bluuebunny/crossref_metadata_2025 huggingface dataset:
Vergussknotenlösungen im Ingenieurholzbau
Authors: Becker Wieland , Schober Kay‐Uwe , Weber Jan
Published: January 2016

Stab‐ und plattenförmige Holzbauelemente werden in Anschlüssen durch stiftförmige Verbindungsmittel, meist in Kombination mit Stahlblechen oder individuell gefertigten Stahlformteilen, miteinander verbunden. Die zunehmend anspruchsvolle Formensprache der Architektur aus digitalen Entwurfsprozessen (Parametric Design) sowie neue Herausforderungen des Holzbaus (mehrgeschossige Bauweise, große Spannweiten) erfordern dabei neue Fügetechniken, welche die bekannten Nachteile konventioneller Holzverbindungen beseitigen. Als Lösungsansatz wird in der vorgestellten Arbeit auf die Vergusstechnologie analog zum Stahlbetonbau zurückgegriffen, wo Bauteile mittels einer Kombination aus Anschlussbewehrung und nachträglich eingebrachtem Vergussmaterial kraft‐ und formschlüssig miteinander verbunden werden. Für die hier vorgestellten Vergussknotenlösungen im Ingenieurholzbau werden Anschlüsse zunächst mit bauaufsichtlich zugelassenen Klebstoffen oder Schrauben werkseitig hergestellt. Auf der Baustelle werden diese dann mechanisch durch Stäbe, Schlaufen oder Stanzformteile gekoppelt und nachträglich vergossen. Dabei kommt ein Polymerbeton als Vergussmaterial zum Einsatz, der eine hohe Druckfestigkeit sowie einen hohen Adhäsionsverbund sowohl zum Holz als auch zum Stahl aufweist. Forschungsziel war die Entwicklung von druck‐, zug‐ und biegebeanspruchten Verbindungen, welche auch bei komplexen Geometrien einen wesentlich vereinfachten Montage‐ und Bauablauf ermöglichen. Erste Forschungsergebnisse und mögliche Praxisanwendungen werden nachfolgend vorgestellt.

Grouting joints in timber engineering

Rod‐ and board‐shaped timber members are connected to‐gether by mechanical fasteners, often together with steel plates or individual formed steel parts. New sophisticated architectural concepts, complex structures due to digital design processes (parametric design) and new challenges in timber engineering (multi‐storey buildings, large scale structures) demand new connecting systems that overcome the well‐known disadvantages of conventional timber joints.

The presented work is based on the grouting technology used in reinforced concrete structures, where structural parts are force‐ and form‐fit connected by a combination of starter bars and a backfitting grouting material. For timber structures, the presented grouting joints follow this technology, where the joints are prefabricated and assembled first by technical approved adhesives or screws. Afterwards on site they are coupled with rods, straps or stamped parts and additional grouted. As grouting material a polymer concrete is used with high compression strength and high adhesive bond to timber as well as to steel. Research objective was the development of joints under compression, tension and bending loads that allow a simplified construction and installation process, even for complex geometries. This paper presents first research results and possible applications offered by this technology.
Eliciting Subjective Probabilities through Pair‐wise Comparisons
Authors: Por Han‐Hui , Budescu David V.
Published: January 2016

We propose and test a novel approach for eliciting subjective joint probabilities. In the proposed approach, judges compare pairs of possible outcomes and identify which of the two is more likely and by how much. These pair‐wise comparative judgments create a matrix of ratio judgments from which the target probabilities are extracted using the rows' (or columns') geometric means. In Study 1, subjects provided direct assessments of the likelihood of joint events (e.g., sunny days and stock market gains) and also made pair‐wise comparisons of the same joint events. Subjects in Study 2 learnt the distribution of hypothetical events pairs and provided direct and ratio estimates. In both studies, the ratio estimates were significantly more accurate than the direct estimates. The results suggest that it is possible to elicit probabilistic estimates without explictly asking for probabilities and that the pair‐wise approach is a candidate for complementing or replacing traditional elicitation approaches. Copyright © 2016 John Wiley & Sons, Ltd.
Eco‐friendly synthesis of gelatin‐capped bimetallic Au–Ag nanoparticles for chemiluminescence detection of anticancer raloxifene hydrochloride
Authors: Alarfaj Nawal A. , El‐Tohamy Maha F.
Published: January 2016

This study described the utility of green analytical chemistry in the synthesis of gelatin‐capped silver, gold and bimetallic gold–silver nanoparticles (NPs). The preparation of nanoparticles was based on the reaction of silver nitrate or chlorauric acid with a 1.0 wt% aqueous gelatin solution at 50°C. The gelatin‐capped silver, gold and bimetallic NPs were characterized using transmission electron microscopy, UV–vis, X‐ray diffraction and Fourier transform infrared spectroscopy, and were used to enhance a sensitive sequential injection chemiluminescence luminol–potassium ferricyanide system for determination of the anticancer drug raloxifene hydrochloride. The developed method is eco‐friendly and sensitive for chemiluminescence detection of the selected drug in its bulk powder, pharmaceutical injections and biosamples. After optimizing the conditions, a linear relationship in the range of 1.0 × 10–9 to 1.0 × 10–1 mol/L was obtained with a limit of detection of 5.0 × 10–10 mol/L and a limit of quantification of 1.0 × 10‐9 mol/L. Statistical treatment and method validation were performed based on ICH guidelines. Copyright © 2016 John Wiley & Sons, Ltd.
α‐Lipoic acid inhibits sevoflurane‐induced neuronal apoptosis through PI3K/Akt signalling pathway
Authors: Ma Rong , Wang Xiang , Peng Peipei , Xiong Jingwei , Dong Hongquan , Wang Lixia , Ding Zhengnian
Published: January 2016

