bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elucidation of electron ionization mass spectrometric fragmentation pathways of trimethylsilyl ether derivatives of vicinal diols deriving from haplamine by collision‐induced dissociation gas chromatography/tandem mass spectrometry and 18O labelling
Authors: Ea Sompheary , Aubert Claude , Rontani Jean‐François , Teral Yannick , Campredon Mylène 
Published: March 2014

RATIONALEFormation of vicinal diols was observed after in vitro and in vivo studies of the natural product haplamine (9‐methoxy‐2,2‐dimethyl‐2,6‐dihydropyrano[3,2‐c]quinolin‐5‐one). These compounds, identified as trans‐ and cis‐3,4‐dihydroxy‐9‐methoxy‐2,2‐dimethyl‐2,3,4,6‐tetrahydropyrano[3,2‐c]quinolin‐5‐ones and trans‐ and cis‐3,4,9‐trihydroxy‐2,2‐dimethyl‐2,3,4,6‐tetrahydropyrano[3,2‐c]quinolin‐5‐ones, have a potential interest in oncology. It is therefore essential to elucidate their electron ionization mass spectrometric (EIMS) fragmentation pathways.METHODSEIMS fragmentation pathways of trimethylsilyl (TMS) derivatives of 3,4‐dihydroxy‐ and 3,4,9‐trihydroxyhaplamines were investigated. These pathways have been substantiated by: (i) comparison with EI mass spectra of structural homologues (silylated diols obtained from various chromenes and 1,2‐dihydronaphthalene), (ii) low‐energy collision‐induced dissociation (CID) gas chromatography/tandem mass spectrometry (GC/MS/MS) and (iii) 18O labelling.RESULTSCID‐MS/MS analyses and 18O labelling demonstrated that EI mass spectral fragmentation of these TMS derivatives involves a transannular cleavage of the pyran ring with formation of a characteristic intense cyclic ion. The study of the mass spectra of TMS derivatives of different chromenes and 1,2‐dihydroxynaphthalene allowed to confirm the proposed fragmentation pathways and to show that they act only when the pyran ring is present.CONCLUSIONSElimination of the neutral element [(CH3)2=C(H)OSi(CH3)3] and formation of cyclic ions play a key role during EI mass spectral fragmentation of the TMS derivatives of 3,4‐dihydroxy‐ and 3,4,9‐trihydroxyhaplamines. These fragmentation pathways could be generalized to TMS derivatives of cyclic compounds possessing vicinal diols close to a pyran ring. Copyright © 2014 John Wiley & Sons, Ltd.
A mixture of transition models for heterogeneous longitudinal ordinal data: with applications to longitudinal bacterial vaginosis data
Authors: Cheon Kyeongmi , Thoma Marie E. , Kong Xiangrong , Albert Paul S. 
Published: March 2014

AbstractMarkov models used to analyze transition patterns in discrete longitudinal data are based on the limiting assumption that individuals follow the common underlying transition process. However, when one is interested in diseases with different disease or severity subtypes, explicitly modeling subpopulation‐specific transition patterns may be appropriate. We propose a model which captures heterogeneity in the transition process through a finite mixture model formulation and provides a framework for identifying subpopulations at different risks. We apply the procedure to longitudinal bacterial vaginosis study data and demonstrate that the model fits the data well. Further, we show that under the mixture model formulation, we can make the important distinction between how covariates affect transition patterns unique to each of the subpopulations and how they affect which subgroup a participant will belong to. Practically, covariate effects on subpopulation‐specific transition behavior and those on subpopulation membership can be interpreted as effects on short‐term and long‐term transition behavior. We further investigate models with higher‐order subpopulation‐specific transition dependence. Copyright © 2014 John Wiley & Sons, Ltd.
Pax3 and Tbx5 Specify Whether PDGFRα+ Cells Assume Skeletal or Cardiac Muscle Fate in Differentiating Embryonic Stem Cells
Authors: Magli Alessandro , Schnettler Erin , Swanson Scott A. , Borges Luciene , Hoffman Kirsta , Stewart Ron , Thomson James A. , Keirstead Susan A. , Perlingeiro Rita C. R. 
Published: March 2014

