bluuebunny/crossref_metadata_2025 huggingface dataset:
NiNbO catalyst deposited on anodized aluminum monoliths for the oxidative dehydrogenation of ethane
Authors: Santander José A. , Boldrini Diego E. , Pedernera Marisa N. , Tonetto Gabriela M.
Published: January 2017

Aluminum monoliths were used as substrates to prepare structured catalysts. A rough alumina layer was generated on the surface of the substrates by anodizing followed by hydrothermal treatments. The dip‐coating technique was used for coating the monolithic substrates. Aqueous suspensions with 0.15 and 0.30 g/g of Ni‐Nb mixed oxides catalysts were prepared for that purpose. Colloidal SiO2 was added as a binder in order to obtain homogeneous and adherent coatings. The samples were characterized by SEM, TPR, XPS, XRD, and N2 adsorption and tested in the oxidative dehydrogenation (ODH) of ethane to ethylene. The silica particles produced a drop in catalytic activity without affecting ethylene selectivity. The former effect was attributed mainly to a decrease in surface nickel concentration and an increase in reduction temperature. The presence of anodized aluminum substrates in the reaction environment did not have a significant influence on catalytic activity and product distribution, as observed for the coated monoliths used in this work, thus being a useful material to prepare structured catalysts for low‐temperature ethane ODH.
Structural Basis of the Interaction of Cyclin‐Dependent Kinase 2 with Roscovitine and Its Analogues Having Bioisosteric Central Heterocycles
Authors: Nekardová Michaela , Vymětalová Ladislava , Khirsariya Prashant , Kováčová Silvia , Hylsová Michaela , Jorda Radek , Kryštof Vladimír , Fanfrlík Jindřich , Hobza Pavel , Paruch Kamil
Published: January 2017

The structural basis for the interaction of roscovitine and analogues containing 13 different bioisosteric central heterocycles with the enzyme cyclin‐dependent kinase 2 (CDK2) is elucidated. Although all the central scaffolds are very similar to the purine core of roscovitine, the experimentally determined IC50 values of the inhibitors span three orders of magnitude. By using an extensive computational chemistry approach, the affinities of the inhibitors to CDK2 are determined as calculated binding scores of complexes of the inhibitors with the protein. The interactions of the inhibitors with CDK2 are computationally described by using a hybrid quantum mechanics/semi‐empirical quantum mechanics method (QM/SQM), which combines the DFT‐D method for the QM part and the PM6‐D3H4X method for the SQM part. The solvent effect is described by the COSMO implicit solvation model at the SQM level for the whole system. The contributions of the scaffolds and the individual substituents, quantified and evaluated in relation to conformations of optimized protein–inhibitor complexes, are found not to be simply additive. The inhibitory activity of the selected candidates, including two newly prepared compounds, is tested against CDK2. The results of the calculations are in close agreement with the experimental data.
Mutational screening of GLI3, SHH, preZRS, and ZRS in 102 Chinese children with nonsyndromic polydactyly
Authors: Xiang Ying , Jiang Limin , Wang Bo , Xu Yunlan , Cai Haiqing , Fu Qihua
Published: January 2017

Background: Polydactyly is a group of congenital limb malformations that show high degree of phenotypic variability and genetic heterogeneity. Results: In the present study, four genomic regions (exons of GLI3, SHH, and noncoding sequences of preZRS and ZRS) involved in hedgehog (Hh) signaling pathway were sequenced for 102 unrelated Chinese children with nonsyndromic polydactyly. Two GLI3 variants (c.2844 G > G/A; c.1486C > C/T) and four preZRS variants (chr7:156585336 A>G; chr7:156585421 C>A; chr7: 156585247 G>C; chr7:156585420 A > C) were observed in 2(2.0%) and 6(5.9%) patients, respectively. These variants are not over‐represented in the Chinese healthy population. All the 8 cases showed preaxial polydactyly in hands. Additionally, no specific patterns of malformation predicted mutations in other candidate genes or sequences. Conclusions: This is the first report of the assessment of the frequency of GLI3/SHH/preZRS/ZRS in Chinese patients to show any higher possibility of mutations or variants for the 4 genes or sequences in China. Developmental Dynamics 246:392–402, 2017. © 2017 Wiley Periodicals, Inc.
Can community structure track sea‐level rise? Stress and competitive controls in tidal wetlands
Authors: Schile Lisa M. , Callaway John C. , Suding Katharine N. , Kelly N. Maggi
Published: January 2017

Climate change impacts, such as accelerated sea‐level rise, will affect stress gradients, yet impacts on competition/stress tolerance trade‐offs and shifts in distributions are unclear. Ecosystems with strong stress gradients, such as estuaries, allow for space‐for‐time substitutions of stress factors and can give insight into future climate‐related shifts in both resource and nonresource stresses. We tested the stress gradient hypothesis and examined the effect of increased inundation stress and biotic interactions on growth and survival of two congeneric wetland sedges, Schoenoplectus acutus and Schoenoplectus americanus. We simulated sea‐level rise across existing marsh elevations and those not currently found to reflect potential future sea‐level rise conditions in two tidal wetlands differing in salinity. Plants were grown individually and together at five tidal elevations, the lowest simulating an 80‐cm increase in sea level, and harvested to assess differences in biomass after one growing season. Inundation time, salinity, sulfides, and redox potential were measured concurrently. As predicted, increasing inundation reduced biomass of the species commonly found at higher marsh elevations, with little effect on the species found along channel margins. The presence of neighbors reduced total biomass of both species, particularly at the highest elevation; facilitation did not occur at any elevation. Contrary to predictions, we documented the competitive superiority of the stress tolerator under increased inundation, which was not predicted by the stress gradient hypothesis. Multifactor manipulation experiments addressing plant response to accelerated climate change are integral to creating a more realistic, valuable, and needed assessment of potential ecosystem response. Our results point to the important and unpredicted synergies between physical stressors, which are predicted to increase in intensity with climate change, and competitive forces on biomass as stresses increase.
Forest cover change and water yield in large forested watersheds: A global synthetic assessment
Authors: Li Qiang , Wei Xiaohua , Zhang Mingfang , Liu Wenfei , Fan Houbao , Zhou Guoyi , Giles‐Hansen Krysta , Liu Shirong , Wang Yi
Published: January 2017

