1,970 research outputs found
Price Dispersion and Differentiation in Online Travel: An Empirical Investigation
Previous research has examined whether price dispersion exists in theoretically highly efficient Internet markets. However, much of the previous work has been focused on industries with low cost and undifferentiated products. In this paper, we examine the presence of price dispersion and product differentiation using data on the airline ticket offerings of online travel agents (OTAs). We find that different OTAs offer tickets with substantially different prices and characteristics when given the same customer request. Some of this variation appears to be due to product differentiation—different OTAs specialize by systematically offering different trade-offs between ticket price and ticket quality (minimizing the number of connections, matching requested departure and return time). However, even after accounting for differences in ticket quality, ticket prices vary by as much as 18% across OTAs. In addition, OTAs return tickets that are strictly inferior to the ticket offered by another OTA for the same request between 2.2% and 28% of the time. Overall, this suggests the presence of both price dispersion and product differentiation in the online travel market
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Design and development of a low-cost, electricity-generating cooking Score-Stoveâ„¢
SCORE (www.score.uk.com) a US120 with 20 Watts of electricity 60 million people would afford the stove. At the lower-cost target of $40 and 100 Watts it would be affordable to over 1 billion people. In November 2010, a wood burning Score-Stoveâ„¢ prototype successfully developed 23 watts of electricity based on a planar Thermo-Acoustic Engine (TAE) [2],[3],[4],[5],[6] design, indicating that the new Score-Stoveâ„¢ is now ready to be engaged with manufacturers to gear up for volume production, and therefore to meet the social and cooking requirements of the rural poor people. The development to a large-volume, easy to manufacture, low-cost TAE cooking stove using elements of the formal design methodologies of BS 7000 and TRIZ are discussed. By breaking down the system requirements into cost targets for each module, performing rig testing, and design refinements it is believed that the upper-cost target is achievable with the right level of investment
Improving trial recruitment through improved communication about patient and public involvement : an embedded cluster randomised recruitment trial
Background: Evidence is emerging that patient and public involvement in research (PPIR) may improve recruitment into randomised controlled trials, but the best methods to achieve improvement are unclear. Although many trials use PPIR to improve design and conduct, many do not communicate their use of PPIR clearly to potential participants. Directly communicating PPIR might encourage participation through increased patient confidence and trust in a trial. We aimed to develop and evaluate the impact on recruitment an intervention communicating PPIR in a trial to potential participants. Methods: This study was embedded in EQUIP, a cluster randomised controlled trial which allocated mental health teams in England to either a training intervention group to improve service user and carer involvement in care planning, or to a control group (no training). We conducted a cluster randomised trial of a recruitment intervention communicating PPIR, embedded within the EQUIP trial. The principles underlying the intervention were informed by a systematic review and a workshop that included mental health service users and trialists. Working with EQUIP PPIR partners (service users and carers) we developed the intervention using a leaflet to advertise the nature and function of the PPIR. Professional graphic design optimised readability and impact. Patients identified as potentially eligible for EQUIP were randomised to receive the leaflet or not, alongside the standard trial information. The primary outcome was the proportion of participants enrolled in EQUIP. The secondary outcome was the proportion expressing interest in taking part. Results: 34 clusters (mental health teams) were recruited, and 8182 potential participants were randomised. Preliminary analyses show that for the primary outcome, 4% of patients receiving the PPIR leaflet were enrolled vs. 5.3% in the control group. For the secondary outcome 7.3% of potential participants receiving the PPIR leaflet responded positively to the invitation to participate, vs. 7.9% in the control group. Future analyses will be by intention-to-treat and use logistic regression to estimate between-group odds ratios (ORs) and corresponding 95% confidence intervals. A planned secondary analysis will explore whether the impact of the intervention is moderated by age and gender. Conclusion: In preliminary analysis of this large trial, communicating PPIR demonstrated no benefits for improving the numbers of potential participants expressing interest in the trial, and reduced trial enrolment. Our findings contrast with the literature suggesting PPIR benefits recruitment. We will discuss the potential reasons for this finding, along with implications for future recruitment practice and research
