Prior Content Knowledge Research Articles

Relações entre Biologia e Educação Física: olhar de especialistas sobre uma proposta de sequência didática

A atual organização curricular de grande parte das escolas brasileiras se apresenta de forma fragmentada e desconexa, o que limita o desenvolvimento global e integrado das competências e habilidades dos alunos. Os projetos ou sequências didáticas interdisciplinares surgem como uma opção para superar tal limitação. Entretanto, existem poucos estudos que abordam experiências de integração curricular na Escola. O objetivo desse trabalho foi elaborar, a partir do referencial teórico da interdisciplinaridade, uma sequência didática visando a integração das disciplinas Biologia e Educação Física, a partir do tema Fisiologia do Exercício e submetê-la à análise de especialistas das duas disciplinas a fim de avaliar a viabilidade de realizar a proposta com alunos do Ensino Fundamental II. Os pareceres dos avaliadores das duas disciplinas indicaram que a sequência didática apresentou aspectos positivos como a diversidade e criatividade das atividades, a preocupação com o levantamento de conhecimentos prévios e contextualização dos conteúdos com a vida dos alunos, aspectos considerados importantes no processo de aprendizagem. A sequência elaborada, segundo os avaliadores, é passível de aplicação segundo aspectos de conteúdo e compatível com objetivos propostos, embora tenha sido ressaltada a dificuldade de encontrar uma escola com a disponibilidade de realizar um trabalho interdisciplinar como foi proposto, devido a disponibilidade de tempo, e organização do horário dos professores e ao currículo fragmentado presente atualmente nas escolas. A sequência permite ainda ao professor o exercício reflexivo, que contribui para o aprimoramento da sua prática.

Increasing Student Access to Content Area Textbooks

Teachers, particularly at the middle and high school levels, rely heavily on textbooks to deliver curricular content. Often, students are asked to dive right into the content of a textbook that may or may not contain relevant information, is difficult to navigate, or requires prior content knowledge they do not have. To combat these issues and maximize the utility of textbooks, they must be selected carefully and implemented soundly. Yet, even these steps may not enable all students, specifically those with disabilities, to access them. Fortunately, digital textbooks may be an accessible option for some students. This article provides suggestions on (a) how teachers can carefully select textbooks, (b) effective methods for implementing textbooks, and (c) accessibility ideas for digital text for students with disabilities.

Patchwork: allele-specific copy number analysis of whole-genome sequenced tumor tissue.

Whole-genome sequencing of tumor tissue has the potential to provide comprehensive characterization of genomic alterations in tumor samples. We present Patchwork, a new bioinformatic tool for allele-specific copy number analysis using whole-genome sequencing data. Patchwork can be used to determine the copy number of homologous sequences throughout the genome, even in aneuploid samples with moderate sequence coverage and tumor cell content. No prior knowledge of average ploidy or tumor cell content is required. Patchwork is freely available as an R package, installable via R-Forge (http://patchwork.r-forge.r-project.org/).

Diagrammatic Literacy in Secondary Science Education

Students in secondary science education seem to have difficulties with understanding diagrams. The present study focused on explanatory factors that predict students’ difficulties with process diagrams, i.e., diagrams that describe a process consisting of components that are related by arrows. From 18 compulsory national Biology exams of secondary school pre-university students, all process diagram tasks (n = 64) were included in corpus. Features of the task, student, and diagram were related to the difficulty of that particular task, indicated by the cohort mean exam score. A hierarchical regression analysis showed main effects for (1) the cognitive task demand, (2) the familiarity of the components, and (3) the number of components in a diagram. All these main effects were in the expected direction. We also observed interactions. Within the category of tasks with a high cognitive demand, tasks about a diagram of which students have low prior content knowledge were more difficult than tasks about a diagram of which students have high prior content knowledge. Tasks with a high cognitive demand about a diagram with familiar arrows were, surprisingly, more difficult than tasks with a high cognitive demand about a diagram with unfamiliar arrows. This latter finding might be attributed to compensation for task difficulty by the large number of components in the diagrams involved. The final model explained 46 % of the variance in exam scores. These results suggest that students have difficulties (1) with tasks that require a deeper understanding when the content is new, (2) with diagrams that use unfamiliar component conventions, and (3) with diagrams that have a small number of components and are therefore probably more abstract.

