374 research outputs found
Modeling the Relations Among Morphological Awareness Dimensions, Vocabulary Knowledge, and Reading Comprehension in Adult Basic Education Students
This study extended the findings of Tighe and Schatschneider (2015) by investigating the predictive utility of separate dimensions of morphological awareness as well as vocabulary knowledge to reading comprehension in Adult Basic Education (ABE) students. We competed 2- and 3-factor structural equation models of reading comprehension. A 3-factor model of real word morphological awareness, pseudoword morphological awareness, and vocabulary knowledge emerged as the best fit and accounted for 79% of the reading comprehension variance. The results indicated that the constructs contributed jointly to reading comprehension; however, vocabulary knowledge was the only potentially unique predictor (p = .052), accounting for an additional 5.6% of the variance. This study demonstrates the feasibility of applying a latent variable modeling approach to examine individual differences in the reading comprehension skills of ABE students. Further, this study replicates the findings of Tighe and Schatschneider (2015) of the importance of differentiating among dimensions of morphological awareness in this population
Electrodynamic Response and Stability of Molecular Crystals
We show that electrodynamic dipolar interactions, responsible for long-range
fluctuations in matter, play a significant role in the stability of molecular
crystals. Density functional theory calculations with van der Waals
interactions determined from a semilocal "atom-in-a-molecule" model result in a
large overestimation of the dielectric constants and sublimation enthalpies for
polyacene crystals from naphthalene to pentacene, whereas an accurate treatment
of non-local electrodynamic response leads to an agreement with the measured
values for both quantities. Our findings suggest that collective response
effects play a substantial role not only for optical excitations, but also for
cohesive properties of non-covalently bound molecular crystals
Student Behavior Ratings and Response to Tier 1 Reading Intervention: Which Students Do Not Benefit?
Core reading instruction and interventions have differential effects based on student characteristics such as cognitive ability and pre-intervention skill level. Evidence for differential effect based on affective characteristics is scant and ambiguous; however, students with problem behavior are more often non-responsive to core reading instruction and intensive reading interventions. In this study, we estimated the range of students\u27 behavior ratings in which a core reading instruction intervention was effective using a data set including 3,024 students in K-3. Data came from seven independent studies evaluating the individualized Student Instruction (ISI) Tier 1 reading intervention and were pooled using integrative data analysis. We estimated Johnson-Neyman intervals of student behavior ratings that showed a treatment effect both at the within and between classroom level. ISI was effective in improving reading scores (b = 0.51, p = .020, d = 0.08). However, students with very low or very high behavior ratings did not benefit from the approaches (range of behavior rating factor scores: -0.95-2.87). At the classroom level, students in classrooms with a higher average of problem behaviors did not benefit from ISI (average classroom behavior rating factor score: 0.05-4.25). Results suggest differentiating instruction alone is not enough for students with behavior problems to grow in reading ability
Quantitative isotope-dilution high-resolution-mass-apectrometry analysis of multiple intracellular metabolites in Clostridium autoethanogenum with uniformly 13C-labeled standards derived from Spirulina
We have investigated the applicability of commercially available lyophilized spirulina (Arthrospira platensis), a microorganism uniformly labeled with 13C, as a readily accessible source of multiple 13C-labeled metabolites suitable as internal standards for the quantitative determination of intracellular bacterial metabolites. Metabolites of interest were analyzed by hydrophilic-interaction liquid chromatography coupled with high-resolution mass spectrometry. Multiple internal standards obtained from uniformly (U)-13C-labeled extracts from spirulina were used to enable isotope-dilution mass spectrometry (IDMS) in the identification and quantification of intracellular metabolites. Extraction of the intracellular metabolites of Clostridium autoethanogenum using 2:1:1 chloroform/methanol/water was found to be the optimal method in comparison with freeze–thaw, homogenization, and sonication methods. The limits of quantification were ≤1 μM with excellent linearity for all of the calibration curves (R2 ≥ 0.99) for 74 metabolites. The precision and accuracy were found to be within relative standard deviations (RSDs) of 15% for 49 of the metabolites and within RSDs of 20% for all of the metabolites. The method was applied to study the effects of feeding different levels of carbon monoxide (as a carbon source) on the central metabolism and Wood–Ljungdahl pathway of C. autoethanogenum grown in continuous culture over 35 days. Using LC-IDMS with U-13C spirulina allowed the successful quantification of 52 metabolites in the samples, including amino acids, carboxylic acids, sugar phosphates, purines, and pyrimidines. The method provided absolute quantitative data on intracellular metabolites that was suitable for computational modeling to understand and optimize the C. autoethanogenum metabolic pathways active in gas fermentation
Language Variation in the Writing of African American Students: 6 Factors Predicting Reading Achievement
Purpose
This study aims to examine the predictive relation between measures obtained from African American students\u27 written narrative language samples and reading achievement, as measured by standardized academic assessments. Method
