bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparison of navigators, snap‐shot field monitoring, and probe‐based field model training for correcting B0‐induced artifacts in ‐weighted images at 7 T
Authors: Wezel Joep , Boer Vincent O. , van der Velden Tijl A. , Webb Andrew G. , Klomp Dennis W.J. , Versluis Maarten J. , van Osch Matthias J.P. , Garpebring Anders 
Published: November 2016

PurposeTo compare methods for estimating B0 maps used in retrospective correction of high‐resolution anatomical images at ultra‐high field strength. The B0 maps were obtained using three methods: (1) 1D navigators and coil sensitivities, (2) field probe (FP) data and a low‐order spherical harmonics model, and (3) FP data and a training‐based model.MethodsData from nine subjects were acquired while they performed activities inducing B0 field fluctuations. Estimated B0 fields were compared with reference data, and the reductions of artifacts were compared in corrected
images.ResultsReduction of sum‐of‐squares difference relative to a reference image was evaluated, and Method 1 yielded the largest artifact reduction: 27 ± 15%, 20 ± 18% (mean ± 1 standard deviation) for deep breathing and combined deep breathing and hand motion activities. Method 3 performed almost as well (24 ± 18%, 15 ± 17%), provided that adequate training data were used, and Method 2 gave a similar result (21 ± 16%, 19 ± 17%).ConclusionThis study confirms that all of the investigated methods can be used in retrospective image correction. In terms of image quality, Method 1 had a small advantage, whereas the FP‐based methods measured the B0 field slightly more accurately. The specific strengths and weaknesses of FPs and navigators should therefore be considered when determining which B0‐estimation method to use. Magn Reson Med 78:1373–1382, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
On the accurate analysis of vibroacoustics in head insert gradient coils
Authors: Winkler Simone A. , Alejski Andrew , Wade Trevor , McKenzie Charles A. , Rutt Brian K. 
Published: November 2016

PurposeTo accurately analyze vibroacoustics in MR head gradient coils.Theory and MethodsA detailed theoretical model for gradient coil vibroacoustics, including the first description and modeling of Lorentz damping, is introduced and implemented in a multiphysics software package. Numerical finite‐element method simulations were used to establish a highly accurate vibroacoustic model in head gradient coils in detail, including the newly introduced Lorentz damping effect. Vibroacoustic coupling was examined through an additional modal analysis. Thorough experimental studies were used to validate simulations.ResultsAverage experimental sound pressure levels (SPLs) and accelerations over the 0‐3000 Hz frequency range were 97.6 dB, 98.7 dB, and 95.4 dB, as well as 20.6 g, 8.7 g, and 15.6 g for the X‐, Y‐, and Z‐gradients, respectively. A reasonable agreement between simulations and measurements was achieved. Vibroacoustic coupling showed a coupled resonance at 2300 Hz for the Z‐gradient that is responsible for a sharp peak and the highest SPL value in the acoustic spectrum.ConclusionWe have developed and used more realistic multiphysics simulation methods to gain novel insights into the underlying concepts for vibroacoustics in head gradient coils, which will permit improved analyses of existing gradient coils and novel SPL reduction strategies for future gradient coil designs. Magn Reson Med 78:1635–1645, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Ordering patterns following the implementation of a healthier children's restaurant menu: A latent class analysis
Authors: Mueller Megan P. , Anzman‐Frasca Stephanie , Blakeley Caitlin E. , Folta Sara C. , Wilde Parke , Economos Christina D. 
Published: November 2016

