bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and evaluation of a pentafluorobenzamide stationary phase for HPLC separations in the reversed phase and hydrophilic interaction modes
Authors: Ferreira Claudio de Castro , Gama Mariana Roberto , da Silva Gisele Silvestre , Almeida Wanda Pereira , Collins Carol Hollingworth , Jardim Isabel Cristina Sales Fontes 
Published: August 2018

AbstractA pentafluorobenzamide stationary phase was synthesized by an easy method with no intermediate purification steps. Physicochemical characterization (elemental analysis, fourier transform infrared spectroscopy, 29Si and 13C nuclear magnetic resonance spectroscopy) confirmed the presence of pentafluorobenzamide functionalization on the surface of the silica particles. The pentafluorobenzamide stationary phase proved to be quite versatile as it can be used in two different modes in liquid chromatography: reversed phase and hydrophilic interaction liquid chromatography. Chromatographic characterizations in both modes confirmed the multiple interactions established by the new stationary phase, such as hydrogen bonding and π‐π and ion‐exchange interactions. The pentafluorobenzamide stationary phase was successfully employed for the separation of nucleosides and antihypertensive drugs under hydrophilic interaction liquid chromatography conditions, as well as pesticides and benzodiazepine using reversed phase conditions. The stationary phase showed significant potential when compared with commercial columns.
Examining incentive travelers: How motivation affects organizational commitment
Authors: Li Xiaoli , Lu Lu , Chi Christina Geng‐Qing 
Published: August 2018

AbstractThis study examines incentive travelers' motivation and the relationships between motivation, satisfaction, and organizational commitment. A mixed‐methods approach was employed to customize the measures and provide empirical evidence on proposed interrelationships. Factor analysis has revealed three types of travel motivation, including “travel for business networking,” “travel for leisure,” and “travel for prestige.” Partial least squares structural equation modeling results suggest that the three motivations are positively related to satisfaction with incentive travel. Travel for business networking and travel for prestige exhibit positive effects, whereas travel for leisure has a negative effect on organizational commitment. All the three motivations are positively related to organizational commitment through satisfaction.
Zwitterionic Copolymerization of β‐Butyrolactone with Styrene
Authors: Xiao Meina , Jiang Jingxing , Zhang Tongtong , Xu Anli , Ke Zhuofeng , Hong Liangzhi 
Published: August 2018

AbstractThe hybrid copolymerization of vinyl monomers with cyclic esters endows the formed copolymers new features, such as biodegradability and functionality. However, the recently reported hybrid copolymerizations are mainly based on polar vinyl monomers and cyclic esters catalyzed by organocatalysts. The copolymerization of non‐polar vinyl monomers with cyclic esters is still a challenge. In this work, the copolymerization of β‐butyrolactone (β‐BL) with styrene catalyzed by B(C6F5)3 in the absence of coinitiators is reported. The density functional theory studies suggest the formation of zwitterion between β‐BL and B(C6F5)3. It is found that β‐BL and styrene are concurrently copolymerized through the macro‐zwitterion intermediates. The obtained copolymers are carefully examined by 1H NMR, 2D 1H‐13C HMBC, differential scanning calorimetry, thermogravimetric analysis, hydrolysis experiments, as well as Brady's reagents.
Electrochemically Generated Conjugated Microporous Polymer Network Thin Films for Chemical Sensor Applications
Authors: Suresh Venkata M. , Scherf Ullrich 
Published: August 2018

AbstractElectrogenerated π‐conjugated microporous polymer network (CMPN) thin films are potential materials for highly sensitive detection of harmful chemical species as they show fast response, high signal amplification, and easy fabrication of devices. In the last few years, several CMPN thin films from carbazolyl and thienyl monomer building blocks having a variety of aromatic cores have been reported for different applications including organic electronics, electrochemical supercapacitors, chemical sensors. This article reviews the approaches toward the preparation of electrogenerated CMPN thin films and their application in electrochemical and fluorescence quenching–based sensing of nitroaromatics, metal ions, etc.
Controlled ROMP Synthesis of Ferrocene‐Containing Amphiphilic Dendronized Diblock Copolymers as Redox‐Controlled Polymer Carriers
Authors: Liu Xiong , Qiu Guirong , Zhang Li , Liu Fangfei , Mu Shengdong , Long Yanru , Zhao Qiuxia , Liu Yue , Gu Haibin 
Published: August 2018