Sevoflurane is a widely used anaesthetic agent, including in anaesthesia of children and infants. Recent studies indicated that the general anaesthesia might cause the cell apoptosis in the brain. This issue raises the concerns about the neuronal toxicity induced by the application of anaesthetic agents, especially in the infants and young children. In this study, we used Morris water maze, western blotting and immunohistochemistry to elucidate the role of α‐lipoic acid in the inhibition of neuronal apoptosis. We found that sevoflurane led to the long‐term cognitive impairment in the young rats. This adverse effect may be caused by the neuronal death in the hippocampal region, mediated through PI3K/Akt signalling pathway. We also showed that α‐lipoic acid offset the effect of sevoflurane on the neuronal apoptosis and cognitive dysfunction. This study elucidated the potential clinical role of α‐lipoic acid, providing a promising way in the prevention and treatment of long‐term cognitive impairment induced by sevoflurane general anesthesia. Copyright © 2016 John Wiley & Sons, Ltd.
Sulfonated Porous Aromatic Frameworks as Solid Acid Catalysts
Authors: Goesten Maarten G. , Szécsényi Àgnes , de Lange Martijn F. , Bavykina Anastasiya V. , Gupta Karthick B. Sai Sankar , Kapteijn Freek , Gascon Jorge
Published: January 2016

The synthesis, characterization, sulfonation, and catalytic performance of two new porous aromatic frameworks are presented. The polymers, which were obtained by the Suzuki–Miyaura cross‐coupling of the commercially available precursors 1,3,5‐tris(4‐bromophenyl)benzene or tris(4‐bromophenyl)amine and benzene‐1 4‐diboronic acid, only contain aromatic sp2 C−C and C−N bonds, display excellent thermal and chemical stability, and allow for post‐synthetic functionalization under very harsh reaction conditions. Upon post‐synthetic treatment at 160 °C in 98 wt % sulfuric acid, approximately 65 % of the benzene rings in the polymers were sulfonated. The materials were characterized by solid‐state NMR spectroscopy, X‐ray photoelectron spectroscopy, FTIR spectroscopy, and textural analysis. The sulfonated materials display an excellent catalytic performance in the acid‐catalyzed esterification of n‐butanol and acetic acid and have a similar or even superior performance to that of state‐of‐the‐art Amberlyst‐15 over multiple catalytic cycles.
Enolate Stabilization by Anion–π Interactions: Deuterium Exchange in Malonate Dilactones on π‐Acidic Surfaces
Authors: Miros François N. , Zhao Yingjie , Sargsyan Gevorg , Pupier Marion , Besnard Céline , Beuchat César , Mareda Jiri , Sakai Naomi , Matile Stefan
Published: January 2016

Invited for the cover of this issue is the group of Stefan Matile at the University of Geneva. The cover image depicts the crystal structure of a malonate dilactone placed on a chiral π‐acidic surface to measure enolate–π interactions during deuterium exchange. Read the full text of the article at 10.1002/chem.201504008.
Visible‐Light‐Mediated Photocatalytic Difunctionalization of Olefins by Radical Acylarylation and Tandem Acylation/Semipinacol Rearrangement
Authors: Bergonzini Giulia , Cassani Carlo , Lorimer‐Olsson Haldor , Hörberg Johanna , Wallentin Carl‐Johan
Published: January 2016

A novel method for the mild photoredox‐mediated tandem radical acylarylation and tandem acylation/semipinacol rearrangement has been developed. The synthesis of highly functionalized ketones bearing all‐carbon α‐ or β‐quaternary centers has been achieved using easily available symmetric aromatic carboxylic anhydrides as the acyl radical source. The method allows for a straightforward introduction of the keto functionality and concomitant construction of molecular complexity in a single operation.
Corrosion inhibition of copper in sodium chloride solution using polyetherimide/graphene composites
Authors: Alhumade Hesham , Abdala Ahmed , Yu Aiping , Elkamel Ali , Simon Leonardo
Published: January 2016

In this study, polyetherimide‐graphene composites (PEI/G) were prepared and investigated as corrosion inhibition coatings on copper substrates. Various loadings of graphene were incorporated in the polyetherimide matrix using an in situ polymerization approach, and the composite coatings were cured by thermal imidization. The effect of graphene loading on corrosion inhibition and the long‐term performance of the PEI/G coatings were investigated. The dispersion of graphene in the polymer matrix was examined using SEM and TEM. The study demonstrated that PEI/G nanocomposites provide advanced corrosion inhibition of copper. This conclusion was supported by the results of various electrochemical techniques such as Tafel polarization and electrochemical impedance spectroscopy (EIS). In addition to corrosion protection, the long‐term performance of the coatings was confirmed by testing the adhesion of PEI/G composites to copper substrates before conducting the electrochemical tests and after 15 days of exposure to the corrosive medium.
Kinesin‐2 and Apc function at dendrite branch points to resolve microtubule collisions
Authors: Weiner Alexis T. , Lanz Michael C. , Goetschius Daniel J. , Hancock William O. , Rolls Melissa M.
Published: January 2016

