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Critical thinking is one of the most important sets of cognitive abilities and dispositions required for both scientists and global citizens. In this explorative study, we examine which critical thinking aspects are perceived as relevant by biology graduate students and in what ways they found these aspects important for their scientific work. Data was collected from two cohorts of students participating in an online academic course focusing on the foundations of critical thinking. The course included weekly sessions in which different critical thinking topics were presented and discussed, followed by a seminar, in which individual students presented, reflected on, and received feedback on their biology research projects. Based on students' responses and artefacts collected during the course, several critical thinking aspects were identified as most relevant for students' scientific work, such as confirmation bias, methodological issues, and socio-cultural influences. Students also mentioned the value of open communication with peers when engaging in critical thinking. It is suggested that biology graduate students should have opportunities to learn about and engage with relevant aspects of critical thinking and to collaboratively reflect on their research using these aspects. [ABSTRACT FROM AUTHOR]

Lesson planning is a core part of teachers' professional competence. Written lesson plans play a significant role in science teacher education as a preparation for demonstration lessons during the final teacher certification exam. However, the few existing scoring rubrics on lesson plans are not particularly theoretically sound and are barely tested for the validity of score interpretations. In response to the demand for transparent and applicable criteria, we developed the rubric to assess science lesson plans (RALP) to assess science teachers' lesson plan quality. We employed a mixed‐methods approach: First, we present multiple sources of validity evidence (based on test content, internal structure, relations to other variables, and consequences of testing) as mainly quantitative indicators for the quality of the RALP. Based upon that, we applied the RALP to lesson plans written by preservice and trainee science teachers (N = 100) and provided a qualitative analysis of six cases to illustrate common patterns in these lesson plans. Results indicate that teacher educators consider the RALP criteria (N = 24) relevant and objectively applicable. Correlation analyses of the scores and two teacher educators' holistic quality assessment of all lesson plans provide convincing evidence that the RALP can discriminate lesson plan quality levels. Moreover, comparisons between preservice science teachers and trainee science teachers reveal that trainee teachers score significantly higher than preservice teachers, indicating that the RALP is sensitive to differences in teaching and planning experience. The application and in‐depth analysis of three criteria of the RALP illustrate these differences in levels of planning quality. We discuss possible applications of the RALP in science teacher education and research in science teaching. [ABSTRACT FROM AUTHOR]

Although much research exists of students' alternative conceptions about evolution and natural selection, the way in which these vary in time and how scientific explanations change during instruction remains to be described and understood. Therefore, the main objective of this research is to characterise the nature of the change in student thinking about evolution through the mechanism of natural selection during a six-lesson intervention with a group of ninth-grade students (14–15 years old) from a private subsidised school in Chile. The study group included thirteen students to whom a pre- and post-test was applied using the questionnaire Assessment of Contextual Reasoning about Natural Selection (ACORNS), and from whom short tasks were collected at the end of three lessons. The data were analysed using a quantitative and qualitative analysis of nine students grouped in five cases of study. The main patterns described here are the recurrence of the design teleology thinking in students, the initial use of key concepts such as mutation, survival, and differential reproduction during the trajectories, the abundance of mixed thinking during and at the end of the instruction, and the low coherence in the structure of thinking, both in time and through the different contexts analysed. [ABSTRACT FROM AUTHOR]

Background:As one part of scientific meta-knowledge, students’ meta-modelling knowledge should be promoted on different educational levels such as primary school, secondary school and university. This study focuses on the assessment of university students’ meta-modelling knowledge using a paper–pencil questionnaire. Purpose:The general purpose of this study was to assess and to describe university students’ meta-modelling knowledge. More specifically, it was analysed to what extent the meta-modelling knowledge, as expressed in a questionnaire, depends on the scientific discipline to which university students relate their answer and the concrete model to which they refer while answering. Sample:N = 184 students from one German university voluntarily participated in this study. Design and methods:The questionnaire was developed based on a theoretical framework for model competence and includes constructed response items asking about the purpose of models, ways for testing models and reasons for changing models. Students written answers were first analysed qualitatively based on the theoretical framework to decide whether they expressed advanced understandings or not. Further analyses then were conducted quantitatively. Results:Findings suggest that only few university students possess an advanced meta-modelling knowledge. However, significant more students who relate their answers to the STEM-disciplines expressed advanced understandings than those who referred to social sciences or linguistics/philology. Furthermore, university students who expressed an advanced meta-modelling knowledge referred to rather abstract kinds of models in order to explain their view. Conclusions:The present study supports the assumption that meta-modelling knowledge may be situated and contextualised. Both the scientific discipline and the concrete model to which university students refer seem to be relevant item features influencing university students’ expressed meta-modelling knowledge. Implications for assessment and teaching are discussed in the article. [ABSTRACT FROM AUTHOR]

This study investigated biology teachers’ (N = 148) understanding of models and modelling (MoMo), their model-related teaching activities and relations between the two. A framework which distinguishes five aspects of MoMo in science (nature of models,multiple models,purpose of models,testing modelsandchanging models) served as a theoretical background. Teachers’ understanding of MoMo was assessed using constructed-response items which were analysed qualitatively based on a coding scheme. The biology teachers mainly expressed a limited understanding of models as copies or idealised depictions used to show or to explain something. Model-related teaching activities were assessed through rating-scale items. The findings propose that models are primarily generated in biology lessons to show or to explain something but are rarely contrasted with other models, evaluated and modified. Significant correlations between teachers’ understanding of the aspecttesting modelsand their intensity of model-related teaching activities were found. This suggests that the aspecttesting modelsis a key aspect of promoting teaching activities related to MoMo in biology lessons. The findings are discussed with respect to relevant literature about MoMo in science education and educational implications are provided. [ABSTRACT FROM PUBLISHER]

