bluuebunny/crossref_metadata_2025 huggingface dataset:
Using stable isotopes to trace diet‐induced shifts in pathways of lipid metabolism
Authors: Pu Shuaihua , Yang Haifeng , Jones Peter J.H.
Published: March 2013

Advances in the use of stable isotopes in tracer methodology have clearly improved our capacity to investigate in vivo lipid metabolism in humans. The introduction of the isotope ratio mass spectrometry (IRMS) provides higher precision of measurement of isotopic enrichment to track shifts in diet on the flux of tracers through metabolic pathways. Novel applications using stable isotopes including 2H, 13C, and 18O have allowed important discoveries to be made in areas of fat and cholesterol metabolism in ways that have assisted in understanding diet‐disease relationships.
Graphene Enhances the Shape Memory of Poly (acrylamide‐co‐acrylic acid) Grafted on Graphene
Authors: Dong Jun , Ding Jiabao , Weng Jian , Dai Lizong
Published: March 2013

Acrylamide and acrylic acid are grafted on graphene by free‐radical polymerization to produce a series of graphene–poly(acrylamide‐co‐acrylic acid) hybrid materials with different contents of graphene. The materials demonstrate shape memory effect and self‐healing ability when the content of graphene is in the range of 10%–30% even though poly(acrylamide‐co‐acrylic acid) itself had poor shape memory ability. The permanent shape of the materials can be recovered well after 20 cycles of cut and self‐healing. The result is attributed to the hard–soft design that can combine nonreversible “cross‐link” by grafting copolymer on graphene and reversible “cross‐link” utilizing the “zipper effect” of poly(acrylamide‐co‐acrylic acid) to form or dissociate the hydrogen‐bond network stimulated by external heating.

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Synthesis of a Novel Low‐Bandgap Polymer Based on a Ladder‐Type Heptacyclic Arene Consisting of Outer Thieno[3,2‐b]thiophene Units for Efficient Photovoltaic Application
Authors: Xu Xiaofeng , Cai Ping , Lu Yong , Choon Ng Siu , Chen Junwu , Ong Beng S. , Hu Xiao
Published: March 2013

A novel conjugated polymer PIDTT‐quinoxaline (Qx) based on the coplanar thieno[3,2‐b]thiophene‐phenylene‐thieno[3,2‐b]thiophene structure is synthesized and evaluated as an electron‐donor material for bulk‐heterojunction polymer solar cells (BHJ PSCs). The absorption spectra, electrochemical, charge transport, and film morphology properties as well as theoretical modeling of PIDTT‐Qx are investigated to understand its intrinsic structure–property relationship. As expected, this polymer with an extended π‐conjugated backbone exhibits a narrow‐bandgap and board absorption spectrum for enhanced light harvesting. BHJ PSCs (ITO/PEDOT:PSS/polymer:PC71BM/interlayer/Al) afford a maximum power conversion efficiency of 5.05% with an open‐circuit voltage of 0.84 V, a short‐circuit current density of 11.26 mA cm−2, and a fill factor of 53.4%. These results demonstrate the potential of PIDTT‐Qx as an efficient electron‐donor material for BHJ PSCs.

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Cationic Salt‐Responsive Bottle‐Brush Polymers
Authors: Yao Kejian , Chen Ying , Zhang Jun , Bunyard Clay , Tang Chuanbing
Published: March 2013

A class of cationic bottle‐brush polymers that show ionic strength‐dependent stimuli responsiveness is prepared. Brush polymers with norbornene as backbone and quaternary ammonium (QA)‐containing polycaprolactone copolymers as side chains are synthesized by a combination of ring‐opening metathesis polymerization, ring‐opening polymerization, and click reaction. In water with low ionic strength, brush polymers are soluble due to the strong electrostatic repulsion between cationic QA groups. As the addition of salt to increase ionic strength, single brush polymers undergo a transition from extended conformation to collapsed state and finally become insoluble in solution due to the screening effect of salts that yield the once‐dominant electrostatic interactions among QA species to hydrophobic–hydrophobic interactions.

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Tunneling characteristics of superconducting junctions with inhomogeneous tunnel barriers
Authors: Shaternik V. , Shapovalov A. , Belogolovskii M. , Döring S. , Schmidt S. , Seidel P.
Published: March 2013

The increasing interest in charge transport across amorphous nanometer‐thick oxide layers is motivated by their promising applications in semiconductor and superconductor electronics. But usually, electrical characteristics of corresponding devices strongly differ from those following from a conventional theory of tunneling processes. In this work we discuss a possible reason of the anomalous behavior, namely, the presence of an universal bimodal distribution of transparencies across ultra‐thin insulating films. We present low‐temperature current‐voltage characteristics of tunnel junctions with superconducting MoRe alloy electrodes separated by an inhomogeneous nano‐scaled interlayer and found a good agreement between experimental data and numerical results of our theoretical approach.
Ordering kinetics of dopant atoms in graphene lattice with stoichiometric compositions of 1/3 and 1/6
Authors: Radchenko T.M. , Tatarenko V.A.
Published: March 2013

