bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Bismuth Modified Carbon Thread Electrode for Simultaneous and Highly Sensitive Cd (II) and Pb (II) Determination
Authors: Saeed Ayman Ali , Singh Baljit , Nooredeen Abbas Mohammed , Dempsey Eithne 
Published: May 2016

AbstractBismuth film modified and chemically activated carbon micro‐thread electrodes were investigated for the simultaneous determination of Cd(II) and Pb(II) using square wave anodic stripping voltammetry. The carbon thread electrode was characterised using both surface and electrochemical techniques. Electrochemical impedance spectroscopy (EIS) studies demonstrated that the H2SO4/IPA‐treated carbon thread electrode showed a much improved resistance response (Rct=23 Ω) compared to the IPA‐untreated carbon thread (Rct=8317 Ω). Furthermore, parameters such as the effect of deposition potential, deposition time and Bi(III) concentration were explored using square wave voltammetry. Detection limits (S/N=3) for Cd(II) and Pb(II) were found to be 1.08 µg L−1 and 0.87 µg L−1, respectively and response was found to be linear over the range 5–110 µg L−1. The proposed Bi/IPA‐treated carbon thread electrode exhibited a high selectivity towards Cd(II) and Pb(II) even in the presence of a range of heavy metals and is capable of repetitive and reproducible measurements, being attributed to the high surface area, geometry and electrode treatment characteristics. The proposed metal ion sensor was employed to determine cadmium and lead in river water samples and % RSD was found to be 5.46 % and 5.93 % for Cd(II) and Pb(II) respectively (n=3). Such facile sensing components favour the development of cost effective portable devices for environmental sample analysis and electrochemical applications.
Pilot‐assisted channel estimation with MSE‐optimal thresholding for OFDM systems
Authors: Peng Yuexing , Alexandropoulos George C. , Li Yonghui 
Published: May 2016

AbstractA transform‐domain (TD) pilot‐assisted channel estimation (PACE) technique to minimize the mean squared error (MSE) performance for orthogonal frequency division multiplexing systems is presented in this paper. The proposed technique utilizes a specially designed pilot pattern, according to which the computationally intensive inverse matrix operation needed to obtain the PACE vector is efficiently replaced by a matrix transposition. Assuming a block frequency‐selective Rayleigh fading channel model, we first analyse the detection reliability of the positions of the most significant taps (MSTs) of the channel impulse response and its effect on the MSE performance of time‐domain PACE. Because the error probability of the MSTs' position estimation plays a significant role in the MSE performance and, as such, all unreliably estimated MSTs should be discarded from the final PACE vector, an MSE‐optimal thresholding approach for MSTs is introduced. With this approach, all estimated MSTs whose amplitude is less than a detection reliability‐based threshold are discarded. A closed‐form expression and a lower bound for the MSE performance of the proposed TD PACE technique with MSE‐optimal thresholding are obtained for block frequency‐selective Rayleigh fading channels. The validity of all derived performance expressions is verified by Monte Carlo simulations. The conducted performance results show that the MSE‐optimal thresholding technique considerably outperforms the existing PACE techniques. Copyright © 2016 John Wiley & Sons, Ltd.
Modeling the resonant frequency of compact microstrip antenna by the PSO‐based SVM with the hybrid kernel function
Authors: Fei‐Yan Sun , Yu‐Bo Tian , Zuo‐Lin Ren 
Published: May 2016

SummaryA methodology based on the support vector machine (SVM) combined with a hybrid kernel function (HKF) for accurately modeling the resonant frequencies of the compact microstrip antenna (MSA) is presented and dedicated to reduce the number of samples and simplify the structure when predicting the resonant frequency of the compact MSA by artificial neural network. The parameters of the SVMs and weight coefficients of the HKF are optimized by means of particle swarm optimization algorithm. In addition, two different kernel functions (KFs), namely polynomial KF (a kind of global KF) and Cauchy KF (a kind of local KF), are employed to overcome the disadvantages of traditional KF. The proposed method is validated by the UCI database. The evaluation results show that the HKF can improve the learning ability and generalization ability of the SVM. Furthermore, the resonant frequencies of a planar inverted F‐shaped antenna and an L‐shaped MSA are modeled by the proposed method. Predictive results with high accuracy demonstrate that the particle swarm optimization‐based SVM with the HKF can improve the prediction accuracy for a small dataset. Copyright © 2016 John Wiley & Sons, Ltd.
Accelerating the pace of discovery in orthopaedic research: A vision toward team science
Authors: Bahney Chelsea S. , Bruder Scott P. , Cain Jarrett D. , Keyak Joyce H. , Killian Megan L. , Shapiro Irving M. , Jones Lynne C. 
Published: May 2016

