This paper examines the effect of the freemium strategy on Google Play, an online marketplace for Android mobile applications. By analyzing a large panel data set consisting of 711 ranked mobile ...apps, we found that the freemium strategy is positively associated with increased sales of the paid mobile apps. Positive trial experience as represented by high review rating of the free version of a mobile app leads to higher sales of its paid version, whereas high visibility of the free version of a mobile app as represented by its product rank does not have a significant impact on the sales of its paid version. This finding suggests that although offering a free trial version is a viable way to improve the visibility of a mobile app, offering a quality free app is more important in boosting sales of the paid app. Moreover, we found that the impact of review rating is reduced when the free version is offered, or when the mobile app is a hedonic app, because consumers have the ability to experience the app themselves before purchase. These findings extend understanding of the freemium business model to include a market characterized by simultaneous intramarket competition for both the freemium and paid products and demonstrate how such dynamics may influence sales of the paid products.
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BFBNIB, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Bronchiolitis obliterans syndrome (BOS) is a devastating pulmonary complication affecting long-term survivors of allogeneic hematopoietic cell transplantation. Treatment of BOS with prolonged courses ...of high dose corticosteroids is often associated with significant morbidity. Reducing the exposure to corticosteroids may reduce treatment-related morbidity. Our institution has recently begun to treat patients with emerging therapies in an effort to diminish corticosteroid exposure. We retrospectively reviewed the 6-month corticosteroid exposure, lung function and failure rates in eight patients with newly diagnosed BOS who were treated with a combination of fluticasone, azithromycin and montelukast (FAM) and a rapid corticosteroid taper. These patients were compared with 14 matched historical patients who received high-dose corticosteroids, followed by a standard taper. The median 6-month prednisone exposure in FAM-treated patients was 1819 mg (0-4036 mg) compared with 7163 mg (6551-7829 mg) in the control group (P=0.002). The median forced expiratory volume in 1 s (FEV(1)) change in FAM-treated patients was 2% (-3 to 4% compared with 1% (-4 to 5%) in the control group (P=1.0). Prednisone exposure in FAM patients was one quarter that of a retrospective-matched group of patients, with minimal change in median FEV(1), suggesting that BOS may be spared of the morbidities associated with long-term corticosteroid use by using alternative agents with less side effects.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Tumors are stiff and data suggest that the extracellular matrix stiffening that correlates with experimental mammary malignancy drives tumor invasion and metastasis. Nevertheless, the relationship ...between tissue and extracellular matrix stiffness and human breast cancer progression and aggression remains unclear. We undertook a biophysical and biochemical assessment of stromal-epithelial interactions in noninvasive, invasive and normal adjacent human breast tissue and in breast cancers of increasingly aggressive subtype. Our analysis revealed that human breast cancer transformation is accompanied by an incremental increase in collagen deposition and a progressive linearization and thickening of interstitial collagen. The linearization of collagen was visualized as an overall increase in tissue birefringence and was most striking at the invasive front of the tumor where the stiffness of the stroma and cellular mechanosignaling were the highest. Amongst breast cancer subtypes we found that the stroma at the invasive region of the more aggressive Basal-like and Her2 tumor subtypes was the most heterogeneous and the stiffest when compared to the less aggressive luminal A and B subtypes. Intriguingly, we quantified the greatest number of infiltrating macrophages and the highest level of TGF beta signaling within the cells at the invasive front. We also established that stroma stiffness and the level of cellular TGF beta signaling positively correlated with each other and with the number of infiltrating tumor-activated macrophages, which was highest in the more aggressive tumor subtypes. These findings indicate that human breast cancer progression and aggression, collagen linearization and stromal stiffening are linked and implicate tissue inflammation and TGF beta.
Human tumors are stiff and data suggest that the extracellular matrix stiffening is consistent with experimental mammary tumor models in which stiffness drives tumor invasion and metastasis.
