bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and optimization of a novel poly‐silicic metal coagulant from coal gangue for tertiary‐treatment of coking wastewater
Authors: Li Jianfeng , Liu Xinyuan , Wang Shujun , Du Zhiping , Guo Yimin , Cheng Fangqin 
Published: July 2017

AbstractBACKGROUNDBio‐treated coking wastewater is difficult to treat further, mainly due to the bio‐refractory organic content. Coal gangue is the largest solid waste in China and it contains large amounts of aluminum, iron and silicon. This study attempts to recover the waste in coal gangue as a novel poly‐silicic metal coagulant for bio‐treated coking wastewater treatment.RESULTSThe poly‐silicic metal coagulant was synthesized from coal gangue under different conditions. Fourier transform infrared spectroscopy, X‐ray diffraction and scanning electron microscopy confirmed that both amorphous and crystalline phases were present in the samples and new chemical bonds such as Si–O–Al and Si–O–Fe were formed. The results show that the composite coagulant was effective for organic removal from the bio‐treated coking wastewater and the optimal Al/Fe/Si molar ratios were Al/Fe = 3 and (Al + Fe)/Si = 13. The removal of organics exhibits a parabolic curve as the coagulant dosage increases. However, the optimal dosage (125 mg L‐1) for organic removal was not equal to the isoelectric point (100 mg L‐1). Furthermore, SEM images showed that the flocs start to disintegrate at a dosage of 150 mg L‐1, leading to deteriorating sludge settling.CONCLUSIONSIt is feasible to fabricate poly‐silicic metal coagulants for coking wastewater treatment by using coal gangue as the raw material. The removal of the bio‐refractory organics by the composite coagulant was attributed to the combined effects of charge neutralization, bridge adsorption and the net capturing. © 2017 Society of Chemical Industry
A new method using Scanning Electron Microscopy (SEM) for preparation of anisopterous odonates
Authors: del Palacio Alejandro , Sarmiento Patricia Laura , Javier Muzón 
Published: July 2017

AbstractAnisopterous odonate male's secondary genitalia is a complex of several structures, among them the vesica spermalis is the most informative with important specific characters. The observation of those characters, mostly of membranous nature, is difficult in the Scanning Electron Microscope due to dehydration and metallization processes. In this contribution, we discuss a new and low cost procedure for the observation of these characters in the SEM, compatible with the most common agents used for preserving specimens.
Completing orientations of partially oriented graphs
Authors: Bang‐Jensen J. , Huang J. , Zhu X. 
Published: July 2017

AbstractWe initiate a general study of what we call orientation completion problems. For a fixed class of oriented graphs, the orientation completion problem asks whether a given partially oriented graph P can be completed to an oriented graph in by orienting the (nonoriented) edges in P. Orientation completion problems commonly generalize several existing problems including recognition of certain classes of graphs and digraphs as well as extending representations of certain geometrically representable graphs.We study orientation completion problems for various classes of oriented graphs, including k‐arc‐strong oriented graphs, k‐strong oriented graphs, quasi‐transitive‐oriented graphs, local tournaments, acyclic local tournaments, locally transitive tournaments, locally transitive local tournaments, in‐tournaments, and oriented graphs that have directed cycle factors. We show that the orientation completion problem for each of these classes is either polynomial time solvable or NP‐complete. We also show that some of the NP‐complete problems become polynomial time solvable when the input‐oriented graphs satisfy certain extra conditions. Our results imply that the representation extension problems for proper interval graphs and for proper circular arc graphs are polynomial time solvable. The latter generalizes a previous result.
Supramolecular interactions between β‐lapachone with cyclodextrins studied using isothermal titration calorimetry and molecular modeling
Authors: Xavier‐Junior Francisco H. , Rabello Marcelo M. , Hernandes Marcelo Z. , Dias Marília E.S. , Andrada Otoni H.M.S. , Bezerra Beatriz P. , Ayala Alejandro P. , Santos‐Magalhães Nereide S. 
Published: July 2017