Abstract
Embryonic stem cells (ESCs) represent an ideal model to study how lineage decisions are established during embryonic development. Using a doxycycline-inducible mouse ESC line, we have previously shown that expression of the transcriptional activator Pax3 in early mesodermal cells leads to the robust generation of paraxial mesoderm progenitors that ultimately differentiate into skeletal muscle precursors. Here, we show that the ability of this transcription factor to induce the skeletal myogenic cell fate occurs at the expenses of the cardiac lineage. Our results show that the PDGFRα+FLK1− subfraction represents the main population affected by Pax3, through downregulation of several transcripts encoding for proteins involved in cardiac development. We demonstrate that although Nkx2–5, Tbx5, and Gata4 negatively affect Pax3 skeletal myogenic activity, the cardiac potential of embryoid body-derived cultures is restored solely by forced expression of Tbx5. Taking advantage of this model, we used an unbiased genome-wide approach to identify genes whose expression is rescued by Tbx5, and which could represent important regulators of cardiac development. These findings elucidate mechanisms regulating the commitment of mesodermal cells in the early embryo and identify the Tbx5 cardiac transcriptome. Stem Cells 2014;32:2072–2083
Case‐based instruction: Improving students' conceptual understanding through cases in a mechanical engineering course
Authors: Yadav Aman , Vinh Megan , Shaver Gregory M. , Meckl Peter , Firebaugh Stephanie 
Published: March 2014

AbstractRecently, there has been a push within engineering curricula to adopt more learner‐centered pedagogies, such as case‐based instruction. Case‐based instruction has been hypothesized to make the curriculum more relevant and motivating for students by pushing them to integrate the concepts they have learned with other experiences. The current study examined the influence of case‐based instruction when compared to traditional lecture‐based instruction within a mechanical engineering course on student performance in terms of learning, conceptual understanding, and student perceptions towards the two approaches. Seventy students from one systems course in a mechanical engineering program participated in this study. The study utilized within subjects posttest only experimental research design to assess student learning and engagement from cases. Participants completed posttests and a survey. We found that students' conceptual understanding was significantly higher when learning from case‐based instruction as compared to traditional lecture. Additionally, the survey results exhibited that cases allowed for significantly more engagement and connections to the real world. However, students reported that cases were not better in improving their learning. Given limited research on the effectiveness of case‐based instruction in engineering, this study provides empirical support for the use of cases in engineering. We also argue that student perceptions are not accurate predictors for their actual learning outcomes. Implications for engineering educators and directions for future research are offered. © 2014 Wiley Periodicals, Inc. J Res Sci Teach 51: 659–677, 2014
Best Practices in Reading
Authors: Roskos Kathleen , Neuman Susan B. 
Published: March 2014

AbstractFor years, the field of reading education has been engaged in thinking about best practices. In this column we highlight a set of practices that have amassed a significant body of work to demonstrate their usefulness in improving children's motivation for learning to read, proficiency in reading, and their likelihood to become lifelong readers and writers. Explicit instruction in vocabulary, rereading and using digital textbooks to motivate children's reading are among some of these updated best practices. Those in the reading community are urged to consider best practices, and how we may promote their uses, with high fidelity in classroom instruction.
Leader, Teacher, Diagnostician, Colleague, and Change Agent
Authors: Galloway Emily Phillips , Lesaux Nonie K. 
Published: March 2014

AbstractReading specialists are conceptualized as instrumental to literacy reform efforts focused on data‐driven instruction and improvement of reading outcomes at all levels. But this has meant a real shift in their role. To keep pace with these changes in the literacy reform movement, in contrast to even 10 years ago, the role of the reading specialist is now outlined as both an educator of students and of teachers. Because the last comprehensive review occurred in 2001, we have attempted to synthesize, for the field, what is known about the daily work of today's reading specialist.
An energy‐efficient utility‐based distributed data routing scheme for heterogenous sensor networks
Authors: Behzadan Afshin , Anpalagan Alagan , Woungang Isaac , Ma Bobby , Chao Han‐Chieh 
Published: March 2014

AbstractA utility‐based distributed data routing algorithm is proposed and evaluated for heterogeneous wireless sensor networks. It is energy efficient and is based on a game‐theoretic heuristic load‐balancing approach. It runs on a hierarchical graph arranged as a tree with parents and children. Sensor nodes are considered heterogeneous in terms of their generated traffic, residual energy and data transmission rate and the bandwidth they provide to their children for communication. The proposed method generates a data routing tree in which child nodes are joined to parent nodes in an energy‐efficient way. The principles of the Stackelberg game, in which parents as leaders and children as followers, are used to support the distributive nature of sensor networks. In this context, parents behave cooperatively and help other parents to adjust their loads, while children act selfishly. Simulation results indicate the proposed method can produce on average more load‐balanced trees, resulting in over 30% longer network lifetime compared with the cumulative algorithm proposed in the literature. Copyright © 2014 John Wiley & Sons, Ltd.
Exploiting temporal and spatial diversities for spectrum sensing and access in cognitive vehicular networks
Authors: Liu Yi , Xie Shengli , Yu Rong , Zhang Yan , Zhang Xi , Yuen Chau 
Published: March 2014

