bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection and molecular characterisation of Pyrenopeziza brassicae isolates resistant to methyl benzimidazole carbamates
Authors: Carter Helen E , Cools Hans J , West Jonathan S , Shaw Michael W , Fraaije Bart A
Published: June 2013

BACKGROUND

Methyl benzimidazole carbamate (MBC) fungicides are used to control the oilseed rape pathogen Pyrenopeziza brassicae. Resistance to MBCs has been reported in P. brassicae, but the molecular mechanism(s) associated with reductions in sensitivity have not been verified in this species. Elucidation of the genetic changes responsible for resistance, hypothesised to be target‐site mutations in β‐tubulin, will enable resistance diagnostics and thereby inform resistance management strategies.

RESULTS

P. brassicae isolates were classified as sensitive, moderately resistant or resistant to MBCs. Crossing P. brassicae isolates of different MBC sensitivities indicated that resistance was conferred by a single gene. The MBC‐target encoding gene β‐tubulin was cloned and sequenced. Reduced MBC sensitivity of field isolates correlated with β‐tubulin amino acid substitutions L240F and E198A. The highest level of MBC resistance was measured for isolates carrying E198A. Negative cross‐resistance between MBCs and the fungicides diethofencarb and zoxamide was only measured in E198A isolates. PCR‐RFLP was used to screen isolates for the presence of L240F and E198A. The substitutions E198G and F200Y were also detected in DNA samples from P. brassicae populations after cloning and sequencing of PCR products. The frequencies of L240F and E198A in different P. brassicae populations were quantified by pyrosequencing. There were no differences in the frequencies of these alleles between P. brassicae populations sampled from different locations or after fungicide treatment regimes.

CONCLUSIONS

The molecular mechanisms affecting sensitivity to MBCs in P. brassicae have been identified. Pyrosequencing assays are a powerful tool for quantifying fungicide‐resistant alleles in pathogen populations. © 2013 Society of Chemical Industry
Measurement Plan Optimization for Degradation Test Design based on the Bivariate Wiener Process
Authors: Jin Guang , Matthews David
Published: June 2013

This article concerns the optimization of measurement plans in the design of bivariate degradation tests for bivariate Wiener processes. After describing an unbalanced measurement scheme for bivariate degradation tests, we derive the likelihood function and provide a method for estimating the model parameters that is based on maximum likelihood and least squares. From the corresponding Fisher information matrix, we deduce an important insight, namely that longer degradation tests and longer intervals between measurements in the test design result in more precise parameter estimates. We introduce a model for optimizing the degradation test measurement plan that incorporates practical constraints and objectives in the test design framework. We also present a search‐based algorithm to identify the optimal test measurement plan that is based on the aforementioned measurement rule. Via a simulation study and a case study involving the Rubidium Atomic Frequency Standard, we demonstrate the characteristics of optimal measurement plans for bivariate degradation test design and show the superiority of longer duration tests involving fewer samples compared to alternative designs that specify testing more samples over shorter periods of time. Copyright © 2013 John Wiley & Sons, Ltd.
Gaseous byproducts from high‐temperature thermal conversion elemental analysis of nitrogen‐ and sulfur‐bearing compounds with considerations for δ2H and δ18O analyses
Authors: Hunsinger Glendon B. , Tipple Christopher A. , Stern Libby A.
Published: June 2013

RATIONALE

High‐temperature, conversion‐reduction (HTC) systems convert hydrogen and oxygen in materials into H2 and CO for δ2H and δ18O measurements by isotope ratio mass spectrometry. HTC of nitrogen‐ and sulfur‐bearing materials produces unintended byproduct gases that could affect isotope analyses by: (1) allowing isotope exchange reactions downstream of the HTC reactor, (2) creating isobaric or co‐elution interferences, and (3) causing deterioration of the chromatography. This study characterizes these HTC byproducts.

METHODS

A HTC system (ThermoFinnigan TC/EA) was directly connected to a gas chromatograph/quadrupole mass spectrometer in scan mode (m/z 8 to 88) to identify the volatile products generated by HTC at conversion temperatures of 1350 °C and 1450 °C for a range of nitrogen‐ and sulfur‐bearing solids [keratin powder, horse hair, caffeine, ammonium nitrate, potassium nitrate, ammonium sulfate, urea, and three nitrated organic explosives (PETN, RDX, and TNT)].

