bluuebunny/crossref_metadata_2025 huggingface dataset:
Out‐of‐plane stability of buckling‐restrained braces including moment transfer capacity
Authors: Takeuchi Toru , Ozaki Hitoshi , Matsui Ryota , Sutcu Fatih
Published: April 2014

Buckling‐restrained braces (BRBs) are widely used as ductile seismic‐resistant and energy‐dissipating structural members in seismic regions. Although BRBs are expected to exhibit stable hysteresis under cyclic axial loading, one of the key limit states is global flexural buckling, which can produce an undesirable response. Many prior studies have indicated the possibility of global buckling of a BRB before its core yields owing to connection failure. In this paper, BRB stability concepts are presented, including their bending‐moment transfer capacity at restrainer ends for various connection stiffness values with initial out‐of‐plane drifts, and a unified simple equation set for ensuring BRB stability is proposed. Moreover, a series of cyclic loading tests with initial out‐of‐plane drifts are conducted, and the results are compared with those of the proposed equations. © 2013 The Authors.Earthquake Engineering & Structural Dynamicspublished by John Wiley & Sons Ltd.
Strong motion displacement waveforms using 10‐Hz precise point positioning GPS: an assessment based on free oscillation experiments
Authors: Moschas Fanis , Avallone Antonio , Saltogianni Vasso , Stiros Stathis C.
Published: April 2014

The recently developed precise point positioning (PPP) technique permits to compute instantaneous coordinates of a GPS station relatively to distant reference stations and waveforms of ground displacements during strong motions at the 1 Hz level. This is another application of GPS, different from the computation of static coseismic movements or of accurate monitoring of dynamic displacements of structures using a static receiver and a nearby moving receiver (DGPS). Recently, earthquake ground displacement waveforms using 10‐Hz GPS data have also been calculated, but no independent evidence to assess their quality exists. To overcome this problem, we evaluated the output of 10‐Hz PPP results on the basis of supervised learning experiments. Semistatic and dynamic displacements (damped harmonic oscillations) of known characteristics of the order of a few centimeter were produced and were recorded by GPS, an accelerometer, and a robotic total station. Time series of instantaneous displacements were analyzed using different PPP techniques and were compared with reference (true) values derived from DGPS and the other sensors. Our analysis revealed that the PPP‐derived coordinates are contaminated by long‐period noise but they can display the details of semistatic displacements, while their short‐period component describes well the pattern of waveforms and spectra (at least up to 4 Hz) of dynamic displacements, with up to 20 mm accuracy for isolated points. These results indicate that 10‐Hz PPP‐GPS is useful for earthquake engineering and can safely be used to reconstruct waveforms of deflections of the ground and of various points on structures during strong motions. Copyright © 2014 John Wiley & Sons, Ltd.
Comparison of electronic and mechanical Schmidt hammers in the context of exposure‐age dating: are Q‐ and R‐values interconvertible?
Authors: Winkler Stefan , Matthews John A.
Published: April 2014

Application of Schmidt‐hammer exposure‐age dating (SHD) to landforms has substantially increased in recent years. The original mechanical Schmidt hammer records R‐(rebound) values. Although the newly introduced electronic Schmidt hammer (SilverSchmidt) facilitates greatly improved data processing, it measures surface hardness differently, recording Q‐(velocity) values that are not a priori interconvertible with R‐values. This study is the first to compare the performance of both instruments in the context of field‐based exposure‐age dating with a particular focus on the interconvertibility of R‐values and Q‐values. The study was conducted on glacially polished pyroxene‐granulite gneiss, Jotunheimen, southern Norway. Results indicate that mean Q‐values are consistently 8–10 units higher than mean R‐values over the range of values normally encountered in the application of SHD to glacial and periglacial landforms. A convenient conversion factor of ±10 units may, therefore, be appropriate for all but the softest rock types close to the technical resolution of the instruments. The electronic Schmidt hammer should therefore be regarded as a useful complement and potential replacement for the mechanical Schmidt hammer. Conversion of published R‐values data to Q‐values requires, however, careful control and documentation of instrument calibration. Copyright © 2014 John Wiley & Sons, Ltd.
Ecological factors contributing to variability of persistent organic pollutant bioaccumulation within forage fish communities of the Detroit River, Ontario, Canada
Authors: McLeod Anne M. , Paterson Gord , Drouillard Ken G. , Haffner G. Douglas
Published: April 2014

Understanding variability of contaminant bioaccumulation within and among fish populations is critical for distinguishing between the chemical and biological mechanisms that contribute to food web biomagnification and quantifying contaminant exposure risks in aquatic ecosystems. The present study examined the relative contributions of chemical hydrophobicity (octanol–water partition coefficient [KOW]) and habitat use as factors regulating variability in polychlorinated biphenyl (PCB) congener bioaccumulation in 3 lower trophic level cyprinid species across spatial and temporal scales. Bluntnose minnows (Pimephales notatus), spottail shiners (Notropis hudsonius), and emerald shiners (Notropis atherinoides) were sampled at 3 locations in the Detroit River, Ontario, Canada. Variability in PCB concentration was evaluated with respect to several factors, including chemical hydrophobicity, site, season, species, and weight using sum of squares and Levene's test of homogeneity of variance. Individual variability in bioaccumulated congener-specific residues depended on chemical hydrophobicity with mid- and high-range KOW congeners (log KOW > 6.0), demonstrating the highest amount of variance compared with low KOW congeners. Different feeding strategies also contributed to the variance observed for mid-range KOW congeners among species. In the present study, benthic feeding specialists exhibited lower variance in PCB concentrations compared with the 2 generalist species. The results indicate that chemical hydrophobicity and feeding ecology not only contribute to differences in the biomagnification potentials of fish, but also regulate between-individual variation in PCB concentrations both across and within fish species. Environ Toxicol Chem 2014;33:1825–1831. © 2014 SETAC
Self organising cloud cells: a resource efficient network densification strategy
Authors: Alsedairy Talal , Qi Yinan , Imran Ali , Imran Muhammad Ali , Evans Barry
Published: April 2014