ObjectiveIdentify ordering patterns following implementation of a healthier children's menu.MethodsA healthier children's menu was introduced in 2012 at a regional restaurant chain, featuring more meals meeting Kids LiveWell (KLW) nutrition standards, KLW side dishes bundled with meals, and the removal of French fries and soda. Latent class analysis was conducted on child meal orders placed after menu implementation (n = 8,611). The average calorie content and proportion of orders meeting calorie recommendations (≤600 kcal) in each class were evaluated.ResultsThe best‐fitting model contained six latent classes representing different ordering patterns: “healthy meals” (27.0%), “healthy meals, add‐ons” (9.6%), “unhealthy sides” (9.2%), “healthy substitutions” (30.9%), “healthy substitutions, add‐ons” (1.0%), and “unhealthy substitutions” (22.4%). Classes denoted as “healthy” were likely to contain meals with KLW items. Orders in the healthy meals class contained fewer calories than orders in all other classes (P < 0.0001). The majority of orders meeting calorie recommendations were in the healthy meals (59.4%) and healthy substitutions (27.1%) classes.ConclusionsOrdering patterns consistent with the healthier menu were common and more likely to meet calorie recommendations. Ordering patterns inconsistent with menu changes also emerged and can inform intervention efforts to reach patrons who may reject or compensate for healthier items.
Oligomerization domains in the glycan‐binding receptors DC‐SIGN and DC‐SIGNR: Sequence variation and stability differences
Authors: dos Santos Ália , Hadjivasiliou Andreas , Ossa Felipe , Lim Novandy K. , Turgut Aylin , Taylor Maureen E. , Drickamer Kurt 
Published: November 2016

AbstractHuman dendritic cell‐specific intercellular adhesion molecule‐1 grabbing nonintegrin, DC‐SIGN, and the sinusoidal endothelial cell receptor DC‐SIGNR or L‐SIGN, are closely related sugar‐binding receptors. DC‐SIGN acts both as a pathogen‐binding endocytic receptor and as a cell adhesion molecule, while DC‐SIGNR has only the pathogen‐binding function. In addition to differences in the sugar‐binding properties of the carbohydrate‐recognition domains in the two receptors, there are sequence differences in the adjacent neck domains, which are coiled‐coil tetramerization domains comprised largely of 23‐amino acid repeat units. A series of model polypeptides consisting of uniform repeat units have been characterized by gel filtration, differential scanning calorimetry and circular dichroism. The results demonstrate that two features characterize repeat units which form more stable tetramers: a leucine reside in the first position of the heptad pattern of hydrophobic residues that pack on the inside of the coiled coil and an arginine residue on the surface of the coiled coil that forms a salt bridge with a glutamic acid residue in the same polypeptide chain. In DC‐SIGNR from all primates, very stable repeat units predominate, so the carbohydrate‐recognition domains must be held relatively closely together. In contrast, stable repeat units are found only near the membrane in DC‐SIGN. The presence of residues that disrupt tetramer formation in repeat units near the carbohydrate‐recognition domains of DC‐SIGN would allow these domains to splay further apart. Thus, the neck domains of DC‐SIGN and DC‐SIGNR can contribute to the different functions of these receptors by presenting the sugar‐binding sites in different contexts.
In Silico Quantum Chemical and Crystallographic Treatment of α‐Formylketene Dithioacetal towards the Elucidation of Its Structural and Optical Nature
Authors: Joy Monu , Alex Neethu , Malayan Jalaja J , Sudarsanakumar C. , Mathews Annie 
Published: November 2016

Abstractα‐Formylketene dithioacetal is a vital precursor for the synthesis of a number of heterocyclic compounds including isoxazoles, pyrimidines, naphthyridines, pyridones, nicotinonitriles and its functionalized materials. Apart from the synthetic applications, the crystalline and non linear optical nature is also considerable, hence the present study deals with the structural and hyperpolarizability aspects of a representative compound from the family of α‐formylketene dithioacetal, 2‐(4‐methoxybenzoyl)‐3,3‐bis(methylsulfanyl)prop‐2‐enal (FKDTA), was synthesized with a reported protocol and characterized. The complete three dimensional solid state structural studies were carried out utilizing single crystal X‐ray crystallographic technique along with Hirshfeld surfaces followed by various quantum chemical parameters were performed including non‐linear optical effects and it is discussed to reveals the complete structural peculiarities towards the optical behaviours of the designated compound.
DFT Analyses of Reaction Pathways and Temperature Effects on various Guaiacol Conversion Reactions in Gas Phase Environment
Authors: Verma Anand Mohan , Kishore Nanda 
Published: November 2016