The effects of forest cover change on water yield have long been studied across the globe. Several reviews have summarized the impacts of forest change and water yield from the small and paired watershed experiments, but no any synthetic assessment has been conducted on the basis of studies of large watersheds (>1,000 km2). We conducted a synthetic analysis on the basis of the studies from 162 large studied watersheds across the globe to explore how forest cover change affects annual water yield. Our first‐ever assessment confirms that deforestation increases annual water yield and reforestation decreases it, which is consistent with results from paired watershed experiments. More importantly, we found that forest cover and climate variability play a coequal role in annual water yield variations. The effects of forest cover change and climate variability on annual water yield variations can be additive or offsetting. Thus, their interactions can critically determine the magnitudes and directions of water yield changes. We also found that the hydrological sensitivities to forest cover change in smaller and dryer watersheds are higher than those in larger and wetter ones. The implications of these findings for sustainable water and watershed management are discussed in the context of future land cover and climate changes.
Examining gradients in ecosystem novelty: fish assemblage structure in an invaded Everglades canal system
Authors: Gandy David A. , Rehage Jennifer S.
Published: January 2017

Novel ecosystems result from a combination of altered historical abiotic regimes and new species assemblages. In freshwater systems, novel environmental conditions often result from large‐scale changes to hydrological connectivity as well as species invasions. Novel environmental conditions may affect the survival of aquatic fauna by altering dispersal patterns and resource fluctuations, and/or may impose physiological constraints on native species evolutionarily adapted to particular environments. Further, novel systems can provide insight into processes driving community structure because re‐sorting or filtering of regional biota is a likely consequence of decoupling from historical conditions. Although several studies document the presence of novel conditions, few examine variation or gradients in novelty. The Florida Everglades is a highly invaded and hydrologically altered system characterized by a large network of canals that compartmentalize the ecosystem and act to both increase and decrease connectivity. Little is known about how canals in this region function as habitat for native and nonnative fishes, the extent to which these canals may function as novel habitats, and how these habitat characteristics may influence distribution, abundance, and assembly patterns. In this study, we examined native and nonnative fish assemblages along a gradient of novelty, defined as the loss of wetland connectivity, influence of the natural hydrological regime, and habitat complexity (well connected to leveed canals). As novelty increased, native species richness and abundance strongly declined and the contribution of nonnatives increased to nearly 50%. Vast differences in community structure across the novelty gradient were strongly influenced by spatial factors and secondarily by hydrological factors, while habitat and abiotic factors were of very low relevance. Natives and nonnatives had opposing responses to key hydrological and habitat characteristics. Abundance of native fishes declined with decreased connectivity to adjacent marshes and canal littoral zone width, while nonnative fishes increased significantly in the most novel canals. Our results suggest that the inherent loss of natural environmental conditions and subsequent replacement by novel ones can lead to extensive changes in fish community structure. Success or failure at maintaining native assemblages will rely heavily on natural resource manager's ability to incorporate natural environmental characteristics with ecosystem restoration.
Temporal variability in large grazer space use in an experimental landscape
Authors: Raynor Edward J. , Joern Anthony , Skibbe Adam , Sowers Mark , Briggs John M. , Laws Angela N. , Goodin Douglas
Published: January 2017

Land use, climate change, and their interaction each have great potential to affect grazing systems. With anticipated more frequent and extensive future drought, a more complete understanding of the mechanisms that determine large grazer landscape‐level distribution under varying climatic conditions is integral to ecosystem management. Using an experimental setting with contrasting fire treatments, we describe the inter‐annual variability of the effect of landscape topography and disturbance from prescribed spring fire on large grazer space use in years of variable resource availability. Using GPS telemetry, we investigated space use of plains bison (Bison bison bison) as they moved among watersheds managed with variable experimental burn treatments (1‐, 2‐, 4‐, and 20‐year burn intervals) during a seven‐year period spanning years of average‐to‐above average forage production and severe drought. At the landscape scale, bison more strongly favored high‐elevation and recently burned watersheds with watersheds burned for the first time in 2 or 4 yr consistently showing higher use relative to annually burned watersheds. In particular, watersheds burned for the first time in 4 yr were avoided to lesser extent than other more frequently burned watersheds during the dormant season. This management type also maintained coupling between bison space use and post‐fire regrowth across post‐drought growing season months, whereas watersheds with more frequent fire‐return intervals attracted bison in only the first month post‐fire. Hence, fire frequency played a role in maintaining the coupling of grazer and post‐fire regrowth, the fire–grazer interaction, in response to drought‐induced reduction in fuel loads. Moreover, bison avoided upland habitat in poor forage production years, when forage regrowth is less likely to occur in upland than in lowland habitats. Such quantified responses of bison to landscape features can aid future conservation management efforts and planning to sustain fire–grazer interactions and resulting spatial heterogeneity in grassland ecosystems.
Can niche plasticity promote biodiversity–productivity relationships through increased complementarity?
Authors: Niklaus Pascal A. , Baruffol Martin , He Jin‐Sheng , Ma Keping , Schmid Bernhard
Published: January 2017