Thr 163 Phosphorylation Causes Mcl-1 Stabilization when Degradation is Independent of the Adjacent GSK3-Targeted Phosphodegron, Promoting Drug Resistance in Cancer
The antiapoptotic Bcl-2 family member Mcl-1 is a PEST protein (containing sequences enriched in proline, glutamic acid, serine, and threonine) and is subject to rapid degradation via multiple pathways. Impaired degradation leading to the maintenance of Mcl-1 expression is an important determinant of drug resistance in cancer. Phosphorylation at Thr 163 in the PEST region, stimulated by 12-O-tetradecanoylphorbol acetic acid (TPA)-induced activation of extracellular signal-regulated kinase (ERK), is associated with Mcl-1 stabilization in BL41-3 Burkitt lymphoma cells. This contrasts with the observation that Thr 163 phosphorylation in normal fibroblasts primes glycogen synthase kinase (GSK3)-induced phosphorylation at Ser 159, producing a phosphodegron that targets Mcl-1 for degradation. In the present follow-up studies in BL41-3 cells, Mcl-1 degradation was found to be independent of the GSK3-mediated pathway, providing a parallel to emerging findings showing that Mcl-1 degradation through this pathway is lost in many different types of cancer. Findings in Mcl-1-transfected CHO cells corroborated those in BL41-3 cells in that the GSK3-targeted phosphodegron did not play a major role in Mcl-1 degradation, and a phosphomimetic T163E mutation resulted in marked Mcl-1 stabilization. TPA-treated BL41-3 cells, in addition to exhibiting Thr 163 phosphorylation and Mcl-1 stabilization, exhibited an ∼10-fold increase in resistance to multiple chemotherapeutic agents, including Ara-C, etoposide, vinblastine, or cisplatin. In these cancer cells in which Mcl-1 degradation is not dependent on the GSK3/phosphodegron-targeted pathway, ERK activation and Thr 163 phosphorylation are associated with pronounced Mcl-1 stabilization and drug resistance – effects that can be suppressed by inhibition of ERK activation
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Technical Equivalency Documentation for a Newly Aquired Alpha Spectroscopy System
The response of a recently acquired Canberra{trademark} Alpha Analyst 'Blue' system (Chamber Number's 173-208) used by the Hazards Control, Radiation Safety Section, WBC/Spectroscopy Team has been studied with respect to an existing Canberra system. The existing Canberra system consists of thirty Alpha Analyst dual chambers Model XXXX comprising a total of sixty detectors (Chambers Number's 101-124 and 137-172). The existing chambers were previously compared to an older system consisting of thirty-six Model 7401 alpha spectrometry chambers (Chamber Number's 1-36) Chambers 101-124 and 137-172 are DOELAP accredited. The older system was previously DOELAP accredited for the routine Alpha Spectroscopy program used in LLNL's in vitro bioassay program. The newly acquired Alpha Analyst system operates on a network with software that controls and performs analysis of the current Alpha Analyst system (Chamber Number's 101-124 and 137-172). This exact same software is used for the current system and the newly acquired system and is DOELAP accredited. This document compares results from the existing Alpha System with the newer Alpha Analyst system
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Incomplete inhibition of phosphorylation of 4E-BP1 as a mechanism of primary resistance to ATP-competitive mTOR inhibitors
The mammalian target of rapamycin (mTOR) regulates cell growth by integrating nutrient and growth factor signaling and is strongly implicated in cancer. But mTOR is not an oncogene, and which tumors will be resistant or sensitive to new ATP-competitive mTOR inhibitors now in clinical trials remains unknown. We screened a panel of over 600 human cancer cell lines to identify markers of resistance and sensitivity to the mTOR inhibitor PP242. RAS and PIK3CA mutations were the most significant genetic markers for resistance and sensitivity to PP242, respectively; colon origin was the most significant marker for resistance based on tissue type. Among colon cancer cell lines, those with KRAS mutations were most resistant to PP242, while those without KRAS mutations most sensitive. Surprisingly, cell lines with co-mutation of PIK3CA and KRAS had intermediate sensitivity. Immunoblot analysis of the signaling targets downstream of mTOR revealed that the degree of cellular growth inhibition induced by PP242 was correlated with inhibition of phosphorylation of the translational repressor 4E-BP1, but not ribosomal protein S6. In a tumor growth inhibition trial of PP242 in patient-derived colon cancer xenografts, resistance to PP242 induced inhibition of 4E-BP1 phosphorylation and xenograft growth was again observed in KRAS mutant tumors without PIK3CA co-mutation, compared to KRAS WT controls. We show that, in the absence of PIK3CA co-mutation, KRAS mutations are associated with resistance to PP242 and that this is specifically linked to changes in the level of phosphorylation of 4E-BP1
Pecunia non olet but does rose money smell?: on rose oil prices and moral economy in Isparta, Turkey
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