Network densification is envisioned as the key enabler for 2020 vision that requires cellular systems to grow in capacity by hundreds of times to cope with unprecedented traffic growth trends being witnessed since advent of broadband on the move. However, increased energy consumption and complex mobility management associated with network densifications remain as the two main challenges to be addressed before further network densification can be exploited on a wide scale. In the wake of these challenges, this paper proposes and evaluates a novel dense network deployment strategy for increasing the capacity of future cellular systems without sacrificing energy efficiency and compromising mobility performance. Our deployment architecture consists of smart small cells, called cloud nodes, which provide data coverage to individual users on a demand bases while taking into account the spatial and temporal dynamics of user mobility and traffic. The decision to activate the cloud nodes, such that certain performance objectives at system level are targeted, is carried out by the overlaying macrocell based on a fuzzy‐logic framework. We also compare the proposed architecture with conventional macrocell only deployment and pure microcell‐based dense deployment in terms of blocking probability, handover probability and energy efficiency and discuss and quantify the trade‐offs therein.© 2014 The Authors. Transactions on Emerging Telecommunications Technologies published by John Wiley & Sons, Ltd.
A decision theoretic approach for clustering and rate allocation in coordinated multi‐point (CoMP) networks with delayed channel state information
Authors: Cai Yegui , Yu F. Richard , Bu Shengrong
Published: April 2014

Coordinated multi‐point (CoMP) is a promising technique in next generation cellular networks. Compared with traditional mobile networks, one of the important design problems in CoMP is clustering, which decides how the base stations cooperate with each other. Channel state information (CSI) is needed in clustering decisions in CoMP. Most previous works assume that perfect CSI is available. However, practical systems suffer from constraints imposed by backhaul networks, which are used for CSI exchange. In this paper, we study the clustering and rate allocation problem in CoMP with delayed CSI. We present a decision theoretic approach to this problem. Specifically, we model such a system in the framework of networked Markov decision process (networked‐MDP) with delays, which is equivalent to a partial observable Markov decision process (POMDP). We derive an optimal policy for such POMDP with low computation complexity. Simulation results are provided to show promising gain achieved in the proposed scheme over existing schemes especially when the delay is large and the channel coherence time is small. Copyright © 2014 John Wiley & Sons, Ltd.
Spectral gamma‐ray logs and palaeoclimate change? Permian–Triassic, Persian Gulf
Authors: Ghasemi‐Nejad Ebrahim , Ruffell Alastair , Rahimpour‐Bonab Hossein , Sharifi Mohammed , Soltani Behzad , Sfidari Ebrahim
Published: April 2014

Spectral gamma ray (SGR) logs are used as stratigraphic tools in correlation, sequence stratigraphy and most recently, in clastic successions as a proxy for changes in hinterland palaeoweathering. In this study we analyse the spectral gamma ray signal recorded in two boreholes that penetrated the carbonate and evaporate‐dominated Permian–Triassic boundary (PTB) in the South Pars Gasfield (offshore Iran, Persian Gulf) in an attempt to analyse palaeoenvironmental changes from the upper Permian (Upper Dalan Formation) and lower Triassic (Lower Kangan Formation). The results are compared to lithological changes, total organic carbon (TOC) contents and published stable isotope (δ18O,δ13C) results. This work is the first to consider palaeoclimatic effects on SGR logs from a carbonate/evaporate succession. While Th/U ratios compare well to isotope data (and thus a change to less arid hinterland climates from the Late Permian to the Early Triassic), Th/K ratios do not, suggesting a control not related to hinterland weathering. Furthermore, elevated Th/U ratios in the Early Triassic could reflect a global drawdown in U, rather than a more humid episode in the sediment hinterlands, with coincident changes in TOC. Previous work that used spectral gamma ray data in siliciclastic successions as a palaeoclimate proxy may not apply in carbonate/evaporate sedimentary rocks. Copyright © 2014 John Wiley & Sons, Ltd.
REALIZED BETA GARCH: A MULTIVARIATE GARCH MODEL WITH REALIZED MEASURES OF VOLATILITY
Authors: Hansen Peter Reinhard , Lunde Asger , Voev Valeri
Published: April 2014

We introduce a multivariate generalized autoregressive conditional heteroskedasticity (GARCH) model that incorporates realized measures of variances and covariances. Realized measures extract information about the current levels of volatilities and correlations from high‐frequency data, which is particularly useful for modeling financial returns during periods of rapid changes in the underlying covariance structure. When applied to market returns in conjunction with returns on an individual asset, the model yields a dynamic model specification of the conditional regression coefficient that is known as the beta. We apply the model to a large set of assets and find the conditional betas to be far more variable than usually found with rolling‐window regressions based exclusively on daily returns. In the empirical part of the paper, we examine the cross‐sectional as well as the time variation of the conditional beta series during the financial crises. Copyright © 2014 John Wiley & Sons, Ltd.
Optofluidic rotation of living cells for single‐cell tomography
Authors: Kolb Thorsten , Albert Sahradha , Haug Michael , Whyte Graeme
Published: April 2014

