165 research outputs found

    Containing the Not-Invented-Here Syndrome in external knowledge absorption and open innovation: The role of indirect countermeasures

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    This paper builds new theory and provides supporting evidence to contain the Not-Invented-Here Syndrome (NIHS) – a persistent decision-making error arising from an attitude-based bias against external knowledge. Conceptually, we draw on the 4i framework of organizational learning to develop a novel process perspective on NIHS. This allows us not only to unpack how and where NIHS impedes organizational learning, but also to identify the key requirements for effective NIHS countermeasures. Importantly, countermeasures fall into two categories: those that seek to change the negative attitude directly (direct NIHS countermeasures) and those that seek to attenuate the behavioral impact of negative attitudes without addressing the attitudes as such (indirect NIHS countermeasures). While the evidence base on direct NIHS countermeasures has grown over the last decade, indirect NIHS countermeasures have received little research attention. To address this gap, we adopt a mixed methods research design composed of two complementary empirical studies – the first qualitative and the second quantitative. Study 1 explores the prevalence of distinct NIHS countermeasures in collaborative R&D practice. Based on 32 interviews and three focus group meetings with R&D employees, we find that a broad array of primarily direct NIHS countermeasures is employed in R&D practice. Study 2 addresses the scarcity of scholarly and managerial insights on indirect NIHS countermeasures by testing the effectiveness of perspective taking as a debiasing technique to contain negative attitudes at the level of the individual. Based on quantitative survey data from 565 global R&D projects, it provides empirical evidence not only for the prevalence and negative effects of NIHS on project success as mediated by external knowledge absorption, but also for the effectiveness of perspective taking as an exemplary indirect NIHS countermeasure

    Impact vaporization and Condensation: Laser Irradiation Experiments with Natural Planetary Materials

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    0000-0002-4414-4917The attached files are the published version of the article from the 49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083), and the open access abstract (Geophysical Research Abstracts, Vol. 20, EGU2018-16223, 2018, EGU General Assembly 2018, © Author(s) 2018. CC Attribution 4.0 license.

    Measuring Time with Minimal Clocks

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    © 2019 Massachusetts Institute of Technology. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1162/artl_a_00303Being able to measure time, whether directly or indirectly, is a significant advantage for an organism. It allows for timely reaction to regular or predicted events, reducing the pressure for fast processing of sensory input. Thus, clocks are ubiquitous in biology. In the present article, we consider minimal abstract pure clocks in different configurations and investigate their characteristic dynamics. We are especially interested in optimally time-resolving clocks. Among these, we find fundamentally diametral clock characteristics, such as oscillatory behavior for purely local time measurement or decay-based clocks measuring time periods on a scale global to the problem. We include also sets of independent clocks (clock bags), sequential cascades of clocks, and composite clocks with controlled dependence. Clock cascades show a condensation effect, and the composite clock shows various regimes of markedly different dynamics.Peer reviewe

    Designing Chatbots for Crises: A Case Study Contrasting Potential and Reality

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    Chatbots are becoming ubiquitous technologies, and their popularity and adoption are rapidly spreading. The potential of chatbots in engaging people with digital services is fully recognised. However, the reputation of this technology with regards to usefulness and real impact remains rather questionable. Studies that evaluate how people perceive and utilise chatbots are generally lacking. During the last Kenyan elections, we deployed a chatbot on Facebook Messenger to help people submit reports of violence and misconduct experienced in the polling stations. Even though the chatbot was visited by more than 3,000 times, there was a clear mismatch between the users’ perception of the technology and its design. In this paper, we analyse the user interactions and content generated through this application and discuss the challenges and directions for designing more effective chatbots

    A sigmoidal fit for pressure-volume curves of idiopathic pulmonary fibrosis patients on mechanical ventilation: clinical implications

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    OBJECTIVE: Respiratory pressure-volume curves fitted to exponential equations have been used to assess disease severity and prognosis in spontaneously breathing patients with idiopathic pulmonary fibrosis. Sigmoidal equations have been used to fit pressure-volume curves for mechanically ventilated patients but not for idiopathic pulmonary fibrosis patients. We compared a sigmoidal model and an exponential model to fit pressure-volume curves from mechanically ventilated patients with idiopathic pulmonary fibrosis. METHODS: Six idiopathic pulmonary fibrosis patients and five controls underwent inflation pressure-volume curves using the constant-flow technique during general anesthesia prior to open lung biopsy or thymectomy. We identified the lower and upper inflection points and fit the curves with an exponential equation, V = A-B.e-k.P, and a sigmoid equation, V = a+b/(1+e-(P-c)/d). RESULTS: The mean lower inflection point for idiopathic pulmonary fibrosis patients was significantly higher (10.5 ± 5.7 cm H2O) than that of controls (3.6 ± 2.4 cm H2O). The sigmoidal equation fit the pressure-volume curves of the fibrotic and control patients well, but the exponential equation fit the data well only when points below 50% of the inspiratory capacity were excluded. CONCLUSION: The elevated lower inflection point and the sigmoidal shape of the pressure-volume curves suggest that respiratory system compliance is decreased close to end-expiratory lung volume in idiopathic pulmonary fibrosis patients under general anesthesia and mechanical ventilation. The sigmoidal fit was superior to the exponential fit for inflation pressure-volume curves of anesthetized patients with idiopathic pulmonary fibrosis and could be useful for guiding mechanical ventilation during general anesthesia in this condition

    Characterisation of nanoparticles by means of high-resolution SEM/EDS in transmission mode

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    Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Published under licence by IOP Publishing Ltd

    Alteration conditions on the CM and CV parent bodies – Insights from hydrothermal experiments with the CO chondrite Kainsaz