ABSTRACTThe landscape of basic science in the United States and around the world is changing, and the field of orthopaedic research is positioned to lead by embracing a culture of collaborative, team science that reflects our field's interdisciplinary nature. In this article we hope to address some of the cultural challenges and programmatic barriers that impede a team science approach in the US and suggest opportunities for change. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1673–1679, 2016.
Mulching Affects Soil Properties and Greenhouse Gas Emissions Under Long‐Term No‐Till and Plough‐Till Systems in Alfisol of Central Ohio
Authors: Nawaz Ahmad , Lal Rattan , Shrestha Raj Kumar , Farooq Muhammad 
Published: May 2016

AbstractAgricultural activities emit greenhouse gases (GHGs) and contribute to global warming. Intensive plough tillage (PT), use of agricultural chemicals and the burning of crop residues are major farm activities emitting GHGs. Intensive PT also degrades soil properties by reducing soil organic carbon (SOC) pool. In this scenario, adoption of no‐till (NT) systems offers a pragmatic option to improve soil properties and reduce GHG emission. We evaluated the impacts of tillage systems (NT and PT) and wheat residue mulch on soil properties and GHG emission. This experiment was started in 1989 on a Crosby silt loam soil at Waterman Farm, The Ohio State University, Columbus, Ohio, USA. Mulching reduced soil bulk density and improved total soil porosity. More total carbon (16.16 g kg−1), SOC (8.36 mg L−1) and soil microbial biomass carbon (152 µg g−1) were recorded in soil under NT than PT. Mulch application also decreased soil temperature (0–5 cm) and penetration resistance (0–60 cm). Adoption of long‐term NT reduced the GHG emission. Average fluxes of GHGs under NT were 1.84 g CO2‐C m−2 day−1 for carbon dioxide, 0.07 mg CH4‐C m−2 day−1 for methane and 0.73 mg N2O‐N m−2 day−1 for nitrous oxide compared with 2.05 g CO2‐C m−2 day−1, 0.74 mg CH4‐C m−2 day−1 and 1.41 mg N2O‐N m−2 day−1, respectively, for PT. Emission of nitrous oxide was substantially increased by mulch application. In conclusion, long‐term NT reduced the GHG emission by improving the soil properties. Copyright © 2016 John Wiley & Sons, Ltd.
Gelatin—Hyaluronic Acid Hydrogels with Tuned Stiffness to Counterbalance Cellular Forces and Promote Cell Differentiation
Authors: Poveda‐Reyes Sara , Moulisova Vladimira , Sanmartín‐Masiá Esther , Quintanilla‐Sierra Luis , Salmerón‐Sánchez Manuel , Ferrer Gloria Gallego 
Published: May 2016

Cells interact mechanically with their environment, exerting mechanical forces that probe the extracellular matrix (ECM). The mechanical properties of the ECM determine cell behavior and control cell differentiation both in 2D and 3D environments. Gelatin (Gel) is a soft hydrogel into which cells can be embedded. This study shows significant 3D Gel shrinking due to the high traction cellular forces exerted by the cells on the matrix, which prevents cell differentiation. To modulate this process, Gel with hyaluronic acid (HA) has been combined in an injectable crosslinked hydrogel with controlled Gel–HA ratio. HA increases matrix stiffness. The addition of small amounts of HA leads to a significant reduction in hydrogel shrinking after cell encapsulation (C2C12 myoblasts). We show that hydrogel stiffness counterbalanced traction forces of cells and this was decisive in promoting cell differentiation and myotube formation of C2C12 encapsulated in the hybrid hydrogels.image
Novel polypropyleneβ‐nucleating agent with polyhedral oligomeric silsesquioxane core: synthesis and application
Authors: Barczewski Mateusz , Dobrzyńska‐Mizera Monika , Dutkiewicz Michał , Szołyga Mariusz 
Published: May 2016

