bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Characterization of High Impact Polystyrene from a Heterogeneous Styrene‐Rubber‐Polystyrene Solution: Influence of PS Concentration on the Phase Inversion, Morphology and Impact Strength
Authors: Soriano‐Corral Florentino , Morales Graciela , Acuña Pablo , Díaz‐Barriga Enrique , Arellano Berenice , Vargas Claribel , De la Paz Odilón 
Published: April 2013

AbstractHigh Impact Polystyrene (HIPS) was synthesized by free radical polymerization through the bulk‐bulk technique. Polybutadiene (PB) and/or poly(butadiene‐b‐styrene) copolymer (S:B = 30:70) (at 8 wt‐%) were used as impact modifiers in the presence of 0, 5 and 7.5 wt‐% of polystyrene (PS) and styrene monomer. The interval of phase inversion (PI) was determined through the evolution of melt flow index (MFI) and transmission electron microscopy (TEM), the conversion (X) and grafting degree (GD) were gravimetrically determined and impact strength (IS) tests were performed. When PS was added from the beginning of the reaction in the presence of SB rubber, the PI shifted to lower values of polymerization time (from 270 min in the reference HIPS to 190 min when 5 and 7.5 wt‐% of PS was added, respectively). The morphology of the reference HIPS was of the core shell type and in the case of adding PS the morphology at the PI changed to a quasi‐salami type, due to a poor stability of the system as a consequence of the low GD. The final size of the disperse phase increased 292 and 51% in the presence of PS and the volume fraction increased 100% yielding HIPS with an IS from 20 (reference HIPS) to 30J/m for 7.5 wt‐% of added PS.In the system with PB as the precursor rubber the salami structure in the reference HIPS, increased its size from 0.5 µm to 2.1 and 2.6 µm for 5 and 7.5 wt‐% of added PS, but instead of that, the IS remained without significant changes.
Full‐discrete finite element method for the stochastic elastic equation driven by additive noise
Authors: Qi Ruisheng , Yang Xiaoyuan , Zhang Yinghan 
Published: April 2013

AbstractWe study the full‐discrete finite element method for the stochastic elastic equation driven by additive noise. To analyze the error estimates, we write the stochastic elastic equation as an abstract stochastic equation. Strong convergence estimates in the root mean square L2 ‐norm are obtained by using the error estimates for the deterministic problem and the semigroup theory. Numerical experiments are carried out to verify the theoretical results. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Anti‐Yo mediated paraneoplastic cerebellar degeneration in the context of breast cancer: a case report and literature review
Authors: Key Richard Garrett , Root James C. 
Published: April 2013

AbstractBackgroundParaneoplastic syndromes are of interest to psycho‐oncologists because they may be misdiagnosed initially as primary psychiatric disorders and can have profound neuropsychiatric and psychosocial sequelae. Paraneoplastic cerebellar degeneration (PCD) is a paraneoplastic syndrome which destroys Purkinje cells of the cerebellum and causes trunk and limb ataxia, dysarthria, diplopia, and vertigo, which often precede the diagnosis of cancer. Anti‐Yo PCD is a devastating syndrome that significantly worsens prognosis in terms of functional ability and survival.MethodsWe present the case of a woman with progressive cerebellar deficits, which were misdiagnosed for several months before breast cancer and anti‐Yo antibodies were discovered.ResultsPCD may be misdiagnosed as a primary psychiatric disorder. Results of neuropsychological assessment in this case found subtle attentional dysfunction but relatively preserved cognitive functioning in other domains.DiscussionThe literature relating to PCD and psychiatric manifestations of cerebellar disease are reviewed. The limitations of our current understanding of non‐motor cerebellar function are highlighted, asserting the need for further study in this area. Copyright © 2013 John Wiley & Sons, Ltd.
Synthesis and Characterization of Urea Nitrate and Nitrourea
Authors: Oxley Jimmie C. , Smith James L. , Vadlamannati Sravanthi , Brown Austin C. , Zhang Guang , Swanson Devon S. , Canino Jonathan 
Published: April 2013

