bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbon Nanocatalysts for Aquathermolysis of Heavy Crude Oil: Insights into Thiophene Hydrodesulfurization
Authors: Guo Kun , Gu Minfen , Yu Zhixin 
Published: September 2016

AbstractVarious carbon nanomaterials, including carbon nanotubes (CNTs), ketjenblack (KB) carbon, and graphene nanoplatelets (GNPs), are investigated as catalysts for the hydrodesulfurization (HDS) reaction in the aquathermolysis of heavy crude oil. XRD and Raman spectroscopy are used to characterize the crystallinity and graphitization of these carbon samples. Their morphologies and structures are determined by TEM. Surface functional groups are analyzed by FTIR spectroscopy, and specific surface area and pore volume are studied by nitrogen adsorption–desorption. To evaluate the HDS activity of carbon nanocatalysts, thiophene is employed as a model compound because its ring structure is commonly present in asphaltene and resin components of heavy crude oil. The reactions are conducted under conditions similar to those of actual reservoir conditions of 120–180 °C and <3 MPa. Reaction parameters, namely, catalyst dosage, temperature, and reaction time, are studied to optimize the HDS performance. Results show that factors such as degree of graphitization and specific surface area play critical roles in the enhanced HDS activity of GNPs and KB compared with that of CNTs. This work opens up the opportunity for the implementation of carbon nanomaterials as sustainable metal‐free catalysts in the in situ upgrading and recovery of heavy crude oil.
Tissue-specific selenium accumulation and toxicity in adult female Xenopus laevis chronically exposed to elevated dietary selenomethionine
Authors: Massé Anita J. , Muscatello Jorgelina R. , Hogan Natacha S. , Janz David M. 
Published: September 2016

Abstract

Selenium (Se) is a developmental toxicant that is also capable of altering the bioenergetic and endocrine status of adult fish. To date, aquatic ecotoxicological research has predominantly focused on the toxic effects of Se in fish, and minimal information has been published related to amphibians. The objective of the present study was to investigate the potential toxicity associated with chronically elevated dietary Se consumption in adult female amphibians utilizing the model species Xenopus laevis. Adult X. laevis females were fed a diet augmented with L-selenomethionine at measured concentrations of 0.7 µg Se/g (control), 10.9 µg Se/g, 30.4 µg Se/g, or 94.2 µg Se/g dry mass for 68 d, after which they were bred with untreated males. Ovary, egg, liver, muscle, and blood samples were collected from female frogs after completion of the exposure period and subsequent breeding to ascertain Se tissue distribution, muscle and liver triglyceride and glycogen levels, and plasma cortisol concentrations. The concentrations of Se measured in female tissues excluding the liver were significantly increased in proportion with dietary intake. No significant differences were observed among treatment groups with respect to biometric indices, energy stores, or stress response of adult female X. laevis after Se exposure, which suggests that this amphibian species is capable of accumulating substantial quantities of this element in their tissues with no adverse effects on fitness. Environ Toxicol Chem 2017;36:1047–1055. © 2016 SETAC
Factors affecting soil moisture spatial variability for a humid forest hillslope
Authors: Gwak Yongseok , Kim Sanghyun 
Published: September 2016

AbstractSoil moisture is an important variable in explaining hydrological processes at hillslope scale. The distribution of soil moisture along a hillslope is related to the spatial distribution of the soil properties, the topography, the soil depth, and the vegetation. In order to investigate the factors affecting soil moisture, various environmental data were collected from a humid forest hillslope in this study. Several factors (the wetness index; the contributing area; the local slope; the soil depth; the composition of sand, silt, and clay; the scaling parameter; the hydraulic conductivity; the tree diameter at breast height; and the total weighted basal area) were evaluated for their effect on soil moisture and its distribution over the hillslope at depths of 10, 30, and 60 cm. Both linear correlation analysis and empirical orthogonal function analysis indicated that the soil texture was a dominant factor in soil moisture distribution. The impact of soil hydraulic conductivity was important for all soil moisture ranges at a depth of 30 cm, but those at 10 and 60 cm were limited to very wet and dry conditions, respectively. The relationships of the various factors with the spatial variability of soil moisture indicated the existence of a threshold soil moisture that is related to the composition of the soil and the factors related to the distribution of water in the study area.
Bessel‐beam illumination in dual‐axis confocal microscopy mitigates resolution degradation caused by refractive heterogeneities
Authors: Chen Ye , Glaser Adam , Liu Jonathan T. C. 
Published: September 2016

