182 research outputs found

    Didactic Conception Of Serious Games: On The Linking Of Game And Learning Offers

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    Serious Games versuchen Spielen mit Lernen zu verbinden. Der Beitrag problematisiert die Machbarkeit einer solchen Verknüpfung in digitalen Welten und diskutiert verschiedene didaktische Konzepte einer Nutzbarmachung digitaler Spiele für das Lernen und Lehren. Ausgehend von einer Analyse des Erlernens von Spielen werden drei didaktische Konzepte von Serious Games im Hinblick auf ihre didaktischen Potenziale untersucht: (1) der unmittelbare Transfer von Wissen, das im Spiel erworben wird (keine zusätzliche Didaktisierung), (2) Didaktisierung durch Einbettung des Spiels in einer Lernsituation oder (3) Didaktisierung durch Einbettung von Lernaufgaben in ein Spiel. Ergebnisse zur Nutzung von Spielen, bei denen Lernaufgaben in eine Spielwelt eingebettet sind, zeigen, dass Personen die Aufnahme von Wissen in einem expliziten Lernmodus eher zu reduzieren versuchen, um möglichst zügig wieder in den Spielmodus zu wechseln. Diskutiert werden die Konsequenzen dieser Problematik für die didaktische Konzeption von Serious Games.Serious games try to combine playing with learning. The article problematises the feasibility of such a link in digital worlds and discusses various didactic concepts of making digital games usable for learning and teaching. Based on an analysis of the learning of games, three didactic concepts of serious games are examined with regard to their didactic potentials: (1) the direct transfer of knowledge acquired in the game (no additional didacticisation), (2) didacticisation by embedding the game in a learning situation or (3) didacticisation by embedding learning tasks in a game. Results on the use of games in which learning tasks are embedded in a game world show that people tend to try to reduce the absorption of knowledge in an explicit learning mode in order to switch back to the game mode as quickly as possible. The consequences of this problem for the didactic conception of serious games are discussed

    Is adherence therapy an effective adjunct treatment for patients with schizophrenia spectrum disorders? A systematic review and meta-analysis

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    Background Poor adherence to medication in schizophrenia spectrum disorders leads to inadequate symptom control. Adherence therapy (AT) is an intervention that seeks to reduce patients’ psychiatric symptoms by enhancing treatment adherence. We aimed to systematically review the trial evidence of the effectiveness of AT on improving clinical outcomes in these patients. Method Systematic review and meta-analysis of published RCTs. We included studies testing AT as an adjunct intervention against treatment as usual or a comparator intervention in the general adult psychiatric population. The primary outcome of interest was improvement in psychiatric symptoms. Results We included six studies testing AT in schizophrenia spectrum disorders published since 2006. A meta-analysis showed AT significantly reduced psychiatric symptoms compared to usual treatment over a follow-up period of less than 1 year. We found no significant effects of AT on patients’ adherence and adherence attitudes. Conclusions AT is an effective adjunctive treatment for people with schizophrenia spectrum disorders

    Tailoring Selective Laser Melting Process Parameters for NiTi Implants

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    Complex-shaped NiTi constructions become more and more essential for biomedical applications especially for dental or cranio-maxillofacial implants. The additive manufacturing method of selective laser melting allows realizing complex-shaped elements with predefined porosity and three-dimensional micro-architecture directly out of the design data. We demonstrate that the intentional modification of the applied energy during the SLM-process allows tailoring the transformation temperatures of NiTi entities within the entire construction. Differential scanning calorimetry, x-ray diffraction, and metallographic analysis were employed for the thermal and structural characterizations. In particular, the phase transformation temperatures, the related crystallographic phases, and the formed microstructures of SLM constructions were determined for a series of SLM-processing parameters. The SLM-NiTi exhibits pseudoelastic behavior. In this manner, the properties of NiTi implants can be tailored to build smart implants with pre-defined micro-architecture and advanced performanc