AbstractUrea nitrate (UN) has not found use as a legitimate explosive but is commonly used as an improvised explosive. The dehydration product of UN is nitrourea (NU). Visually both UN and NU are white solids that both melt around 160 °C. Other properties differ markedly as might be expected from an inorganic salt (UN) and an organic molecular compound (NU). An extensive physical characterization of NU and UN is reported. Two reported routes to the NU product are compared and a decomposition mechanism of UN proposed.
Breakup Time of Zirconium Shaped Charge Jet
Authors: Elshenawy T. , Li Qing Ming 
Published: April 2013

AbstractThe Johnson‐Cook parameters for the zirconium material were determined based on the data obtained from the tensile testing of zirconium specimens at different strain‐rates and different temperatures. The velocity difference (VPL) between the particulated jet fragments was calculated for zirconium liners of different thicknesses using Johnson‐Cook constitutive equation. A breakup time formula for the zirconium shaped charge was proposed, which demonstrated better ductility performance than the copper shaped charge.
Pre‐processing liquid chromatography/high‐resolution mass spectrometry data: extracting pure mass spectra by deconvolution from the invariance of isotopic distribution
Authors: Krishnan Shaji , Verheij Elwin E. R. , Bas Richard C. , Hendriks Margriet W. B. , Hankemeier Thomas , Thissen Uwe , Coulier Leon 
Published: April 2013

RATIONALEMass spectra obtained by deconvolution of liquid chromatography/high‐resolution mass spectrometry (LC/HRMS) data can be impaired by non‐informative mass‐over‐charge (m/z) channels. This impairment of mass spectra can have significant negative influence on further post‐processing, like quantification and identification.METHODSA metric derived from the knowledge of errors in isotopic distribution patterns, and quality of the signal within a pre‐defined mass chromatogram block, has been developed to pre‐select all informative m/z channels.RESULTSThis procedure results in the clean‐up of deconvoluted mass spectra by maintaining the intensity counts from m/z channels that originate from a specific compound/molecular ion, for example, molecular ion, adducts, 13C‐isotopes, multiply charged ions and removing all m/z channels that are not related to the specific peak. The methodology has been successfully demonstrated for two sets of high‐resolution LC/MS data.CONCLUSIONSThe approach described is therefore thought to be a useful tool in the automatic processing of LC/HRMS data. It clearly shows the advantages compared to other approaches like peak picking and de‐isotoping in the sense that all information is retained while non‐informative data is removed automatically. Copyright © 2013 John Wiley & Sons, Ltd.
Timing of isotopic integration in marine mammal skull: comparative study between calcified tissues
Authors: Riofrío‐Lazo Marjorie , Aurioles‐Gamboa David 
Published: April 2013

RATIONALETissues with different turnover rates have different isotope compositions and reflect the different periods in an animal's life when the isotopes are incorporated during the growth of tissues. Bone is one of the most used tissues for reconstruction of an animal's diet; however, the time of isotope integration remains unknown for many species.METHODSThe δ15N and δ13C values in tooth dentine and bone tissue from the maxilla and mandible of 21 stranded northern elephant seals, Mirounga angustirostris, collected on the San Benito and Magdalena Islands, Mexico, between 2000 and 2008 were compared. Bone and dentine samples from each growth layer within the tooth were analyzed using a PDZ Europa ANCA‐GSL elemental analyzer interfaced with a PDZ Europa 20‐20 continuous flow gas source mass spectrometer.RESULTSThe δ15N and δ13C values were not different between bone structures, indicating similar turnover rates, metabolic activity and amino acid compositions. The differences in the observed δ13C values between tissues are probably indicative of differences in their amino acid compositions, although the similarities in δ15N values indicated less variation from different amino acids. Correlation of the analyses between isotopic values of tissues suggests that the maxilla and/or mandible of M. angustirostris might reflect the δ15N signal incorporated during the last 5 years of life of the individuals.CONCLUSIONSThis study demonstrated the usefulness of the applied approach for providing a best approximation of the timing of isotopic integration into the skull of a marine mammal, thereby reducing uncertainty in exploring historic changes in the species' feeding behavior. Copyright © 2013 John Wiley & Sons, Ltd.
Conducting Talk in Secondary Science Classrooms: Investigating Instructional Moves and Teachers’ Beliefs
Authors: PIMENTEL DIANE SILVA , McNEILL KATHERINE L. 
Published: April 2013