AbstractSupramolecular interactions between β‐lapachone (β‐lap) and cyclodextrins (CDs) were investigated by isothermal titration calorimetry. The most favorable host: guest interaction was characterized using X‐ray powder diffraction (XRD), differential scanning calorimetry and thermogravimetry (DSC/TG), spectroscopy (FT‐IR), spectroscopy (2D ROESY) nuclear magnetic resonance (NMR), and molecular modeling. Phase solubility diagrams showed β‐, HP‐β‐, SBE‐β‐, γ‐, and HP‐γ‐CDs at 1.5% (w/w) allowed an increase in apparent solubility of β‐lap with enhancement factors of 12.0, 10.1, 11.8, 2.4, and 2.2, respectively. β‐lap has a weak interaction with γ‐ and HP‐γ‐CDs and tends to interact more favorably with β‐CD and its derivatives, especially SBE‐β‐CD (K = 4160 M−1; ΔG = −20.66 kJ·mol−1). Thermodynamic analysis suggests a hydrophobic interaction associated with the displacement of water from the cavity of the CD by the β‐lap. In addition, van der Waals forces and hydrogen bonds were responsible for the formation of complexes. Taken together, the results showed intermolecular interactions between β‐lap and SBE‐β‐CD, thereby confirming the formation of the inclusion complex. Molecular docking results showed 2 main orientations in which the interaction of benzene moiety at the wider rim of the SBE‐β‐CD is the most stable (average docking energy of −7.0 kcal/mol). In conclusion, β‐lap:SBE‐β‐CD is proposed as an approach for use in drug delivery systems in cancer research.
Betamethasone‐based chiral electrochemical sensor coupled to chemometric methods for determination of mandelic acid enantiomers
Authors: Borazjani Marjan , Mehdinia Ali , Jabbari Ali 
Published: July 2017

AbstractA chiral biosensing platform was developed using betamethasone (BMZ) as chiral recognition element through multilayered electrochemical deposition of BMZ, overoxidized polypyrrole, and nanosheets of graphene (OPPy‐BMZ/GR), for enantio‐recognition of mandelic acid (MA) enantiomers. The deposited film was characterized by scanning electron microscopy, differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectroscopy. It was shown that the chiral sensing platform can discriminate R‐ and S‐MA differential pulse voltammetry signals, at the voltages of 1.35 and 1.33 V (vs Ag/AgCl), respectively. To tackle the problem of highly overlapping peaks of these enantiomers, the partial least squares (PLS) regression and genetic algorithm‐PLS (GA‐PLS) were used for simultaneous quantification of MA enantiomers. Generally, variable selection by genetic algorithm provided an improvement in prediction results when compared to full‐voltammogram PLS. Good analytical performances were obtained despite the inherent complexity of the simultaneous determination.
Advanced pharmacy practice in Australia and leadership: mapping the APPF against an evidence‐based leadership framework
Authors: Waddell Jason J. , Nissen Lisa M. , Hale Andrew R. 
Published: July 2017

AbstractBackgroundLeadership skills development is a neglected part of addressing the health workforce crisis facing the world. Models of advanced pharmacy practice include competencies related to leadership and management. Transformational leadership, a contemporary leadership theory, is seen as the most suitable for addressing the challenges facing the modern healthcare system.AimTo map leadership and management competencies of the Australian Advanced Pharmacy Practice Framework 2012 (APPF) against an evidence‐based model of transformational leadership.MethodsDomains of the APPF were mapped against the dimensions of a transformational leadership model developed in the United Kingdom public service.ResultsThere were broad differences between the APPF and a model of transformational leadership. The APPF focuses heavily on ‘organisational’ skills such as strategic vision and setting direction, while the model of transformational leadership focused on the ‘people skills’ of effective leaders. The APPF mapped primarily to the ‘Leading the Organisation’ dimensions of transformational leadership.ConclusionThere are significant differences between the leadership and management competencies of the APPF and the dimensions of transformational leadership. Future work on the competency standards for general and advanced levels of practice should include or refer to an evidence‐based model of transformational leadership.
Fumigation of Brazil nuts with allyl isothiocyanate to inhibit the growth of Aspergillus parasiticus and aflatoxin production
Authors: Lopes Lucas F , Bordin Keliani , de Lara Gabriel HC , Saladino Federica , Quiles Juan M , Meca Giuseppe , Luciano Fernando B 
Published: July 2017