Flow cytometry provides a high throughput, multi‐dimensional analysis of cells flowing in suspension. In order to combine this feature with the ability to resolve detailed structures in 3D, we developed an optofluidic device that combines a microfluidic system with a dual beam trap. This allows for the rotation of single cells in a continuous flow, around an axis perpendicular to the imaging plane. The combination of both techniques enables the tomographic reconstruction of the 3D structure of the cell. In addition this method is capable to provide detailed 3D structural data for flow cytometry, as it improves the reconstructed z‐resolution of a standard microscopy system to produce images with isotropic resolution in all three axes.

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Preparation and Electrochemical Characterization of an Enzyme Electrode Based on Catalase Immobilized onto a Multiwall Carbon Nanotube‐Thionine Film
Authors: Hashemnia Sedigheh , Eskanari Mahbubeh
Published: April 2014

The present study was aimed at investigating the use of a mixture multiwall carbon nanotube (MWCNT) and thionine (Th) dye in designing of a thionine‐based electrochemical biosensor containing catalase (Ct) enzyme (MWCNT‐Nafion‐Th/Ct) onto a glassy carbon electrode (GCE). The effects of pH, MWCNT concentration and thionine concentration on electrochemical response were explored for optimum analytical performance. The modified electrode exhibited a pair of well‐defined, quasi‐reversible peaks at formal potential (Eo′) = ‐0.218 ± 0.017 V vs. Ag/AgCl corresponding to the Thox/Thred redox couples in the presence of MWCNT, Nafion, and Ct. The electrochemical parameters, including charge‐transfer coefficient (0.36), and apparent heterogeneous electron transfer rate constant (4.28 ± 0.26 s−1) were determined. Using differential pulse voltammetry, the prepared enzyme electrode exhibited a linear response to hydrogen peroxide (H2O2) in the range of 10.0‐100.0 μM with a detection limit 8.7 μM and a sensitivity of 6051.0 μA mM−1 cm−2.
Development of a Novel Hybrid Immobilization Material (HY‐IM) for Fermentative Biohydrogen Production from Beverage Wastewater
Authors: Sivagurunathan Periyasamy , Kumar Gopalakrishnan , Sen Biswarup , Lin Chiu‐Yue
Published: April 2014

A novel material (hybrid immobilization material, HY‐IM) was developed by the combination of calcium‐alginate, activated carbon (prepared from de‐oiled jatropha waste), wako gel (silica gel) and chitosan for immobilization of hydrogen‐producing bacteria. The stability of the prepared immobilized cells was evaluated by ten repetitive batch experimental runs; the cumulative hydrogen production from beverage wastewater during ten runs was in the range of 2865 to 3300 mL H2/L. The Scanning electron microscopy (SEM) images of the HY‐IM showed bacterial cells entrapment. The hydrogen production performance of the reactor with HY‐IM (1.12 ± 0.04 mol H2/mol hexoseutilized) was comparable to suspended cells reactor (1.07 ± 0.01 mol H2/mol hexoseutilized), and demonstrated repeated usage of same HY‐IM in the reactor with high stability. Experimental evidence suggests that HY‐IM can be applied in continuous biohydrogen production from industrial wastewaters with high efficiency and stability.
Partial ‐Parallelisms in Finite Projective Spaces
Authors: Etzion Tuvi
Published: April 2014

In this paper, we consider the following question. What is the maximum number of pairwise disjoint k‐spreads that exist in PG()? We prove that if divides and then there exist at least two disjoint k‐spreads in PG() and there exist at least pairwise disjoint k‐spreads in PG(n, 2). We also extend the known results on parallelism in a projective geometry from which the points of a given subspace were removed.
Mg2+‐Dependent Modulation of BKCa Channels by Genistein in Rat Arteriolar Smooth Muscle Cells
Authors: Wang Xiaoran , Zhao Tingting , Zhou Shanshan , Sun Lina , Zhang Liming , Yu Guichun
Published: April 2014

Genistein, a protein tyrosine kinase (PTK) inhibitor, regulates ion channel activities. However, the mechanism of action of genistein on large‐conductance calcium‐activated potassium (BKCa) channels is unclear. This study aimed to investigate whether the mechanism of Mg2+‐dependent modulation of BKCa channel activity in vascular smooth muscle cells involved inhibition of phosphorylation by genistein or direct interaction between genistein and BKCa channels. The whole‐cell and inside‐out patch‐clamp techniques were used to measure BKCa currents and the effects of genistein on BKCa channel activities in rat mesenteric arteriolar smooth muscle cells. We found that the effects of genistein on BKCa currents were Mg2+‐dependent. Genistein (50 μM) inhibited BKCa currents if the intracellular free magnesium concentration ([Mg2+]i) was 2 μM or 20 μM, but amplified BKCa currents if [Mg2+]i was 200 μM or 2000 μM. The inhibitory effect of genistein on BKCa currents was reversed by the protein tyrosine phosphatase inhibitor sodium orthovanadate (0.5 mM). Daidzein (50 μM), an inactive analogue of genistein, also amplified BKCa currents, and its amplification was insensitive to orthovanadate. Another PTK inhibitor, tyrphostin 23 (50 μM), reduced the open probability of BKCa channels. This inhibitory effect was weaker at 200 μM [Mg2+]i than at 2 μM [Mg2+]i, and was countered by orthovanadate. Our results suggest that genistein amplifies BKCa currents at a high [Mg2+]i, but inhibits BKCa currents at a low [Mg2+]i. The mechanism of this biphasic effects involves PTK‐independent amplification and [Mg2+]i‐PTK‐dependent inhibition. J. Cell. Physiol. 229: 1981–1989, 2014. © 2014 Wiley Periodicals, Inc.
Plasma and cerebrospinal fluid concentrations of ibuprofen in pediatric patients and antipyretic effect: Pharmacokinetic–pharmacodynamic modeling analysis
Authors: Har‐Even Ronly , Stepensky David , Britzi Malka , Soback Stefan , Chaim Adina Bar , Brandriss Norit , Goldman Michael , Berkovitch Matitiahu , Kozer Eran
Published: April 2014