Most experimental biodiversity–ecosystem functioning research to date has addressed herbaceous plant communities. Comparably little is known about how forest communities will respond to species losses, despite their importance for global biogeochemical cycling. We studied tree species interactions in experimental subtropical tree communities with 33 distinct tree species mixtures and one, two, or four species. Plots were either exposed to natural light levels or shaded. Trees grew rapidly and were intensely competing above ground after 1.5 growing seasons when plots were thinned and the vertical distribution of leaves and wood determined by separating the biomass of harvested trees into 50 cm height increments. Our aim was to analyze effects of species richness in relation to the vertical allocation of leaf biomass and wood, with an emphasis on bipartite competitive interactions among species. Aboveground productivity increased with species richness. The community‐level vertical leaf and wood distribution depended on the species composition of communities. Mean height and breadth of species‐level vertical leaf and wood distributions did not change with species richness. However, the extra biomass produced by mixtures compared to monocultures of the component species increased when vertical leaf distributions of monocultures were more different. Decomposition of biodiversity effects with the additive partitioning scheme indicated positive complementarity effects that were higher in light than in shade. Selection effects did not deviate from zero, irrespective of light levels. Vertical leaf distributions shifted apart in mixed stands as consequence of competition‐driven phenotypic plasticity, promoting realized complementarity. Structural equation models showed that this effect was larger for species that differed more in growth strategies that were characterized by functional traits. In 13 of the 18 investigated two‐species mixtures, both species benefitted relative to intraspecific competition in monoculture. In the remaining five pairwise mixtures, the relative yield gain of one species exceeded the relative yield loss of the other species, resulting in a relative yield total (RYT) exceeding 1. Overall, our analysis indicates that richness–productivity relationships are promoted by interspecific niche complementarity at early stages of stand development, and that this effect is enhanced by architectural plasticity.
Field‐Supported Slow Magnetic Relaxation in Hexacoordinate CoII Complexes with Easy Plane Anisotropy
Authors: Rajnák Cyril , Titiš Ján , Moncoľ Ján , Renz Franz , Boča Roman
Published: January 2017

Two mononuclear cobalt(II) complexes containing four equatorial 4‐benzylpyridine and two axial chlorido and/or thiocyanato ligands {[Co[L]4X2]; X = Cl or NCS} possess easy plane magnetic anisotropy, as determined by magnetic susceptibility and magnetization analyses, and confirmed by ab initio calculations (D = +106 and +95 cm–1). AC susceptibility measurements show a slow magnetic relaxation with two or three relaxation branches. The low‐frequency pathway occurs at about 1–10 Hz, and it disappears progressively upon heating. The high‐frequency mode exists at frequency ranges above 500 Hz. The characteristics of these field‐induced single‐molecule magnets strongly depend upon the applied magnetic field, which causes a prolongation of the low‐frequency relaxation time and a shortening of the high‐frequency one. At 1.0 T and 1.9 K the relaxation time for the low‐frequency pathway is as slow as 756 or 164 ms for X = Cl or X = NCS, respectively.
Evidence on the Nature of the Active Oxidants Involved in the Oxidation of Alcohols with Oxone Catalyzed by an Electron‐Deficient Manganese Porphyrin: A Combined Kinetic and Mechanistic Study
Authors: Nasrollahi Rahele , Zakavi Saeed
Published: January 2017

A study of the kinetics and mechanism of the oxidation of a series of electron‐rich and electron‐deficient benzyl alcohols and cyclohexanol with high‐valent manganese oxo species formed by the reaction of meso‐tetrakis(2,6‐dichlorophenyl)porphyrinatomanganese(III) acetate [Mn(TDClPP)(OAc)] and tetra‐n‐butylammonium oxone (TBAO) in the presence of imidazole (ImH) are reported. The use of Mn(TDClPP)(OAc), ImH, and TBAO in a 1:15:1000 molar ratio led to the exclusive formation of [(ImH)MnV(O)(TDClPP)]+ (λmax = 408 nm), whereas a mixture of [(ImH)MnV(O)(TDClPP)]+, (ImH)MnIV(O)(TDClPP) (λmax = 421 nm), and (ImH)(peroxymonopersulfate)MnIII(TDClPP) (λmax = 473 nm) was observed for molar ratios lower than this. The formation of [(ImH)MnV(O)(TDClPP)]+ and (ImH)MnIV(O)(TDClPP) from the catalyst precursor was evidenced in the UV/Vis absorption spectrum of the intermediates at 273 K in dichloromethane. Owing to the different reactivities of the high‐valent intermediates towards the oxidation of alcohols, a biphasic mechanism was observed. The observed (kobs) and second‐order (k2) rate constants of oxygen‐atom transfer from high‐valent MnV(O) species to the substrates were evaluated by monitoring the absorption changes at λ = 473 nm. The Hammett treatment of the oxidation data gave a slope (ϱ) of –0.87, which is consistent with a radical mechanism. Furthermore, a strong correlation between the rate constants and the C–H bond dissociation energies (BDEs) of the alcohols suggests the involvement of H‐atom abstraction in the mechanism of the oxidation reaction. Interestingly, a negative temperature dependence of the reaction rate was observed for the oxidation of benzyl alcohol from 273 to 298 K. Furthermore, the high‐valent MnV(O) and MnIV(O) species may be distinguished through their significantly different activities towards the oxidation of alcohols.
Recyclable Chiral Bifunctional Thioureas Derived from [60]Fullerene and Their Use as Highly Efficient Organocatalysts for the Asymmetric Nitro‐Michael Reaction
Authors: Andrés José M. , González Miguel , Maestro Alicia , Naharro Daniel , Pedrosa Rafael
Published: January 2017

