bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitromodulation of cytochrome P450 isozymes and pharmacokinetics of caffeine by extracts ofHibiscus sabdariffaLinn calyx
Authors: Showande Johnson Segun , Igbinoba Sharon Iyobor , Kajula Marena , Hokkanen Juho , Tolonen Ari , Adegbolagun Olayemi Modupe , Fakeye Titilayo Oyelola 
Published: April 2019

AbstractBackgroundHibiscus sabdariffabeverage (HSB) is widely consumed as a medicinal herb and sometimes used concomitantly with drugs. This study evaluated thein vitroinhibitory potential of the aqueous extract ofH. sabdariffacalyces (AEHS) on selected cytochrome P450 (CYP) isozymes and the effect of HSB on the pharmacokinetics of caffeinein vivo.MethodsIn vitroinhibitions of eight major CYP isozymes by AEHS were estimated by monitoring CYP-specific model reactions of 10 CYP probe substrates usingN-in-one assay method. Subsequently, an open, randomized, two-period crossover design was used to evaluate the effect of HSB on the pharmacokinetics of single-dose 200 mg caffeine in six healthy human volunteers. Blood samples were obtained at specific times over a 24 h period. Probe drugs and metabolites were analyzed in their respective matrices with ultra-performance liquid chromatography/mass spectrometer/mass spectrometer and reversed-phase high-performance liquid chromatography/ultraviolet detection.ResultsTheH. sabdariffaaqueous extract weakly inhibited the selected CYP isozymesin vitro, with IC50of >100 μgmL-1in the order of CYP1A2 > CYP2C8 > CYP2B6 >> CYP2D6 > CYP2C19 > CYP3A4 > CYP2A6 > CYP2C9. HSB decreased terminal t1/2and Tmaxof caffeine by 13.6% and 13.0%, respectively, and increased Cmaxby 10.3%. Point estimates of primary pharmacokinetic endpoints, Cmax= 1.142 (90% confidence interval (CI) = 0.882, 1.480) and AUC0–∞= 0.992 (90% CI = 0.745, 1.320), were outside the 90% CI of 0.8–1.25 bioequivalence limits.ConclusionThe aqueous extract ofH. sabdariffaweakly inhibited eight CYP isozymesin vitro, but HSB modified the exposure to caffeine in human. Caution should be exercised in administering HSB with caffeine or similar substrates of CYP1A2 until more clinical data are available.
Basic Functions of Fiber Bragg Grating Effects on the Optical Fiber Systems Performance Efficiency
Authors: Amiri IS , Zaki Rashed Ahmed Nabih , Yupapin P 
Published: April 2019

Abstract
The study presents the basic apodization and chirp functions based fiber Bragg grating (FBG) for upgrading optical fiber performance efficiency. Variations of apodization and chirp functions are studied with grating length variations. Optical power after FBG, signal to noise ratio, maximum Q-factor, and output power are measured in the presence of the chirp functions. Gaussian apodization function has outlined good performance than other proposed apodization functions. As well as linear chirp function is better performance than other chirp functions. The optical system performance tested with/without chirp effects with high bit rates.
Transpacific Resonances and Affiliations in Leanne Dunic’sto Love the Coming Endand Ruth Ozeki’sthe Tale for the Time Being
Authors: O’Brien Michelle 
Published: April 2019

AbstractThis article examines methods of tracing affiliations across transpacific critiques through a reading of Leanne Dunic’sTo Love the Coming Endand Ruth Ozeki’sThe Tale for the Time Being. The article proposes that, rather than reproducing a nation-bound framing of the 2011 earthquake off the Pacific coast of Tōhoku that envisions it as a solely Japanese crisis, Dunic’s and Ozeki’s works explore what it would mean to read the earthquake and its aftermath as a transpacific event. It argues that these works facilitate new relations between national cultures and the global, suggesting that, by narrating the earthquake and recovering its transpacific resonances, both works recover and write transcultural links that are obscured in nation-bound narratives of events. By self-reflexively commenting on this process of creative forms of transpacific intimacy, Dunic’s and Ozeki’s works directly address the potential for literary narratives to implicate individuals from disparate nations in a global, historical, narrative of events
Mechanistic role of plant-based bitter principles and bitterness prediction for natural product studies I: Database and methods
Authors: Ntie-Kang Fidele 
Published: April 2019