The Effects of Glossary and Read-Aloud Accommodations on English Language Learners’ Performance on a Mathematics Assessment

Glossary and reading aloud test items are commonly allowed in many states' accommodation policies for English language learner (ELL) students for large-scale mathematics assessments. However, little research is available regarding the effects of these accommodations on ELL students' performance. Further, no research exists that examines how students use the accommodations. Using a randomized experimental design and think-aloud procedure, the present study explored the effects of the two accommodations. Results showed no significant effect of glossary, mixed effects of read aloud, and significant interaction effects between students' prior content knowledge and accommodations, which suggests the accommodation was effective for students with content knowledge. Think-aloud data indicated that students were not familiar with, and did not actively utilize the glossary. Implications for the effective use of accommodations and future research are discussed.

Science teachers and scientific argumentation: Trends in views and practice

AbstractCurrent research indicates that student engagement in scientific argumentation can foster a better understanding of the concepts and the processes of science. Yet opportunities for students to participate in authentic argumentation inside the science classroom are rare. There also is little known about science teachers' understandings of argumentation, their ability to participate in this complex practice, or their views about using argumentation as part of the teaching and learning of science. In this study, the researchers used a cognitive appraisal interview to examine how 30 secondary science teachers evaluate alternative explanations, generate an argument to support a specific explanation, and investigate their views about engaging students in argumentation. The analysis of the teachers' comments and actions during the interview indicates that these teachers relied primarily on their prior content knowledge to evaluate the validity of an explanation rather than using available data. Although some of the teachers included data and reasoning in their arguments, most of the teachers crafted an argument that simply expanded on a chosen explanation but provided no real support for it. The teachers also mentioned multiple barriers to the integration of argumentation into the teaching and learning of science, primarily related to their perceptions of students' ability levels, even though all of these teachers viewed argumentation as a way to help students understand science. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 1122–1148, 2012

Predictive Top-Down Integration of Prior Knowledge during Speech Perception

A striking feature of human perception is that our subjective experience depends not only on sensory information from the environment but also on our prior knowledge or expectations. The precise mechanisms by which sensory information and prior knowledge are integrated remain unclear, with longstanding disagreement concerning whether integration is strictly feedforward or whether higher-level knowledge influences sensory processing through feedback connections. Here we used concurrent EEG and MEG recordings to determine how sensory information and prior knowledge are integrated in the brain during speech perception. We manipulated listeners' prior knowledge of speech content by presenting matching, mismatching, or neutral written text before a degraded (noise-vocoded) spoken word. When speech conformed to prior knowledge, subjective perceptual clarity was enhanced. This enhancement in clarity was associated with a spatiotemporal profile of brain activity uniquely consistent with a feedback process: activity in the inferior frontal gyrus was modulated by prior knowledge before activity in lower-level sensory regions of the superior temporal gyrus. In parallel, we parametrically varied the level of speech degradation, and therefore the amount of sensory detail, so that changes in neural responses attributable to sensory information and prior knowledge could be directly compared. Although sensory detail and prior knowledge both enhanced speech clarity, they had an opposite influence on the evoked response in the superior temporal gyrus. We argue that these data are best explained within the framework of predictive coding in which sensory activity is compared with top-down predictions and only unexplained activity propagated through the cortical hierarchy.

A Transition Program for Underprepared Students in General Chemistry: Diagnosis, Implementation, and Evaluation

We developed an online exam to diagnose students who are underprepared for college-level general chemistry and implemented a program to support them during the general chemistry sequence. This transition program consists of extended-length recitations, peer-led team-learning (PLTL) study groups, and peer-mentoring groups. We evaluated this program's impact on student performance in general chemistry using data from the fall semesters 2007, 2008, and 2009. We found that our transition program helped the underprepared students make significant gains in their course performance relative to other students when controlling for prior content knowledge and experience. PLTL did improve the performance of the underprepared students relative to other students in the lower 40% of the class. Inclusion of peer mentoring resulted in additional gains over the use of PLTL. Via surveys to students in the transition program, students agreed or strongly agreed that extended-length recitations and peer-mentoring groups improved their performance in general chemistry. This is important given the voluntary nature of our program.