Possible ordered distributions of carbon (C) and substituting dopant (A) atoms over the sites in a graphene‐type lattice are considered for C2A‐ and C5A‐type (super)structures (corresponding to stoichiometries of 1/3 and 1/6, respectively). Relaxation model of atomic long‐range order (LRO) in a graphene‐based lattice is developed, and kinetic curves of the long‐range order parameters are calculated for a wide range of values of temperature and energy parameters. The long‐range order parameters of C2A and C5A structures, described by three long‐range order parameters, can relax nonmonotonically. It is caused by the ‘competition’ of intra‐ and intersublattice interaction energies: the first ones predominate only at the early relaxation stage opposing the ordering, while the second ones predominate at the later relaxation stage and in the equilibrium contributing to the ordering.
Influence of the substrate bias on the stoichiometry and structure of RF‐magnetron sputter‐deposited silver‐containing calcium phosphate coatings
Authors: Ivanova A. A. , Surmeneva M. A. , Grubova I. Y. , Sharonova A. A. , Pichugin V. F. , Chaikina M. V. , Buck V. , Prymak O. , Epple M. , Surmenev R. A.
Published: March 2013

A coating on the basis of silver‐containing hydroxyapatite (silver‐hydroxyapatite) was deposited by radio frequency (RF) magnetron sputtering. X‐ray diffractometry, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and ellipsometry were used to analyse the change in structure and stoichiometry of the coatings upon the change of the negative electrical bias (–50 V and –100 V) on the substrate. The chemical composition of the sputter‐deposited coating was identical to the target. However, an increase in the negative electrical bias on the substrate led to a decrease of the coating thickness. In addition, the average size of the grains decreased from 55 ± 15 nm (grounded substrate) up to 30 ± 10 nm when an electrical bias of –100 V was applied.
Impact of single‐walled carbon nanotubes on the medullary neurons in spontaneously hypertensive rats
Authors: Radchenko N.V. , Prylutskyy Yu.I. , Shapoval L.M. , Sagach V.F. , Davydovska T.L. , Dmitrenko O.V. , Stepanenko L.G. , Pobigailo L.S. , Schütze Ch. , Ritter U.
Published: March 2013

The effect of single‐walled carbon nanotubes (SWCNTs) on the nervous cardiovascular control in normotensive (NTR) and spontaneously hypertensive rats (SHR) was studied. SWCNTs were injected into the medullary nuclei involved in the neural control of the cardiovascular system (nucleus of tractus solitarius (NTS); nucleus ambiguus (AMB), paramedian reticular nucleus (PMn), and lateral reticular nucleus (LRN)). It was found that SWCNT microinjections into all the studied medullary nuclei of both NTR and SHR resulted in a lowering of the arterial pressure more essential in SHR compared to those in NTR.
Effect of adsorbed magnetic and non‐magnetic atoms on electronic transport through surfaces with strong spin‐orbit coupling
Authors: Lükermann D. , Sologub S. , Pfnür H. , Klein C. , Horn‐von‐Hoegen M. , Tegenkamp C.
Published: March 2013

Adsorption‐induced reduction of the surface state conductivity in epitaxial Bi(111) films, a prototype system with a large Rashba‐induced surface state splitting by adsorbed atoms of Bi, Fe and Co was investigated by macroscopic surface magneto‐transport measurements at a temperature of 10 K. A detailed analysis of magneto‐transport, DC‐transport and Hall data reveals that the scattering efficiencies for Co and Fe are by a factor of two larger than for Bi. While for the latter, charge transfer and change of band filling near the Fermi level is negligible, we found an increase of hole concentration upon Co and Fe adsorption. These atoms act as acceptors and retract roughly 0.5 electrons from the surface per adsorbed atom. Besides the dominant classical magneto‐conductance signal the films show signatures of weak anti‐localization (WAL) reflecting the strong spin‐orbit coupling in Bi(111) surface states. Our measurements show that the control of hybridization is important in order to make use of local spin‐moments and to increase the backscattering rate in strongly spin‐orbit coupled systems, e. g., topological insulators.
Electrical conductivity of epoxy resin filled with graphite nanoplatelets and boron nitride
Authors: Matzui L. Y. , Vovchenko L. L. , Perets Y. S. , Lazarenko O. A.
Published: March 2013

The electrical conductivity of polymer composites with mixture of fillers, i. e. graphite nanoplatelets and hexagonal boron nitride (BN), was investigated. The content of graphite nanoplatelets (prepared by ultrasonication of thermoexfoliated graphite) in composite materials varied from 2 to 10 wt%. The DC conductivity was measured by the two‐ or four‐probe methods in the temperature range of 77–293 K. A model of the electrical conductivity of composite materials was proposed. It takes into account the conductivity of the graphite particles, the contact resistance between particles, and the number of electrically conducting chains from graphite particles. In the framework of this model the number of graphite chains and the contact resistance of investigated composite materials were calculated. It was shown that the addition of boron nitride increases the number of electrically conducting chains from the graphite particles, decreases the value of contact resistance Rk between graphite particles that leads to smaller changes of contact resistance with increasing temperature, and weakens the temperature dependence of electrical conductivity of composite materials.
Dynamic model of integrated cardiovascular and respiratory systems
Authors: Lee Rong‐Mao , Tsai Nan‐Chyuan
Published: March 2013

A set of linear time‐variant dynamic models for the interactive respiratory/cardiovascular mechanism is constructed and analyzed in this work. By using equivalent electric circuits for heart/blood and lung/air subsystems, the dynamics of cardiovascular subsystem and respiration cycle are established. In order to verify the validity of the dynamic models, numerical simulations and analysis on heart–lung interactions, including the valvular closure incompetence and pulmonary obstruction, are presented and compared with the empirical reports in literature. The derived dynamics of heart–lung interactions can be realized and examined in the biomechanical and medical engineering fields. In addition, the dynamic models can also be used for the model‐based controller synthesis in medical instrumentations, for example, the extracorporeal membrane oxygenation, to retain the function of blood circulation and/or respiration by artificial intelligence. Copyright © 2013 John Wiley & Sons, Ltd.
Approximation properties of a class of linear operators
Authors: Agratini Octavian
Published: March 2013