AbstractSynthesis and nucleation ability of a novel silsesquioxane‐basedβ‐nucleating agent for isotactic polypropylene (iPP) are presented. A silsesquioxane cage (POSS) was octa‐functionalized with a commercially used nucleating agent, namelyN2,N6‐dicyclohexylnaphthalene‐2,6‐dicarboxamide (NU‐100), and used as a carrier with the ability to promote crystallization ofβ‐phase in polypropylene matrix. Presented results include the synthesis route of theβ‐nucleating agent (SF‐B01) and a description of its nucleation ability in iPP. The influence of SF‐B01 on iPP matrix was examined using differential scanning calorimetry, wide‐angle X‐ray scattering and static tensile tests. Investigations were complemented with polarized light optical microscopy upon non‐isothermal crystallization of composites as well as scanning electron microscopy to qualitatively assess the filler distribution. Polypropylene samples modified with different amounts of NU‐100 were used as reference. Modification carried out with both nucleating agents reveals their comparable efficiency, i.e. a structure rich inβ‐phase is obtained in both cases. © 2016 Society of Chemical Industry
Synthesis of PEGylated poly(amino acid) pentablock copolymers and their self‐assembly
Authors: Iijima Michihiro , Ulkoski David , Sakuma Shunya , Matsukuma Daisuke , Nishiyama Nobuhiro , Otsuka Hidenori , Scholz Carmen 
Published: May 2016

AbstractPentablock copolymers with an ABCBA architecture were synthesized by ring‐opening polymerization of N‐carboxyanhydrides of l‐leucine and γ‐benzyl l‐glutamate using an α, ω‐diamino poly(ethylene glycol) (PEG) as macroinitiator. Three different PEGs with molecular weights of 2000, 4600 and 10 000 Da were used and the poly(amino acid) (PAA) block lengths were set to a combined 10 and 40, respectively, repeat units for p(l‐Leu) and 40 repeat units for p(l‐Glu). The molecular architecture of the resulting pentablock copolymers was determined by the order of monomer addition. The living character of the N‐carboxyanhydride ring‐opening polymerization enables the formation of multiblock copolymers. The degree of polymerization for the PAA blocks matched the monomer/initiator ratio. A structural switch element, which controls the hydrophilicity of the pentablock copolymers, was incorporated in the form of the p(l‐Glu) blocks. The pentablock copolymers became water soluble after hydrolyzing the benzyl ester protective groups. The pentablock copolymers self‐assembled into polymeric aggregates ranging in size between 160 and 340 nm. Hydrogels formed readily if the central PEG block had a molecular weight of at least 4600 Da and the terminal A‐blocks consisted of p(l‐Leu). SEM images confirmed the size ranges of the polymeric aggregates and showed non‐distinct spherical aggregates. © 2016 Society of Chemical Industry
Reactive Liners Prepared Using Powders of Aluminum and Aluminum‐Magnesium Alloys
Authors: Guadarrama Jose , Dreizin Edward L. , Glumac Nick 
Published: May 2016

AbstractCylindrical reactive liners filled with powders of aluminum, aluminum‐magnesium alloys, and aluminum‐magnesium powder blends were prepared and initiated by a centrally located explosive charge. The experiments were performed in a cubic chamber. Several transient pressure measurements were taken in addition to the quasistatic pressure caused by the explosion. Results were compared against a reference case with an inert liner filled with aluminum oxide powder. For all reactive liners, an increase in both quasistatic pressure and blast wave strength were observed compared to the case of an inert liner. In experiments with mechanically alloyed Al⋅Mg powders, the quasistatic pressure is effectively the same as in experiments with pure aluminum. An improvement in the achieved quasistatic pressure is observed for the liners with a cast alloyed Al⋅Mg powder. Most interestingly, a substantial contribution to the air blast indicative of very early reaction occurring in sub‐millisecond time scale is observed for all experiments with reactive liners. The most substantial improvement in the blast characteristics is observed in experiments with mechanically alloyed Al⋅Mg powders. While the mechanisms of prompt reactions of metals and alloys remain largely unexplored, the present results highlight the importance of such reactions for reactive liners and other components of energetic systems.
Studies of human pancreatic elastase treatment of rabbit and human vein rings to predict human therapeutic doses
Authors: Burke Steven K. , Bunton David , Bingham Karen , Moss Emma , Bland Kimberly S. , Starcher Barry , Wong Marco D. , Franano F. Nicholas 
Published: May 2016

