730 research outputs found
Living lab methodology as an assessment tool for mass customization
Mass customization has been regularly used as a growth strategy during the last decades. The strength of this approach stems from offering products adjusted to customers' individual needs, resulting in added value. The latter resides in the word 'custom,' implying unique and utilitarian products allowing for self-expression of the consumer. Researchers and practitioners however predominantly focused on the company's internal processes to optimize mass customization, often resulting in market failure. As a response, a framework with five factors determining the success of mass customization was developed. Additionally, Living Lab methodologies have been used to improve innovation contexts that were too closed. This paper will fill a gap in the literature by demonstrating that the integration of the five-factor framework in the Living Lab methodology is well suited to determine the possible success or failure of a mass-customized product in the market by means of a single case study
Organic acids as cloud condensation nuclei: Laboratory studies of highly soluble and insoluble species
International audienceThe ability of sub-micron-sized organic acid particles to act as cloud condensation nuclei (CCN) has been examined at room temperature using a newly constructed continuous-flow, thermal-gradient diffusion chamber (TGDC). The organic acids studied were: oxalic, malonic, glutaric, oleic and stearic. The CCN properties of the highly soluble acids - oxalic, malonic and glutaric - match very closely Köhler theory predictions which assume full dissolution of the dry particle and a surface tension of the growing droplet equal to that of water. In particular, for supersaturations between 0.3 and 0.6, agreement between the dry particle diameter which gives 50% activation and that calculated from Köhler theory is to within 3nm on average. In the course of the experiments, considerable instability of glutaric acid particles was observed as a function of time and there is evidence that they fragment to some degree to smaller particles. Stearic acid and oleic acid, which are both highly insoluble in water, did not activate at supersaturations of 0.6% with dry diameters up to 140nm. Finally, to validate the performance of the TGDC, we present results for the activation of ammonium sulfate particles that demonstrate good agreement with Köhler theory if solution non-ideality is considered. Our findings support earlier studies in the literature that showed highly soluble organics to be CCN active but insoluble species to be largely inactive
Paracetamol Toxicity: Influence Of Ageing, Frailty, Resveratrol And Sirt1
The objective of this thesis was to help improve the safety of paracetamol for patients of all ages by adding evidence to the body of knowledge on the changing risks of paracetamol toxicity in ageing, frailty and non-acute exposures, and the potential for lifespan and healthspan increasing interventions to provide novel mechanisms of paracetamol hepatotoxicity protection. Furthermore, this thesis aimed to investigate the potential of both paracetamol, and lifespan and healthspan interventions in delaying or preventing frailty. Overall the work presented in this thesis used a series of mouse models to contribute to three main findings with clinical significance. Firstly, they demonstrated that there is no increase in susceptibility to paracetamol toxicity in old age or frailty, with either acute, chronic or sub-acute paracetamol exposure. Secondly, they showed that the currently used paracetamol hepatotoxicity therapy, NAC, does not protect against toxicity induced by sub-acute paracetamol exposure. Further studies showed that the mechanism of SIRT1 activation does not provide an alternative protective mechanism. Finally, this thesis found that the lifespan and healthspan increasing interventions of resveratrol and calorie restriction, but not therapeutic paracetamol, were able to delay frailty in aged mice
Switching Intentions of Service Providers and Cultural Orientation
This study performs a cross-cultural comparison to understand how the drivers of switching intentions differ between countries that vary in their long-term orientation (LTO). The authors hypothesize how LTO moderates the influence of the drivers of switching intentions for a mobile phone subscription service. Structural invariance tests between consumer samples of the United States (low LTO) and the Netherlands (high LTO) reveal that, consumers from high LTO nation attribute more importance to relational quality but care less about service recovery in their formation of switching intentions. The theoretical and managerial implications of how differences in time orientation affect the pathways to loyalty are discussed
Heterogeneous oxidation of saturated organic aerosols by hydroxyl radicals: uptake kinetics, condensed-phase products, and particle size change
International audienceThe kinetics and reaction mechanism for the heterogeneous oxidation of saturated organic aerosols by gas-phase OH radicals were investigated under NOx-free conditions. The reaction of 150 nm diameter Bis(2-ethylhexyl) sebacate (BES) particles with OH was studied as a proxy for chemical aging of atmospheric aerosols containing saturated organic matter. An aerosol reactor flow tube combined with an Aerodyne time-of-flight aerosol mass spectrometer (ToF-AMS) and scanning mobility particle sizer (SMPS) was used to study this system. Hydroxyl radicals were produced by 254 nm photolysis of O3 in the presence of water vapour. The kinetics of the heterogeneous oxidation of the BES particles was studied by monitoring the loss of a mass fragment of BES with the ToF-AMS as a function of OH exposure. We measured an initial OH uptake coefficient of ?0=1.3 (±0.4), confirming that this reaction is highly efficient. The density of BES particles increased by up to 20% of the original BES particle density at the highest OH exposure studied, consistent with the particle becoming more oxidized. Electrospray ionization mass spectrometry analysis showed that the major particle-phase reaction products are multifunctional carbonyls and alcohols with higher molecular weights than the starting material. Volatilization of oxidation products accounted for a maximum of 17% decrease of the particle volume at the highest OH exposure studied. Tropospheric organic aerosols will become more oxidized from heterogeneous photochemical oxidation, which may affect not only their physical and chemical properties, but also their hygroscopicity and cloud nucleation activity