In Drosophila neurons, kinesin‐2, EB1 and Apc are required to maintain minus‐end‐out dendrite microtubule polarity, and we previously proposed they steer microtubules at branch points. Motor‐mediated steering of microtubule plus ends could be accomplished in two ways: 1) by linking a growing microtubule tip to the side of an adjacent microtubule as it navigates the branch point (bundling), or 2) by directing a growing microtubule after a collision with a stable microtubule (collision resolution). Using live imaging to distinguish between these two mechanisms, we found that reduction of kinesin‐2 did not alter the number of microtubules that grew along the edge of the branch points where stable microtubules are found. However, reduction of kinesin‐2 or Apc did affect the number of microtubules that slowed down or depolymerized as they encountered the side of the branch opposite to the entry point. These results are consistent with kinesin‐2 functioning with Apc to resolve collisions. However, they do not pinpoint stable microtubules as the collision partner as stable microtubules are typically very close to the membrane. To determine whether growing microtubules were steered along stable ones after a collision, we analyzed the behavior of growing microtubules at dendrite crossroads where stable microtubules run through the middle of the branch point. In control neurons, microtubules turned in the middle of the crossroads. However, when kinesin‐2 was reduced some microtubules grew straight through the branch point and failed to turn. We propose that kinesin‐2 functions to steer growing microtubules along stable ones following collisions. © 2016 Wiley Periodicals, Inc.
Cytoskeletal social networking in the growth cone: How +TIPs mediate microtubule‐actin cross‐linking to drive axon outgrowth and guidance
Authors: Cammarata Garrett M. , Bearce Elizabeth A. , Lowery Laura Anne
Published: January 2016

The growth cone is a unique structure capable of guiding axons to their proper destinations. Within the growth cone, extracellular guidance cues are interpreted and then transduced into physical changes in the actin filament (F‐actin) and microtubule cytoskeletons, providing direction and movement. While both cytoskeletal networks individually possess important growth cone‐specific functions, recent data over the past several years point towards a more cooperative role between the two systems. Facilitating this interaction between F‐actin and microtubules, microtubule plus‐end tracking proteins (+TIPs) have been shown to link the two cytoskeletons together. Evidence suggests that many +TIPs can couple microtubules to F‐actin dynamics, supporting both microtubule advance and retraction in the growth cone periphery. In addition, growing in vitro and in vivo data support a secondary role for +TIPs in which they may participate as F‐actin nucleators, thus directly influencing F‐actin dynamics and organization. This review focuses on how +TIPs may link F‐actin and microtubules together in the growth cone, and how these interactions may influence axon guidance. © 2016 Wiley Periodicals, Inc.
Further Investigation of a Nickel‐Based Homogeneous Water Oxidation Catalyst with Two cis Labile Sites
Authors: Luo Gang‐Yi , Huang Hai‐Hua , Wang Jia‐Wei , Lu Tong‐Bu
Published: January 2016

The reaction of N,N′‐dimethyl‐N,N′‐bis(pyridin‐2‐ylmethyl)‐1,2‐diaminoethane ligand (L) with Ni(ClO4)2⋅6 H2O generated a complex of [NiL(H2O)2](ClO4)2 (1) with two cis labile sites occupied by two coordinated H2O molecules, which can homogeneously electrocatalyze water oxidation in pH 6.5 acetate (OAc−) buffer at room temperature. The catalytic mechanism was studied by electrochemical experiments and density functional theory calculations to elucidate the following steps: (a) one of two water molecules in 1 is exchanged by OAc− to generate [NiL(H2O)(OAc)]+ when dissolved in OAc− buffer, (b) NiII is directly oxidized to NiIV and OAc− is replaced with OH− to form [NiIVL(OH)2]2+, and (c) a peroxide intermediate is formed through the intramolecular O−O coupling in the presence of OAc−, which undergoes further oxidation to release O2.
Newly isolated yeasts from Tunisian microhabitats: Lipid accumulation and fatty acid composition
Authors: Arous Fatma , Azabou Samia , Triantaphyllidou Irene‐Eva , Aggelis George , Jaouani Atef , Nasri Moncef , Mechichi Tahar
Published: January 2016

Newly isolated yeasts from different Tunisian microhabitats, such as soil, milk, olive brine, vinegar, and from olive mill wastewater‐contaminated biotopes were extensively studied for their biochemical arsenal and morphological features, i.e. cell, ascospore, and lipid body morphology. All strains were classified into the Ascomycota phylum. However, they showed great functional diversity, including different morphological and biochemical features, lipid production ability, and fatty acid profiles. Accordingly, the strains were placed in three different groups: Group I, which includes Candida species; Group II (Pichia and related); and Group III (Kluyveromyces marxianus strain CC1). Group I and II were characterized by a high percentage of oleic acid (41.6–65.3% of total lipids) while in Group III, linoleic acid was the major fatty acid (37.2%). Members of Group I and II were further grouped into subgroups according to their fatty acid composition. Among the newly isolated strains, Pichia etchellsii BM1 was able to accumulate around 25% wt/wt lipid per dry cell mass and thus characterized as oleaginous. Some other strains, such as Candida metapsilosis strain EL2, C. parapsilosis strain LV2, C. pararugosa strain BM24, and K. marxianus strain CC1, which are able to produce extracellular lipases, may be of interest for specific environmental applications and/or for the production of novel lipases.
Absolute geostrophic velocity inverted from World Ocean Atlas 2013 (WOAV13) with the P‐vector method
Authors: Chu Peter C. , Fan C. W.
Published: January 2016

The World Ocean Atlas‐2013 (WOAV13) dataset comprises 3D global gridded climatological fields of absolute geostrophic velocity inverted from WOA13 temperature and salinity fields using the P‐vector method. It provides a climatological velocity field that is dynamically compatible to the WOA13 (T, S) fields. The WOAV13 has the same spatial resolution and temporal variation (annual, monthly, seasonal) as WOA13 (T, S) fields, but does not cover the equatorial zone (5°S–5°N) due to the geostrophic balance being the theoretical basis for the P‐vector inverse method.
Watershed structural influences on the distributions of stream network water and solute travel times under baseflow conditions
Authors: Bergstrom Anna , McGlynn Brian , Mallard John , Covino Tim
Published: January 2016

