Varying effects of subgoal labeled expository text in programming,chemistry, and statistics

Originally intended as a replication study, this study discusses differences in problem solving performance among different domains caused by the same instructional intervention. The learning sciences acknowledges similarities in the learners’ cognitive architecture that allow interventions to apply across domains, but it also argues that each domain has characteristics that might affect how interventions impact learning. The present study uses an instructional design technique that had previously improved learners’ problem solving performance in programming: subgoal labeled expository text and subgoal labeled worked examples. It intended to replicate this effect for solving problems in statistics and chemistry. However, each of the experiments in the three domains had a different pattern of results for problem solving performance. While the subgoal labeled worked example consistently improved performance, the subgoal labeled expository text, which interacted with subgoal labeled worked examples in programming, had an additive effect with subgoal labeled worked examples in chemistry and no effect in statistics. Differences in patterns of results are believed to be due to complexity of the content to be learned, especially in terms of mapping problem solving procedures to solving problems, and the familiarity of tools used to solve problems in the domain. Subgoal labeled expository text was effective only when students learned more complex content and used unfamiliar problem solving tools.     

Biological Principles and Threshold Concepts for Understanding Natural Selection

Modern evolutionary theory is both a central theory and an integrative framework of the life sciences. This is reflected in the common references to evolution in modern science education curricula and contexts. In fact, evolution is a core idea that is supposed to support biology learning by facilitating the organization of relevant knowledge. In addition, evolution can function as a pivotal link between concepts and highlight similarities in the complexity of biological concepts. However, empirical studies in many countries have for decades identified deficiencies in students’ scientific understanding of evolution mainly focusing on natural selection. Clearly, there are major obstacles to learning natural selection, and we argue that to overcome them, it is essential to address explicitly the general abstract concepts that underlie the biological processes, e.g., randomness or probability. Hence, we propose a two-dimensional framework for analyzing and structuring teaching of natural selection. The first—purely biological—dimension embraces the three main principles variation, heredity, and selection structured in nine key concepts that form the core idea of natural selection. The second dimension encompasses four so-called thresholds, i.e., general abstract and/or non-perceptual concepts: randomness, probability, spatial scales, and temporal scales. We claim that both of these dimensions must be continuously considered, in tandem, when teaching evolution in order to allow development of a meaningful understanding of the process. Further, we suggest that making the thresholds tangible with the aid of appropriate kinds of visualizations will facilitate grasping of the threshold concepts, and thus, help learners to overcome the difficulties in understanding the central theory of life.     

Evaluation of Jigsaw,a cooperative learning technique

Cooperative learning techniques have been promoted for the development of academic and social competencies. One such technique, Jigsaw, creates cooperation by structuring student interdependence through the learning task, rather than through the grading system. A process and outcome evaluation of Jigsaw was conducted. Eleven teachers of fifth-grade classes received Jigsaw in-service training and conducted Jigsaw in their classes over a school year. Students in 13 other fifth-grade classes served as a comparison group. Students received a pretest and a post-test assessing attitudes toward self, peers, and school, and achievement and attendance records were collected. The process evaluation revealed that the quality and frequency of Jigsaw implementation varied greatly. Jigsaw failed to have a positive effect on the outcome variables, even for the five classes where it was implemented proficiently. The results, which are consistent with an earlier study (J. Moskowitz, J. Malvin, G. Schaeffer, & E. Schaps, 1983, American Education Research Journal, 20, 687–696), are discussed in terms of a theoretical shortcoming of this technique.     

Globalisierung im Hochschulwesen — ein Abschied von etablierten Werten der Internationalisierung?

Gibt es Anzeichen dafür, dass der Trend zum grenzübergreifenden Angebot von Hochschulbildung und zur Gründung hochschulischer Au?enstellen im Ausland die auf gegenseitigem Verst?ndnis und Vertrauen beruhende internationale Hochschulkooperation obsolet macht und sie durch einen internationalen Hochschulwettbewerb ersetzt? Diese Frage wird aus empirisch-deskriptiver Perspektive behandelt. Die Autoren verstehen Globalisierung nicht als eine notwendigerweise mit einem bestimmten Wertesystem verknüpfte kausale Kraft hinter jüngeren Entwicklungstrends, sondern als ein zun?chst lediglich beschreibendes Konzept, dessen Diskussion die sorgf?ltige Analyse der ihm zugrunde liegenden empirischen Prozesse voraussetzt. Unter dieser Grundannahme werten sie erste vorliegende Studien zur Struktur und Ausbreitung der Transnational Education aus und erg?nzen sie um eine Analyse aktueller Entwicklungen hinsichtlich Studienimport und-export in Deutschland. Zudem werden überblicksartig die Implikationen des internationalen Dienstleistungsabkommens GATS für das Hochschulwesen er?rtert. Auf diese Weise kann eine Reihe von Bezügen zwischen etablierten Werten der Internationalisierung und globalisierungstypischen Ph?nomenen im Hochschulwesen ausgemacht werden.     

