bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of C4C5 Cycloalkyl‐Fused and C6‐Modified Chromans via ortho‐Quinone Methides
Authors: Tangdenpaisal Kassrin , Chuayboonsong Kanokpish , Sukjarean Patchaya , Katesampao Varisa , Noiphrom Nok , Ruchirawat Somsak , Ploypradith Poonsakdi 
Published: February 2015

AbstractStarting from 3,5‐dimethoxybenzaldehyde, some functionalized 2,3,4‐trisubstituted tricyclic 4,5‐cycloalkyl‐fused and 6‐modified chromans could be prepared via ortho‐quinone methides (o‐QMs)/hetero‐Diels–Alder (HDA) reactions of the appropriate precursors. The bromide at C6 served as a handle for introducing other substituents through palladium‐catalyzed cross‐coupling reactions and other functional‐group transformations. Moderate to high yields (up to 80 %) and diastereoselectivities (up to >99:1) could be obtained under [PtCl4] catalysis. The preferred endo transition state during the cycloaddition reaction played an important role in governing the stereochemical outcomes at C2C3C4. The configurationally fixed E geometry of the bicyclic o‐QMs influenced the cycloaddition reactions to favor the C2C4 cis relationship.
Complexity analysis of spatial distribution of precipitation: an application to Bosnia and Herzegovina
Authors: Mihailović Dragutin T. , Drešković Nusret , Mimić Gordan 
Published: February 2015

AbstractWe have used the Kolmogorov complexity (KC) and three suggested complexity measures to describe the complexity of spatial distribution of precipitation in Bosnia and Herzegovina, for the period 1960–1984. In particular, we have examined the monthly precipitation amount time series from 23 stations and then calculated the KC using the Lempel–Ziv Algorithm (LZA), Kolmogorov complexity spectrum (KCS), Kolmogorov complexity spectrum highest value (KCM) and overall Kolmogorov complexity (OKC) values for each time series. Our results indicate that the difference in complexity of spatial distribution of precipitation may be attributed to influence of Adriatic Sea, relief and Pannonian Basin.
Functional characterization of a melittin analog containing a non‐natural tryptophan analog
Authors: Ridgway Zachary , Picciano Angela L. , Gosavi Pallavi M. , Moroz Yurii S. , Angevine Christopher E. , Chavis Amy E. , Reiner Joseph E. , Korendovych Ivan V. , Caputo Gregory A. 
Published: February 2015

ABSTRACTTryptophan (Trp) is a naturally occurring amino acid, which exhibits fluorescence emission properties that are dependent on the polarity of the local environment around the Trp side chain. However, this sensitivity also complicates interpretation of fluorescence emission data. A non‐natural analogue of tryptophan, β‐(1‐azulenyl)‐L‐alanine, exhibits fluorescence insensitive to local solvent polarity and does not impact the structure or characteristics of several peptides examined. In this study, we investigated the effect of replacing Trp with β‐(1‐azulenyl)‐L‐alanine in the well‐known bee‐venom peptide melittin. This peptide provides a model framework for investigating the impact of replacing Trp with β‐(1‐azulenyl)‐L‐alanine in a functional peptide system that undergoes significant shifts in Trp fluorescence emission upon binding to lipid bilayers. Microbiological methods including assessment of the antimicrobial activity by minimal inhibitory concentration (MIC) assays and bacterial membrane permeability assays indicated little difference between the Trp and the β‐(1‐azulenyl)‐L‐alanine‐substituted versions of melittin. Circular dichroism spectroscopy showed both that peptides adopted the expected α‐helical structures when bound to phospholipid bilayers and electrophysiological analysis indicated that both created membrane disruptions leading to significant conductance increases across model membranes. Both peptides exhibited a marked protection of the respective fluorophores when bound to bilayers indicating a similar membrane‐bound topology. As expected, while fluorescence quenching and CD indicate the peptides are stably bound to lipid vesicles, the peptide containing β‐(1‐azulenyl)‐L‐alanine exhibited no fluorescence emission shift upon binding while the natural Trp exhibited >10 nm shift in emission spectrum barycenter. Taken together, the β‐(1‐azulenyl)‐L‐alanine can serve as a solvent insensitive alternative to Trp that does not have significant impacts on structure or function of membrane interacting peptides. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 104: 384–394, 2015.
Frequency analyser: A new Android application for high precision frequency measurement
Authors: Gómez‐Tejedor José A. , Castro‐Palacio Juan C. , Monsoriu Juan A. 
Published: February 2015

