bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exploring the efficacy of different electric field models in driving a model of the plasmasphere
Authors: Ridley A. J. , Dodger A. M. , Liemohn M. W. 
Published: June 2014

AbstractThe dynamics of the plasmasphere are strongly controlled by the inner magnetospheric electric field. In order to capture realistically the erosion of the nightside plasmapause and the formation of the drainage plume in a model of the plasmasphere, the electric field must be accurate. This study investigates how well five different electric field models drive the Dynamic Global Core Plasma Model during eight storm periods. The five electric field models are the Volland‐Stern analytic formula with Maynard‐Chen Kpdependence, two versions of the Weimer statistical models (96 and 05), and two versions of the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) technique using magnetometer and DMSP satellite data. Manually extracted plasmapause locations from images taken by the EUV instrument on the Imager for Magnetopause‐to‐Aurora Global Exploration (IMAGE) satellite, as described by Goldstein et al. (2005), were compared to the simulation results throughout the main phase of the eight events. Three methods of calculating the plasmapause were employed to determine the best fit to EUV data, using the maximum gradient, a constant density contour (fit method), and the location in which the modeled density fell significantly below the specified saturation density for the given radial position (saturation method). It was found that the simulations driven by the Weimer (1996) model produced the best fit overall and that the fit and saturation methods worked best for matching the model results to the observations.
Impact of vertical mixing on sea surface pCO2 in temperate seasonally stratified shelf seas
Authors: Rippeth T. P. , Lincoln B. J. , Kennedy H. A. , Palmer M. R. , Sharples J. , Williams C. A. J. 
Published: June 2014

AbstractA key parameter in determining the exchange of CO2 across the ocean‐atmosphere interface is the sea surface partial pressure of carbon dioxide (pCO2). Temperate seasonally stratified shelf seas represent a significant sink for atmospheric CO2. Here an analytical model is used to quantify the impact of vertical mixing across the seasonal thermocline on pCO2. The model includes the impacts of the resultant dissolved inorganic carbon, heat, salt, and alkalinity fluxes on the solubility of CO2 and the effect of the inorganic carbon sink created by the primary production fuelled by the flux of limiting nutrient. The results indicate that diapycnal mixing drives a modest but continuous change in pCO2 of order 1–10 µatm d−1. In quantifying the individual impacts of the fluxes of the different parameters, we find that the impact of the fluxes of DIC and nitrate fluxes dominate. In consequence, both the direction and magnitude of the change in pCO2 are strongly dependent on the C:N uptake ratio in primary production. While the smaller impacts of the heat and salt fluxes tend to compensate for each other at midshelf locations, the heat flux dominates close to the shelf break. The analysis highlights the importance of the accurate parameterization of the C:N uptake ratio, the surface‐mixed layer depth, and the TKE dissipation rate within the seasonal thermocline in models to be used to predict the air‐sea exchange of carbon dioxide in these regimes. The results implicate storms as key periods of pCO2 perturbation.
Manipulating Natural Product Biosynthetic Pathways via DNA Assembler
Authors: Shao Zengyi , Zhao Huimin 
Published: June 2014

AbstractDNA assembler is an efficient synthetic biology method for constructing and manipulating biochemical pathways. The rapidly increasing number of sequenced genomes provides a rich source for discovery of gene clusters involved in synthesizing new natural products. However, both discovery and economical production are hampered by our limited knowledge in manipulating most organisms and the corresponding pathways. By taking advantage of yeast in vivo homologous recombination, DNA assembler synthesizes an entire expression vector containing the target biosynthetic pathway and the genetic elements needed for DNA maintenance and replication. Here we use the spectinabilin clusters originated from two hosts as examples to illustrate the guidelines of using DNA assembler for cluster characterization and silent cluster activation. Such strategies offer unprecedented versatility in cluster manipulation, bypass the traditional laborious strategies to elicit pathway expression, and provide a new platform for de novo cluster assembly and genome mining for discovering new natural products. Curr. Protoc. Chem. Biol. 6:65‐100 © 2014 by John Wiley & Sons, Inc.
Synthesis of Hydrogen‐Bond Surrogate α‐Helices as Inhibitors of Protein‐Protein Interactions
Authors: Miller Stephen E. , Thomson Paul F. , Arora Paramjit S. 
Published: June 2014