This work focuses on a class of linear positive operators of discrete type. We present the relationship between the local smoothness of functions and the local approximation. Also, the degree of approximation in terms of the moduli of smoothness is established, and the statistical convergence of the sequence is studied. Copyright © 2013 John Wiley & Sons, Ltd.
Resveratrol metabolites inhibit human metastatic colon cancer cells progression and synergize with chemotherapeutic drugs to induce cell death
Authors: Aires Virginie , Limagne Emeric , Cotte Alexia K. , Latruffe Norbert , Ghiringhelli François , Delmas Dominique
Published: March 2013

Scope

Resveratrol (RSV) has been proposed to prevent tumor growth; nevertheless, these preventive effects are controversial since RSV pharmacokinetics studies show a low bioavailability. Recent clinical trials show that patients with colorectal cancer and receiving oral RSV have high levels of RSV conjugates in the colorectum, mainly RSV‐3‐O‐sulfate (R3S), RSV‐3‐O‐glucuronide, and RSV‐4′‐O‐glucuronide. However, their potential biological activity has not yet been established. This study thus investigated in human colorectal cancer cell lines whether RSV main metabolites retain anticarcinogenic properties as their parental molecule.

Methods and results

Proliferation, apoptosis assays and cell cycle analysis were performed to study the effect of RSV, R3S, RSV‐3‐O‐glucuronide, or RSV‐4′‐O‐glucuronide alone or of a mixture of the three metabolites. R3S inhibits colon cancer cells proliferation and an accumulation of cells in S phase. Interestingly, the mixture induced a synergistic effect. This process was associated with an induction of DNA damages and apoptotic process, which allowed sensitization of colon cancer cells to the anticancer drugs.

Conclusion

Altogether, our data provide significant new insight into the molecular mechanism of RSV and support the notion that despite low bioavailability in vivo, RSV biological effects could be mediated by its metabolites.
Three‐dimensional ultrasound demonstration of the fetal palate in high‐risk patients: the accuracy of prenatal visualization
Authors: Gindes Liat , Weissmann‐Brenner Alina , Zajicek Michal , Weisz Boaz , Shrim Alon , Geffen Keren Tzadikevitch , Mendes David , Kuint Jaacov , Berkenstadt Michal , Achiron Reuven
Published: March 2013

Objective

The aim of this research was to evaluate the ability of three‐dimensional (3D) ultrasound for demonstrating the palate of fetuses at high risk for cleft palate.

Method

Fifty‐seven fetuses at high risk for cleft palate were referred for specialist ultrasound at 12–40 weeks' gestation. A detailed assessment of palate was made using both two‐dimensional and 3D ultrasounds on the axial plane. Antenatal diagnoses were compared with postnatal findings.

Results

Cleft palate was suspected in 13 (22.8%); a normal palate was demonstrated in 38 (67%), and in six (10.2%), the palate view could not be obtained. Mean gestational age at the first visit was 27 weeks 6 days (range of 12–40 weeks 3 days). Examination after delivery revealed that one of the 38 fetuses with presumed normal palate had a cleft hard palate, and one had a cleft soft palate (false negative 5%). Among the 13 fetuses with suspected cleft palate, three had an intact palate (false‐positive 23%). Sensitivity, specificity, positive predictive value, and negative predictive value of detection of palatal clefts were 71.4%, 91.9%, 62.5%, and 94.4%, respectively.

Conclusion

Using 3D technology, we diagnosed a cleft palate in 83% of high‐risk cases, with 5% false negative. 3D technology might produce some technical artifacts resulting in a 23% false‐positive rate. © 2013 John Wiley & Sons, Ltd.
Sulfonation of polystyrene: Toward the “ideal” polyelectrolyte
Authors: Coughlin Jessica E. , Reisch Andreas , Markarian Marie Z. , Schlenoff Joseph B.
Published: March 2013

Sulfonation of narrow polydispersity polystyrene, PS, standards remains the method of choice for generating polystyrene sulfonate, PSS, samples with defined composition. Although a variety of sulfonation techniques have been described, relatively little is reported on the material obtained, which is used for so many studies on the fundamental behavior of polyelectrolytes. Here, we show that powdered polystyrene treated with concentrated sulfuric acid (96%) at 90 °C without catalyst yields fully sulfonated PSS. Extensive characterization with 1H and 13C NMR as well as size exclusion chromatography coupled with static and dynamic light scattering shows no evidence of sulfone crosslinking or chain degradation under the conditions used. Though mono‐sulfonated as soon as it dissolves in the acid, the PSS contains about 6% meta substitution. Sulfonation kinetics for this heterogeneous reaction depend strongly on particle size, sulfuric acid content and temperature. For preparing perdeuterated PSS from the corresponding PS it is essential to employ D2SO4, as about half of the aromatic units undergo H/D exchange during sulfonation. The remaining ortho H/D may be exchanged with extended exposure to the concentrated sulfuric acid, but the meta site is deactivated. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2416–2624
Noncovalent linkage of telechelic oligo(dimethylsiloxanes) via end group attachment of host‐cyclodextrins and guest‐adamantanes or guest‐ferrocenes
Authors: Knudsen Berit , Kergl Beate E. , Paulsen Helene , Durnev Valerij , Ritter Helmut
Published: March 2013

