Structure Builders Research Articles

Small but mighty: Impacts of rodent‐herbivore structures on carbon and nutrient cycling in arctic tundra

Abstract Understanding arctic ecosystem function is key to understanding future global carbon (C) and nutrient cycling processes. However, small mammal herbivores can have effects on ecosystems as structure builders and these effects have been underrepresented in the understanding of arctic systems. We examined the impact of small mammal structures (hay piles, runways, latrines) on soils and plants in three arctic tundra regions near Utqiaġvik, Toolik Lake, and Nome, Alaska. Our aims were to (1) examine how vole and lemming structures influence plant and soil nutrient pools and microbial processes, (2) determine if structure effects were similar across tundra system types, and (3) understand how changes in the abundance and cover of these structures during different phases of small mammal multi‐annual population cycles might influence biogeochemical cycling. In general, small mammal structures increased nitrogen (N) availability in soils, although effects varied by study region. Across study regions, hay piles were relatively uncommon (lowest % cover) but increased multiple soil N and P pools, C‐ and N‐acquiring enzyme activities, and leaf phosphorus (P) concentrations, with the specific nutrient variables and size of the effects varying by study region. Latrines had the second highest cover and influenced multiple C, N and P pools, but their effects were mainly observed within a single region. Lastly, runways had the highest % cover of all activity types but increased the fewest number of soil nutrient variables. We conclude that by influencing soil nutrient availability and biogeochemical cycling, small mammal structures can influence bottom‐up regulation of ecosystem function, particularly during the high phase of the small mammal population cycle. Future changes in these population cycles might alter the role of small mammals in the Arctic and have lasting effects on system processes. Read the free Plain Language Summary for this article on the Journal blog

Individual Differences in Structure Building: Impacts on Comprehension and Learning, Theoretical Underpinnings, and Support for Less Able Structure Builders

In this article, we highlight an underappreciated individual difference: structure building. Structure building is integral to many everyday activities and involves creating coherent mental representations of conversations, texts, pictorial stories, and other events. People vary in this ability in a way not generally captured by other better known concepts and individual difference measures. Individuals with lower structure-building ability consistently perform worse on a range of comprehension and learning measures than do individuals with higher structure-building ability, both in the laboratory and in the classroom. Problems include a range of comprehension processes, including encoding factual content, inhibiting irrelevant information, and constructing a cohesive situation model of a text or conversation. Despite these problems, recent research is encouraging in that techniques to improve the learning outcomes for low-ability structure builders have been identified. We argue that the accumulated research warrants the recognition of structure building as an important individual difference in cognitive functioning and that additional theoretical work is needed to understand the underpinnings of structure-building deficits.

APA-Style Citations Can Create a Roadblock to Textbook Comprehension for Less Skilled Readers

We examined the effect of in-text American Psychological Association (APA)-style citations on quiz performance as a function of structure building ability, measured by the Multi-Media Comprehension Battery. Participants were randomly assigned to either APA or no citation conditions and asked to read an expository text followed by a comprehension quiz. Less skilled structure builders performed significantly lower on a comprehension quiz and read faster in the APA citation compared to the no citation condition. In contrast, skilled structure builders performed equally well on the comprehension quiz but had to reduce their reading speed in the APA citation condition. The results challenge the utility of in-text APA citations in textbooks targeted at general populations of students, particularly for moderate to poor comprehenders.

Studies on reconstruction of the Holy Cross wooden church in Wodzisław Śląski

Wooden churches used to commonly appear in Silesia through the past centuries. Their location was the result of local people’s needs and the accessibility of materials necessary to construct them. The form and the nature of those churches were the fruit of intermingling influences of various national cultures of the inhabitants of those areas, craftsmanship experience of various structure builders and depended on the extent of wealth of the cities, towns and villages they were erected in. Wodzisław Śląski was among the places with wooden sacred objects, in the 19th century, it was a small town with population consisting mainly of Poles, Germans and Jews.The Holy Cross wooden church was a hospital object. The church itself was situated on top of a low hill with a brook flowing in its direct vicinity. In the periods of heavy rainfalls, the rapid stream used to wash out the hill, thus, affecting the church foundations, directly contributing to deterioration of the structure’s technical condition. The critically bad condition of the church structure was the main reason for the decision to pull it down after 1826. Throughout the recent years, the growth of the local patriotism induced the interest in the town’s history and its historical panorama. Relatively few pieces of information on the church and no drawings thereof have been preserved. The archeological and architectural research revealed a lot of interesting facts related to the church and concerning its structure and its supposed non-typical form. A realistic method to satisfy the curiosity how the church looked like in the period of its splendor was the construction of its model based on the research and studies carried out, the very construction of the miniature model in progress being a test site verifying some suppositions about the church’s appearance. The model built was added to the exhibits of the Wodzisław Śląski Museum, becoming a contribution to the discussion on methods of the dissemination of information on the historical view of the town and including the research results in the papers concerning the future form and the panorama of modern Wodzisław Śląski.

