Lehr-Lernprozesse im Physikunterricht - eine Videostudie

[Der Beitrag berichtet aus einem Projekt des DFG-Schwerpunktprogramms Bildungsqualität]. Hintergrund für dieses Projekt sind ... die Befunde aus internationalen Vergleichsstudien (TIMSS, PISA). Die Studie untersucht den deutschen Physikunterricht und die Lernprozesse, die in diesem Unterricht ermöglicht werden. Ziel ist es, eine erste Bestandsaufnahme der "didaktischen Orchestrierung" von Physikuntericht vorzunehmen und insbesondere die Möglichkeiten für verständnisvolles Lernen zu untersuchen ... . Mit theoriegeleiteten Analysen von Unterrichtsbeobachtungen und von ergänzenden Daten aus Befragungen und Tests soll geklärt werden, wie sich Bedingungen bzw. Muster des Physikunterrichts auf Lernprozesse und Bildungsergebnisse auswirken. Der Beitrag konzentriert sich auf die Zielorientierung und die Lernbegleitung. (DIPF/Orig.

Food safety metrics relevant to low- and middle-income countries

London School of Hygiene and Tropical MedicineRoyal Veterinary College, LondonWorld Health OrganizationFood and Agriculture Organization of the United Nation

Conception de prothèse surcorrigée pour arthroplastie totale de l’épaule

L’arthrose est une maladie se traduisant par une détérioration progressive du cartilage articulaire. Dans certains cas avancés, cette dégradation peut résulter en une destruction totale du cartilage, contraignant les os à frotter les uns contre les autres. Les personnes atteintes présentent des douleurs articulaires et leur mobilité peut être affectée [1]. Cette maladie peut toucher plusieurs articulations telles que les hanches, les genoux, les doigts ou les épaules. Les causes de l’arthrose de l’épaule sont multiples : instabilité chronique, fracture de l’humérus ou encore rupture de la coiffe des rotateurs. Il existe trois types d’arthrose de l’épaule. Le type A correspond à une érosion symétrique de la glène sans subluxation tandis que le type C désigne une dysplasie sans usure [2]. L’attention est portée ici sur le type B pour lequel l’usure du cartilage apparaît de manière asymétrique, le plus souvent postérieurement. Suivant le degré de détérioration des articulations, l’arthroplastie peut consister à retirer l’articulation malade sans poser de prothèse, sinon à remplacer une partie ou la totalité de l’articulation par une prothèse [3], comme dans le cas de ce projet. Néanmoins, l’arthroplastie totale de l’épaule chez des patients de type B présente des risques post-opératoires de subluxation gléno-humérale. L’implantation d’une prothèse asymétrique spécifique à la morphologie du patient peut être une solution à ce problème. En effet, grâce à la combinaison des images CT de la scapula de chaque patient, du logiciel CAD et d’analyse par éléments finis, il est possible de choisir une surcorrection de la prothèse permettant d’obtenir une répartition des efforts minimisant la subluxation. Ce projet de Bachelor se focalisera sur la conception de deux prothèses surcorrigées uniques, destinées à deux patients de type B, en veillant à obtenir une meilleure répartition des efforts au sein de la scapula et une subluxation plus faible

Students' Interest in Geoscience Topics, Contexts, and Methods

Geoscience topics are playing an increasingly important role with regard to the future of our planet. Consequently, they have been moving into the educational foreground because of their societal relevance. The question is, however: Are pupils interested in these topics? This is important didactically, for interest is both a prerequisite and a goal of any effective learning process. What are the topics and methods that will interest students and what are those that will not? What contexts are particularly suitable for introducing children and adolescents to geoscientific topics and methods? Do pupils show a private interest in geoscientific issues? A questionnaire was submitted to 333 German senior grammar school students aged between 17 and 19. The study generally shows a medium interest in geoscientific topics with students. The most interesting topics are those that are related to human beings or environmental threat, respectively, such as "earthquakes" or "climatic changes". The interest in a topic correlates with the context that it is related to. Young adults share a relatively high interest in the topics "individual", "society" as well as "social responsibility". Concerning special methods in class there is a particular tendency towards action-oriented working methods like the carrying out of geoscientific experiments. In their spare time youths seldom occupy with geoscientific subjects. This underlines the important role of school lessons in raising the student's interest in these fields. In german school geography covers geoscientific contents far more than biology, while chemistry and physics insufficiently deal with them

Food safety in Kenya: Focus on dairy

Infographic created for Voice for Change Partnership, Food and Nutrition Security Dissemination Forum: Evidence for Policy, Advocacy and Partnerships, Online Webinar, 8 July 2020

Multi-centre evaluation of the speed-oligo Mycobacteria assay for differentiation of Mycobacterium spp. in clinical isolates