Freshly cut beech deadwood was enriched in the canopy and on the ground in three cultural landscapes in Germany (Swabian Alb, Hainich-Dün, Schorfheide-Chorin) in order to analyse the diversity, distribution and interaction of wood-inhabiting fungi and beetles. After two years of wood decay 83 MOTUs (Molecular Operational Taxonomic Units) from 28 wood samples were identified. Flight Interception Traps (FITs) installed adjacent to the deadwood enrichments captured 29.465 beetles which were sorted to 566 species. Geographical ‘region’ was the main factor determining both beetle and fungal assemblages. The proportions of species occurring in all regions were low. Statistic models suggest that assemblages of both taxa differed between stratum and management praxis but their strength varied among regions. Fungal assemblages in Hainich-Dün, for which the data was most comprehensive, discriminated unmanaged from extensively managed and age-class forests (even-aged timber management) while canopy communities differed not from those near the ground. In contrast, the beetle assemblages at the same sites showed the opposite pattern. We pursued an approach in the search for fungus-beetle associations by computing cross correlations and visualize significant links in a network graph. These correlations can be used to formulate hypotheses on mutualistic relationships for example in respect to beetles acting as vectors of fungal spores. [ABSTRACT FROM AUTHOR]

The ribosomal DNA comprised of the ITS1-5.8S-ITS2 regions is widely used as a fungal marker in molecular ecology and systematics but cannot be aligned with confidence across genetically distant taxa. In order to study the diversity of Agaricomycotina in forest soils, we designed primers targeting the more alignable 28S (LSU) gene, which should be more useful for phylogenetic analyses of the detected taxa. This paper compares the performance of the established ITS1F/4B primer pair, which targets basidiomycetes, to that of two new pairs. Key factors in the comparison were the diversity covered, off-target amplification, rarefaction at different Operational Taxonomic Unit (OTU) cutoff levels, sensitivity of the method used to process the alignment to missing data and insecure positional homology, and the congruence of monophyletic clades with OTU assignments and BLAST-derived OTU names. The ITS primer pair yielded no off-target amplification but also exhibited the least fidelity to the expected phylogenetic groups. The LSU primers give complementary pictures of diversity, but were more sensitive to modifications of the alignment such as the removal of difficult-to align stretches. The LSU primers also yielded greater numbers of singletons but also had a greater tendency to produce OTUs containing sequences from a wider variety of species as judged by BLAST similarity. We introduced some new parameters to describe alignment heterogeneity based on Shannon entropy and the extent and contents of the OTUs in a phylogenetic tree space. Our results suggest that ITS should not be used when calculating phylogenetic trees from genetically distant sequences obtained from environmental DNA extractions and that it is inadvisable to define OTUs on the basis of very heterogeneous alignments. [ABSTRACT FROM AUTHOR]

Interactions between mushrooms, yeasts, and parasitic fungi are probably common in nature, but are rarely described. Bolete fruiting bodies are associated with a broad spectrum of microorganisms including yeasts, and they are commonly infected with filamentous mycoparasites of the genus Sepedonium (teleomorph Hypomyces). We report the isolation of 17 yeast strains from Paxillus and Xerocomus, 16 of which were obtained from the surface tissue, the primary site of Sepedonium infection. Phylogenetic analyses with the D1/D2 region of the 28S ribosomal gene and the internal transcribed spacers placed the yeasts as Rhodotorula, Rhodosporidium, and Mastigobasidium from the Pucciniomycotina, Cryptococcus, Cystofilobasidium, Holtermanniella, and Trichosporon from the Agaricomycotina, and Kluyveromyces from the Saccharomycotina including the first isolation of Rhodotorula graminis from Europe. To investigate the influence of the yeast strains on the mycoparasite and the host fungus, in vitro assays were conducted with Sepedonium chrysospermum and Paxillus involutus. Both S. chrysospermum growth inhibitory and stimulating yeast strains were detected among the isolates. The number of S. chrysospermum inhibitory yeast strains increased and the number of S. chrysospermum stimulatory yeast strains decreased in the presence of P. involutus in co-cultures. Low nutrient levels in the culture medium also led to an increased number of S. chrysospermum inhibitory yeast strains and ten yeasts inhibited the mycoparasite in spatial separation by a crosswall. Six yeast strains inhibited P. involutus in dual culture, and the inhibitory P. involutus yeast interactions increased to nine in the presence of S. chrysospermum. Our results suggest that the bolete-associated yeasts influence the growth of the mycoparasitic fungus, which may affect the health of the fruiting bodies. [ABSTRACT FROM AUTHOR]

Abstract: Solar thermal parabolic trough collectors can be used to provide heat for desalination, cooling and electricity generation. The set-up and some intermediate results of a measurement campaign for the evaluation of a parabolic trough collector — the Solitem PTC1800 — are presented. Optical tests of the concentrator were used to determine the intercept factor, allowing to give recommendations for optical improvements. Thermal testing up to 200°C with pressurised water showed low radiative and convective losses. [Copyright &y& Elsevier]

