504 research outputs found

    Experiments, Surveys and the Use of Representative Samples as Reference Data

    Get PDF
    During the last two decades, laboratory experiments have come into increasing prominence and constitute a popular method of research to examine behavioral outcomes and social preferences. However, it has been debated whether results from these experiments can be extrapolated to the real world and whether, for example, sample selection into the experiment might constitute a major shortcoming of this methodology. This note discusses potential benefits of combining experimental methods and representative datasets as a means to overcome some of the limitations of lab experiments. We also outline how large representative surveys can serve as reference data for researchers collectingexperiments, survey, representativity

    Experiments, Surveys and the Use of Representative Samples as Reference Data

    Full text link
    "During the last two decades, laboratory experiments have come into increasing prominence and constitute a popular method of research to examine behavioral outcomes and social preferences. However, it has been debated whether results from these experiments can be extrapolated to the real world and whether, for example, sample selection into the experiment might constitute a major shortcoming of this methodology. This note discusses potential benefits of combining experimental methods and representative datasets as a means to overcome some of the limitations of lab experiments. We also outline how large representative surveys can serve as reference data for researchers collecting their own datasets in order to explore potential sample selection biases." [author's abstract

    Towards an Economic Justification of Service Oriented Architectures - Measuring the Financial Impact

    Get PDF
    Service oriented architectures (SOA) herald a new generation of application systems. Whereas current systems were to be chosen and operated as self-contained systems of individual vendors, service oriented architectures allow for integrating application functionality from different sources internal or external to a company according to individual needs within a specific context. Vendors of ERP systems are developing service oriented product variants and intermediaries for trading services over the internet have established already. Therefore, companies are increasingly confronted with the question, to what extend the adoption of SOA turns out to be a profitable venture. As out-payments can be well estimated, the question is: “What is the actual economic value to be gained by utilizing SOA-enabled systems and what monetary consequences are associated with a SOA adoption?” With this contribution we present an approach to measure the financial impact of SOA based on conceptual process models

    Clinical and radiological features of pulmonary disease due to culture-positive M. tuberculosis or nontuberculous mycobacteria in South African gold miners.

    Get PDF
    Pulmonary mycobacterial disease may be due to Mycobacterium tuberculosis or nontuberculous mycobacteria (NTM

    From Missing Links to New Records: A Series of Novel Polychlorine Anions

    Get PDF
    Herein we report the synthesis and structural characterization of four novel polychloride compounds. The compounds [CCl(NMe2)2][Cl(Cl2)3] and [NPr4][Cl(Cl2)4] have been obtained from the reaction of the corresponding chloride salts with elemental chlorine at low temperature. They are the missing links in the series of polychloride monoanions [Cl(Cl)n]− (n=1–6). Additionally, the reaction of decamethylferrocene with elemental chlorine was studied yielding [Cp*2Fe]2[Cl20], which contains the largest known polychloride [Cl20]2− to date, and [Cp*2Fe][Cl(Cl2)4(HF)], which is the first example of a polychloride‐HF network stabilized by strong hydrogen and halogen bonding. All compounds have been characterized by single‐crystal X‐ray diffraction, Raman spectroscopy and quantum‐chemical calculations

    Expression of the ???6 integrin promotes migration and invasion in squamous carcinoma cells

    Get PDF
    The integrin αvβ6 is a fibronectin receptor whose expression is not detectable on normal oral epithelium but is increased significantly in healing and in oral epithelial dysplasia and oral squamous cell carcinoma, suggesting it may promote changes associated with tumor development. To study whether αvβ6 may drive invasive behavior we have used transfection and retroviral infection to create a panel of epithelial cell lines expressing various levels of αvβ6. We report that increased expression of αvβ6 in malignant keratinocytes promotes invasion and leads to an increased capacity for migration towards fibronectin. αvβ6 expression may have a significant role in contributing to the malignant behavior of epithelial cells

    Dasatinib reverses Cancer-associated Fibroblasts (CAFs) from primary Lung Carcinomas to a Phenotype comparable to that of normal Fibroblasts

    Get PDF
    Cancer associated fibroblasts (CAFs) play a critical role for growth, invasion, and metastasis of cancer. Therefore, targeting CAFs with small molecule inhibitors may be an attractive anti-tumor strategy. The current study aims to identify small molecule kinase inhibitors affecting CAF's growth and to characterize the biological effects of active compounds on primary CAFs from lung cancer. We screened two individual CAF strains for their sensitivity to a panel of 160 kinase inhibitors. Five kinase inhibitors were identified inhibiting more than 50% of the growth of both cell lines. Three of them were inhibitors of PDGFR at nanomolar concentrations. Therefore, we further tested the FDA approved PDGFR inhibitors Dasatinib, Nilotinib, Sorafenib, and Imatinib. All 37 CAF strains investigated were highly sensitive to Dasatinib at clinically relevant concentrations. Imatinib was slightly less effective, whereas the inhibitory effects of Nilotinib and Sorafenib were significantly less pronounced

    IL-22 mediates goblet cell hyperplasia and worm expulsion in intestinal helminth infection.

    Get PDF
    Type 2 immune responses are essential in protection against intestinal helminth infections. In this study we show that IL-22, a cytokine important in defence against bacterial infections in the intestinal tract, is also a critical mediator of anti-helminth immunity. After infection with Nippostrongylus brasiliensis, a rodent hookworm, IL-22-deficient mice showed impaired worm expulsion despite normal levels of type 2 cytokine production. The impaired worm expulsion correlated with reduced goblet cell hyperplasia and reduced expression of goblet cell markers. We further confirmed our findings in a second nematode model, the murine whipworm Trichuris muris. T.muris infected IL-22-deficient mice had a similar phenotype to that seen in N.brasiliensis infection, with impaired worm expulsion and reduced goblet cell hyperplasia. Ex vivo and in vitro analysis demonstrated that IL-22 is able to directly induce the expression of several goblet cell markers, including mucins. Taken together, our findings reveal that IL-22 plays an important role in goblet cell activation, and thus, a key role in anti-helminth immunity
    corecore