104,566 research outputs found
Heterogeneity in pure microbial systems: experimental measurements and modeling
Cellular heterogeneity influences bioprocess performance in ways that until date are not completely elucidated. In order to account for this phenomenon in the design and operation of bioprocesses, reliable analytical and mathematical descriptions are required. We present an overview of the single cell analysis, and the mathematical modeling frameworks that have potential to be used in bioprocess control and optimization, in particular for microbial processes. In order to be suitable for bioprocess monitoring, experimental methods need to be high throughput and to require relatively short processing time. One such method used successfully under dynamic conditions is flow cytometry. Population balance and individual based models are suitable modeling options, the latter one having in particular a good potential to integrate the various data collected through experimentation. This will be highly beneficial for appropriate process design and scale up as a more rigorous approach may prevent a priori unwanted performance losses. It will also help progressing synthetic biology applications to industrial scale
Novel and topical business news and their impact on stock market activities
We propose an indicator to measure the degree to which a particular news
article is novel, as well as an indicator to measure the degree to which a
particular news item attracts attention from investors. The novelty measure is
obtained by comparing the extent to which a particular news article is similar
to earlier news articles, and an article is regarded as novel if there was no
similar article before it. On the other hand, we say a news item receives a lot
of attention and thus is highly topical if it is simultaneously reported by
many news agencies and read by many investors who receive news from those
agencies. The topicality measure for a news item is obtained by counting the
number of news articles whose content is similar to an original news article
but which are delivered by other news agencies. To check the performance of the
indicators, we empirically examine how these indicators are correlated with
intraday financial market indicators such as the number of transactions and
price volatility. Specifically, we use a dataset consisting of over 90 million
business news articles reported in English and a dataset consisting of
minute-by-minute stock prices on the New York Stock Exchange and the NASDAQ
Stock Market from 2003 to 2014, and show that stock prices and transaction
volumes exhibited a significant response to a news article when it is novel and
topical.Comment: 8 pages, 6 figures, 2 table
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A conceptual model of enterprise application integration in higher education institutions
Copyright @ 2013 EMCIS.It is eminent that several applications’ systems are deployed at different levels in Higher Education (HE), ranging from academic and administrative to staff and students record systems. Many of these systems suffer from different problems due to the lack of integration such as data redundancy, inconsistency and maintenance cost. Enterprise Application Integration (EAI) can provide substantial benefits to these systems, such as assisting with business process integration, facilitating e-service based transformation and supporting collaborative decision-making. However, some factors that influence EAI adoption process in HE will be defined. This paper introduces a conceptual model to explain the outcome of using EAI in Higher Education Institutions (HEIs). Analyzing the combination of the existing classification of EAI factors with the HE factors will enhance the implementation of EAI in HEI at both organizational and operational levels. A pilot study at King Abdulaziz University (KAU), Kingdom of Saudi Arabia will be presented in this paper to show that the integration of the multiple information systems gives an integrated view to facilitate information access and reuse. Moreover data from different information systems is combined to gain a more comprehensive basis to satisfy the educational needs
Infrastructural Drivers of Online Shopping: An International Perspective
While online shopping expenditures have been increasing in both developed and developing economies, they still account for a small share of total retail sales. Significant differences also exist across countries in the amount of money consumers spend on a per capita basis on online purchases. The authors utilize the conceptual foundations of infrastructural framework to examine the effects of infrastructural drivers on online shopping expenditures in 43 countries. Findings show that per capita telecommunications investments and per capita gross national income are significantly associated with per capita online shopping expenditures. Privacy protection, Internet penetration, and credit card penetration were not significant
The Drosophila Inhibitor of Apoptosis (IAP) DIAP2 Is Dispensable for Cell Survival, Required for the Innate Immune Response to Gram-negative Bacterial Infection, and Can Be Negatively Regulated by the Reaper/Hid/Grim Family of IAP-binding Apoptosis Inducers
Many inhibitor of apoptosis (IAP) family proteins inhibit apoptosis. IAPs contain N-terminal baculovirus IAP repeat domains and a C-terminal RING ubiquitin ligase domain. Drosophila IAP DIAP1 is essential for the survival of many cells, protecting them from apoptosis by inhibiting active caspases. Apoptosis initiates when proteins such as Reaper, Hid, and Grim bind a surface groove in DIAP1 baculovirus IAP repeat domains via an N-terminal IAP-binding motif. This evolutionarily conserved interaction disrupts DIAP1-caspase interactions, unleashing apoptosis-inducing caspase activity. A second Drosophila IAP, DIAP2, also binds Rpr and Hid and inhibits apoptosis in multiple contexts when overexpressed. However, due to a lack of mutants, little is known about the normal functions of DIAP2. We report the generation of diap2 null mutants. These flies are viable and show no defects in developmental or stress-induced apoptosis. Instead, DIAP2 is required for the innate immune response to Gram-negative bacterial infection. DIAP2 promotes cytoplasmic cleavage and nuclear translocation of the NF-{kappa}B homolog Relish, and this requires the DIAP2 RING domain. Increasing the genetic dose of diap2 results in an increased immune response, whereas expression of Rpr or Hid results in down-regulation of DIAP2 protein levels. Together these observations suggest that DIAP2 can regulate immune signaling in a dose-dependent manner, and this can be regulated by IBM-containing proteins. Therefore, diap2 may identify a point of convergence between apoptosis and immune signaling pathways
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