813 research outputs found

    A resource interaction perspective on standards competition: some evidence from the optical recording media industry

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    Technological changes and business network dynamics : a longitudinal perspective from the optical recording media industry

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    In the past thirty years, the IMP Group's Interaction and Network Approach has gained its increasing popularity in researching economic behaviours among resource-dependent business actors through relational linkages (Håkansson et al., 2004; Turnbull et al., 1996). Within network research, understanding the dynamics in business networks, in which interfirm relationships are regarded as crucial constituents, has been of particular interest (Johnston et al., 2006; Möller and Halinen, 1999). Moreover, technology has been identified as an important component driving the evolution of a business network, where technological change may bring about positive and negative effects on the relationships embedded in this network, and consequently, results in network dynamics (Afuah, 2000; Christensen, 1997; Håkansson and Waluszewski, 2002b; Lundgren, 1995). A perspective of resource interaction (e.g. Håkansson et al., 2009) suggests that technological change needs to be treated as a process rather than a critical event. However the nature of this process as well as how it impacts on the configuration of a technology-based business net and on dynamics of relationships constituting this net remains under-examined.Based on qualitative research methods, a longitudinal single-case study is chosen to conduct an empirical investigation in the optical recording media industry, in order to address the above research problems. To facilitate the data collection, a focal net perspective and an input-process-output model are employed. The focal net under study is characterised as a value-creating and technology-bundled business net. A total of 72 interviews were carried out in three stages and with the focal actor, its customers, suppliers and a complementor. The empirical data allows the research to reconstruct the evolution of the focal business net, which covers a time-span of more than 10 years from 1998 to 2008, and in which major technological change has taken place three times, from CD-R to DVD-/+R, DVD Double Layer and HD/Blu-ray technologies. In the development of the optical recording technology, the focal net has experienced four net reconfigurations in which radical changes of relationships as well as disturbance in resource interaction are observed. Based on the case study result, empirical observations are offered and new insights into the process of the arrival of technological change and net reconfiguration and relationship dynamics affected by this technological arrival are developed. Moreover, theoretical contribution, managerial implications, limitations and future research directions are provided.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Retraction: Estimation of progression of multi-state chronic disease using the Markov model and prevalence pool concept

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    This article [1] has been retracted because the Editors are unable to ensure the scientific veracity of the findings or the ethical conduct of the authors despite an extensive investigation

    Assessment of gene-covariate interactions by incorporating covariates into association mapping

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    The HLA region is considered to be the main genetic risk factor for rheumatoid arthritis. Previous research demonstrated that HLA-DRB1 alleles encoding the shared epitope are specific for disease that is characterized by antibodies to cyclic citrullinated peptides (anti-CCP). In the present study, we incorporated the shared epitope and either anti-CCP antibodies or rheumatoid factor into linkage disequilibrium mapping, to assess the association between the shared epitope or antibodies with the disease gene identified. Incorporating the covariates into the association mapping provides a mechanism 1) to evaluate gene-gene and gene-environment interactions and 2) to dissect the pathways underlying disease induction/progress in quantitative antibodies