Watershed structure influences the timing, magnitude, and spatial location of water and solute entry to stream networks. In turn, stream reach transport velocities and stream network geometry (travel distances) further influence the timing of export from watersheds. Here, we examine how watershed and stream network organization can affect travel times of water from delivery to the stream network to arrival at the watershed outlet. We analysed watershed structure and network geometry and quantified the relationship between stream discharge and solute velocity across six study watersheds (11.4 to 62.8 km2) located in the Sawtooth Mountains of central Idaho, USA. Based on these analyses, we developed stream network travel time functions for each watershed. We found that watershed structure, stream network geometry, and the variable magnitude of inputs across the network can have a pronounced affect on water travel distances and velocities within a stream network. Accordingly, a sample taken at the watershed outlet is composed of water and solutes sourced from across the watershed that experienced a range of travel times in the stream network. We suggest that understanding and quantifying stream network travel time distributions are valuable for deconvolving signals observed at watershed outlets into their spatial and temporal sources, and separating terrestrial and in‐channel hydrological, biogeochemical, and ecological influences on in‐stream observations. Copyright © 2016 John Wiley & Sons, Ltd.
Optimal Portfolio Choice Under Decision‐Based Model Combinations
Authors: Pettenuzzo Davide , Ravazzolo Francesco
Published: January 2016

We propose a density combination approach featuring combination weights that depend on the past forecast performance of the individual models entering the combination through a utility‐based objective function. We apply this model combination scheme to forecast stock returns, both at the aggregate level and by industry, and investigate its forecasting performance relative to a host of existing combination methods, both within the class of linear and time‐varying coefficients, stochastic volatility models. Overall, we find that our combination scheme produces markedly more accurate predictions than the existing alternatives, both in terms of statistical and economic measures of out‐of‐sample predictability. Copyright © 2016 John Wiley & Sons, Ltd.
Justice and job engagement: The role of senior management trust
Authors: Haynie Jeffrey J. , Mossholder Kevin W. , Harris Stanley G.
Published: January 2016

We examined whether job engagement mediated the effects of organizational justice dimensions on work behaviors and attitudes. Considering distributive and procedural justice from a motivational perspective, we proposed that job engagement would mediate these two dimensions' relations with the work outcomes of task performance, organizational citizenship behavior, and job satisfaction. We also expected this mediation effect would be magnified when senior management trust (SMT) was high. Our results showed that the simple mediation model was supported only for distributive justice. Alternatively, the indirect effect of procedural justice on work outcomes through job engagement was significant only when SMT was high. Implications of our findings and areas for future research are discussed. Copyright © 2016 John Wiley & Sons, Ltd.
Selecting representative climate models for climate change impact studies: an advanced envelope‐based selection approach
Authors: Lutz Arthur F. , ter Maat Herbert W. , Biemans Hester , Shrestha Arun B. , Wester Philippus , Immerzeel Walter W.
Published: January 2016

Climate change impact studies depend on projections of future climate provided by climate models. The number of climate models is large and increasing, yet limitations in computational capacity make it necessary to compromise the number of climate models that can be included in a climate change impact study. The selection of climate models is not straightforward and can be done by following different methods. Usually, the selection is either based on the entire range of changes in climatic variables as projected by the total ensemble of available climate models or on the skill of climate models to simulate past climate. The present study combines these approaches in a three‐step sequential climate model selection procedure: (1) initial selection of climate models based on the range of projected changes in climatic means, (2) refined selection based on the range of projected changes in climatic extremes and (3) final selection based on the climate model skill to simulate past climate. This procedure is illustrated for a study area covering the Indus, Ganges and Brahmaputra river basins. Subsequently, the changes in climate between 1971–2000 and 2071–2100 are analysed, showing that the future climate projections in this area are highly uncertain but that changes are imminent.
Validation of laser‐induced thermal acoustics for chemically reacting H2/air free jets
Authors: Hell A. , Förster F. J. , Weigand B.
Published: January 2016

The scramjet engine is a promising propulsion concept for future space transportation systems. To enhance the engine efficiency, a strong understanding of combustion mechanisms is essential. Laser‐induced thermal acoustics (LITA) – a seedless, non‐intrusive measurement technique – is an auspicious technique for the investigation of supersonic combustion. Here, we present two validation cases and first LITA measurements in a chemically reacting hydrogen/air free jet. The first validation case is the investigation of premixed methane/air and hydrogen/air flames, produced with a commercially available flat flame burner. The comparison with coherent anti‐Stokes Raman spectroscopy measurements resulted in a deviation between the two measurement techniques smaller than the uncertainty of the techniques. The second validation case is the investigation of hot, supersonic air/air free jets at total temperatures of Tt = 1050 K and Tt = 1300 K. The comparison with computational fluid dynamics predictions shows a reasonable agreement with a maximum deviation of 13.9% for the free jet with a temperature of Tt = 1300 K and a good agreement with a maximum deviation of 4.4% for the free jet with a temperature of Tt = 1050 K. The LITA measurements in a chemically reacting hydrogen/air free jet showed a good reproduction of the flame position determined from an OH∗ image. For the presented investigations, we used a homodyne, resonant LITA setup with a pulsed interrogation beam. Copyright © 2016 John Wiley & Sons, Ltd.
Separation analysis of macrolide antibiotics with good performance on a positively charged C18HCE column
Authors: Wei Jie , Shen Aijin , Yan Jingyu , Jin Gaowa , Yang Bingcheng , Guo Zhimou , Zhang Feifang , Liang Xinmiao
Published: January 2016