AbstractIn cognitive vehicular networks (CVNs), spectrum sensing and access are introduced as the promising technologies to fully exploit the underutilized licensed spectrum. Because the sensing ability of a single secondary vehicular user (SVU) is affected by high mobility, dynamic topology, and unreliable wireless environment, collaborative sensing is developed to increase the sensing accuracy and efficiency. Generally, the synchronization is required in the collaborative sensing in CVN. However, it is difficult to keep all SVUs synchronized with others for sensing under the high dynamic network topology, and the sensing overhead of the synchronous cooperative action may be significant. In this paper, we first propose an asynchronous cooperative sensing scheme in which each SVU provides an energy information (EI) that is tagged with location and time information. The sensing decision will be made on account of the EI. Considering the temporal and spatial diversities of each SVU, we assign different weights to each EI and formulate the probabilities of detection and false alarm as the optimization problems to find the optimal weight of each EI. Then, based on the asynchronous sensing, the specifications of the opportunistic spectrum access mechanism are elaborated in both centralized and decentralized CVNs for the sake of practical implementation. We analyze the system performance in terms of achievable throughput and transmission delay. Numerical results show that the proposed scheme is able to achieve substantially higher throughput and lower delay, as compared with existing schemes. Copyright © 2014 John Wiley & Sons, Ltd.
Revisiting domain‐general accounts of category specificity in mind and brain
Authors: Chen Lang , Rogers Timothy T. 
Published: March 2014

Theories about the neural basis of semantic knowledge have been strongly influenced by reports that particular semantic categories can be differentially impaired by neuropathology and can differentially activate particular regions of cortex in brain imaging studies. One well‐known interpretation of these data is that the brain has evolved distinct functional and anatomical modules for storing and retrieving knowledge about different kinds of things. We review the evidence supporting an alternative view: that category specificity arises from many heterogeneous factors and so tells us little directly about the cognitive and neural architecture of semantic memory. We consider four general hypotheses about domain‐general causes of category‐specific patterns, their roots in early work, and their reemergence in contemporary research. We argue that there is compelling evidence supporting each hypothesis, and that the different hypotheses together can explain most of the interesting data. We further suggest that such a multifactor domain‐general approach to category specificity is appealing partly because it explains the important findings with reference to theoretical claims that are already widely accepted, and partly because it resolves several puzzles that arise under the alternative view.This article is categorized under:

Psychology > Language
Psychology > Memory
Neuroscience > Cognition
Human diet and cognition
Authors: Stevenson Richard J. , Prescott John 
Published: March 2014

Cognition influences what, when and how much we eat, which in turn affects the brain and hence cognition. In this overview, focusing mainly on the human literature, we start by examining cognitive influences on food and eating. This includes food preferences and choices (e.g., effects of learning, advertising, and cultural taboos), food habits relating to when and how much to eat (e.g., the concept of meals, dieting, and hunger strikes), the perception of food (e.g., the influence of appearance, food labels, and conceptions of naturalness), and how food perception is influenced by expertise. We also review how these various influences are disrupted by abnormalities of cognition (e.g., Gourmand syndrome, amnesia, and anorexia nervosa). The second part of the overview focuses on how diet affects cognition. We start by looking at the acute effects of diet, notably the impact of breakfast on cognitive performance in children. This is followed by a review of the effects of extended dietary exposures—years and lifetimes of particular diets. Here we look at the impacts of protein‐energy malnourishment and Western‐style diets, and their different, but adverse affects on cognition, and the beneficial effects on cognition of breast‐feeding and certain dietary practices. We then outline how diet and cooking may have allowed the evolution of the large energy‐hungry human brain. This overview serves to illustrate the multiple interactions that exist between cognition and diet, their importance to health and disease, and their impact on thinking about the role of conscious processes in decision making. WIREs Cogn Sci 2014, 5:463‐475. doi: 10.1002/wcs.1290This article is categorized under:

Psychology > Emotion and Motivation
Psychology > Perception and Psychophysics
Psychology > Reasoning and Decision Making
Effect of O‐ and Mn‐Doping on Superconductivity in FeTe0.5Se0.5 Superconductor
Authors: Thakur Gohil S. , Haque Zeba , Neha Prakriti , Gupta Laxmi C. , Patnaik Satyabrata , Ganguli Ashok K. 
Published: March 2014

