4,528 research outputs found
Recent Development on Information System Capabilities and Sustainable Competitive Advantages: A Research Model, Review and Directions for Future Research
In today's competitive environment, maintaining a competitive advantage to achieve high performance is a significant challenge for businesses. To succeed, organizations must not only develop competencies in their focus areas but also be able to adapt, change, and realign those competencies in a dynamic and competitive corporate environment. As a result, information system (IS) capabilities are growing in significance as a strategic element that supports the development of competitive advantages and organizational survival. By examining the gap from the prior research, this study intends to answer questions about the link between information system (IS) related capabilities and the sustainable competitive advantages of an organization. The dimensions of information system capabilities (Personnel capability, Administrative capability, Infrastructure capability, and Information management capability) are factors that could explain a firm's sustainable competitive advantage and the theory of dynamic capability is used as the guiding theory, as guidance, and to support the conceptual framework. This will clarify how firms may use their resources and capabilities to boost the effectiveness and utilization of information systems (IS) in daily operations, processes, and people's performance
Legal and Regulatory Challenges of the Sharing Economy
This policy brief examines the issues raised by the emergence of huge companies such as Uber in the UK and Didi in China that operate in the so-called ‘sharing economy’. The business model of these companies represents a fundamental realignment of the relations between capital and labour, and raises questions about the liability for public safety, the need to preserve the jobs of traditional ‘offline’ operators, and the unfair use of consumers’ personal data. The authors examine recent cases involving Uber and Transport for London which saw the company’s licence temprarily suspended, and the 2016 ruling in favour of two Uber drivers which recognized them as employees under UK employment law, rather than as independent contractors or self-employed. The brief concludes that the rapid expansion and diversification of the sharing economy requires carefully crafted measures that can be implemented by existing regulatory bodies, or by new and alternative forms of regulators altogether
Discovering monotonic stemness marker genes from time-series stem cell microarray data
© 2015 Wang et al.; licensee BioMed Central Ltd. Background: Identification of genes with ascending or descending monotonic expression patterns over time or stages of stem cells is an important issue in time-series microarray data analysis. We propose a method named Monotonic Feature Selector (MFSelector) based on a concept of total discriminating error (DEtotal) to identify monotonic genes. MFSelector considers various time stages in stage order (i.e., Stage One vs. other stages, Stages One and Two vs. remaining stages and so on) and computes DEtotal of each gene. MFSelector can successfully identify genes with monotonic characteristics.Results: We have demonstrated the effectiveness of MFSelector on two synthetic data sets and two stem cell differentiation data sets: embryonic stem cell neurogenesis (ESCN) and embryonic stem cell vasculogenesis (ESCV) data sets. We have also performed extensive quantitative comparisons of the three monotonic gene selection approaches. Some of the monotonic marker genes such as OCT4, NANOG, BLBP, discovered from the ESCN dataset exhibit consistent behavior with that reported in other studies. The role of monotonic genes found by MFSelector in either stemness or differentiation is validated using information obtained from Gene Ontology analysis and other literature. We justify and demonstrate that descending genes are involved in the proliferation or self-renewal activity of stem cells, while ascending genes are involved in differentiation of stem cells into variant cell lineages.Conclusions: We have developed a novel system, easy to use even with no pre-existing knowledge, to identify gene sets with monotonic expression patterns in multi-stage as well as in time-series genomics matrices. The case studies on ESCN and ESCV have helped to get a better understanding of stemness and differentiation. The novel monotonic marker genes discovered from a data set are found to exhibit consistent behavior in another independent data set, demonstrating the utility of the proposed method. The MFSelector R function and data sets can be downloaded from: http://microarray.ym.edu.tw/tools/MFSelector/