AbstractWe present Frequency Analyser, an AndroidTM application for measuring the fundamental frequency of a sound wave with very high precision in a frequency range between 100 Hz and 11 kHz. The application allows exporting the data of frequency as a function of time to an ASCII file. Several examples of application to Physics and Engineering teaching experiments are presented. © 2015 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:471–476, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21618
Studying the standard's requirements for elastomeric seismic isolators by virtual testing
Authors: Blostotsky Boris , Efraim Elia 
Published: February 2015

ABSTRACTModern international standards to end products include a complex of requirements to parameters, materials, performance, and methods of control and acceptance. Development and implementation of standards in practice requires studying of them by a wide range of experts in areas of development of these products, manufacturing techniques, control and acceptance, as well as in areas of their final application. The new standard EH15129 “Antiseismic devices“ includes requirements to elastomeric isolators which are widely applied in seismic protection systems of bridges and other civil structures. Requirements to isolators are provided as results of tests in regimes closest to operational. In this paper we propose a method for studying the requirements of the standard by virtual testing of seismic isolators virtual models. At these virtual tests the time‐varying actions are reproduced according to the standards requirements (constant, ramp, triangular, and sinusoidal). Virtual models of isolators allow to realize their main properties that affect the test results, such as non‐linear elasticity, scragging, damping, creep, and elastic‐plastic behavior. For realization of the method, a Simulink environment of MatLab is adopted, allowing to reproduce virtual testing in the form closest to the real tests. The set of virtual models for tests has been created and presented in the form of virtual laboratory which includes library of models of isolators, library of loadings and library of measuring tools. An example of virtual standard tests of commercially available seismic elastomeric isolator is presented in the paper. © 2015 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:556–566, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21626
A Unified Sensor Architecture for Isothermal Detection of Double‐Stranded DNA, Oligonucleotides, and Small Molecules
Authors: Brown Carl W. , Lakin Matthew R. , Fabry‐Wood Aurora , Horwitz Eli K. , Baker Nicholas A. , Stefanovic Darko , Graves Steven W. 
Published: February 2015

AbstractPathogen detection is an important problem in many areas of medicine and agriculture, which can involve genomic or transcriptomic signatures or small‐molecule metabolites. We report a unified, DNA‐based sensor architecture capable of isothermal detection of double‐stranded DNA targets, single‐stranded oligonucleotides, and small molecules. Each sensor contains independent target detection and reporter modules, enabling rapid design. We detected gene variants on plasmids by using a straightforward isothermal denaturation protocol. The sensors were highly specific, even with a randomized DNA background. We achieved a limit of detection of ∼15 pM for single‐stranded targets and ∼5 nM for targets on denatured plasmids. By incorporating a blocked aptamer sequence, we also detected small molecules using the same sensor architecture. This work provides a starting point for multiplexed detection of multi‐strain pathogens, and disease states caused by genetic variants (e.g., sickle cell anemia).
In Situ Surface‐Enhanced Raman Spectroscopy Study of Plasmon‐Driven Catalytic Reactions of 4‐Nitrothiophenol under a Controlled Atmosphere
Authors: Kang Leilei , Han Xijiang , Chu Jiayu , Xiong Jie , He Xiong , Wang Hsing‐Lin , Xu Ping 
Published: February 2015

AbstractWe demonstrate the plasmon‐driven catalytic reactions of 4‐nitrothiophenol (4NTP) on a single Ag microsphere by an in situ surface‐enhanced Raman spectroscopy (SERS) technique. The highly SERS‐active hierarchical Ag structures served as an ideal platform to study plasmon‐driven catalytic reactions. This single‐particle surface‐enhanced Raman spectroscopy (SP‐SERS) technique coupled with inbuilt apparatus allow us to study the impact of reaction atmospheres and laser power on the rate of dimerization and reduction of 4NTP. Contrary to that found in previous studies, 4NTP could be transformed into 4‐aminothiophenol under H2O or H2 atmosphere. The broadening and splitting of the ν(CC) band during the reaction results from the frequency shift of the ν(CC) band that arises from different products. Our results suggest that the SP‐SERS technique is ideally suited to study plasmon‐driven catalytic reactions because of the possibility to monitor the reaction under controlled atmospheres in real time.
Voltammetry of Layered Black Phosphorus: Electrochemistry of Multilayer Phosphorene
Authors: Wang Lu , Sofer Zdenek , Pumera Martin 
Published: February 2015