AbstractNovel well‐defined redox‐responsive Ferrocene (Fc)‐containing amphiphilic dendronized diblock copolymers are synthesized by the ring‐opening metathesis polymerization technique using Grubbs’ third‐generation olefin metathesis catalyst as the initiator. These dendronized block copolymers can self‐assemble into spherical micelles in aqueous solution. The size of self‐assembled micelles can be modulated by the composition (namely, the ratio of hydrophobic and hydrophilic segments) and concentration of the dendronized copolymers. The obtained micelles show reversible redox‐controlled self‐assembly behaviors using FeCl3 as oxidant and glutathione as reductant. Furthermore, the model molecule Rhodamine B is successfully loaded in these micelles, and the oxidation‐triggered controllable release is achieved by changing the type of oxidants (FeCl3 and H2O2) and their concentrations. This is the first example of redox‐responsive micelles self‐assembled by novel amphiphilic dendronized Fc‐containing block copolymers, and the present micelles are visualized to be potential candidates in many fields, especially in stimuli‐responsive drug delivery systems.
A Variable Stiffness Spring–Sponge Composite Tube with Fast Response and Shape Recovery
Authors: Ren Xuyang , Zhang Guokai , Shang Zufeng , Wang Shuxin 
Published: August 2018

AbstractSoft robots have attracted more and more attention from researchers in the past decades, and multiple materials and methods have been studied to solve the conflict between strength and adaptability. This paper presents a novel composite tube comprising a spring and sponge, which can transform between stiffness and softness, and also proposes a corresponding novel method to alter the stiffness of the tube swiftly and reliably. Additionally, studies indicate that the tube exhibits shape‐recovery ability. The potential applications of the tube are illustrated in a coat of the supporting structure in the natural orifice transluminal endoscopic surgery instrument, a fixing device for human arthrosis and skeleton rehabilitation, and a variable stiffness multidirectional actuator.
Direct Femtosecond Laser Printing of PPV on Bacterial Cellulose‐Based Paper for Flexible Organic Devices
Authors: Avila Oriana I. , Santos Moliria V. , Shimizu Flavio M. , Almeida Gustavo F. B. , Siqueir Jonathas P. , Andrade Marcelo B. , Balogh Debora T. , Ribeiro Sidney J. L. , Mendonca Cleber R. 
Published: August 2018

AbstractCellulose‐based flexible electronics has prompted as an interesting approach for the development of novel technologies, given its unique properties. Standard printing methods, however, limit the materials to be transferred, as well as the resolution of the patterns. In this paper the use of femtosecond laser induced forward transfer is demonstrated, for creating high‐resolution patterns of the conductive poly(p‐phenylene vinylene) (PPV), an advanced material that presents outstanding electrical properties, on bacterial cellulose (BC) substrate. Such an approach successfully allows transferring PPV with a resolution on the order of 10 µm and without the material's degradation, which is subsequently doped to increase the electrical conductivity. Therefore, results presented herein open new avenues in the fabrication of paper‐based devices, by combining high resolution and new classes of patterning materials.
Processing‐Driven Morphology Development and Crystallization Behavior of Immiscible Polylactide/Poly(Vinylidene Fluoride) Blends
Authors: Salehiyan Reza , Ray Suprakas Sinha , Ojijo Vincent 
Published: August 2018

AbstractProcessing‐driven morphology development and crystallization behavior of immiscible polymer blends are of high significance for the development of polymeric materials with controllable properties. This study correlates processing‐induced morphology alterations of different polylactide/poly(vinylidene fluoride) (PLA/PVDF) blends with their crystallization behavior, showing that blending can benefit the crystallization of both phases. X‐ray diffraction analysis reveals the facile formation of β‐PVDF crystals upon 10‐min blending of a 30/70 (w/w) PLA/PVDF ratio, which is ascribed to the more uniform distribution of smaller PLA droplets in the PVDF matrix observed for this composition and processing time. On the other hand, dispersion of smaller PVDF droplets inside the PLA matrix increases the crystallinity of the latter, while the crystallinity of PVDF droplets is increased by their coalescence. The results of differential scanning calorimetry (DSC) analysis confirm that PVDF promotes the crystallization of PLA by improving its crystallization enthalpy in blends, whereas no such effect is observed for crystallization of neat PLA from the melt. Finally, nonisothermal DSC analysis of a 50/50 PLA/PVDF blend at different cooling rates reveals that slow crystallization results in enhanced blend crystallinity.
Expected intrinsic volumes and facet numbers of random beta‐polytopes
Authors: Kabluchko Zakhar , Temesvari Daniel , Thäle Christoph 
Published: August 2018

