bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isotactic Polypropylene/Multi‐Walled Carbon Nanotube Nanocomposites: The Effect of Modification of MWCNTs on Mechanical Properties and Melt Crystallization
Authors: Papageorgiou George Z. , Nerantzaki Maria , Grigoriadou Ifigeneia , Papageorgiou Dimitrios G. , Chrissafis Konstantinos , Bikiaris Dimitrios 
Published: October 2013

Nanocomposites of isotactic polypropylene (iPP) containing modified multi‐walled carbon nanotubes (MWCNTs) are prepared by melt mixing. MWCNTs with alkyl groups (alkyl‐MWCNTs) and with methyl‐PEG (mPEG‐MWCNTs) are used, as well as unmodified MWCNTs, to prepare the three series of nanocomposites. The surface treatment and the content of MWCNTs affect the mechanical properties of the iPP. In all cases, theoretical models are used to estimate the effect of surface treatment. The crystallization rates of nanocomposites in both isothermal and non‐isothermal crystallization conditions are measured. The nanocomposites containing unmodified MWCNTs crystallize faster than those with modified MWCNTs.
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Hydrophilic–Hydrophobic‐Transition‐Triggered Thermosensitive Macroscopic Gel Assembly
Authors: Peng Yan , Wang Zong‐Chun , Xu Xiao‐Ding , Song Jin‐Chun 
Published: October 2013

Two kinds of poly(N‐isopropylacrylamide) (PNIPAAm)‐based hydrogels containing β‐cyclodextrin (β‐CD) (host gel) and benzyl (guest gel) groups, respectively, are designed and prepared. When mixing the host and guest gels together, due to the presence of the host–guest interaction between the β‐CD and benzyl groups, a combined hydrogel can be formed at a temperature below the lower critical solution temperature (LCST) via macroscopic self‐assembly. When heating this self‐assembling system to a temperature above the LCST, the aggregation of the hydrophobic PNIPAAm‐based chains pull the β‐CD and benzyl groups to separate them from each other, leading to the disassociation of the combined hydrogel. Because of the transition from hydrophobic aggregated PNIPAAm‐based chains to hydrophilic extended ones as the temperature decreases to a value below LCST, the combined hydrogel can re‐form via macroscopic self‐assembly between the host and guest gels. The concept of hydrophilic–hydrophobic transition‐triggered thermosensitive macroscopic self‐assembly can be extended to develop many other stimuli‐responsive materials.
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A Novel Branched Polyoxymethylene Synthesized by Cationic Copolymerization of 1,3,5‐Trioxane with 3‐(Alkoxymethyl)‐3‐ethyloxetane
Authors: Mu Youbing , Jia Mingchen , Jiang Wei , Wan Xiaobo 
Published: October 2013

Novel branched polyoxymethylene copolymers are synthesized by cationic copolymerization of 1,3,5‐trioxane (TOX) with 3‐(alkoxymethyl)‐3‐ethyloxetane (ROX) using BF3·Et2O as an initiator. Four oxetane derivatives with different side‐chain lengths (from 1 to 6 carbons) are tested for copolymerization. The copolymer composition is controlled by the feed ratio of ROX, and influenced by the chain length of alkyl group on ROX. The incorporation ratio and side‐chain length of the ROX unit have great influence on the thermomechanical properties and crystallinity of the copolymers.
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Clinical diagnosis of propriospinal myoclonus is unreliable: An electrophysiologic study
Authors: Erro Roberto , Bhatia Kailash P. , Edwards Mark J. , Farmer Simon F. , Cordivari Carla 
Published: October 2013