We aimed to determine the relationship between plasma and cerebrospinal fluid (CSF) concentrations of ibuprofen and the antipyretic effect in pediatric patients. A prospective cohort of infants and children aged 3 months to 15 years and treated with ibuprofen was studied. The patients received ibuprofen (via oral route, median dose of 10.0 mg/kg; 3.4–11.4 mg/kg range), samples of blood and CSF were collected, and body temperature was measured. Sequential analysis of the pharmacokinetic and pharmacodynamic data from 28 patients was performed using a population modeling approach. The observed concentration versus time data indicated substantial pharmacokinetic variability in absorption and distribution of ibuprofen between the patients. The pharmacokinetic modeling outcomes indicate that following a ∼25‐minute lag time, ibuprofen is rapidly absorbed to the central compartment and rapidly equilibrates with the CSF, resulting in the total ibuprofen concentration in the CSF versus plasma (CCSF/Cplasma) of 0.011 ± 0.007. The antipyretic effect of ibuprofen was best described by an indirect response PK‐PD model incorporating patient baseline body temperature and ibuprofen concentration in the CSF. We conclude that the pharmacokinetic–pharmacodynamic modeling can be used to predict the time course of ibuprofen plasma and CSF concentrations and of the antipyretic effects in individual pediatric patients.
Person‐centric clinical trials: Ethical challenges in recruitment and data transparency for improved outcomes
Authors: Robbins Dennis A. , Curro Frederick A. , Mattison John
Published: April 2014

Practitioners participating in clinical studies are faced with a number of ethical issues related to recruitment, informed consent, handling and transparency of data. Practitioners educated in Good Clinical Practice, applying the philosophy of person‐centricity within a network utilizing risk‐based monitoring and remote data entry can provide the requisite infrastructure and oversight to support person‐centric clinical studies. While “patient‐centered” clinical studies allow for a broader clinical outcome perspective beyond the investigator, the person‐centric approach, accounts for the comprehensiveness and complexity of how we make health and healthcare decisions. Augmenting person centricity with comparative effectiveness studies allow for the inclusion of individual data significantly contributing to the aggregation of multiple data sets about individuals and populations. This enables more powerful and personal analytics and care and everyone is afforded the opportunity and privilege to contribute to improve clinical outcomes and in controlling and containing costs. Policy and institutional investment in infrastructure are prerequisite to accommodate these opportunities, to minimize abuses, and provide pathways for analyzing alternative healthcare patterns. Data provided will be comprehensive and robust, representative of use, with safety data more easily discernible from persons with a known past medical and health history.
Photochemical decoration of silver nanoparticles on ZnO nanowires as a three‐dimensional substrate for surface‐enhanced Raman scattering measurement
Authors: Satheeshkumar Elumalai , Yang Jyisy
Published: April 2014

To increase the sensitivity in surface‐enhanced Raman scattering (SERS) measurement, a three‐dimensional (3D) SERS substrate was prepared by the decoration of silver nanoparticles (AgNPs) on the side walls of ZnO nanowires. The prepared 3D SERS substrates provide the advantages of highly loaded density of AgNPs, with a large specific surface area to interact with analytes, and the ease for the analytes to access the surfaces of AgNPs. To prepare the substrates, ZnO nanowires were first grown on a glass plate by wet chemical method. By treating SnCl2 on the surfaces of ZnO nanowires, Ag seeds could be formed on the side wall of the ZnO nanowires, which were further grown to a suitable size for SERS measurements via photochemical reduction. To optimize and understand the influences of the parameters used in preparation of the substrates, the reaction conditions were systematically adjusted and examined. Results indicated that AgNPs could be successfully decorated on the side wall of the ZnO nanowires only by the assistances of SnCl2. The size and density of AgNPs were affected by both the concentration of silver nitrate and the irradiation time. With optimized condition, the prepared 3D substrates provided an enhancement factor approaching 7 orders of magnitude compared with conventional Raman intensity. Copyright © 2014 John Wiley & Sons, Ltd.
Three‐phase hollow fiber liquid‐phase microextraction based on a magnetofluid for the analysis of aristolochic acids in plasma by high‐performance liquid chromatography
Authors: Song Rui Juan , Pu Feng Ping , Zhou Jun , Sun Jiang Bing , Zeng Ping , Zhang Qiong
Published: April 2014