Abstract: The secondary structure of the ITS2 rDNA transcript (pre-rRNA) could provide information for identifying homologous nucleotide characters useful for cladistic inference of relationships. Such structure data could become taxonomic characters. This work compares the effect of several modern nucleotide alignment strategies, including those making use of structure data, on phylogenetic inference. From both the phylogenetic analyses and comparative secondary structure, implications for taxonomy and evolution of puffball fungi are discussed. Lycoperdaceae remain insufficiently resolved with present taxon and data sampling. Neither alignment allows statistically robust phylogenetic hypotheses under any current optimality criterion. The secondary structure data at this time are best used as accessory taxonomic characters as their phylogenetic resolving power and confidence in validity is limited compared with underlying nucleotide characters. We introduce a preliminary nomenclature convention to describe secondary structure for defining consensus features. These consensus structures are illustrated for the clades /Calvatia, /Handkea–Echinatum, /Vascellum, /Morganella, and /Plumbea–Paludosa (Bovista). [Copyright &y& Elsevier]

The study presents the frequencies of students' conceptions of growth and cell division before and after one hour of instruction. The investigation supplements qualitative results by directing attention to those conceptions which might occur most frequently to students: teachers can then concentrate their preparation on practical requirements. A total of 120 students (9th grade) participated in the investigation using a questionnaire. Some 29 students out of this group were instructed and the lesson's effectiveness was examined. The most frequent conception of growth and cell division in open tasks was ‘division of cells’ followed by the scientific concept of ‘division and enlargement’. In closed tasks, ‘division and enlargement’ became the most prominent concept - if students were encouraged to think about this, it might represent a plausible explanation to them, although often it was not yet in their repertoire of concepts. When conceptions of division were examined, ‘becoming more’ and ‘separation’ appear far more frequently than ‘becoming small’. In the lesson students broke a bar of chocolate into pieces. They clearly recognised that division leads to more pieces but the whole does not increase in size or mass. The scientific concept of ‘division and enlargement’ was almost completely transferred into the students' consciousness. [ABSTRACT FROM AUTHOR]

The phylogenetic relationships among most metazoan phyla remain uncertain. We obtained large numbers of gene sequences from metazoans, including key understudied taxa. Despite the amount of data and breadth of taxa analyzed, relationships among most metazoan phyla remained unresolved. In contrast, the same genes robustly resolved phylogenetic relationships within a major clade of Fungi of approximately the same age as the Metazoa. The differences in resolution within the two kingdoms suggest that the early history of metazoans was a radiation compressed in time, a finding that is in agreement with paleontotogical inferences. Furthermore, simulation analyses as well as studies of other radiations in deep time indicate that, given adequate sequence data, the lack of resolution in phylogenetic trees is a signature of closely spaced series of cladogenetic events. [ABSTRACT FROM AUTHOR]

The development of metaknowledge about models (MKM) and metaknowledge about the modelling process (MKP) are important in pre-service science teachers (PSTs) education. MKM refers to knowledge about the model's entities and its purposes, while MKP refers to knowledge about the components and structure of the modelling process. Assessing MKM and MKP is crucial to foster this knowledge in PSTs' education. However, assessment instruments focus on MKM rather than MKP, and the connection between MKM and MKP had not been examined deeply. This study validates and applies a diagram task for assessing PSTs' MKP. For validation, ten experts were surveyed and think-aloud interviews were conducted with ten PSTs. The findings support valid interpretations of PSTs' MKP based on the diagram task. In the main study, the diagram task was administrated to 63 PSTs, along with an MKM questionnaire. PSTs' MKP ranged from simple conceptions of modelling as a linear process including few components to sophisticated conceptions of modelling as an iterative process including multiple components. Furthermore, it was found that knowledge about using models to predict a phenomenon is an aspect connecting sophisticated MKM and MKP, indicating that this aspect is crucial to foster both, PSTs MKM and MKP. [ABSTRACT FROM AUTHOR]

Applications of seismic measurements for the prediction of hazard zones are applied practice in many tunnel drives in rock mass today. Next to a large exploration range and accurate localisation of discontinuities, seismic data provide attributes for a comprehensive characterisation of the ground conditions. A good synchronisation of all technical components is required to obtain optimum data quality and quantity while the tunnel excavation is not obstructed thereby. Firstly, the signal source must feed as much energy as possible into the rock in a very short time. Secondly, continuity of the signal generation with constant quality and its precise timing by means of wireless data transmission also ensure a reliable measurement process. Artificial intelligence is used to determine the quality of the recorded data already in the tunnel and feedback is given to the user keeping the data quality high. From the tunnel site, recorded raw data can be transferred to a cloud, from where an authorised processor collects them, wherever in the world. An immediately started data processing delivers a result within an hour that includes a geological forecast of up to 150 m of heading, depending on the rock mass condition. In addition to data quality, the quality of the results is crucial. Therefore, techniques are currently under development using machine learning to correlate and analyse seismic attributes with geological properties. This should lead to a more objective evaluation of the geological forecast in the future. [ABSTRACT FROM AUTHOR]

The home-field advantage (HFA) hypothesis has been used intensively to study leaf litter decomposition in various ecosystems. However, the HFA in woody substrates is still unexplored. Here, we reanalyzed and integrated existing datasets on various groups of microorganisms collected from natural deadwood of two temperate trees, Fagus sylvatica and Picea abies, from forests in which one or other of these species dominates but where both are present. Our aims were (i) to test the HFA hypothesis on wood decomposition rates of these two temperate tree species, and (ii) to investigate if HFA hypothesis can be explained by diversity and community composition of bacteria and in detail N-fixing bacteria (as determined by molecular 16S rRNA and nifH gene amplification) and fungi (as determined by molecular ITS rRNA amplification and sporocarp surveys). Our results showed that wood decomposition rates were accelerated at "home" versus "away" by 38.19% ± 20.04% (mean ± SE). We detected strong changes in fungal richness (increase 36–50%) and community composition (RANOSIM = 0.52–0.60, P < 0.05) according to HFA hypothesis. The changes of fungi were much stronger than for total bacteria and nitrogen fixing for both at richness and community composition levels. In conclusion, our results support the HFA hypothesis in deadwood: decomposition rate is accelerated at home due to specialization of fungal communities produced by the plant community above them. Furthermore, the higher richness of fungal sporocarps and nitrogen-fixing bacteria (nifH) may stimulate or at least stabilize wood decomposition rates at "home" versus "away." [ABSTRACT FROM AUTHOR]