AbstractGuaiacol component represents the phenolic fraction of bio‐oil. In this numerical study, six reaction pathways originating from guaiacol and yielding anisole, phenol, cyclopentanone and cyclohexanone as the major end products with various intermediates, are carried out. The transition state optimizations, normal mode vibrational frequencies, and intrinsic reaction coordinate calculations are performed under the density functional theory (DFT) framework at B3LYP/6‐311+g(d,p) level of theory. The thermochemistry calculations are carried out at 1 atm pressure and at a wide range of temperature between 298–898 K with an interval temperature of 100 K. Results indicate that all six reactions are both exothermic and spontaneous at each temperature point, however, pathways 1, 2, and 3 show increase in exothermicity and spontaneity with increase in temperature but pathways 4, 5, and 6 show the increase in exothermicity only with increase in temperature while decrement in reaction free energies with increasing temperature.
Efficient Approaches for the Synthesis of Substituted Thiazolo[3,2‐a]‐benzimidazole‐Phosphonates and ‐Phosphinic Diamide Derivatives
Authors: Abdou Wafaa M. , Shaddy Abeer A. , Khidre Maha D. 
Published: November 2016

AbstractPhosphrylation of E‐3‐(dimethylamino)‐1‐(3‐methylbenzo[d]‐thiazolo[3,2‐a]imidazol‐2‐yl)‐prop‐2‐en‐1‐one (1) and 1‐(3‐methylbenzo[d]thiazolo[3,2‐a]imidazol‐2‐yl)ethanone (12) was studied in detail. The enaminone (1) reacted with trialkyl phosphites, dialkylphosphonates, and tris(dialkylamino)‐phosphines to afford the corresponding (E/Z) thiazolobenzimidazol‐3‐oxoprop‐1‐enyl‐phosphonate and phosphonic diamides. The reactions proceeded via phospha‐Michael (P‐Michael) addition reaction, followed by extrusion of HNMe2 moiety and intramolecular migration of the phosphono‐alkyl group. Only the major E‐isomer of the respective oxopropenyl phosphonates was isolated by fractional crystallization (∼ 65% yield) in a pure form whereas the two isomers were chromatography separated and identified in the second case of the respective phosphonic diamide mixtures. The trans‐configuration is also confirmed by nuclear Overhauser effect (NOE) experiments. On the other hand, substituted thiazolobenzimidazole‐α‐hydroxyphosphonate‐ and α‐hydroxyphosphinic diamide derivatives were produced from the reaction of the 2‐acetyl thiazolo[3,2‐a]benzimidazole (12) with the same P(III) reagents via Abramov 1, 2‐addition reaction.
Morphology Control and Electro catalytic Activity towards Oxygen Reduction of Peptide‐Templated Metal Nanomaterials: A Comparison between Au and Pt
Authors: Wang Qiannan , Tang Zhenghua , Wang Likai , Yang Hongyu , Yan Wei , Chen Shaowei 
Published: November 2016

