bluuebunny/crossref_metadata_2025_split huggingface dataset:
Students' understanding of the nature and purpose of models
Authors: Gogolin Sarah , Krüger Dirk 
Published: March 2018

AbstractThe process of thinking in and about models as a scientific practice should be integrated into science teaching and learning. Empirical studies show that students see models primarily in their role as media to facilitate content learning while rarely appreciating models as instruments of scientists which allow the deduction and the testing of predictions. In order to foster students' meta‐modeling knowledge successfully, specific diagnostic information about students' understanding of models and modeling is needed. The aim of this study is to gather such diagnostic information by investigating students' understanding of the nature and the purpose of models in biology with respect to context‐ and grade‐specific differences. Students' understanding of the nature and the purpose of models was assessed by using forced choice tasks (Nstudents = 285). In order to gain qualitative insight into possible reasons for context‐specific differences, the students were additionally asked to give reason for their decision in the forced choice tasks by answering open‐ended justification tasks. The results indicate that the majority of students in all grades see models as idealized representations of an original which have the purpose to show or to describe this original. Students' levels of understanding of the nature and the purpose of models increase only little across grades. Nevertheless, a grade‐specific analysis of the consistency of students' understanding across contexts suggests that the students' understanding becomes more consistent in higher grades. Students' justifications helped to identify model contexts which have a high potential to be fruitful when trying to foster students' understanding of the nature and the purpose of models.
Learning progressions as tools for supporting teacher content knowledge and pedagogical content knowledge about water in environmental systems
Authors: Gunckel Kristin L. , Covitt Beth A. , Salinas Ivan 
Published: March 2018

AbstractResearch on learning progressions has led to advances in understanding student learning about big ideas in science, but teachers struggle to leverage the full potential of learning progressions for classroom instruction. Because learning progressions lay out how students' ideas change over a long period of time, learning progressions could help teachers build better understanding of student thinking, appropriate learning goals, and instructional moves for supporting students in developing more sophisticated ideas. In this study, we explored the potential of learning progression‐based curriculum materials to support teachers in developing more sophisticated content knowledge (CK) and pedagocial content knowledge (PCK) for teaching about water in environmental systems. Teachers participated in professional development that introduced them to a learning progression for water in environmental systems and curriculum materials based on this learning progression. Teachers completed written assessments of their CK and PCK prior to the workshops and a year later. Analyses showed that teachers who taught lessons using the learning progression‐based curriculum materials showed modest increases in CK, knowledge of learning goals, and knowledge of student thinking. These increases were greater than analogous changes evident for teachers who did not use the curriculum materials. However, even among those who implemented the curriculum materials, teachers' post‐assessment performance did not yet reflect knowledge for supporting students in developing model‐based reasoning about water. These results show that learning progressions have potential for supporting teacher learning, but that the ubiquity of traditional school science discourse may limit their potential for both student and teacher progress toward model‐based reasoning.
Localized tetanus treated with kampo medicines
Authors: Nakae Hajime , Satoh Kasumi , Okuyama Manabu , Furuya Tomoki 
Published: March 2018

ABSTRACTCaseA 73‐year‐old woman with a history of generalized tetanus and hypertension developed localized tetanus. Daisaikoto (DST) was used to control spasming of cervical muscles given the symptom of tenderness observed on both sides of her abdomen, kyokyo‐kuman. All symptoms except for cheek discomfort were improved. On day 7, shakuyakukanzoto (SKT) was given to control the residual symptoms.OutcomeResidual symptoms improved after treatment with DST and SKT.ConclusionDST can be used for the management of muscle spasms in localized tetanus, based on the oriental medical syndromes.
Books for Two Voices: Fluency Practice With Beginning Readers
Authors: Son Eun Hye , Chase Maggie 
Published: March 2018

