Global maps of science can be used as a reference system to chart career trajectories, the location of emerging research frontiers, or the expertise profiles of institutes or nations. This paper ...details data preparation, analysis, and layout performed when designing and subsequently updating the UCSD map of science and classification system. The original classification and map use 7.2 million papers and their references from Elsevier's Scopus (about 15,000 source titles, 2001-2005) and Thomson Reuters' Web of Science (WoS) Science, Social Science, Arts & Humanities Citation Indexes (about 9,000 source titles, 2001-2004)-about 16,000 unique source titles. The updated map and classification adds six years (2005-2010) of WoS data and three years (2006-2008) from Scopus to the existing category structure-increasing the number of source titles to about 25,000. To our knowledge, this is the first time that a widely used map of science was updated. A comparison of the original 5-year and the new 10-year maps and classification system show (i) an increase in the total number of journals that can be mapped by 9,409 journals (social sciences had a 80% increase, humanities a 119% increase, medical (32%) and natural science (74%)), (ii) a simplification of the map by assigning all but five highly interdisciplinary journals to exactly one discipline, (iii) a more even distribution of journals over the 554 subdisciplines and 13 disciplines when calculating the coefficient of variation, and (iv) a better reflection of journal clusters when compared with paper-level citation data. When evaluating the map with a listing of desirable features for maps of science, the updated map is shown to have higher mapping accuracy, easier understandability as fewer journals are multiply classified, and higher usability for the generation of data overlays, among others.
In this paper, we introduce a new concept for constructing prior distributions. We exploit the natural nested structure inherent to many model components, which defines the model component to be a ...flexible extension of a base model. Proper priors are defined to penalise the complexity induced by deviating from the simpler base model and are formulated after the input of a user-defined scaling parameter for that model component, both in the univariate and the multivariate case. These priors are invariant to reparameterisations, have a natural connection to Jeffreys' priors, are designed to support Occam's razor and seem to have excellent robustness properties, all which are highly desirable and allow us to use this approach to define default prior distributions. Through examples and theoretical results, we demonstrate the appropriateness of this approach and how it can be applied in various situations.
Preservice teachers who are specialising in the teaching of the subject natural science at a primary school level, ought to demonstrate the ability to present lessons that provoke a joyful yet ...meaningful educational experience amongst learners. One such approach that was taken, was when natural science preservice teachers were tasked with developing educational science board games as a means to enrich their teaching practice during a recent school visitation opportunity. However, given this educational exercise, what remains a mystery from a teacher development perspective is whether this exercise provoked some form of ‘pedagogical thinking’ among preservice teachers? It is with this question in mind, that the study investigated whether the task of developing educational science board games sparked the ability of preservice teachers to demonstrate knowledge of pedagogical content. The study draws on a modified understanding of Shulman’s pedagogical content knowledge model, which in the context of gamification requires one to effectively transmit ‘subject knowledge’ in an interactive manner through ‘educational board game practices and engagement’. Using a focus group discussion and photo-voice methodology as data collection techniques, this qualitative study uncovered how preservice teachers demonstrated i) knowledge of the curriculum, ii) knowledge of instructional strategies, iii) knowledge of learner-thinking, and iv) knowledge of assessment. This study holds a series of implications for future research in the field of initial teacher development and STEM education. For example, it will be interesting to uncover how preservice teachers experience the use of educational board games in their teaching. In addition, it will also be interesting to discover how educational board games can be used in other STEM subjects such as mathematics, technology, and physical science. Ultimately, more research is also required on the learning benefits of educational board games from a learner’s perspective.
The gender imbalance in STEM subjects dominates current debates about women's underrepresentation in academia. However, women are well represented at the Ph.D. level in some sciences and poorly ...represented in some humanities (e.g., in 2011, 54% of U.S. Ph.D.'s in molecular biology were women versus only 31% in philosophy). We hypothesize that, across the academic spectrum, women are underrepresented in fields whose practitioners believe that raw, innate talent is the main requirement for success, because women are stereotyped as not possessing such talent. This hypothesis extends to African Americans' underrepresentation as well, as this group is subject to similar stereotypes. Results from a nationwide survey of academics support our hypothesis (termed the field-specific ability beliefs hypothesis) over three competing hypotheses.
The expectation is that pre-service teachers that are specializing in the teaching of primary school natural science, ought to make use of teaching approaches that will allow them to engage learners ...in a joyful yet meaningful science learning experience. One such teaching approach to be considered is regarded as board game-based teaching. This paper investigated how natural science pre-service teachers experienced the development of educational science board games. This study draws on a conceptual understanding of game-based education, which allows for the integration of topics within board game mechanics, board game aesthetics and board game thinking. This qualitative case study considered a focus-group discussion and photo-voice methodology as data collection techniques to capture the pre-service teachers' experiences on the development of educational science board games. Findings from the study revealed how their engagement in the development of educational science board games had an impact on their personal skill development, their professional teacher development, their development of pedagogical content knowledge, as well as their development of applicable assessment methodology that relates to the teaching of the subject natural science. On the other hand, issues surrounding the learning objectives, the complex design processes, and the lack of relevant materials available to develop the educational science board games were viewed in a less positive light. Findings from the study suggest that science teacher education programmes should be intentional in shaping pre-service teachers' skills to develop educational board games that would complement the quality of their science teaching practice.