RESULTS

The prominent HTC byproduct gases include carbon dioxide, hydrogen cyanide, methane, acetylene, and water for all nitrogen‐bearing compounds, as well as carbon disulfide, carbonyl sulfide, and hydrogen sulfide for sulfur‐bearing compounds. The 1450 °C reactor temperature reduced the abundance of most byproduct gases, but increased the significant byproduct, hydrogen cyanide. Inclusion of a post‐reactor chemical trap containing Ascarite II and Sicapent, in series, eliminated the majority of byproducts.

CONCLUSIONS

This study identified numerous gaseous HTC byproducts. The potential adverse effects of these gases on isotope ratio analyses are unknown but may be mitigated by higher HTC reactor temperatures and purifying the products with a purge‐and‐trap system or with chemical traps. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.
Ultraviolet laser‐induced cross‐linking in peptides
Authors: Leo Gabriella , Altucci Carlo , Bourgoin‐Voillard Sandrine , Gravagnuolo Alfredo M. , Esposito Rosario , Marino Gennaro , Costello Catherine E. , Velotta Raffaele , Birolo Leila
Published: June 2013

RATIONALE

The aim of this study was to demonstrate, and to characterize by high‐resolution mass spectrometry that it is possible to preferentially induce covalent cross‐links in peptides by using high‐energy femtosecond ultraviolet (UV) laser pulses. The cross‐link is readily formed only when aromatic amino acids are present in the peptide sequence.

METHODS

Three peptides, xenopsin, angiotensin I, and interleukin, individually or in combination, were exposed to high‐energy femtosecond UV laser pulses, either alone or in the presence of spin trapping molecules, the reaction products being characterized by high resolution mass spectrometry.

RESULTS

High‐resolution mass spectrometry and spin trapping strategies showed that cross‐linking occurs readily, proceeds via a radical mechanism, and is the highly dominant reaction, proceeding without causing significant photo‐damage in the investigated range of experimental parameters.

CONCLUSIONS

High‐energy femtosecond UV laser pulses can be used to induce covalent cross‐links between aromatic amino acids in peptides, overcoming photo‐oxidation processes, that predominate as the mean laser pulse intensity approaches illumination conditions achievable with conventional UV light sources. Copyright © 2013 John Wiley & Sons, Ltd.
Laser ablation synthesis of new gold tellurides using tellurium and nanogold as precursors. Laser desorption ionisation time‐of‐flight mass spectrometry
Authors: Švihlová Katarína , Prokeš Lubomír , Skácelová Dana , Peña‐Méndez Eladia María , Havel Josef
Published: June 2013

RATIONALE

Only a few gold tellurides are known. However, Laser Ablation Synthesis (LAS) using Laser Desorption Ionisation (LDI) time‐of‐flight mass spectrometry (TOF MS) has high potential for the generation of new compounds.

METHODS

LDI of nanogold‐Te conjugate using a nitrogen laser 337 nm was applied while the mass spectra were recorded in positive and negative ion modes using a quadrupole ion trap‐TOF mass spectrometer equipped with a reflectron. Diffuse coplanar surface barrier discharge was applied for the plasma treatment of glass and silicon surfaces.

RESULTS

A form of nanogold‐Te conjugate was prepared and found suitable for LAS of gold tellurides. Several new AumTen (m = 1–11; n = 1–4) clusters were identified. An excess of nanogold and chloride or an excess of auric acid caused the formation of mixed AumTenClx clusters. The nanogold‐Te conjugate can be deposited from an aqueous suspension onto glass while the deposition is strongly enhanced if the surface is modified by plasma.