Three novel fullerothioureas derived from natural valine, phenylalanine, and tert‐leucine have been prepared by Prato's reaction of [60]fullerene and the corresponding aldehydes. These hybrids have been used as organocatalysts in a typical stereoselective nitro‐Michael addition reaction under homogeneous and neat conditions. The catalysts are easily recoverable by filtration, and are recyclable for at least five times. The addition products were obtained in excellent yields and stereoselectivities by using catalyst loadings of as low as 0.5 mol‐%.
Potentiometric Determination of Ciprofloxacin in Physiological Fluids Using Carbon Paste and Nano‐Composite Carbon Paste Electrodes
Authors: Abdel‐Haleem Fatehy M. , Rizk Mahmoud S. , Badr Ibrahim H. A.
Published: January 2017

Nano‐composite carbon paste and simple carbon paste based potentiometric sensors were constructed and used for determination of ciprofloxacin at different pH values. Sensors were formulated utilizing graphite, suitable plasticizer, cirprofloxacinium‐phosphotungstate, as well as a highly lipophilic cation‐exchanger, sodium tetrakis(trifluoromethyl)phenyl borate. Effect of the incorporation of multi‐walled carbon nanotubes (MWCNTs) on the response characteristics of the prepared sensors was investigated. Results obtained were compared to that of a PVC‐sensor contains only the cation‐exchanger. In addition, the effect of solutions pH on the response characteristics was also studied; at pH 4.1, the slopes of bare carbon paste and MWCNTs‐based sensors were 55.7 and 66.6 mV/conc.decade in a concentration range of 10−2‐10−5 M with detection limits of 1.0x10−5 and 7.9x10−6 M, respectively. Although both sensors exhibited super‐Nernstian slopes at pH 2.0, the selectivity was improved compared to that measured at pH 4.1. Optimized sensors were successfully applied for the determination of ciprofloxacin in its pure form, pharmaceutical preparations, as well as spiked urine and serum samples, with high recovery.
Techno‐economic evaluation of standalone hybrid solar‐wind systems for small residential districts in the central desert of Iran
Authors: Razmjoo Ali , Qolipour Mojtaba , Shirmohammadi Reza , Heibati S. Mohammadreza , Faraji Iraj
Published: January 2017

Today, it is common knowledge that increased use of renewable energies has a significant impact on reducing greenhouse gas emissions. The most notable types of renewable energies are solar energy and wind energy, whose popularity comes from their prominent features such as cost‐effectiveness, stability and easy utilization. The objective of this paper is to perform a technical–economic analysis on combined utilization of solar and wind power in two cities of Qom and Yazd, to conduct a feasibility study on the construction of clean energy producing power plants in these locations. To achieve this objective, we first gather the required data from the national meteorological organization, and then use Homer software to perform technical and economic analyses on the two considered sites. Solar and wind analyses on Qom and Yazd show that both cities have great potential in solar energy generation, but wind speed data indicate that only Qom has the wind characteristics appropriate for wind power generation. Overall, these results indicate that investments on solar energy sector of both cities will be economically justified, but only Qom has the wind characteristics required to make investments on its wind energy sector economic. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1194–1207, 2017
Utility, reliability, sensitivity and validity of an online test system designed to monitor changes in cognitive function in clinical trials
Authors: Wesnes Keith A. , Brooker Helen , Ballard Clive , McCambridge Laura , Stenton Robert , Corbett Anne
Published: January 2017

Objective

The advent of long‐term remotely conducted clinical trials requires assessments which can be administered online. This paper considers the utility, reliability, sensitivity and validity of an internet‐based system for measuring changes in cognitive function which is being used in one such trial.

Methods

The Platform for Research Online to investigate Genetics and Cognition in Ageing is a 10‐year longitudinal and entirely remote study launched in November 2015. The CogTrackTM System is being used to monitor changes in important aspects of cognitive function using tests of attention, information processing and episodic memory. On study entry, the participants performed CogTrackTM up to three times over seven days, and these data are evaluated in this paper.

Results

During the first six months of the study, 14 531 individuals aged 50 to 94 years enrolled and performed the CogTrackTM System, 8627 of whom completed three test sessions. On the first administration, 99.4% of the study tasks were successfully completed. Repeated testing showed training/familiarisation effects on four of the ten measures which had largely stabilised by the third test session. The factor structure of the various measures was found to be robust. Evaluation of the influence of age identified clinically relevant declines over the age range of the population on one or more measures from all tasks.