ABSTRACTWhole‐class discussion is a common instructional approach used by secondary science teachers. When orchestrated well, such an approach can provide students with opportunities to engage in extensive science talk with the benefit of teacher guidance and feedback. Our study investigated teachers’ approaches to discussion during the piloting of an urban ecology curriculum designed to support student participation in science discourse as well as teachers’ beliefs about science talk. Participants included five secondary science teachers and their students (n = 116). Our analysis focused on transcripts of whole‐class discussions and interviews with teachers about their beliefs regarding talk. We found that the students’ contributions during discussions were typically limited to simple phrases or short sentence responses that did not voluntarily include reasoning. The teachers’ framing of the lessons and the moves the teachers made during the discussions seemed to reinforce the limited nature of the students’ responses. Furthermore, we found that teachers rarely used probing questions or tossed back students’ ideas. The beliefs teachers expressed about their students, themselves, and external factors provided insight into why teachers continued to take an authoritative stance even though they believed teacher‐driven discussion was not the ideal. © 2013Wiley Periodicals, Inc. Sci Ed 97:367–394, 2013
Ultrathin Calcium Silicate Hydrate Nanosheets with Large Specific Surface Areas: Synthesis, Crystallization, Layered Self‐Assembly and Applications as Excellent Adsorbents for Drug, Protein, and Metal Ions
Authors: Wu Jin , Zhu Ying‐Jie , Chen Feng 
Published: April 2013

AbstractA simple and low‐cost solution synthesis is reported for low‐crystalline 1.4 nm tobermorite‐like calcium silicate hydrate (CSH) ultrathin nanosheets with a thickness of ∼2.8 nm and with a large specific surface area (SSA), via a reaction‐rate‐controlled precipitation process. The BET SSA of the CSH ultrathin nanosheets can reach as high as 505 m2 g−1. The CSH ultrathin nanosheets have little cytotoxicity and can be converted to anhydrous calcium silicate (ACS) ultrathin nanosheets with a well preserved morphology via a heat treatment process. The crystallinity of CSH ultrathin nanosheets can be improved by solvothermal treatment in water/ethanol binary solvents or a single solvent of water, producing well‐crystalline 1.1 nm tobermorite‐like CSH nanobelts or nanosheets. CSH ultrathin nanosheets acting as building blocks can self‐assemble into layered nanostructures via three different routes. The CSH ultrathin nanosheets are investigated as promising adsorbents for protein (hemoglobin, Hb), drug (ibuprofen, IBU), and metal ions (Cr3+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+). The highest adsorbed percentages of Hb and IBU are found to be 83% and 94%, respectively. The highest adsorption capacities of Hb and IBU are found to be as high as 878 milligram Hb per gram CSH and 2.2 gram IBU per gram CSH, respectively. The ppm level metal ions can be totally adsorbed from aqueous solution in just a few minutes. Thus, the CSH ultrathin nanosheets are a promising candidate as excellent adsorbents in the biomedical field and for waste water treatment. Several empirical laws are summarized based on the adsorption profiles of Hb and IBU using CSH ultrathin nanosheets as the adsorbent. Furthermore, the ACS ultrathin nanosheets as adsorbents for Hb protein and IBU drug are investigated.
Teacher‐student relationships: A growing field of study
Authors: Bernstein‐Yamashiro Beth , Noam Gil G. 
Published: April 2013

AbstractA substantial percentage of students come to school with a number of stress factors from life circumstances, personal clinical attributes, and typical adolescent challenges. As a result, some students become disengaged from school, are unsuccessful, or drop out of school. School structures are not always equipped to respond to such problems. A mounting collection of research has begun to document the importance of teacher‐student relationships in academic success and socioemotional development. Much of this research reveals that relationships between teachers and students can make a vital difference in student success.
Learning together: Teaching, relationships, and teachers' work
Authors: Bernstein‐Yamashiro Beth , Noam Gil G. 
Published: April 2013