Next‐generation sequencing (NGS) has significantly increased knowledge of microbial communities and their distribution. However, it is still not common to apply NGS technology to microbial conservation. We sought to use NGS technologies to evaluate conservation strategies for wood‐inhabiting fungi. Evaluating a deadwood experiment 3 years after it was established, we specifically examined which tree species combinations promoted the highest richness of wood‐inhabiting fungi. Deadwood enrichment was an effective strategy and logs of 6 tree species, either those with the highest wood‐inhabiting fungal α and γ diversity or those with the highest β diversity, maintained >1,000 operational taxonomic units (OTUs) spread over a wide range of taxonomic groups. In comparison, a conservation strategy based only on the results of sporocarp surveys yielded 591 OTUs. This result highlights the need to use NGS approaches to inform microbial conservation strategies. We also determined that 5 tree species with the highest saproxylic beetle γ diversity simultaneously conserved wood‐inhabiting fungi. Apart from deadwood volume, we suggest data on deadwood quality and species also be included as indicators, especially for wood‐inhabiting fungal diversity, and incorporated quickly in forest assessment and monitoring systems in Central Europe. Article impact statement: Enrichment of the species diversity of deadwood is an effective strategy for wood‐inhabiting fungal conservation in temperate forests. [ABSTRACT FROM AUTHOR]

Highlights • Demonstration of stable operation of a DSG power plant. • DSG is functional even during highly fluctuating DNI. • Mass flow is divided equally into parallel loops in evaporator and superheater. • Big buffer capacity of steam drum and longer pipelines stabilise operation. • Valuable lessons on the improvement of control strategy for DSG were learned. Abstract TSE1 is the first solar thermal power plant operating in Southeast Asia. It was planned by Solarlite GmbH with support of Tiede- & Niemann GmbH, both German based. It is the first power plant with direct steam generation (DSG) concept and superheating in parabolic troughs. The solar field has a nominal power of 19 MW th driving a 5 MW el turbine by superheated steam at 30 bar and 330 °C. During 2010/2011 Solarlite built the solar field, while the later owner and operator Thai Solar Energy (TSE) from Bangkok built the power block, in Kanchanaburi, Thailand. TSE1 is being operated by TSE since January 2012 (Krüger et al., 2012). This publication is based on a study within the KanDis project, funded by the German Federal Ministry for Economic Affairs and Energy, in which an extensive database of records of almost 500 sensors installed in the power plant (solar field and power block) has been investigated. The data have been provided by Solarlite with a time resolution of about 1 min. Within the KanDis project, a stable operation could be demonstrated (Khenissi et al., 2015; Krüger et al., 2016). Even under the fluctuating irradiance conditions in the rainy season of Thailand, the turbine could be operated well and generate electricity. Evaluation of the operation data has helped to learn more about DSG behaviour. The TSE1 layout and the implemented control strategies were evaluated and strategies for improvement of TSE1 are suggested within this paper. From the experiences with the TSE1 power plant, conclusions could be drawn to improve the layout and control of future DSG plants. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic nanoparticles (NPs) MnFe2O4 and Fe3O4 were stabilised by depositing an Al(OH)3 layer via a hydrolysis process. The particles displayed excellent colloidal stability in water and a high affinity to [18F]-fluoride and bisphosphonate groups. A high radiolabeling efficiency, 97% for 18F-fluoride and 100% for 64Cu-bisphosphonate conjugate, was achieved by simply incubating NPs with radioactivity solution at room temperature for 5 min. The properties of particles were strongly dependant on the thickness and hardness of the Al(OH)3 layer which could in turn be controlled by the hydrolysis method. The application of these Al(OH)3 coated magnetic NPs in molecular imaging has been further explored. The results demonstrated that these NPs are potential candidates as dual modal probes for MR and PET. In vivo PET imaging showed a slow release of 18F from NPs, but no sign of efflux of 64Cu. [Copyright &y& Elsevier]

Research in the field of students’ understandings of models and their use in science describes different frameworks concerning these understandings. Currently, there is no conjoint framework that combines these structures and so far, no investigation has focused on whether it reflects students' understandings sufficiently (empirical evaluation). Therefore, the purpose of this article is to present the results of an empirical evaluation of a conjoint theoretical framework. The theoretical framework integrates relevant research findings and comprises five aspects which are subdivided into three levels each:nature of models,multiple models,purpose of models,testing, and changing models. The study was conducted with a sample of 1,177 seventh to tenth graders (aged 11–19 years) using open-ended items. The data were analysed by identifying students' understandings of models (nature of models and multiple models) and their use in science (purpose of models,testing, and changing models), and comparing as well as assigning them to the content of the theoretical framework. A comprehensive category system of students' understandings was thus developed. Regarding the empirical evaluation, the students' understandings of the nature and the purpose of models were sufficiently described by the theoretical framework. Concerning the understandings of multiple, testing, and changing models, additional initial understandings (only one model possible, no testing of models, and no change of models) need to be considered. This conjoint and now empirically tested framework for students' understandings can provide a common basis for future science education research. Furthermore, evidence-based indications can be provided for teachers and their instructional practice. [ABSTRACT FROM PUBLISHER]