<p>Abstract</p> <p>Background</p> <p>A new DNA line probe assay (Speed-oligo Mycobacteria, Vircell) has been launched for rapid differentiation of <it>Mycobacterium </it>spp. from cultures. Compared to other line-probe assays, Speed-oligo Mycobacteria covers a relatively limited spectrum of species but uses a simpler and faster dip-stick technique. The present multi-centre, multi-country study aimed at evaluating the utility and usability of Speed-oligo Mycobacteria in routine mycobacteriology diagnostics. Results from Speed-oligo Myobacteria were compared to those from Genotype CM (HAIN lifescience, Nehren, Germany), another line-probe assay.</p> <p>Methods</p> <p>Speed-oligo Mycobacteria assay was performed in three main steps: 1) DNA extraction from cultured material 2) PCR amplification of the target gene and an internal control and 3) hybridization of the PCR products to specific probes by means of a dip-stick.</p> <p>Results</p> <p>Two hundred forty-two clinical isolates were recovered from consecutive positive mycobacterial cultures at two German (IML Gauting, Bioscientia Ingelheim), one Czech (KLINLAB Prague), and at a Sudanese (Khartoum) laboratory. All <it>Mycobacterium </it>species covered by the assay were reliably recognized. The rate of false positive results was 1.2% and concerned only the species <it>M. marinum </it>and <it>M. peregrinum</it>. The identification rate, i.e. the proportion of isolates which was correctly differentiated to the level of species or complex by the assay, differed significantly among laboratories being 94.9%, 90.7%, and 75.0% at the study sites IML Gauting, KLINLAB Prague and Bioscientia Ingelheim, respectively. This difference was caused by different spectra of NTM species encountered by the laboratory centres in daily routine diagnostics.</p> <p>Conclusions</p> <p>Speed-oligo Mycobacteria assay was proved a rapid and easy-to-perform alternative to conventional line-probe assays. The assay showed excellent sensitivity with regard to identification of genus <it>Mycobacterium </it>and species/complexes covered by the test. However, due to its relatively limited spectrum of taxa, a varying proportion of NTM may not be identified by the assay in daily diagnostics demanding further analyses. The only significant shortcoming in terms of specificity was the misidentification of the clinically relevant species <it>M. marinum</it>.</p

Poly(I:C) Enhances the Susceptibility of Leukemic Cells to NK Cell Cytotoxicity and Phagocytosis by DC

α Active specific immunotherapy aims at stimulating the host's immune system to recognize and eradicate malignant cells. The concomitant activation of dendritic cells (DC) and natural killer (NK) cells is an attractive modality for immune-based therapies. Inducing immunogenic cell death to facilitate tumor cell recognition and phagocytosis by neighbouring immune cells is of utmost importance for guiding the outcome of the immune response. We previously reported that acute myeloid leukemic (AML) cells in response to electroporation with the synthetic dsRNA analogue poly(I:C) exert improved immunogenicity, demonstrated by enhanced DC-activating and NK cell interferon-γ-inducing capacities. To further invigorate the potential of these immunogenic tumor cells, we explored their effect on the phagocytic and cytotoxic capacity of DC and NK cells, respectively. Using single-cell analysis, we assessed these functionalities in two- and three-party cocultures. Following poly(I:C) electroporation AML cells become highly susceptible to NK cell-mediated killing and phagocytosis by DC. Moreover, the enhanced killing and the improved uptake are strongly correlated. Interestingly, tumor cell killing, but not phagocytosis, is further enhanced in three-party cocultures provided that these tumor cells were upfront electroporated with poly(I:C). Altogether, poly(I:C)-electroporated AML cells potently activate DC and NK cell functions and stimulate NK-DC cross-talk in terms of tumor cell killing. These data strongly support the use of poly(I:C) as a cancer vaccine component, providing a way to overcome immune evasion by leukemic cells

Physics instruction - based on girls\u27 and boys\u27 interests

Es wird über zwei aufeinander aufbauende Studien berichtet, die sich (1) mit der Erhebung der Interessen an Physik bzw. am Physikunterricht und (2) mit der im Rahmen eines BLK-Modellversuchs durchgeführten Umsetzung der Ergebnisse der ersten Studie im Physikanfangsunterrichts (7. Schuljahr) befassen. Es wird gezeigt, dass das aus der Interessenstudie abgeleitete Unterrichtskonzept Mädchen in ihrer kognitiven Entwicklung und in ihrem auf Physik bezogenen Interesse und Selbstvertrauen fördert, ohne die Jungen zu benachteiligen. (DIPF/Orig.)Results of two consecutive studies are reported concerning (1) the assessment of students interests in physics and in physics as a school subject, respectively, and (2) the effects of a physics curriculum for beginners (seventh grade) oriented at the results of the first study. It will be shown that the intervention has favorable effects (without negative side effects on the boys) on the cognitive development of girls, as well as on their interest and self concept concerning physics learning. (DIPF/Orig.