AbstractThe front cover artwork is provided by Pumera’s group at Nanyang Technological University, Singapore and Sofer’s group at UCT, Prague. The image shows the structure of black phosphorus on a backdrop of White Sands National Monument, New Mexico, USA. Find out what this unique design represents by reading the Communication at 10.1002/celc.201402363.
Intramolecular Long‐Distance Nucleophilic Reactions as a Rapid Fluorogenic Switch Applicable to the Detection of Enzymatic Activity
Authors: Baba Reisuke , Hori Yuichiro , Kikuchi Kazuya 
Published: February 2015

AbstractLong‐distance intramolecular nucleophilic reactions are promising strategies for the design of fluorogenic probes to detect enzymatic activity involved in lysine modifications. However, such reactions have been challenging and hence have not been established. In this study, we have prepared fluorogenic peptides that induce intramolecular reactions between lysine nucleophiles and electrophiles in distal positions. These peptides contain a lysine and fluorescence‐quenched fluorophore with a carbonate ester, which triggers nucleophilic transesterification resulting in fluorogenic response. Transesterification occurred under mild aqueous conditions despite the presence of a long nine‐amino‐acid spacer between the lysine and fluorophore. In addition, one of the peptides showed the fastest reaction kinetics with a half‐life time of 3.7 min. Furthermore, the incorporation of this fluorogenic switch into the probes allowed rapid fluorogenic detection of histone deacetylase (HDAC) activity. These results indicate that the transesterification reaction has great potential for use as a general fluorogenic switch to monitor the activity of lysine‐targeting enzymes.
Cystatin C–based CKD‐EPI Equations and N‐Terminal Pro‐B‐Type Natriuretic Peptide for Predicting Outcomes in Acutely Decompensated Heart Failure
Authors: Flores‐Blanco Pedro J. , Manzano‐Fernández Sergio , Pérez‐Calvo Juan I. , Pastor‐Pérez Francisco J. , Ruiz‐Ruiz Francisco J. , Carrasco‐Sánchez Francisco J. , Morales‐Rull José L. , Pascual‐Figal Domingo , Galisteo‐Almeda Luis , Januzzi James L. 
Published: February 2015

ABSTRACTBackgroundIn patients with acute decompensated heart failure (ADHF), both natriuretic peptides and renal impairment predict adverse outcomes. Our aim was to evaluate the complementary prognosis role of N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) and the newly developed Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) equations based on cystatin C (CysC) for glomerular filtration rate (GFR) estimation in ADHF patients.HypothesisRenal impairment assessed by CysC‐based CKD‐EPI equations and natriuretic peptides have complementary prognostic value in ADHF patients.MethodsThe study included 613 consecutive patients presenting with ADHF. At admission, plasma levels of NT‐proBNP and CysC were determined. The GFR was estimated using CysC‐based CKD‐EPI equations. The primary endpoint was death from any cause and heart failure readmission.ResultsDuring the median follow‐up of 365 days (interquartile range, 227–441 days), 323 patients (0.65 %patient‐year) died or were readmitted for heart failure. After multivariate adjustment, estimated GFR <60 mL/min/1.73 m2 and NT‐proBNP >3251 pg/mL were independent predictors of adverse outcomes (P < 0.01). The combination of GFR <60 mL/min/1.73 m2 and NT‐proBNP >3251 pg/mL was associated with the highest risk of adverse outcomes. Furthermore, reclassification analyses demonstrated that use of both NT‐proBNP and CysC‐based CKD‐EPI equations resulted in improving the accuracy for adverse outcomes prediction.ConclusionsIn patients with ADHF, the combination of NT‐proBNP with estimated GFR using CysC‐based CKD‐EPI equations better predicts outcomes than either parameter alone and adds valuable complementary prognosis information to other established risk factors.
Electric‐Field‐Induced Viscosity Change of a Nematic Liquid Crystal with Gold Nanoparticles
Authors: Kaneko Kosuke , Ujihara Yoshihiro , Oto Kodai , Hashishin Takeshi , Hanasaki Tomonori 
Published: February 2015