AbstractThis article discusses how to implement paired reading with developing readers to foster students’ fluency and reading comprehension. The teacher first helps students comprehend the story with focused discussion questions and the completion of a beginning, middle, and end (B‐M‐E) chart. Then, the teacher scaffolds students to do the oral reading through modeling, guided practice, and independent practice. Students are encouraged to use a fluency self‐assessment rubric to reflect on their reading and think of ways to improve their reading. Once students are familiar with the routine, the teacher can set up a station with a variety of children's books where students can practice paired reading on their own. A bibliography of children's books is provided wherein the two main characters’ dialogue carries the majority of the story and font support is provided to aid in prosody.
Empowering Parents to Encourage Children to Read Beyond the Early Years
Authors: Merga Margaret K. , Mat Roni Saiyidi 
Published: March 2018

AbstractEnjoyment of reading books is related to reading proficiency, and fostering students’ enjoyment of reading is imperative to support continued reading engagement. However, not all students understand that reading is important, and not all students are regularly engaged in recreational reading. Children typically read for pleasure less often as they age, leading researchers to seek effective ways that social influences can support them to be lifelong readers beyond the early years. Parents can play an important role in communicating the continued importance of reading and fostering positive attitudes toward reading. However, after independent reading skill acquisition, parents may become a less potent encouraging and supportive force. The authors explore older students’ experiences of both independent and shared reading and their perception of parental support, involvement, and modeling to highlight potential roles that parental figures can play in reading beyond the early years.
Comparison of three commercially available placental growth factor‐based tests in women with suspected preterm pre‐eclampsia: the COMPARE study
Authors: McCarthy F. P. , Gill C. , Seed P. T. , Bramham K. , Chappell L. C. , Shennan A. H. 
Published: March 2018

ABSTRACTObjectiveTo compare the performance of three placental growth factor (PlGF)‐based tests in predicting delivery within 14 days from testing in women with suspected preterm pre‐eclampsia before 35 weeks' gestation.MethodsThis was a retrospective analysis of samples collected from three prospective pregnancy cohort studies. Participants were pregnant women with suspected preterm pre‐eclampsia recruited in tertiary maternity units in the UK and Ireland. Samples were analyzed simultaneously according to the manufacturers' directions. The tests compared were the DELFIA Xpress PlGF 1‐2‐3 test, the Triage PlGF test and the Elecsys immunoassay soluble fms‐like tyrosine kinase‐1 (sFlt‐1)/PlGF ratio. Areas under receiver–operating characteristics curves (AUCs) were compared. The main outcome measure was detection of a difference of 0.05 in AUC between tests for delivery within 14 days of testing.ResultsPlasma samples from 396 women and serum samples from 244 women were assayed. In predicting delivery within 14 days secondary to suspected pre‐eclampsia prior to 35 weeks' gestation, no significant differences were observed in AUCs (P = 0.795), sensitivities (P = 0.249), positive predictive values (P = 0.765) or negative predictive values (P = 0.920) between the three tests. The specificity of the Elecsys sFlt‐1/PlGF ratio test was higher than that of the other two tests (P < 0.001).ConclusionsThe tests perform similarly in their prediction of need for delivery within 14 days in women with suspected pre‐eclampsia. The high negative predictive values support the role of PlGF‐based tests as ‘rule‐out’ tests for pre‐eclampsia. © 2018 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Correlation between fetoplacental Doppler indices and measurements of cardiac function in term fetuses
Authors: Alsolai A. A. , Bligh L. N. , Greer R. M. , Kumar S. 
Published: March 2018