In this article, we report the noncovalent linkage of terminal substituted oligo(dimethylsiloxanes) bearing cyclodextrins (CD) as host endgroups and adamantan or ferrocene, respectively, as guest endgroups. Structural characterization was performed by 1H NMR‐, IR‐, and mass spectroscopy. Electron microscopy studies show significant differences in the surface structure of the individual derivatives. In addition, the ferrocene‐terminated di‐and poly(dimethylsiloxanes) are distinguished by a red‐ox activity and reversibility, which also makes the complexes between the ferrocene‐ and CD functionalized siloxanes switchable via electrochemical stimuli. The evidence for a successful complexation of the end groups, and thus the successful supramolecular formation of the siloxane strands, was even performed by shift of the protons in the 1H NMR spectra. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2472–2482
Limitations of cyclodextrin‐mediated RAFT homopolymerization and block copolymer formation
Authors: Hetzer Martin , Schmidt Bernhard V. K. J. , Barner‐Kowollik Christopher , Ritter Helmut
Published: March 2013

The design and synthesis of a new hydrophobic monomer, that is, 4‐(tert‐butyl)phenyl 6‐acrylamidohexanoate (TBP‐AA‐HO) and its ability to form supramolecular host/guest complexes with β‐cyclodextrin (CD) is described. The aqueous CD‐mediated reversible addition fragmentation chain transfer (RAFT) polymerization affords molecular masses up to 8600 g mol−1 with polydispersities between 1.2 and 1.4. The surprisingly low molecular weights for higher monomer/chain transfer agent (CTA) ratios are investigated by comparing results obtained from free radical and RAFT radical polymerization in aqueous and organic media. The results indicate a steric hindrance caused by attached CD molecules on the growing polymer chain leading to stagnation of the polymerization process due to a restricted accessibility of the reactive chain end. This hypothesis is supported by matrix‐assisted laser desorption/ionization time of flight mass spectrometry. Furthermore, the CD‐mediated synthesis of amphiphilic diblock copolymers in variable aqueous media is described. Hydrophilic poly(N,N‐dimethylacrylamide) macro‐CTAs with different molecular weights are used to polymerize TBP‐AA‐HO at 50 °C. The diblock copolymers are analyzed by 1H‐nuclear magnetic resonance spectroscopy and size exclusion chromatography. The results confirm the polymer structure and reveal similar limitations of chain growth as observed for the CD‐mediated homopolymerization with a limit of 7000 g mol−1 for efficient chain extension. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2504–2517
Plasma Etching of Silk Fibroin: Experiments and Models
Authors: Narayanamoorthy Jayasri , Tsioris Konstantinos , Omenetto Fiorenzo G. , Hopwood Jeffrey
Published: March 2013

Silk fibroin biopolymer is anisotropically etched using oxygen and argon/oxygen plasma. At room temperature, silk removal rates are 0.25 µm min−1. Scanning electron micrographs show that silk fibroin is a heterogeneous material for which plasma etching reveals a silk backbone structure as the matrix is more quickly volatilized. A simple physical model of silk etching accurately predicts the etch rate without any fitting parameters. The model and experimental data show that atomic oxygen, in the absence of ion bombardment, only slowly etches silk (<0.017 µm min−1) and does not spontaneously etch silk fibroin backbone structures. Rather, the silk constituents must be removed by first covering the surface with adsorbed atomic oxygen which is then simultaneously desorbed through energetic ion bombardment.

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Syngenetic Ice Wedges: Cyclical Formation, Radiocarbon Age and Stable Isotope Records by Yurij K. Vasil’chuk, Moscow University Press, Moscow, 2006. 404 pp. ISBN 5‐211‐05212‐9
Authors: Vasil'chuk Yurij K.
Published: March 2013

The monograph summarises radiocarbon and stable isotope research on syngenetic ice wedges. The southern boundary of active and inactive ice wedges in Russian permafrost is re‐evaluated and revised. A new model of cyclical growth of syngenetic ice wedges is proposed, involving three cycles in ice‐wedge development: micro‐, meso‐ and macrocycles. Direct dating of syngenetic ice wedges can be carried out by accelerator mass spectrometry (AMS) radiocarbon dating of organic microinclusions and pollen concentrates from ice‐wedge ice. Dating reveals vertical and lateral variation in the age of yedoma at Duvanny Yar (NE Yakutia), one of the key syngenetic permafrost exposures in Eurasia. Radiocarbon ages and oxygen and deuterium isotopic values of syngenetic ice wedges in northern Russia and North America provide insights into palaeoenvironmental history and palaeogeocryology. Syngenetic ice wedges sometimes show complex cryostratigraphic relationships with other types of ice, including massive ice, icing ice and pingo ice. Comparison of isotope records from syngenetic ice wedges with those from Greenland ice cores reveals evidence for Dansgaard‐Oeschger (D/O) events preserved in Siberian permafrost. Copyright © 2013 John Wiley & Sons, Ltd.
Biodegradable paclitaxel‐loaded microparticles prepared from novel block copolymers: influence of polymer composition on drug encapsulation and release
Authors: Sartori Susanna , Caporale Andrea , Rechichi Alfonsina , Cufari Domenico , Cristallini Caterina , Barbani Niccoletta , Giusti Paolo , Ciardelli Gianluca
Published: March 2013

This study covers the preparation of microspheres for the controlled and targeted release of paclitaxel, using novel degradable polymers as carrier materials. Paclitaxel‐loaded microspheres were prepared by oil‐in‐water single‐emulsion solvent extraction/evaporation technique by using a series of polyurethanes and a block copolymer; the physicochemical properties of these polymers were modulated by changing nature and composition of their structural units. The obtained microparticles showed a regular morphology and properties (diameter: 1–100 µm; resuspension index: 18.8–100%; encapsulation efficiency: 26.6–97.2%) depending on polymer hydrophilicity and emulsifier used. In vitro release curves showed in all cases almost zero‐order kinetics after an initial low burst effect (from 1 to 8.4%), which is required to minimize the drug side effects.