Evaluation of the appropriate time period between sampling and analyzing for automated urinalysis

Introduction

Preanalytical specifications for urinalysis must be strictly adhered to avoid false interpretations. Aim of the present study is to examine whether the preanalytical factor ‘time point of analysis’ significantly influences stability of urine samples for urine particle and dipstick analysis.

Materials and methods

In 321 pathological spontaneous urine samples, urine dipstick (Urisys™2400, Combur-10-Test™strips, Roche Diagnostics, Mannheim, Germany) and particle analysis (UF-1000 i™, Sysmex, Norderstedt, Germany) were performed within 90 min, 120 min and 240 min after urine collection.

Results

For urine particle analysis, a significant increase in conductivity (120 vs. 90 min: P < 0.001, 240 vs. 90 min: P < 0.001) and a significant decrease in WBC (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), RBC (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), casts (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001) and epithelial cells (120 vs. 90 min P = 0.610, 240 vs. 90 min P = 0.041) were found. There were no significant changes for bacteria. Regarding urine dipstick analysis, misclassification rates between measurements were significant for pH (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), leukocytes (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), nitrite (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), protein (120 vs. 90 min P < 0.001, 240 vs. 90 min P<0.001), ketone (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), blood (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), specific gravity (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001) and urobilinogen (120 vs. 90 min, P = 0.031). Misclassification rates were not significant for glucose and bilirubin.

Conclusion

Most parameters critically depend on the time window between sampling and analysis. Our study stresses the importance of adherence to early time points in urinalysis (within 90 min).Key words: urinalysis, automation, analytical sample preparation methods, flow cytometry, specimen handling     

In Infants' Hands: Identification of Preverbal Infants at Risk for Primary Language Delay

Early identification of primary language delay is crucial to implement effective prevention programs. Available screening instruments are based on parents' reports and have only insufficient predictive validity. This study employed observational measures of preverbal infants' gestural communication to test its predictive validity for identifying later language delays. Pointing behavior of fifty‐nine 12‐month‐old infants was analyzed and related to their language skills 1 year later. Results confirm predictive validity of preverbal communication for language skills with the hand shape of pointing being superior compared to the underlying motives for pointing (imperative vs. declarative). Twelve‐month‐olds who pointed only with their open hand but never with their index finger were at risk for primary language delay at 2 years of age.     

Word length and word frequency affect eye movements in dyslexic children reading in a regular (German) orthography

We combined independently the word length and word frequency to examine if the difficulty of reading material affects eye movements in readers of German, which has high orthographic regularity, comparing the outcome with previous findings available in other languages. Sixteen carefully selected German-speaking dyslexic children (mean age, 9.5 years) and 16 age-matched controls read aloud four lists, each comprising ten unrelated words. The lists varied orthogonally in word length and word frequency: high-frequency, short; high-frequency, long; low-frequency, short; low-frequency, long. Eye movements were measured using a scanning laser ophthalmoscope (SLO). In dyslexic children, fixation durations and the number of saccades increased both with word length and word frequency. The percentage of regressions was only increased for low-frequency words. Most of these effects were qualitatively similar in the two groups, but stronger in dyslexic children, pointing to a deficient higher-level word processing, especially phonological deficit. The results indicate that reading eye movements in German children are modulated by the degree of difficulty, and orthographic regularity of the language can determine the nature of modulation. The findings suggest that, similar to Italian but unlike English readers, German children prefer indirect sub-lexical strategy of grapheme-phoneme conversion.     

Modellierung von Lehrerkompetenzen

This contribution will investigate both the subject-specific and the didactic competencies of trainee teachers for lower secondary education in mathematics on the basis of the study “Mathematics Teaching in the 21st Century (MT21)”, which compares criteria-based samples from Germany, Bulgaria, South Korea, Taiwan, Mexico and the USA. In order to analyze their strengths and weaknesses more precisely, the paper considers both traditional IRT-scaling of competencies, which involves a simple loading of test performance in mathematics and didactics of mathematics, and an alternative. Under the assumption that solving items concerning didactics of mathematics requires competencies in didactics of mathematics and mathematics itself, a double-barreled approach was used in the alternative. In a further elaboration of this model, knowledge of arithmetic, algebra, functions, geometry and stochastic was used as a set of further explanatory factors for solving the items. This third model, which presumes a hierarchical structure of teaching competencies, displays the best data fit. Only this model reflects the specialisms and focal points of the education and training systems in the countries participating in MT21 concerning the relative learning opportunities in mathematics and didactics of mathematics and concerning the five subject areas in the field of mathematics.