AbstractThe α‐helix is a prevalent secondary structure in proteins and is critical in mediating protein‐protein interactions (PPIs). Peptide mimetics that adopt stable helices have become powerful tools for the modulation of PPIs in vitro and in vivo. Hydrogen‐bond surrogate (HBS) α‐helices utilize a covalent bond in place of an N‐terminal i to i+4 hydrogen bond and have been used to target and disrupt PPIs that become dysregulated in disease states. These compounds have improved conformational stability and cellular uptake as compared to their linear peptide counterparts. The protocol presented here describes current methodology for the synthesis of HBS α‐helical mimetics. The solid‐phase synthesis of HBS helices involves solid‐phase peptide synthesis with three key steps involving incorporation of N‐allyl functionality within the backbone of the peptide, coupling of a secondary amine, and a ring‐closing metathesis step. Curr. Protoc. Chem. Biol. 6:101‐116 © 2014 by John Wiley & Sons, Inc.
Decentralized adaptive command following and disturbance rejection for subsystems with local full‐state feedback
Authors: Polston J. Daniel , Hoagg Jesse B. 
Published: June 2014

SummaryWe present a decentralized model reference adaptive control method, where each local controller uses full‐state feedback from the local subsystem. The controller is strictly decentralized, meaning that no information (including reference‐model trajectories) is shared between local controllers. This decentralized controller achieves stabilization, command following, and disturbance rejection provided that the reference‐model commands and the disturbances are sinusoidal with known spectrum. The controller is effective for multi‐input subsystems with arbitrarily large subsystem interconnections. Copyright © 2014 John Wiley & Sons, Ltd.
Brief Communication: Seasonality of diet composition is related to brain size in New World Monkeys
Authors: van Woerden Janneke T. , van Schaik Carel P. , Isler Karin 
Published: June 2014

ABSTRACTNew World monkeys exhibit a more pronounced variability in encephalization than other primate taxa. In this comparative study, we tested two current hypotheses on brain size evolution, the Expensive Brain hypothesis and the Cognitive Buffer hypothesis, in a sample of 21 platyrrhine species. A high degree of habitat seasonality may impose an energetic constraint on brain size evolution if it leads to a high variation in caloric intake over time, as predicted by the Expensive Brain Hypothesis. However, simultaneously it may also provide the opportunity to reap the fitness benefits of increased cognitive abilities, which enable the exploitation of high‐quality food resources even during periods of scarcity, as predicted by the Cognitive Buffer hypothesis. By examining the effects of both habitat seasonality and the variation in monthly diet composition across species, we found support for both hypotheses, confirming previous results for catarrhine primates and lemurs. These findings are in accordance with an energetic and ecological view of brain size evolution. Am J Phys Anthropol 154:628–632, 2014. © 2014 Wiley Periodicals, Inc.
Thermal decomposition of energetic thermoplastic elastomers of poly(glycidyl nitrate)
Authors: Zhang Zaijuan , Wang Gang , Luo Nan , Huang Muhua , Jin Miaomiao , Luo Yunjun 
Published: June 2014

ABSTRACTEnergetic thermoplastic elastomers (ETPEs) are futuristic binders for propellant/explosive formulations. Poly(glycidyl nitrate) (PGN)‐based ETPEs have excellent performance, including a high energy and high oxygen content. PGN‐based ETPEs were synthesized on PGN as a soft segment and hexamethylene diisocyanate extended 1,4‐butanediol as a hard segment by a prepolymerization method. The thermal behavior of the PGN‐based ETPEs was investigated by thermogravimetric analysis (TGA) and derivative thermogravimetry. A fitting strategy was adopted to study every stage of decomposition. The results show that the ETPEs had four main decomposition processes, and the peaks of each stage were at 212, 262, 322, and 414°C. The gas products were tested by TGA/Fourier transform infrared spectroscopy/mass spectrometry, and the main gas products of the samples were N2O, CH2O, C2H4O, and CO2. The previous results indicate the proposed mechanism of thermal decomposition. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2014,131, 40965.
Monodispersed composite particles prepared via emulsifier‐free emulsion polymerization using waterborne polyurethane as microreactors
Authors: Zhuge Wenna , Pan Mingwang , Chang Yanning , Yuan Jinfeng , Wang Xiaomei , Sun Caili , Zhang Guanglin 
Published: June 2014

