bluuebunny/crossref_metadata_2025_split huggingface dataset:
Whale‐watching trips in Peru lead to increases in tourist knowledge, pro‐conservation intentions and tourist concern for the impacts of whale‐watching on humpback whales
Authors: García‐Cegarra Ana M. , Pacheco Aldo S. 
Published: March 2017

Abstract

Since the implementation of the commercial whaling ban in the 1980s, whale‐watching has become the most important economic activity involving whales worldwide.
Whale‐watching is promoted as a platform for education and conservation awareness of marine biodiversity. In Peru, where cetacean species are still in jeopardy, whale‐watching may play an important part in promoting the protection of these species.
This study aimed to determine the degree of whale‐watching tourists' knowledge regarding cetacean ecology and conservation status and to evaluate if whale‐watching tours could serve as platforms for educating the public and raising conservation awareness.
The results of 196 closed‐ended questionnaires and 20 open‐ended interviews conducted before and after whale‐watching tours, during the humpback whale season (winter–spring 2014) in northern Peru, revealed an overall lack of knowledge concerning the presence of species of cetaceans in Peruvian waters and threats to marine biodiversity. However, after the whale‐watching excursion, participants said they would be more willing to change their behaviour with respect to cetacean conservation and marine environment protection.
This study suggests that whale‐watching platforms, when implemented with adequate interpreters, can serve as a source of environmental education and can raise conservation awareness. This is an important conservation strategy to consider in countries, such as Peru, where by‐catch and direct hunting are decimating local cetacean populations.
Amorphous Hole‐Transporting Material based on 2,2′‐Bis‐substituted 1,1′‐Biphenyl Scaffold for Application in Perovskite Solar Cells
Authors: Magomedov Artiom , Sakai Nobuya , Kamarauskas Egidijus , Jokubauskaitė Gabrielė , Franckevičius Marius , Jankauskas Vygintas , Snaith Henry J. , Getautis Vytautas 
Published: March 2017

AbstractPerovskite solar cells are considered a promising technology for solar‐energy conversion, with power conversion efficiencies currently exceeding 20 %. In most of the reported devices, Spiro‐OMeTAD is used for positive‐charge extraction and transport layer. Although a number of alternative hole‐transporting materials with different aromatic or heteroaromatic fragments have already been synthesized, a cheap and well‐performing hole‐transporting material is still in high demand. In this work, a two‐step synthesis of a carbazole‐based hole‐transporting material is presented. Synthesized compounds exhibited amorphous nature, good solubility and thermal stability. The perovskite solar cells employing the newly synthesized material generated a power conversion efficiency of 16.5 % which is slightly lower than that obtained with Spiro‐OMeTAD (17.5 %). The low‐cost synthesis and high performance makes our hole‐transport material promising for applications in perovskite‐based optoelectronic devices.
Three‐Component Asymmetric Mannich Reaction Catalyzed by a Lewis Acid with Rhodium‐Centered Chirality
Authors: Feng Lihe , Dai Xuemei , Meggers Eric , Gong Lei 
Published: March 2017

AbstractA highly efficient direct asymmetric three‐component Mannich reaction of an N‐acylpyrazole, an aldehyde and a primary or secondary amine, was enabled by a rhodium‐based Lewis‐acid catalyst with metal‐centered chirality. Excellent enantioselectivities were achieved for a variety of substrates at a typical catalyst loading of merely 0.5 mol % (23 examples, up to 98 % ee).
Sequence‐Dependent Self‐Assembly of Chiral Polyimides
Authors: Yan Jijun , Kang Chuanqing , Bian Zheng , Jin Rizhe , Ma Xiaoye , Du Zhijun , Yao Haibo , Gao Lianxun 
Published: March 2017

AbstractSequence‐defined chiral polyimides comprising identical asymmetric diamine monomers arranged in different directions along the main chain were designed and prepared. These new sequence‐defined polymers exhibit sequence‐dependent self‐assembly behaviors and responses to ibuprofen enantiomers, as revealed by their chiroptical spectra and gelation properties. For the first time, the self‐assembly of polymers and their interactions with guest molecules have been successfully controlled by means of the directional arrangement of the monomers in their polymer backbones.
Simultaneous determination of piperaquine and its N‐oxidated metabolite in rat plasma using LC‐MS/MS
Authors: Liu Huixiang , Zang Meitong , Yang Aijuan , Ji Jianbo , Xing Jie 
Published: March 2017