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    This study simulates the hydrothermal conditions that existed on carbonaceous chondrite planetesimals in the early solar system. Our experiments are relevant to alteration conditions that existed on the CV parent body and the late stage oxidizing alteration of the CM chondrites. We conducted 11 alteration experiments using chips of the CO3 chondrite Kainsaz. Water was added to each chip and sealed in separate Teflon reaction vessels for 175 days. Samples were altered at different initial water-to-rock ratios (W/R: 0.2–0.8) and temperatures (50 °C and 150 °C). Isotopically doped 17O-rich heavy water (δ17O: +64.5‰) was used in five runs. All samples experienced pronounced alteration under a partially open system environment where gases were able to escape the reaction vessels. The style of alteration (Fe-alkali metasomatism) is similar in all cases. The principal alteration minerals formed are Fe-oxyhydroxides (goethite) and Fe-oxides (magnetite), with smaller quantities of Fe-sulphides. Minor phases formed include fayalite, sulphates (gypsum and Fe-sulphate) and calcite. Nanophase, poorly crystalline phyllosilicates formed in the high-temperature samples but are absent from the low-temperature experiments. In all instances, Mg-rich chondrule silicates remained chemically unaltered although some grains suffered hydrothermal fracture. Chondrule mesostases remained largely unaffected. By contrast, kamacite readily dissolved, acting as a source of Fe and Ni for the fluid phase. A new generation of nanophase Fe-sulphides formed within the matrix, while pre-existing pyrrhotite group sulphides experienced Ni enrichment ( 10 at%) were formed in the 150 °C samples, most likely by sulphidation of taenite. Matrix alteration cemented grains together, reducing porosity. The fine-grained matrix shows highly variable degrees of alteration, with minimally altered matrix in direct contact with regions of heavily altered matrix. Chondrule fine-grained rims (FGRs) were preferentially altered. These textures imply that the unaltered matrix readily reacted with the fluid phase, resulting in an efficient depletion of dissolved ions (Fe2+ and S2-), limiting reactivity until further primary phases were dissolved. At larger length-scales the distribution of heavily altered matrix reveals the presence of large ∼100 µm wide channels that meander through the specimens. Their textures resemble features seen in some CM chondrites and the ungrouped CO-like chondrite MIL 07687. We suggest that alteration fronts developed by sustained rapid reaction of matrix with dissolved cations in solution. Our observations provide a mechanism for the establishment and maintenance of geochemical microenvironments on chondritic asteroids. The effects of open system loss notwithstanding, our experiments demonstrate that more advanced alteration is correlated with higher initial W/R ratios. The use of 17O-rich doped water allowed the isotopic effects of aqueous alteration to be observed. Bulk rock compositions evolved towards the initial water composition, reflecting the incorporation of heavy O into hydrated minerals. Additionally, altered samples shifted in δ18O space, reflecting the competing effects of water–mineral fractionation and mass fractionation due to the preferential escape of isotopically light water

    Fossil micrometeorites from Monte dei Corvi: Searching for dust from the Veritas asteroid family and the utility of micrometeorites as a palaeoclimate proxy

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    We searched late Miocene sedimentary rocks in an attempt to recover fossil micrometeorites derived from the Veritas asteroid family. This study was motivated by the previous identification of a pronounced 3He peak (4-5x above background) within marine sediments with ages between ∼8.5–6.9 Ma ago (Montanari et al., 2017. GSA Bulletin, 129:1357–1376). We processed 118.9 kg of sediment from the Monte dei Corvi beach section (Italy), the global type-section for the Tortonian epoch (11.6–7.2 Ma). Samples were collected both before and within the 3He peak. Although a small number of iron-rich (I-type) fossil micrometeorites were recovered from each horizon studied (Ntotal = 20), there is no clear difference between the pre- and intra- 3He peak samples. All micrometeorites are compositionally similar, and three out of five horizons yielded similar abundances and particle sizes. Micrometeorites extracted from sediments at the base of the 3He peak were exclusively small (ø 3He values were relatively large (ø 3He signature combined with the absence of fossil micrometeorites or extraterrestrial spinels (Boschi et al., 2019, Spec. Pap. Geol. Soc. Am. 542:383–391) unambiguously related to the Veritas event suggests that the Veritas family is composed of highly friable materials that rarely survive on the sea floor to become preserved in the geological record. Our data supports the existing hypothesis that the Veritas asteroid family is an aqueously altered carbonaceous chondrite parent body, one that contains minimal native metal grains or refractory Cr-spinels. The low yield of fossil micrometeorites at Monte dei Corvi is attributed to loss of particles by dissolution whilst they resided on the sea floor but also due to high sedimentation rates leading to dilution of the extraterrestrial dust flux at this site. As with other fossil micrometeorite collections (e.g. Cretaceous chalk [Suttle and Genge, EPSL, 476:132–142]) the I-type spherules have been altered since deposition. In most particles, both magnetite and wüstite remain intact but have been affected by solid state geochemical exchange, characterised by partial leaching of Ni, Co and Cr and implantation of Mn, Mg, Si and Al. In some particles Mn concentrations reach up to 16.6 wt%. Conversely, in some micrometeorites wüstite has been partially dissolved, or even replaced by calcite or ankerite. Finally, we observe evidence for wüstite recrystallisation, forming a second generation of magnetite. This process is suggested to occur by oxidation during residence on the seafloor and has implications for the use of fossil I-type micrometeorites as a potential proxy for probing Earth’s upper atmospheric composition (oxidative capacity) in the geological past. However, solutions to the limitations of post-depositional recrystallisation are suggested. Fossil I-type spherules remain a potential tool for palaeo-climatic studies
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