AbstractBACKGROUNDBrazil produces approximately 40 000 tons of Brazil nuts annually, which is commonly contaminated with fungi and mycotoxins. Gaseous allyl isothiocyanate (AITC) was used to inhibit the growth of Aspergillus parasiticus and its production of aflatoxins (AFs) in Brazil nuts.RESULTSNuts were inoculated with 104 spores g−1 of A. parasiticus and placed in airtight glass jars with controlled relative humidity (RH = 95 or 85%). Samples were treated with 0, 0.5, 1.0 or 2.5 µL L−1 of gaseous AITC and analyzed after 30 days to determine the fungal population and AFs content. Samples were also submitted to sensory evaluation. AITC at 2.5 µL L−1 could completely inhibit the fungal growth and AFs production in both the RH tested. AITC at 0.5 and 1 µL L−1 did not affect the microbial growth at RH = 95%, but 1 µL L−1 reduced the production of AFs by ∼50%. All AITC treatments reduced the fungal population and AFs to undetectable levels at RH = 85%. None of the concentrations altered sensory characteristics of Brazil nuts.CONCLUSIONGaseous AITC could be used as an alternative to inhibit the growth of A. parasiticus during storage and transport of Brazil nuts. © 2017 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Characterization of a Deinococcus radiodurans MazF: A UACA‐specific RNA endoribonuclease
Authors: Miyamoto Tatsuki , Ota Yuri , Yokota Akiko , Suyama Tetsushi , Tsuneda Satoshi , Noda Naohiro 
Published: July 2017

AbstractMicrobes are known to withstand environmental stresses by using chromosomal toxin–antitoxin systems. MazEF is one of the most extensively studied toxin–antitoxin systems. In stressful environments, MazF toxins modulate translation by cleaving single‐stranded RNAs in a sequence‐specific fashion. Previously, a chromosomal gene located at DR0417 in Deinococcus radiodurans was predicted to code for a MazF endoribonuclease (MazFDR0417); however, its function remains unclear. In the present study, we characterized the molecular function of MazFDR0417. Analysis of MazFDR0417‐cleaved RNA sites using modified massively parallel sequencing revealed a unique 4‐nt motif, UACA, as a potential cleavage pattern. The activity of MazFDR0417 was also assessed in a real‐time fluorometric assay, which revealed that MazFDR0417 strictly recognizes the unique tetrad UACA. This sequence specificity may allow D. radiodurans to alter its translation profile and survive under stressful conditions.
Development of patient‐controlled respiratory gating system based on visual guidance for magnetic‐resonance image‐guided radiation therapy
Authors: Kim Jung‐in , Lee Hanyoung , Wu Hong‐Gyun , Chie Eui Kyu , Kang Hyun‐Cheol , Park Jong Min 
Published: July 2017

PurposeThe aim of this study is to develop a visual guidance patient‐controlled (VG‐PC) respiratory gating system for respiratory‐gated magnetic‐resonance image‐guided radiation therapy (MR‐IGRT) and to evaluate the performance of the developed system.MethodsThe near‐real‐time cine planar MR image of a patient acquired during treatment was transmitted to a beam projector in the treatment room through an optical fiber cable. The beam projector projected the cine MR images inside the bore of the ViewRay system in order to be visible to a patient during treatment. With this visual information, patients voluntarily controlled their respiration to put the target volume into the gating boundary (gating window). The effect of the presence of the beam projector in the treatment room on the image quality of the MRI was investigated by evaluating the signal‐to‐noise ratio (SNR), uniformity, low‐contrast detectability, high‐contrast spatial resolution, and spatial integrity with the VG‐PC gating system. To evaluate the performance of the developed system, we applied the VG‐PC gating system to a total of seven patients; six patients received stereotactic ablative radiotherapy (SABR) and one patient received conventional fractionated radiation therapy.ResultsThe projected cine MR images were visible even when the room light was on. No image data loss or additional time delay during delivery of image data were observed. Every indicator representing MRI quality, including SNR, uniformity, low‐contrast detectability, high‐contrast spatial resolution, and spatial integrity exhibited values higher than the tolerance levels of the manufacturer with the VG‐PC gating system; therefore, the presence of the VG‐PC gating system in the treatment room did not degrade the MR image quality. The average beam‐off times due to respiratory gating with and without the VG‐PC gating system were 830.3 ± 278.2 s and 1264.2 ± 302.1 s respectively (P = 0.005). Consequently, the total treatment times excluding the time for patient setup with and without the VG‐PC gating system were 1453.3 ± 297.3 s and 1887.2 ± 469.6 s, respectively, on average (P = 0.005). The average number of beam‐off events during whole treatment session was reduced from 457 ± 154 times to 195 ± 90 times by using the VG‐PC gating system (P < 0.001).ConclusionsThe developed system could improve treatment efficiency when performing respiratory‐gated MR‐IGRT. The VG‐PC gating system could be applied to any kind of bore‐type radiotherapy machine.
Optimization of dual‐energy CT acquisitions for proton therapy using projection‐based decomposition
Authors: Vilches‐Freixas Gloria , Létang Jean Michel , Ducros Nicolas , Rit Simon 
Published: July 2017