CONCLUSIONS

LDI of nanogold‐Te conjugate is a suitable procedure for the generation of new gold telluride clusters. Treatment of borosilicate glass with a diffuse coplanar surface barrier discharge strongly enhances the deposition of gold tellurides on glass while limited adsorption on a silicon surface was observed. Copyright © 2013 John Wiley & Sons, Ltd.
A clamped dual‐ridged waveguide measurement system for the broadband, nondestructive characterization of sheet materials
Authors: Hyde M. W. , Havrilla M. J.
Published: June 2013

A novel two‐port probe which uses dual‐ridged waveguides for the nondestructive, broadband characterization of sheet materials is presented. The new probe is shown to possess approximately 2 to 3 times the bandwidth of traditional coaxial and rectangular/circular waveguide probe systems while maintaining the structural robustness characteristic of rectangular/circular waveguide probe systems. The theoretical development of the probe is presented, namely, by applying Love's equivalence theorem and enforcing the continuity of transverse fields at the dual‐ridged waveguide apertures, a system of coupled magnetic field integral equations is derived. The system of coupled magnetic field integral equations is solved using the method of moments to yield theoretical expressions for the reflection and transmission coefficients. The complex permittivity and permeability of the unknown material under test are then found by minimizing the root‐mean‐square difference between the theoretical and measured reflection and transmission coefficients. Experimental results of two magnetic absorbing materials are presented to validate the new probe. The probe's sensitivity to measured scattering parameter, sample thickness, and flange‐plate thickness errors is also investigated.
Verifiable secret sharing based on the Chinese remainder theorem
Authors: Harn Lein , Fuyou Miao , Chang Chin‐Chen
Published: June 2013

A (t,n) secret sharing scheme (SS) enables a dealer to divide a secret into n shares in such a way that (i) the secret can be recovered successfully with t or more than t shares, and (ii) the secret cannot be recovered with fewer than t shares. A verifiable secret sharing scheme (VSS) has been proposed to allow shareholders to verify that their shares are generated by the dealer consistently without compromising the secrecy of both shares and the secret. So far, there is only one secure Chinese remainder theorem‐based VSS using the RSA assumption. We propose a Chinese remainder theorem‐based VSS scheme without making any computational assumptions, which is a simple extension of Azimuth–Bloom (t,n) SS. Just like the most well‐known Shamir's SS, the proposed VSS is unconditionally secure. We use a linear combination of both the secret and the verification secret to protect the secrecy of both the secret and shares in the verification. In addition, we show that no information is leaked when there are fewer than t shares in the secret reconstruction. Copyright © 2013 John Wiley & Sons, Ltd.
Research on hidden malicious user detection problem
Authors: Tingting Liu , Feng Shu
Published: June 2013

A method of detecting malicious user based on the enhanced Dempster‐Shafer (D‐S) algorithm for the hidden malicious user in cooperative spectrum sensing frame is proposed in this paper. The validity of this method is established by running simulations in the environment of hidden malicious user with different predefined probabilities. Compared with the original enhanced D‐S algorithm, the proposed method based on enhanced D‐S algorithm in this paper provides a better global sensing performance. Copyright © 2013 John Wiley & Sons, Ltd.
Fabrication of electroactive composite nanofibers of functionalized polymer and CNT capable of specifically binding with the IgE (Immunoglobulin E) antibody
Authors: Olubi Omotunde , Gadi Deepti , Sannigrahi Biswajit , Williams Michael , Baird Barbara , Khan Ishrat
Published: June 2013

Electroactive nanofibers decorated with α,ω‐bi‐(dinitrophenylcaproic acid), abbreviated as DNP, have been prepared by electrospinning a solution of α,ω‐bi[2,4‐dinitrophenylcaproic][poly(ethyleneoxide)‐b‐poly(2‐methoxystyrene)‐b‐poly(ethylene oxide)], polystyrene and single‐walled carbon nanotubes (SWCNTs). The α,ω‐bi[2,4‐dinitrophenylcaproic][poly(ethyleneoxide)‐b‐poly(2‐methoxystyrene)‐b‐poly(ethyleneoxide)] polymers were synthesized by living anionic polymerization and subsequent esterification to obtain the DNP‐functionalized polymers. The nanofibers (300 nm) were electrospun onto a silicon wafer substrate at a voltage of 10 kV using dimethylformamide and chlorobenzene as solvents. The nanofibers were characterized by Raman spectroscopy, fluorescence microscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM) and optical microscopy. The DNP groups, therein, were tethered to the nanofibers via oligo(oxyethylene) spacers. The DNP groups decorating the nanofibers were capable of specifically binding with anti‐DNP immunoglobulin E (IgE). The binding specificity of nanofibers containing 1% SWCNTs with anti‐DNP IgE was studied via fluorescently labeled (Fluorescein IsoThioCyanate) FITC‐IgE. Electronic activity of the nanofibers was studied by I–V plots from Kelvin sensing. The I–V plots before sensitizing with IgE differed from the I–V plots after binding with IgE. The results of the studies suggest the possibility of developing functional nanofibers as the active component in biosensors. Copyright © 2013 John Wiley & Sons, Ltd.
Sharp bounds on causal effects using a surrogate endpoint
Authors: Kuroki Manabu
Published: June 2013

