122 research outputs found
Measuring media literacy: The Development of the Medienprofis-Test in Switzerland
Trotz intensiver theoretischer Diskussionen über den Begriff Medienkompetenz liegen bis anhin kaum empirisch validierte Messinstrumente zur empirischen Erfassung dieser Kompetenzen bei Kindern und Jugendlichen vor. Die bestehenden Angebote lassen sich in drei Typen gliedern: 1) Kommerzielle Prüfungen im Kontext von Weiterbildungsangeboten, 2) wissenschaftliche Tests im Kontext empirischer Studien sowie 3) spielerische Tests und Quizzes im Kontext von Sensibilisierungskampagnen. Ausgewählte Angebote werden vorgestellt und in Bezug auf ihre Brauchbarkeit für praktische Medienarbeit diskutiert. Als Ergänzung und Erweiterung des bestehenden Angebots wird der schweizerische Medienprofis-Test vorgestellt. Dabei handelt es sich um einen spielerischen Test, der frei zugänglich und empirisch validiert ist. Der Test umfasst fünf Themenbereiche: 1. Digitalisierung und Computerisierung, 2. Informationsfreiheit und Glaubwürdigkeit, 3. Sex, Gewalt und Jugendschutz, 4. Neue Geschäftsmodelle und Kommerz sowie 5. Personalisierung und Datenschutz. Die abgefragten Kompetenzen orientieren sich darüber hinaus am Modullehrplan «Medien & Informatik» des neuen deutschschweizerischen Lehrplans 21. Die von Experten validierten Items wurden anhand einer Stichprobe von Schülerinnen und Schülern der 3. bis 8. Klassen erprobt und mittels Raschmodell skaliert. Lehrpersonen können den Test im Klassenverband durchführen und erhalten dabei neben aggregierten Ergebnissen auch Empfehlungen für passende Unterrichtsmaterialien. Der Medienprofis-Test ist ein erster Schritt, ein standardisiertes und validiertes Messinstrument zur Verfügung zu stellen und die Diskussion um die Ausprägungen der Medienkompetenz mit empirisch Daten zu bereichern.Despite intensive theoretical discussions regarding the concept of media literacy, so far no empirically validated measuring instruments have been developed to determine this competence among children and adolescents. Existing offers can be categorized into three types: 1) commercial tests in the context of further education and training, 2) scientific tests in the context of empirical studies, and 3) playful tests and quizzes in the context of awareness campaigns. We present selected products and discuss them with reference to their suitability for practical media work. The Swiss Medienprofis-Test is introduced as an addition and extension to existing products. This is a playful test, which is freely available and empirically validated. It encompasses five subject areas: 1. digitalization and computerisation, 2. freedom of information and credibility, 3. sex, violence and youth protection, 4. new business models and commerce and 5. personalisation and privacy protection. The tested literacies are structured parallel to the school subject ‹media & computer science› from the new Swiss-German curriculum, Lehrplan 21. The test items which were validated by experts, were tested using a random sample of students from 3rd to 8th grade and were scaled according to the Rasch model. Teachers can conduct the test in school classes and receive aggregated feedback as well as suggestions for suitable teaching materials. The Medienprofis-Test is a first step towards providing a standardized and validated measuring instrument and enhancing the discussion regarding the definition of media literacy with empirical data
Light dosimetry in photodynamic therapy using optical fiber delivery
This paper considers rapid calculations of light distributions in a tissue for photodynamic therapy. The delivery system considered is a single optical fiber, although other configurations are easily modeled. The influence of optical heterogeneities in the tissue is considered. The optical distributions surrounding an optical fiber within a tissue can be well approximated by a point source of light placed one 'reduced mean free path' (MFP) in front of the fiber tip. One MFP equals 1/(µ_a + µ_s(1-g)). Then the simple diffusion theory expression for 3D diffusion from a point source predicts the light distribution in the tissue. The influence of optical heterogeneities in the tissue can also be well approximated. A method is described for representing regions of increased absorption (such as a region with increased vascularity) as virtual sources of 'negative radiant power' such that linear superposition of the true primary source and the virtual sources yields the net light distribution in the heterogeneous tissue. The method is rapid, flexible, and generally accurate to within about 15% error. The method yields light distributions in optically complex issues
Light dosimetry in photodynamic therapy using optical fiber delivery
This paper considers rapid calculations of light distributions in a tissue for photodynamic therapy. The delivery system considered is a single optical fiber, although other configurations are easily modeled. The influence of optical heterogeneities in the tissue is considered. The optical distributions surrounding an optical fiber within a tissue can be well approximated by a point source of light placed one 'reduced mean free path' (MFP) in front of the fiber tip. One MFP equals 1/(µ_a + µ_s(1-g)). Then the simple diffusion theory expression for 3D diffusion from a point source predicts the light distribution in the tissue. The influence of optical heterogeneities in the tissue can also be well approximated. A method is described for representing regions of increased absorption (such as a region with increased vascularity) as virtual sources of 'negative radiant power' such that linear superposition of the true primary source and the virtual sources yields the net light distribution in the heterogeneous tissue. The method is rapid, flexible, and generally accurate to within about 15% error. The method yields light distributions in optically complex issues