Scientific reasoning competencies are relevant science competencies and therefore the development of assessment instruments for scientific reasoning competencies has become an integral part of science education research. However, some authors have questioned the validity of the instruments available so far, since their psychometric quality has not been evaluated satisfactorily. In this study, an established German multiple-choice instrument to assess scientific reasoning competencies has been translated into English and Spanish and the translated versions were evaluated based on the translation, review, adjudication, pretesting and documentation (TRAPD) approach. Based on samples of German (N = 497), Australian (N = 103), and Chilean (N = 135) pre-service science teachers, statistical analyses (e.g. dimensionality and DIF analyses) provide psychometric evidence for test equivalence between the German and the translated versions of the instrument. Known groups comparisons provide evidence for the valid interpretation of the test scores as measures of scientific reasoning competencies. It is discussed that further studies might evaluate additional sources of validity evidence for the translated versions of the instrument, particularly focusing on cultural specificities. Independent of this need for further research, it is suggested that the three versions can be used to assess the scientific reasoning competencies of pre-service science teachers whose first language is English, German, or Spanish. [ABSTRACT FROM AUTHOR]

The value of renewable energy systems is undeniable since they rely on a free source that will not run out. However, they depend on meteorological conditions, leading to uncertainty on the instantaneous energy supply. An interesting concept consists on the strategic combination. In this article, two 1-MWel concentrated solar power/biomass hybrid power plants are presented and evaluated. One is intended for power generation only, while the other delivers combined heat and power. Technical and economic performances were evaluated through numerical simulation and calculation of the levelized cost of electricity. [ABSTRACT FROM AUTHOR]

Summary: Nitrogen deposition can strongly affect biodiversity, but its specific effects on terrestrial microbial communities and their roles for ecosystem functions and processes are still unclear. Here, we investigated the impacts of N deposition on wood‐inhabiting fungi (WIF) and their related ecological functions and processes in a highly N‐limited deadwood habitat. Based on high‐throughput sequencing, enzymatic activity assay and measurements of wood decomposition rates, we show that N addition has no significant effect on the overall WIF community composition or on related ecosystem functions and processes in this habitat. Nevertheless, we detected several switches in presence/absence (gain/loss) of wood‐inhabiting fungal OTUs due to the effect of N addition. The responses of WIF differed from previous studies carried out with fungi living in soil and leaf‐litter, which represent less N‐limited fungal habitats. Our results suggest that adaptation at different levels of organization and functional redundancy may explain this buffered response and the resistant microbial‐mediated ecosystem function and processes against N deposition in highly N‐limited habitats. [ABSTRACT FROM AUTHOR]

Students’ and pre-service teachers’ conceptions of scientists have been assessed in a variety of studies. One of the most commonly used instruments is the Draw-A-Scientist Test (DAST) which offers the advantage that no verbal skills are needed by the participants. In some studies, methodical challenges related to the DAST have been discussed; for example, the lack of drawing abilities among the subjects or the impact of the prompt itself on the drawings which lead to invalid interpretations. This study aims to evaluate the eligibility of the DAST or similar instruments to validly assess conceptions of scientists and their work. Pre-service science teachers in two cohorts (N1 = 79,N2 = 101) were prompted to draw their conceptions of a scientist, the location at which the scientist is working, and his/her scientific activity. The participants of cohort 2 were also asked to give written descriptions of their drawings and information on the conditions while they were drawing. From the results, several points of methodical criticism can be made which question the valid interpretation of DAST-drawings. Instead of using the DAST, we suggest developing and evaluating other formats, such as open-ended or closed-ended instruments which could produce a more validly interpretable assessment of individuals’ conceptions in this field. [ABSTRACT FROM PUBLISHER]

Microorganisms play a crucial role in the biological decomposition of plant litter in terrestrial ecosystems. Due to the permanently changing litter quality during decomposition, studies of both fungi and bacteria at a fine taxonomic resolution are required during the whole process. Here we investigated microbial community succession in decomposing leaf litter of temperate beech forest using pyrotag sequencing of the bacterial 16S and the fungal internal transcribed spacer ( ITS) rRNA genes. Our results reveal that both communities underwent rapid changes. Proteobacteria, Actinobacteria and Bacteroidetes dominated over the entire study period, but their taxonomic composition and abundances changed markedly among sampling dates. The fungal community also changed dynamically as decomposition progressed, with ascomycete fungi being increasingly replaced by basidiomycetes. We found a consistent and highly significant correlation between bacterial richness and fungal richness ( R = 0.76, P < 0.001) and community structure ( RMantel = 0.85, P < 0.001), providing evidence of coupled dynamics in the fungal and bacterial communities. A network analysis highlighted nonrandom co-occurrences among bacterial and fungal taxa as well as a shift in the cross-kingdom co-occurrence pattern of their communities from the early to the later stages of decomposition. During this process, macronutrients, micronutrients, C:N ratio and pH were significantly correlated with the fungal and bacterial communities, while bacterial richness positively correlated with three hydrolytic enzymes important for C, N and P acquisition. Overall, we provide evidence that the complex litter decay is the result of a dynamic cross-kingdom functional succession. [ABSTRACT FROM AUTHOR]

The aim of this study was to improve the criterion-related test score interpretation of a text-based assessment of scientific reasoning competencies in higher education by evaluating factors which systematically affect item difficulty. To provide evidence about the specific demands which test items of various difficulty make on pre-service teachers’ scientific reasoning competencies, we applied a general linear mixed model which allows estimation of the impact of item features on the response observations. The item features had been identified during a standard setting process. Results indicate important predictive potential of one formal item feature (length of response options), two features based on cognitive demands (processing data from tables, processing abstract concepts) and one feature based on solid knowledge (specialist terms). The revealed predictive potential of item features was in accordance with the cognitive demands operationalised in our competence model. Thus, we conclude that the findings support the validity of our interpretation of the test scores as measures of scientific reasoning competencies. [ABSTRACT FROM PUBLISHER]