This paper considers a problem of evaluating the causal effect of a treatment X on a true endpoint Y using a surrogate endpoint S, in the presence of unmeasured confounders between S and Y. Such confounders render the causal effect of X on Y unidentifiable from the causal effect of X on S and the joint probability of S and Y. To evaluate the causal effect of X on Y in such a situation, this paper derives closed‐form formulas for the sharp bounds on the causal effect of X on Y based on both the causal effect of X on S and the joint probability of S and Y under various assumptions. In addition, we show that it is not always necessary to observe Y to test the null causal effect of X on Y under the monotonicity assumption between X and S. These bounds enable clinical practitioners and researchers to assess the causal effect of a treatment on a true endpoint using a surrogate endpoint with minimum computational effort. Copyright © 2013 John Wiley & Sons, Ltd.
iDARE—a reference architecture for integrated software environments
Authors: Tajalli Hossein , Medvidović Nenad
Published: June 2013

Traditionally, software development environments have tended to treat a system's development‐time activities separately from its run‐time. After a system is in operation, it frequently needs to be maintained and evolved. In traditional environments, this results in frequent relocations of a system between the disjoint development and run‐time environments, which is undesirable for several reasons. A more effective solution is to couple the development and run‐time environments to directly monitor and adapt running systems. Given the growing need for interaction between development‐time and run‐time aspects of modern software systems, it is important to understand development and run‐time environments, and their relationship. To this end, we study and classify a wide range of software development environments on the basis of their level of interaction with the corresponding run‐time environments. Particularly, we identify, study, and characterize Self‐Adaptive Life‐cycle Environments (SALEs), an emerging class of modern development environments that are tightly integrated with run‐time environments. We reify our study of the development environments into a novel reference architecture, iDARE, that captures and differentiates the architectures of software environments – from those, such as traditional development environments, that have no interaction with the run‐time environments, to the ones, such as SALEs, that are tightly integrated with the run‐time environments. We use iDARE to highlight several shortcomings of existing SALEs. Adherence to iDARE has the potential to improve certain quality properties of the integrated development and run‐time environments, such as adaptability, fault‐tolerance, robustness, availability, and resource consumption. We identify a number of opportunities for future research. Copyright © 2013 John Wiley & Sons, Ltd.
Driving Force and Logic of Development of Advanced High Strength Steels for Automotive Applications
Authors: Bouaziz Olivier , Zurob Hatem , Huang Mingxin
Published: June 2013

The major scientific and technological advances and breakthroughs of advanced high strength steels (AHSS) were achieved due to the strong demands of automotive industry. The development of AHSS began in the early 1980s with the aim of improving passenger safety and weight‐saving. The present paper presents the driving forces and logic of development of various AHSS for automotive applications since 1980s. The importance of crash performance, weight‐saving, formability, and rigidity are critically reviewed for the development of new steel grades for automotive applications. The logical sequences of the development of dual phase (DP) steel, transformation induced plasticity (TRIP) steels, tempered DP steels, complex phases (CP) steels, Ferrite‐Bainite steels, hot‐stamping technology, twinning induced plasticity (TWIP) steels, Quench and Partitioning (Q&P) steels, Medium Mn steels, and steels–polymer composites are presented.
Getting Angry to Get Ahead: Black College Men, Emotional Performance, and Encouraging Respectable Masculinity
Authors: Jackson Brandon A. , Harvey Wingfield Adia
Published: June 2013

This article draws on two years of ethnographic fieldwork to explore how a group of black men on a college campus displayed anger in order to encourage other black men to adopt a respectable form of masculinity. Although prior research suggests that black men may work to avoid public displays of anger to evade negative stereotypes of black men, we uncover the contexts in which black men were comfortable expressing feelings of anger, frustration, annoyance, and irritation. Specifically, group leaders displayed these emotions when they observed recruits to their group engaging in actions or behaviors that threatened to reinforce certain stereotypes about black men.
Changes in participants' scientific attitudes and epistemological beliefs during an astronomical citizen science project
Authors: Price C. Aaron , Lee Hee‐Sun
Published: June 2013