A new and fast sample preparation technique based on three‐phase hollow fiber liquid‐phase microextraction with a magnetofluid was developed and successfully used to quantify the aristolochic acid I (AA‐I) and AA‐II in plasma after oral administration of Caulis akebiae extract. Analysis was accomplished by reversed‐phase high‐performance liquid chromatography with fluorescence detection. Parameters that affect the hollow fiber liquid‐phase microextraction processes, such as the solvent type, pH of donor and acceptor phases, content of magnetofluid, salt content, stirring speed, hollow fiber length, extraction temperature, and extraction time, were investigated and optimized. Under the optimized conditions, the preconcentration factors for AA‐I and AA‐II were >627. The calibration curve for two AAs was linear in the range of 0.1–10 ng/mL with the correlation coefficients >0.9997. The intraday and interday precision was <5.71% and the LODs were 11 pg/mL for AA‐I and 13 pg/mL for AA‐II (S/N = 3). The separation and determination of the two AAs in plasma after oral administration of C. akebiae extract were completed by the validated method.
Using DNA to describe and quantify interspecific killing of fishers in California
Authors: Wengert Greta M. , Gabriel Mourad W. , Matthews Sean M. , Higley J. Mark , Sweitzer Rick A. , Thompson Craig M. , Purcell Kathryn L. , Barrett Reginald H. , Woods Leslie W. , Green Rebecca E. , Keller Stefan M. , Gaffney Patricia M. , Jones Megan , Sacks Benjamin N.
Published: April 2014

Interspecific killing is common among carnivores and can have population‐level effects on imperiled species. The fisher (Pekania [Martes] pennanti) is a rare forest carnivore in western North America and a candidate for listing under the United States Endangered Species Act. Interspecific killing and intraguild predation are poorly understood in fishers and potential threats to existing western populations. We studied the prevalence and patterns of interspecific killing of fishers in the southern Sierra Nevada and Coastal Range of California. We collected forensic evidence and samples from the carcasses and predation sites, conducted full necropsies when possible, and used molecular methods to determine species of predators responsible for killing fishers. We recovered 101 (59 female, 42 male) fisher carcasses; for 62 (61%) carcasses, we attributed cause of death to interspecific killing. We found that bobcats (Lynx rufus, n = 25 fisher mortalities), mountain lions (Puma concolor, n = 20), and coyotes (Canis latrans, n = 4) were predators of fishers in our study areas. Bobcats killed only female fishers, whereas mountain lions more frequently killed male than female fishers, confirming our hypothesis that female fishers would suffer lethal attacks by smaller predators than would male fishers. Coyotes rarely killed fishers. We found differences in pathologic characteristics of the predation events among the 3 predator species, which may be helpful in identifying predator species. © 2014 The Wildlife Society.
Targeting mitigation efforts: The role of speed limit and road edge clearance for deer–vehicle collisions
Authors: Meisingset Erling L. , Loe Leif E. , Brekkum Øystein , Mysterud Atle
Published: April 2014

Deer–vehicle collisions (DVCs) have major social, economic, and animal welfare costs. Modeling of accident risk relative to environmental characteristics could enable managers to plan the layout of new roads or determine optimal location of mitigation measures to reduce the number of accidents on existing roads. We analyzed position data providing road crossings from 67 global positioning system (GPS)‐marked red deer (Cervus elaphus) and location data of 271 car killed deer within the home ranges of the GPS‐marked red deer. We modeled collision risk as a function of speed limit, season, road characteristics, and habitat features. For a subset of the data, we tested if vegetation clearance along a highway reduced the collision frequency of red deer. The relative risk for DVCs increased with speed limit. We found a higher risk for DVCs during winter compared to the other seasons. Forest cover, distance to pasture, and terrain ruggedness substantially affected risk of DVCs. Road edge clearance reduced the frequency of DVCs, but the effect appeared in the winter season only with a decrease of 53%. Our study highlights that speed limit reduction and road edge clearance are both powerful mitigation tools to reduce the number of DVCs. © 2014 The Wildlife Society.
Carbon Life Cycle Assessment for Prairie as a Crop in Reclaimed Mine Land
Authors: Guzman Jose G. , Lal Rattan , Byrd Shana , Apfelbaum Steven I. , Thompson Ry. L.
Published: April 2014

A life cycle assessment with carbon (C) as the reference unit was used to balance the benefits of land preparation practices of establishing tall‐grass prairies as a crop for reclaimed mine land with reduced environmental damage. Land preparation and management practices included disking with sub‐soiling (DK‐S), disking only (DK), no tillage (NT), and no tillage with grazing (NT‐G). To evaluate the C balance and energy use of each of the land preparations, an index of sustainability (Is = CO/CI, Where: CO is the sum of all outputs and CI is the sum of all inputs) was used to assess temporal changes in C.