AbstractA sensitive and efficient liquid chromatography tandem mass spectrometry method was developed and validated for the simultaneous determination of piperaquine (PQ) and its N‐oxidated metabolite (PQ‐M) in plasma. A simple protein precipitation procedure was used for sample preparation. Adequate chromatographic retention was achieved on a C18 column under gradient elution with acetonitrile and 2 mm aqueous ammonium acetate containing 0.15% formic acid and 0.05% trifluoroacetic acid. A triple‐quadrupole mass spectrometer equipped with an electrospray source was set up in the positive ion mode and multiple reaction monitoring mode. The method was linear in the range of 2.0–400.0 ng/mL for PQ and 1.0–50.0 ng/mL for PQ‐M with suitable accuracy, precision and extraction recovery. The lower limits of detection (LLOD) were established at 0.4 and 0.2 ng/mL for PQ and PQ‐M, respectively, using 40 μL of plasma sample. The matrix effect was negligible under the current conditions. No effect was found for co‐administrated artemisinin drugs or hemolysis on the quantification of PQ and PQ‐M. Stability testing showed that two analytes remained stable under all relevant analytical conditions. The validated method was successfully applied to a pharmacokinetic study performed in rats after a single oral administration of PQ (60 mg/kg).
Inducing Hetero‐aggregation of Different Azo Dyes through Electrostatic Self‐Assembly
Authors: Mariani Giacomo , Kutz Anne , Di Zhenyu , Schweins Ralf , Gröhn Franziska 
Published: March 2017

AbstractCombining chemically different building blocks in supramolecular nanoparticles is a promising key to tailored structures and functionalities. π–π heterostacks of dye molecules form upon electrostatic self‐assembly with a polyelectrolyte, resulting in stable ternary nano‐assemblies in aqueous solution. Core‐shell spheres, cylinders, and flexible cylinders result, which exhibit new shapes different from the binary systems. Particle shapes can be tuned through the dye composition.
Thermally Induced Crystallization of High Quality CH3NH3PbI3 Film with Large Grains for Highly Efficient Perovskite Solar Cells
Authors: Hou Yu , Yang Shuang , Chen Xiao , Li Chunzhong , Zhao Huijun , Yang Hua Gui 
Published: March 2017

AbstractRecently, fully covered and smooth perovskite films could be fabricated by optimized coating methods; however, it is still hard to prepare perovskite films with large grain sizes and high crystallinity. Given the fact that thermal energy can promote crystallization, we combine high‐temperature crystallization with the application of a solvent featuring a high boiling point, in order to produce high quality perovskite films with micrometer‐sized grains. We further investigated the temperature dependence of the thermally induced synthetic strategy, whereby the grains become larger as the temperature is elevated. After solar cell device fabrication, the efficiency of the best cell can attain a high value of 15.53 % with reduced hysteresis behavior.
A Highly Effective Strategy for Encapsulating Potassium Cations in Small Crown Ether Rings on a Dinuclear Palladium Complex
Authors: Lucio‐Martínez Fátima , Bermúdez Brais , Ortigueira Juan M. , Adams Harry , Fernández Alberto , Pereira M. Teresa , Vila José M. 
Published: March 2017

AbstractThe potential of 15‐crown‐5 ethers to link large cations, such as potassium, is limited by the quasi‐parallel arrangement of two oxygen donor moieties upon appropriate orientation of the corresponding ether‐ring‐containing molecules. Substrates bearing the two crown ethers that are capable of achieving such coordination are hitherto unknown. The synthesis and isolation of a tailor‐made dinuclear palladacycle bearing 15‐crown‐5 ether rings on the metallated phenyls offers such a possibility, providing the adequate environment for the formation of the sandwiched [K(metallacycle‐15‐crown‐5)2] moiety. This synthetic strategy also culminates in the isolation of the first palladacycle able to entrap a potassium cation through bonding to two 15‐crown‐5 ether rings in a single molecule.
Enantiopure versus Racemic Naphthalimide End‐Capped Helicenic Non‐fullerene Electron Acceptors: Impact on Organic Photovoltaics Performance
Authors: Josse Pierre , Favereau Ludovic , Shen Chengshuo , Dabos‐Seignon Sylvie , Blanchard Philippe , Cabanetos Clément , Crassous Jeanne 
Published: March 2017

