Given that
the dynamics of a time series may change over time, a time series might display patterns that may enable it to belong to one
cluster over one period while over another period, its pattern may be more consistent with those in another cluster. The traditional
clustering procedures are unable to identify the changing patterns over time. However, clustering based on fuzzy logic will
be able to detect the switching patterns from one time period to another thus enabling some time series to simultaneously
belong to more than one cluster. In particular, this paper proposes a fuzzy approach to the clustering of time series based
on their variances through wavelet decomposition. We will show that this approach will distinguish between time series with
different patterns in variability as well identifying time series with switching patterns in variability. 相似文献
162.
朱安女 《大理学院学报:综合版》2010,9(9)
爨氏是古代白族的大姓之一,东晋时期的<爨宝子碑>、刘宋时期的<爨龙颜碑>作为白族先民的碑刻文献,是魏晋南北朝时期白族文学的重要文本."二爨碑"的产生分别前于<文心雕龙>九十余年和四十余年,其体式与刘勰<文心雕龙>阐释的诔碑理论范式几乎偶合,为刘勰诔碑理论提供珍贵的历史文献实证,在白族古代文学发展史上具有上承后汉滇文化,下启唐代南诏文化的重要意义. 相似文献
163.
164.
Carolyn Ann Cobbold 《Annals of science》2018,75(1):21-39
This article reveals how nineteenth-century chemists and health reformers tried to eradicate the use of yeast in bread, claiming they had devised healthier and more sanitary ways to raise bread. It describes the alternative technological solutions to baking bread, investigating factors that influenced their development and adaptation in the marketplace. A lack of scientific and cultural consensus surrounding yeast, what it was and what it did, fermented during this period. The conflict over yeast helped create a heterogeneous industrialization of the baking industry, changing processes and ingredients and creating new forms of bakery products. By examining the claims of promoters of rival scientific beliefs and technologies, as well as those of users and social commentators, we can see that technology’s eventual adaptation and impact on society is not predictable at its outset. Exploring the relationship between differing scientific beliefs, cultural understandings and alternative technologies also shows how science and industry cannot be isolated from their social and cultural context. The examination of the nineteenth-century technological development of commonplace commodities such as bread, baking powder and yeast, also reveals and explores a story that has not been told before in the history of science and technology. Why it has not been told is as enlightening as the story itself, revealing as it does our own privileging of what is important in science and history. 相似文献
165.
Simms RJ Hynes AM Eley L Inglis D Chaudhry B Dawe HR Sayer JA 《Cellular and molecular life sciences : CMLS》2012,69(6):993-1009
Joubert syndrome and related diseases (JSRD) are cerebello-oculo-renal syndromes with phenotypes including cerebellar hypoplasia,
retinal dystrophy, and nephronophthisis (a cystic kidney disease). Mutations in AHI1 are the most common genetic cause of JSRD, with developmental hindbrain anomalies and retinal degeneration being prominent
features. We demonstrate that Ahi1, a WD40 domain-containing protein, is highly conserved throughout evolution and its expression
associates with ciliated organisms. In zebrafish ahi1 morphants, the phenotypic spectrum of JSRD is modeled, with embryos showing brain, eye, and ear abnormalities, together with
renal cysts and cloacal dilatation. Following ahi1 knockdown in zebrafish, we demonstrate loss of cilia at Kupffer’s vesicle and subsequently defects in cardiac left–right
asymmetry. Finally, using siRNA in renal epithelial cells we demonstrate a role for Ahi1 in both ciliogenesis and cell–cell
junction formation. These data support a role for Ahi1 in epithelial cell organization and ciliary formation and explain the
ciliopathy phenotype of AHI1 mutations in man. 相似文献
166.
Sung WK Zheng H Li S Chen R Liu X Li Y Lee NP Lee WH Ariyaratne PN Tennakoon C Mulawadi FH Wong KF Liu AM Poon RT Fan ST Chan KL Gong Z Hu Y Lin Z Wang G Zhang Q Barber TD Chou WC Aggarwal A Hao K Zhou W Zhang C Hardwick J Buser C Xu J Kan Z Dai H Mao M Reinhard C Wang J Luk JM 《Nature genetics》2012,44(7):765-769
To survey hepatitis B virus (HBV) integration in liver cancer genomes, we conducted massively parallel sequencing of 81 HBV-positive and 7 HBV-negative hepatocellular carcinomas (HCCs) and adjacent normal tissues. We found that HBV integration is observed more frequently in the tumors (86.4%) than in adjacent liver tissues (30.7%). Copy-number variations (CNVs) were significantly increased at HBV breakpoint locations where chromosomal instability was likely induced. Approximately 40% of HBV breakpoints within the HBV genome were located within a 1,800-bp region where the viral enhancer, X gene and core gene are located. We also identified recurrent HBV integration events (in ≥ 4 HCCs) that were validated by RNA sequencing (RNA-seq) and Sanger sequencing at the known and putative cancer-related TERT, MLL4 and CCNE1 genes, which showed upregulated gene expression in tumor versus normal tissue. We also report evidence that suggests that the number of HBV integrations is associated with patient survival. 相似文献
167.