AbstractThe effect of oxygen substitution at the selenium site and manganese substitution at the iron site in FeTe0.5Se0.5 superconductor was investigated. It was found that upon partial O substitution, Tc marginally decreases as seen in both resistivity and magnetization experiments. Tc decreases even by a small amount of oxygen concentration (as low as 1 %). This observation is in contrast against an earlier work on Fe(Te/Se) samples,1 wherein Tc as well as superconducting volume fraction were reported to increase in the samples annealed in air. Mn‐doping leads to a decrease in Tc in FeTe0.5Se0.5, which one would expect considering pair‐breaking due to Mn2+‐ions.
Structure and Properties of New Gallium‐containing Polyoxotungstates with Hexanuclear and Tetranuclear Cores
Authors: von Allmen Kim , Car Pierre‐Emmanuel , Blacque Olivier , Fox Thomas , Müller Rafael , Patzke Greta R. 
Published: March 2014

AbstractA series of new gallium‐containing silicotungstates was obtained from the one step reaction of the lacunary Na10[α‐SiW9O34]·15H2O Keggin‐type building block (SiW9) with gallium nitrate in aqueous solution. The sandwich‐type polyoxotungstate [Ga6(H2O)x{α‐SiW9O34(OH)y}2]n– (1) crystallizes first as a mixture of two similar polyoxometalates (1a and 1b), while [Ga4(H2O)2{α‐SiW10O38}2]12– (2) is generated from the mother liquor in a second step. Both newly obtained polyoxometalates with tetra‐ and hexanuclear gallium cores were structurally characterized with a wide range of methods encompassing single crystal and powder X‐ray diffraction techniques, FT‐IR spectroscopy, and thermal analysis. The solution stability of both dimeric POMs K10[Ga6(H2O)3{α‐SiW9O35(OH)2}2]·35.5H2O (1a) and K12[Ga4(H2O)2{α‐SiW10O38}2]·30H2O (2) was investigated with 183W NMR and HR ESI mass spectrometry, and the electrochemical properties of both compounds were determined by cyclic voltammetry.
Self‐assembly of Two 2D Copper(II) Coordination Networks with Tetrachloro‐1,3‐benzenedicarboxylate: Solvent Effects, Supramolecular Interactions, and Luminescence Behavior
Authors: Chen Sheng‐Chun , Wang Xin‐Xin , Luo Hai‐Kun , He Ming‐Yang , Li Cheng‐Peng , Chen Qun 
Published: March 2014

AbstractReaction of the rigid ligand 2,4,5,6‐tetrachloro‐1,3‐benzenedicarboxylic acid (1,3‐H2BDC‐Cl4) with copper(II) nitrate in different solvent systems afforded two new complexes {[Cu(1,3‐BDC‐Cl4)(DMF)] (H2O)}n (1) and {[Cu(1,3‐BDC‐Cl4)(H2O)3] (dioxane)·(H2O)}n (2), which were fully characterized by elemental analysis, IR spectroscopy, as well as single crystal and powder X‐ray diffiraction techniques. Single‐crystal X‐ray diffraction reveals that complexes 1 and 2 crystallize in different space groups P21/m and Pbca, respectivly. Compound 1 shows a two‐dimensional (2D) (4,6)‐connected layered network constructed by the connectivity between one‐dimensional (1D) [–Cu–DMF–COO–]n chains and tetrachlorinated backbones of 1,3‐BDC‐Cl4, which is further assembled to generate a three‐dimensional (3D) supramolecular framework through intermolecular O–H···O and O–H···Cl hydrogen‐bonding interactions. Compound 2 features a 2D 4‐connected sql coordination net formed by 1D [Cu‐H2O]n chains and 1,3‐BDC‐Cl4 spacers, which is further extended into a 3D supramolecular network by multiple O–H···O hydrogen‐bonding interactions. The different structural features of the two compounds suggest that the choice of solvent systems should play a key role in the process of assembly. Their thermal and fluorescence properties were also investigated.
Functional expression of a single-chain antibody fragment against human epidermal growth factor receptor 2 (HER2) inEscherichia coli
Authors: Akbari Vajihe , Mir Mohammad Sadeghi Hamid , Jafrian-Dehkordi Abbas , Abedi Daryoush , Chou C Perry 
Published: March 2014