New horizons or a strategic mirage? Artist-led-distribution versus alliance strategy in the video game industry
In this paper we contribute to the debate between researchers who argue that the emergence of online distribution allows content producers in the creative industries to bypass powerful publishers and distributors, and other researchers who argue that this strategy cannot succeed without the complementary assets that these intermediaries provide. We use a case study of the Dutch Video Game Developer (DVGD) bringing to market an identical game using two different but comparable distribution channels as a quasi-experiment: in the first release DVGD used online distribution to reach consumers directly, whereas in the second it used an alliance with an established video game publisher. We find that, while the alliance required DVGD to share with the publisher a substantial fraction of the value appropriated by the game, the alliance strategy resulted in greater absolute financial performance and relative market performance compared to the self-publishing strategy. We conclude that the differences in performance can be traced back to specialized complementary assets required for successful commercialization
AKARI observations of ice absorption bands towards edge-on young stellar objects
To investigate the composition and evolution of circumstellar ice around low-mass young stellar objects (YSOs), we observed ice absorption bands in the near infrared (NIR) towards eight YSOs ranging from class 0 to class II, among which seven are associated with edge-on disks. We performed slit-less spectroscopic observations using the grism mode of the InfraRed Camera (IRC) on board AKARI, which enables us to obtain full NIR spectra from 2.5 mu m to 5 mu m, including the CO2 band and the blue wing of the H2O band, which are inaccessible from the ground. We developed procedures to carefully process the spectra of targets with nebulosity. The spectra were fitted with polynomial baselines to derive the absorption spectra. The molecular absorption bands were then fitted with the laboratory database of ice absorption bands, considering the instrumental line profile and the spectral resolution of the grism dispersion element. Towards the class 0-I sources (L1527, IRC-L1041-2, and IRAS 04302), absorption bands of H2O, CO2, CO, and XCN are clearly detected. Column density ratios of CO2 ice and CO ice relative to H2O ice are 21-28% and 13-46%, respectively. If XCN is OCN-, its column density is as high as 2-6% relative to H2O ice. The HDO ice feature at 4.1 mu m is tentatively detected towards the class 0-I sources and HV Tau. Non-detections of the CH-stretching mode features around 3.5 mu m provide upper limits to the CH3OH abundance of 26% (L1527) and 42% (IRAS 04302) relative to H2O. We tentatively detect OCS ice absorption towards IRC-L1041-2. Towards class 0-I sources, the detected features should mostly originate in the cold envelope, while CO gas and OCN-could originate in the region close to the protostar, where there are warm temperatures and UV radiation. We detect H2O ice band towards ASR41 and 2MASSJ 1628137-243139, which are edge-on class II disks. We also detect H2O ice and CO2 ice towards HV Tau, HK Tau, and UY Aur, and tentatively detect CO gas features towards HK Tau and UY Aur
Parental perspectives on ECEC settings that foster child well-being: A comparison across nine European countries
Parents play a vital role in identifying children’s needs for support and Early Childhood Education and Care
(ECEC ) features that support children’s well -being.This study examined parental perspectives on features of ECEC that foster young children’s well -being under and above the age of 3 years by interviewing 359 parents across nine European countries (England, Finland, Germany, Greece, Italy, the Netherlands, Norway, Poland, and Portugal).
Results revealed that parental perspectives largely converged with quality features discussed in ECEC research. Process quality features were mentioned more frequently than structural features for all children 0- to 6-years-old in almost all countries. However, care -oriented features were mentioned more frequently for under 3 years, and educational-oriented features were mentioned more frequently for the older group. Regarding structural features, patterns of responses across the two age groups were similar in most countries. Age differences were not more pronounced in countries with a split governance system.info:eu-repo/semantics/publishedVersio
No significant improvement of cardiovascular disease risk indicators by a lifestyle intervention in people with familial hypercholesterolemia compared to usual care: results of a randomised controlled trial
Background: People with Familial Hypercholesterolemia (FH) may benefit from lifestyle changes supporting their primary treatment of dyslipidaemia. This project evaluated the efficacy of an individualised tailored lifestyle intervention on lipids (low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), total cholesterol (TC) and triglycerides), systolic blood pressure, glucose, body mass index (BMI) and waist circumference in people with FH. Methods: Adults with FH (n= 340), recruited from a Dutch cascade screening program, were randomly assigned to either a control group or an intervention group. The personalised intervention consisted of web-based tailored lifestyle advice and personal counselling. The control group received care as usual. Lipids, systolic blood pressure, glucose, BMI, and waist circumference were measured at baseline and after 12 months. Regression analyses were conducted to examine differences between both groups. Results: After 12 months, no significant between-group differences of cardiovascular disease (CVD) risk indicators were observed. LDL-C levels had decreased in both the intervention and control group. This difference between intervention and control group was not statistically significant. Conclusions: This project suggests that an individually tailored lifestyle intervention did not have an additional effect in improving CVD risk indicators among people with FH. The cumulative effect of many small improvements in all indicators on long term CVD risk remains to be assessed in future studies. Trial registration: NTR1899 at ww.trialregister.nl.© 2012 Broekhuizen et al
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