This work also proposes a novel strategy to combine a controlled and a targeted release through the functionalization of the polymer matrix with peptide sequences. An RGD‐functionalized polyurethane was used to successfully prepare paclitaxel‐loaded microparticles. Studies on the preparation of polymer microspheres are reported. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
Electrospray ion source with a dynamic liquid flow splitter
Authors: Samokish V. A. , Muradymov M. Z. , Krasnov N. V.
Published: March 2013

RATIONALE

Although the electrospray method is widely used in biomedical mass spectrometry and ion‐drift spectrometry, the electrospray system can generate large drops that are the cause of electrical breakdowns, and of the fast clogging of the inlet diaphragm of the differential pumping first stage and system of ion transportation to the analyzer. Thus, a system free of such problems would be of benefit.

METHODS

To drain the condensate away from the electrospraying zone and to maintain stability of spraying, a source was designed where the excessive non‐sprayed solution flowing down over the metal capillary outer wall is pumped away by an air micropump. An anti‐electrode is mounted opposite the metal capillary and is slightly tilted with respect to the horizon to make the condensed liquid flow down.

RESULTS

An electrospray ion source allowing work with chromatographic flows of the solution under normal conditions was tested. The applicability of the operating modes of the electrospray ion source with dynamic liquid flow splitting for both ion‐drift and mass spectrometers was demonstrated. The flow rate range of liquid fed to the electrospray ion source with dynamic liquid flow splitting is such that it can be used in high performance liquid chromatography/Ion Mobility Spectrometry (HPLC/IMS) and HPLC/MS in the online mode.

CONCLUSIONS

An electrospray ion source with a dynamic liquid flow splitter was developed and tested. Optimal operating modes of the electrospray ion source with dynamic liquid flow splitting were determined. Copyright © 2013 John Wiley & Sons, Ltd.
Effects of euthanasia method on stable‐carbon and stable‐nitrogen isotope analysis for an ectothermic vertebrate
Authors: Atwood Meredith A.
Published: March 2013

RATIONALE

Stable isotope analysis is a critical tool for understanding ecological food webs; however, results can be sensitive to sample preparation methods. To limit the possibility of sample contamination, freezing is commonly used to euthanize invertebrates and preserve non‐lethal samples from vertebrates. For destructive sampling of vertebrates, more humane euthanasia methods are preferred to freezing and it is essential to evaluate how these euthanasia methods affect stable isotope results.

METHODS

Stable isotope ratios and elemental composition of carbon and nitrogen were used to evaluate whether the euthanasia method compromised the integrity of the sample for analysis. Specifically, the stable isotope and C:N ratios were compared for larval wood frogs (Rana sylvatica = Lithobates sylvaticus), an ectothermic vertebrate, that had been euthanized by freezing with four different humane euthanasia methods: CO2, benzocaine, MS‐222 (tricaine methanesulfonate), and 70% ethanol.

RESULTS

The euthanasia method was not related to the δ13C or δ15N values and the comparisons revealed no differences between freezing and any of the other treatments. However, there were slight (non‐significant) differences in the isotope ratios of benzocaine and CO2 when each was compared with freezing. The elemental composition was altered by the euthanasia method employed. The percentage nitrogen was higher in CO2 treatments than in freezing, and similar (non‐significant) trends were seen for ethanol treatments relative to freezing. The resulting C:N ratios were higher for benzocaine treatments than for both CO2 and ethanol. Similar (non‐significant) trends suggested that the C:N ratios were also higher for animals euthanized by freezing than for both CO2 and ethanol euthanasia methods.

CONCLUSIONS

The euthanasia method had a larger effect on elemental composition than stable isotope ratios. The percentage nitrogen and the subsequent C:N ratios were most affected by the CO2 and ethanol euthanasia methods, whereas non‐significant trends suggested that benzocaine and CO2 altered the stable isotope ratios. It appears that the use of MS‐222 and freezing with dry ice are the most appropriate euthanasia methods for ectothermic vertebrates. Copyright © 2013 John Wiley & Sons, Ltd.
Fault detection for LPV systems using model parameters that can be estimated via linear least squares
Authors: Dong Jianfei , Kulcsár Balázs , Verhaegen Michel
Published: March 2013

This paper presents a fault detection approach for discrete‐time affine linear parameter varying systems with additive faults. A finite horizon input‐output linear parameter varying model is used to obtain a linear in the model parameter regression residual form. The bias in the residual term vanishes because of quadratic stability of an underlying observer. The new methodology avoids projecting the residual onto a parity space, which in real time requires at least quadratic computational complexity. When neglecting the bias, the fault detection is carried out by an χ2 hypothesis test. Finally, the algorithm uses model parameters that can be identified prior to the on‐line fault detection with linear least squares. A realtime experiment is carried out to demonstrate the viability of the proposed method. Copyright © 2013 John Wiley & Sons, Ltd.
Sets that are connected in two random graphs
Authors: Molloy Michael
Published: March 2013