Effects of auditory priming on speech recognition in combination with spatial and fluctuating masker benefits

This presentation will discuss research on three individual causes of release from masking in speech recognition as well as the interactions among them. Spatial differences between target and masker produce release from masking through head shadow effects, binaural processing of interaural differences, and, under some specific circumstances, perceived spatial differences between target and masker. A second frequently-studied type of masking release occurs when fluctuations in a masker's amplitude envelope over time create temporal epochs in which speech-to-masker ratios are very favorable. The efficiency of masking is also reduced when a listener's prior knowledge of message content reduces uncertainty about what s/he will hear, a process often called auditory priming. This presentation will describe a series of recent experiments that consider factors that affect auditory priming and fluctuating masker benefit, individually and when combined with spatial cues. [Work supported by NIDCD DC01625.]

Relationship between nature of science understandings and argumentation skills: A role for counterargument and contextual factors

AbstractThe study investigated the relationship of high school students' understandings about nature of science (NOS) aspects and their argumentation skills in relation to two controversial socioscientific issues. The study was conducted in five schools selected from different geographical areas in Beirut, Lebanon. Participants were 219 grade 11 students. Students in all the schools were administered a survey that consisted of two scenarios that addressed the controversial socioscientific issues about genetically modified food and water fluoridation. The two scenarios were followed by questions relating to argumentation and NOS. The study used a mixed methods approach where quantitative and qualitative measures were employed. Analysis involved participants' views of the target NOS aspects (subjective, tentative, and empirical) and their argumentation components (argument, counterargument, and rebuttal). The Pearson analyses showed strong correlations between the counterargument, compared to argument and rebuttal, and the three NOS aspects. Further, the chi‐square analyses showed significant differences in participants' argumentation skills and NOS understandings between the two scenarios. Qualitative data from questionnaires and interviews further confirmed these findings. Two central implications for the teaching of NOS and argumentation skills were discussed in terms of highlighting the role of counterarguments and considering contextual factors that involve issue exposure and familiarity, prior content knowledge, and personal relevance. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 489–514, 2012

Rapid Microsatellite Identification from Illumina Paired-End Genomic Sequencing in Two Birds and a Snake

Identification of microsatellites, or simple sequence repeats (SSRs), can be a time-consuming and costly investment requiring enrichment, cloning, and sequencing of candidate loci. Recently, however, high throughput sequencing (with or without prior enrichment for specific SSR loci) has been utilized to identify SSR loci. The direct “Seq-to-SSR” approach has an advantage over enrichment-based strategies in that it does not require a priori selection of particular motifs, or prior knowledge of genomic SSR content. It has been more expensive per SSR locus recovered, however, particularly for genomes with few SSR loci, such as bird genomes. The longer but relatively more expensive 454 reads have been preferred over less expensive Illumina reads. Here, we use Illumina paired-end sequence data to identify potentially amplifiable SSR loci (PALs) from a snake (the Burmese python, Python molurus bivittatus), and directly compare these results to those from 454 data. We also compare the python results to results from Illumina sequencing of two bird genomes (Gunnison Sage-grouse, Centrocercus minimus, and Clark's Nutcracker, Nucifraga columbiana), which have considerably fewer SSRs than the python. We show that direct Illumina Seq-to-SSR can identify and characterize thousands of potentially amplifiable SSR loci for as little as $10 per sample – a fraction of the cost of 454 sequencing. Given that Illumina Seq-to-SSR is effective, inexpensive, and reliable even for species such as birds that have few SSR loci, it seems that there are now few situations for which prior hybridization is justifiable.

Effects of aging on the ability to benefit from prior knowledge of message content in masked speech recognition

Under conditions in the presence of competing talkers, presenting the early part of a target sentence in quiet improves recognition of the last keyword of the sentence. This content-priming effect depends on a working-memory resource holding the information of the early presented part of the target speech (the content prime). Older adults usually exhibit declined working memory and experience more difficulties in speech recognition under “cocktail-party” conditions. This study investigated whether speech masking also affects recall of the content prime and whether the content-priming effect declines in older adults. The results show that in both younger adults and older adults, although the content prime was heard in quiet, recall of keywords in the prime was significantly affected by the signal-to-masker ratio of the target/masker presentation. The vulnerability of prime recall to speech masking was larger in older adults than that in younger adults. Also, the content-priming effect disappeared in older adults, even though older adults are able to use the content prime to determine the target speech in the presence of competing talkers. Thus, a speech masker affects not only recognition but also recall of speech, and there is an age-related decline in both content-priming-based unmasking of the target speech and recall of the prime.