One of the main challenges for laser‐scanning microscopy of biological tissues with refractive heterogeneities is the degradation in spatial resolution that occurs as a result of beam steering and distortion. This challenge is particularly significant for dual‐axis confocal (DAC) microscopy, which achieves improved spatial‐filtering and optical‐sectioning performance over traditional confocal microscopy through off‐axis illumination and collection of light with low‐numerical aperture (NA) beams that must intersect precisely at their foci within tissues. DAC microscope image quality is sensitive to positional changes and distortions of these illumination‐ and collection‐beam foci. Previous studies have shown that Bessel beams display improved positional stability and beam quality than Gaussian beams when propagating through tissues with refractive heterogeneities, which suggests that Bessel‐beam illumination may enhance DAC microscopy of such tissues. Here, we utilize both Gaussian and Bessel illumination in a point‐scanned DAC microscope and quantify the resultant degradation in resolution when imaging within heterogeneous optical phantoms and fresh tissues. Results indicate that DAC microscopy with Bessel illumination exhibits reduced resolution degradation from microscopic tissue heterogeneities compared to DAC microscopy with conventional Gaussian illumination.
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Seed density and waterfowl use of rice fields in Camargue, France
Authors: Pernollet Claire A. , Cavallo François , Simpson David , Gauthier‐Clerc Michel , Guillemain Matthieu 
Published: September 2016

ABSTRACTEuropean rice fields provide potential nocturnal foraging habitat to waterfowl during winter. Agricultural practices may influence seed density and accessibility, thereby influencing the extent to which ducks use this managed habitat. To assess the potential influence of post‐harvest stubble‐management practices (i.e., flooding, burning, chopping, disking, plowing, and their combinations) on waste rice and weeds, and to evaluate the link of the latter 2 with nocturnal duck abundance, we conducted an experiment in rice fields of the Camargue, France. We assessed the density of available seeds 3 times across the winter, from harvest in late October to departure of the wintering ducks in early February, over 2 winters (2012–2013, 2013–2014). We monitored nocturnal duck use of the fields during the second year. Initial post‐harvest rice and weed seed densities were positively correlated and highly variable. Mean seed density was not dependent on straw management procedure (i.e., burning, chopping, disking). Average rice density decreased by 89% and weed seed density by 69% between harvest and late winter. Seed depletion rate was dependent on initial seed density, and was greatest in plowed fields for rice. Winter flooding did not significantly affect seed depletion rate but was the main determinant of nocturnal duck use of the fields. Duck numbers were lower in burned fields than in chopped or disked fields. One hectare of rice field could support an average of 43 mallard (Anas platyrhynchos)‐sized ducks/day for the entire wintering season (i.e., 5,202 duck‐energy days/ha) given initial post‐harvest seed densities. Harvested rice fields have a great potential as nocturnal foraging habitat for wintering ducks in the Camargue. Plowing should be avoided and flooding promoted to better allow ducks to use these fields. © 2016 The Wildlife Society.
Treatment of eosinophilic otitis media with pegylated interferon‐α 2a and 2b
Authors: Neff Brian A. , Voss Stephen G. , Carlson Matthew L. , O'Brien Erin K. , Butterfield Joseph H. 
Published: September 2016

Objective/HypothesisEosinophilic otitis media (EOM) is a variant of chronic otitis media that is characterized by the development of thick mucoid middle ear effusion, adult onset bronchial asthma, sinonasal polyposis, and aspirin sensitivity. EOM is typically refractory to corticosteroid therapy and surgical intervention. Pegylated interferon (PEG‐IFN) has effectively treated hypereosinophilic syndrome in clinical trials; however, the efficacy of this medication for EOM treatment remains undefined.Study DesignRetrospective, case series, tertiary academic center.MethodsA retrospective chart review was performed on EOM patients from 2008–2014. A total of 32 patients met the clinical criteria for EOM according to established diagnostic guidelines. Outcomes of all patients with severe, refractory EOM who initiated PEG‐IFN therapy are reported.ResultsEight patients were treated with pegylated interferon‐α 2a or 2b for refractory EOM. Half of the patients had significant side effects with interferon treatment. Three of these were able to continue at a reduced dosage without side effect reoccurrence, and one patient stopped the medication permanently. Four of eight (50%) patients had a complete clinical response with total resolution of otorrhea and normalization of middle ear mucosa, and were able to discontinue corticosteroid treatment. Two patients attempted to stop PEG‐IFN therapy after prolonged symptom remission and had recurrent otorrhea. Both patients had symptom resolution after PEG‐IFN reinitiation.ConclusionsThese data demonstrate that pegylated interferon‐α 2a and 2b therapy may benefit patients with severe, refractory EOM. Further larger studies with long‐term follow‐up are required to validate these early but promising results.Level of Evidence4. Laryngoscope, 127:1208–1216, 2017
Early ototoxic changes in patients with germ cell tumor after first cycle of cisplatin‐based therapy
Authors: Noszek László , Budai Barna , Prekopp Péter , Széchenyi Renáta , Szőnyi Márta , Talpai Szabolcs , Nagyiványi Krisztián , Bíró Krisztina , Géczi Lajos 
Published: September 2016