ABSTRACTPropriospinal myoclonus is a rare movement disorder that is hypothesized to arise from a spinal generator that transmits activity up and down the spinal cord via long propriospinal pathways. Polymyography is mandatory for the diagnosis, but the typical electrophysiological pattern described for propriospinal myoclonus has been also found in patients with psychogenic axial jerks, supported by the presence of a Bereitschaftspotential (BP; from German, “readiness potential,” also called the premotor potential). We evaluated polymyographic findings in 65 patients referred to us with a clinical diagnosis of propriospinal myoclonus and also looked for the presence of the BP, as detected by jerk‐locked back‐averaging. At clinical reassessment by a movement disorder specialist, nearly one‐half of the patients had clinical clues suggestive of a psychogenic cause of the jerks. Electrophysiological studies were carried out on all 65 patients. Polymyography findings revealed an incongruent electromyographic pattern for propriospinal myoclonus in 84.6% of patients and the presence of the BP in 86.1% of the entire cohort. When taking into account either the presence of BP and/or incongruence of polymyographic features, all patients, including the approximately 50% clinically diagnosed as organic propriospinal myoclonus by a movement disorder expert, had strong neurophysiological evidence for a psychogenic origin of their jerks. The clinical distinction of propriospinal myoclonus from psychogenic axial jerks is unreliable. This is the largest cohort of patients with axial jerks reported so far and we suggest that most of the patients with a clinical picture that clinically resembles propriospinal myoclonus are likely to be psychogenic. © 2013 International Parkinson and Movement Disorder Society
Persistent figure‐eight and side‐to‐side head shaking is a marker for rhombencephalosynapsis
Authors: Tully Hannah M. , Dempsey Jennifer C. , Ishak Gisele E. , Adam Margaret P. , Mink Jonathan W. , Dobyns William B. , Gospe Sidney M. , Weiss Avery , Phillips James O. , Doherty Dan 
Published: October 2013

ABSTRACTBackgroundHead‐shaking stereotypies have been described in patients with neurological impairment. We noted an unusual preponderance of head shaking in patients with rhombencephalosynapsis (RES). We sought to delineate the movements further and determine whether oculomotor and vestibular testing could reveal their cause.MethodsInformation was collected from direct observation, video review and parental questionnaire from 59 patients with RES. Oculomotor and vestibular testing was performed in 4 children.ResultsOf 59 patients, 50 had persistent head shaking that was often observed years before RES was recognized. Three affected children demonstrated abnormal central vestibular processing.ConclusionsHead‐shaking is common in RES. These characteristic movements may provide input to a defective vestibular system or may represent a motor pattern that is usually suppressed by vestibular feedback. Persistent head shaking should alert clinicians to the possible presence of a congenital hindbrain abnormality that affects the vestibulocerebellum, particularly RES. © 2013 International Parkinson and Movement Disorder Society
Impacts of reconnaissance flight data on numerical simulation of tropical cyclones over South China Sea
Authors: Wong Wai Kin , Tse Shuk Mei , Chan Pak Wai 
Published: October 2013

AbstractIn 2011, the Hong Kong Observatory (HKO) and the Government Flying Service (GFS) of the Hong Kong Government conducted reconnaissance data collection flights for two tropical cyclones over the South China Sea. It was the first time in the region that flight measurements of this kind had been carried out specifically for tropical cyclones. Horizontal wind velocity components, temperature and relative humidity at selected flight levels were recorded at the temporal resolution of 20 times per second to delineate the wind flow and other meteorological conditions. They were found to be consistent with other synoptic station data sparsely located over the sea areas, as well as in good agreement with the ocean surface wind data from the satellite microwave scatterometer. In this study, aircraft measurements for the two tropical cyclones in 2011 and one in July 2009 were assimilated into the HKO mesoscale Non‐Hydrostatic Model (NHM) using its three‐dimensional variational data assimilation (3DVAR) to investigate the impact of the data on the model analysis and forecast. Model sensitivity experiments with and without the flight measurements were conducted. The flight observations were found to improve model analysis and forecasts of wind circulation, temperature and humidity in the vicinity of the tropical cyclones. Improvement in track forecast was obtained although an insignificant effect was seen in predicting the central pressure of the storms. The inclusion of flight measurements also improved the forecast of the surface wind distribution and precipitation associated with the tropical cyclones.
A 3 T sodium and proton composite array breast coil
Authors: Kaggie Joshua D. , Hadley J. Rock , Badal James , Campbell John R. , Park Daniel J. , Parker Dennis L. , Morrell Glen , Newbould Rexford D. , Wood Ali F. , Bangerter Neal K. 
Published: October 2013