SMEPOC– a computer program for the automatic generation of trial structural models for inorganic compounds with symmetry restriction

A new structure modelling algorithm that can automatically generate trial structure models based on a prior knowledge of the unit-cell content and space-group information is proposed. It can enumerate all possible equivalent position combination (EPC) models and eliminate unreasonable ones with symmetry restriction. Unlike other methods, it does not require the internal molecular connectivity or coordination polyhedron information and is mostly suitable for modelling inorganic crystals with independent atoms. Therefore, these EPC models can be used as input to global optimization procedures for inorganic crystal structure determination using powder diffraction data by the direct-space method. The efficiency of the direct-space method can be greatly improved using this EPC method because the global optimization problem in a 3N-parameter space can be divided into a set of simpler ones. A program,SMEPOC, that can generate all possible EPC models for further global optimization procedures has been developed and is now available from the authors upon request.

Survey of Pseudomonas aeruginosa and its phages: de novo peptide sequencing as a novel tool to assess the diversity of worldwide collected viruses

A collection of 15 newly isolated (bacterio)phages infecting the opportunistic pathogen Pseudomonas aeruginosa was established to investigate their global diversity and potential in phage therapy. These phages were sampled in 14 different countries traversing four continents, from both natural environments and hospital sewage. They all display unique DNA and protein profiles and cluster morphologically into six groups within the three major families of the Caudovirales. Extensive host range studies on a library of 122 AFLP-genotyped clinical P. aeruginosa strains (of which 49 were newly isolated at the University Hospital of Leuven, Belgium) showed that the phages lysed 87% of the strains. Infection analysis of outer membrane mutants identified 10 phages as type IV pili-dependent. More detailed information about the evolutionary relatedness of the phages was gathered by de novo peptide sequencing of major virion proteins using tandem Matrix-Assisted Laser Desorption/Ionization Time of Flight technology. Applying this technique for the first time to viruses, seven groups of closely related phages were identified without the need of prior knowledge of genome content and/or electron microscopic imaging. This study demonstrates both the epidemic population structure of P. aeruginosa and the global spread of P. aeruginosa phage species, and points at the resistance of two clinically predominant, widespread P. aeruginosa strains against phage attack.

Learning Using Dynamic and Static Visualizations: Students’ Comprehension, Prior Knowledge and Conceptual Status of a Biotechnological Method

The importance of biotechnology education at the high-school level has been recognized in a number of international curriculum frameworks around the world. One of the most problematic issues in learning biotechnology has been found to be the biotechnological methods involved. Here, we examine the unique contribution of an animation of the polymerase chain reaction (PCR) in promoting conceptual learning of the biotechnological method among 12th-grade biology majors. All of the students learned about the PCR using still images (n = 83) or the animation (n = 90). A significant advantage to the animation treatment was identified following learning. Students’ prior content knowledge was found to be an important factor for students who learned PCR using still images, serving as an obstacle to learning the PCR method in the case of low prior knowledge. Through analysing students’ discourse, using the framework of the conceptual status analysis, we found that students who learned about PCR using still images faced difficulties in understanding some mechanistic aspects of the method. On the other hand, using the animation gave the students an advantage in understanding those aspects.

Coherence Marking, Prior Knowledge, and Comprehension of Informative and Persuasive Texts: Sorting Things Out

Coherence plays a central role when readers construct meaning from a text. Previous research has shown how coherence marking affects text processing and representation. However, this effect seems to depend on reader's prior knowledge of the text content: Low knowledge readers benefit from coherence marking, whereas high knowledge readers benefit from a more implicit text (McNamara & Kintsch, 1996). Because this interaction was not consistently found in previous research, this article takes a closer look at the operationalization of the experimental variables: coherence marking, prior knowledge, and text comprehension. Also, this article compares the effect on both informative and persuasive texts. Results indicate that linguistic marking of coherence indeed interacts with prior knowledge in the informative genre, but not in the persuasive genre.