Citizen science projects provide non‐scientists with opportunities to take part in scientific research. While their contribution to scientific data collection has been well documented, there is limited research on how participation in citizen science projects may affect their scientific literacy. In this study, we investigated (1) how volunteers' attitudes towards science and epistemological beliefs about the nature of science changed after six months of participation in an astronomy‐themed citizen science project and (2) how the level of project participation related to these changes. Two main instruments were used to measure participants' scientific attitude and epistemological beliefs and were administered before they registered for the program and six months after their registration. For analysis, we used pre‐ and post‐test data collected from 333 participants who responded to both tests. Among them, nine participants were randomly chosen for interviews. Participants' responses were analyzed using the Rasch Rating Scale Model. Results show that overall scientific attitudes changed positively, p < 0.01. The change was strongest in attitudes towards science news and citizen science projects. The scientific attitudinal change was related to participant social activity in the project. There was a negative change in their evaluation of their knowledge. The interviews suggest that this is due to a greater appreciation for what they have yet to learn. Epistemological beliefs about the nature of science significantly improved from the pre‐ to the post‐tests, p < 0.05. Overall, we found volunteers' participation in social components of the program was significantly related to their improvement in scientific literacy while other project participation variables (such as amount of data contributed to the project) was not. © 2013 Wiley Periodicals, Inc. J Res Sci Teach 50: 773–801, 2013
Firm and industry adaptation to climate change: a review of climate adaptation studies in the business and management field
Authors: Linnenluecke Martina K. , Griffiths Andrew , Winn Monika I.
Published: June 2013

Firms and industries will have a central role in supporting societal adaptation to the physical impacts of climate change, especially in more directly affected sectors such as agriculture, forestry, construction, or transportation. However, the business and management field has repeatedly been criticized for its lack of engagement with climate change as a pressing issue, and adaptation to the physical impacts of climate change in particular. Our review of adaptation studies in the business and management field suggests that most firm and industry adaptation studies focus on how firms adjust to changing business conditions because of the emergence of new competitors, new products, and markets or because of changed political, economic, and legal conditions; they largely exclude firm adjustments to the changing dynamics of the natural environment. Studies on firm and industry adaptation to climate impacts specifically are beginning to emerge, but they are sparse. There is still little cross‐disciplinary work integrating findings from the natural sciences into business thinking. We also find few considerations of the implications and consequences of climate change for firms and industries to date. This article provides an overview over the existing literature on firm adaptation to climate change, outlines research gaps, and suggests pathways for future research.WIREs Clim Change2013, 4:397–416. doi: 10.1002/wcc.214

This article is categorized under:

Vulnerability and Adaptation to Climate Change > Institutions for Adaptation
(Non-)commutative closed string on T-dual toroidal backgrounds
Authors: Andriot David , Larfors Magdalena , Lüst Dieter , Patalong Peter
Published: June 2013

Abstract

In this paper we investigate the connection between (non-)geometry and (non-)commutativity of the closed string. To this end, we solve the classical string on three T-dual toroidal backgrounds: a torus with H-flux, a twisted torus and a non-geometric background with Q-flux. In all three situations we work under the assumption of a dilute flux and consider quantities to linear order in the flux density. Furthermore, we perform the first steps of a canonical quantization for the twisted torus, to derive commutators of the string expansion modes. We use them as well as T-duality to determine, in the non-geometric background, a commutator of two string coordinates, which turns out to be non-vanishing. We relate this non-commutativity to the closed string boundary conditions, and the non-geometric Q-flux.
Synergism of α‐Linolenic Acid, Conjugated Linoleic Acid and Calcium in Decreasing Adipocyte and Increasing Osteoblast Cell Growth
Authors: Kim Youjin , Kelly Owen J. , Ilich Jasminka Z.
Published: June 2013