    Options for accounting carbon sequestration in German forests

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    <p>Abstract</p> <p>Background</p> <p>The Accra climate change talks held from 21–27 August 2008 in Accra, Ghana, were part of an ongoing series of meetings leading up to the Copenhagen meeting in December 2009. During the meeting a set of options for accounting carbon sequestration in forestry on a post-2012 framework was presented. The options include gross-net and net-net accounting and approaches for establishing baselines.</p> <p>Results</p> <p>This article demonstrates the embedded consequences of Accra Accounting Options for the case study of German national GHG accounting. It presents the most current assessment of sequestration rates by forest management for the period 1990 – 2007, provides an outlook of future emissions and removals (up to the year 2042) as related to three different management scenarios, and shows that implementation of some Accra options may reverse sources to sinks, or sinks to sources.</p> <p>Conclusion</p> <p>The results of the study highlight the importance of elaborating an accounting system that would prioritize the climate convention goals, not national preferences.</p

    The management of acute knee dislocations: A global survey of orthopaedic surgeons' strategies.

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    PURPOSE: Great variety and controversies surround the management strategies of acute multiligament knee injuries (aMKLIs) and no established guidelines exist for resource-limited practices. The aim of this study was to compare the management approach of acute knee dislocations (AKDs) by orthopedic surgeons from nations with different economic status. METHODS: This descriptive cross-sectional scenario-based survey compares different management strategies for aMLKIs of surgeons in developed economic nations (DEN) and emerging markets and developing nations (EMDN). The main areas of focus were operative versus non-operative management, timing and staging of surgery, graft choice and vascular assessment strategies. The members of the Societe Internationale de Chirurgie Orthopedique et de Traumatologie (SICOT) were approached to participate and information was collected regarding their demographics, experience, hospital setting and management strategies of aMLKIs. These were analyzed after categorizing participants into DEN and EMDN based on the gross domestic product (GDP) per capita. RESULTS: One-hundred and thirty-eight orthopedic surgeons from 47 countries participated in this study, 67 from DEN and 71 (51.4%) from EMDN. DEN surgeons had more years of experience and were older (p < 0.05). Surgeons from EMDN mostly worked in public sector hospitals, were general orthopedic surgeons and treated patients from a low-income background. They preferred conservative management and delayed reconstruction with autograft (p < 0.05) if surgery was necessary. Surgeons from DEN favored early, single stage arthroscopic ligament reconstruction. Selective Computerized Tomography Angiography (CTA) was the most preferred choice of arterial examination for both groups. Significantly more EMDN surgeons preferred clinical examination (p < 0.05) and duplex doppler scanning (p < 0.05) compared to DEN surgeons. More surgeons from EMDN did not have access to a physiotherapist for their patients. CONCLUSIONS: Treatment of aMLKIs vary significantly based on the economic status of the country. Surgeons from DEN prefer early, single stage arthroscopic ligament reconstruction, while conservative management is favored in EMDN. Ligament surgery in EMDN is often delayed and staged. EMDN respondents utilize duplex doppler scanning and clinical examination more readily in their vascular assessment of aMLKIs. These findings highlight very distinct approaches to MLKIs in low-resource settings which are often neglected when guidelines are generated

    Damping of Selective-Laser-Melted NiTi for Medical Implants

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    NiTi exhibits distinct damping properties associated with the martensite-austenite transformation. We fabricated net-shape NiTi parts layer-by-layer using a laser beam that locally melted the NiTi powder. The damping properties of such NiTi parts were analyzed by the decay of cantilever vibrations in comparison to conventionally prepared NiTi. The dynamic modulus as a function of the temperature was derived from the resonant frequency. We found that the two cantilevers showed a damping ratio of about 0.03 at temperatures below austenite start, maximal values of up to 0.04 in the transformation regions and low values of about 0.005 above austenite finish. The results indicate that selective-laser-melted NiTi qualifies for the fabrication of shock-absorbing medical implants in the same manner than conventionally produced NiTi

    Stage Specific Glaucomatous Changes of the Macula recorded using Spectral Domain Optical Coherence Tomography.