Abstract
This chapter discusses the rationale behind the bitter sensation elicited by chemical compounds, focusing on natural products. Emphasis has been placed on a brief presentation of BitterDB (the database of bitter compounds), along with available methods for the prediction of bitterness in compounds. The fundamental basis for explaining bitterness has been provided, based on the structural features of human bitter taste receptors and have been used to shed light on the mechanistic role of a few out of the 25 known human taste receptors to provide the foundation for understanding how bitter compounds interact with their receptors. Some case studies of ligand-based prediction models based on 2D fingerprints and 3D pharmacophores, along with machine learning methods have been provided. The chapter closes with an attempt to establish the relationship between bitterness and toxicity.
Transparent Conducting Oxide Films for Various Applications: A Review
Authors: Afre Rakesh A. , Sharma Nallin , Sharon Maheshwar , Sharon Madhuri 
Published: April 2019

Abstract
This review encompasses properties and applications of polycrystalline or amorphous, Transparent Conducting Oxides (TCO) semiconductors. Coexistence of electrical conductivity and optical transparency in TCO depends on the nature, number and atomic arrangements of metal cations in oxides, on the resident morphology and presence of intrinsic or introduced defects. Therefore, TCO semiconductors that are impurity-doped as well as the ternary compounds and multi-component oxides consisting of combinations are discussed. Expanding use of TCO is endangered by scarcity, cost of In, fragility of glass, limited transparency to visible light, instability above >200 °C, non-flexible for application of flexible solar cell; thus driving search for alternatives such as graphene or CNT, that are more stable under acidic, alkaline, oxidizing, reducing and elevated temperature. There are reasons to conclude that there is need to develop large area deposition techniques to produce TCO films with high deposition rate. TCOs are mostly n-type semiconductors, but p-type are also being researched
Immobilization of Lipase on Iron Oxide Organic/Inorganic Hybrid Particles: A Review Article
Authors: Ali Zafar , Li Tian , Khan Muhammad , Ali Nisar , Zhang Qiuyu 
Published: April 2019

Abstract
In last few decades the demand of lipase has been dramatically increase due to its useful use in numbers of biochemical industries. Varieties of natural and synthetic carriers and methodologies have been used to improve lipase activities by the process of immobilization in order to enhance its activities in term of its resistance to high temperature, pH and to increase its reusibity and storage capacity. Due to the expensive nature the recycling of the lipase has been the target of the researchers to decrease its cost in the industrial process. Magnetic iron oxide organic/inorganic hybrid nanoparticles as a support have been mostly used in the lipase immobilization due its large surface area, less toxicity, bio compatibility, easily functionalization, separation avoiding long time consuming process like filtration and centrifuging.
A Brief Review of Structural, Electrical and Electrochemical Properties of Zinc Oxide Nanoparticles
Authors: Parihar Vandana , Raja Mohan , Paulose Rini 
Published: April 2019

Abstract
Nanotechnology allocate with the production and usage of material with nanoscale dimension, nanoparticles are large surface area to volume ratio and thus very specific properties. Zinc oxide (ZnO) nanoparticles had been in current studies due to its large bandwidth and high exciton binding energy and it has prospective applications such as electronic, optical, mechanical, magnetic and chemical properties that are significantly different from those of bulk counterpart. The aims of this review to provide a comprehensive view on structural, synthesis and electrochemical properties of the ZnO nanoparticles, which were synthesized by different methods.
Negative Magnetization in Perovskite RTO3 (R=Rare-Earth, T=Cr/Mn)
Authors: Biswas Sanjay , Pal Sudipta 
Published: April 2019

Abstract
The present review presents a detail discussion of the phenomenon of magnetization reversal (or negativemagnetization) phenomena.Avariety of magnetically ordered systems shows negative magnetization. However, this negative magnetization in these materials does not arise due to diamagnetism. Here we have focused a special group of ceramic oxides namely RTO3 (R=rare-earth, T=Cr/Mn). In these oxides sign of the magnetic moment reverses mainly due to negative exchange coupling among ferromagnetic/canted-antiferromagnetic and paramagnetic sublattices. Finally, the practical utilization of this type of materials is included in this review.
Poly(Hydroxybutyrate) and Norbixin as Biomaterials In Biological Applications
Authors: Sousa R. C. , Almeida F. R. C. , Viana V. G. F. , Carvalho L. F. M. , Vasconcelos D. F. P. 
Published: April 2019

