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991.
Sparfloxacin is a new antimicrobial that, while maintaining a good activity against gram negative bacilli, has a better in vitro activity against gram positive bacteria such as S pneumoniae, intracellular pathogens and anaerobic bacteria. The aim of this work was to study the in vitro activity of sparfloxacin against bacteria isolated from patients with community acquired respiratory infections between October 1994 and January 1995. Using the E-test technique, we studied the susceptibility to sparfloxacin, ciprofloxacin, ampicillin, amoxicillin/clavulanic acid, cefuroxime, cefotaxime, erythromycin, methicillin and nalidixic acid of 50 strains of S pneumoniae, 50 strains of H. influenzae, 50 strains of S aureus and 50 strains of S pyogenes. Sparfloxacin was active against 100% of S pneumoniae, H influenzae and S pyogenes strains. Twenty two percent of S aureus strains were resistant and the MIC 90 was 12 micrograms/ml. Sparfloxacin showed the best in vitro activity against H influenzae and S aureus, a similar activity with ampicillin and cefotaxime against S pneumoniae and a similar activity with ampicillin but superior to all other studied antimicrobial against S pyogenes. It is concluded that sparfloxacin is a good antimicrobial for bacteria isolated from patients with respiratory infections.  相似文献   
992.
Introducing ferromagnetism in transition metal dichalcogenides has attracted lots of attention due to the possible applications in spintronics devices. Generally, single magnetic element doping is used to introduce magnetism. However, mostly, weak ferromagnetism is observed. In this work, codoping of two kinds of transition metals (Nb and Co) into WSe2 is used to study its magnetic properties. In detail, single crystal WSe2 is codoped with 4 at% Co and various concentrations of Nb by employing the physical ion implantation method. Raman, X‐ray diffraction and X‐ray photoelectron spectroscopy results reveal the effective substitutional doping of implanted elements (Co and Nb). Magnetic measurements illustrate that both un‐doped and 4 at% Co doped WSe2 show weak ferromagnetism whereas magnetization is strongly enhanced when Co and Nb are codoped into WSe2. The magnetization is comparable with a ferromagnet, which may be attributed to Co, Nb doping and defects. In addition, a large coercivity of ≈1.2 kOe is observed in the 1 at% Nb–4 at% Co codoped WSe2 sample, which may be ascribed to the combined effect of doping‐induced stress, defect‐dictated pinning and anisotropy of Nb? Se bond owing to the charge transfer between Nb and Se ions.  相似文献   
993.
Panagiotis Isigonis  Antreas Afantitis  Dalila Antunes  Alena Bartonova  Ali Beitollahi  Nils Bohmer  Evert Bouman  Qasim Chaudhry  Mihaela Roxana Cimpan  Emil Cimpan  Shareen Doak  Damien Dupin  Doreen Fedrigo  Valrie Fessard  Maciej Gromelski  Arno C. Gutleb  Sabina Halappanavar  Peter Hoet  Nina Jeliazkova  Stphane Jomini  Sabine Lindner  Igor Linkov  Eleonora Marta Longhin  Iseult Lynch  Ineke Malsch  Antonio Marcomini  Espen Mariussen  Jesus M. de la Fuente  Georgia Melagraki  Finbarr Murphy  Michael Neaves  Rolf Packroff  Stefan Pfuhler  Tomasz Puzyn  Qamar Rahman  Elise Rundn Pran  Elena Semenzin  Tommaso Serchi  Christoph Steinbach  Benjamin Trump  Ivana Vinkovi&#x; Vr ek  David Warheit  Mark R. Wiesner  Egon Willighagen  Maria Dusinska 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(36)
Nanotechnologies have reached maturity and market penetration that require nano‐specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)‐by‐Design (SbD) concepts. This paper provides an overview of the state‐of‐the‐art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re‐thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science‐based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally.  相似文献   
994.
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996.
User-interface design lacks expertise in designing nonvisual user interfaces. This is surprising as there are various domains where auditory interfaces have already been proved to be helpful, such as railway information services and reading support for blind persons.