Conclusions

The results of these analyses identify CogTrackTM to be a practical and valid method to reliably, sensitively, remotely and repeatedly collect cognitive data from large samples of individuals aged 50 and over. Copyright © 2017 John Wiley & Sons, Ltd.
The effects of low level laser therapy on both HIV‐1 infected and uninfected TZM‐bl cells
Authors: Lugongolo Masixole Yvonne , Manoto Sello Lebohang , Ombinda‐Lemboumba Saturnin , Maaza Malik , Mthunzi‐Kufa Patience
Published: January 2017

Human immunodeficiency virus (HIV‐1) infection remains a major health problem despite the use of highly active antiretroviral therapy (HAART), which has greatly reduced mortality rates. Due to the unavailability of an effective vaccine and treatment that would completely eradicate the virus in infected individuals, the quest for new therapies continues. Low level laser therapy (LLLT) involves the exposure of cells to low levels of red or infrared light. LLLT has been widely used in different medical conditions, but not in HIV‐1 infection. This study aimed to determine the effects of LLLT on HIV‐1 infected and uninfected TZM‐bl cells. Both infected and uninfected cells were irradiated at a wavelength of 660 nm with different fluences from 2 J/cm2 to 10 J/cm2. Changes in cellular responses were assessed using cell morphology, viability, proliferation, cytotoxicity and luciferase activity assays. Upon data analysis, uninfected irradiated cells showed no changes in cell morphology, viability, proliferation and cytotoxicity, while the infected irradiated cells did. In addition, laser irradiation reduced luciferase activity in infected cells. Finally, laser irradiation had no inhibitory effect in uninfected cells, whereas it induced cell damage in a dose dependent manner in infected cells.

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Synthesis of 3H, 2H4, and 14C‐MK 3814 (preladenant)
Authors: Hesk D. , Borges S. , Dumpit R. , Hendershot S. , Koharski D. , McNamara P. , Ren S. , Saluja S. , Truong V. , Voronin K.
Published: January 2017

MK 3814 is a potent and selective antagonist of the A2a receptor. A2a receptor antagonists have the potential for the treatment of Parkinson disease. Three distinct isotopically labelled forms of MK 3814 were synthesized. [3H]MK 3814 was prepared for a preliminary absorption, distribution, metabolism, and excretion data (ADME) evaluation of the compound and [14C]MK 3814 for more definitive ADME work, including an absorption, metabolism, and excretion study in man. In addition, [2H4]MK 3814 was prepared as an internal standard for a liquid chromatography mass spectrometry bioanalytical method. This paper discusses the synthesis of 3 isotopically labelled forms of MK 3814.
Impact of dianionic and dicationic linkers on tumor uptake and biodistribution of [64Cu]Cu/NOTA peptide‐based gastrin‐releasing peptide receptors antagonists
Authors: Mansour Nematallah , Dumulon‐Perreault Véronique , Ait‐Mohand Samia , Paquette Michel , Lecomte Roger , Guérin Brigitte
Published: January 2017

In this study, we investigated for the first time the influence of 2‐aminoethyl‐piperazine‐1‐carboxylic acid (APCA) and amino‐hexanedioic‐1‐acid (AHDA) on tumor uptake and elimination kinetics of [64Cu]‐radiolabeled gastrin releasing peptide receptors (GRPR) antagonists. Three GRPR antagonists containing the RM26 sequence were synthesized and conjugated with NOTA via different linkers (LK): polyethylene glycol (PEG–neutral), APCA (dicationic) or AHDA (dianionic). The NOTA‐LK‐RM26 peptides were radiolabeled with 64Cu to assess their pharmacokinetic and positron emission tomography (PET) imaging properties using PC3 tumor‐bearing athymic nude mice. The inhibition constants (Ki) of the 3 natCu/NOTA‐LK‐RM26 peptides bearing PEG, dicationic and dianionic linkers were 0.98 ± 0.48 nM, 0.95 ± 0.21 nM, and 17.97 ± 2.79 nM, respectively. The [64Cu] NOTA‐LK‐RM26 conjugates were prepared with labeling yields superior to 95% and specific activities of 67 to 77 TBq/mmol. The 3 radiopeptides were stable in vivo and showed GRPR‐specific uptake in pancreas with a very fast washout of this tissue observed for [64Cu]‐NOTA‐AHDA‐RM26 peptide. Results from imaging studies displayed specific PC3 tumor uptake for both [64Cu]‐NOTA‐APCA‐ and AHDA‐RM26, similar kidney elimination and fast liver washout. Considering their adequate imaging characteristics, [64Cu]‐NOTA‐LK‐RM26 bearing APCA‐ and AHDA‐linkers are promising candidates for GRPR‐targeted PET imaging prostate cancer.
Observed precipitation trend changes in the western Mediterranean region
Authors: Valdes‐Abellan J. , Pardo M.A. , Tenza‐Abril A.J.
Published: January 2017

This paper analyses the daily precipitation data recorded for the last 75–80 years in SE Spain. Prior to statistical analysis, homogeneity tests were performed to determine the usefulness of the data (recorded in six pluviometric stations). If the data were homogeneous, the Mann–Kendall test was performed to detect monotonic trends for variables such as total precipitation, number of days with precipitation greater than 1, 20 or 40 mm, number of consecutive dry days and number of consecutive wet days. Moreover, the linear tendency was calculated and accepted (or rejected) by performing a Student's t‐test of the calculated residual values. The results showed, on average, a clear change in precipitation patterns for the last 20 years. Annual rainfall had decreased, with values ranging from 0 to 15%, dry periods had increased in length, and the number of rainy days had decreased (especially when high daily precipitation was considered). This latter notion did not exactly concur with the conclusions of the Intergovernmental Panel on Climate Change (IPCC) 2014 Synthesis Report related to the study area.
Coupling effect on charge‐transfer mechanism of surface‐enhanced resonance Raman scattering
Authors: Li Quanjiang , Wang Jingang , Ding Qianqian , Chen Maodu , Ma Fengcai
Published: January 2017