Abstract
This review presents the survey of performance of biomaterials prepared using norbixina and poly(hydroxybutyrate) as biomaterials in biological applications. Biomaterials can replace and/or stimulate biological systems that no longer have their functions, such as the restoration of tissue functions. In the field of biomaterials, norbixin is an antioxidant dicarboxylic carotenoid found in Bixa orellana L. and poly(hydroxybutyrate) (PHB) is a natural polymer that has characteristics of biodegradability and biocompatibility. There is a shortage of studies involving such constituents together as biomembranes in tissue healing with repair of cutaneous wounds or bone regeneration, although both present promising research that suggests its effectiveness as a guide for tissue regeneration.
Microstructure and Properties of Fine Grained Cu-Cr-Zr Alloys after Termo-Mechanical Treatments
Authors: Morozova A. , Mishnev R. , Belyakov A. , Kaibyshev R. 
Published: April 2019

Abstract
Cu-Cr-Zr alloys provide an excellent combination of strength and electric conductivity and are frequently used as engineering materials in various electric/electronic devises. The present review deals with the microstructural design of Cu-Cr-Zr alloys, their alloying concept, thermo-mechanical processing based on technique of severe plastic deformation, physical mechanisms responsible for high strength and electric conductivity. The influences of microstructure and a dispersion of secondary phases on the mechanical properties and electric conductivity are discussed in detail. First, precipitation sequences during aging that leads to depletion of Zr and Cr solutes from Cu solution are critically reviewed in close connection with interaction mechanisms between dislocations and particles. Then, the main structure-property relationships of Cu-Cr-Zr alloys are considered. Finally, the strengthening of Cu-Cr-Zr alloys through severe plastic deformation by means of submicrocrystalline/nanocrystalline structure and increasing dislocation density as well as the effects of post-deformation heat treatment on the mechanical and electric properties are discussed.
Magnetic Sio2-Fe3O4 Nanocomposites as Carriers of Ibuprofen for Controlled Release Applications
Authors: González-Hurtado M. , Marins J. A. , Soares B. Guenther , Briones J. Rieumont , Rodríguez A. Rodríguez , Ortiz-Islas E. 
Published: April 2019

Abstract
In the present paper, we report the preparation and characterization of magnetic silica nanostructured materials that were used as ibuprofen drug molecule carriers. This work was aimed at obtaining drug release systems sensitive to a magnetic field to be directed to target sites. The preparation of the silica nanostructuredmaterials started with the synthesis of magnetite (Fe3O4) nanoparticles that were added subsequently during the hydrolysis and condensation of tetraethyl-orthosilicate (TEOS) to obtain SiO2-Fe3O4 nanocomposites. The ibuprofen molecules were added simultaneously with magnetite nanoparticles. The in vitro ibuprofen release profiles were analyzed, showing a typical controlled release for all materials studied. The nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning microscopy (SEM), thermogravimetric analysis (TGA), N2 adsorption-desorption isotherms; magnetic studies were also performed. The obtained materials showed low superparamagnetic values, and saturation behavior was also observed. It was demonstrated that ibuprofen does not affect the magnetic behavior of magnetite, indicating its possible use in medical applications.
Design and Construction of an Embedded Fuzzy-Optical System to Characterize Metamaterials
Authors: Castañeda-Miranda Alejandro , Castaño Víctor M. 
Published: April 2019

Abstract
A fuzzy logic-based embedded system to characterize materials and metamaterials is presented. Trapezoidal and Gaussian profiles, used as membership functions, allow to classify materials despite variations on light intensity. The results on various materials show the capacity of the system to calculate the refractive index as a complex number, through a fourth order equation. Since all the roots of the equarion, including imaginary ones, the system allow to characterize metamaterials. The embedded character of the systems allows to use it as an external module for most commercial equipments.
Tuning the Structure and the Mechanical Properties of Ultrafine Grain Al–Zn Alloys by Short Time Annealing
Authors: Bobruk E.V. , Sauvage X. , Zakirov A.M. , Enikeev N.A. 
Published: April 2019