Kinetic roughening of ion-sputtered Pd(001) surface: Beyond the Kuramoto-Sivashinsky model
The kinetic roughening of Ar+ ion-sputtered Pd(001) surface was investigated. The facet formation on the sputtered surface was studied by tracing the extradiffraction peaks or satellites around the diffraction peaks corresponding to the sample surface. The morphological evolution of the sputtered Pd(001) surface was also investigated by an scanning tunneling microscopy (STM). It was shown that the nanoscale adatom islands form and grow with increasing sputter time.open313
Spinons and triplons in spatially anisotropic frustrated antiferromagnets
The search for elementary excitations with fractional quantum numbers is a
central challenge in modern condensed matter physics. We explore the
possibility in a realistic model for several materials, the spin-1/2 spatially
anisotropic frustrated Heisenberg antiferromagnet in two dimensions. By
restricting the Hilbert space to that expressed by exact eigenstates of the
Heisenberg chain, we derive an effective Schr\"odinger equation valid in the
weak interchain-coupling regime. The dynamical spin correlations from this
approach agree quantitatively with inelastic neutron measurements on the
triangular antiferromagnet Cs_2CuCl_4. The spectral features in such
antiferromagnets can be attributed to two types of excitations: descendents of
one-dimensional spinons of individual chains, and coherently propagating
"triplon" bound states of spinon pairs. We argue that triplons are generic
features of spatially anisotropic frustrated antiferromagnets, and arise
because the bound spinon pair lowers its kinetic energy by propagating between
chains.Comment: 16 pages, 6 figure
Molecular basis of FIR-mediated c-myc transcriptional control
The far upstream element (FUSE) regulatory system promotes a peak in the concentration of c-Myc during cell cycle. First, the FBP transcriptional activator binds to the FUSE DNA element upstream of the c-myc promoter. Then, FBP recruits its specific repressor (FIR), which acts as an on/off transcriptional switch. Here we describe the molecular basis of FIR recruitment, showing that the tandem RNA recognition motifs of FIR provide a platform for independent FUSE DNA and FBP protein binding and explaining the structural basis of the reversibility of the FBP-FIR interaction. We also show that the physical coupling between FBP and FIR is modulated by a flexible linker positioned sequentially to the recruiting element. Our data explain how the FUSE system precisely regulates c-myc transcription and suggest that a small change in FBP-FIR affinity leads to a substantial effect on c-Myc concentration.MRC Grant-in-aid U11757455
Wall roughness induces asymptotic ultimate turbulence
Turbulence is omnipresent in Nature and technology, governing the transport
of heat, mass, and momentum on multiple scales. For real-world applications of
wall-bounded turbulence, the underlying surfaces are virtually always rough;
yet characterizing and understanding the effects of wall roughness for
turbulence remains a challenge, especially for rotating and thermally driven
turbulence. By combining extensive experiments and numerical simulations, here,
taking as example the paradigmatic Taylor-Couette system (the closed flow
between two independently rotating coaxial cylinders), we show how wall
roughness greatly enhances the overall transport properties and the
corresponding scaling exponents. If only one of the walls is rough, we reveal
that the bulk velocity is slaved to the rough side, due to the much stronger
coupling to that wall by the detaching flow structures. If both walls are
rough, the viscosity dependence is thoroughly eliminated in the boundary layers
and we thus achieve asymptotic ultimate turbulence, i.e. the upper limit of
transport, whose existence had been predicted by Robert Kraichnan in 1962
(Phys. Fluids {\bf 5}, 1374 (1962)) and in which the scalings laws can be
extrapolated to arbitrarily large Reynolds numbers
The impact of young age on cancer-specific and non-cancer-related survival after surgery for colorectal cancer: 10-year follow-up
<b>Background</b>: It has been reported that although young patients present with more advanced disease, when adjusted for stage, cancer-specific survival is not different after surgery for colorectal cancer. However, few studies have examined non-cancer survival in young patients and 10-year survival has rarely been reported. Moreover, the largest study included patients of old age as a comparator. The aim of this study was to compare cancer-specific and non-cancer-related survival at 10 years in a young age cohort and a middle age cohort in patients undergoing surgery for colorectal cancer.
