Általános iskolai és középiskolás diákok lemeztektonikai tévképzetei egy kvalitatív, keresztmetszeti vizsgálat tükrében

Misconception research adds important knowledge to the research of conceptual change, which is the key process of learning and instruction. The study of misconceptions enables the analysis of the conceptual networks of both individuals and groups, and makes it possible to follow their changes over time. There has been a great amount of international research concerning geographical misconceptions, but it has been underrepresented in Hungary so far. Therefore, we decided to start unearthing how Hungarian students think about certain geographical concepts and phenomena. In the first step, we aimed at identifying plate-tectonics-related misconceptions in the framework of a cross-sectional, comparative analysis of five age groups (Ntotal=470). Convenience sampling was carried out in six primary and five secondary schools in 2012 and 2013. Employing data and methods triangulation, we collected multiple kinds of data by administering a three-part diagnostic test to students. The present study aims at introducing the misconceptions we found by using comparative content analysis. Our results indicate that Hungarian students are mainly characterized by preconceptions at a younger age, and by conceptual misconceptions at an older age. Vernacular misconceptions are present in a smaller proportion, while the proportions of cultural and popular misconceptions are insignificant. We argue that misconceptions should not be identified only as a problem, but also as an opportunity to help students develop a correct conceptual system in the course of teaching and learning. Furthermore, students should obtain transferable knowledge that can be used in their everyday life, their future work, and in other professional or scientific fields. However, if conceptual change does not happen, misconceptions may persist, or even intensify, and, as a result, they may later hinder meaningful learning and the development of proper critical thinking

Derivation of a Qualitative Model for the Spatial Characteristic Wavelength of Extrusion Flow Instabilities: Investigation of a Polybutadiene Rubber through Capillary, Slit and Complex Geometry Extrusion Dies

The extrusion flow instabilities of commercial polybutadiene (PBD) are investigated as a function of the different extrusion die geometries, such as round capillary, slit, and complex cross-section profile slit dies via capillary rheology. Qualitative models are used to fit the experimental data for the spatial characteristic wavelength (λ) of the appearing extrusion flow instabilities. A new qualitative model for the slit die geometry, rectangular cross-section, is derived based on the theoretical concept of the “two layers” extrudate and the force balance at the die exit region. The proposed qualitative model for the slit die geometry is used to predict the spatial characteristic wavelength (λ) for extrudates obtained by complex cross-section profile slit die geometries similar to industrial manufacturing. Correlation between the ratio of the extensional (Y$_s$) and shear (σ$_x$) stress at the die exit area and the characteristic dimension, height H for slit dies and diameter D for round capillary dies, is presented. Moreover, a geometry-dependent model is used to predict the spatial characteristic wavelength (λ) of the extrusion flow instabilities from a round capillary die to a slit die and vice versa

Mechano-Optical Characterization of Extrusion Flow Instabilities in Styrene-Butadiene Rubbers: Investigating the Influence of Molecular Properties and Die Geometry

The extrusion flow instabilities of two commercial styrene‐butadiene rubbers are investigated as they vary in isomer content (1,4‐cis, 1,4‐trans, and 1,2 conformation) of the butadiene monomer and the molecular architecture (linear, branched). The investigated samples have similar multimodal molecular weight distribution. Two geometries of extrusion dies, slit and round capillary, are compared in terms of the type and the spatial characteristics of the flow instabilities. The latter are quantified using three methods: a highly pressure sensitive slit die, online and offline optical analysis. The highly pressure‐sensitive slit die has three piezoelectric pressure transducers (Δt ≈ 10$^{-3}$ s and Δp ≈ 10$^{-5}$ bar) placed along the die length. The characteristic frequency (f$_{Char.}$) of the flow instabilities follows a power law behavior as a function of shear rate to a 0.5 power for both materials,  $_{ℎ.}$∝$^{˙0.5}$$_{app.}$. A qualitative model is used to predict the spatial characteristic wavelength (λ) of the flow instabilities from round capillary to slit dies and vice versa. Slip velocities (V$_{s}$) are used to quantify the slippage at slit and round capillary dies as well

Hogyan látjuk Európát? Egy berlini középiskola diákjainak mentális térképei Európáról és annak határairól