Abstract
Solid solution treated Al-Zn alloys with different Zn contents (10 and 30 wt.%) have been nanostructured by severe plastic deformation (SPD) via equal-channel angular pressing method. In-situ transmission electron microscopy observations have been used to follow microstructure evolutions upon annealing. It was shown that SPD leads to the precipitation of Zn particles and that this partial solid solution decomposition was more pronounced in the Al- 30%Zn alloy. Annealing at temperatures in range of 200 to 250 °C led to visible dissolution of Zn particles in both alloys and to formation of extensive grain boundary segregations of Zn. This approach helped to design short term annealing treatments leading to specific ultrafine grain structures that could be achieved by static annealing on bulk samples. Last, the tensile behavior of these materials has been investigated with a special emphasis on the influence of the strain rate on the yield stress and on the elongation to failure. It is shown that in any case the yield stress is mainly controlled by the grain size, while a low volume fraction of Zn phase leads to a relatively modest ductility.
Influence of Severe Plastic Deformation on Microstructure, Strength and Electrical Conductivity of Aged Al–0.4Zr(Wt.%) Alloy
Authors: Orlova T.S. , Mavlyutov A.M. , Latynina T.A. , Ubyivovk E.V. , Murashkin M.Yu. , Schneider R. , Gerthsen D. , Valiev R.Z. 
Published: April 2019

Abstract.
Microstructure evolution of an Al-0.4Zr(wt.%) alloy after isothermal aging (AG) and subsequent high pressure torsion (HPT) and its impact on strength and electrical conductivity has been investigated. Microstructure was characterized by X-ray diffraction, electron backscatter diffraction, transmission electron microscopy (TEM) and electron energy-dispersive X-ray spectroscopy in TEM. The initial Al-0.4Zr(wt.%) alloy obtained by combined casting and rolling presents solid solution of Zr in Al matrix. Aging at 375 °C for 60 h leads to formation of uniformly distributed metastable Al3Zr precipitates with the average diameter of 13 nm, resulting thereby in a decrease of strength sUTS from 128 to 95 MPa and in increase of conductivity from 50.7 to 58.8% IACS at ambient temperature. The subsequent HPT processing leads to grain refinement and partial dissolution of the Al3Zr precipitates that is accompanied by enrichment of solid solution by Zr atoms and by coarsening of the remaining Al3Zr precipitates. The combination of AG and HPT provides the strength and the conductivity at ambient temperature which do not decrease under annealing up to 230 °C. Moreover, additional strengthening accompanied by an increase in conductivity was found for AG-HPT samples after annealing at Tan=230 °C for 1 h, that provides the best combination of the strength of sUTS=142 MPa and the conductivity of 58.3% IACS. Contribution of different possible mechanisms into strength and charge scattering are analyzed on the basis of specific microstructural features. The analysis indicates a suppression of strengthening by the Orowan mechanism in AG and AG-HPT samples. In all the studied states, i.e. initial, after AG, and subsequent HPT, grain boundary strengthening is found to be the main strengthening mechanism.
Adhesion and Mechanical Properties of PDMS-Based Materials Probed with AFM: A Review
Authors: Vlassov S. , Oras S. , Antsov M. , Sosnin I. , Polyakov B. , Shutka A. , Krauchanka M. Yu. , Dorogin L. M. 
Published: April 2019

Abstract
Polydimethylsiloxane (PDMS) is the most widely used silicon-based organic polymer, and is particularly known for its unusual rheological properties. PDMS has found extensive usage in various fields ranging from microfluidics and flexible electronics to cosmetics and food industry. In certain applications, like e.g. dry adhesives or dry transfer of 2D materials, adhesive properties of PDMS play crucial role. In this review we focus on probing the mechanical and adhesive properties of PDMS by means of atomic force microscopy (AFM). Main advantages and limitations of AFM-based measurements in comparison to macroscopic tests are discussed.
Magnetometric Study Of ZnO/CoO Nanocomposites
Authors: Typek J. , Guskos N. , Zolnierkiewicz G. , Sibera D. , Narkiewicz U. 
Published: April 2019