Whole fat milk and dairy products (although providing more energy compared to low‐ or non‐fat products), are good sources of α‐linolenic acid (ALA), conjugated linoleic acid (CLA) and calcium, which may be favorable in modulating bone and adipose tissue metabolism. We examined individual and/or synergistic effects of ALA, CLA and calcium (at levels similar to those in whole milk/dairy products) in regulating bone and adipose cell growth. ST2 stromal, MC3T3‐L1 adipocyte‐like and MC3T3‐E1 osteoblast‐like cells were treated with: (a) linoleic acid (LNA):ALA ratios = 1–5:1; (b) individual/combined 80–90 % c9, t11 (9,11) and 5–10 % t10, c12 (10,12) CLA isomers; (c) 0.5–3.0 mM calcium; (d) combinations of (a), (b), (c); and (e) control. Local mediators, including eicosanoids and growth factors, were measured. (a) The optimal effect was found at the 4:1 LNA:ALA ratio where insulin‐like growth factor‐1 (IGF‐1) and IGF binding protein‐3 (IGFBP‐3) production was the lowest in MC3T3‐L1 cells. (b) All CLA isomer blends decreased MC3T3‐L1 and increased MC3T3‐E1 cell differentiation. (c) 1.5–2.5 mM calcium increased ST2 and MC3T3‐E1, and decreased MC3T3‐L1 cell proliferation. (d) Combination of 4:1 LNA:ALA + 90:10 % CLA + 2.0 mM calcium lowered MC3T3‐L1 and increased MC3T3‐E1 cell differentiation. Overall, the optimal LNA:ALA ratio to enhance osteoblastogenesis and inhibit adipogenesis was 4:1. This effect was enhanced by 90:10 % CLA + 2.0 mM calcium, indicating possible synergism of these dietary factors in promoting osteoblast and inhibiting adipocyte differentiation in cell cultures.
Pharmacokinetics and biodistribution of negatively charged pectin nanoparticles encapsulating paclitaxel
Authors: Verma Anita K. , Kumar A.
Published: June 2013

Pectin, a naturally occurring biopolymer has been found to have increasing applications in the pharmaceutical and biotechnology industry. Sugars with their three-dimensional structures are important for many biological functions. We report preparation of negatively charged pectin nanoparticles encapsulating paclitaxel, a broad-spectrum anticancer drug for possible therapeutic applications. The mean diameter of the nanoparticles was ~300–350 nm with an encapsulation efficiency ~17 %. The TEM studies indicated that the particles were spherical in shape and their sizes are in unison with the DLS size spectra. The surface charge of pectin polymer was −5 mV and of nanoparticles were ~ −32 mV. The enhanced surface charge shows greater stability. The high electrophoretic mobility of ~3.5 to 1.5 μmcm/Vs confirmed the nano-size of particles. We compared the cytotoxic effect of paclitaxel (Pax) per se, pectin nanoparticles (PPN), and pectin chains on Hep G2, hepatic carcinoma cell line. Dose-dependent cytotoxicity was observed, wherein ~21.7 ± 3.2 % cytotoxicity was observed by PPN, but Pax per se showed ~55.6 ± 3.5 % cytotoxicity in a 72-h assay. The pharmacokinetics and biodistribution studies on Balb/c mice indicated that the nanoparticles had prolonged plasma retention of the drug with major accumulation in liver tissue after an i.v. tail vein injection of 20 mg/kg drug. The rank order of concentration are as follows, i.e., liver > kidney > lung > spleen for the PPN and spleen > liver > kidney ≥ lung for Pax per se. The in vitro studies clearly indicated that the efficacy of the drug was not compromised by encapsulation, making it a good candidate to deliver biopharmaceuticals. Nanoparticles produced free radicals in the free cell system and this ability caused oxidative stress, which may give rise to inflammation, cell destruction, and genotoxicity. Thus, the results obtained in this study holds great promise for pectin nanoparticles to be exploited for passive delivery of paclitaxel to tumor tissues, in particular, liver cancers.
At the boundary of the self: The insular cortex in patients with childhood‐onset schizophrenia, their healthy siblings, and normal volunteers
Authors: Moran Marcel E. , Weisinger Brian , Ludovici Katharine , McAdams Harrison , Greenstein Deanna , Gochman Pete , Miller Rachel , Clasen Liv , Rapoport Judith , Gogtay Nitin
Published: June 2013