Nowadays, the experience related to migration is leading to a series of social and economic debates about the borders of nation states, and this is leaving a noticeable imprint on students' thinking even in formal education. Students may have very different experiences regarding borders in Hungary, but even more so in a super-diverse urban environment like Berlin. Despite this, research into students' knowledge about European borders is relatively scarce. This study explores Berlin secondary school students' perceptions of Europe. Using the method of mental mapping, we investigated how Berlin secondary school students (n=45) perceive Europe and its borders. The results indicate that students' spatial and cartographic knowledge of Europe is rather limited. Furthermore, it appears that students predominantly interpret Europe as groups of nation states, resulting in a predominance of representations of the borders of nation states in their maps. Drawing on the diagnostic significance of mental maps, the study presents thought-provoking results on students' spatial cognition, spatial orientation and map skills

A Streptococcus pneumoniae (pneumococcus) -infekciók ezer arca

Absztrakt A Streptococcus pneumoniae (pneumococcus) által okozott infekciók világszerte, így Magyarországon is, tartósan magas morbiditási és mortalitási mutatókkal rendelkeznek a gyermek- és felnőttpopulációban egyaránt. A felnőttkori, hospitalizációt igénylő, otthon szerzett tüdőgyulladások 35–40%-ában a pneumococcus kóroki szerepe igazolható, az S. pneumoniae-pneumoniák 25–30%-a bacteraemiával jár. Az összes fertőzés 5–7%-a fatális kimenetelű, idősek és rizikóbetegek körében az arány meredeken növekedik. A súlyos, invazív formában zajló infekciók esetében a mortalitás elérheti a 20%-ot, a szövődményráta adekvát antibiotikus terápia mellett is jelentős. A szerzők összefoglalják a pneumococcalis betegségek epidemiológiáját, a noninvazív és invazív fertőzések patogenezisét, valamint prezentálják a legfontosabb klinikai aspektusokat esetbemutatásokon keresztül. A betegek rizikóstratifikációja, a hemokultúrák vétele és a korai antibiotikum-kezelés mellett az aktív immunizáció széles körű alkalmazása segíthet csökkenteni az invazív fertőzések mortalitását. A pneumococcus elleni vakcináció javasolt minden 50 év feletti felnőttnek, illetve minden 18 év feletti krónikus betegnek, aki alapbetegsége miatt fogékony a pneumococcalis infekcióra. Orv. Hetil., 2015, 156(44), 1769–1777

A Novel Pathway Regulates Thyroid Hormone Availability in Rat and Human Hypothalamic Neurosecretory Neurons

Hypothalamic neurosecretory systems are fundamental regulatory circuits influenced by thyroid hormone. Monocarboxylate-transporter-8 (MCT8)-mediated uptake of thyroid hormone followed by type 3 deiodinase (D3)-catalyzed inactivation represent limiting regulatory factors of neuronal T3 availability. In the present study we addressed the localization and subcellular distribution of D3 and MCT8 in neurosecretory neurons and addressed D3 function in their axons. Intense D3-immunoreactivity was observed in axon varicosities in the external zone of the rat median eminence and the neurohaemal zone of the human infundibulum containing axon terminals of hypophysiotropic parvocellular neurons. Immuno-electronmicroscopy localized D3 to dense-core vesicles in hypophysiotropic axon varicosities. N-STORM-superresolution-microscopy detected the active center containing C-terminus of D3 at the outer surface of these organelles. Double-labeling immunofluorescent confocal microscopy revealed that D3 is present in the majority of GnRH, CRH and GHRH axons but only in a minority of TRH axons, while absent from somatostatin-containing neurons. Bimolecular-Fluorescence-Complementation identified D3 homodimers, a prerequisite for D3 activity, in processes of GT1-7 cells. Furthermore, T3-inducible D3 catalytic activity was detected in the rat median eminence. Triple-labeling immunofluorescence and immuno-electronmicroscopy revealed the presence of MCT8 on the surface of the vast majority of all types of hypophysiotropic terminals. The presence of MCT8 was also demonstrated on the axon terminals in the neurohaemal zone of the human infundibulum. The unexpected role of hypophysiotropic axons in fine-tuned regulation of T3 availability in these cells via MCT8-mediated transport and D3-catalyzed inactivation may represent a novel regulatory core mechanism for metabolism, growth, stress and reproduction in rodents and humans