ABSTRACTObjectiveRedistribution of cardiac output (CO) is responsible for the brain‐sparing effect seen during periods of fetal stress. Our aim was to investigate prospectively the correlation between fetoplacental Doppler indices and measurements of cardiac function in uncomplicated term singleton pregnancy.MethodsThis was a prospective observational study of normotensive women with appropriately grown, non‐anomalous singleton pregnancy. Participants underwent fortnightly ultrasound examinations from 36 weeks' gestation until delivery, and intrapartum and neonatal outcomes were recorded. The correlation between fetoplacental Doppler indices and various measurements of cardiac function was evaluated.ResultsThe study cohort comprised 273 singleton pregnancies. The cerebroplacental ratio (CPR) was correlated positively with left ventricular CO (LVCO) (P < 0.001, rho = 0.29), left‐to‐right ventricular CO ratio (LVCO/RVCO; P < 0.001, rho = 0.41), global left ventricular strain (P < 0.01, rho = 0.17) and global right ventricular strain (P < 0.001, rho = 0.22). The CPR was correlated inversely with the left ventricular myocardial performance index (P < 0.01, rho = –0.18) and the RVCO (P < 0.001, rho = –0.28). The LVCO and global left ventricular strain were correlated positively with umbilical venous flow (P = 0.04, rho = 0.18 and P < 0.001, rho = 0.25, respectively). There was minimal or no correlation between either the mean uterine artery pulsatility index (PI) or umbilical artery PI with any cardiac indices.ConclusionThe fetal CPR, middle cerebral artery PI and umbilical venous flow are correlated positively with LVCO, LVCO/RVCO and global left ventricular strain in low‐risk term pregnancies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Sliding sign in third‐trimester sonographic evaluation of intra‐abdominal adhesions in women undergoing repeat Cesarean section: a novel technique
Authors: Baron J. , Tirosh D. , Mastrolia S. A. , Ben‐Haroush Y. , Schwartz S. , Kerner Y. , Hershkovitz R. 
Published: March 2018

ABSTRACTObjectiveIntra‐abdominal adhesions are associated with an increased risk of complications during repeat Cesarean section (CS), such as bladder and bowel injury, hemorrhage, infection and hysterectomy. We present a simple sonographic marker, the ‘sliding sign’ of the uterus, for the prediction of intra‐abdominal adhesions in the third trimester of pregnancy in women undergoing repeat CS.MethodsThis was a prospective observational study of pregnant women with a history of at least one Cesarean delivery evaluated by transabdominal ultrasound during the third trimester of an ongoing pregnancy. In order to diagnose intra‐abdominal adhesions, we assessed a sonographic sign, the sliding of the uterus under the inner part of the fascia of the abdominal muscles during deep breathing. Women were considered to be at high risk for severe adhesions if uterine sliding was absent and at low risk in the presence of obvious or moderate uterine sliding. A comparison between sonographic findings and intra‐abdominal adhesions observed during surgery was performed.ResultsOf the 63 patients with one or more previous CS examined, 59 completed the study and underwent CS at our institution. In 16 of the 19 cases assigned to the high‐risk group for severe adhesions due to absence of sliding of the uterus, the suspicion was confirmed at surgery. The prediction of low risk for adhesions was confirmed in 35 out of 40 patients. The sensitivity and specificity of the sliding sign in predicting presence of intra‐abdominal adhesions in women undergoing repeat CS were 76.2% and 92.1%, respectively. Inter‐ and intraobserver correlation using Cohen's kappa coefficient were 0.52 and 0.77, respectively.ConclusionOur data show that a simple sonographic sign might be able to discriminate between high and low risk for intra‐abdominal adhesions in patients with a history of Cesarean delivery. This technique may aid clinical decisions in patients undergoing repeat CS. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Groundwater‐quality hazards of methane leakage from hydrocarbon wells: A review of observational and numerical studies and four testable hypotheses
Authors: Rice Amy K. , Lackey Greg , Proctor James , Singha Kamini 
Published: March 2018