AbstractThe electro‐rheological (ER) effect of a composite material consisting of a nematic liquid crystal (LC) and gold nanoparticles covered with mesogenic groups is discussed. The gold nanoparticles are covered by alkyl chains and liquid‐crystalline compounds. The influences of the alkyl‐chain length and the coverage by the alkyl chain and the mesogenic group on the miscibility of the nanoparticles with the LC are investigated by polarizing optical microscopy (POM). The presence of the gold nanoparticles in the nematic LC (5CB) leads to an enhanced ER response compared to that observed for 5CB. The prominent ER effect observed in this study is supported by the two mechanisms proposed, that is, the homogeneous and heterogeneous mechanisms. This study demonstrates the potential of a hybrid system consisting of an LC and gold nanoparticles to improve the ER effect.
Cyclodextrin 3‐Functionalized with 8‐Hydroxyquinoline as an Antioxidant Inhibitor of Metal‐Induced Amyloid Aggregation
Authors: Oliveri Valentina , Bellia Francesco , Vecchio Gzaziella 
Published: February 2015

AbstractCyclodextrins are used increasingly in pharmacotherapy. Experimental and clinical data suggest that cyclodextrins can be used not only as excipients for marketed drugs, but also as active pharmaceutical ingredients to treat neurological diseases including Niemann–Pick type C disease. Disruption of metal and cholesterol homeostasis, protein misfolding, and aggregation are recognized among the major pathological features in triggering neurodegenerative disorders, and therefore it is becoming more and more evident that the next generation of therapies should have multiple functions to combat the multifactorial nature of diseases. A novel class of compounds obtained by conjugating 8‐hydroxyquinoline with cyclodextrin has been proposed to combine antioxidant activity, chelating, antiaggregant, and inclusion ability into one compound designed for metal‐associated neurodegenerative diseases. Herein, the synthesis and characterization of the new compound 3A‐deoxy‐3A‐[(8‐hydroxyquinolyl)‐2‐methylamino]‐2A(S),3A(R)‐β‐cyclodextrin is reported. Moreover, the interaction of copper–Aβ and zinc–Aβ amyloid with this class of cyclodextrin conjugates was investigated for the first time. New information about the effects of different modified chelating cyclodextrins may be important for further development of drugs against neurodegenerative disorders.
Biomimetic Fenton‐Catalyzed Lignin Depolymerization to High‐Value Aromatics and Dicarboxylic Acids
Authors: Zeng Jijiao , Yoo Chang Geun , Wang Fei , Pan Xuejun , Vermerris Wilfred , Tong Zhaohui 
Published: February 2015

AbstractBy mimicking natural lignin degradation systems, the Fenton catalyst (Fe3+, H2O2) can effectively facilitate lignin depolymerization in supercritical ethanol (7 MPa, 250 °C) to give organic oils that consist of mono‐ and oligomeric aromatics, phenols, dicarboxylic acids, and their derivatives in yields up to (66.0±8.5) %. The thermal properties, functional groups, and surface chemistry of lignin before and after Fenton treatment were examined by thermogravimetric analysis, pyrolysis–gas chromatography–mass spectrometry, 31P NMR spectroscopy, and X‐ray photoelectron spectroscopy. The results suggest that the Fenton catalyst facilitates lignin depolymerization through cleavage of β‐ether bonds between lignin residues. The formation of a lignin–iron chelating complex effectively depresses lignin recondensation; thus minimizing charcoal formation and enhancing the yield of liquid products.
Highly Efficient Hydrogen Storage System Based on Ammonium Bicarbonate/Formate Redox Equilibrium over Palladium Nanocatalysts
Authors: Su Ji , Yang Lisha , Lu Mi , Lin Hongfei 
Published: February 2015