Of the four land preparation and management practices, DK had the highest Is at 8·53. This was due to it having the least degradation of soil organic carbon (SOC) during land‐use change (−730 kg ha−1 y−1) and second highest aboveground biomass production (9,881 kg ha−1). The highest aboveground biomass production occurred with NT (11,130 kg ha−1), although SOC losses were similar to DK‐S, which on average was 2,899 kg ha−1 y−1. The Is values for NT and DK‐S were 2·50 and 1·44, respectively. Grazing from bison reduced the aboveground biomass to 8,971 kg ha−1 compared with NT with no grazing, although stocking density was low enough that Is was still 1·94. This study has shown that converting from cool‐season forage grasses to tall‐grass prairie results in a significant net sink for atmospheric CO2 3 years after establishment in reclaimed mine land, because of high biomass yields compensating for SOC losses from land‐use change. Copyright © 2014 John Wiley & Sons, Ltd.
Intumescent Nanocoating Extinguishes Flame on Fabric Using Aqueous Polyelectrolyte Complex Deposited in Single Step
Authors: Cain Amanda A. , Murray Shannon , Holder Kevin M. , Nolen Craig R. , Grunlan Jaime C.
Published: April 2014

In an effort to produce a more effective and environmentally friendly flame‐retardant (FR) treatment for cotton fabric, a two‐ingredient aqueous polyelectrolyte complex was used to create a one‐step deposition system. This easy‐to‐apply nanocoating, made with nitrogen‐rich and phosphorous‐rich polyelectrolytes, maintains the fabric's weave structure by spontaneously coating individual fibers. Coating pick‐up is reproducible and is a function of both soak time and pot life of the polyelectrolyte complex. From microscale calorimetry data, cotton fabric soaked for only 1min in this “OnePot” flame‐retarding complex exhibits a 52.7% reduction in total heat release, with only 2.3 wt% coating added.
De novo mutation in the GNAL gene causing seemingly sporadic dystonia in a Serbian patient
Authors: Dobričić Valerija , Kresojević Nikola , Westenberger Ana , Svetel Marina , Tomić Aleksandra , Ralić Vesna , Petrović Igor , Lukić Milica Ječmenica , Lohmann Katja , Novaković Ivana , Klein Christine , Kostić Vladimir S.
Published: April 2014

Background

Mutations in GNAL (DYT25) have recently been established as the first confirmed cause of focal or segmental adult‐onset dystonia. Mutation carriers show craniocervical involvement; however, the GNAL mutational and phenotypic spectrum remain to be further characterized, and guidelines for diagnostic testing need to be established.

Methods

The authors used Sanger sequencing to test for changes in the GNAL coding or splice‐site regions in 236 Serbian patients suffering from isolated dystonia with craniocervical involvement.

Results

One novel likely pathogenic substitution (c.1061T>C; p.Val354Ala) in GNAL was detected in a sporadic cervical dystonia patient (mutation frequency: 0.4%). This mutation was not present in the DNA of either parent, despite confirmed parentage.

Conclusions

This is the first report of a de novo GNAL mutation causing genetically proven, seemingly sporadic DYT25 dystonia. Our finding highlights the importance of genetic testing for GNAL mutations in establishing the molecular diagnosis even for patients with a negative family history. © 2014 International Parkinson and Movement Disorder Society © 2014 International Parkinson and Movement Disorder Society
Solid‐state NMR studies of intermolecular interactions in solid polymer blends
Authors: Mirau Peter A. , White Jeffery L.
Published: April 2014

Most binary mixtures of polymers are not miscible on the molecular level in the absence of specific intermolecular interactions. Solid‐state 13C and 2D 13C, 1H NMR has been used to study miscible polymer blends in an attempt to identify the interacting groups and gain a molecular level understanding of the forces that drive irascibility. Selective polarization transfer methods, either solid‐state nuclear Overhauser effects or windowless isotropic mixing, were used to study these interactions, and the interacting groups in several strongly and weakly interacting polymer blends were identified.
Selective excitation SASS 13C NMR study of the phenylene motion of glassy polymers
Authors: Horii Fumitaka , Beppu Takayuki , Takaesu Noboru , Ishida Masato
Published: April 2014

Natural abundance 13C chemical shift anisotropy (CSA) spectra of the aromatic CH carbons of bisphenol‐A (BPA) residues were measured for BPA polycarbonate (BPAPC) and polyarylate (PAr) films at different temperatures by selective excitation switching angle sample spinning (SESASS) NMR spectroscopy. The CSA spectra thus obtained were analysed in terms of the two‐site exchange model for the flip motion of the phenylene group. In BPAPC, wide distributions in flip angle around 0° and 180° are well revealed under the situation of the first exchange limit for the flip motion and the widths become significantly broader with increasing temperature. These results are in good agreement with those of the previous 2H NMR analyses. Similar wide distributions in flip angle are also recognized even at lower temperatures for PAr, which is a non‐crystalline polymer composed of BPA and phthalic acid residues, suggesting more enhanced phenylene motion in this polymer. Moreover, the CSA spectra obtained for PAr above 60°C are found not to be reproduced by using the simple two‐site exchange model primarily based on the flip motions around 0° and 180°, probably owing to the onset of larger scale random motion of the flip axis.
Solid‐state 31P NMR characterization of bifunctional ion‐exchange resins
Authors: Crick Darrell W. , Alexandratos Spiro D.
Published: April 2014

NMR was used to provide evidence of site—site interactions in bifunctional polymers. A series of polymer‐supported phosphonic acid and phosphonate ester ligands was examined by solid‐state 31P NMR spectroscopy. Interaction between phosphonate monoethyl ester sites was demonstrated and disruption of this interaction by the addition of diethyl ester groups was shown. The effect of the synthesis conditions on the bifunctionality of resins containing both phosphonic acid and quaternary amine groups was examined. The spectra indicated that the phosphonic acid groups exists as phosphonate ions in the bifunctional amine/acid polymers and are capable of displacing chloride as the counterion on the amine sites.
Phase structure and polymorphism of highly syndiotactic polypropylene
Authors: Sozzani Piero , Simonutti Roberto , Comotti Angiolina
Published: April 2014