ABSTRACTMonodispersed polystyrene particles in submicrometer size were intriguingly prepared through emulsifier‐free batch‐seeded emulsion polymerization using nonmonodispersed waterborne polyurethane (WBPU) beads as microreactors. Different feed ratios of styrene (St)/WBPU for the preparation of composite particles were investigated, and the size–growth course was experimentally followed. The morphology and dispersity of the particles were characterized by scanning electron microscopy together with dynamic laser scattering particle size analyzer. Their inside structure was further characterized by transmission electron microscopy with ultramicrotomy combined with X‐ray photoelectron spectroscopy for the composite particles' surface analysis. The probable grafting polymerization of St from WBPU was verified by Fourier transform infrared spectroscopy and nuclear magnetic resonance instrument. The obtained composite particles were again employed as the seeds in the emulsion copolymerization of methyl methacrylate. As a result, the formed multilayered composite particles with reverse core–shell structure were also monodispersed and spherical. The mechanism of the formation of the monodispersed particles was proposed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40985.
Study on quaternary ammonium modified tentacle‐type cellulose beads and its adsorption for
Authors: Zhang Na , Zhou Cheng‐Xianyi , Xie Tong‐Hui , Zhang Yong‐Kui 
Published: June 2014

ABSTRACTA novel anion exchange resin based on cellulose has been prepared to adsorb
for the urgent demand of silver and the high toxicity of metal‐cyanide complexes. Quaternary ammonium groups were grafted onto cellulose beads as main active sites in tentacle‐type through a series of chemical reactions. The substitution degree of each reaction was determined to be about 0.854, 2.125, and 2.899 mmol g−1, respectively. The resin exhibited excellent spherical shape with microporous structure by the observation of optical microscopy and scanning electron microscope. Moreover, the adsorption experiments demonstrated the adsorption was fast in alkaline condition. Fitting the data into isotherm and kinetic models gave the conclusion that the adsorption behavior matched better with Langmuir model and pseudo‐second‐order kinetic in initial time followed pseudo‐first‐order kinetic model in later phase. The equilibrium adsorption capacity was determined to be 3.016 mmol g−1. With the advantages of high capacity, short equilibrium time, and alkaline resistance, the resin would be considered to a top‐priority adsorbent for the separation of
. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40987.
Optimization of amphiphobic structural surface thickness in relation to its functionality on stainless steel plates
Authors: Yuan Wei‐Li , Su Chi‐Jung , Lei Chien‐Ming , Mou Chun‐Yueh 
Published: June 2014

ABSTRACTFluorine‐based amphiphobic coatings have been widely used in commercial textiles to provide water‐ and oil‐repelling abilities. However, few reports from the literature survey have discussed the surface structural effects of the coated substrate on amphiphobicity. In this research, various thickness amphiphobic coatings based on mixed epoxy, tetraethylorthosilicate, and a particular alkoxysilane with fluorinated side chains (F‐silane) were deposited on Grade 420 stainless steel plates. Film amphiphobicity is characterized by measuring the water and oil contact angles of the coating. Film morphology is examined using atomic force microscopy. The deposited films free of F‐silane are thinner than 150 nm. The films become thick at high F‐silane volume percentage with the surface cavities, ridges, and granules being masked out. On the addition of F‐silane, the water contact angle of the deposited films increases up to 105° and then reaches a plateau of ∼ 107° with increasing F‐silane. In contrast, the oil contact angle increases up to 60° at first and then slowly declines with the F‐silane concentration. The total drop of oil contact angle by ∼ 20° was attributed to the masking out of surface features on film thickening. This indicates that the surface oleophobicity depends on surface structures. Therefore, improving surface amphiphobicity correlates with creating more refined multiscale surface structures during the industrial manufacturing process of steel plate, prior to surface modification by F‐silane. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41003.
The effect of modifier contents of polyvinyl pyrrolidone on the enhanced dielectric and microwave absorbing properties of multiwalled carbon nanotubes
Authors: Zhang Aibo , Cao Xiufen , Tang Meng , zheng Yaping , Lu Zhengbin , Shen Yongtao 
Published: June 2014