AbstractA highly efficient, reversible hydrogen storage–evolution process has been developed based on the ammonium bicarbonate/formate redox equilibrium over the same carbon‐supported palladium nanocatalyst. This heterogeneously catalyzed hydrogen storage system is comparable to the counterpart homogeneous systems and has shown fast reaction kinetics of both the hydrogenation of ammonium bicarbonate and the dehydrogenation of ammonium formate under mild operating conditions. By adjusting temperature and pressure, the extent of hydrogen storage and evolution can be well controlled in the same catalytic system. Moreover, the hydrogen storage system based on aqueous‐phase ammonium formate is advantageous owing to its high volumetric energy density.
Spatially variable coevolution between a haemosporidian parasite and the MHC of a widely distributed passerine
Authors: Jones Matthew R. , Cheviron Zachary A. , Carling Matthew D. 
Published: February 2015

AbstractThe environment shapes host–parasite interactions, but how environmental variation affects the diversity and composition of parasite‐defense genes of hosts is unresolved. In vertebrates, the highly variable major histocompatibility complex (MHC) gene family plays an essential role in the adaptive immune system by recognizing pathogen infection and initiating the cellular immune response. Investigating MHC‐parasite associations across heterogeneous landscapes may elucidate the role of spatially fluctuating selection in the maintenance of high levels of genetic variation at the MHC. We studied patterns of association between an avian haemosporidian blood parasite and the MHC of rufous‐collared sparrows (Zonotrichia capensis) that inhabit environments with widely varying haemosporidian infection prevalence in the Peruvian Andes. MHC diversity peaked in populations with high infection prevalence, although intra‐individual MHC diversity was not associated with infection status. MHC nucleotide and protein sequences associated with infection absence tended to be rare, consistent with negative frequency‐dependent selection. We found an MHC variant associated with a ~26% decrease in infection probability at middle elevations (1501–3100 m) where prevalence was highest. Several other variants were associated with a significant increase in infection probability in low haemosporidian prevalence environments, which can be interpreted as susceptibility or quantitative resistance. Our study highlights important challenges in understanding MHC evolution in natural systems, but may point to a role of negative frequency‐dependent selection and fluctuating spatial selection in the evolution of Z. capensis MHC.
Development of novel composite antioxidant multiple lipid particles from combination of W/O/W multiple emulsions and solid lipid nanoparticles
Authors: Zhao Guodong , Hu Caibiao , Sun Rui , Ni Shilei , Li Qiwei , Xia Qiang 
Published: February 2015

A novel drug delivery system, multiple solid particles (MLPs), combining the advantages of water‐in‐oil‐in‐water (W/O/W) multiple emulsions and solid lipid nanoparticles (SLN) was proposed. The MLPs were produced by simply adding the solid lipid in liquid lipid of W/O/W multiple emulsions and removing the outer aqueous phase of W/O/W multiple emulsions. MLPs could form typical W/O/W multiple emulsion microstructure by self‐emulsifying after dispersing in water. MLPs were used to encapsulate both coenzyme Q10 and tea polyphenols (CT‐MLPs), and encapsulation efficiency measurement revealed that both coenzyme Q10 and tea polyphenols had high encapsulation efficiency (98.14% and 99.36%, respectively). The effect of the factors on viscosity, stability, and solubility of CT‐MLPs were investigated, and the results showed that increasing the concentration of solid lipid glycerin monostearate or hydrophilic emulsifier polyglyceryl‐10 laurate, or decreasing the concentration of the inner aqueous phase could increase the viscosity of CT‐MLPs. Consequently, the stability of CT‐MLPs was improved by increasing the viscosity of the oil phase. Moreover, addition of glycerin monostearate also increased the water solubility of CT‐MLPs. During a 60‐day stability study, CT‐MLPs showed terrific stability and high retention ratio (above 83.82%) at various conditions.Practical applications: MLPs could act as a drug delivery system to encapsulate both lipophilic active compounds and hydrophilic active compounds, since the active compounds in MLPs had high encapsulation efficiency. MLPs also improved the photostability and storage stability of coenzyme Q10 and tea polyphenols. Furthermore, the production procedure of MLPs is a two‐step stirring method, which is widespread and easy to handle. And the lipids for producing MLPs are physiological lipids, the choice of emulsifiers depends on the administration route. With regard to industrial production aspects, MLPs have the chance to be exploited as drug delivery system in commercial products. Hence, MLPs could be applicable delivery systems for food, cosmetic, and pharmaceutical applications.CT‐MLPs were prepared by a two‐step method and exhibited solidity at room temperature. CT‐MLPs could form typical W/O/W multiple emulsion microstructure by self‐emulsifying after dispersing in water.