Polymorphs of highly syndiotactic polypropylene were studied by magic angle spinning 13C NMR. The conversion of one crystalline form into another was observed by the formation of different conformers of the polymer chain. The reversion of the metastable forms to the conventional crystalline phase was followed directly by variable‐temperature experiments and the addition of plasticizers. The multiplicity of signals associated with these structures were fully assigned in terms of trans,gauche conformations, by taking into account a sequence of four bonds in the main chain. Additional signals due to the packing of helical chains of opposite chirality are discussed in terms of the packing disorder present in the structure. The spectral pattern due to the amorphous region depends on temperature and thermal history, because the chain sequences can be observed under conditions of static and dynamic disorder as compared with the NMR time‐scale. The chains are fairly elongated, because they contain a considerable amount of trans sequences. Phase distribution and interfaces were characterized by hydrogen relaxation times in the rotating frame T1pH. Phase specificity was retained by recovering the magnetization on the 13C nucleus under high‐resolution conditions. Apparently spin diffusion cannot average out the T1pH value over the whole material when the thickness of the crystalline lemellae is increased by the annealing treatment. In the stretched material crystalline and amorphous phases are intimate and the chains in the amorphous phase also appear to be partly extended.
Domain structure and dynamic heterogeneities of a polyethylene acid ionomer by two‐dimensional solid‐state NMR
Authors: Chin Y.‐H. , Kaplan S.
Published: April 2014

Two‐dimensional wideline separation (WISE) NMR spectroscopy was employed to investigate the microscopic domain structure of an ethylene‐containing acid ionomer, poly(ethylene‐co‐methacrylic acid). Crystallinities were determined from deconvolution of the proton dimension lineshapes, and domain sizes were computed from proton spin diffusion behavior. The time‐scale for spin diffusion between the acid groups and the amorphous regions is less than 1 ms, because the methacrylic acid groups are situated in the amorphous domains. On the other hand, communication between amorphous and crystalline domains requires several milliseconds, consistent with crystalline domain sizes of ca 4 nm. The presence of intermolecular hydrogen‐bonded cross‐linking is clearly detected by the broad proton linewidth associated with the rigid methacrylic acid groups. It is shown that imbibed hexadecane, which strongly plasticizes the amorphous regions of the copolymer, has little effect on crystallinity, crystalline domain sizes or cross‐link sites.
Exchange kinetics by inversion transfer: Integrated analysis of the phosphorus metabolite kinetic exchanges in resting human skeletal muscle at 7 T
Authors: Ren Jimin , Yang Baolian , Sherry A. Dean , Malloy Craig R.
Published: April 2014

Purpose

To develop an inversion pulse‐based, chemical exchange saturation transfer‐like method for detection of 31P magnetization exchanges among all nuclear magnetic resonance visible metabolites suitable for providing an integrated kinetic analysis of phosphorus exchange reactions in vivo.

Methods

The exchange kinetics by inversion transfer (EKIT) sequence includes application of a frequency‐selective inversion pulse arrayed over the range of relevant 31P frequencies, followed by a constant delay and a hard readout pulse. A series of EKIT spectra, each given by a plot of Z‐magnetization for each metabolite of interest versus frequency of the inversion pulse, can be generated from this single data set.

Results

EKIT spectra reflect chemical exchange due to known biochemical reactions, cross‐relaxation effects, and relayed magnetization transfers due to both processes. The rate constants derived from EKIT data collected on resting human skeletal muscle were: ATP synthesis via ATP synthase (0.050 ± 0.016 s−1), ATP synthesis via creatine kinase (0.264 ± 0.023 s−1), and cross‐relaxation between neighboring spin pairs within ATP (0.164 ± 0.022 s−1).

Conclusion

EKIT provides a simple, alternative method to detect chemical exchange, cross relaxation, and relayed magnetization transfer effects in human skeletal muscle at 7 T. Magn Reson Med 73:1359–1369, 2015. © 2014 Wiley Periodicals, Inc.
The functional diversity of protein lysine methylation
Authors: Lanouette Sylvain , Mongeon Vanessa , Figeys Daniel , Couture Jean‐François
Published: April 2014

Large‐scale characterization of post‐translational modifications (PTMs), such as phosphorylation, acetylation and ubiquitination, has highlighted their importance in the regulation of a myriad of signaling events. While high‐throughput technologies have tremendously helped cataloguing the proteins modified by these PTMs, the identification of lysine‐methylated proteins, a PTM involving the transfer of one, two or three methyl groups to the ε‐amine of a lysine side chain, has lagged behind. While the initial findings were focused on the methylation of histone proteins, several studies have recently identified novel non‐histone lysine‐methylated proteins. This review provides a compilation of all lysine methylation sites reported to date. We also present key examples showing the impact of lysine methylation and discuss the circuitries wired by this important PTM.
Low‐cost and high‐performance: VoIP monitoring and full‐data retention at multi‐Gb/s rates using commodity hardware
Authors: García‐Dorado José Luis , Santiago del Río Pedro M. , Ramos Javier , Muelas David , Moreno Victor , López de Vergara Jorge E. , Aracil Javier
Published: April 2014