AbstractLet be i.i.d. random points in the d‐dimensional Euclidean space sampled according to one of the following probability densities:
urn:x-wiley:0025584X:media:mana201700255:mana201700255-math-0002and
urn:x-wiley:0025584X:media:mana201700255:mana201700255-math-0003We compute exactly the expected intrinsic volumes and the expected number of facets of the convex hull of . Asymptotic formulae were obtained previously by Affentranger [The convex hull of random points with spherically symmetric distributions, 1991]. By studying the limits of the beta case when , respectively , we can also cover the models in which are uniformly distributed on the unit sphere or normally distributed, respectively. We obtain similar results for the random polytopes defined as the convex hulls of and . One of the main tools used in the proofs is the Blaschke–Petkantschin formula.
Identification of paternal uniparental disomy on chromosome 22 and a de novo deletion on chromosome 18 in individuals with orofacial clefts
Authors: Oseni Ganiyu O. , Jain Deepti , Mossey Peter A. , Busch Tamara D. , Gowans Lord J.J. , Eshete Mekonen A. , Adeyemo Wasiu L. , Laurie Cecelia A. , Laurie Cathy C. , Owais Arwa , Olaitan Peter B. , Aregbesola Babatunde S. , Oginni Fadekemi O. , Bello Saidu A. , Donkor Peter , Audu Rosemary , Onwuamah Chika , Obiri‐Yeboah Solomon , Plange‐Rhule Gyikua , Ogunlewe Olugbenga M. , James Olutayo , Halilu Taiye , Abate Firke , Abdur‐Rahman Lukman O. , Oladugba Abimbola V. , Marazita Mary L. , Murray Jeffrey C. , Adeyemo Adebowale A. , Butali Azeez 
Published: August 2018

AbstractBackgroundOrofacial clefts are the most common malformations of the head and neck region. Genetic and environmental factors have been implicated in the etiology of these traits.MethodsWe recently conducted genotyping of individuals from the African population using the multiethnic genotyping array (MEGA) to identify common genetic variation associated with nonsyndromic orofacial clefts. The data cleaning of this dataset allowed for screening of annotated sex versus genetic sex, confirmation of identify by descent and identification of large chromosomal anomalies.ResultsWe identified the first reported orofacial cleft case associated with paternal uniparental disomy (patUPD) on chromosome 22. We also identified a de novo deletion on chromosome 18. In addition to chromosomal anomalies, we identified cases with molecular karyotypes suggesting Klinefelter syndrome, Turner syndrome and Triple X syndrome.ConclusionObservations from our study support the need for genetic testing when clinically indicated in order to exclude chromosomal anomalies associated with clefting. The identification of these chromosomal anomalies and sex aneuploidies is important in genetic counseling for families that are at risk. Clinicians should share any identified genetic findings and place them in context for the families during routine clinical visits and evaluations.
Microdosimetric considerations for radiation response studies using Raman spectroscopy
Authors: Oliver Patricia A. K. , Thomson Rowan M. 
Published: August 2018