ObjectiveTo prospectively examine early hearing damage detectable with distortion product otoacoustic emission (DPOAE) after the first cycle of cisplatin treatment of patients with testicular tumor.Study DesignBoth ears of 137 consecutive patients were examined at 0.75 to 8 kHz before (B) and after (A) the first cycle of cisplatin (dose: 100 mg/m2/ 5 days).MethodsThe mean amplitudes (B vs. A) were compared with paired t test at each frequency. Ototoxic changes were considered when an individual amplitude difference (B‐A) > 14 dB at 0.75 Hz or > 7 db at 1 to 8 kHz occurred.ResultsThe mean amplitudes were statistically significantly lower after first cycle at 0.75, 6, and 8 kHz. The majority of patients (96%) presented positive differences (B‐A) in one or both ears; in 85 (62%) cases, the positive difference reached the level of ototoxicity out of which 34 (40%) and 19 (22%) of patients suffered ototoxicity in one or both ears, respectively. The difference between right and left ears in distribution of ototoxic cases was nonsignificant. Forty‐five (33%) and four (3%) patients showed ototoxicity at two or more frequencies in one or both ears, respectively. An increased proportion of ototoxic cases can be seen at 0.75 to 1 kHz and 6 to 8 kHz.ConclusionAfter the first cycle of cisplatin treatment, early ototoxicity occurs in close to two‐thirds of patients, as identified by measuring DPOAE. Therefore, further research for biomarkers is required, which can predict patients at risk in order to avoid an irreversible hearing loss by personalized, preventive therapies.Level of Evidence4. Laryngoscope, 127:1909–1915, 2017
Superabsorbent, High Porosity, PAMPS‐Based Hydrogels through Emulsion Templating
Authors: Kovačič Sebastijan , Silverstein Michael S. 
Published: September 2016

Swell! Superabsorbent, mechanically robust, high‐porosity hydrogels based on poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) have been successfully synthesized by templating within high internal phase emulsions (HIPEs). These hydrogel polyHIPEs (HG‐PHs) exhibit unusually high uptakes of water and of artificial urine through structure‐ and crosslinking‐dependent hydrogel‐swelling‐driven void expansion. An HG‐PH with 3.1 mmol g−1 of highly accessible sulfonic acid groups exhibits a 7 meq NaOH ion exchange capacity per gram polymer and rapid dye absorption. The highly swollen HG‐PHs do not fail at compressive strains of up to 60%, they retain water and recover their shapes upon the removal of stress. Unusually, the dry hydrogels have relatively high compressive moduli and achieve relatively high stresses at 70% strain.
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Enantio‐ and Stereoselective Cyclopolymerization of Hexa‐1,5‐diene Catalyzed by Zirconium Complexes Possessing Optically Active Bis(phenolato) Ligands
Authors: Nakata Norio , Watanabe Takanori , Toda Tomoyuki , Ishii Akihiko 
Published: September 2016

Enantio‐ and stereoselective cyclopolymerization of hexa‐1,5‐diene was achieved by enantiomerically pure dichloro zirconium(IV) pre‐catalysts 2 possessing chiral [OSSO]‐type bis(phenolate) ligands (−)‐1 and (+)‐1 in combination with dried methylaluminoxane (dMAO) as an activator. The corresponding activities were recorded with quite high values up to 1,960 g mmol(2)–1 h–1, which are extremely larger than those of the related complexes. The microstructure analysis for the PMCPs furnished by pre‐catalysts (Λ,S,S)‐2 and (Δ,R,R)‐2 showed good isotacticity factors (α = 75−78%) and relatively high proportions of trans‐cyclopentane rings (σ = 14−21%). These enantiomeric PMCPs exhibited large specific optical rotations ([α]D = +28 to +32° from (Λ,S,S)‐2, −26 to −34° from (Δ,R,R)‐2).
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Copper‐Coated Liquid‐Crystalline Elastomer via Bioinspired Polydopamine Adhesion and Electroless Deposition
Authors: Frick Carl P. , Merkel Daniel R. , Laursen Christopher M. , Brinckmann Stephan A. , Yakacki Christopher M. 
Published: September 2016