Methane leakage from hydrocarbon wells plays an important role in the groundwater‐quality impacts of hydrocarbon development and presents a more likely hazard than hydraulic fracturing or formation fluids. Methane released from contaminated water wells has been linked with combustion risks and degraded water quality. Potentially, methane can serve as a precursor to other fluids associated with hydrocarbon extraction, such as volatile organics. In this review, we surveyed studies relating to contamination of drinking‐water aquifers by methane gas from leaking hydrocarbon wells. Challenges associated with linking methane in groundwater to hydrocarbon extraction are identified, highlighting the need for groundwater‐quality and well‐integrity databases. Science‐based policy recommendations are made, including deeper surface casings and greater cement coverage for wells with deviated wellbores, remediation of faulty abandoned wells, and increased gas‐migration monitoring. We suggest four hypotheses to quantify risks to groundwater quality from methane leakage. First, differentiation between thermogenic methane occurring in groundwater due to natural migration and thermogenic methane present due to hydrocarbon development can be used to alleviate the need for baseline measurements of methane in groundwater. Second, methane newly discovered in freshwater aquifers is unlikely to have originated from leaks beginning decades ago. Third, pertaining to the zone separating methane leakage from groundwater, relative permeability will have a larger impact on plume diameter than heterogeneity in intrinsic permeability. Fourth, thermogenic methane in groundwater will serve as a precursor to benzene, toluene, ethybenzene, and xylene (BTEX) under conditions where methane and BTEX coexist in a hydrocarbon reservoir and leakage is transported primarily in the aqueous phase.This article is categorized under:

Engineering Water > Sustainable Engineering of Water
Science of Water > Water Quality
Facing the urban overheating: Recent developments. Mitigation potential and sensitivity of the main technologies
Authors: Pisello Anna Laura , Saliari Maria , Vasilakopoulou Konstantina , Hadad Shamila , Santamouris Mattheos 
Published: March 2018

Urban overheating represents an internationally acknowledged anthropogenic phenomenon related to climate change and to the massive shift of population worldwide toward urban areas, which are increasingly enlarging their size and density. The consequences of this urban warming (i.e., urban heat island) may compromise citizens’ quality of life in urban areas, indoor and outdoor comfort perception, and building energy performance in summer conditions. In this panorama, this review presents recent contributions demonstrating the effectiveness and urgent need of existing mitigation strategies. The same strategies are also comparatively assessed by means of a sensitivity analysis demonstrating their effect with varying climate conditions and urban context. Results of existing studies, validated by the present assessment, aimed at quantitatively investigating the effect of mitigation strategies for reducing building cooling needs and enhancing urban well‐being, thanks to international scientific effort carried out in the last decades. To this aim, the logical flow of the review deals with the main technologies for urban warming mitigation are described, together with the main findings of numerical and experimental research initiatives, demonstrating the field effect of improving pedestrians comfort and urban well‐being all around the world. Then, the mitigation potential of key green, water and cool strategies is critically reviewed, and further scientific and implementation needs are discussed. All the reviewed contributions demonstrate an undeniable technology readiness level for their practical implementation and highlight the true necessity of a shared and synergistic policy effort worldwide.This article is categorized under:

Energy and Urban Design > Systems and Infrastructure
Concentrating Solar Power > Climate and Environment
Energy Efficiency > Climate and Environment
Renewable energy auctions in sub‐Saharan Africa: Comparing the South African, Ugandan, and Zambian Programs
Authors: Kruger Wikus , Eberhard Anton 
Published: March 2018

Sub‐Saharan Africa desperately needs more electricity. Recent years have seen private investment in renewable energy projects breaking through in the region, primarily driven by well‐designed and implemented auction programs. We review three renewable energy auction programs in the region to improve our understanding of the auction design and implementation elements that have enabled this important transition: the South African Renewable Energy Independent Power Producers Procurement Program (REIPPPP); the GET FiT solar facility in Uganda; and the first round of the Scaling Solar program in Zambia. Our analysis shows that a well‐designed and implemented program that adequately deals with risks for both the procuring authorities and investors is able to deliver good investment and price outcomes in sub‐Saharan Africa.This article is categorized under:

Photovoltaics > Climate and Environment
Energy Policy and Planning > Climate and Environment
Photovoltaics > Economics and Policy
Energy Policy and Planning > Economics and Policy
Constructing support vector machines with missing data
Authors: Stewart Thomas G. , Zeng Donglin , Wu Michael C. 
Published: March 2018

Support vector machine (SVM) classification is a statistical learning method which easily accommodates large numbers of predictors and can discover both linear and nonlinear relationships between the predictors and outcomes. A common challenge is constructing an SVM when the training set includes observations with missing predictor values. In this paper, we identify when missing data can bias an SVM classifier. Because the missing data mechanisms which bias SVMs differ from the traditional framework of missing‐at‐random and missing‐not‐at‐random, we argue for an SVM‐specific framework for understanding missing data. Furthermore, we compare a number of missing data strategies for SVMs in a simulation study and real data example, and we make recommendations for SVM users based on the simulation study.This article is categorized under:
Applications of Computational Statistics > Computational Mathematics
Statistical Learning and Exploratory Methods of the Data Sciences > Support Vector Machines
Estimation and testing for separable variance–covariance structures
Authors: Dutilleul Pierre 
Published: March 2018

The statistical analysis of data for a p‐variate response observed repeatedly on q occasions or of spatiotemporal data recorded at p locations by q times for n individuals may require that constraints be imposed on the modeling of the variance–covariance structure of the underlying process, not because of the repeated‐measures or spatiotemporal nature of the data but because there is not enough data otherwise to estimate the model parameters. Besides stationarity and isotropy, separability is an interesting option for that purpose because it reduces the number of variance‐covariance parameters to estimate, from pq(pq + 1)/2 to the Kronecker product of two matrices with p(p + 1)/2 and q(q + 1)/2 parameters. Originally, in the late 1980s, separability of the variance–covariance structure was assumed. Under this model, combined with the normality assumption on the underlying distribution, novel theoretical developments were thus made. The question of estimation of the parameters of a separable variance–covariance structure, more particularly by maximum likelihood, was raised from the early 1990s on, the question of testing for this structure being effectively addressed several years later. The existence and uniqueness of maximum likelihood estimators for the matrix normal distribution (i.e., the doubly multivariate normal distribution characterized by a simply separable variance–covariance structure) have been and remain questions of interest, as shown by recent results. Below, the reader is guided throughout the field of study of the separable variance–covariance structures as the author provides a fair treatment of the topic, its components, extensions (e.g., double separability), and future perspectives.This article is categorized under

Statistical and Graphical Methods of Data Analysis > Multivariate Analysis
Statistical and Graphical Methods of Data Analysis > Analysis of High Dimensional Data
Statistical and Graphical Methods of Data Analysis > Modeling Methods and Algorithms
In defense of Pratt's variable importance axioms: A response to Gromping
Authors: Thomas D. Roland , Kwan Ernest , Zumbo Bruno D. 
Published: March 2018

In a recent paper Gromping provided a wide‐ranging review of metrics for assessing variable importance in regression analysis. There are, however, several flaws in Gromping's criticism of the well‐known metric attributed to Pratt. Among the metrics she reviewed, Pratt's metric stands out because it is the only one that provides both a theoretically based definition of variable importance, and a simple method of estimation and inference. Our response is an effort to re‐evaluate this unique metric. We give a simplified and abbreviated account of Pratt's original derivation, based on which we address the flaws in Gromping's presentation. We also discuss heuristic interpretations of Pratt's metric, and suggest a new approach for selecting one from among the many available metrics for assessing importance. This approach is intended to supplement that suggested by Gromping. Accordingly, the goal of this response is to help practitioners better understand and choose between available metrics for assessing variable importance.This article is categorized under:
Statistical and Graphical Methods of Data Analysis > Multivariate Analysis
Statistical Learning and Exploratory Methods of the Data Sciences > Exploratory Data Analysis