AbstractPeptide templated noble metal nanomaterials have been considered as an emerging type of nanomaterials, which can find widespread catalytic applications in a variety of organic reactions. However, their electrocatalytic properties remained largely unexplored. Herein, peptide R5 templated Au and Pt nanomaterials were fabricated and employed as catalysts for oxygen reduction reaction (ORR). By tuning the metal‐to‐peptide ratio, different shaped Au and Pt nanomaterials were obtained and observed by TEM measurements. With lower metal‐to‐peptide ratios, spherical nanoparticles were obtained for both Au and Pt, while higher metal‐to‐peptide ratios led to the formation of nanoribbons and/or networked nanochains. All the Au and Pt nanomaterials demonstrated good ORR activity, while R5‐Au‐90 and R5‐Pt‐90 exhibited the best performance in their own series. Morphological effects of Au and Pt nanomaterials upon ORR were established. R5‐Pt‐90 exhibited comparable activity with Pt/C, as manifested by the onset potential, specific activity as well as the long‐term durability. The findings can shed light on rational design of peptide templated noble metal nanomaterials with desired morphology and optimized electrochemical properties as catalyst for electrochemical reactions.
Aromaticity in Pericyclic Transition State Structures? A Critical Rationalisation Based on the Topological Analysis of Electron Density
Authors: Domingo Luis R. , Ríos‐Gutiérrez Mar , Chamorro Eduardo , Pérez Patricia 
Published: November 2016

AbstractThe nature of the electron delocalisation pattern within a cyclic structure, i. e. the aromatic character, is examined for six‐memberedpseudocyclictransition state structures (TSs) involved in five representative examples of so‐calledpericyclicreactions. Results of the electron localisation function (ELF) and the quantum theory of atoms in molecules (QTAIM) analyses of the electron density evidence that in four of the cases, at least one pair of atoms are not bound at the TS configuration, thus precluding a possible cyclic conjugation. These findings make it possible to rule out the aromatic character of these TSs. High values of the synchronicity Sy index at the TSs contrast with the bonding changes evidenced by ELF topological analysis. The magnitude of the nucleus independent chemical shift (NICS) computed for the five TSs becomes much more negative than that of the reference system, benzene, with no obvious relation to the strong evidence of the pattern of delocalisation revealed by the topological analysis of ELF and QTAIM for each TS. The topology of the anisotropy of current induced density (ACID) at each TS reveals the actual existence of strong non‐symmetrical patterns of electron delocalisation of the five TSs.
Facile Synthesis of Crystalline Nanoporous GaN Templated by Nitrogen Enriched Mesoporous Carbon Nitride for Friedel‐Crafts Reaction
Authors: Talapaneni Siddulu Naidu , Park Dae‐Hwan , Choy Jin‐Ho , Ramadass Kavitha , Elzatahry Ahmed , Al Balawi Ahmed S. , Al‐Enizi Abdullah M. , Mori Toshiyuki , Vinu Ajayan 
Published: November 2016

AbstractHighly crystalline nanoporous GaN (NP‐GaN) materials have been synthesized for the first time by the transformation of novel diamino tetrazine based mesoporous carbon nitride (MCN‐4) having very high nitrogen content (N/C ratio of 1.8) and GaCl3 through the unique reactive hard templating approach. Powder XRD and HRTEM analysis show that the prepared NP‐GaN is highly pure and possesses excellent crystallinity. N2 adsorption analysis confirm that the samples exhibit mesoporosity with excellent textural parameters including high specific surface areas. It is also demonstrated that NP‐GaN materials show excellent catalytic activity in the Friedel‐Crafts hexanoylation of benzene by using hexanoyl chloride (HC) with excellent conversion of HC. The activity of the NP‐GaN is also compared with MCN‐4, bulk Ga2O3 and GaN. Among the materials studied, NP‐GaN shows the highest catalytic performance in the above mentioned reaction with excellent conversion of HC and product selectivity to hexanophenone.
Preparation of Azine Complexes of Ruthenium(II)
Authors: Albertin Gabriele , Antoniutti Stefano , Castro Jesús , Sibilla Francesca 
Published: November 2016