Economic theory provides a unique vantage point from which to examine issues with respect to emerging technologies, where standards and adoption, business process changes and implementation outcomes, ...information security, investments and business value, and industry impact require care and consideration on the part of senior management strategists and financial services leaders. In this article, we examine a new technology application which is coming into its own around the world, in association with the revolution in wireless connectivity: mobile payments. Although there are likely to be nuances and surprises with this technology application, we caution the reader to recognize that many of the same economic forces will be at work as were with other financial services and related technology applications in the past. We apply a robust evaluative framework that permits identification of the relevant stakeholders and applicable theory in the analysis of consumer, firm, business process, market, industrial and social issues. Our findings are intended to guide senior managers in dealing with the economic aspects of mobile payments, and to help identify some important directions for the research.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This randomized study compared the results achieved by concurrent chemoradiotherapy (CRT) versus radiotherapy (RT) alone for nasopharyngeal carcinoma (NPC) with advanced nodal disease.
Patients with ...nonkeratinizing/undifferentiated NPC staged T1-4N2-3M0 were randomized to CRT or RT. Both arms were treated with the same RT technique and dose fractionation. The CRT patients were given cisplatin 100 mg/m2 on days 1, 22, and 43, followed by cisplatin 80 mg/m2 and fluorouracil 1,000 mg/m2/d for 96 hours starting on days 71, 99, and 127.
From 1999 to January 2004, 348 eligible patients were randomly assigned; the median follow-up was 2.3 years. The two arms were well-balanced in all prognostic factors and RT parameters. The CRT arm achieved significantly higher failure-free survival (72% v 62% at 3-year, P = .027), mostly as a result of an improvement in locoregional control (92% v 82%, P = .005). However, distant control did not improve significantly (76% v 73%, P = .47), and the overall survival rates were almost identical (78% v 78%, P = .97). In addition, the CRT arm had significantly more acute toxicities (84% v 53%, P < .001) and late toxicities (28% v 13% at 3-year, P = .024).
Preliminary results confirmed that CRT could significantly improve tumor control, particularly at locoregional sites. However, there was significant increase in the risk of toxicities and no early gain in overall survival. Longer follow-up is needed to confirm the ultimate therapeutic ratio.
The effects of using fumed SiO2 , MCM-41, and SBA-15 as supports for Ru and Ni catalysts on ammonia decomposition were investigated. It was found that the supported catalysts on these siliceous ...materials are more active than those supported on ordinary silica. In general, the supported Ru catalysts are more active than the Ni catalysts, and MCM-41 is the best support material for Ru and Ni. Significant enhancement in activity was observed when the supported Ru catalysts were modified by KOH, but such effect was minimal in the cases of supported Ni catalysts. The results of N 2 adsorption and transmission electron microscopy studies revealed that the Ni particles of Ni/MCM-41(TIE) prepared by template-ion exchange (TIE) method are largely located inside the pores of MCM-41. Compared with the Ni/MCM-41(IMP) catalyst prepared by impregnation method, the Ni/MCM-41(TIE) catalyst exhibited appropriate Ni dispersion and weaker Ni/support interaction, and consequently higher catalytic activity. In terms of the remarkable changes in turnover frequency (TOF) with Ni dispersion on different catalysts, it was demonstrated that NH 3 decomposition over Ni is significantly structure sensitive. Some unique metal clusters similar to B5 active sites should be responsible for the catalytic activities. Preparation methodology has a substantial influence on metal dispersion. For the supported Ni catalysts prepared by the TIE method, the generated metal particles are very small and the constitution of unique active sites becomes unfavorable, which accounts for the apparently lower TOF values.