PurposeDual‐energy computed tomography (DECT) has been presented as a valid alternative to single‐energy CT to reduce the uncertainty of the conversion of patient CT numbers to proton stopping power ratio (SPR) of tissues relative to water. The aim of this work was to optimize DECT acquisition protocols from simulations of X‐ray images for the treatment planning of proton therapy using a projection‐based dual‐energy decomposition algorithm.MethodsWe have investigated the effect of various voltages and tin filtration combinations on the SPR map accuracy and precision, and the influence of the dose allocation between the low‐energy (LE) and the high‐energy (HE) acquisitions. For all spectra combinations, virtual CT projections of the Gammex phantom were simulated with a realistic energy‐integrating detector response model. Two situations were simulated: an ideal case without noise (infinite dose) and a realistic situation with Poisson noise corresponding to a 20 mGy total central dose. To determine the optimal dose balance, the proportion of LE‐dose with respect to the total dose was varied from 10% to 90% while keeping the central dose constant, for four dual‐energy spectra. SPR images were derived using a two‐step projection‐based decomposition approach. The ranges of 70 MeV, 90 MeV, and 100 MeV proton beams onto the adult female (AF) reference computational phantom of the ICRP were analytically determined from the reconstructed SPR maps.ResultsThe energy separation between the incident spectra had a strong impact on the SPR precision. Maximizing the incident energy gap reduced image noise. However, the energy gap was not a good metric to evaluate the accuracy of the SPR. In terms of SPR accuracy, a large variability of the optimal spectra was observed when studying each phantom material separately. The SPR accuracy was almost flat in the 30–70% LE‐dose range, while the precision showed a minimum slightly shifted in favor of lower LE‐dose. Photon noise in the SPR images (20 mGy dose) had lower impact on the proton range accuracy as comparable results were obtained for the noiseless situation (infinite dose). Root‐mean‐square range errors averaged over all irradiation angles associated to dual‐energy imaging were comprised between 0.50 mm and 0.72 mm for the noiseless situation and between 0.51 mm and 0.77 mm for the realistic scenario.ConclusionsThe impact of the dual‐energy spectra and the dose allocation between energy levels on the SPR accuracy and precision determined through a projection‐based dual‐energy algorithm were evaluated to guide the choice of spectra for dual‐energy CT for proton therapy. The dose balance between energy levels was not found to be sensitive for the SPR estimation. The optimal pair of dual‐energy spectra was material dependent but on a heterogeneous anthropomorphic phantom, there was no significant difference in range accuracy and the choice of spectra could be driven by the precision, i.e., the energy gap.
Intracellular water preexchange lifetime in neurons and astrocytes
Authors: Yang Donghan M. , Huettner James E. , Bretthorst G. Larry , Neil Jeffrey J. , Garbow Joel R. , Ackerman Joseph J.H. 
Published: July 2017