AbstractImpact of the enantiopurity on organic photovoltaics (OPV) performance was investigated through the synthesis of racemic and enantiomerically pure naphthalimide end‐capped helicenes and their application as non‐fullerene molecular electron acceptors in OPV devices. A very strong increase of the device performance was observed by simply switching from the racemic to the enantiopure forms of these π‐helical non‐fullerene acceptors with power conversion efficiencies jumping from 0.4 to about 2.0 % in air‐processed poly(3‐hexylthiophene)‐based devices, thus highlighting the key role of enantiopurity in the photovoltaic properties.
The density matrix theory of triple‐quantum filtered COSY (TQF‐COSY) NMR experiments applied to an AX system of spins S=1: An example of passive coupling in two‐dimensional NMR spectroscopy
Authors: Kempgens Pierre , Pinchuck Andrew L. 
Published: March 2017

AbstractThe 2D Triple‐Quantum Filtered (TQF) COSY NMR spectrum of an AX spin system of spin‐1 has been calculated by numerical density matrix calculations. The basic phase cycle to achieve triple quantum filtration and phase‐modulation of the signal during t1 consists of 12 steps. If nuclei A and X are not coupled, the calculations predict no peaks at all. If nuclei A and X are coupled and the multiplets are not resolved in the conventional 1D spectrum, two diagonal peaks are detected. If nuclei A and X are coupled and the multiplets are resolved in the conventional 1D spectrum, only diagonal and near‐diagonal peaks are detected. One does not observe cross peaks if nuclei A and X are coupled because the coupling is passive. It is believed that the calculations presented here will be needed to calculate the Exclusive Correlation Spectroscopy (E.COSY) of an AX system of spins S=1.
Toward recording 33S NMR spectra of cross‐linked elastomers: Relaxation dynamics perspective
Authors: Marhabaie Sina , Tekely Piotr 
Published: March 2017

AbstractWe discuss from the perspective of relaxation dynamics the feasibility of recording NMR spectra of 33S nuclei bound to cross‐link junctions in cross‐linked elastomers (i.e. vulcanized rubber). Assuming the quadrupolar relaxation mechanism due to fluctuating electric field gradients, the calculations of transverse and longitudinal 33S relaxation times encompassing a large range of correlation times, static magnetic fields, and quadrupolar coupling constants reveal that both relaxation processes will constitute significant bottlenecks in recording the 33S spectra of cross‐linked elastomers inherently endowed with a large distribution of motional modes. In the rubbery state, the observable 33S NMR signal will result from motionally averaged, central transition magnetization of the 33S nuclei in cross‐link junctions involved in large amplitude, high‐frequency motions.
The early adoption of intensity‐modulated radiotherapy and stereotactic body radiation treatment among older Medicare beneficiaries with prostate cancer
Authors: Jacobs Bruce L. , Yabes Jonathan G. , Lopa Samia H. , Heron Dwight E. , Chang Chung‐Chou H. , Schroeck Florian R. , Bekelman Justin E. , Kahn Jeremy M , Nelson Joel B. , Barnato Amber E. 
Published: March 2017

BACKGROUNDSeveral new prostate cancer treatments have emerged since 2000, including 2 radiotherapies with similar efficacy at the time of their introduction: intensity‐modulated radiotherapy (IMRT) and stereotactic body radiation therapy (SBRT). The objectives of this study were to compare their early adoption patterns and identify factors associated with their use.METHODSBy using the Surveillance, Epidemiology, and End Results (SEER)‐Medicare database, patients who received radiation therapy during the 5 years after IMRT introduction (2001‐2005) and the 5 years after SBRT introduction (2007‐2011) were identified. The outcome of interest was the receipt of new radiation therapy (ie, IMRT or SBRT) compared with the existing standard radiation therapies at that time. The authors fit a series of multivariable, hierarchical logistic regression models accounting for patients nested within health service areas to examine the factors associated with the receipt of new radiation therapy.RESULTSDuring 2001 to 2005, 5680 men (21%) received IMRT compared with standard radiation (n = 21,555). Men who received IMRT were older, had higher grade tumors, and lived in more populated areas (P < .05). During 2007 through 2011, 595 men (2%) received SBRT compared with standard radiation (n = 28,255). Men who received ng SBRT were more likely to be white, had lower grade tumors, lived in more populated areas, and were more likely to live in the Northeast (P < .05). Adjusting for cohort demographic and clinical factors, the early adoption rate for IMRT was substantially higher than that for SBRT (44% vs 4%; P < .01).CONCLUSIONSThere is a stark contrast in the adoption rates of IMRT and SBRT at the time of their introduction. Further investigation of the nonclinical factors associated with this difference is warranted. Cancer 2017;123:2945–54. © 2017 American Cancer Society.
Economic evaluation of nivolumab as a second‐line treatment for advanced renal cell carcinoma from US and Chinese perspectives
Authors: Wan Xiao Min , Peng Liu Bao , Ma Jin An , Li Yuan Jian 
Published: March 2017