Evans DM Spencer CC Pointon JJ Su Z Harvey D Kochan G Oppermann U Opperman U Dilthey A Pirinen M Stone MA Appleton L Moutsianas L Moutsianis L Leslie S Wordsworth T Kenna TJ Karaderi T Thomas GP Ward MM Weisman MH Farrar C Bradbury LA Danoy P Inman RD Maksymowych W Gladman D Rahman P;Spondyloarthritis Research Consortium of Canada 《Nature genetics》2011,43(8):761-767
Ankylosing spondylitis is a common form of inflammatory arthritis predominantly affecting the spine and pelvis that occurs in approximately 5 out of 1,000 adults of European descent. Here we report the identification of three variants in the RUNX3, LTBR-TNFRSF1A and IL12B regions convincingly associated with ankylosing spondylitis (P < 5 × 10(-8) in the combined discovery and replication datasets) and a further four loci at PTGER4, TBKBP1, ANTXR2 and CARD9 that show strong association across all our datasets (P < 5 × 10(-6) overall, with support in each of the three datasets studied). We also show that polymorphisms of ERAP1, which encodes an endoplasmic reticulum aminopeptidase involved in peptide trimming before HLA class I presentation, only affect ankylosing spondylitis risk in HLA-B27-positive individuals. These findings provide strong evidence that HLA-B27 operates in ankylosing spondylitis through a mechanism involving aberrant processing of antigenic peptides. 相似文献
168.
Haiman CA Chen GK Blot WJ Strom SS Berndt SI Kittles RA Rybicki BA Isaacs WB Ingles SA Stanford JL Diver WR Witte JS Hsing AW Nemesure B Rebbeck TR Cooney KA Xu J Kibel AS Hu JJ John EM Gueye SM Watya S Signorello LB Hayes RB Wang Z Yeboah E Tettey Y Cai Q Kolb S Ostrander EA Zeigler-Johnson C Yamamura Y Neslund-Dudas C Haslag-Minoff J Wu W Thomas V Allen GO Murphy A Chang BL Zheng SL Leske MC Wu SY Ray AM Hennis AJ Thun MJ Carpten J Casey G Carter EN Duarte ER Xia LY Sheng X Wan P Pooler LC 《Nature genetics》2011,43(6):570-573
In search of common risk alleles for prostate cancer that could contribute to high rates of the disease in men of African ancestry, we conducted a genome-wide association study, with 1,047,986 SNP markers examined in 3,425 African-Americans with prostate cancer (cases) and 3,290 African-American male controls. We followed up the most significant 17 new associations from stage 1 in 1,844 cases and 3,269 controls of African ancestry. We identified a new risk variant on chromosome 17q21 (rs7210100, odds ratio per allele = 1.51, P = 3.4 × 10(-13)). The frequency of the risk allele is ~5% in men of African descent, whereas it is rare in other populations (<1%). Further studies are needed to investigate the biological contribution of this allele to prostate cancer risk. These findings emphasize the importance of conducting genome-wide association studies in diverse populations. 相似文献
169.
This article presents data on trends in the percentage of maternities taking place at home in the UK. As well as the national trend, the article examines how home maternity levels vary according to mother's age, number of previous live births within marriage, country of birth, region, local authority and NHS Trust. Examination of trends and variations in home maternity levels provides a context for debates regarding factors that may influence where women give birth. 相似文献
170.
Loss-of-function mutations in the gene encoding filaggrin cause ichthyosis vulgaris 总被引:21,自引:0,他引:21
Smith FJ Irvine AD Terron-Kwiatkowski A Sandilands A Campbell LE Zhao Y Liao H Evans AT Goudie DR Lewis-Jones S Arseculeratne G Munro CS Sergeant A O'Regan G Bale SJ Compton JG DiGiovanna JJ Presland RB Fleckman P McLean WH 《Nature genetics》2006,38(3):337-342
Ichthyosis vulgaris (OMIM 146700) is the most common inherited disorder of keratinization and one of the most frequent single-gene disorders in humans. The most widely cited incidence figure is 1 in 250 based on a survey of 6,051 healthy English schoolchildren. We have identified homozygous or compound heterozygous mutations R501X and 2282del4 in the gene encoding filaggrin (FLG) as the cause of moderate or severe ichthyosis vulgaris in 15 kindreds. In addition, these mutations are semidominant; heterozygotes show a very mild phenotype with incomplete penetrance. The mutations show a combined allele frequency of approximately 4% in populations of European ancestry, explaining the high incidence of ichthyosis vulgaris. Profilaggrin is the major protein of keratohyalin granules in the epidermis. During terminal differentiation, it is cleaved into multiple filaggrin peptides that aggregate keratin filaments. The resultant matrix is cross-linked to form a major component of the cornified cell envelope. We find that loss or reduction of this major structural protein leads to varying degrees of impaired keratinization. 相似文献