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    BACKGROUND This study aimed to compare the thickness of different macular retinal layers in glaucomatous eyes and healthy controls, and evaluate the diagnostic performance of spectral domain optical coherence tomography (SD-OCT) parameters. METHODS In this cross-sectional comparative study, 48 glaucomatous eyes and 44 healthy controls were included. The thickness of the total retina and all retinal layers were obtained using the Early Treatment Diagnostic Retinopathy Study (ETDRS) grid. The minimal and average values of outer and inner ETDRS-rings were calculated. The diagnostic performance for detection of glaucoma was evaluated using the area under the receiver operating characteristic curve (AUC). RESULTS The thickness of the total retina, ganglion cell layer (GCL), and inner-plexiform layer (IPL) was significantly thinner in glaucomatous eyes in all sectors except the center (all p<0.05). The thickness of retinal nerve fiber layer (RNFL) was significantly thinner in the glaucoma group except in the center, nasal inner, and temporal outer sectors (all p<0.05). Layer thinning advanced with glaucoma severity. The minimal outer GCL thickness showed the highest AUC value for discrimination between glaucomatous eyes and healthy controls(0.955). The minimal outer IPL showed the highest AUC value for discriminating early-stage glaucomatous eyes from healthy controls (0.938). CONCLUSIONS Glaucomatous eyes were found to have significant thinning in the macular region. GCL and IPL showed high ability to discriminate glaucomatous and early-stage glaucomatous eyes from controls. Applying the minimal value to the ETDRS grid has the potential to provide good diagnostic abilities in glaucoma screening

    Assistive technology design and development for acceptable robotics companions for ageing years

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    © 2013 Farshid Amirabdollahian et al., licensee Versita Sp. z o. o. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivs license, which means that the text may be used for non-commercial purposes, provided credit is given to the author.A new stream of research and development responds to changes in life expectancy across the world. It includes technologies which enhance well-being of individuals, specifically for older people. The ACCOMPANY project focuses on home companion technologies and issues surrounding technology development for assistive purposes. The project responds to some overlooked aspects of technology design, divided into multiple areas such as empathic and social human-robot interaction, robot learning and memory visualisation, and monitoring persons’ activities at home. To bring these aspects together, a dedicated task is identified to ensure technological integration of these multiple approaches on an existing robotic platform, Care-O-Bot®3 in the context of a smart-home environment utilising a multitude of sensor arrays. Formative and summative evaluation cycles are then used to assess the emerging prototype towards identifying acceptable behaviours and roles for the robot, for example role as a butler or a trainer, while also comparing user requirements to achieved progress. In a novel approach, the project considers ethical concerns and by highlighting principles such as autonomy, independence, enablement, safety and privacy, it embarks on providing a discussion medium where user views on these principles and the existing tension between some of these principles, for example tension between privacy and autonomy over safety, can be captured and considered in design cycles and throughout project developmentsPeer reviewe

    Attosecond control of electrons emitted from a nanoscale metal tip

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    Attosecond science is based on steering of electrons with the electric field of well-controlled femtosecond laser pulses. It has led to, for example, the generation of XUV light pulses with a duration in the sub-100-attosecond regime, to the measurement of intra-molecular dynamics by diffraction of an electron taken from the molecule under scrutiny, and to novel ultrafast electron holography. All these effects have been observed with atoms or molecules in the gas phase. Although predicted to occur, a strong light-phase sensitivity of electrons liberated by few-cycle laser pulses from solids has hitherto been elusive. Here we show a carrier-envelope (C-E) phase-dependent current modulation of up to 100% recorded in spectra of electrons laser-emitted from a nanometric tungsten tip. Controlled by the C-E phase, electrons originate from either one or two sub-500as long instances within the 6-fs laser pulse, leading to the presence or absence of spectral interference. We also show that coherent elastic re-scattering of liberated electrons takes place at the metal surface. Due to field enhancement at the tip, a simple laser oscillator suffices to reach the required peak electric field strengths, allowing attosecond science experiments to be performed at the 100-Megahertz repetition rate level and rendering complex amplified laser systems dispensable. Practically, this work represents a simple, exquisitely sensitive C-E phase sensor device, which can be shrunk in volume down to ~ 1cm3. The results indicate that the above-mentioned novel attosecond science techniques developed with and for atoms and molecules can also be employed with solids. In particular, we foresee sub-femtosecond (sub-) nanometre probing of (collective) electron dynamics, such as plasmon polaritons, in solid-state systems ranging in size from mesoscopic solids via clusters to single protruding atoms.Comment: Final manuscript version submitted to Natur
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