Fungi are prominent drivers of ecological processes in soils, so that fungal communities across different soil ecosystems have been well investigated. However, for arable soils taxonomically resolved fine-scale studies including vertical itemization of fungal communities are still missing. Here, we combined a cloning/Sanger sequencing approach of the ITS/LSU region as marker for general fungi and of the partial SSU region for arbuscular mycorrhizal fungi (AMF) to characterize the microbiome in different maize soil habitats. Four compartments were analyzed over two annual cycles 2009 and 2010: a) ploughed soil in 0–10 cm, b) rooted soil in 40–50 cm, c) root-free soil in 60–70 cm soil depth and d) maize roots. Ascomycota was the most dominant phylum across all compartments. Fungal communities including yeasts and AMF differed strongly between compartments. Inter alia, Tetracladium, the overall largest MOTU (molecular operational taxonomic unit), occurred in all compartments, whereas Trichosporon dominated all soil compartments. Sequences belonging to unclassified Helotiales were forming the most abundant MOTUs exclusively present in roots. This study gives new insights on spatial distribution of fungi and helps to link fungal communities to specific ecological properties such as varying resources, which characterize particular niches of the heterogeneous soil environment. [ABSTRACT FROM AUTHOR]

Lignin and its degradation, particularly in forest ecosystems, play a major role in the global carbon cycle. Filamentous fungi equipped with extracellular oxidoreductases (oxidative enzymes), i.e., laccase, manganese-dependent peroxidases and several other peroxidases, are the key players in the bioconversion of lignin. In particular, for coarse woody debris (CWD), this process is poorly understood and the activities of laccase and peroxidases have never been studied on a large field scale. We investigated the activities of these enzymes in 701 samples of Fagus sylvatica, Picea abies and Pinus sylvestris CWD across three regions in Germany and analyzed their dependence on pH, water content, wood density, total lignin, organic extractives, metals, water-soluble lignin fragments and fungal species richness. Respective enzyme activities were present in 79 % of all samples, and the activities were highly variable and more frequent in F. sylvatica than in coniferous wood. Logistic regressions and correlations between enzyme activities and the variables revealed that the fungal community structure and the amount of water-soluble lignin fragments are most important determinants, and that the prevalent acidic pH in CWD is suitable to facilitate laccase and manganese peroxidase activities. Concentrations of metals (manganese, copper, iron) were sufficient to ensure synthesis and functioning of relevant enzymes. Based on this large field study, we conclude that laccase and peroxidases in CWD are highly relevant for lignin degradation, but the variable pattern of their secretion is the result of a complex array of wood parameters and the fungal community structure, which could only partly be resolved. [ABSTRACT FROM AUTHOR]

Background:An elaborated understanding of Nature of Science (NOS) is seen as an important part of scientific literacy. In order to enable teachers to adequately discuss NOS in their lessons, various approaches have recently been employed to improve teachers’ understanding of NOS. Purpose:This study investigated the effect of participating in a newly developedScience, Technology, Engineering and Mathematics(STEM) curriculum at the Freie Universität Berlin (Germany) on pre-service teachers’ NOS views. Program description:In the new STEM curriculum, two versions of explicitly teaching NOS, which are discussed in the literature, have been adopted: the pre-service teachers explicitly reflect upon nature and history of science (version one) as well as conduct own scientific investigations (version two). Sample:N = 76 pre-service teachers from different semester levels (cross-sectional study) who participated in the new STEM curriculum took part in this study (intervention group). As control groups, students who did not partake in the new curriculum participated (pre-service primary (N = 134), science (N = 198), and no-science (N = 161) teachers). Design and methods:In order to allow an economic assessment, a testing instrument with closed-item formats was developed to assess the respondents’ views about six NOS aspects. Results:The intervention group shows significantly more elaborated NOS views than a relevant control group (p < .01,g = .48). Additionally, a one-way ANOVA reveals a positive effect of semester level on NOS views for the intervention group (p < .01; η² = .16) but not for the control groups. Conclusion:The findings support evidence suggesting that explicit approaches are effective when fostering an informed understanding of NOS. More specifically, a sequence of both versions of explicitly teaching NOS discussed in the literature seems to be a way to successfully promote pre-service teachers’ NOS understanding. [ABSTRACT FROM PUBLISHER]

Soil fungi play an essential role in the decomposition of plant-derived organic material entering soils. The quality and quantity of organic compounds vary seasonally as well as with soil depth. To elucidate how these resources affect fungal communities in an arable soil, a field experiment was set up with two plant species, maize and wheat. Resource availability was experimentally manipulated by maize litter input on one half of these maize and wheat plots after harvest in autumn. Fungal biomass was determined by ergosterol quantification, and community structure was investigated by fungal automated ribosomal intergenic spacer analysis (F-ARISA). An annual cycle was assessed across a depth gradient, distinguishing three soil habitats: the plough layer, rooted soil below the plough layer, and deeper root-free soil. Fungal communities appeared highly dynamic and varied according to soil depth and plant resources. In the plough layer, the availability of litter played a dominant role in shaping fungal communities, whereas in the rooted layer below, community structure and biomass mainly differed between plant species. This plant effect was also extended into the root-free soil at a depth of 70 cm. In winter, the availability of litter also affected fungal communities in deeper soil layers, suggesting vertical transport processes under fallow conditions. These distinct resource effects indicate diverse ecological niches along the soil profile, comprising specific fungal metacommunities. The recorded responses to both living plants and litter point to a central role of fungi in connecting primary production and decomposition within the plant-soil system. [ABSTRACT FROM AUTHOR]