BACKGROUNDNivolumab is a new standard of care for patients with metastatic renal cell carcinoma (mRCC) and provides an overall survival benefit of 5.40 months in comparison with everolimus. This study evaluated the cost‐effectiveness of nivolumab for the second‐line treatment of mRCC from the perspective of US payers and identified the range of drug costs for which the addition of nivolumab to standard therapy could be considered cost‐effective from a Chinese perspective.METHODSA partitioned survival model was constructed to estimate lifetime costs, life‐years, and quality‐adjusted life‐years (QALYs). Costs were estimated for the US and Chinese health care systems. One‐way and probabilistic sensitivity analyses were performed.RESULTSNivolumab provided an additional 0.29 QALYs at a cost of $151,676/QALY in the United States. The probabilistic sensitivity analysis showed that at a willingness‐to‐pay threshold of $100,000/QALY, at the current cost of nivolumab, the chance of nivolumab being cost‐effective was 3.10%. For China, when nivolumab cost less than $7.90 or $9.70/mg, there was a nearly 90% likelihood that the incremental cost‐effectiveness ratio for nivolumab would be less than $22,785 or $48,838/QALY, respectively.CONCLUSIONSFor the United States, nivolumab is unlikely to be a high‐value treatment for mRCC at the current price, and a price reduction appears to be justified. In China, value‐based prices for nivolumab are $7.90 and $9.70/mg for the country and Beijing City, respectively. This study could and should inform the multilateral drug‐price negotiations in China that may be upcoming for nivolumab. Cancer 2017;123:2634‐41. © 2017 American Cancer Society.
Modeling and simulation of large memristive networks
Authors: Biolek Dalibor , Kolka Zdeněk , Biolková Viera , Biolek Zdeněk , Potrebić Milka , Tošić Dejan 
Published: March 2017

SummaryThe paper deals with the modeling of memristors operating in extremely large memristive networks such as crossbar structures for memory and computational circuits, memristor‐based neural networks or circuits for massively parallel analog computations. Because the non‐convergence and other numerical problems increase with increasing complexity of the simulated circuit, suitable models of the individual memristors need to be choicely developed and optimized. Three different models are considered, each representing a specific trade‐off between speed and accuracy. Benchmark circuits for testing the applications of various complexities are used for the transient analysis in HSPICE. It is shown how the models can be modified to minimize the simulation time and improve the convergence. Copyright © 2017 John Wiley & Sons, Ltd.
A novel no‐equilibrium hyperchaotic multi‐wing system via introducing memristor
Authors: Zhou Ling , Wang Chunhua , Zhou Lili 
Published: March 2017

SummaryIn this paper, a new multi‐wing chaotic attractor is constructed. Based on the proposed multi‐wing system, the paper presents a novel method to generate hyperchaotic multi‐wing attractors. By introducing a flux‐controlled memristor into the proposed multi‐wing system, hyperchaotic multi‐wing attractor is observed in new memristive system. At the same time, the new memristive system has no equilibrium. The phase portraits and Lyapunov exponents are used to analyze the dynamic behaviors of the no‐equilibrium memristive system. Moreover, we analyze the influence on multi‐wing system when adding the memristor in different position. The electronic circuit is realized by using off‐the‐shelf components. Copyright © 2017 John Wiley & Sons, Ltd.
Assessing Early‐Stage CO2 utilization Technologies—Comparing Apples and Oranges?
Authors: Zimmermann Arno W. , Schomäcker Reinhard 
Published: March 2017