We present a case study concerning the design of a telephone-based interface (TBI). It was realized within the development process of an interaction concept for a modular home automation system. The design was based on requirements gathered in user focus groups and on general guidelines for the design of TBIs. The TBI's evaluation revealed some minor (i.e., easily solved) usability problems. Questionnaires showed a positive ergonomic quality as well as a positive overall appeal. Interestingly, the evaluation indicates a potential to improve hedonic quality (i.e., non-task-related quality aspects). It may be induced by the addition of nonspeech sounds, thereby enriching user experience.  相似文献   
997.
Semantic ambient media are the novel trend in the world of media reaching from the pioneering subareas such as ambient advertising to the new and emerging subareas such as ambient assisted living. They will likely shape the upcoming years in terms of modeling smart environments and also media consumption and interaction. This work analyzes semantic ambient media by considering business models, content and media, interaction design and consumer experience, and methods and techniques that are important to create this new form of media. Discussion is led using the state-of-the-art event of the semantic ambient media, which is the annual international workshop on Semantic Ambient Media Experience (SAME). The study also creates a vision for how ambient media will evolve and how they will look like in the future decade.  相似文献   
998.
In cold climate regions winter conditions significantly influence the performance of stormwater infiltration devices. Frozen soil and water storage by snow changes their operation. In this paper winter operation of a grassed infiltration swale was investigated using on-site and laboratory measurements. The field investigation of a grassed swale at a parking place in an Alpine region showed that the swale fulfilled its function properly. Although the top layer was frozen for some time, the storage capacity of the swale was sufficient to store the precipitation until the conditions improved. The soil attenuated the air temperature, at 20 cm below ground surface the soil was only frozen for one week. winter maintenance proved to be a problem, together with the snow from the parking place a lot of gravel and fine particles were deposited at one end of the swale. This decreased the hydraulic conductivity at that point significantly. The laboratory tests with soil columns showed an increase of flow time through the soil column with decreasing soil moisture content. For soil temperatures below 0 degrees C the hydraulic conductivity was reduced for increasing initial soil moisture contents. All in all the hydraulic conductivity was best around 0 degrees C for all soil water contents. However, also at minus 5 degrees C the coefficient of hydraulic conductivity was always at least above 10(-6) m/s, thus within the range of tolerated hydraulic conductivity specified in the national guidelines. Nevertheless, the handling of the soil was found to have high influence on the results. The results indicate that in the Alpine region infiltration swales operate sufficiently under winter conditions although with decreased performance.  相似文献   
999.
Researchers and managers have found that the use of external knowledge in the process of new product development (NPD) helps to sustain a firm's competitiveness by strengthening its innovative performance. However, little is known about why some firms use external knowledge sources for NPD in an extensive manner while others hardly ever use them. In addition, there is disagreement about which external partners significantly contribute to the innovative performance of a firm as valuable knowledge sources. Based on the resource‐based view (RBV) of the firm and Kitchell's innovation adoption model, this paper expects a firm's innovation culture to have a significant impact on its openness to external knowledge – measured in terms of its collaborative behaviour with five different external partners – and for that behaviour to influence the firm's NPD performance. A sample of 254 technology‐based firms across several industries is used to empirically test the research model with covariance‐based structural equation modeling (SEM). The findings deepen our understanding of the discrepancies between successful pioneering firms active in technology and knowledge sourcing and others being less successful.  相似文献   
1000.
In upper tertiary educational programmes around the world, the new Web-mediated communication practices termed Web 2.0 are introduced as learning activities with the goal of facilitating learning through collaborative knowledge construction. The aim of this paper is to point to discrepancies in the views of learning, knowledge, and the goals of the practice implicit in Web 2.0 and educational practices and to argue that these discrepancies lead to theoretical tensions and practical challenges when Web 2.0 practices are utilized for educational purposes. The article is structured into four main parts: First, Web 2.0 is characterized from a practice perspective. Second, some conceptual discrepancies between the “practice logics” of Web 2.0 and educational practices are identified. Third, the question of transcending the discrepancies is raised through a discussion of related pedagogical strategies. Fourth, it is argued that the conceptual discrepancies bear out in practice as concrete challenges concerning collaboration, evaluation, and the general aim and status of the material produced by students. These challenges are illustrated with examples from the author’s practical experience with Web 2.0-mediated learning activities in eight courses at the BA and MA levels.  相似文献   
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