460 research outputs found

    Switching Intentions of Service Providers and Cultural Orientation

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    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

    Form removal aspects on the waviness parameters for steel sheet in automotive applications : fourier filtering versus polynomial regression

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    Premium car makers attach great importance to the visual appearance of the painted car skin as an indication of product quality. The “orange peel” phenomenon constitutes a major problem here. It is not only depending on the paint’s chemical composition and application method, but also on possible waviness components in the sheet substrate. Therefore one is searching hard for a valuable waviness parameter to quantify the substrate’s fitness for purpose. A technically emerging problem is how to remove the form from the measured signal, which is indeed not significant to the orange peel phenomenon. This paper will compare two commonly used approaches: i.e. Fourier filtering versus polynomial regression and will reveal and quantify some common aspects in terms of wavelengths

    An interferometric study of the low-mass protostar IRAS 16293-2422: small scale organic chemistry

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    Aims: To investigate the chemical relations between complex organics based on their spatial distributions and excitation conditions in the low-mass young stellar objects IRAS 16293-2422 A and B. Methods: Interferometric observations with the Submillimeter Array have been performed at 5''x3'' resolution revealing emission lines of HNCO, CH3CN, CH2CO, CH3CHO and C2H5OH. Rotational temperatures are determined from rotational diagrams when a sufficient number of lines are detected. Results: Compact emission is detected for all species studied here. For HNCO and CH3CN it mostly arises from source A, CH2CO and C2H5OH have comparable strength for both sources and CH3CHO arises exclusively from source B. HNCO, CH3CN and CH3CHO have rotational temperatures >200 K. The (u,v)-visibility data reveal that HNCO also has extended cold emission. Conclusions: The abundances of the molecules studied here are very similar within factors of a few to those found in high-mass YSOs. Thus the chemistry between high- and low-mass objects appears to be independent of luminosity and cloud mass. Bigger abundance differences are seen between the A and B source. The HNCO abundance relative to CH3OH is ~4 times higher toward A, which may be due to a higher initial OCN- ice abundances in source A compared to B. Furthermore, not all oxygen-bearing species are co-existent. The different spatial behavior of CH2CO and C2H5OH compared with CH3CHO suggests that hydrogenation reactions on grain-surfaces are not sufficient to explain the observed gas phase abundances. Selective destruction of CH3CHO may result in the anti-coincidence of these species in source A. These results illustrate the power of interferometric compared with single dish data in terms of testing chemical models.Comment: 11 pages, 15 figures, accepeted by A&

    The effect of unfiltered coffee on potential biomarkers for colonic cancer risk in healthy volunteers: a randomized trial

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    Background: Epidemiologic studies suggest that coffee use might protect against colorectal cancer. Inconsistencies as to the effect of coffee use and colorectal cancer between epidemiologic studies might be related to the type of coffee brew. Objective: We studied the effect of unfiltered coffee consumption on putative biomarkers for colonic cancer risk. Design: A total of 64 healthy volunteers (31 men and 33 women), with a mean age of 43 ± 11 years were randomly assigned to two groups in a crossover design, with two intervention periods of 2 weeks separated by a washout period of 8 weeks. Treatments were 1 L of cafetiere (French press) coffee daily or no coffee. At the end of each intervention period, fasting blood samples, colorectal biopsies and 48 h faeces were collected. Results: No effect of coffee on colorectal cell proliferation, assayed by estimating the Proliferating Cell Nuclear Antigen labelling index, was seen. Additionally, no effects were seen on the concentrations of faecal soluble bile acids and colorectal mucosal glutathione S-transferase activity. However, unfiltered coffee significantly increased the glutathione content in the colorectal mucosa by 8% and in plasma by 15%. Other aminothiols in plasma also increased on coffee. Conclusion: Unfiltered coffee does not influence the colorectal mucosal proliferation rate, but might increase the detoxification capacity and anti-mutagenic properties in the colorectal mucosa through an increase in glutathione concentration. Whether this effect indeed contributes to a lower colon cancer risk remains to be established

    Preliminary report of a gas conditioner to improve operational reliability of cryotherapy in developing countries