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Context. The galaxy population in the contemporary Universe is characterised by a clear bimodality, blue galaxies with significant ongoing star formation and red galaxies with only a little. The ...migration between the blue and the red cloud of galaxies is an issue of active research. Post starburst (PSB) galaxies are thought to be observed in the short-lived transition phase. Aims. We aim to create a large sample of local PSB galaxies from the Sloan Digital Sky Survey (SDSS) to study their characteristic properties, particularly morphological features indicative of gravitational distortions and indications for active galactic nuclei (AGNs). Another aim is to present a tool set for an efficient search in a large database of SDSS spectra based on Kohonen self-organising maps (SOMs). Methods. We computed a huge Kohonen SOM for ~ 106 spectra from SDSS data release 7. The SOM is made fully available, in combination with an interactive user interface, for the astronomical community. We selected a large sample of PSB galaxies taking advantage of the clustering behaviour of the SOM. The morphologies of both PSB galaxies and randomly selected galaxies from a comparison sample in SDSS Stripe 82 (S82) were inspected on deep co-added SDSS images to search for indications of gravitational distortions. We used the Portsmouth galaxy property computations to study the evolutionary stage of the PSB galaxies and archival multi-wavelength data to search for hidden AGNs. Results. We compiled a catalogue of 2665 PSB galaxies with redshifts z < 0.4, among them 74 galaxies in S82 with EW(Hδ) > 3 Å and z < 0.25. In the colour-mass diagram, the PSB sample is clearly concentrated towards the region between the red and the blue cloud, in agreement with the idea that PSB galaxies represent the transitioning phase between actively and passively evolving galaxies. The relative frequency of distorted PSB galaxies is at least 57% for EW(Hδ) > 5 Å, significantly higher than in the comparison sample. The search for AGNs based on conventional selection criteria in the radio and MIR results in a low AGN fraction of ~ 2–3%. We confirm an MIR excess in the mean SED of the E+A sample that may indicate hidden AGNs, though other sources are also possible.
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FMFMET, NUK, UL, UM, UPUK
Abstract Measurements of three-dimensional displacements in a scaffold implant under uniaxial compression have been obtained by two digital volume correlation (DVC) methods, and compared with those ...obtained from micro-finite element models. The DVC methods were based on two approaches, a local approach which registers independent small volumes and yields discontinuous displacement fields; and a global approach where the registration is performed on the whole volume of interest, leading to continuous displacement fields. A customised mini-compression device was used to perform in situ step-wise compression of the scaffold within a micro-computed tomography (μCT) chamber, and the data were collected at steps of interest. Displacement uncertainties, ranging from 0.006 to 0.02 voxel (i.e. 0.12–0.4 μm), with a strain uncertainty between 60 and 600 μɛ, were obtained with a spatial resolution of 32 voxels using both approaches, although the global approach has lower systematic errors. Reduced displacement and strain uncertainties may be obtained using the global approach by increasing the element size; and using the local approach by increasing the number of intermediary sub-volumes. Good agreements between the results from the DVC measurements and the FE simulations were obtained in the primary loading direction as well as in the lateral directions. This study demonstrates that volumetric strain measurements can be obtained successfully using DVC, which may be a useful tool to investigate mechanical behaviour of porous implants.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The Aligning Science Across Parkinson's (ASAP) initiative was set up to improve understanding of the biology underlying the onset and progression of Parkinson's disease. With an emphasis on open ...science and collaboration, we have assembled a research network led by nearly 100 investigators to explore the pathology of Parkinson's disease, and this network will soon expand to include researchers working on relevant (dys)-functional neural circuits. We have also contributed to large-scale genetics and patient cohort initiatives related to the disease. We hope that these actions, and others planned for the future, will deepen our knowledge of the molecular mechanisms underlying the origin and evolution of Parkinson's disease and, ultimately, contribute to the development of novel therapies.
The Aligning Science Across Parkinson's (ASAP) initiative is building an international network of researchers to improve our understanding of the biology underlying Parkinson's disease. Developing a ...better understanding of how the disease originates and progresses will, we hope, lead to new therapies. The ASAP initiative will incentivize collaboration between the existing PD research community and other researchers and will be committed to open-science practices.
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