a randomized, open, multicenter phase III trial of lenalidomide/dexamethasone versus lenalidomide/dexamethasone plus subsequent autologous stem cell transplantation and lenalidomide maintenance in patients with relapsed multiple myeloma
Background Despite novel therapeutic agents, most multiple myeloma (MM)
patients eventually relapse. Two large phase III trials have shown
significantly improved response rates (RR) of lenalidomide/dexamethasone
compared with placebo/dexamethasone in relapsed MM (RMM) patients. These
results have led to the approval of lenalidomide for RMM patients and
lenalidomide/dexamethasone has since become a widely accepted second-line
treatment. Furthermore, in RMM patients consolidation with high-dose
chemotherapy plus autologous stem cell transplantation has been shown to
significantly increase progression free survival (PFS) as compared to
cyclophosphamide in a phase III trial. The randomized prospective ReLApsE
trial is designed to evaluate PFS after lenalidomide/dexamethasone induction,
high-dose chemotherapy consolidation plus autologous stem cell transplantation
and lenalidomide maintenance compared with the well-established
lenalidomide/dexamethasone regimen in RMM patients. Methods/Design ReLApsE is
a randomized, open, multicenter phase III trial in a planned study population
of 282 RMM patients. All patients receive three lenalidomide/dexamethasone
cycles and - in absence of available stem cells from earlier harvesting -
undergo peripheral blood stem cell mobilization and harvesting. Subsequently,
patients in arm A continue on consecutive lenalidomide/dexamethasone cycles,
patients in arm B undergo high dose chemotherapy plus autologous stem cell
transplantation followed by lenalidomide maintenance until discontinuation
criteria are met. Therapeutic response is evaluated after the 3rd (arm A + B)
and the 5th lenalidomide/dexamethasone cycle (arm A) or 2 months after
autologous stem cell transplantation (arm B) and every 3 months thereafter
(arm A + B). After finishing the study treatment, patients are followed up for
survival and subsequent myeloma therapies. The expected trial duration is 6.25
years from first patient in to last patient out. The primary endpoint is PFS,
secondary endpoints include overall survival (OS), RR, time to best response
and the influence of early versus late salvage high dose chemotherapy plus
autologous stem cell transplantation on OS. Discussion This phase III trial is
designed to evaluate whether high dose chemotherapy plus autologous stem cell
transplantation and lenalidomide maintenance after lenalidomide/dexamethasone
induction improves PFS compared with the well-established continued
lenalidomide/dexamethasone regimen in RMM patients. Trial registration:
ISRCTN16345835 (date of registration 2010-08-24)
The Effect of Hot Deformation Parameters on Microstructure Evolution of the α-Phase in Ti-6Al-4V
The effect of high-temperature deformation and the influence of hot working parameters on microstructure evolution during isothermal hot forging of Ti-6Al-4V in the alpha phase field were investigated. A series of hot isothermal axis-symmetric compression tests were carried out at temperatures both low and high in the alpha stability field [(1153 K and 1223 K (880 °C and 950 °C), respectively], using three strain rates (0.01, 0.1 and 1.0/s) relevant to industrial press forging. The microstructures and orientation of the alpha laths were determined using optical microscopy and electron backscatter diffraction techniques. The experimental results show that there is a change in lath morphology of the secondary α phase under the influence of the deformation parameters, and that α lath thickness appears to have little influence on flow behavior
In-situ measurement of texture development rate in CaIrO₃ post-perovskite
The rate of crystallographic preferred orientation (CPO) development during deformation of post-perovskite is crucial in interpreting seismic anisotropy in the lowermost mantle but the stability field of MgSiO3 post-perovskite prevents high-strain deformation experiments being performed on it. Therefore, to constrain the rate of CPO development in post-perovskite, we deformed CaIrO3, a low-pressure analogue of MgSiO3 post-perovskite, in simple shear at 3.2GPa and 400○C to a shear strain (γ) of 0.81. From X-ray diffraction patterns acquired during deformation, we invert for CPO as a function of strain. By comparing the CPO that develops with visco-plastic self-consistent (VPSC) models we constrain the critical resolved shear stresses (CRSS) of the non-primary slip-systems in CaIrO3 to be of order 6 times stronger than the primary [100](010) slip system. This value is significantly less than has been assumed by previous studies and if applicable to MgSiO3 implies that seismic anisotropy in the D′ layer develops slower than has previously been assumed
Delineation of Two Clinically and Molecularly Distinct Subgroups of Posterior Fossa Ependymoma
Despite the histological similarity of ependymomas from throughout the neuroaxis, the disease likely comprises multiple independent entities, each with a distinct molecular pathogenesis. Transcriptional profiling of two large independent cohorts of ependymoma reveals the existence of two demographically, transcriptionally, genetically, and clinically distinct groups of posterior fossa (PF) ependymomas. Group A patients are younger, have laterally located tumors with a balanced genome, and are much more likely to exhibit recurrence, metastasis at recurrence, and death compared with Group B patients. Identification and optimization of immunohistochemical (IHC) markers for PF ependymoma subgroups allowed validation of our findings on a third independent cohort, using a human ependymoma tissue microarray, and provides a tool for prospective prognostication and stratification of PF ependymoma patients
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Super-enhancer-based identification of a BATF3/IL-2R-module reveals vulnerabilities in anaplastic large cell lymphoma.