AbstractTeachers find that having close personal relationships with students is deeply rewarding in their work and that they contribute to more effective classrooms. The relationships, which many consider to be part and parcel of good teaching, afford teachers the opportunity to reach students intellectually and emotionally. Still, the relationships can be overwhelming and confusing for teachers. In interviews, teachers at a large and a small high school discuss how the relationships offer them both rewards and challenges in their work, their personal lives, and their efforts to humanize their classrooms.
Youth development practitioners and their relationships in schools and after‐school programs
Authors: Noam Gil G. , Bernstein‐Yamashiro Beth 
Published: April 2013

AbstractThis article examines the kinds of relationships that nonteacher educators, especially youth development practitioners working in after‐school settings, have with students. It addresses the fact that these adults in schools have an explicit youth‐oriented and relational approach, find out many productive and anxiety‐provoking facts about their students, and often do not have sufficient training and supervision to deal with the problems that emerge. It also examines the issue that the roles of these practitioners are varied and differ from the often very defined roles of other school personnel. The article divides the typical functions of the youth development practitioner into three main domains: educator, mentor, and connector.
The role of a student support system and the clinical consultant
Authors: Noam Gil G. , Bernstein‐Yamashiro Beth 
Published: April 2013

AbstractThis article addresses the fact that student–teacher relationships uncover many clinical issues, such as trauma. It looks at statistics of how prevalent mental health disorders and problems are and then shows that no teacher can handle all of the kinds of problems that will emerge in open relationships with the students. They need to do this work in the context of a productive student support team and system. The article provides a framework using the public health pyramid that can help organize schools. It ends by discussing the role of a consultant to teachers and the school to help with relationship binds, boundary transgressions, and dilemmas.
Working with teachers to develop healthy relationships with students
Authors: Bernstein‐Yamashiro Beth , Noam Gil G. 
Published: April 2013

AbstractThis article describes activities that can be used with multiple audiences of teachers, administrators, or other caregivers regarding setting boundaries in personal relationships with students. First, participants must think about and discuss relationships that they experienced with their own teachers in the past and determine what aspects of those relationships made an impression on them. In many cases, these connections deeply influenced teachers to join the profession. Second, participants consider dilemmas that they would realistically face with students and decide how they would respond. The dilemmas are derived from actual encounters teachers describe in this volume and elsewhere. In groups, they discuss what the ramifications might be in each circumstance and explore together sound and appropriate responses. Finally, there is an emphasis on the process of strategizing well before these dilemmas arise.
A dialogue between an educator and psychologist
Authors: Noam Gil G. , Bernstein‐Yamashiro Beth 
Published: April 2013

AbstractThis conclusion to the volume presents a dialogue from the perspective of educator and clinician. With examples from professional development and practice, the discussion revolves around teacher training and the role of the administrator in creating a bounded and safe environment in which teachers can develop healthy relationships. It discusses the kind of support teachers need from mental health professionals to grow, reduce the risk of burnout, and obtain help for students when necessary.
Dietary Intake and Food Sources of Total and Individual Polyunsaturated Fatty Acids in the Belgian Population Over 15 Years Old
Authors: Sioen Isabelle , Vyncke Krishna , De Maeyer Mieke , Gerichhausen Monique , De Henauw Stefaan 
Published: April 2013

AbstractAdvances in our knowledge of the physiological functions of dietary polyunsaturated fatty acids (PUFAs) have led to an increased interest in food sources and the level of dietary intake of these nutrients. Up to now, no representative data was available for the Belgian adult population. This study aimed to describe data on the intake and food sources of total and individual omega‐6 and omega‐3 PUFA for the Belgian population over 15 years old. PUFA intakes were assessed for 3,043 Belgian adults, based on two non‐consecutive 24 h recalls. Usual intakes were calculated using the multiple source method. The results showed that the intake of linoleic acid (LA) is in accordance with the recommendation for almost all Belgian adults. However, the intake of omega‐3 PUFA is suboptimal for a large part of the studied population and also the intake of total PUFA should be increased for a part of the population. The main food source of LA and α‐linolenic acid (ALA) was the group of fats and oils (60.6 % for LA and 53.1 % for ALA). Fish and fish products were the most important sources of long chain omega‐3 PUFA. Age influenced fatty acids intake, with higher intake of omega‐3 PUFA in the older age groups. To fill the gap between the intake and recommendation of total PUFA, and in particular omega‐3 PUFA, sustainable strategies and efficient consumer communication strategies will be needed.
Faculty and student perceptions of academic counselling services at an academic
health science center
Authors: Gaughf Natalie White , Smith Penni L. , Williams Dara A. 
Published: April 2013