AbstractVascular tissue contains abundant elastic fibers that contribute to vessel elasticity. Vonapanitase (formerly PRT‐201) is a recombinant human chymotrypsin‐like elastase family member 1 (CELA1) shown to cleave the elastin component of elastic fibers, resulting in increased vessel diameter. The purpose of these current studies was to determine vein diameter, wall thickness, elastin content, and vonapanitase potency in veins used in a model of arteriovenous fistula (AVF) and in patients undergoing AVF creation for hemodialysis access to guide dose selection for human trials. Rabbit linguofacial, maxillary, and external jugular veins, and human basilic and upper and lower arm cephalic veins were dissected postmortem and sectioned into 2 mm length rings. Rings were incubated in vonapanitase at 37°C at varying concentrations and times. Elastin content was estimated histologically and by quantifying desmosine, a protein cross‐link unique to elastin. Rabbit veins were substantially thinner and contained less elastin than human veins. In human veins, elastin content was greatest in basilic and least in lower arm cephalic. Vonapanitase removed elastin in a time‐ and concentration‐dependent manner in all vein types. A lower concentration of vonapanitase was required to remove elastin from rabbit relative to human veins. In summary, vonapanitase reduced the elastin content of rabbit and human veins but did so at a lower concentration in the rabbit veins. Rabbit models may overestimate the potency of vonapanitase in humans. These results indicate that human dose selection should be guided by human vein ring experiments.
Induction of auxetic response in needle‐punched nonwovens: Effects of temperature, pressure, and time
Authors: Verma Prateek , Shofner Meisha L. , Lin Angela , Wagner Karla B. , Griffin Anselm C. 
Published: May 2016

We have examined the effect of temperature, pressure, and time on the magnitude of induced auxetic response in post‐manufacture‐processed needle‐punched nonwovens. Different combinations of these processing parameters – temperatures ranging from room temperature to above the glass transition temperature (Tg) of constituent fibers, pressure of 0.49 or 2.45 MPa, and duration of 4 or 24 h – were used to process these nonwovens. This resulted in some permanent compression (defined as “compression set”) and in out‐of‐plane auxetic behavior of the fabric, both of which were found to be proportional to the severity of the processing conditions employed. Milder processing conditions were found to be insufficient in producing significant compression set and hence produced little or no auxetic response. Using micro‐CT and optical video microscopy techniques, it was found that the processing conditions caused the fiber bundles present in needle‐punched nonwovens to assume a buckled/tilted state, which opened up during mechanical extension and hence were instrumental in the observed thickness increase.Out‐of‐plane Poisson's ratio with strain for as‐received and treated nonwovens.
Crafting Creative Nonfiction: From Close Reading to Close Writing
Authors: Dollins Cynthia A. 
Published: May 2016

AbstractA process writing project in a third‐grade classroom explored the idea of using nonfiction mentor texts to assist students in writing their own creative informational texts about animals. By looking at author craft and structure during close reading activities with nonfiction Twin Texts, students were taught how to emulate these techniques in their own writing. A process for implementation of the project is presented here. The project included mini‐lessons on various aspects of writing improvement such as crafting strong leads, using specific revision strategies, and exploring narrative elements in some informational texts. The results suggest that students were able to replicate writing style strategies found in mentor texts. Final writing drafts displayed how students included important facts in their informational writing and presented these facts in an engaging and powerful way.
A Comprehensive Study on the Synthesis and Micellization of Disymmetric Gemini Imidazolium Surfactants
Authors: Zhao Xiaohui , An Dong , Ye Zhiwen 
Published: May 2016