This book presents a systematic review on traditional Arab herbal medicine including historical background, medical innovations introduced by Arab physicians, common roots of Arab medicine and ...western medicine, methodology of drug discovery and therapy in Arabic and Islamic medicine, a state-of-the-art description of traditional Arab herbal medicine, and evidence-based safety and efficacy of Arab and Islamic medicines. The usage of modern cell biological, biochemical, in vitro and in vivo techniques for the evaluation of medicinal plant safety and efficacy is also discussed. The toxicity of herbal formulations safety, quality assurances, and chemical analytical techniques are introduced in this book.
Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a ...community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850-2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.
Aim
Plant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the ...assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits.
Location
Tundra biome.
Time period
Data collected between 1964 and 2016.
Major taxa studied
295 tundra vascular plant species.
Methods
We compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species‐level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and species composition of functional groups to alternative classifications generated using post hoc clustering of species‐level traits.
Results
Traditional functional groups explained significant differences in trait expression, particularly amongst traits associated with resource economics, which were consistent across sites and at the biome scale. However, functional groups explained 19% of overall trait variation and poorly represented differences in traits associated with plant size. Post hoc classification of species did not correspond well with traditional functional groups, and explained twice as much variation in species‐level trait expression.
Main conclusions
Traditional functional groups only coarsely represent variation in well‐measured traits within tundra plant communities, and better explain resource economic traits than size‐related traits. We recommend caution when using functional group approaches to predict tundra vegetation change, or ecosystem functions relating to plant size, such as albedo or carbon storage. We argue that alternative classifications or direct use of specific plant traits could provide new insights for ecological prediction and modelling.
The strontium isotope signature ( 87 Sr/ 86 Sr) of calcite precipitated in rock fractures and faults is a frequently used tool to trace paleofluid flow. However, bedrock fracture networks, such as in ...Precambrian cratons, have often undergone multiple fracture reactivations resulting in complex sequences of fracture mineral infillings. This includes numerous discrete calcite crystal overgrowths. Conventional 87 Sr/ 86 Sr analysis of dissolved bulk samples of such crystals is not feasible as they will result in mixed signatures of several growth zonations. In addition, the zonations are too fine-grained for sub-sampling using micro-drilling. Here, we apply high spatial resolution 87 Sr/ 86 Sr spot analysis (80 µm) in transects through zoned calcite crystals in deep Paleoproterozoic granitoid fractures using laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) to trace discrete signs of paleofluid flow events. We compare the outermost calcite growth zone with 87 Sr/ 86 Sr values of the present-day groundwater sampled in the same boreholes to distinguish potential modern precipitates. We then connect our results to previously reported radiometric dating and C and O isotope signatures to understand the temporal history and physicochemical evolution of fluid flow within the fractures. Comparisons of modern calcite precipitated in a borehole over a period of 17 years with modern waters prove the concept of using 87 Sr/ 86 Sr as a marker for fluid origin in this environment and for how 87 Sr/ 86 Sr changed during marine water infiltration. Intermittent calcite precipitation over very long time spans is indicated in calcite of the currently open fractures, showing an evolution of 87 Sr/ 86 Sr from ~0.705–0.707—a population dated to ~1.43 billion years—to crystal overgrowth values at ~0.715–0.717 that overlap with the present-day groundwater values. This shows that high spatial resolution Sr isotope analysis of fine-scaled growth zonation within single calcite crystals is applicable for tracing episodic fluid flow in fracture networks
Ungulate trampling modifies soils and interlinked ecosystem functions across biomes. Until today, most research has focused on temperate ecosystems and mineral soils while trampling effects on cold ...and organic matter‐rich tundra soils remain largely unknown.
We aimed to develop a general model of trampling effects on soil structure, biota, microclimate and biogeochemical processes, with a particular focus on polar tundra soils. To reach this goal, we reviewed literature about the effects of trampling and physical disturbances on soils across biomes and used this to discuss the knowns and unknowns of trampling effects on tundra soils.
We identified the following four pathways through which trampling affects soils: (a) soil compaction; (b) reductions in soil fauna and fungi; (c) rapid losses in vegetation biomass and cover; and (d) longer term shifts in vegetation community composition.
We found that, in polar tundra, soil responses to trampling pathways 1 and 3 could be characterized by nonlinear dynamics and tundra‐specific context dependencies that we formulated into testable hypotheses.
In conclusion, trampling may affect tundra soil significantly but many direct, interacting and cascading responses remain unknown. We call for research to advance the understanding of trampling effects on soils to support informed efforts to manage and predict the functioning of tundra systems under global changes.
A free Plain Language Summary can be found within the Supporting Information of this article.
A free Plain Language Summary can be found within the Supporting Information of this article.
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