The separation of basic macrolide antibiotics suffers from peak tailing and poor efficiency on traditional silica‐based reversed‐phase liquid chromatography columns. In this work, a C18HCE column with positively charged surface was applied to the separation of macrolides. Compared with an Acquity BEH C18 column, the C18HCE column exhibited superior performance in the aspect of peak shape and separation efficiency. The screening of mobile phase additives including formic acid, acetic acid and ammonium formate indicated that formic acid was preferable for providing symmetrical peak shapes. Moreover, the influence of formic acid content was investigated. Analysis speed and mass spectrometry compatibility were also taken into account when optimizing the separation conditions for liquid chromatography coupled with tandem mass spectrometry. The developed method was successfully utilized for the determination of macrolide residues in a honey sample. Azithromycin was chosen as the internal standard for the quantitation of spiramycin and tilmicosin, while roxithromycin was used for erythromycin, tylosin, clarithromycin, josamycin and acetylisovaleryltylosin. Good correlation coefficients (r2 > 0.9938) for all macrolides were obtained. The intra‐day and inter‐day recoveries were 73.7–134.7% and 80.7–119.7% with relative standard deviations of 2.5–8.0% and 3.9–16.1%, respectively. Outstanding sensitivity with limits of quantitation (S/N ≥ 10) of 0.02–1 μg/kg and limits of detection (S/N ≥ 3) of 0.01–0.5 μg/kg were achieved.
Determination of donepezil in serum samples using molecularly imprinted polymer nanoparticles followed by high‐performance liquid chromatography with ultraviolet detection
Authors: Khansari Mehdi Rajabnia , Bikloo Shahrzad , Shahreza Sara
Published: January 2016

A molecularly imprinted polymer designed for the selective extraction of donepezil from serum samples was synthesized using a noncovalent molecular imprinting approach. The molecularly imprinted polymer was evaluated chromatographically and then its affinity for donepezil was confirmed by solid‐phase extraction. The optimal conditions for solid‐phase extraction were provided by cartridge conditioning using acidified water purified from a Milli‐Q system, sample loading under basic aqueous conditions, clean‐up using acetonitrile, and elution with methanol/tetrahydrofuran. Desirable molecular recognition properties of the molecularly imprinted polymer led to good donepezil recoveries (90–102%). The data indicated that the imprinted polymer has a perfect selectivity and affinity for donepezil and could be used for selective extraction and analysis of donepezil in human serum.
Agarose‐ and alginate‐based biopolymers for sample preparation: Excellent green extraction tools for this century
Authors: Sanagi Mohd Marsin , Loh Saw Hong , Wan Ibrahim Wan Nazihah , Pourmand Neda , Salisu Ahmed , Wan Ibrahim Wan Aini , Ali Imran
Published: January 2016

Recently, there has been considerable interest in the use of miniaturized sample preparation techniques before the chromatographic monitoring of the analytes in unknown complex compositions. The use of biopolymer‐based sorbents in solid‐phase microextraction techniques has achieved a good reputation. A great variety of polysaccharides can be extracted from marine plants or microorganisms. Seaweeds are the major sources of polysaccharides such as alginate, agar, agarose, as well as carrageenans. Agarose and alginate (green biopolymers) have been manipulated for different microextraction approaches. The present review is focused on the classification of biopolymer and their applications in multidisciplinary research. Besides, efforts have been made to discuss the state‐of‐the‐art of the new microextraction techniques that utilize commercial biopolymer interfaces such as agarose in liquid‐phase microextraction and solid‐phase microextraction.
Ultrasound‐assisted magnetic dispersive solid‐phase microextraction: A novel approach for the rapid and efficient microextraction of naproxen and ibuprofen employing experimental design with high‐performance liquid chromatography
Authors: Ghorbani Mahdi , Chamsaz Mahmoud , Rounaghi Gholam Hossein
Published: January 2016

A simple, rapid, and sensitive method for the determination of naproxen and ibuprofen in complex biological and water matrices (cow milk, human urine, river, and well water samples) has been developed using ultrasound‐assisted magnetic dispersive solid‐phase microextraction. Magnetic ethylendiamine‐functionalized graphene oxide nanocomposite was synthesized and used as a novel adsorbent for the microextraction process and showed great adsorptive ability toward these analytes. Different parameters affecting the microextraction were optimized with the aid of the experimental design approach. A Plackett–Burman screening design was used to study the main variables affecting the microextraction process, and the Box–Behnken optimization design was used to optimize the previously selected variables for extraction of naproxen and ibuprofen. The optimized technique provides good repeatability (relative standard deviations of the intraday precision 3.1 and 3.3, interday precision of 5.6 and 6.1%), linearity (0.1–500 and 0.3–650 ng/mL), low limits of detection (0.03 and 0.1 ng/mL), and a high enrichment factor (168 and 146) for naproxen and ibuprofen, respectively. The proposed method can be successfully applied in routine analysis for determination of naproxen and ibuprofen in cow milk, human urine, and real water samples.
Systematic screening and characterization of astragalosides in an oral solution of Radix Astragali by liquid chromatography with quadrupole time‐of‐flight mass spectrometry and Peakview software
Authors: Li Chang‐Yin , Song Hui‐Ting , Liu Shi‐Jia , Wang Qiong , Dai Guo‐Liang , Ding Xuan‐Sheng , Ju Wen‐Zheng
Published: January 2016