Impact of prior content and meta‐cognitive knowledge on students' performance in an introductory accounting course

PurposeThe purpose of this study is to examine the impact of five factors, reflecting students' diversity in prior content and metacognitive knowledge, on students' academic performance in the introductory accounting course.Design/methodology/approachBased on a conceptual framework of prior knowledge, five factors are hypothesised to have an impact on students' performance. They are: prior accounting knowledge, age, gender, intended academic major, and first language. A self‐administered questionnaire is completed by students enrolled in the compulsory introductory accounting course at a large multi‐campus NZ university. Multivariate analysis is carried out to test the research hypotheses and the predictive ability of the five independent variables on students' performance.FindingsConsistent with the educational psychology literature, prior content knowledge has a significant impact. Students' metacognitive knowledge, which differs according to their language and gender, also has a significant effect on students' performance.Research limitations/implicationsThe low R2 in the regression model suggests that, although some of the study variables are significant, a high proportion of variation in academic performance remains unexplained by the model. The results may also not be representative of student population in general as information is elicited from students from one particular university. Future research could extend the sample to more than one tertiary institution and consider the effect of other potential variables such as students' intrinsic motivation and learning strategies.Originality/valueUnlike many prior studies which lacked a theoretical framework to support their research, this study proposes a conceptual framework drawn from the education psychology literature for examining students' performance in the introductory accounting course.

Learning via Direct and Mediated Instruction by Deaf Students

Four experiments investigated classroom learning by deaf college students receiving lectures from instructors signing for themselves or using interpreters. Deaf students' prior content knowledge, scores on postlecture assessments of content learning, and gain scores were compared to those of hearing classmates. Consistent with prior research, deaf students, on average, came into and left the classroom with less content knowledge than hearing peers, and use of simultaneous communication (sign and speech together) and American Sign Language (ASL) apparently were equally effective for deaf students' learning of the material. Students' self-rated sign language skills were not significantly related to performance. Two new findings were of particular importance. First, direct and mediated instruction (via interpreting) were equally effective for deaf college students under the several conditions employed here. Second, despite coming into the classroom with the disadvantage of having less content knowledge, deaf students' gain scores generally did not differ from those of their hearing peers. Possible explanations for these findings are considered.

Perceptual clarity of speech modulates activity in left temporal‐lobe regions: fMRI correlates of top‐down influences

Behavioral evidence supports the idea that perception is guided by mechanisms that compute an input's most probable interpretation. For example, four‐band noise‐vocoded speech, which is largely unintelligible to naive listeners, becomes perceptually clear when listeners possess prior knowledge of the signal content ‐ a phenomenon we call “pop‐out”. Feedback connections within and among auditory cortical regions may allow cognitively “higher” levels of processing to predict and thus “explain” the bottom‐up signal. In the present study, we use fMRI to investigate the network underlying pop‐out. We use written primes (matching or nonmatching text strings) to manipulate a subject's perception of single noise‐vocoded words, thereby creating acoustically matched conditions that elicit the perceptions of intelligible or unintelligible speech. Whole brain fMRI data were gathered from 21 subjects using a sparse‐imaging procedure. Preliminary analysis reveals regions of statistically significant signal change along...

OXOPAP assay: For selective amplification of aminoacylated tRNAs from total cellular fractions

Transfer RNA (tRNA) plays a pivotal role in protein synthesis within cells, where it is recognized by one cognate aminoacyl-tRNA synthetase, in competition with the remaining non-cognate synthetases, and esterified with an amino acid. For many years the levels of tRNA aminoacylation, in a given population of cellular RNA, have been analyzed using methods that include northern analysis and/or oxidation techniques to separate aminoacylated from non-aminoacylated species. In the present report we describe an approach recently developed by us that combines oxidation-protection with polyadenylation and PCR. The OXOPAP approach permits the amplification of tRNA species that are nearly identical and that evade differential identification by more classical northern hybridization methods. Our approach also allows the identification of aminoacylatable “naïve” species, where no prior knowledge of sequence content is necessary for amplification.