<b>Methods</b>: Two thousand and seventy seven patients who underwent surgery for colorectal cancer between 1991 and 1994 in 11 hospitals in Scotland were included in the study. Ten-year cancer-specific and non-cancer-related survival and the hazard ratios (HR) were calculated according to age groups (<45/45–54/55–64/65–74 years).
<b>Results</b>: On follow-up, 1066 patients died of their cancer and 369 died of non-cancer-related causes. At 10 years, overall survival was 32%, cancer-specific was 45%, and non-cancer-related survival was 72%. On multivariate analysis of all factors, sex (HR 0.77, 95% CI 0.68–0.88, P<0.001), mode of presentation (HR 1.64, 95% CI 1.44–1.87, P<0.01), Dukes' stage (HR 2.69, 95% CI 2.49–2.90, P<0.001), and specialisation (HR 1.24, 95% CI 1.04–1.44, P<0.01) were independently associated with cancer-specific survival. On multivariate analysis of all factors, age (HR 2.46, 2.04–2.97, P<0.001), sex (HR 0.56, 0.45–0.70, P<0.001), and deprivation (HR 1.16, 1.10–1.24, P<0.001) were independently associated with non-cancer-related survival.
<b>Conclusion</b>: The results of this study confirm that young age does not have a negative impact on cancer-specific survival. Moreover, they show that, with 10-year follow-up, young age does not have a negative impact on non-cancer-related survival
GeneBins: a database for classifying gene expression data, with application to plant genome arrays
BACKGROUND: To interpret microarray experiments, several ontological analysis tools have been developed. However, current tools are limited to specific organisms. RESULTS: We developed a bioinformatics system to assign the probe set sequences of any organism to a hierarchical functional classification modelled on KEGG ontology. The GeneBins database currently supports the functional classification of expression data from four Affymetrix arrays; Arabidopsis thaliana, Oryza sativa, Glycine max and Medicago truncatula. An online analysis tool to identify relevant functions is also provided. CONCLUSION: GeneBins provides resources to interpret gene expression results from microarray experiments. It is available a
Quercetin prevents progression of disease in elastase/LPS-exposed mice by negatively regulating MMP expression
Abstract Background Chronic obstructive pulmonary disease (COPD) is characterized by chronic bronchitis, emphysema and irreversible airflow limitation. These changes are thought to be due to oxidative stress and an imbalance of proteases and antiproteases. Quercetin, a plant flavonoid, is a potent antioxidant and anti-inflammatory agent. We hypothesized that quercetin reduces lung inflammation and improves lung function in elastase/lipopolysaccharide (LPS)-exposed mice which show typical features of COPD, including airways inflammation, goblet cell metaplasia, and emphysema. Methods Mice treated with elastase and LPS once a week for 4 weeks were subsequently administered 0.5 mg of quercetin dihydrate or 50% propylene glycol (vehicle) by gavage for 10 days. Lungs were examined for elastance, oxidative stress, inflammation, and matrix metalloproteinase (MMP) activity. Effects of quercetin on MMP transcription and activity were examined in LPS-exposed murine macrophages. Results Quercetin-treated, elastase/LPS-exposed mice showed improved elastic recoil and decreased alveolar chord length compared to vehicle-treated controls. Quercetin-treated mice showed decreased levels of thiobarbituric acid reactive substances, a measure of lipid peroxidation caused by oxidative stress. Quercetin also reduced lung inflammation, goblet cell metaplasia, and mRNA expression of pro-inflammatory cytokines and muc5AC. Quercetin treatment decreased the expression and activity of MMP9 and MMP12 in vivo and in vitro, while increasing expression of the histone deacetylase Sirt-1 and suppressing MMP promoter H4 acetylation. Finally, co-treatment with the Sirt-1 inhibitor sirtinol blocked the effects of quercetin on the lung phenotype. Conclusions Quercetin prevents progression of emphysema in elastase/LPS-treated mice by reducing oxidative stress, lung inflammation and expression of MMP9 and MMP12.http://deepblue.lib.umich.edu/bitstream/2027.42/78260/1/1465-9921-11-131.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78260/2/1465-9921-11-131.pdfPeer Reviewe
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