PurposeThe objective of this study was to determine whether a sodium phased array would improve sodium breast MRI at 3 T. The secondary objective was to create acceptable proton images with the sodium phased array in place.MethodsA novel composite array for combined proton/sodium 3 T breast MRI is compared with a coil with a single proton and sodium channel. The composite array consists of a 7‐channel sodium receive array, a larger sodium transmit coil, and a 4‐channel proton transceive array. The new composite array design utilizes smaller sodium receive loops than typically used in sodium imaging, uses novel decoupling methods between the receive loops and transmit loops, and uses a novel multichannel proton transceive coil. The proton transceive coil reduces coupling between proton and sodium elements by intersecting the constituent loops to reduce their mutual inductance. The coil used for comparison consists of a concentric sodium and proton loop with passive decoupling traps.ResultsThe composite array coil demonstrates a 2–5× improvement in signal‐to‐noise ratio for sodium imaging and similar signal‐to‐noise ratio for proton imaging when compared with a simple single‐loop dual resonant design.ConclusionThe improved signal‐to‐noise ratio of the composite array gives breast sodium images of unprecedented quality in reasonable scan times. Magn Reson Med 71:2231–2242, 2014. © 2013 Wiley Periodicals, Inc.
Field camera measurements of gradient and shim impulse responses using frequency sweeps
Authors: Vannesjo S. Johanna , Dietrich Benjamin E. , Pavan Matteo , Brunner David O. , Wilm Bertram J. , Barmet Christoph , Pruessmann Klaas P. 
Published: October 2013

PurposeApplications of dynamic shimming require high field fidelity, and characterizing the shim field dynamics is therefore necessary. Modeling the system as linear and time‐invariant, the purpose of this work was to measure the impulse response function with optimal sensitivity.Theory and MethodsFrequency‐swept pulses as inputs are analyzed theoretically, showing that the sweep speed is a key factor for the measurement sensitivity. By adjusting the sweep speed it is possible to achieve any prescribed noise profile in the measured system response. Impulse response functions were obtained for the third‐order shim system of a 7 Tesla whole‐body MR scanner. Measurements of the shim fields were done with a dynamic field camera, yielding also cross‐term responses.ResultsThe measured shim impulse response functions revealed system characteristics such as response bandwidth, eddy currents and specific resonances, possibly of mechanical origin. Field predictions based on the shim characterization were shown to agree well with directly measured fields, also in the cross‐terms.ConclusionFrequency sweeps provide a flexible tool for shim or gradient system characterization. This may prove useful for applications involving dynamic shimming by yielding accurate estimates of the shim fields and a basis for setting shim pre‐emphasis. Magn Reson Med 72:570–583, 2014. © 2013 Wiley Periodicals, Inc.
Application of the compressed sensing technique to self‐gated cardiac cine sequences in small animals
Authors: Montesinos Paula , Abascal Juan Felipe P.J. , Cussó Lorena , Vaquero Juan José , Desco Manuel 
Published: October 2013

PurposeSelf‐gated cine sequences are a common choice for cardiac MRI in preclinical applications. The aims of our work were to apply the compressed sensing technique to IntraGateFLASH cardiac MRI studies on rats and to find the maximum acceleration factor achievable with this technique.Theory and MethodsOur reconstruction method extended the Split Bregman formulation to minimize the total variation in both space and time. In addition, we analyzed the influence of the undersampling pattern on the acceleration factor achievable.ResultsOur results show that acceleration factors of up to 15 are achievable with our technique when appropriate undersampling patterns are used. The introduction of a time‐varying random sampling clearly improved the efficiency of the undersampling schemes. In terms of computational efficiency, the proposed reconstruction method has been shown to be competitive as compared with the fastest methods found in the literature.ConclusionWe successfully applied our compressed sensing technique to self‐gated cardiac cine acquisition in small animals, obtaining an acceleration factor of up to 15 with almost unnoticeable image degradation. Magn Reson Med 72:369–380, 2014. © 2013 Wiley Periodicals, Inc.
Evaluation of methoxy polyethylene glycol‐polylactide diblock copolymers as additive in hypromellose film coating
Authors: Cespi Marco , Casettari Luca , Bonacucina Giulia , Giorgioni Gianfabio , Perinelli Diego R , Palmieri Giovanni Filippo 
Published: October 2013