AbstractAldazine complexes [RuCl(η6‐p‐cymene){κ1‐[N=C(H)R1]‐N=C(H)R1}L]BPh4 (1‐4) [L=P(OMe)3, P(OEt)3, PPh(OEt)2, PiPr3; R1=Ph, 4‐CH3C6H4, 4‐CH3OC6H4, Et] were prepared by allowing chloro compounds RuCl2(η6‐p‐cymene)L to react with the azine R1(H)C=N‐N=C(H)R1 in ethanol. Depending on the nature of the phosphine ligand, the reaction of ketazine (CH3)2C=N‐N=C(CH3)2 with chloro compounds RuCl2(η6‐p‐cymene)L yielded either hydrazone derivatives [RuCl(η6‐p‐cymene){NH2N=C(CH3)2}L]BPh4 (5,6) [L=P(OMe)3, P(OEt)3] or κ1‐azine complex [RuCl(η6‐p‐cymene){κ1‐[N=C(CH3)2]N=C(CH3)2}(PiPr3)]BPh4 (7). Cyclopentadienyl derivatives [Ru(η5‐C5H5){κ1‐[N=C(H)R1]‐N=C(H)R1}(PPh3){P(OMe)3}]+ (10) [R1=Ph, 4‐CH3C6H4, C2H5] were prepared by reacting the chloro compound RuCl(η5‐C5H5)(PPh3)[P(OMe)3] first with AgOTf and then with an excess of azine. Instead, treatment of RuCl(η5‐C5H5)(PPh3)[P(OMe)3] first with AgOTf and then with ketazine (CH3)2C=N‐N=C(CH3)2 in ethanol, yielded hydrazone derivative [Ru(η5‐C5H5){NH2N=C(CH3)2}(PPh3){P(OMe)3}]BPh4 (11). Oxidation of hydrazone derivative 11 with HgO gave dimethyldiazoalkane complex [Ru(η5‐C5H5){N2C(CH3)2}(PPh3){P(OMe)3}]BPh4 (13). The complexes were characterised by spectroscopy and X‐ray crystal structure determination of [RuCl(η6‐p‐cymene){κ1‐[N=C(H)Ph]‐N=C(H)Ph}{P(OMe)3}]BPh4 (1 a), [RuCl(η6‐p‐cymene){κ1‐[N=C(H)Ph]‐N=C(H)Ph}{P(OEt)3}]BPh4 (2 a) and [Ru(η5‐C5H5){NH2N=C(CH3)2}(PPh3){P(OMe)3}]BPh4 (11).
Pushing and pulling Sara: A case study of the contrasting influences of high school and university experiences on engineering agency, identity, and participation
Authors: Godwin Allison , Potvin Geoff 
Published: November 2016

AbstractThis manuscript reports a longitudinal case study of how one woman, Sara, who had previously considered dropping out of high school, authored strong mathematics and science identities and purposefully exhibited agency through her experiences in high school science. These experiences empowered her to choose an engineering major in college; however, her introductory university engineering experiences ultimately pushed her out of engineering. Drawing on critical agency theory, we argue that by paying careful attention to how and why women author their identities and build agency through their experiences in high school, we may gain insight into why women may choose an engineering path in college. Additionally, we examine how Sara's perceptions of engineering structures and practices chipped away at the critical engineering agency she developed and caused her to leave engineering after her first year in college. © 2016 Wiley Periodicals, Inc. J Res Sci Teach 54: 439–462, 2017
A novel constellation amplitude modification method for PAPR reduction in OFDM systems
Authors: Ni Chunxing , Ma Yahui , Jiang Tao 
Published: November 2016

AbstractIn this paper, we propose a constellation amplitude modification (CAM) method to reduce the peak‐to‐average power ratio (PAPR) in orthogonal frequency division multiplexing systems. The key idea of the proposed CAM method is to modify the original constellation amplitude and choose the constellation points with the minimum PAPR as the transmitted constellation points. The CAM method formulates the PAPR reduction as a convex optimization problem, and then, it applies the customized interior‐point method to solve the optimization problem. Compared with the traditional methods, the CAM method does not increase the transmit power, and the receiver has no additional operations. Simulation results show that the CAM method converges fast and offers significant PAPR reduction. Copyright © 2016 John Wiley & Sons, Ltd.
Association patterns and population dynamics of bottlenose dolphins in the Strait of Sicily (Central Mediterranean Sea): implication for management
Authors: Papale Elena , Ceraulo Maria , Giardino Gisela , Buffa Gaspare , Filiciotto Francesco , Grammauta Rosario , Maccarrone Vincenzo , Mazzola Salvatore , Buscaino Giuseppa 
Published: November 2016