Effects of Flashcards on Learning Authentic Materials: The Role of Detailed Versus Conceptual Flashcards and Individual Differences in Structure-Building Ability

Little research has examined the fruitfulness of flashcards for improving learning outcomes of authentic classroom material. In Experiment 1, across different content areas flashcards did not significantly increase performance on a final test relative to the free-study condition. Experiment 2 investigated whether providing conceptual flashcards would aid participants’ learning relative to detailed flashcards (the kind generated most frequently by participants). Conceptual flashcards produced superior short-answer test performance than detailed flashcards for less able learners (low structure builders) but not for more able learners (high structure builders). The limited benefits of flashcards appear to reflect several factors: the current sample of students generally recruited effective study strategies (in the free-study condition) and the preponderance of detailed flashcards in both textbook provided materials and student-generated flashcards. Consistent with the material-appropriate processing framework, detailed but not conceptual flashcards would be redundant with encoding normally invited by didactic materials.

Understanding the cognitive processes involved in writing to learn.

Writing is often used as a tool for learning. However, empirical support for the benefits of writing-to-learn is mixed, likely because the literature conflates diverse activities (e.g., summaries, term papers) under the single umbrella of writing-to-learn. Following recent trends in the writing-to-learn literature, the authors focus on the underlying cognitive processes. They draw on the largely independent writing-to-learn and cognitive psychology learning literatures to identify important cognitive processes. The current experiment examines learning from 3 writing tasks (and 1 nonwriting control), with an emphasis on whether or not the tasks engaged retrieval. Tasks that engaged retrieval (essay writing and free recall) led to better final test performance than those that did not (note taking and highlighting). Individual differences in structure building (the ability to construct mental representations of narratives; Gernsbacher, Varner, & Faust, 1990) modified this effect; skilled structure builders benefited more from essay writing and free recall than did less skilled structure builders. Further, more essay-like responses led to better performance, implicating the importance of additional cognitive processes such as reorganization and elaboration. The results highlight how both task instructions and individual differences affect the cognitive processes involved when writing-to-learn, with consequences for the effectiveness of the learning strategy. (PsycINFO Database Record

Structure building differences influence learning from educational text: Effects on encoding, retention, and metacognitive control

Structure building describes the process by which people mentally organize information while reading to comprehend and later recall text. We investigated how individual differences in structure building ability affect students' learning of complex, educational texts. College students studied a complex text with a mechanical theme, engaged in retrieval practice, made metamemory judgments, and then were given another study opportunity. Following a short delay, memory and comprehension of the text were assessed with a range of dependent measures, including performance on free recall, multiple-choice questions, and problem-solving questions. Participants with high structure building ability outperformed those with low structure building ability on information recalled, factual and inference multiple-choice questions, and problem solving questions. Although high and low structure builders demonstrated equivalent metamemory accuracy, high structure builders appear to better regulate their restudy time according to a discrepancy reduction strategy, which allowed them to acquire more new information that they were unable to retrieve initially during recitation. Our findings suggest that low structure builders may suffer from deficiencies at many levels of text representations as well as deficiencies in metacognitive control during restudy. Our study highlights structure building ability as an important individual difference for learning educational texts and furthers our understanding of exactly what aspects of learning are related to these differences.

Enhancing learning during lecture note-taking using outlines and illustrative diagrams

The current study examined the effects of providing learning aids during a lecture on later test performance, and its relationship to structure-building ability. Before taking notes on an audio lecture, participants were either given a skeletal outline, an illustrative diagram, or no learning aid at all. After the lecture, participants were given a free recall test and a short-answer test that probed understanding of target concepts (requiring explanation). For low-ability structure builders, outlines improved free recall but not short-answer performance compared to the no-aid control condition. By contrast, providing high-ability structure builders with outlines improved free recall and short-answer performance (relative to the control). An illustrative diagram improved free recall and short-answer performance compared to the control condition, regardless of structure-building ability. Thus, these aids are generally useful for improving learning while listening to a lecture. Implications for the more specific enhancement patterns for low-ability structure builders are discussed.

Functional Characteristics of Egg White Proteins within Wheat, Rye, and Germinated-Rye Sourdoughs

Egg white (EW) proteins are functional proteins, which possess certain biological activities (antimicrobial, antigenic, and peptidase-inhibitory) that may influence the food processing or vice versa can be affected by processing. This study investigated the behavior of EW proteins within sourdough systems with respect to proteolysis and fermentation parameters, and the ability of EW to build foam structures with sourdoughs. Of the EW proteins, ovotransferrin was hydrolyzed in all sourdoughs (wheat, rye, and germinated-rye), whereas the breakdown of ovalbumin was specific for germinated-rye sourdoughs, with the cysteine endopeptidases being responsible for the hydrolysis. The presence of EW in sourdough fermentations had no influence on the prolamin hydrolysis or the growth of starter culture, indicating that the peptidase-inhibitory and antimicrobial properties of EW play no important role in sourdoughs. EW foams, however, appeared as potential structure builders in sourdough applications and could serve as alternative structural agents in the production of baked goods with low gluten content.