    A new analysis tool for individual-level allele frequency for genomic studies

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    <p>Abstract</p> <p>Background</p> <p>Allele frequency is one of the most important population indices and has been broadly applied to genetic/genomic studies. Estimation of allele frequency using genotypes is convenient but may lose data information and be sensitive to genotyping errors.</p> <p>Results</p> <p>This study utilizes a unified intensity-measuring approach to estimating individual-level allele frequencies for 1,104 and 1,270 samples genotyped with the single-nucleotide-polymorphism arrays of the Affymetrix Human Mapping 100K and 500K Sets, respectively. Allele frequencies of all samples are estimated and adjusted by coefficients of preferential amplification/hybridization (CPA), and large ethnicity-specific and cross-ethnicity databases of CPA and allele frequency are established. The results show that using the CPA significantly improves the accuracy of allele frequency estimates; moreover, this paramount factor is insensitive to the time of data acquisition, effect of laboratory site, type of gene chip, and phenotypic status. Based on accurate allele frequency estimates, analytic methods based on individual-level allele frequencies are developed and successfully applied to discover genomic patterns of allele frequencies, detect chromosomal abnormalities, classify sample groups, identify outlier samples, and estimate the purity of tumor samples. The methods are packaged into a new analysis tool, ALOHA (<b>A</b>llele-frequency/<b>L</b>oss-<b>o</b>f-<b>h</b>eterozygosity/<b>A</b>llele-imbalance).</p> <p>Conclusions</p> <p>This is the first time that these important genetic/genomic applications have been simultaneously conducted by the analyses of individual-level allele frequencies estimated by a unified intensity-measuring approach. We expect that additional practical applications for allele frequency analysis will be found. The developed databases and tools provide useful resources for human genome analysis via high-throughput single-nucleotide-polymorphism arrays. The ALOHA software was written in R and R GUI and can be downloaded at <url>http://www.stat.sinica.edu.tw/hsinchou/genetics/aloha/ALOHA.htm</url>.</p

    An integrated analysis tool for analyzing hybridization intensities and genotypes using new-generation population-optimized human arrays

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    The cross-sample plot of the multipoint LOH/LCSH analyses of the three samples used in Fig. 5. The plot comprises four panels: (a) The top-left panel is a cross-sample and cross-chromosome plot. The vertical axis is the index of study samples, and the horizontal axis is the physical position (Mb) on each of the 23 chromosomes. The blue and red bars represent SNPs without and with LOH/LSCH, respectively. (b) The top-right panel is a histogram of cross-chromosome aberration frequency. The vertical axis is the index of study samples, and the horizontal axis is the cross-chromosome aberration frequency of the corresponding samples. The pink (skyblue) background represents that the genetic gender of a sample is female (male). The histogram represents the aberration frequency of LOH/LCSH SNPs across the chromosomes of the corresponding samples. (c) The bottom-left panel is a histogram of the cross-sample aberration frequency. The vertical axis is the cross-sample aberration frequency of a SNP, and the horizontal axis is the physical position (Mb) on each of the 23 chromosomes. The purple line represents the aberration proportion of samples carrying the SNPs with LOH/LCSH. (d) The bottom-right panel is the legend of the genetic gender that is used in panel (b), where the pink (skyblue) background represents that the genetic gender of a sample is female (male). (TIFF 1656 kb

    A 9 bp cis-element in the promoters of class I small heat shock protein genes on chromosome 3 in rice mediates L-azetidine-2-carboxylic acid and heat shock responses

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    In rice, the class I small heat shock protein (sHSP-CI) genes were found to be selectively induced by L-azetidine-2-carboxylic acid (AZC) on chromosome 3 but not chromosome 1. Here it is shown that a novel cis-responsive element contributed to the differential regulation. By serial deletion and computational analysis, a 9 bp putative AZC-responsive element (AZRE), GTCCTGGAC, located between nucleotides –186 and –178 relative to the transcription initiation site of Oshsp17.3 was revealed. Deletion of this putative AZRE from the promoter abolished its ability to be induced by AZC. Moreover, electrophoretic mobility shift assay (EMSA) revealed that the AZRE interacted specifically with nuclear proteins from AZC-treated rice seedlings. Two AZRE–protein complexes were detected by EMSA, one of which could be competed out by a canonical heat shock element (HSE). Deletion of the AZRE also affected the HS response. Furthermore, transient co-expression of the heat shock factor OsHsfA4b with the AZRE in the promoter of Oshsp17.3 was effective. The requirement for the putative AZRE for AZC and HS responses in transgenic Arabidopsis was also shown. Thus, AZRE represents an alternative form of heat HSE, and its interaction with canonical HSEs through heat shock factors may be required to respond to HS and AZC
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