AbstractTwo groups of disymmetric Gemini imidazolium surfactants, [C14C4Cmim]Br2 (m = 10, 12, 14) and [CmC4Cnim]Br2 (m + n = 24, m = 12, 14, 16, 18) surfactants, were synthesized and their structures were confirmed by 1H NMR and ESI–MS spectroscopy. Their adsorption at the air/water interface, thermodynamic parameters and aggregation behavior were explored by means of surface tension, electrical conductivity and steady‐state fluorescence. A series of surface activity parameters, including cmc, γcmc, πcmc, pC20, cmc/C20, Γmax and Amin, were obtained from surface tension measurements. The results revealed that the overall hydrophobic chain length (Nc) for [C14C4Cmim]Br2 and the disymmetry (m/n) for [CmC4Cnim]Br2 had a significant effect on the surface activity. The cmc values decreased with an increase of Nc or m/n. The thermodynamic parameters of micellization (ΔGmθ, ΔHmθ, ΔSmθ) derived from the electrical conductivity indicated that the micellization process of [C14C4Cmim]Br2 and [CmC4Cnim]Br2 was entropy‐driven at different temperatures, but the contribution of ΔHmθ to ΔGmθ was enhanced by increasing Nc or m/n. The micropolarity and micellar aggregation number (Nagg) were estimated by steady‐state fluorescence measurements. The results showed that the surfactant with higher Nc or m/n can form larger micelles, due to a tighter micellar structure.
Neural effects of social environmental stress – an activation likelihood estimation meta-analysis
Authors: Mothersill O. , Donohoe G. 
Published: May 2016

BackgroundSocial environmental stress, including childhood abuse and deprivation, is associated with increased rates of psychiatric disorders such as schizophrenia and depression. However, the neural mechanisms mediating risk are not completely understood. Functional magnetic resonance imaging (MRI) studies have reported effects of social environmental stress on a variety of brain regions, but interpretation of results is complicated by the variety of environmental risk factors examined and different methods employed.MethodWe examined brain regions consistently showing differences in blood oxygen level-dependent (BOLD) response in individuals exposed to higher levels of environmental stress by performing a coordinate-based meta-analysis on 54 functional MRI studies using activation likelihood estimation (ALE), including an overall sample of 3044 participants. We performed separate ALE analyses on studies examining adults (mean age ⩾18 years) and children/adolescents (mean age <18 years) and a contrast analysis comparing the two types of study.ResultsAcross both adult and children/adolescent studies, ALE meta-analysis revealed several clusters in which differences in BOLD response were associated with social environmental stress across multiple studies. These clusters incorporated several brain regions, among which the right amygdala was most frequently implicated.ConclusionsThese findings suggest that a variety of social environmental stressors is associated with differences in the BOLD response of specific brain regions such as the right amygdala in both children/adolescents and adults. What remains unknown is whether these environmental stressors have differential effects on treatment response in these brain regions.
Support networks of childless older people: informal and formal support in Europe
Authors: DEINDL CHRISTIAN , BRANDT MARTINA 
Published: May 2016

ABSTRACTWestern societies are ageing rapidly. Today people do not only live longer, they also have fewer children. These developments exert considerable pressure on welfare states. Children have usually been the mainstay of old age support, especially when there is no partner. We thus face new challenges: On which support networks can a growing number of childless older people rely? (How) can the lack of children be compensated in the informal social network? What role does the state play and how is informal and formal support linked? Our comparative analyses of the support networks of childless elders are based on the first two waves of the Survey of Health, Ageing and Retirement in Europe, including 14,394 people with (instrumental) activities of daily living limitations aged 50 and over from 12 European countries. On average, 10 per cent of older Europeans today have no children. Sporadic informal support for these elders is often taken over by the extended family, friends and neighbours, and thus the lack of children is compensated within the social network. Intense care tasks, however, are more likely provided by professional providers, especially in the case of childless older people. In countries with low social service provision, childless elders are therefore likely to experience a lack of (formal) support, especially when depending on vital care.
A flexible three-dimensional electrode mesh: An enabling technology for wireless brain–computer interface prostheses
Authors: Xiang Zhuolin , Liu Jingquan , Lee Chengkuo 
Published: May 2016

AbstractThe neural interface is a key component in wireless brain–computer prostheses. In this study, we demonstrate that a unique three-dimensional (3D) microneedle electrode on a flexible mesh substrate, which can be fabricated without complicated micromachining techniques, is conformal to the tissues with minimal invasiveness. Furthermore, we demonstrate that it can be applied to different functional layers in the nervous system without length limitation. The microneedle electrode is fabricated using drawing lithography technology from biocompatible materials. In this approach, the profile of a 3D microneedle electrode array is determined by the design of a two-dimensional (2D) pattern on the mask, which can be used to access different functional layers in different locations of the brain. Due to the sufficient stiffness of the electrode and the excellent flexibility of the mesh substrate, the electrode can penetrate into the tissue with its bottom layer fully conformal to the curved brain surface. Then, the exposed contact at the end of the microneedle electrode can successfully acquire neural signals from the brain.