–We consider two random graphs G1, G2, both on the same vertex set. We ask whether there is a non‐trivial set of vertices S, so that S induces a connected subgraph both in G1 and in G2. We determine the threshold for the appearance of such a subset, as well as the size of the largest such subset. © 2013 Wiley Periodicals, Inc. Random Struct. Alg., 45, 498–512, 2014
Detecting stepping‐stone intrusion using association rule mining
Authors: Hsiao Han‐Wei , Sun Huey‐Min , Fan Wei‐Cheng
Published: March 2013

Hackers generally do not use their own computers to launch attacks on the Internet to avoid exposing their actual locations. The trick involves an intruder connecting to a victim indirectly through a sequence of hosts called stepping‐stone, which makes network managers difficult to detect the intrusion, often results in serious injuries. In this study, a detection method of stepping‐stone based on the association rule mining of network traffic records is proposed. The association rules establish a model for detecting stepping‐stones in accordance with collecting the connecting records in the governed network. Test records are gathered from the source and destination addresses of Internet protocol in a fixed time interval, which are then analyzed with the association rules algorithm to filter out the transmission characteristics of stepping‐stone attacks. In the experimental results, empirical evaluation under 5 min of test records shows that the accuracy rate, the precision rate, and the recall rate are 83.81%, 84.26%, and 83.16%, respectively. When the test record gathering time is extended to 20 min, with the same detecting method, the three evaluations achieve 99.9%. The proposed detection method may be helpful to network management for detecting suspected stepping‐stone attacks. Copyright © 2013 John Wiley & Sons, Ltd.
A probabilistic quantum key transfer protocol
Authors: Parakh Abhishek
Published: March 2013

We propose a protocol to transfer a one‐time pad (in a probabilistic manner) from Alice to Bob, over a public channel. The proposed protocol is unique because Bob merely acts as a receiver of the pad (secret key); that is, Bob does not need to send any message back to Alice unless he detects eavesdropping. Such a secure transfer of one‐time pad, over public channel, is not possible in classical cryptography, and in quantum cryptography, all previous protocols require Bob to send almost as many messages back to Alice as she does to Bob to establish a key. Copyright © 2013 John Wiley & Sons, Ltd.
Graphene‐Based Electrochemical Sensors
Authors: Wu Shixin , He Qiyuan , Tan Chaoliang , Wang Yadong , Zhang Hua
Published: March 2013

Graphene, one kind of emerging carbon nanomaterial, has attracted increasing attention recently. Due to its fascinating physical and electrochemical properties, graphene as a promising electrode material has been widely used in electrochemical sensing applications. In this review, different approaches for the fabrication of graphene and the preparation of graphene‐modified electrodes for electrochemical sensors are introduced. Moreover, recent research results on different graphene‐based materials as an electrochemical platform for the detection of various biomolecules and chemicals are reviewed and compared. More electrochemical studies on this novel material should show up in the near future.
Low power wind energy conversion system based on variable speed permanent magnet synchronous generators
Authors: Carranza O. , Garcerá G. , Figueres E. , González L.G.
Published: March 2013

This paper presents a low power wind energy conversion system (WECS) based on a permanent magnet synchronous generator and a high power factor (PF) rectifier. To achieve a high PF at the generator side, a power processing scheme based on a diode rectifier and a boost DC–DC converter working in discontinuous conduction mode is proposed. The proposed generator control structure is based on three cascaded control loops that regulate the generator current, the turbine speed and the amount of power that is extracted from the wind, respectively, following the turbine aerodynamics and the actual wind speed. The analysis and design of both the current and the speed loops have been carried out taking into consideration the electrical and mechanical characteristics of the WECS, as well as the turbine aerodynamics. The power loop is not a linear one, but a maximum power point tracking algorithm, based on the Perturb and Observe technique, from which is obtained the reference signal for the speed loop. Finally, to avoid the need of mechanical sensors, a linear Kalman Filter has been chosen to estimate the generator speed. Simulation and experimental results on a 2‐kW prototype are shown to validate the concept. Copyright © 2013 John Wiley & Sons, Ltd.
Evaluating controls on coupled hydrologic and vegetation dynamics in a humid continental climate watershed using a subsurface‐land surface processes model
Authors: Shen Chaopeng , Niu Jie , Phanikumar Mantha S.
Published: March 2013

Key Points

Evaluated relative controls on hydrologic and vegetation fluxes and states

Evaluated the coupling strengths between biogeochemical and hydrologic cycles

Elucidated patterns of hydrology and vegetation dynamics in a Great Lakes basin
Threshold behavior in a fissured granitic catchment in southern China: 1. Analysis of field monitoring results
Authors: Fu Congsheng , Chen Jianyao , Jiang Huabo , Dong Linyao
Published: March 2013

Key Points

Both the plot and catchment scales.
Evaluation of groundwater depletion in North China using the Gravity Recovery and Climate Experiment (GRACE) data and ground‐based measurements
Authors: Feng Wei , Zhong Min , Lemoine Jean‐Michel , Biancale Richard , Hsu Hou‐Tse , Xia Jun
Published: March 2013

Key Points

GRACE detects the groundwater depletion in North China.

Official report underestimates the groundwater depletion rate in North China.