PurposeRecent Raman spectroscopy (RS) studies of radiation response involve subcellular (μm‐scale) sampling volumes and macroscopic doses as low as 0.005 Gy. These studies ignore the stochastic nature of radiation transport and energy deposition, which can lead to considerable microdosimetric “spread” (i.e., variation in energy deposition). The goal of this work is to use Monte Carlo (MC) simulations to investigate the microdosimetric spread across populations of microscopic targets relevant for RS studies of cellular radiation response.MethodsSimulation geometries involve populations of 1600 cells, with two sizes of sampling volumes (representative of recent RS studies) considered within each nucleus, as well as averaging over multiple sampling volumes in the same nucleus. To investigate variation in microdosimetric spread as a function of dose and target size, simple cubic voxel geometries are also considered. MC simulations are used to score energy imparted per unit mass (specific energy, z) in targets (nuclei, sampling volumes, and voxels), considering doses from a few mGy to several Gy. Three photon spectra are considered: 120 kVp x‐ray, cobalt‐60, and a 6 MV medical linac.ResultsFor μm‐sized targets, there can be considerable variation in energy deposition across a population of targets: the specific energy distribution is skewed, a large fraction of targets receive no energy, and the standard deviation of the specific energy relative to the mean, , is considerable. These results vary with source energy and (macroscopic) dose: for 60Co with cylindrical nuclei of 12.8 μm height and diameter, is 17% at 0.02 Gy, decreasing to 2% at 2 Gy. In contrast, for cylindrical sampling volumes with 1 μm diameter and 4 μm height, is 170% at 0.02 Gy and 18% at 2 Gy. Results of MC simulations involving cubic voxel geometries are fit to an equation relating the relative standard deviation of the specific energy to the target volume and dose; additionally, specific energy distributions are compared with normal distributions.ConclusionsMicrodosimetric considerations are important for RS cellular radiation response studies, especially for low doses. The results of this work may motivate changes to current measurement and data analysis methods for RS experiments, and motivate future work comparing MC simulation results with RS measurements to advance understanding of radiation response.
The effect of the flattening filter on photoneutron production at 10 MV in the Varian TrueBeam linear accelerator
Authors: Montgomery Logan , Evans Michael , Liang Liheng , Maglieri Robert , Kildea John 
Published: August 2018

PurposeNeutrons are an unavoidable by‐product of high‐energy radiation therapy treatments that deliver unwanted nontarget dose to patients. Use of flattening‐filter‐free (FFF) photon beams has been shown to significantly reduce photoneutron production per monitor unit (MU) of dose delivered. The purpose of this investigation was to characterize the photoneutron production of the 10 MV and 10 MV FFF beams of the Varian TrueBeamTM linear accelerator.MethodsNeutron fluence spectra were measured using a Nested Neutron SpectrometerTM (NNS, Detec Inc., Gatineau, Canada). The ratios of neutron fluence and ambient dose equivalent for the 10 MV FFF beam relative to the 10 MV beam, dubbed FF‐ratios (FFF/FF), were used to characterize the difference between the two beams. FF‐ratios were compared under the following three conditions (a) per MU, at various locations in the treatment room, (b) per MU, with the linac jaws opened and closed, and (c) per electron striking the bremsstrahlung target, as opposed to per MU, at one location with the jaws closed.ResultsOn average, the neutron fluence for the 10 MV FFF beam was 37% lower per MU than the 10 MV beam (FF‐ratio = 0.63). The FF‐ratio in neutron fluence and ambient dose equivalent did not vary by much between different locations within the treatment room. However, the FF‐ratio in neutron ambient dose equivalent was reduced significantly when the linac jaws were opened compared to closed, which implies that the jaws contribute more to the photoneutron spectrum of the 10 MV FFF beam than to the 10 MV beam. Finally, it was found that the 10 MV FFF beam produces more photoneutrons per electron striking the bremsstrahlung target than the 10 MV beam (FF‐ratio = 2.56).ConclusionsThe photoneutron fluence per MU produced by the 10 MV FFF beam is 37% lower than the 10 MV beam of a Varian TrueBeam linac. Accordingly, a reduction in neutron dose received by patients is achieved through use of the unflattened beam, provided that treatment plans for each beam require approximately the same number of MU. It was found to be instructive to compare the photoneutron yield per source electron between the two beams as it helped provide an understanding of the physics underlying photoneutron production in both beams.
An NMR crystallography investigation of furosemide
Authors: Zilka Miri , Yates Jonathan R. , Brown Steven P. 
Published: August 2018

AbstractThis paper presents an NMR crystallography study of three polymorphs of furosemide. Experimental magic‐angle spinning (MAS) solid‐state NMR spectra are reported for form I of furosemide, and these are assigned using density‐functional theory (DFT)‐based gauge‐including projector augmented wave (GIPAW) calculations. Focusing on the three known polymorphs, we examine the changes to the NMR parameters due to crystal packing effects. We use a recently developed formalism to visualise which regions are responsible for the chemical shielding of particular sites and hence understand the variation in NMR parameters between the three polymorphs.
Differentiation of the phenolic chemical profiles ofCecropia pachystachyaandCecropia hololeuca
Authors: da Silva Mathias Marcelo , Rodrigues de Oliveira Rodrigo 
Published: August 2018