This paper deals with a new application of diblock methoxy polyethylene glycol‐polylactide block copolymers, a class of synthetic biomaterials largely studied in the pharmaceutical and biomedical fields owing to their favorable properties such as biocompatibility, biodegradability, low immunogenicity, and good mechanical properties.In this work, these materials were evaluated as additives for gastro‐soluble pharmaceutical coating aimed to reduce film stiffness and water permeability. Two copolymers with different polylactide chain lengths were synthesized and characterized in term of molecular weight and solid‐state properties. A series of free films with different hypromellose/copolymers ratio were prepared and characterized in terms of appearance, components miscibility, plasticity, and water vapor permeability.The obtained results demonstrate that copolymers effectively influence hypromellose film properties according to their concentration and molecular weight. Specifically, the addition of the copolymer with a molecular weight of 6.5 kDa in a ratio hypromellose:polymer 5:1, allowed to obtain films with good appearance, improved plasticization, and water permeability properties. For higher molecular weight, copolymer or different ratios was not possible to observe the improvement of all the properties at the same time. The results also make possible to define the critical features to improve in order to use block copolymers as additive in hypromellose film coating.The availability of new water‐soluble additives able to work as plasticizer and moisture sealer in polymeric films represents an important progress not only in the field of pharmaceutical coating but also in that of food coatings, as for example in the formulation of edible films. Copyright © 2013 John Wiley & Sons, Ltd.
KRAS (but not BRAF) mutations in ovarian serous borderline tumour are associated with recurrent low‐grade serous carcinoma
Authors: Tsang Yvonne T , Deavers Michael T , Sun Charlotte C , Kwan Suet‐Yan , Kuo Eric , Malpica Anais , Mok Samuel C , Gershenson David M , Wong Kwong‐Kwok 
Published: October 2013

AbstractBRAF and KRAS mutations in ovarian serous borderline tumours (OSBTs) and ovarian low‐grade serous carcinomas (LGSCs) have been previously described. However, whether those OSBTs would progress to LGSCs or whether those LGSCs were developed from OSBT precursors in previous studies is unknown. Therefore, we assessed KRAS and BRAF mutations in tumour samples from 23 recurrent LGSC patients with a known initial diagnosis of OSBT. Paraffin blocks from both OSBT and LGSC samples were available for five patients, and either OSBTs or LGSCs were available for another 18 patients. Tumour cells from paraffin‐embedded tissues were dissected out for mutation analysis by conventional polymerase chain reaction (PCR) and Sanger sequencing. Tumours that appeared to have wild‐type KRAS by conventional PCR–Sanger sequencing were further analysed by full COLD (co‐amplification at lower denaturation temperature)‐PCR and deep sequencing. Full COLD‐PCR was able to enrich the amplification of mutated alleles. Deep sequencing was performed with the Ion Torrent personal genome machine (PGM). By conventional PCR–Sanger sequencing, BRAF mutation was detected only in one patient and KRAS mutations were detected in ten patients. Full COLD‐PCR deep sequencing detected low‐abundance KRAS mutations in eight additional patients. Three of the five patients with both OSBT and LGSC samples available had the same KRAS mutations detected in both OSBT and LGSC samples. The remaining two patients had only KRAS mutations detected in their LGSC samples. For patients with either OSBT or LGSC samples available, KRAS mutations were detected in seven OSBT samples and six LGSC samples. Surprisingly, patients with the KRAS G12V mutation have shorter survival times. In summary, KRAS mutations are very common in recurrent LGSC, while BRAF mutations are rare. The findings indicate that recurrent LGSC can arise from proliferation of OSBT tumour cells with or without detectable KRAS mutations. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Defective control of vitamin D receptor‐mediated epithelial STAT1 signalling predisposes to severe respiratory syncytial virus bronchiolitis
Authors: Stoppelenburg Arie Jan , von Hegedus Johannes Hendrick , Huis in't Veld Ron , Bont Louis , Boes Marianne 
Published: October 2013