Anaplastic large cell lymphoma (ALCL), an aggressive CD30-positive T-cell lymphoma, comprises systemic anaplastic lymphoma kinase (ALK)-positive, and ALK-negative, primary cutaneous and breast implant-associated ALCL. Prognosis of some ALCL subgroups is still unsatisfactory, and already in second line effective treatment options are lacking. To identify genes defining ALCL cell state and dependencies, we here characterize super-enhancer regions by genome-wide H3K27ac ChIP-seq. In addition to known ALCL key regulators, the AP-1-member BATF3 and IL-2 receptor (IL2R)-components are among the top hits. Specific and high-level IL2R expression in ALCL correlates with BATF3 expression. Confirming a regulatory link, IL-2R-expression decreases following BATF3 knockout, and BATF3 is recruited to IL2R regulatory regions. Functionally, IL-2, IL-15 and Neo-2/15, a hyper-stable IL-2/IL-15 mimic, accelerate ALCL growth and activate STAT1, STAT5 and ERK1/2. In line, strong IL-2Rα-expression in ALCL patients is linked to more aggressive clinical presentation. Finally, an IL-2Rα-targeting antibody-drug conjugate efficiently kills ALCL cells in vitro and in vivo. Our results highlight the importance of the BATF3/IL-2R-module for ALCL biology and identify IL-2Rα-targeting as a promising treatment strategy for ALCL
Rationale and design of the German-Speaking Myeloma Multicenter Group (GMMG) trial ReLApsE: a randomized, open, multicenter phase III trial of lenalidomide/dexamethasone versus lenalidomide/dexamethasone plus subsequent autologous stem cell transplantation and lenalidomide maintenance in patients with relapsed multiple myeloma
Therapeutic impact of cytoreductive surgery and irradiation of posterior fossa ependymoma in the molecular era: a retrospective multicohort analysis
PURPOSE: Posterior fossa ependymoma comprises two distinct molecular variants termed EPN_PFA and EPN_PFB that have a distinct biology and natural history. The therapeutic value of cytoreductive surgery and radiation therapy for posterior fossa ependymoma after accounting for molecular subgroup is not known. METHODS: Four independent nonoverlapping retrospective cohorts of posterior fossa ependymomas (n = 820) were profiled using genome-wide methylation arrays. Risk stratification models were designed based on known clinical and newly described molecular biomarkers identified by multivariable Cox proportional hazards analyses. RESULTS: Molecular subgroup is a powerful independent predictor of outcome even when accounting for age or treatment regimen. Incompletely resected EPN_PFA ependymomas have a dismal prognosis, with a 5-year progression-free survival ranging from 26.1% to 56.8% across all four cohorts. Although first-line (adjuvant) radiation is clearly beneficial for completely resected EPN_PFA, a substantial proportion of patients with EPN_PFB can be cured with surgery alone, and patients with relapsed EPN_PFB can often be treated successfully with delayed external-beam irradiation. CONCLUSION: The most impactful biomarker for posterior fossa ependymoma is molecular subgroup affiliation, independent of other demographic or treatment variables. However, both EPN_PFA and EPN_PFB still benefit from increased extent of resection, with the survival rates being particularly poor for subtotally resected EPN_PFA, even with adjuvant radiation therapy. Patients with EPN_PFB who undergo gross total resection are at lower risk for relapse and should be considered for inclusion in a randomized clinical trial of observation alone with radiation reserved for those who experience recurrence
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