Written language samples were elicited from 207 African American students in Grades 1–8. The samples were examined for morphosyntactic variations from standardized written Generalized American English (GAE). These variations were categorized as either (a) specific to African American English (AAE) or (b) neutral across AAE and standardized written GAE (i.e., considered ungrammatical both in AAE and in standardized written GAE). Structural equation modeling was employed to then examine the predictive relation between the density of AAE-specific forms in students\u27 writing and their performance on standardized assessments of literacy and reading vocabulary. This relation was examined while accounting for the density of dialect-neutral morphosyntactic forms, reported family income, age, and written sample length. Results
The written samples were highly variable in terms of morphosyntax. Younger students and those from lower income homes tended to use AAE-specific forms at higher rates. However, the density of AAE-specific forms did not significantly predict standardized literacy scores or reading vocabulary after accounting for dialect-neutral variations, income, and sample length. Conclusions
These results support the ongoing need to better understand the language, literacy, and overall academic development of students from all backgrounds. It may be essential to focus on dialect-neutral language forms (i.e., morphosyntactic forms that are consistent across both AAE and standardized written GAE) in written samples to maximize assessment validity across students who speak varying dialects of English
A genome-scale model of Clostridium autoethanogenum reveals optimal bioprocess conditions for high-value chemical production from carbon monoxide
Clostridium autoethanogenum is an industrial microbe used for the commercial-scale production of ethanol from carbon monoxide. While significant progress has been made in the attempted diversification of this bioprocess, further improvements are desirable, particularly in the formation of the high-value platform chemicals, such as 2,3-butanediol. A new, experimentally parameterised genome scale model of C. autoethanogenum predicts dramatically increased 2,3-butanediol production under non-carbon-limited conditions when thermodynamic constraints on hydrogen production are considered
Complete Genome Sequence of the Barley Pathogen Xanthomonas translucens pv. translucens DSM 18974 T (ATCC 19319 T)
Jaenicke S, Bunk B, Wibberg D, et al. Complete Genome Sequence of the Barley Pathogen Xanthomonas translucens pv. translucens DSM 18974 T (ATCC 19319 T). Genome Announcements. 2016;4(6): e01334-16.We report here the complete 4.7-Mb genome sequence of Xanthomonas translucens pv. translucens DSM 18974T, which causes black chaff disease on barley (Hordeum vulgare). Genome data of this X. translucens type strain will improve our understanding of this bacterial species
Local text cohesion, reading ability and individual science aspirations: key factors influencing comprehension in science classes
In response to the concern of the need to improve the scientific skills of school children, this study
investigated the influence of text design (in terms of text cohesion) and individual differences, with
the aim of identifying pathways to improving science education in early secondary school (Key
Stage 3). One hundred and four secondary school children (56 females, 48 males), aged 12–13
years took part in the study. To assess the influence of local cohesion (lexical and grammatical links
between adjacent sentences) in science texts, we measured students’ comprehension (through multiple
choice questions) of science text that was high and low in local cohesion. To explore the role of
individual differences, students completed tests to measure general reading ability, general intelligence,
facets of conscientiousness, science self-concept and individual, friends and family aspirations
in science. Students were more accurate in answering comprehension questions after reading
text that was high in cohesion than low in cohesion, suggesting that high local text cohesion
improved students’ comprehension of science text. Reading ability predicted increased comprehension
for both text designs. Individual aspirations in science accounted for unique variance for comprehension
for high cohesion text. Implications for the teaching of secondary school science are
discussed
Engaging Struggling Adolescent Readers to Improve Reading Skills
This study examined the efficacy of a supplemental, multicomponent adolescent reading intervention for middle school students who scored below proficient on a state literacy assessment. Using a within-school experimental design, the authors randomly assigned 483 students in grades 6–8 to a business-as-usual control condition or to the Strategic Adolescent Reading Intervention (STARI), a supplemental reading program involving instruction to support word-reading skills, fluency, vocabulary, and comprehension, and peer talk to promote reading engagement and comprehension. The authors assessed behavioral engagement by measuring how much of the STARI curricular activities students completed during an academic school year, and collected intervention teachers' ratings of their students' reading engagement. STARI students outperformed control students on measures of word recognition (Cohen's d = 0.20), efficiency of basic reading comprehension (Cohen's d = 0.21), and morphological awareness (Cohen's d = 0.18). Reading engagement in its behavioral form, as measured by students' participation and involvement in the STARI curriculum, mediated the treatment effects on each of these three posttest outcomes. Intervention teachers' ratings of their students' emotional and cognitive engagement explained unique variance on reading posttests. Findings from this study support the hypothesis that (a) behavioral engagement fosters struggling adolescents' reading growth, and (b) teachers' perceptions of their students' emotional and cognitive engagement further contribute to reading competence
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