This study explores the functionalization of main‐chain nematic elastomers with a conductive metallic surface layer using a polydopamine binder. Using a two‐stage thiol‐acrylate reaction, a programmed monodomain is achieved for thermoreversible actuation. A copper layer (≈155 nm) is deposited onto polymer samples using electroless deposition while the samples are in their elongated nematic state. Samples undergo 42% contraction when heated above the isotropic transition temperature. During the thermal cycle, buckling of the copper layer is seen in the direction perpendicular to contraction; however, transverse cracking occurs due to the large Poisson effect experienced during actuation. As a result, the electrical conductivity of the layer reduced quickly as a function of thermal cycling. However, samples do not show signs of delamination after 25 thermal cycles. These results demonstrate the ability to explore multifunctional liquid‐crystalline composites using relatively facile synthesis, adhesion, and deposition techniques.image
Heteroatomic Conjugated Polymers and the Spectral Tuning of Electroluminescence via a Supramolecular Coordination Strategy
Authors: Lin Jinyi , Liu Bin , Yu Mengna , Xie Linghai , Zhu Wensai , Ling Haifeng , Zhang Xinwen , Ding Xuehua , Wang Xuhua , Stavrinou Paul N. , Wang Jianpu , Bradley Donal D. C. , Huang Wei 
Published: September 2016

The unique electronic structures of heteroatomic conjugated polymers (HCPs) offer an attractive platform to tune optoelectronic properties via a supramolecular coordination strategy. This study reports on an sp2 nitrogen heteroatom containing fluorene‐based copolymer namely poly(9,9‐dioctylfluorene‐co‐9,9‐dioctyldiazafluoren‐2,7‐yl) (PF8‐co‐DAF8), with ≈20% DAF8 units. Tuning the optoelectronic properties of PF8‐co‐DAF8 via supramolecular coordination with a Lewis acid (B(C6F5)3 or AlCl3) is explored. Formation of either the PF8‐co‐DAF8‐B(C6F5)3 or PF8‐co‐DAF8‐AlCl3 adducts reduces the optical gap and causes an attendant redshift of the photoluminescence spectra. Controlling the degree and strength of the coordination allows the emission color to be tuned from blue through to green and yellow. This strategy is successfully implemented for polymer light‐emitting diodes, confirming the large degree of spectral tuning whilst maintaining good device performance. Maximum luminous efficiencies, η ≈ 1.55 cd A−1@ 2120 cd m−2, 1.32 cd A−1@ 1424 cd m−2, and 2.56 cd A−1@ 910 cd m−2 are, respectively, recorded for the blue‐emitting diodes with Commission Internationale de L'Eclairage (CIE) (x, y) coordinates = (0.16, 0.16), the white‐emitting diodes with CIE (x, y) = (0.28, 0.38) and the green‐emitting diodes with CIE (x, y) = (0.33, 0.52). The results highlight the versatility of the supramolecular coordination strategy in modifying the electronic structure of HCPs.
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Ultrafast Preparation of AIE‐Active Fluorescent Organic Nanoparticles via a “One‐Pot” Microwave‐Assisted Kabachnik–Fields Reaction
Authors: Long Zi , Liu Meiying , Wan Qing , Mao Liucheng , Huang Hongye , Zeng Guangjian , Wan Yiqun , Deng Fengjie , Zhang Xiaoyong , Wei Yen 
Published: September 2016

The development of effective strategies for fabrication of fluorescent organic nanoparticles (FONs) with an aggregation‐induced emission (AIE) feature has an important impact on the biomedical applications of these AIE‐active FONs. In the current work, an ultrafast strategy for fabricating AIE‐active FONs is developed through a “one‐pot” microwave‐assisted, catalysts‐free, and solvent‐free Kabachnik–Fields (KF) reaction for the first time. It is demonstrated that such organophosphorous‐containing AIE‐active block polymers can be synthesized within 2 min under air atmosphere through the microwave‐assisted KF reaction. These polymers show amphiphilic properties and can self‐assemble into mPEG‐CHO‐Phe‐NH2‐DEP FONs, which display high water dispersibility and desirable optical properties. Biological evaluation results suggest that the mPEG‐CHO‐Phe‐NH2‐DEP FONs exhibit low toxicity and are potential for biological imaging applications. More importantly, many other multifunctional AIE‐active FONs can also be fabricated through the strategy described in this work owing to the universality of KF reaction. Besides, combined with the excellent properties of mPEG‐CHO‐Phe‐NH2‐DEP FONs, it is believed that such microwave‐assisted KF reaction shall be an effective route for designing various AIE‐active nanomaterials for different biomedical applications.
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Functionalization of Planet–Satellite Nanostructures Revealed by Nanoscopic Localization of Distinct Macromolecular Species
Authors: Rossner Christian , Roddatis Vladimir , Lopatin Sergei , Vana Philipp 
Published: September 2016