Liquid chromatography with quadrupole time‐of‐flight mass spectrometry coupled with automated data analysis by Peakview software was employed to systematically screen and characterize the astragalosides in Radix Astragali, a Chinese medical preparation. The separation was performed on a poroshell 120 SB‐C18 column equipped in a conventional liquid chromatography system. After being separated using a general gradient elution, the analytes were detected by the triple quadrupole time‐of‐flight mass spectrometer in both positive‐ and negative‐ion modes. The mass defect filtering function built in the Peakview software was utilized to rapidly screen the potential ions of interest, while some functions of Peakview such as Formula Finder, XIC manager, and IDA Explorer were employed to facilitate the assignment or characterization of the screened astragalosides. A total of 42 astragalosides were screened and tentatively characterized or assigned, and 20 of them were firstly detected in Radix Astragali. According to the screened astragalosides, acetylation, glycosidation, hydrogenation, oxidation, and hydration were considered to be the major secondary metabolic pathways involved in the formation of the astragalosides. The combination of liquid chromatography with quadrupole time‐of‐flight mass spectrometry and automated Peakview analysis is a feasible and efficient tool to screen and identify the constituents in complex matrices of herbal medicines.
Extracorporeal liver support devices for listed patients
Authors: Lee Karla C. L. , Stadlbauer Vanessa , Jalan Rajiv
Published: January 2016

An alternative to liver transplantation for patients with liver failure remains an unmet need. In acute liver failure, the ideal extracorporeal liver support device (ELSD) would replace the functions of the failing liver in order to permit spontaneous recovery, given the incredible regenerative potential of the liver, negating the need for transplantation. In acute‐on‐chronic liver failure, an ELSD would ideally support hepatic function until a recovery to liver function before acute decompensation or until liver transplantation. In decompensated cirrhosis, an ELSD could again be used to support hepatic function until transplant. In addition, ELSDs may have the potential to treat the multiorgan failure that accompanies liver failure including hepatic encephalopathy, renal failure, and immune dysfunction or indeed potential to promote liver regeneration. Creation of an extracorporeal bioartificial liver able to completely replace liver function remains an unmet need. This review will describe a number of technologies suitable for clinical trials in humans, which have resulted from decades of engineering and biological research to develop a bioreactor able to adequately sustain functional hepatocytes. In addition, this review will describe artificial liver support devices that are primarily designed to replace the detoxifying functions of the liver and will consider the current data available or studies required to support their use in liver failure patients on the transplant waiting list. Liver Transplantation 22 839–848 2016 AASLD.
Relevance of microRNA‐18a and microRNA‐199a‐5p to hepatocellular carcinoma recurrence after living donor liver transplantation
Authors: Morita Kazutoyo , Shirabe Ken , Taketomi Akinobu , Soejima Yuji , Yoshizumi Tomoharu , Uchiyama Hideaki , Ikegami Toru , Yamashita Yo‐ichi , Sugimachi Keishi , Harimoto Norifumi , Itoh Shinji , Ikeda Tetsuo , Maehara Yoshihiko
Published: January 2016

There are few reports about recurrence‐related microRNAs (miRNAs) after liver transplantation (LT) for hepatocellular carcinoma (HCC). The purpose of this study was to identify novel recurrence‐related miRNAs after living donor liver transplantation (LDLT) for HCC. First, we performed microarray analyses of samples from a liver with primary HCC, a liver that was noncancerous, and a liver that had recurrence‐metastasis from 3 patients with posttransplant recurrence. Then we selected miRNAs with consistently altered expression in both primary HCC and recurrence as potential candidates of recurrence‐related miRNAs. Expression of the miRNAs in HCC and noncancerous livers was assessed in 70 HCC patients who underwent LDLT. The target genes regulated by the recurrence‐related miRNAs were identified. MicroRNA‐18a (miR‐18a) expression was increased, and microRNA‐199a‐5p (miR‐199a‐5p) expression was decreased in both primary HCC and recurrence. Increased miR‐18a expression correlated with high levels of tumor markers, large tumor size, and a high recurrence rate. Decreased miR‐199a‐5p expression correlated with high levels of tumor markers, portal venous invasion, and a high recurrence rate. In HCC cells, miR‐18a regulated the expression of tumor necrosis factor alpha–induced protein 3 (TNFAIP3), and miR‐199a‐5p regulated the expression of hypoxia‐inducible factor 1 alpha (HIF1A), vascular endothelial growth factor A (VEGFA), insulin‐like growth factor 1 receptor, and insulin‐like growth factor 2. In conclusion, increased miR‐18a levels and decreased miR‐199a‐5p levels are relevant to HCC recurrence after LDLT. MiR‐18a and miR‐199a‐5p could be novel therapeutic targets of recurrent HCC after LDLT. Liver Transplantation 22 665‐676 2016 AASLD.
Risk analysis of ischemic‐type biliary lesions after liver transplant using octogenarian donors
Authors: Ghinolfi Davide , De Simone Paolo , Lai Quirino , Pezzati Daniele , Coletti Laura , Balzano Emanuele , Arenga Giuseppe , Carrai Paola , Grande Gennaro , Pollina Luca , Campani Daniela , Biancofiore Gianni , Filipponi Franco
Published: January 2016