There are limited data on support services that facilitate students’ academic
success at academic health science centres. The authors explored faculty and students’
perceptions of available academic counselling services (ACS) at an academic health
science centre in the Southeastern United States. Participants were surveyed in May and
June of 2011 regarding the ACS available at the institution. Fifty-nine percent of
faculty respondents (N = 471) agreed that academic counselling was a necessary part of
the institution, but only 26 % reported knowledge of how to refer students for academic
counselling. Only 18 % stated they had previously referred a student for services.
Fifty-four percent of student respondents (N = 360) agreed that academic counselling was
a necessary part of the institution and 60 % stated that they would seek these services
if needed. However, only 35 % of students reported that they were aware of how to access
the services. These findings suggest a discrepancy between the belief that academic
support services have value and their knowledge about how to utilize the services. It is
recommended that academic health science centres consider the promotion of available
academic support services amongst both faculty and students when designing and
implementing programmes to reduce this potential obstacle to service
utilization.
A dyadic reciprocity index for repeated interaction networks
Authors: WANG CHENG , LIZARDO OMAR , HACHEN DAVID , STRATHMAN ANTHONY , TOROCZKAI ZOLTÁN , CHAWLA NITESH V. 
Published: April 2013

AbstractA wide variety of networked systems in human societies are composed of repeated communications between actors. A dyadic relationship made up of repeated interactions may be reciprocal (both actors have the same probability of directing a communication attempt to the other) or non-reciprocal (one actor has a higher probability of initiating a communication attempt than the other). In this paper we propose a theoretically motivated index of reciprocity appropriate for networks formed from repeated interactions based on these probabilities. We go on to examine the distribution of reciprocity in a large-scale social network built from trace-logs of over a billion cell-phone communication events across millions of actors in a large industrialized country. We find that while most relationships tend toward reciprocity, a substantial minority of relationships exhibit large levels of non-reciprocity. This is puzzling because behavioral theories in social science predict that persons will selectively terminate non-reciprocal relationships, keeping only those that approach reciprocity. We point to two structural features of human communication behavior and relationship formation—the division of contacts into strong and weak ties and degree-based assortativity—that either help or hinder the ability of persons to obtain communicative balance in their relationships. We examine the extent to which deviations from reciprocity in the observed network are partially traceable to the operation of these countervailing tendencies.
Gravity's Rainbow: A dynamic latent space model for the world trade network
Authors: WARD MICHAEL D. , AHLQUIST JOHN S. , ROZENAS ARTURAS 
Published: April 2013

AbstractThe gravity model, long the empirical workhorse for modeling international trade, ignores network dependencies in bilateral trade data, instead assuming that dyadic trade is independent, conditional on a hierarchy of covariates over country, time, and dyad. We argue that there are theoretical as well as empirical reasons to expect network dependencies in international trade. Consequently, standard gravity models are empirically inadequate. We combine a gravity model specification with “latent space” networks to develop a dynamic mixture model for real-valued directed graphs. The model simultaneously incorporates network dependencies in both trade incidence and trade volumes. We estimate this model using bilateral trade data from 1990 to 2008. The model substantially outperforms standard accounts in terms of both in- and out-of-sample predictive heuristics. We illustrate the model's usefulness by tracking trading propensities between the USA and China.
What is network science?
Authors: BRANDES ULRIK , ROBINS GARRY , McCRANIE ANN , WASSERMAN STANLEY 
Published: April 2013

AbstractThis is the beginning of Network Science. The journal has been created because network science is exploding. As is typical for a field in formation, the discussions about its scope, contents, and foundations are intense. On these first few pages of the first issue of our new journal, we would like to share our own vision of the emerging science of networks.