AbstractCO2 utilization involves many disciplines—fields as different as apples and oranges. Technology assessment is a common tool for evaluation. This article analyses its current state in CO2 utilization. First, the steps of chemical product development are matched with technology readiness levels (TRLs) for classification. Second, relevant literature is selected, and assessment methods and indicators are examined. The analysis shows that standardization in CO2 utilization technology assessment is low. Current research addresses some but not all assessment fields and tends to use a large range of indicators, making comparison difficult. Overall standard methods are needed as they could facilitate technology comparison and provide a better understanding of trade‐offs. Future assessments should be extended to the definition of a standard set of assessment indicators, the further adoption of social impact assessment for all TRLs, and the inclusion of environmental impact assessment at early stages.
The comet assay in Folsomia candida: A suitable approach to assess genotoxicity in collembolans
Authors: Cardoso Diogo N. , Silva Ana Rita R. , Cruz Andreia , Lourenço Joana , Neves Joana , Malheiro Catarina , Mendo Sónia , Soares Amadeu M.V.M. , Loureiro Susana 
Published: March 2017

Abstract

The present study shows the comet assay technique being successfully applied for the first time to one of the most widely used soil organisms in standardized ecotoxicological tests, Folsomia candida, providing a step forward in assessing the genotoxicity induced by xenobiotics. Because collembolans have a high content of chitin, a new methodology was developed in which the heads of the collembolans were separated from the rest of the body, allowing the hemolymph to leak out. This procedure allows the cells to be released, and after lysis the genetic material is available for the comet assay. Among other key procedures, the use of 30 organisms (20- to 22-d-old adults) per replicate and the correct amount of cells with genetic material (translated as 10 μL of suspension) applied on the agarose gel were determinants for the success of the results obtained. The methodology was validated by exposing F. candida to a representative metallic element (cadmium) and a representative of organophosphates, the insecticide dimethoate, for a shorter time period of 10 d, compared with the 28 d for the International Organization for Standardization 11267 method. Within this method, the relatively low percentage of DNA damage (30%) observed in controls and the significant increase in terms of percentage of DNA damage for almost all the concentrations of dimethoate and Cd (reaching 52% and 56% of damage in the highest concentrations, respectively) confirmed the genotoxic effect of both compounds and validated this technique. The comet assay proved to be a sensitive technique to detect DNA strand breaks in collembolans’ cells. Environ Toxicol Chem 2017;36:2514–2520. © 2017 SETAC
Stable nitrogen and carbon isotopes in sediments and biota from three tropical marine food webs: Application to chemical bioaccumulation assessment
Authors: Zhang Hui , Teng Yun , Doan Tra Thi Thanh , Yat Yun Wei , Chan Sheot Harn , Kelly Barry C. 
Published: March 2017

Abstract

Studies of trophodynamics and contaminant bioaccumulation in tropical marine ecosystems are limited. The present study employed stable isotope and trace contaminant analysis to assess sources of primary productivity, trophic interactions, and chemical bioaccumulation behavior in 2 mangrove food webs and 1 offshore coastal marine food web in Singapore. Samples of sediment, phytoplankton, mangrove leaves, clams, snails, crabs, worms, prawns, and fishes were analyzed for stable carbon and nitrogen isotope values, as well as concentrations of persistent organic pollutants. In the mangrove food webs, consumers exhibited similar δ13C values, probably because of the well-mixed nature of these systems. However, the 2 primary consumers (common nerite and rodong snail) exhibited distinct δ13C values (–21.6‰ vs –17.7‰), indicating different carbon sources. Fish from Singapore Strait exhibited similar δ13C values, indicating common carbon sources in this offshore marine food web. The highest trophic level was found in glass perchlet (trophic level = 3.3) and tilapia (trophic level = 3.4) in the 2 mangrove food webs and grunter (trophic level = 3.7) in the Singapore Strait food web. Concentrations of polychlorinated biphenyl (PCB 153) and p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) concentrations ranged from 0.9 to 84.6 ng/g lipid weight and from &lt;0.2 to 267.4 ng/g lipid weight, respectively. The trophic magnification factors of PCB 153 and p,p′-DDE ranged between 1.63 and 4.62, indicating biomagnification in these tropical marine food webs. The findings provide important information that will aid future chemical bioaccumulation assessment initiatives. Environ Toxicol Chem 2017;36:2521–2532. © 2017 SETAC