In this work, charge‐transfer mechanism of surface‐enhanced resonance Raman scattering (SERRS) spectroscopy of pyrazine absorbed on Ac@Au7 clusters is theoretically investigated, and the coupling effect between the nanoparticles is especially concerned. First, the contributions of coupling effect to surface‐enhanced Raman scattering (SERS) are compared between the ground‐state nanoparticles. Second, the visualization of charge transfer provides evidence for the coupling effect on the charge‐transfer enhancement mechanism of SERRS spectroscopy. The theoretical results show that the coupling effect on charge‐transfer mechanism of SERRS can significantly enhance the intensity of SERS spectra up to about 6 × 105 times. The different coupling ways not only result in different degree of charge transfer on electronic transitions, but also cause different intensity of charge‐transfer absorption peaks. Both of them strongly influence the enhancement of charge‐transfer mechanism of SERRS. This study promotes the understanding of charge‐transfer enhancement mechanism of SERRS for ultrasensitive Raman spectral analysis at nanoscale. Copyright © 2017 John Wiley & Sons, Ltd.
Raman microspectroscopic studies of unirradiated homogeneous (U0.76Pu0.24)O2+x: the effects of Pu content, non‐stoichiometry, self‐radiation damage and secondary phases
Authors: Talip Zeynep , Peuget Sylvain , Magnin Magali , Berardo Lydie , Valot Christophe , Vauchy Romain , Jégou Christophe
Published: January 2017

In this study, micro‐Raman spectroscopy technique was implemented to characterize an unirradiated homogeneous Gigondas (U0.76Pu0.24)O2+x sample, which had been stored for 30 years at room temperature under air. The impacts of Pu content, deviation from stoichiometry, self‐radiation damage and formation of secondary phases were assessed by comparing the Raman spectra of the aged Gigondas with an annealed sample [(U0.76Pu0.24)O2]. The Pu content of the sample was measured by electron probe microanalysis technique, while the stoichiometry of the annealed Gigondas sample was determined by the results of electron probe microanalysis technique and X‐ray diffraction. Two methods were proposed to explain the Raman spectrum of the aged Gigondas sample. They considered the presence of MO2+x phase and the mixture of MO2+x and M4O9 (M: U and Pu) phases respectively. Formation of the secondary phases, which were detected on the surface of the aged Gigondas sample, could be mostly due to alpha radiolysis. It was suggested that self‐radiation damage up to about 0.6 dpa leads to a shift of MO2+x T2g band by about 1 to 2 cm−1 towards lower wavenumbers. Copyright © 2017 John Wiley & Sons, Ltd.
Raman spectroscopy and imaging of Bernal‐stacked bilayer graphene synthesized on copper foil by chemical vapour deposition: growth dependence on temperature
Authors: Fabiane M. , Madito M. J. , Bello A. , Manyala N.
Published: January 2017

We report on the effect of temperature on the growth of bilayer graphene on a copper foil under atmospheric pressure chemical vapour deposition (AP‐CVD). Before characterization of the AP‐CVD bilayer graphene, a high‐quality graphene flake was obtained from the Kish bulk graphite by micro‐mechanical exfoliation and characterized by using Raman spectroscopy and imaging. The Raman data of the exfoliated, high‐quality graphene flake show monolayer and bilayer graphenes and were compared with the Raman data of AP‐CVD graphene. Raman spectroscopy of AP‐CVD graphene shows bilayer films that exhibit predominantly Bernal stacking with an I2D/IG ratio of ~1. At low growth temperature (~780 °C), Raman disorder‐related peak intensity in the AP‐CVD graphene is high and decreases with an increase in growth temperature to the lowest disorder intensity at ~973 °C. The selected area electron diffraction and atomic force microscopy average step height analysis showed the thickness of the bilayer graphene. The AP‐CVD graphene is uniform at low growth temperatures (~780 °C) with a high disorder and becomes non‐uniform at high growth temperatures (~867–973 °C) with a very low disorder as bilayer graphene evolves to form islands with an average lateral size of <10 μm. Competition between carbon adatoms supply through dehydrogenation of the CHx species, mobility and desorption rate of the carbon‐adatom species for nucleation of the bilayer graphene as a function of temperature is elucidated. This study provides further insight into the growth mechanisms of bilayer graphene by AP‐CVD on Cu. Copyright © 2017 John Wiley & Sons, Ltd.
Geometry and topology optimization of sheet metal profiles by using a branch‐and‐bound framework
Authors: Horn B. M. , Lüthen H. , Pfetsch M. E. , Ulbrich S.
Published: January 2017

In this paper well established procedures from partial differential equation (PDE)‐constrained and discrete optimization are combined in a new way to find an optimal design of a multi‐chambered profile. Given a starting profile design, a load case and corresponding design constraints (e.g. sheet thickness, chamber sizes), the aim is to find an optimal subdivision into a predefined number of chambers with optimal shape subject to structural stiffness. In the presented optimization scheme a branch‐and‐bound tree is generated with one additional chamber in each level. Before adding the next chamber, the geometry of the profile is optimized. Then a relaxation of a topology optimization problem is solved. Based on this relaxation, a best fitting feasible topology subject to manufacturability conditions is determined using a new mixed integer method employing shortest paths. To improve the running time, the finite element simulations for the geometry optimization and topology relaxation are performed with different levels of accuracy. Finally, numerical experiments are presented including different starting geometries, load scenarios and mesh sizes.
Ribose operon repressor (RbsR) contributes to the adhesion of Aeromonas hydrophila to Anguilla japonica mucus
Authors: Lin Guifang , Chen Wenbo , Su Yongquan , Qin Yingxue , Huang Lixing , Yan Qingpi
Published: January 2017