ABSTRACT:Polyvinyl pyrrolidone (PVP) polymers were used as non‐covalent modifiers to modify the surface of multi‐walled carbon nanotubes (MWNTs) by ultrasonic dispersion method. The transmission electron microscope results suggest that a layer of polymers is wrapped on the surface of MWNTs, and the thickness is about 2.5 nm. The addition of PVP helps to facilitate uniform distribution of MWNTs and increases the interfacial multipoles formed between PVP and MWNTs, which plays an important role in the regulation of the dielectric parameter and the enhancement of the microwave absorbing properties. The effects of PVP loadings and thickness of PVP/MWNTs hybrids on the dielectric parameter of MWNTs are investigated. The microwave absorbing properties are calculated from the dielectric constants. The results show that the maximum reflection loss is −26.27 dB at 7.8 GHz while the loading of PVP on MWNTs is 8.0 wt % with a thickness of 3.0 mm. These results suggest that the PVP contents and absorber thickness are important factors for the improvement of dielectric loss and microwave absorption properties of MWNTs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41007.
Synthesis, structure, and characterization of glyoxal‐urea‐formaldehyde cocondensed resins
Authors: Deng Shuduan , Pizzi Antonio , Du Guanben , Zhang Jizhi , Zhang Jun 
Published: June 2014

ABSTRACTTo decrease the formaldehyde emission of urea‐formaldehyde (UF) bonded products at source, monomethylol urea (MMU) was chosen to react with glyoxal (G), a nonvolatile and nontoxic aldehyde, to prepare a novel glyoxal‐urea‐formaldehyde (GUF) cocondensed resin. The GUF resins were synthesized with different MMU/G molar ratios, and the basic properties were tested. The GUF resins were characterized by ultraviolet‐visible spectroscopy, Fourier transform infrared spectroscopy, carbon‐13 nuclear magnetic resonance spectroscopy and matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI‐TOF‐MS). The results show that the synthesized GUF resins remain stable for at least 10 days at ambient temperature. Conjugated structures, and large amounts of OH, NH, CN, and CO groups with different levels of substitution exist in the GUF resin. There are two repeating motives in the MALDI‐TOF‐MS spectrum of the GUF resin, one of 175 ±1 Da and a second one of 161 ± 1 Da. Moreover, the peaks due to the dehydration condensation reaction of MMU also appear in the spectra. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41009.
Study the factors affecting the performance of organic–inorganic hybrid coatings
Authors: Li Weili , Huang Dong , Xing XinYu , Tang Jijun , Xing Yujin , Li Xiujuan , Zhang Jide 
Published: June 2014

ABSTRACTIn this article, a series of hybrid organic–inorganic coatings based on silica‐epoxy composite resins were prepared with the sol‐gel method by using γ‐aminopropyl triethoxysilane as a coupling agent. Especially, the research emphasized on the factors that influenced on the properties of the prepared hybrid coatings. Firstly, epoxy resin was reacted with γ‐aminopropyl triethoxysilane at a specific feeding molar ratio; subsequently, the asprepared sol–gel precursor was cohydrolyzed with tetraethoxysilane (TEOS) at various contents to afford chemical bondings to form silica networks and give a series of organic–inorganic hybrid coatings. They were loaded and cured on steel panels and characterized for FTIR, TGA, DSC, water contact angles (WCA), pencil hardness, surface & three‐dimensional morphological studies, and potentiodynamic polarization tests. The surfaces of the hybrid coatings showed Sea‐Island or Inverting Sea‐Island morphologies at a certain relative content of two components, which made the coatings possess hydrophobic property. Due to the contribution of organic and inorganic components, the prepared hybrid coatings possess a lot of properties such as pencil hardness, thermotolerance, and corrosion resistance. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41010.
Behavioral Health Homes: A Model for Implementation of the Affordable Care Act
Authors: Sacco Frank C. , Twemlow Stuart W. 
Published: June 2014