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    BACKGROUND: Cryotherapy is a safe, affordable, and effective method of treatment for cervical intraepithelial neoplasia. In some low-resource settings, environmental conditions or qualities of the refrigerant gas can lead to blockage of cryotherapy equipment, terminating treatment. A prototype of a gas conditioner to prevent operational failure was designed, built, and field tested. METHODS: The prototype conditioner device consists of an expansion chamber that filters and dries the refrigerant gas. Users in Peru and Kenya reported on their experience with the prototype conditioner. In Ghana, simulated cryotherapy procedures were used to test the effects of the prototype conditioner, as well as the commonly used "cough technique." RESULTS: Anecdotal reports from field use of the device were favorable. During simulated cryotherapy, the prevalence of blockage during freezing were 0% (0/25) with the device alone, 23.3% (7/30) with the cough technique alone, 5.9% (1/17) with both, and 55.2% (16/29) with neither (Pearson's Chi square = 26.6, df = 3, p < 0.001 (comparison amongst all groups)). CONCLUSION: This prototype design of a cryotherapy gas conditioner is a potential solution for low-resource settings that are experiencing cryotherapy device malfunction

    Illness perception and related behaviour in lower respiratory tract infections—a European study

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    Background. Lower respiratory tract infection (LRTI) is a common presentation in primary care, but little is known about associated patients’ illness perception and related behaviour. Objective. To describe illness perceptions and related behaviour in patients with LRTI visiting their general practitioner (GP) and identify differences between European regions and types of health care system. Methods. Adult patients presenting with acute cough were included. GPs recorded co morbidities and clinical findings. Patients filled out a diary for up to 4 weeks on their symptoms, illness perception and related behaviour. The chi-square test was used to compare proportions between groups and the Mann-Whitney U or Kruskal Wallis tests were used to compare means. Results. Three thousand one hundred six patients from 12 European countries were included. Eighty-one per cent (n = 2530) of the patients completed the diary. Patients were feeling unwell for a mean of 9 (SD 8) days prior to consulting. More than half experienced impairment of normal or social activities for at least 1 week and were absent from work/school for a mean of 4 (SD 5) days. On average patients felt recovered 2 weeks after visiting their GP, but 21% (n = 539) of the patients did not feel recovered after 4 weeks. Twenty-seven per cent (n = 691) reported feeling anxious or depressed, and 28% (n = 702) re-consulted their GP at some point during the illness episode. Reported illness duration and days absent from work/school differed between countries and regions (North-West versus South-East), but there was little difference in reported illness course and related behaviour between health care systems (direct access versus gate-keeping). Conclusion. Illness course, perception and related behaviour in LRTI differ considerably between countries. These finding should be taken into account when developing International guidelines for LRTI and interventions for setting realistic expectations about illness course

    Attenuated AMPA Receptor Expression Allows Glioblastoma Cell Survival in Glutamate-Rich Environment

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    Background: Glioblastoma multiforme (GBM) cells secrete large amounts of glutamate that can trigger AMPA-type glutamate receptors (AMPARs). This commonly results in Na+ and Ca2+-permeability and thereby in excitotoxic cell death of the surrounding neurons. Here we investigated how the GBM cells themselves survive in a glutamate-rich environment. Methods and Findings: In silico analysis of published reports shows down-regulation of all ionotropic glutamate receptors in GBM as compared to normal brain. In vitro, in all GBM samples tested, mRNA expression of AMPAR subunit GluR1, 2 and 4 was relatively low compared to adult and fetal total brain mRNA and adult cerebellum mRNA. These findings were in line with primary GBM samples, in which protein expression patterns were down-regulated as compared to the normal tissue. Furthermore, mislocalized expression of these receptors was found. Sequence analysis of GluR2 RNA in primary and established GBM cell lines showed that the GluR2 subunit was found to be partly unedited. Conclusions: Together with the lack of functional effect of AMPAR inhibition by NBQX our results suggest that down-regulation and afunctionality of AMPARs, enable GBM cells to survive in a high glutamate environment without going into excitotoxic cell death themselves. It can be speculated that specific AMPA receptor inhibitors may protect normal neurons against the high glutamate microenvironment of GBM tumor

    Superconception in mammalian pregnancy can be detected and increases reproductive output per breeding season

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    The concept of superfetation, a second conception during pregnancy, has been controversial for a long time. In this paper we use an experimental approach to demonstrate that female European brown hares (Lepus europaeus) frequently develop a second pregnancy while already pregnant and thereby increase their reproductive success. After a new, successful copulation, we confirmed additional ovulations before parturition in living, late-pregnant females by detecting a second set of fresh corpora lutea using high-resolution ultrasonography. The presence of early embryonic stages in the oviduct, demonstrated by oviduct flushing, next to fully developed fetuses in the uterus is best explained by passage of semen through the late-pregnant uterus; this was confirmed by paternity analysis using microsatellite profiling. Subsequent implantation occurred after parturition. This superfetation, categorized as superconception, significantly increased litter size and permitted females to produce up to 35.4% more offspring per breeding season. It is therefore most likely an evolutionary adaptation
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