The characterization of adhesion between pathogenic bacteria and the host is critical. Pathogenic Aeromonas hydrophila was shown to adhere in vitro to the mucus of Anguilla japonica. To further investigate the adhesion mechanisms of A. hydrophila, a mini‐Tn10 transposon mutagenesis system was used to generate an insertion mutant library by cell conjugation. Seven mutants that were impaired in adhesion to mucus were selected out of 332 individual colonies, and mutant M196 was the most severely impaired strain. National Center for Biotechnology Information (NCBI) blast analysis showed that mutant M196 was inserted by mini‐Tn10 with an ORF of approximately 1,005 bp (GenBank accession numbers KP280172). This ORF is predicted to encode a protein consist of 334 amino acid, which displays the highest identity (98%) with the RbsR of A. hydrophila ATCC 7966. Random inactivation of rbsR gene affected the pleiotropic phenotypes of A. hydrophila. The adhesion ability and the survival level of the rbsR gene mutant (M196) were attenuated compared with the wild‐type and rbsR complementary type. The findings of this study indicated that RbsR plays roles in the bacterial adhesion and intracellular survival of A. hydrophila.
Potential Therapeutic Applications of Adenosine A2A Receptor Ligands and Opportunities for A2A Receptor Imaging
Authors: van Waarde Aren , Dierckx Rudi A. J. O. , Zhou Xiaoyun , Khanapur Shivashankar , Tsukada Hideo , Ishiwata Kiichi , Luurtsema Gert , de Vries Erik F. J. , Elsinga Philip H.
Published: January 2017

Adenosine A2A receptors (A2ARs) are highly expressed in the human striatum, and at lower densities in the cerebral cortex, the hippocampus, and cells of the immune system. Antagonists of these receptors are potentially useful for the treatment of motor fluctuations, epilepsy, postischemic brain damage, or cognitive impairment, and for the control of an immune checkpoint during immunotherapy of cancer. A2AR agonists may suppress transplant rejection and graft‐versus‐host disease; be used to treat inflammatory disorders such as asthma, inflammatory bowel disease, and rheumatoid arthritis; be locally applied to promote wound healing and be employed in a strategy for transient opening of the blood–brain barrier (BBB) so that therapeutic drugs and monoclonal antibodies can enter the brain. Increasing A2AR signaling in adipose tissue is also a potential strategy to combat obesity. Several radioligands for positron emission tomography (PET) imaging of A2ARs have been developed in recent years. This review article presents a critical overview of the potential therapeutic applications of A2AR ligands, the use of A2AR imaging in drug development, and opportunities and limitations of PET imaging in future research.
Some general models of traffic flow in an isolated network
Authors: Jiménez‐Casas Ángela , Rodríguez‐Bernal Aníbal
Published: January 2017

Starting form basic principles, we obtain mathematical models that describe the traffic of material objects in a network represented by a graph. We analyze existence, uniqueness, and positivity of solutions for some implicit models. Also, some linear models and their equilibria are analyzed. Copyright © 2017 John Wiley & Sons, Ltd.
Assessment of small sensory fiber function across the spectrum of severity in carpal tunnel syndrome patients
Authors: Clarke Christopher , Christensen Christopher , Curran Matthew W.T. , Chan K. Ming
Published: January 2017

Introduction: In compressive neuropathies, large myelinated nerve fibers are generally thought to be more susceptible. In this study, we investigated small myelinated Aδ and unmyelinated C fiber function in patients with mild, moderate, and severe carpal tunnel syndrome. Methods: Forty‐four healthy controls and 81 carpal tunnel syndrome patients in the mild, moderate, or severe categories were recruited. Small fiber sensation in the affected hand was determined with quantitative sensory testing. Results: Cold detection thresholds in the severe carpal tunnel syndrome group (18.9 ± 6.8°C) were significantly impaired compared with controls (27.2 ± 2.1°C) (P < 0.01). Similarly, warm detection thresholds were also impaired in the severe carpal tunnel syndrome group (41.2 ± 3.5°C) compared with control (37.1 ± 2.1°C) (P < 0.01). Conclusions: These results support the growing body of evidence that carpal tunnel syndrome can affect small afferent fibers. Muscle Nerve 56: 814–816, 2017
Clinical, biochemical, molecular, and histological features of 65 Portuguese patients with mitochondrial disorders
Authors: Cruz Simão , Taipa Ricardo , Nogueira Célia , Pereira Cristina , Almeida Lígia S. , Neiva Raquel , Geraldes Tiago , Guimarães António , Melo‐Pires Manuel , Vilarinho Laura
Published: January 2017

Introduction

Mitochondrial disorders display remarkable genetic and phenotypic heterogeneity.

Methods

We performed a retrospective analysis of the clinical, histological, biochemical, and genetic features of 65 patients with molecular diagnoses of mitochondrial disorders.