Abstract
ZnO nanoparticles doped with transition metal ions are intensively studied nanomaterials, due to their charges and the spins of electrons that provides new magnetic, optical and transport properties. They find a vast range of applications, ranging from optoelectronics to spintronics. In this context especially important is the room temperature ferromagnetism observed for ZnO doped nanomaterials, although this phenomenon is still a controversial and open topic in material science, mostly due to low reproducibility of results from samples prepared by different techniques. In the first part of this article a short review of papers using magnetometric methods to determine the magnetic characteristics of Co-doped ZnO nanomaterials is presented. Different models introduced to explain room temperature ferromagnetism (carrier mediated ferromagnetism, Co2+-oxygen vacancy pairs, blocked superparamagnetic clusters, Co2+-Zn interstitial pairs, heterogeneous distribution of magnetic ions) are examined and discussed. In the second part, magnetisation study of a new series of nCoO/(1-n)ZnO nanocomposites synthesized by hydrothermal method under higher than previously applied pressure will be described. The obtained experimental results will be analysed and information on magnetic systems responsible for the observed characteristics and the involved magnetic interactions will be deduced.
The Effect of Crystallographic Orientation on the Deformation Mechanisms of Nial Nanofilms under Tension
Authors: Krylova Karina A. , Babicheva Rita I. , Zhou Kun , Bubenchikov Alexey M. , Ekomasov Evgenii G. , Dmitriev Sergey V. 
Published: April 2019

Abstract
Molecular dynamics is applied to study the effect of crystallographic orientation on the plastic deformation mechanisms and mechanical properties of NiAl intermetallic nanofilms subjected to uniaxial tension. It is observed that the deformation mechanisms qualitatively depend on the crystallographic orientation of the nanofilms with respect to the loading direction. Plastic deformation of the nanofilms along [557] crystallographic direction is associated with the edge dislocation sliding in the slip system [001](110). As for the nanofilms stretched along [554] and [111] directions, their deformation occurs first through the dislocation sliding followed by the formation of (112)[11 1] twins. Uniaxial tension of the nanofilms along [559] and [55 11] leads to the nucleation and growth of a martensitic phase followed by their rupture along an interface. The maximum (minimum) strength of 9.9 (7.0) GPa is observed for the nanofilms stretched along the [559] ([554]) crystallographic direction, while the largest (smallest) strain to failure of 27 (15)% is for [559] ([55 11]). Various deformation mechanisms of the nanofilms are explained through computing the Schmid factor for the operational slip system. The results indicate that the crystallographic orientation is among the key parameters controlling the deformation mechanisms and mechanical properties of intermetallic nanofilms.
Effect of Crack Bridging on the Toughening of Ceramic/Graphene Composites
Authors: Bobylev S.V. , Sheinerman A.G. 
Published: April 2019

Abstract
A model is proposed describing the effect of crack bridging on the fracture toughness of ceramic/graphene composites. The dependences of the fracture toughness on the graphene content and the sizes of the graphene platelets are calculated in the exemplary case of yttria stabilized zirconia (YSZ)/graphene composites. The calculations predict that if crack bridging prevails over crack deflection during crack growth, the maximum toughening can be achieved in the case of long graphene platelets provided that the latter do not rupture and adhere well to the matrix. The model shows good correlation with the experimental data at low graphene concentrations.
Stress Concentration and Distribution at Triple Junction Pores of Three-Fold Symmetry in Ceramics
Authors: Vakaeva A.B. , Krasnitckii S.A. , Smirnov A.M. , Grekov M.A. , Gutkin M.Yu. 
Published: April 2019

Abstract
The stress concentration and distribution around a triple-junction pore of three-fold symmetry in a polycrystalline ceramic material is considered. The perturbation method in the theory of plane elasticity is used to solve the problem of a nearly circular pore of three-fold symmetry under remote loading in the first approximation. The solution was specified to the uniaxial tension of convex and concave rounded triangular pores. The stress concentration on the pore surface and the stress distribution in vicinity of the pore along its symmetry axes are studied and discussed in detail. The numerical results, issued from the first-order approximation analytical solution, are compared with those of finite-element calculations.
Effect of Grain Boundaries on the Electron Work Function of Ultrafine Grained Aluminum
Authors: Orlova T.S. , Ankudinov A.V. , Mavlyutov A.M. , Resnina N.N. 
Published: April 2019

Abstract
The electron work function (EWF) of ultrafine grained (UFG) aluminum structured by high pressure torsion (HPT) has been investigated. For the first time, the dependence of the EWF on the specific length of grain boundaries (or the grain size) for UFG Al has been obtained. The change of average grain size was achieved by short term annealing of HPT-processed aluminum at different temperatures from the range 90-400 °C. It has been shown that the state of grain boundaries (GBs) affects the magnitude of the EWF. It has been found that the transformation of GBs due to annealing at 90 °C from a nonequilibrium to more equilibrium state while maintaining the specific length of GBs and their average misorientation is accompanied by a decrease in average GB specific energy by 0.3 J m-2. This transition provides a sharp increase in the EWF of the UFGAl by 0.25 eV.