AbstractThe human epidermal growth factor receptor (HER) family plays an important role in cell growth and signaling and alteration of its function has been demonstrated in many different kinds of cancer. Receptor dimerization is necessary for the HER signal transduction pathway and tyrosine kinase activity. Recently, several monoclonal antibodies have been developed to directly interfere with ligand–HER receptor binding and receptor dimerization. A single chain variable fragment (ScFv) is a valuable alternative to an intact antibody. This report describes the production and purification of an ScFv specific for domain II of the HER2 receptor in Escherichia coli BL21 (DE3) cytoplasm. The majority of expressed of anti-her2his-ScFv protein was produced as inclusion bodies. A Ni-NTA affinity column was used to purify the anti-her2his-ScFv protein. The molecular weight of anti-her2his-ScFv protein was estimated to be approximately 27 kDa, as confirmed by SDS-PAGE and Western blotting assay. The anti-her2his-ScFv showed near 95 % purity and reached a yield of approximately 29 mg/l in flask fermentation. The purified anti-her2his-ScFv showed its biological activity by binding to HER2 receptor on the surface of BT-474 cells. This ScFv may be a potential pharmaceutical candidate for targeting tumour cells overexpressing HER2 receptor.
Lipid Content and Fatty Acid Profile of Muscle, Brain and Eyes of Seven Freshwater Fish: a Comparative Study
Authors: Hong Hui , Zhou Yadi , Wu Hua , Luo Yongkang , Shen Huixing 
Published: March 2014

AbstractThe fatty acid and lipid content of the eyes, brain and muscle were determined for the following seven freshwater fish species in China: black carp, grass carp, silver carp, bighead carp, common carp, crucian carp, and Wuchang bream. Lipid contents of all seven freshwater fish were in the order of brain > eyes > muscle. Most of the freshwater fish demonstrated much lower n‐3 PUFA than n‐6 PUFA in all tissues with n‐3/n‐6 ratios varying between 0.07 and 0.40, while silver carp and bighead carp had much higher n‐3 PUFA than n‐6 PUFA. The percentage of PUFA in the muscle of all species are the highest compared to those of the eyes and brain, while no significant difference was observed in PUFA concentration between eyes and brain (p > 0.05). Multivariable analyses indicate that the fatty acid composition of the filter‐feeder fish (silver carp and bighead carp) was distinct from the other four species.
Optimal seed water content and storage temperature for preservation of Populus nigra L. germplasm
Authors: Suszka Jan , Plitta Beata P. , Michalak Marcin , Bujarska-Borkowska Barbara , Tylkowski Tadeusz , Chmielarz Paweł 
Published: March 2014

Abstract

Context

Black poplar (Populus nigra L.) is an alluvial forest tree species whose genetic pool is decreasing in Europe. Poplar trees produce short-lived seeds that do not store well.

Aim

The feasibility of seed storage in conventional and cryogenic conditions after their desiccation from water content (WC) of 0.15 to 0.07 g H2O g−1 dry mass (g g−1) was investigated.

Methods

Seed germinability was evaluated (seeds with a radicle and green cotyledons were counted) after storage of seeds for a period of 3 to 24 months at different temperatures: 20°, 10°, 3°, −3°, −10°, −20° or −196°C.

Results

Seeds desiccated to a 0.07 g g−1 WC can be stored successfully at −10 °C and −20 °C for at least 2 years. A significant decrease in germination was observed only after 12 months of seed storage (WC 0.15 g g−1) at temperatures above 0 °C. We demonstrated that both fresh (0.15 g g−1 WC) and desiccated (0.07 g g−1 WC) seeds can be preserved at −196 °C for at least 2 years.

Conclusions

Seed storage temperature and time of storage were statistically significant factors affecting seed storability. The presented data provide a foundation for the successful gene banking of P. nigra seeds.
Organisation und Versorgungsqualität
Authors: Kockert Svenja , Schott Thomas 
Published: March 2014

Einleitung
Gesundheit entsteht durch Kooperation zwischen Patient und den Behandlern. Dass diese Kooperation entscheidend durch den organisationsbezogenen Kontext geprägt ist, bleibt jedoch häufig unberücksichtigt. Insbesondere das Sozialkapital von Versorgungseinrichtungen scheint nach theoretischen Überlegungen ein wesentlicher Erfolgsfaktor darzustellen. Organisationale Rahmenbedingungen und das organisationale Verhalten sollten in der Versorgungsforschung zunehmend Aufmerksamkeit erfahren, um eine hohe Qualität der gesundheitlichen Versorgung sicherstellen zu können.