The development of a straightforward method is reported to form hybrid polymer/gold planet–satellite nanostructures (PlSNs) with functional polymer. Polyacrylate type polymer with benzyl chloride in its backbone as a macromolecular tracer is synthesized to study its localization within PlSNs by analyzing the elemental distribution of chlorine. The functionalized nanohybrid structures are analyzed by scanning transmission electron microscopy, electron energy loss spectroscopy, and spectrum imaging. The results show that the RAFT (reversible addition–fragmentation chain transfer) polymers' sulfur containing end groups are colocalized at the gold cores, both within nanohybrids of simple core–shell morphology and within higher order PlSNs, providing microscopic evidence for the affinity of the RAFT group toward gold surfaces.
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Ultrasound versus MRI in common fibular neuropathy
Authors: Bignotti Bianca , Assini Andrea , Signori Alessio , Martinoli Carlo , Tagliafico Alberto 
Published: September 2016

ABSTRACTIntroductionWe prospectively compared ultrasound (US) and MRI in patients with common fibular neuropathy.MethodsForty adult patients with clinical suspicion of common fibular neuropathy and 40 healthy controls underwent both US and MRI. US and MRI datasets were randomized for prospective reading.ResultsThe overall sensitivity of US and MRI for diagnosing fibular neuropathy was 90% (95% confidence interval [CI], 79.7%‐97.3%) and 87.5% (95% CI, 71.55%‐93.1%), respectively. The overall specificity of US and MRI was 92% (95% CI, 77.45%‐96.1%) and 85% (95% CI, 73.3%‐94.4%), respectively. The overall sensitivity and specificity of US combined with MRI were 94% (95% CI, 0.80%‐0.99%) and 84% (95% CI, 0.70%‐0.91%), respectively. Overall intra‐ and inter‐observer agreements among 3 readers were 0.76% (95% CI, 0.62%‐0.85%) and 0.74% (95% CI, 0.65%‐0.81%).ConclusionsUS diagnostic accuracy for common fibular neuropathy was slightly higher than that of MRI. Muscle Nerve 55: 849–857, 2017
In situ sulfurization to generate Sb2(Se1 − xSx)3 alloyed films and their application for photovoltaics
Authors: Yang Bo , Qin Sikai , Xue Ding‐jiang , Chen Chao , He Yi‐su , Niu Dongmei , Huang Han , Tang Jiang 
Published: September 2016

AbstractBecause of its tunable band gap and band position, Sb2(Se1 − xSx)3 (0 ≤ x ≤ 1) is a promising light‐absorbing material for photovoltaic device applications. However, no systematic study on the synthesis and characterization of single‐phase polycrystalline Sb2(Se1 − xSx)3 thin films has been reported. Through introducing in situ sulfurization into the rapid thermal evaporation process, a series of single‐phase, highly crystalline Sb2(Se1 − xSx)3 films with x = 0.09, 0.20, 0.31, and 0.43 were successfully obtained, with the corresponding band gap, band position and film morphology fully revealed. Futhermore, solar cells with superstrate ITO/CdS/Sb2(Se1 − xSx)3/Au structure were fabricated and carefully optimized. Finally, a champion device having 5.79% solar conversion efficiency was obtained employing uniform Sb2(Se0.80S0.20)3 absorber layer. Our experimental investigation confirmed that Sb2(Se1 − xSx)3 is indeed a very promising absorber material worth further optimization. Copyright © 2016 John Wiley & Sons, Ltd.
Nano‐structured Magnesium Oxide as Efficient Recyclable Catalyst for Knoevenagel and Claisen‐Schmidt Condensation Reactions
Authors: Roy Biplab , Roy Anupam Singha , Panda Asit B. , Islam Sk.Manirul , Chattopadhyay Asoke P. 
Published: September 2016

AbstractNano‐structured magnesium oxide was prepared by calcining its hydromagnesite phase, obtained by simple precipitation using magnesium acetate and ammonium carbonate under ambient condition. This MgO was used as active and reusable catalyst for the Knoevenagel condensation of aromatic aldehydes with malononitrile and ethylcyanoacetate under solvent‐free conditions at room temperature. It also exhibits strong activity in solvent‐free base catalyzed Claisen‐Schmidt condensation of various substituted benzaldehydes with acetophenone. The basic sites of different strengths like surface hydroxyl groups, and low coordination O2− sites may be responsible for the above catalytic activity. The experimental results showed that the nano‐MgO has high catalytic activity and can be recycled without significant loss of its activity.