Decaying wood hosts a large diversity of seldom investigated protists. Environmental sequencing offers novel insights into communities, but has rarely been applied to saproxylic protists. We investigated the diversity of bright-spored wood-inhabiting Myxomycetes by environmental sequencing. Myxomycetes have a complex life cycle culminating in the formation of mainly macroscopic fruiting bodies, highly variable in shape and colour that are often found on decaying logs. Our hypothesis was that diversity of bright-spored Myxomycetes would increase with decay. DNA was extracted from wood chips collected from 17 beech logs of varying decay stages from the Hainich-Dün region in Central Germany. We obtained 260 partial small subunit ribosomal RNA gene sequences of bright-spored Myxomycetes that were assembled into 29 OTUs, of which 65% were less than 98% similar to those in the existing database. The OTU richness revealed by molecular analysis surpassed that of a parallel inventory of fruiting bodies. We tested several environmental variables and identified pH, rather than decay stage, as the main structuring factor of myxomycete distribution. [ABSTRACT FROM AUTHOR]

Forest management practices (FMPs) significantly influence important ecological processes and services in Central European forests, such as leaf litter decomposition and nutrient cycling. Changes in leaf litter diversity, and thus, its quality as well as microbial community structure and function induced by different FMPs were hypothesized to be the main drivers causing shifts in decomposition rates and nutrient release in managed forests. In a litterbag experiment lasting 473 days, we aimed to investigate the effects of FMPs (even-aged timber management, selective logging and unmanaged) on bacterial and fungal communities involved in leaf litter degradation over time. Our results showed that microbial communities in leaf litter were strongly influenced by both FMPs and sampling date. The results from nonmetric multidimensional scaling (NMDS) ordination revealed distinct patterns of bacterial and fungal successions over time in leaf litter. We demonstrated that FMPs and sampling dates can influence a range of factors, including leaf litter quality, microbial macronutrients, and pH, which significantly correlate with microbial community successions. [ABSTRACT FROM AUTHOR]

Due to the high diversity of bacteria in many ecosystems, their slow generation times, specific but mostly unknown nutrient requirements and syntrophic interactions, isolation based approaches in microbial ecology mostly fail to describe microbial community structure. Thus, cultivation independent techniques, which rely on directly extracted nucleic acids from the environment, are a well-used alternative. For example, bacterial automated ribosomal intergenic spacer analysis (B-ARISA) is one of the widely used methods for fingerprinting bacterial communities after PCR-based amplification of selected regions of the operon coding for rRNA genes using community DNA. However, B-ARISA alone does not provide any taxonomic information and the results may be severely biased in relation to the primer set selection. Furthermore, amplified DNA stemming from mitochondrial or chloroplast templates might strongly bias the obtained fingerprints. In this study, we determined the applicability of three different B-ARISA primer sets to the study of bacterial communities. The results from in silico analysis harnessing publicly available sequence databases showed that all three primer sets tested are specific to bacteria but only two primers sets assure high bacterial taxa coverage (1406f/23Sr and ITSF/ITSReub). Considering the study of bacteria in a plant interface, the primer set ITSF/ITSReub was found to amplify (in silico) sequences of some important crop species such as Sorghum bicolor and Zea mays. Bacterial genera and plant species potentially amplified by different primer sets are given. These data were confirmed when DNA extracted from soil and plant samples were analyzed. The presented information could be useful when interpreting existing B-ARISA results and planning B-ARISA experiments, especially when plant DNA can be expected. [ABSTRACT FROM AUTHOR]

The widespread paradigm in ecology that community structure determines function has recently been challenged by the high complexity of microbial communities. Here, we investigate the patterns of and connections between microbial community structure and microbially-mediated ecological function across different forest management practices and temporal changes in leaf litter across beech forest ecosystems in Central Europe. Our results clearly indicate distinct pattern of microbial community structure in response to forest management and time. However, those patterns were not reflected when potential enzymatic activities of microbes were measured. We postulate that in our forest ecosystems, a disconnect between microbial community structure and function may be present due to differences between the drivers of microbial growth and those of microbial function. [ABSTRACT FROM AUTHOR]

The impact of changes within a single land-use category or land-use intensity on microbial communities is poorly understood, especially with respect to fungi. Here we assessed how forest management regimes and a change in forest type affect the richness and community structure of wood-inhabiting fungi across Germany. We used molecular methods based on the length polymorphism of the internal transcribed spacers and the 5.8S rRNA gene to assess fungal operational taxonomic units (OTUs). A cloning/sequencing approach was used to identify taxonomic affinities of the fungal OTUs. Overall, 20–24% and 25–27% of native fungal OTUs from forest reserves and semi-natural forests became undetectable or were lost in managed and converted forests, respectively. Fungal richness was significantly reduced during a regeneration phase in age-class beech forests with a high level of wood extraction (P = 0.017), whereas fungal community structures were not significantly affected. Conversion of forests from native, deciduous to coniferous species caused significant changes in the fungal community structure (R = 0.64–0.66, P = 0.0001) and could reduce fungal richness (P < 0.05) which may depend on which coniferous species was introduced. Our results showed that Ascocoryne cylichnium, Armillaria sp., Exophiala moniliae, Hyphodontia subalutacea and Fomes fomentarius, all known for wood-decaying abilities were strongly reduced in their abundances when forests were converted from beech to coniferous. We conclude that changes within a single land-use category can be regarded as a major threat to fungal diversity in temperate forest ecosystems. [Copyright &y& Elsevier]