AbstractAn understanding of the population dynamics and social organization of cetaceans is essential to manage the influence of anthropogenic activities. In this study, the population size, site fidelity and social interactions of bottlenose dolphins in the Strait of Sicily (Italy) were investigated to provide recommendations for their conservation. Mark‐recapture analysis was based on the encounter histories of 103 marked dolphins from 2004 to 2015. The POPAN formulation of the Jolly–Seber model in MARK software was used to estimate the size of the super‐population. Site fidelity and social organization were estimated for individuals re‐sighted ≥3 times. The estimated population size was 140 (SE = 15.75; 95% CI = 106–164). Dolphins had low site fidelity, and both adults and sub‐adults move outside the study area. Females with calves used the area longer than other individuals. Based on our results, dolphins’ home range likely extended beyond the study area. The mean value of the Half‐Weight Association Index was low and the preferred association was by casual acquaintance. However, we found a distinct aggregation of post‐parturition females during the final 2 years of the study. Therefore, the pattern of association was apparently a response to an ecological requirement, which was the possibility to breed in high productivity waters. Whether these individuals are part of a larger pelagic population is unknown; however, we can conclude that the management of only coastal waters is insufficient for the conservation of dolphins in the Strait of Sicily.
Antenatal manifestations of inborn errors of metabolism: prenatal imaging findings
Authors: Guibaud Laurent , Collardeau‐Frachon Sophie , Lacalm Audrey , Massoud Mona , Rossi Massimiliano , Cordier Marie Pierre , Vianey‐Saban Christine 
Published: November 2016

AbstractPrenatal manifestations of inborn errors of metabolism (IEM) are related to severe disorders involving metabolic pathways active in the fetal period and not compensated by maternal or placental metabolism. Some prenatal imaging findings can be suggestive of such conditions—especially in cases of consanguinity and/or recurrence of symptoms—after exclusion of the most frequent nonmetabolic etiologies. Most of these prenatal imaging findings are nonspecific. They include mainly ascites and hydrops fetalis, intrauterine growth restriction (IUGR), central nervous system (CNS) anomalies, echogenic kidneys, epiphyseal stippling, craniosynostosis, and a wide spectrum of dysostoses. These anomalies can be isolated, but in most cases, an IEM is suggested by an association of features. It must be stressed that the diagnosis of an IEM in the prenatal period is based on a close collaboration between specialists in fetal imaging, medicine, genetics, biology, and pathology.
Sexy online self‐presentation on social network sites and the willingness to engage in sexting: A comparison of gender and age
Authors: van Oosten Johanna M.F. , Vandenbosch Laura 
Published: November 2016

ABSTRACTThe present study investigated whether engaging in sexy self‐presentations on social network sites (SNSs) or exposure to sexy self‐presentations on SNSs predicts the willingness to engage in sexting. A second aim of the present study was to investigate whether adolescent girls demonstrate stronger relationships between (exposure to) sexy online self‐presentations on SNSs and willingness to sext than adolescent boys and young adult men and women. A two‐wave panel survey among 953 Dutch adolescents (13–17 years old, 50.7% male) and 899 Dutch young adults (18–25 years old, 43.9% male) showed that engaging in sexy self‐presentations on SNSs increased the willingness to engage in sexting, but only among adolescent girls. Exposure to sexy self‐presentations of others did not predict the willingness to engage in sexting. The findings call for more research on the role of gender and age in the link between sexy self‐presentation and sexting.