High groundwater depletion exists in Beijing and Hebei province.
Breeding melon for resistance to Fusarium wilt: recent developments
Authors: Oumouloud A. , El-Otmani M. , Chikh-Rouhou H. , Claver A. Garcés , Torres R. González , Perl-Treves R. , Álvarez J. M.
Published: March 2013

Melon Fusarium wilt (MFW), caused byFusarium oxysporumf. sp.melonis(Fom), is one of the most destructive diseases of melon (Cucumis meloL.). The development and deployment of resistant cultivars is generally considered to be the best approach to control MFW. Based on the host resistance genes associated with variants of this pathogen,Fomisolates were classified into four physiological races designated 0, 1, 2, and 1,2. Two dominant resistance genes,Fom-1andFom-2, control resistance to races 0 and 2, and 0 and 1, respectively.Fomisolates classified as race 1,2 are able to induce disease in melon lines carrying the above resistance genes. Many sources of resistance toFomraces 0, 1, and 2 have been reported. Partial resistance to race 1,2 controlled by polygenic recessive genes was only detected in a few Far Eastern melon accessions, except for the breeding line BIZ where complete resistance was described. Identification of DNA markers tightly linked to genes conferring resistance toFomhas immediate application in MFW resistance breeding programs. TheFom-2gene has been cloned, and it encodes a protein with a nucleotide binding site (NBS) and leucine-rich repeats domain (LRR). Based on the sequence of this domain, some molecular markers linked to this gene were developed. Several DNA markers linked toFom-1have also been described. However, the usefulness of these markers was variety-dependent. Therefore, their combined use would be very useful in marker assisted selection for introducing resistance toFomraces 0 and 2 in melon. Recently, these markers were used for the positional cloning of this gene, which encoded a protein with a NBS–LRR domains that shows similarity to the toll and interleukin-1 receptores (TIR). RegardingFomrace 1,2, nine QTL were detected on five linkage groups by composite interval mapping. In this paper we review the current knowledge of MFW disease, and focus on genetic resistance toFomand marker-assisted selection for resistance.
Egg Consumption Modulates HDL Lipid Composition and Increases the Cholesterol‐Accepting Capacity of Serum in Metabolic Syndrome
Authors: Andersen Catherine J. , Blesso Christopher N. , Lee Jiyoung , Barona Jacqueline , Shah Dharika , Thomas Michael J. , Fernandez Maria Luz
Published: March 2013

We recently demonstrated that daily whole egg consumption during moderate carbohydrate restriction leads to greater increases in plasma HDL‐cholesterol (HDL‐C) and improvements in HDL profiles in metabolic syndrome (MetS) when compared to intake of a yolk‐free egg substitute. We further investigated the effects of this intervention on HDL composition and function, hypothesizing that the phospholipid species present in egg yolk modulate HDL lipid composition to increase the cholesterol‐accepting capacity of subject serum. Men and women classified with MetS were randomly assigned to consume either three whole eggs (EGG, n = 20) per day or the equivalent amount of egg substitute (SUB, n = 17) throughout a 12‐week moderate carbohydrate‐restricted (25–30 % of energy) diet. Relative to other HDL lipids, HDL‐cholesteryl ester content increased in all subjects, with greater increases in the SUB group. Further, HDL‐triacylglycerol content was reduced in EGG group subjects with normal baseline plasma HDL‐C, resulting in increases in HDL‐CE/TAG ratios in both groups. Phospholipid analysis by mass spectrometry revealed that HDL became enriched in phosphatidylethanolamine in the EGG group, and that EGG group HDL better reflected sphingomyelin species present in the whole egg product at week 12 compared to baseline. Further, macrophage cholesterol efflux to EGG subject serum increased from baseline to week 12, whereas no changes were observed in the SUB group. Together, these findings suggest that daily egg consumption promotes favorable shifts in HDL lipid composition and function beyond increasing plasma HDL‐C in MetS.
The last generation of the pommy medical officer
Authors: Armstrong A.
Published: March 2013

None
On the Cauchy problem of a weakly dissipative μ-Hunter–Saxton equation
Authors: Liu Jingjing , Yin Zhaoyang
Published: March 2013

In this paper, we study the Cauchy problem of a weakly dissipative
μ
-Hunter–Saxton equation. We first establish the local well-posedness for the weakly dissipative
μ
-Hunter–Saxton equation by Kato's semigroup theory. Then, we derive the precise blow-up scenario for strong solutions to the equation. Moreover, we present some blow-up results for strong solutions to the equation. Finally, we give two global existence results to the equation.
Interpretation, Stratification and Evidence for Sequence Variants Affecting mRNA Splicing in Complete Human Genome Sequences
Authors: Shirley Ben C. , Mucaki Eliseos J. , Whitehead Tyson , Costea Paul I. , Akan Pelin , Rogan Peter K.
Published: March 2013

Information theory-based methods have been shown to be sensitive and specific for predicting and quantifying the effects of non-coding mutations in Mendelian diseases. We present the Shannon pipeline software for genome-scale mutation analysis and provide evidence that the software predicts variants affecting mRNA splicing. Individual information contents (in bits) of reference and variant splice sites are compared and significant differences are annotated and prioritized. The software has been implemented for CLC-Bio Genomics platform. Annotation indicates the context of novel mutations as well as common and rare SNPs with splicing effects. Potential natural and cryptic mRNA splicing variants are identified, and null mutations are distinguished from leaky mutations. Mutations and rare SNPs were predicted in genomes of three cancer cell lines (U2OS, U251 and A431), which were supported by expression analyses. After filtering, tractable numbers of potentially deleterious variants are predicted by the software, suitable for further laboratory investigation. In these cell lines, novel functional variants comprised 6–17 inactivating mutations, 1–5 leaky mutations and 6–13 cryptic splicing mutations. Predicted effects were validated by RNA-seq analysis of the three aforementioned cancer cell lines, and expression microarray analysis of SNPs in HapMap cell lines.
Possible contribution of lower mantle magnesiowüstite metallization into geomagnetic data
Authors: Plotkin V.V. , Dyad’kov P.G. , Ovchinnikov S.G.
Published: March 2013