ABSTRACTThis paper outlines a model of designing a service delivery system for a targeted population of high‐risk Medicaid families. The Affordable Care Act (ACA) has created a new focus on a population that has high behavioral health and medical needs. Medicaid families are segmented into categories based on the criteria outlined in the ACA and a service delivery system is suggested. The model calls for the creation of specialty services in the community that reach out to high‐risk families and provide ongoing integrated care that strives for improved health outcomes. The psychoanalytic principles used in attachment theory and power dynamics are offered as a method of creating new responses to complicated health and behavioral health problems in Medicaid families. Copyright © 2014 John Wiley & Sons, Ltd.
Enhancing fatty acid ethyl ester production in Saccharomyces cerevisiae through metabolic engineering and medium optimization
Authors: Thompson R. Adam , Trinh Cong T. 
Published: June 2014

ABSTRACTBiodiesels in the form of fatty acyl ethyl esters (FAEEs) are a promising next generation biofuel due to their chemical properties and compatibility with existing infrastructure. It has recently been shown that expression of a bacterial acyl‐transferase in the established industrial workhorse Saccharomyces cerevisiae can lead to production of FAEEs by condensation of fatty acyl‐CoAs and ethanol. In contrast to recent strategies to produce FAEEs in S. cerevisiae through manipulation of de novo fatty acid biosynthesis or a series of arduous genetic manipulations, we introduced a novel genetic background, which is comparable in titer to previous reports with a fraction of the genetic disruption by aiming at increasing the fatty acyl‐CoA pools. In addition, we combined metabolic engineering with modification of culture conditions to produce a maximum titer of over 25 mg/L FAEEs, a 40% improvement over previous reports and a 17‐fold improvement over our initial characterizations. Biotechnol. Bioeng. 2014;111: 2200–2208. © 2014 Wiley Periodicals, Inc.
A simple method for eliminating fixed‐region interference of aptamer binding during SELEX
Authors: Ouellet Eric , Lagally Eric T. , Cheung Karen C. , Haynes Charles A. 
Published: June 2014

ABSTRACTStandard libraries for systematic evolution of ligands by exponential enrichment (SELEX) typically utilize flanking regions that facilitate amplification of aptamers recovered from each selection round. Here, we show that these flanking sequences can bias the selection process, due in part to their ability to interfere with the fold or function of aptamers localized within the random region of the library sequence. We then address this problem by investigating the use of complementary oligonucleotides as a means to block aptamer interference by each flanking region. Isothermal titration calorimetry (ITC) studies are combined with fold predictions to both define the various interference mechanisms and assess the ability of added complementary oligonucleotides to ameliorate them. The proposed blocking strategy is thereby refined and then applied to standard library forms of benchmark aptamers against human α‐thrombin, streptavidin, and vascular endothelial growth factor (VEGF). In each case, ITC data show that the new method effectively removes fixed‐region mediated interference effects so that the natural binding affinity of the benchmark aptamer is completely restored. We further show that the binding affinities of properly functioning aptamers within a selection library are not affected by the blocking protocol, and that the method can be applied to various common library formats comprised of different flanking region sequences. Finally, we present a rapid and inexpensive qPCR‐based method for determining the mean binding affinity of retained aptamer pools and use it to show that introduction of the pre‐blocking method into the standard SELEX protocol results in retention of high‐affinity aptamers that would otherwise be lost during the first round of selection. Significant enrichment of the available pool of high‐affinity aptamers is thereby achieved in the first few rounds of selection. By eliminating single‐strand (aptamer‐like) structures within or involving the fixed regions, the technique is therefore shown to isolate aptamer sequence and function within the desired random region of the library members, and thereby provide a new selection method that is complementary to other available SELEX protocols. Biotechnol. Bioeng. 2014;111: 2265–2279. © 2014 Wiley Periodicals, Inc.