The use of octogenarian donors to increase the donor pool in liver transplantation (LT) is controversial because advanced donor age is associated with a higher risk of ischemic‐type biliary lesions (ITBL). The aim of this study was to investigate retrospectively the role of a number of different pre‐LT risk factors for ITBL in a selected population of recipients of octogenarian donor grafts. Between January 2003 and December 2013, 123 patients underwent transplantation at our institution with deceased donor grafts from donors of age ≥80 years. Patients were divided into 2 groups based on the presence of ITBL in the posttransplant course. Exclusion criteria were retransplantations, presence of vascular complications, and no availability of procurement liver biopsy. A total of 88 primary LTs were included, 73 (83.0%) with no posttransplant ITBLs and 15 (17.0%) with ITBLs. The median follow‐up after LT was 2.1 years (range, 0.7‐5.4 years). At multivariate analysis, donor hemodynamic instability (hazard ratio [HR], 7.6; P = 0.005), donor diabetes mellitus (HR, 9.5; P = 0.009), and donor age–Model for End‐Stage Liver Disease (HR, 1.0; P = 0.04) were risk factors for ITBL. Transplantation of liver grafts from donors of age ≥80 years is associated with a higher risk for ITBL. However, favorable results can be achieved with accurate donor selection. Donor hemodynamic instability, a donor history of diabetes mellitus, and allocation to higher Model for End‐Stage Liver Disease score recipient all increase the risk of ITBL and are associated with worse graft survival when octogenarian donors are used. Liver Transplantation 22 588‐598 2016 AASLD.
Dense codense predicates and the NTP2
Authors: Berenstein Alexander , Kim Hyeung‐Joon
Published: January 2016

We show that if T is any geometric theory having the NTP2 then the corresponding theories of lovely pairs of models of T and of H‐structures associated to T also have the NTP2. We also prove that if T is strong then the same two expansions of T are also strong.
Computable axiomatizability of elementary classes
Authors: Sinclair Peter
Published: January 2016

The goal of this paper is to generalise Alex Rennet's proof of the non‐axiomatizability of the class of pseudo‐o‐minimal structures. Rennet showed that if is an expansion of the language of ordered fields and is the class of pseudo‐o‐minimal ‐structures (‐structures elementarily equivalent to an ultraproduct of o‐minimal structures) then is not computably axiomatizable. We give a general version of this theorem, and apply it to several classes of structures.
A note on tall cardinals and level by level equivalence
Authors: Apter Arthur W.
Published: January 2016

Starting from a model “κ is supercompact” + “No cardinal is supercompact up to a measurable cardinal”, we force and construct a model such that “κ is supercompact” + “No cardinal is supercompact up to a measurable cardinal” + “δ is measurable iff δ is tall” in which level by level equivalence between strong compactness and supercompactness holds. This extends and generalizes both [, Theorem 1] and the results of .
Exfoliation of Boron Nitride Platelets by Enhanced Interfacial Interaction with Polyethylene
Authors: Tajaddod Navid , Song Kenan , Green Emily C. , Zhang Yiying , Minus Marilyn L.
Published: January 2016

Hexagonal boron nitride (BN) platelets are used for fabrication of ultrahigh molecular weight polyethylene (UHMWPE)/BN composite fibers using a flow‐crystallization process. As‐spun fibers are subsequently drawn near the UHMWPE melting temperature. Interfacial crystallization of UHMWPE is observed on the surfaces of the BN platelets. Both X‐ray and Raman spectroscopy analysis of the drawn composite fibers show a significant decrease in the intensity of the signature BN peaks associated with the platelet interlayer spacing, as compared to undrawn samples. This suggests exfoliation of the BN platelets occurs during the fiber hot‐drawing process. Exfoliation of BN platelets is induced due to interfacial stress transfer between both components (i.e., UHMPWE and BN) within the composites. This stress transfer is facilitated by molecular rearrangement of polymer matrix during drawing (i.e., unfolding of the polymer chain). The changes in micro‐ and nanoscale morphologies due to unfolding of the polymer chains as well as simultaneous exfoliation of the BN platelets are fully characterized and show that these structural changes provide insight for understanding the property trends of the fibers.

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Employing Nitrogen Doping as Innovative Technique to Improve Broadband Dielectric Properties of Carbon Nanotube/Polymer Nanocomposites
Authors: Arjmand Mohammad , Ameli Amir , Sundararaj Uttandaraman
Published: January 2016

Undoped carbon nanotubes (CNTs) and N‐CNTs are synthesized by chemical vapor deposition using Fe catalyst, and then melt‐mixed in an APAM mixer with polyvinylidene fluoride (PVDF) to prepare the nanocomposites. The morphology, crystallinity, aspect ratio, nitrogen content, and nitrogen bonding type of CNTs, and the broadband dielectric properties of undoped CNT/PVDF and N‐CNT/PVDF nanocomposites are analyzed. The results show that while undoped CNTs present a crystalline structure with open channels, doping with nitrogen results in CNTs with a bamboo‐like configuration, inferior crystallinity, smaller length, and larger dia­meter. The N‐CNT/PVDF nanocomposites, thus, have a higher percolation threshold (≈ 3.5 wt%) compared to that of the undoped CNT/PVDF nanocomposites (≈ 0.5 wt%). Comparison of the broadband dielectric properties of the generated nanocomposites reveals that nitrogen doping improved the dielectric properties in the insulative region. This is ascribed to the role of nitrogen atoms and their sequent defects in the nanotubes, which act as scattering centers and provide additional polarization sites. For instance, 1.0 wt% N‐CNT/PVDF nanocomposites exhibit a real permittivity of ε′ = 22 and a dissipation factor of tan δ = 0.03 at 1 kHz, a combination superior to that of 0.5 wt% undoped CNT/PVDF nanocomposite with ε′ = 11.2 and tan δ = 3.8, and 1.0 wt% undoped CNT/PVDF nanocomposites with ε′ = 40 and tan δ = 1.4 × 105.