PurposeTo determine the intracellular water preexchange lifetime, τi, the “average residence time” of water, in the intracellular milieu of neurons and astrocytes. The preexchange lifetime is important for modeling a variety of MR data sets, including relaxation, diffusion‐sensitive, and dynamic contrast–enhanced data sets.MethodsHerein, τi in neurons and astrocytes is determined in a microbead‐adherent, cultured cell system. In concert with thin‐slice selection, rapid flow of extracellular media suppresses extracellular signal, allowing determination of the transcytolemmal‐exchange‐dominated, intracellular T1. With this knowledge, and that of the intracellular T1 in the absence of exchange, τi can be derived.ResultsUnder normal culture conditions, τi for neurons is 0.75 ± 0.05 s versus 0.57 ± 0.03 s for astrocytes. Both neuronal and astrocytic τis decrease within 30 min after the onset of oxygen‐glucose deprivation, with the astrocytic τi showing a substantially greater decrease than the neuronal τi.ConclusionsGiven an approximate intra‐ to extracellular volume ratio of 4:1 in the brain, these data imply that, under normal physiological conditions, an MR experimental characteristic time of less than 0.012 s is required for a nonexchanging, two‐compartment (intra‐ and extracellular) model to be valid for MR studies. This characteristic time shortens significantly (i.e., 0.004 s) under injury conditions. Magn Reson Med 79:1616–1627, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
The mechanism of the reaction between an aziridine and carbon dioxide with no added catalyst
Authors: Phung Chau , Tantillo Dean J. , Hein Jason E. , Pinhas Allan R. 
Published: July 2017

AbstractThe mechanism of the reaction at room temperature between an unactivated 2‐alkyl aziridine and carbon dioxide to generate the corresponding oxazolidinone in glass has been studied. Theoretical calculations suggest that this reaction should not proceed at room temperature in the absence of a catalyst. In cases where a reaction was observed, kinetic studies show that the reaction displays a zero‐order dependence with respect to aziridine, indicating that free aziridine is not involved in the rate‐determining step. An ammonium salt generated in situ acts as a catalyst. The amount of this catalyst is diminutive, which prevented spectroscopic identification, and it is not readily removed from the starting material using chromatography.
Associated inter‐ and intrachain conformational transitions in polystyrene solutions
Authors: Chen Jiao , Sha Ye , Gao Siyang , Teng Chao , Wang Xiaoliang , Zhou Dongshan , Li Linling , Chen Wei , Xue Gi 
Published: July 2017

ABSTRACTUnderstanding the conformational changes of polymeric chains in solutions is an essential and integral part of polymer physics. By increasing the concentration of polymer solutions from dilute to semidilute regime, the critical chain overlapping has been reported at the concentration termed asC*. In this study, the associated inter‐ and intrachain conformational transitions in polystyrene (PS) solutions are reported. By comparing the spectroscopic intensity ratio versus concentration for an intrachain PS system, a break point was observed in good solvent which coincided with the theoretically predictedC*. Moreover, the intrachain conformation showed no obvious change belowC*, while significant collapse started to occur aboveC*. This result reveals a new insight in polymer physics, since traditionally the size of polymer chains is considered to decrease weakly regarding the concentration change in the semidilute regime. It is important to find such an abrupt intrachain conformational transition between the dilute and semidilute solutions and provide the first experimental observation that inter‐ and intrachain conformational transitions are correlated to one the other. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys.2017,55, 1373–1379
Fifty years of herbicide research: comparing the discovery of trifluralin and halauxifen‐methyl
Authors: Epp Jeffrey B , Schmitzer Paul R , Crouse Gary D 
Published: July 2017

AbstractFifty years separate the commercialization of the herbicides trifluralin and halauxifen‐methyl. Despite the vast degree of technological change that occurred over that time frame, some aspects of their discovery stories are remarkably similar. For example, both herbicides were prepared very early in the iterative discovery process and both were developed from known lead compound structures by hypothesis‐driven research efforts without the use of in vitro assays or computer‐aided molecular design. However, there are aspects of the halauxifen‐methyl and trifluralin discovery stories that are substantially different. For example, the chemical technology required for the cost‐effective production of halauxifen‐methyl simply did not exist just two decades prior to its commercial launch. By contrast, the chemical technology required for the cost‐effective production of trifluralin was reported in the chemical literature more than two decades prior to its commercial launch. In addition, changes in regulatory environment since the early 1960s ensured that their respective discovery to commercial launch stories would also differ in substantial ways. Ultimately, the time and cost required to develop and register halauxifen‐methyl demanded a global initial business case while the lower registration hurdles that trifluralin cleared enabled a narrow initial business case mainly focused on the USA. © 2017 Society of Chemical Industry