AbstractIntroductionCecropia pachystachyaandC. hololeucaare common species in Brazil, popularly used to treat respiratory diseases. Phytochemical studies indicate that their leaves are rich in phenolic compounds, mainlyC‐glycosilated flavonoids. Orientin and isoorientin are reported in both species, while vitexina and isovitexina were reported inC. pachystachya. In addition, both are rich in chlorogenic acid and have some procyanidins. In some cases, syrups and teas are prepared from leaf blends from different species, which may affect the efficacy and safety of this natural medication. This problem motivated the investigation of the chemical profile of leaves of these species.ObjectiveThe phenolic chemical profiles fromC. pachystachyaandC. hololeucamethanolic extracts were analysed by ultra‐high performance liquid chromatography coupled with a diode array detector and mass spectrometry (UPLC‐DAD‐MS), to investigate possible differences in their metabolite production.Material and MethodsThe methanolic extracts of both species were analysed by UPLC‐DAD‐MS using a C‐18 reverse phase column, DAD at 190–400 nm and electrospray ionisation quadruple time‐of‐flight (ESI‐Q‐TOF) mass spectrometer. The separation methodology was validated and most of the flavones present in the extracts were quantified.ResultsThirty‐seven compounds were tentatively identified, including flavonoids, phenolic acids, flavan‐3‐ols, condensed tannins (procyanidins) and iridoids, through UV analysis and tandem mass spectrometry (MS/MS) spectra obtained in the negative mode. Chlorogenic acid, orientin and isoorientin were observed as the major constituents in both extracts.ConclusionsCecropia pachystachyapresented a more diverse chemical profile thanC. hololeuca. The methodology developed herein could be an important tool to analyse commercialCecropia(embaúba) products.
The several facets of Trichogin GA IV: High affinity Tb(III) binding properties. A spectroscopic and molecular dynamics simulation study
Authors: Gatto Emanuela , Palleschi Maria Elena , Zangrilli Beatrice , De Zotti Marta , Di Napoli Benedetta , Palleschi Antonio , Mazzuca Claudia , Formaggio Fernando , Toniolo Claudio , Venanzi Mariano 
Published: August 2018

AbstractTrichogin GA IV (TrGA) is an antimicrobial peptide isolated from Trichoderma longibrachiatum. The amino acid sequence of TrGA is rather peculiar, because it is characterized by three Aib and four Gly residues, which confer unique dynamic and structural properties. In a previous study, we found that TrGA shows excellent binding properties to Ca(II) and lanthanide Gd(III) ions in acetonitrile solutions. Within the lanthanide ions, Tb(III) ions possess fascinating optical characteristics, such as luminescence which greatly improves after coordination. Here, we present the results of our spectroscopic and molecular dynamics investigations on the Tb(III) ion‐binding properties of an Nα‐Fmoc functionalized analog of Trichogin GA IV (F0TrOMe). The high Tb(III) ion‐F0TrOMe affinity, together with the proteolytic resistance and membrane affinity of the natural compound, confers to this system potentially promising applications in several fields, such as bioimaging and bioanalytical assays.
Molecular simulation of structure formation and rheological properties of mixtures of telechelic and monofunctional associating polymer
Authors: Furuya Tsutomu , Koga Tsuyoshi 
Published: August 2018

ABSTRACTWe study the phase behavior, the characteristic times, and the rheological properties under the steady shear flow of the mixtures consisting of telechelic and monofunctional associating polymers by a coarse‐grained molecular dynamics simulation. The mixtures form the transient networks, the closely packed spherical micelles, and the wormlike micelles. We confirm the molecular origins of the several characteristic times of the mixtures. The dependencies of the characteristic times on the composition ratio between telechelic and monofunctional associating polymers show good agreement with reported experimental results. Under the steady shear flow, the mixtures show the shear thinning induced by the change of the spatial configuration of the micelles. The telechelic associating polymers especially play an important role in connecting the micelles at the shear thinning regime and enhance the steady shear viscosity. Furthermore, at the wormlike micellar region, the mixtures show the second shear thinning initiated by the transformation of the association conformation of the telechelic associating polymers.