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Transcriptome profiling in oral cavity and esophagus tissues from (S)‐N′‐nitrosonornicotine‐treated rats reveals candidate genes involved in human oral cavity and esophageal carcinogenesis
Authors: Khammanivong Ali , Anandharaj Arunkumar , Qian Xuemin , Song Jung Min , Upadhyaya Pramod , Balbo Silvia , Bandyopadhyay Dipankar , Dickerson Erin B. , Hecht Stephen S. , Kassie Fekadu
Published: January 2016

Recently, we have shown that (S)‐N'‐Nitrosonornicotine [(S)‐NNN], the major form of NNN in tobacco products, is a potent oral cavity and esophageal carcinogen in rats. To determine the early molecular alterations induced by (S)‐NNN in the oral and esophageal mucosa, we administered the carcinogen to rats in the drinking water for 10 wk and global gene expression alterations were analyzed by RNA sequencing. At a false discovery rate P‐value < 0.05 and fold‐change ≥2, we found alterations in the level of 39 genes in the oral cavity and 69 genes in the esophagus. Validation of RNA sequencing results by qRT‐PCR assays revealed a high cross‐platform concordance. The most significant impact of exposure to (S)‐NNN was alteration of genes involved in immune regulation (Aire, Ctla4, and CD80), inflammation (Ephx2 and Inpp5d) and cancer (Cdkn2a, Dhh, Fetub B, Inpp5d, Ly6E, Nr1d1, and Wnt6). Consistent with the findings in rat tissues, most of the genes were deregulated, albeit to different degrees, in immortalized oral keratinocytes treated with (S)‐NNN and in non‐treated premalignant oral cells and malignant oral and head and neck squamous cells. Furthermore, interrogation of TCGA data sets showed that genes deregulated by (S)‐NNN in rat tissues (Fetub, Ly6e, Nr1d1, Cacna1c, Cd80, and Dgkg) are also altered in esophageal and head and neck tumors. Overall, our findings provide novel insights into early molecular changes induced by (S)‐NNN and, therefore, could contribute to the development of biomarkers for the early detection and prevention of (S)‐NNN‐associated oral and esophageal cancers. © 2016 Wiley Periodicals, Inc.
Spatane diterpinoid from the brown algae, Stoechospermum marginatum induces apoptosis via ROS induced mitochondrial mediated caspase dependent pathway in murine B16F10 melanoma cells
Authors: Velatooru Loka Reddy , Baggu Chinna Babu , Janapala Venkateswara Rao
Published: January 2016

Spatane diterpinoids isolated from the brown marine algae Stoechospermum marginatum were known to have cytotoxic effects in human cancerous cell lines and murine melanoma cells; the underling apoptotic mechanism of diterpinoids still remains unclear so far. Thus, in the present study, the apoptotic mechanism of a spatane diterpinoid, 5(R), 19‐diacetoxy‐15,18(R and S), dihydro spata‐13, 16(E)‐diene (DDSD) was investigated mainly in B16F10 melanoma cells because they were most susceptible to DDSD than THP1, U937, COLO205, and HL60 cells. The treatment of B6F10 cells with DDSD resulted in morphological alterations, nuclear condensation, and DNA fragmentation, which leads to cell growth inhibition in a concentration‐dependent manner. Data indicate that DDSD induced the generation of ROS, consequentially caused alteration in Bax/Bcl‐2 ratio that disrupted the inner mitochondrial transmembrane potential (ΔΨm) resulting in cytochrome c redistribution to the cytoplasm and activation of caspase‐mediated apoptotic pathway. Flow cytometric analysis clearly indicated that the DDSD inducing phosphatidylserine externalization and mediated “S‐phase” arrest in cell cycle. In addition, results also found that DDSD induced apoptosis through deregulating PI3K/AKT signaling pathway. The anti‐tumor activity of DDSD was evaluated in C57BL/6 mice bearing B16F10 melanoma. It effectively inhibited tumor growth (volume and weight) in a dose dependent manner, yet without apparent toxic effects. Morphology and apoptotic status of tumor tissues in the treated mice were assessed by microscopy and TUNEL assay, respectively. Our study shows a therapeutic potential of DDSD for the treatment of malignant melanoma and a new source of anticancer drugs. © 2016 Wiley Periodicals, Inc.
Fast and simplified mapping of mean axon diameter using temporal diffusion spectroscopy
Authors: Xu Junzhong , Li Hua , Li Ke , Harkins Kevin D. , Jiang Xiaoyu , Xie Jingping , Kang Hakmook , Dortch Richard D. , Anderson Adam W. , Does Mark D. , Gore John C.
Published: January 2016

Mapping axon diameter is of interest for the potential diagnosis and monitoring of various neuronal pathologies. Advanced diffusion‐weighted MRI methods have been developed to measure mean axon diameters non‐invasively, but suffer major drawbacks that prevent their direct translation into clinical practice, such as complex non‐linear data fitting and, more importantly, long scanning times that are usually not tolerable for most human subjects. In the current study, temporal diffusion spectroscopy using oscillating diffusion gradients was used to measure mean axon diameters with high sensitivity to small axons in the central nervous system. Axon diameters have been found to be correlated with a novel metric, DDR⊥ (the rate of dispersion of the perpendicular diffusion coefficient with gradient frequency), which is a model‐free quantity that does not require complex data analyses and can be obtained from two diffusion coefficient measurements in clinically relevant times with conventional MRI machines. A comprehensive investigation including computer simulations and animal experiments ex vivo showed that measurements of DDR⊥ agree closely with histological data. In humans in vivo, DDR⊥ was also found to correlate well with reported mean axon diameters in human corpus callosum, and the total scan time was only about 8 min. In conclusion, DDR⊥ may have potential to serve as a fast, simple and model‐free approach to map the mean axon diameter of white matter in clinics for assessing axon diameter changes. Copyright © 2016 John Wiley & Sons, Ltd.