Voice over IP (VoIP) is increasingly replacing the old public switched telephone network (PSTN) technology. In this new scenario, there are several challenges for VoIP providers. First, VoIP requires a detailed monitoring of both users' quality of service (QoS) and experience (QoE) to a greater extent than in traditional PSTNs. Second, such a monitoring process must be able to track VoIP traffic in high‐speed networks, nowadays typically of multi‐Gb/s rates. Third, recent government directives require that providers retain information from their users' calls. Similarly, the convergence of data and voice services allows operators to provide new services such as full‐data retention, in which users' calls can be recorded for either quality assessment (call centers, QoE) or security purposes (lawful interception). This implies a significant investment in infrastructure, especially in large‐scale networks which require multiple points of measurement and redundancy. This paper proposes a novel methodology, architecture and system to fulfill such challenges, called VoIPCallMon, as well as the data structures and necessary hardware‐tuning knowledge for its development. As distinguishing features, VoIPCallMon provides very high performance, being able to process VoIP traffic on‐the‐fly at high bitrates, novel services and significant cost reduction by using commodity hardware with minimal interference with operational VoIP networks. The performance evaluation shows that the system copes with the VoIP load of real‐world operators. We further evaluated the system performance at a fully saturated 10 Gb/s link and no packet loss was reported, therefore demonstrating the potential of commodity hardware solutions. Copyright © 2014 John Wiley & Sons, Ltd.
A computational framework for dynamic data‐driven material damage control, based on Bayesian inference and model selection
Authors: Prudencio E. E. , Bauman P. T. , Faghihi D. , Ravi‐Chandar K. , Oden J. T.
Published: April 2014

In the present study, a general dynamic data‐driven application system (DDDAS) is developed for real‐time monitoring of damage in composite materials using methods and models that account for uncertainty in experimental data, model parameters, and in the selection of the model itself. The methodology involves (i) data data from uniaxial tensile experiments conducted on a composite material; (ii) continuum damage mechanics based material constitutive models; (iii) a Bayesian framework for uncertainty quantification, calibration, validation, and selection of models; and (iv) general Bayesian filtering, as well as Kalman and extended Kalman filters. A software infrastructure is developed and implemented in order to integrate the various parts of the DDDAS. The outcomes of computational analyses using the experimental data prove the feasibility of the Bayesian‐based methods for model calibration, validation, and selection. Moreover, using such DDDAS infrastructure for real‐time monitoring of the damage and degradation in materials results in results in an improved prediction of failure in the system. Copyright © 2014 John Wiley & Sons, Ltd.
The study of P19 stem cell behavior on aligned oriented electrospun poly(lactic‐co‐glycolic acid) nano‐fibers for neural tissue engineering
Authors: Irani Shiva , Zandi Mojgan , Salamian Najmeh , Saeed Seyed Mahdi , Daliri Joupari Morteza , Atyabi Seyed Mohammad
Published: April 2014

Recent medical cell therapy using polymeric biomaterial‐loaded stem cells with the capability of differentiation to specific neural population has directed focuses toward the recovery of central nervous system. Definite culture conditions that regulate cell morphogenesis, proliferation, survival, and differentiation to lineage specific cells have a great influence on the cells' life. In this research, random and aligned poly(lactic‐co‐glycolic acid) fibrous scaffolds with nano‐structure were prepared, and the effect of nano‐fiber morphology on the pluripotent P19 embryonic carcinoma cell proliferation and neural differentiation in response to retinoic acid induction was studied. Fiber morphology was assessed by scanning electron microscope (SEM). For in vitro studies, SEM, (4,5‐dimethylazol‐2‐yl)‐2,5‐diphenyl‐2H tetrazolium bromide assay, and immunofluorescent staining were carried out for the assessment of biological properties of the seeded cells. Our results showed that, because of their similarity with natural extracellular matrix, the aligned fibrous substrates provide the suitable surface for cell function as well as the augmentation of cell differentiation. Copyright © 2014 John Wiley & Sons, Ltd.
Preparation and luminescence properties of YAG:Ce phosphor for white LED application via a vacuum sintering method
Authors: Shi Hongling , Chen Jian , Huang Jiquan , Hu Qianqian , Deng Zhonghua , Cao Yongge , Yuan Xuanyi
Published: April 2014

YAG:Ce phosphors are synthesized by the vacuum sintering method, and their crystal structure, luminescence properties, and X‐ray photoelectron spectroscopy are discussed. The synthesized temperature of pure YAG phase is reduced by vacuum sintering. As‐synthesized YAG:Ce phosphors show a smaller average size of about 1 μm due to the fine starting materials, low sintering temperature, and the absence of flux. It is found that samples synthesized by the vacuum sintering method show stronger emission intensity and higher optimized Ce3+‐doping concentration. In addition, white light‐emitting diodes (LEDs) with improved color‐rendering properties are obtained by using modified Pr3+‐doped YAG:Ce phosphors.
Adjusting for misclassification in a stratified biomarker clinical trial
Authors: Liu Chunling , Liu Aiyi , Hu Jiang , Yuan Vivian , Halabi Susan
Published: April 2014

Clinical trials utilizing predictive biomarkers have become a research focus in personalized medicine. We investigate the effects of biomarker misclassification on the design and analysis of stratified biomarker clinical trials. For a variety of inference problems including marker–treatment interaction in particular, we show that marker misclassification may have profound adverse effects on the coverage of confidence intervals, power of the tests, and required sample sizes. For each inferential problem, we propose methods to adjust for the classification errors. Copyright © 2014 John Wiley & Sons, Ltd.