Fungal secretory peroxidases mediate fundamental ecological functions in the conversion and degradation of plant biomass. Many of these enzymes have strong oxidizing activities towards aromatic compounds and are involved in the degradation of plant cell wall (lignin) and humus. They comprise three major groups: class II peroxidases (including lignin peroxidase, manganese peroxidase, versatile peroxidase and generic peroxidase), dye-decolorizing peroxidases, and heme-thiolate peroxidases (e.g. unspecific/aromatic peroxygenase, chloroperoxidase). Here, we have repeatedly observed a widespread expression of all major peroxidase groups in leaf and needle litter across a range of forest ecosystems (e.g. Fagus, Picea, Acer, Quercus, and Populus spp.), which are widespread in Europe and North America. Manganese peroxidases and unspecific peroxygenases were found expressed in all nine investigated forest sites, and dye-decolorizing peroxidases were observed in five of the nine sites, thereby indicating biological significance of these enzymes for fungal physiology and ecosystem processes. Transcripts of selected secretory peroxidase genes were also analyzed in pure cultures of several litter-decomposing species and other fungi. Using this information, we were able to match, in environmental litter samples, two manganese peroxidase sequences to Mycena galopus and Mycena epipterygia and one unspecific peroxygenase transcript to Mycena galopus, suggesting an important role of this litter- and coarse woody debris-dwelling genus in the disintegration and transformation of litter aromatics and organic matter formation. [ABSTRACT FROM AUTHOR]

Leaf litter decomposition is the key ecological process that determines the sustainability of managed forest ecosystems, however very few studies hitherto have investigated this process with respect to silvicultural management practices. The aims of the present study were to investigate the effects of forest management practices on leaf litter decomposition rates, nutrient dynamics (C, N, Mg, K, Ca, P) and the activity of ligninolytic enzymes. We approached these questions using a 473 day long litterbag experiment. We found that age-class beech and spruce forests (high forest management intensity) had significantly higher decomposition rates and nutrient release (most nutrients) than unmanaged deciduous forest reserves (P<0.05). The site with near-to-nature forest management (low forest management intensity) exhibited no significant differences in litter decomposition rate, C release, lignin decomposition, and C/N, lignin/N and ligninolytic enzyme patterns compared to the unmanaged deciduous forest reserves, but most nutrient dynamics examined in this study were significantly faster under such near-to-nature forest management practices. Analyzing the activities of ligninolytic enzymes provided evidence that different forest system management practices affect litter decomposition by changing microbial enzyme activities, at least over the investigated time frame of 473 days (laccase, P<0.0001; manganese peroxidase (MnP), P = 0.0260). Our results also indicate that lignin decomposition is the rate limiting step in leaf litter decomposition and that MnP is one of the key oxidative enzymes of litter degradation. We demonstrate here that forest system management practices can significantly affect important ecological processes and services such as decomposition and nutrient cycling. [ABSTRACT FROM AUTHOR]

Nitrogen availability in dead wood is highly restricted and associations with N-fixing bacteria are thought to enable wood-decaying fungi to meet their nitrogen requirements for vegetative and generative growth. We assessed the diversity of nifH (dinitrogenase reductase) genes in dead wood of the common temperate tree species Fagus sylvatica and Picea abies from differently managed forest plots in Germany using molecular tools. By incorporating these genes into a large compilation of published nifH sequences and subsequent phylogenetic analyses of deduced proteins we verified the presence of diverse pools corresponding to functional nifH, almost all of which are new to science. The distribution of nifH genes strongly correlated with tree species and decay class, but not with forest management, while higher fungal fructification was correlated with decreasing nitrogen content of the dead wood and positively correlated with nifH diversity, especially during the intermediate stage of wood decay. Network analyses based on non-random species co-occurrence patterns revealed interactions among fungi and N-fixing bacteria in the dead wood and strongly indicate the occurrence of at least commensal relationships between these taxa. [ABSTRACT FROM AUTHOR]

Abstract: Soil food webs are important determinants for the carbon flow through terrestrial systems, with the trophic networks between microbes and microfaunal grazers forming the basis for processing plant resources. At an agricultural field site cropped with maize or wheat, plant carbon input to soil was experimentally manipulated by amendment with maize litter. The community structure of dominant micro-food web components, the bacteria, fungi, protozoa and nematodes, was investigated across a depth gradient comprising plough layer, rooted soil below plough horizon, and deeper root free soil. The community composition and diversity within micro-food webs, and the response to resource supply, were assessed in summer, the vegetation period with highest root exudation. In the plough layer amendment with plant residues increased microbial biomass as well as density of fan shaped amoeba morphotypes and of bacterial- and fungal-feeding nematodes. Diversity of food web assemblages was assessed by operational taxonomic units (OTU) for bacteria and fungi, protozoa morphotypes and nematode families. Changes in diversity were either not apparent (fungi, protozoa), negatively related to litter (bacteria) or positively linked to the presence of a specific crop plant (bacteria, nematodes). Based on nematode functional guilds and the related enrichment and structure index, general food web conditions were assigned as nutrient enriched, with a high degree of disturbance, and a dominance of the bacterial energy channel. In sum, litter amendment fostered the abundance but not the diversity of organisms as food webs remained bottom heavy with only small amounts of carbon conserved at higher trophic levels. Food web structure was more affected by the abiotic (soil profile) and biotic (crop plant) environment than by the supply with litter resources. [Copyright &y& Elsevier]