Results

The most common genetic diagnosis was a single large‐scale mitochondrial DNA (mtDNA) deletion (41.5%), and the most frequent clinical phenotype was chronic progressive external ophthalmoplegia (CPEO). It occurred in 41.5% of all patients, primarily in those with mtDNA deletions. Histological signs of mitochondrial dysfunction were found in 73.8% of patients, and respiratory chain enzyme assay (RCEA) abnormalities were detected in 51.9%.

Conclusions

This study confirms the high relative frequency of single large‐scale deletions among mitochondrial disorders as well as its particular association with CPEO. Muscle histology seems to be particularly useful in older patients and those with mtDNA deletions, whereas RCEA might be more helpful in young children or individuals with mtDNA depletion. Muscle Nerve 56: 868–872, 2017
A hash‐based distributed mapping control scheme in mobile locator‐identifier separation protocol networks
Authors: Gohar Moneeb , Bashir Faisal , Choi Jin‐Ghoo , Koh Seok‐Joo , Ahmad Waleed
Published: January 2017

In the locator‐identifier separation protocol (LISP), the existing mapping control scheme is based on a centralized approach, in which a map server is used as a mobility anchor for mobile hosts. However, such a centralized scheme has some limitations that include traffic overhead at the central map server, service degradation by a single point of failure, and large data transmission delay. In this article, we propose a new hash‐based distributed mapping control scheme of endpoint identifier (EID) and local locator in the LISP‐based mobile networks. In the proposed scheme, each access router in the mobile network has a distributed local map server. For a mobile host, a distributed local map server is designated to manage the associated EID‐local locator mapping by using a hash function. For roaming support, each gateway has a distributed global map server, which maintains visiting EID‐locator register. From the numerical results, we see that the proposed scheme can reduce the amount of control traffic at the map server and total signaling delay compared to the existing mapping control schemes.
Direct evaluation of stress intensity factors for curved cracks using Irwin's integral and XFEM with high‐order enrichment functions
Authors: Wang Yongxiang , Waisman Haim , Harari Isaac
Published: January 2017

This paper presents a comprehensive study on the use of Irwin's crack closure integral for direct evaluation of mixed‐mode stress intensity factors (SIFs) in curved crack problems, within the extended finite element method. The approach employs high‐order enrichment functions derived from the standard Williams asymptotic solution, and SIFs are computed in closed form without any special post‐processing requirements. Linear triangular elements are used to discretize the domain, and the crack curvature within an element is represented explicitly. An improved quadrature scheme using high‐order isoparametric mapping together with a generalized Duffy transformation is proposed to integrate singular fields in tip elements with curved cracks. Furthermore, because the Williams asymptotic solution is derived for straight cracks, an appropriate definition of the angle in the enrichment functions is presented and discussed. This contribution is an important extension of our previous work on straight cracks and illustrates the applicability of the SIF extraction method to curved cracks.

The performance of the method is studied on several circular and parabolic arc crack benchmark examples. With two layers of elements enriched in the vicinity of the crack tip, striking accuracy, even on relatively coarse meshes, is obtained, and the method converges to the reference SIFs for the circular arc crack problem with mesh refinement. Furthermore, while the popular interaction integral (a variant of the J‐integral method) requires special auxiliary fields for curved cracks and also needs cracks to be sufficiently apart from each other in multicracks systems, the proposed approach shows none of those limitations. Copyright © 2017 John Wiley & Sons, Ltd.
Hyperbranched narrow‐bandgap DPP homopolymers synthesized via direct arylation polycondensation
Authors: Wang Kai , Wang Mingfeng
Published: January 2017

Narrow bandgap and hyperbranched polymers (h‐PTDPP) are synthesized by directly arylation polymerization (DAP) of 2‐bromo‐thiophene‐flanked diketopyrrolopyrrole (Br‐TDPP) as the monomer. Their optical properties as well as chemical structures are studied. The detailed optimization of DAP conditions from catalyst, temperature, solvent, ligand to additive not only leads to high molecular weight h‐PTDPP, but also provides some insight to minimize structural defects in DAP when brominated TDPP is involved as a monomer. The increase in the degree of branching results in lower charge‐carrier mobilities in organic field‐effect transistors involving h‐PTDPP‐3 as the semiconducting channel. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1040–1047
Synthesis and characterization of chiral poly(l‐lactide‐b‐hexyl isocyanate) macromonomers with norbornenyl end groups and their homopolymerization through ring opening metathesis polymerization to afford polymer brushes
Authors: Choinopoulos Ioannis , Koinis Spyros , Pitsikalis Marinos
Published: January 2017

We report the synthesis of the novel half‐titanocene alkoxide complex bischloro‐η5‐cyclopentadienyl(bicyclo[2.2.1]‐hept‐5‐en‐2‐oxy) titanium (IV), [CpTiCl2(O‐NBE)]. This complex was employed for the synthesis of chiral poly(l‐lactide‐b‐hexyl isocyanate) diblock copolymer bearing a norbornene end group with sequential addition of monomers. The poly(hexyl isocyanate) block is chiral due to the last l‐lactide unit of the poly(l‐lactide) block. This macromonomer was polymerized towards a chiral polymer brush structure with polynorbornene backbone and chiral poly(l‐lactide‐b‐hexyl isocyanate) side chains using Grubbs first‐generation catalyst. The polymers were characterized using size exclusion chromatography (SEC), nuclear magnetic resonance (NMR), and circular dichroism (CD) spectroscopy and their thermal properties were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1102–1112