The benefits of embedded question adjuncts for low and high structure builders.

The effectiveness of two types of adjunct questions, standard embedded questions and why questions (elaborative interrogation), was investigated for readers differing in structure-building ability (Gernsbacher, 1990). Participants read a textbook chapter either with or without the adjunct questions. Learning was assessed with typical classroom testing methods (multiple choice, short answer). Also, relatedness ratings were used to assess the coherence of learners' representations. High structure builders generally outperformed low structure builders. However, embedded questions but not elaborative interrogation improved the low structure builders' test performances on information targeted by and related to the adjunct questions. Neither study method improved test performance for the high comprehenders. Embedded questions also stimulated more coherent representations. Results indicate that embedded questions are an effective study method for low comprehenders.

Chemoinformatics: Past, Present, and Future.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Chemoinformatics: Past, Present, and Future†

The history of chemoinformatics is reviewed in a decade-by-decade manner from the 1940s to the present. The focus is placed on four traditional research areas: chemical database systems, computer-assisted structure elucidation systems, computer-assisted synthesis design systems, and 3D structure builders. Considering the fact that computer technology has been one of the major driving forces of the development of chemoinformatics, each section will start from a brief description of the new advances in computer technology of each decade. The summary and future prospects are given in the last section.

Causality and Tense—Two Temporal Structure Builders

By force of causes precede effects, causality contributes to the temporal meaning of discourse. In case of semantic causal relations, this contribution is straightforward, but in case of epistemic causal relations, it is not. In order to gain insight into the semantics of epistemic causal relations, paradoxical cases are analyzed of text fragments in which temporal and causal meaning seem to be irreconcilable. A solution is proposed consisting of several parts: First, an analysis of epistemic causal coherence relations, in which the effect sentence is argued to be a (covert) belief sentence. Secondly, a method for deriving (epistemic) causal coherence relations. And thirdly, a format for representing temporal meaning in which contributions of tense and causality can be reconciled. Finally, it is argued that understanding epistemically causally connected sequences (or: argumentation) is not equal to being persuaded to believing them. The difference is shown to be expressible in the representation format proposed.

Interspecific attractiveness of structures built by courting male fiddler crabs: experimental evidence of a sensory trap

Male fiddler crabs Uca musica sometimes build sand hoods and male Uca beebei sometimes build mud pillars next to their burrows to which they attract females for mating. Mate-searching females preferentially approach these structures and subsequently mate with structure builders. Here we show that the preference for structures is not species-specific and argue that it may not have evolved for mate choice. When not near burrows, many species of fiddler crabs approach and temporarily hide near objects, suggesting that hoods and pillars may attract females because they elicit this general predator-avoidance behavior. To test this sensory trap hypothesis we individually released female U. musica, U. beebei and Uca stenodactylus, a non-builder, in the center of a circular array of empty burrows to which we added hoods and pillars and then moved a model predator toward the females. All species ran to structures to escape the predator and the two builders preferred hoods. Next, we put hood replicas on male U. beebei burrows and pillar replicas on male U. musica burrows. When courted, females of both species preferentially approached hoods as they did when chased with a predator. However, males of both species with hoods did not have higher mating rates than males with pillars perhaps because hoods block more of a male's visual field so he sees and courts fewer females. Sexual selection may often favor male signals that attract females because they facilitate general orientation or navigation mechanisms that reduce predation risk in many contexts, including during mate search.

When Text Difficulty Benefits Less-Skilled Readers

The mnemonic effects of increased text difficulty were examined for skilled and less skilled college readers for fairy tales and expository texts. One difficulty manipulation was designed to encourage relational processing of the ideas in the text and the other was designed to encourage more controlled processing of individual text elements (words). Replicating past studies, skilled readers, as indexed either by Nelson-Denny tests or Gernsbacher (1990) structure-building tests, showed no disruption in recall by either difficulty manipulation; indeed their recall was enhanced for certain combinations of difficulty manipulation and text type. Less skilled Nelson-Denny readers but not less skilled structure builders showed consistent declines in recall after they performed the difficult task that challenged word processing. In contrast, the difficult task that promoted encoding of relational information improved recall for both types of less skilled readers. This complex pattern is inconsistent with two straightforward views of how difficulty might affect text memory for less able readers. The results instead suggest that selective deficiency and processing enhancement are both important in text difficulty effects.