AbstractRespiratory syncytial virus (RSV) infection causes bronchiolitis in infants with seasonal frequency, for which vitamin D deficiency and a well‐described polymorphism in the vitamin D receptor (VDR) FokI are important risk factors. Recent studies suggest that vitamin D regulates immune pathways in airway epithelial cells during RSV infection. It is not understood why the VDR FokI polymorphism predisposes to severe RSV bronchiolitis. We investigated how the VDR FokI polymorphism regulates the epithelial response to RSV infection. To this end, we over‐expressed the normal and FokI VDR variants in A549 airway epithelial cells. Vitamin D restrained the expression of both NFκB‐ and STAT1‐induced antiviral genes. However, while NFκB control by vitamin D remained intact, both RSV‐induced phosphorylation of STAT1 and expression of its downstream targets, IRF1 and IRF7, escaped vitamin D control in FokI epithelial cells. The poor capacity of vitamin D to regulate IRF1 in FokI VDR‐expressing cells was recapitulated using blood samples from normal and FokI VDR‐genotyped healthy donors. Hence, we provide mechanistic insight that the FokI VDR polymorphism renders STAT1‐mediated antiviral immune reactions to RSV infection non‐responsive to vitamin D control, resulting in enhanced immunopathology and exacerbated RSV bronchiolitis. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
External validity and reliability of the psychosocial assessment tool (PAT) among Canadian parents of children newly diagnosed with cancer
Authors: Barrera M. , Hancock K. , Rokeach A. , Cataudella D. , Atenafu E. , Johnston D. , Punnett A. , Nathan PC. , Bartels U. , Silva M. , Cassidy M. , Jansen P. , Shama W. , Greenberg C. 
Published: October 2013

AbstractBackgroundThe Psychosocial Screening Tool (PAT) was developed and validated with a sample of caregivers of children newly diagnosed with cancer in the United States. This study aimed to assess cultural adaptation (Phase 1) and validity and reliability of the revised PAT (PATrev) with a Canadian sample (Phase 2).ProcedureIn Phase 1, a convenience sample of seven parents of children who were treated for cancer and six pediatric oncology healthcare experts participated. In Phase 2, 67 parents of children newly diagnosed with cancer from 4 Canadian pediatric cancer centers participated. To assess reliability and validity of the PATrev, parents completed behavioral (BASC‐2) and quality of life (PedsQL) instruments about the child and an anxiety inventory (STAI) about themselves.ResultsThe PAT required minor changes to be culturally adapted for the Canadian population. The PATrev had strong inter‐rater (0.77) test–retest (0.75), and internal consistency reliability (0.85), as well as moderate to strong validity comparing PATrev child's problems and PedsQL total (−0.49), PedsQL anxiety (−0.47), BASC‐2 internalizing (0.64), behavioral (0.63), and adaptive scores (−0.56). PATrev discriminative validity was confirmed with BASC‐2 scores (AUR scores of 0.70–0.74). PATrev parental stressors were strongly correlated to STAI scores (0.53). Finally, agreement between PATrev child's problems and parental anxiety scores was moderate (0.47).ConclusionThis study supports the original PAT, demonstrates PATrev is a reliable and valid psychosocial screening tool, and provides unique evidence regarding early psychosocial risk in the family, which have important implications for guiding psychosocial practice. Pediatr Blood Cancer 2014;61:165–170. © 2013 Wiley Periodicals, Inc.
Optical Measurement of Peak Air Shock Pressures Following Explosions
Authors: McNesby Kevin L. , Biss Matthew M. , Benjamin Richard A. , Thompson Ronnie A. 
Published: October 2013

AbstractHigh speed video and streak camera imaging are used to measure peak pressures for explosions of spherical charges of the high explosive C‐4 (92 % trimethylenetrinitramine, C3H6N6O6). The technique measures the velocity of the air shock produced by the detonation of the explosive charges, converts this velocity to a Mach number, and uses the Mach number to determine a peak shock pressure. Peak pressure measurements are reported from a few millimeters to approximately one meter from the charge surface. Optical peak pressure measurements are compared to peak pressures measured using piezoelectric pressure transducers, and to peak pressure measurements estimated using the blast computer code CONWEP. A discussion of accuracy of peak pressures determined optically is provided.