Phase change of dielectric magnesiowüstite in the lower mantle may leave signatures in geomagnetic records of the globally distributed array of observatories. We investigate theoretically which may be the contribution of magnesiowüstite metallization to geomagnetic data and how the variations of magnetic susceptibility associated with this phase change may influence the Earth’s field. The modeling is performed using spherical harmonic analysis (SHA) of mantle electromagnetic (EM) responses in observatory geomagnetic data at periods of decades, 11 years, 1 year, and 27 days. The existence of a lower mantle conductor is checked against monthly means of real observatory records from 1920 through 2009 obtained by preliminary processing.
Traces of paleoearthquakes in the Quaternary deposits of intermontane basins in central Gorny Altai
Authors: Deev E.V. , Zolnikov I.D. , Goltsova S.V. , Rusanov G.G. , Emanov A.A.
Published: March 2013

Study of the sections of Neopleistocene–Holocene deposits filling the basins in central Gorny Altai has revealed earthquake-induced soft-sediment deformation (seismites). They formed as a result of the brittle deformation of deposits and liquefaction of loose water-saturated sediments under vibration seismic impact. The paleoearthquakes resulting in such seismites had the minimum intensity I = 6 and magnitude M = 5–6. Hence, the study region underwent strong earthquakes in the Neopleistocene–Holocene.
Discourse Analysis
Authors: Brown Gillian , Yule George
Published: March 2013

Discourse analysis is a term that has come to have different interpretations for scholars working in different disciplines. For a sociolinguist, it is concerned mainly with the structure of social interaction manifested in conversation; for a psycholinguist, it is primarily concerned with the nature of comprehension of short written texts; for the computational linguist, it is concerned with producing operational models of text-understanding within highly limited contexts. In this textbook, first published in 1983, the authors provide an extensive overview of the many and diverse approaches to the study of discourse, but base their own approach centrally on the discipline which, to varying degrees, is common to them all - linguistics. Using a methodology which has much in common with descriptive linguistics, they offer a lucid and wide-ranging account of how forms of language are used in communication. Their principal concern is to examine how any language produced by man, whether spoken or written, is used to communicate for a purpose in a context.
A multi-fidelity modelling approach for evaluation and optimization of wing stroke aerodynamics in flapping flight
Authors: Zheng Lingxiao , Hedrick Tyson L. , Mittal Rajat
Published: March 2013

The aerodynamics of hovering flight in a hawkmoth (Manduca sexta) are examined using a computational modelling approach which combines a low-fidelity blade-element model with a high-fidelity Navier–Stokes-based flow solver. The focus of the study is on understanding the optimality of the hawkmoth-inpired wingstrokes with respect to lift generation and power consumption. The approach employs a tight coupling between the computational models and experiments; the Navier–Stokes model is validated against experiments, and the blade-element model is calibrated with the data from the Navier–Stokes modelling. In the first part of the study, blade-element and Navier–Stokes modelling are used concurrently to assess the predictive capabilities of the blade-element model. Comparisons between the two modelling approaches also shed insights into specific flow features and mechanisms that are lacking in the lower-fidelity model. Subsequently, we use blade-element modelling to explore a large kinematic parameter space of the flapping wing, and Navier–Stokes modelling is used to assess the performance of the wing-stroke identified as optimal by the blade-element parameter survey. This multi-fidelity optimization study indicates that even within a parameter space constrained by the animal’s natural flapping amplitude and frequency, it is relatively easy to synthesize a wing stroke that exceeds the aerodynamic performance of the hawkmoth wing stroke. Within the prescribed constraints, the optimal wing stroke closely approximates the condition of normal hover, and the implications of these findings on hawkmoth flight capabilities as well as on the issue of biomimetic versus bioinspired design of flapping wing micro-aerial vehicles, are discussed.
Gene cloning and expression patterns of two prophenoloxidases fromCatantops pinguis(Orthoptera: Catantopidae)
Authors: Zheng Huizhen , Li Lingshun , Xu Qi , Zou Qi , Tang Bin , Wang Shigui
Published: March 2013

In insect, fat body plays major roles in insect innate immunity. Phenoloxidase (PO) is an important component in insect innate immunity and is necessary for acclimatization. In our study, two prophenoloxidase (PPO) subunits were obtained from fat body ofCatantops pinguis(Stål). The full-length cDNA sequence of one PPO (CpPPO1) consisted of 2347 bp with an open reading frame (ORF) of 2187 bp encoding 728 amino acids, while the other subunit (CpPPO2) had a full length of 2445 bp, encoding 691 amino acids. Both thePPOgene products are predicted to possess all the structural features of other PPO members, including two putative tyrosinase copper-binding motifs with six highly conserved histidine residues and a thiolester-like motif. Tissue distribution analysis showed that bothPPOmRNAs were abundantly expressed in the fat body among 11 tissues examined, and they were transiently up-regulated afterEscherichia coliinfection, consistent with them being immune-responsive genes. Total levels ofCpPPO1 andCpPPO2 mRNA transcripts were much higher in first instar larvae and adults. A much higher transcript level ofCpPPO1 was detected in several months, while there were extremely high mRNA expression levels ofCpPPO2 in January, July, October, and December. The above results suggested that PPO from fat body might also bring significant function during the processes of development and acclimatization forC. pinguis.