The insular cortex (insula), whose normal function involves delineating the boundary between self and non‐self stimuli, has been implicated in the pathophysiology of the positive symptoms of schizophrenia, including hallucinations and delusions. Childhood‐onset schizophrenia (COS), that includes the onset of psychosis before age 13, is a severe and continuous form of the illness which shows profound and global progressive cortical brain abnormalities during adolescence which merge in the adult pattern with age. Using prospectively acquired anatomic brain magnetic resonance imaging (MRI) scans, a matched sample of COS patients, their nonpsychotic full siblings and healthy volunteers, we measured insular volume using the FreeSurfer automated software. COS patients (n = 98; 234 scans) had significantly lower right (p = 0.003), left (p < 0.001), and total (p < 0.001) insular volumes than healthy volunteers (n = 100; 248 scans). Right insular volume negatively correlated with positive symptoms as measured by the Scale for the Assessment of Positive Symptoms (SAPS) (p = 0.02), while both left (p = 0.01) and right (p = 0.006) insula volumes were positively correlated with overall functioning, as measured by the Children's Global Assessment Scale (CGAS) scores. COS siblings (n = 71; 153 scans), on the other hand, did not differ significantly from normal volunteers suggesting that the insular deficits are more related to the illness state than a familial endophenotype. These results also highlight the salience of the insula in positive symptoms of schizophrenia perhaps resulting from the inability to discriminate between self from the non‐self in COS. Further work to connect insular deficits to other neurocircuitries is warranted.
The classical hydraulic jump in a model of shear shallow-water flows
Authors: Richard G. L. , Gavrilyuk S. L.
Published: June 2013

A conservative hyperbolic two-parameter model of shear shallow-water flows is used to study the classical turbulent hydraulic jump. The parameters of the model, which are the wall enstrophy and the roller dissipation coefficient, are determined from measurements of the roller length and the deviation from the Bélanger equation of the sequent depth ratio (experimental data by Hager & Bremen,J. Hydraul. Res., vol. 27, 1989, pp. 565–585; and Hager, Bremen & Kawagoshi,J. Hydraul. Res., vol. 28, 1990, pp. 591–608). Stationary solutions to the model describe with a good accuracy the free-surface profile of the hydraulic jump. The model is also capable of predicting the oscillations of the jump toe. We show that if the upstream Froude number is larger than${\sim }1. 5$, the jump toe oscillates with a particular frequency, while for the Froude number smaller than 1.5 the solution becomes stationary. In particular, we show that for a given flow discharge, the oscillation frequency is a decreasing function of the Froude number.
Solitary waves in turbulent open-channel flow
Authors: Schneider Wilhelm
Published: June 2013

Two-dimensional turbulent free-surface flow is considered. The ensemble-averaged flow quantities may depend on time. The slope of the plane bottom of the channel is assumed to be small. The roughness of the bottom is allowed to vary with the space coordinate, leading to small variations in the bottom friction coefficient. An asymptotic analysis, which is free of turbulence modelling, is performed for large Reynolds numbers and Froude numbers close to the critical value 1. As a result, an extended Korteweg–deVries (KdV) equation for the surface elevation is obtained. Other flow quantities, such as pressure, flow velocity components, and bottom shear stress, are expressed in terms of the surface elevation. The steady-state version of the extended KdV equation has eigensolutions that describe stationary solitary waves. Time-dependent solutions of the extended KdV equation provide a means for discriminating between stable and unstable stationary solitary waves. Solutions of initial value problems show that there are transient solutions that approach asymptotically the stable stationary solitary wave, whereas other transient solutions decay asymptotically with increasing time.
Physical processes influencing acoustic radiation from jet engine inlets
Authors: Tam Christopher K. W. , Parrish Sarah A. , Envia Edmane , Chien Eugene W.
Published: June 2013

Numerical simulations of acoustic radiation from a jet engine inlet are performed using advanced computational aeroacoustics algorithms and high-quality numerical boundary treatments. As a model of modern commercial jet engine inlets, the inlet geometry of the NASA Source Diagnostic Test is used. Fan noise consists of tones and broadband sound. This investigation considers the radiation of tones associated with upstream-propagating duct modes. The primary objective is to identify the dominant physical processes that determine the directivity of the radiated sound. Two such processes have been identified. They are acoustic diffraction and refraction. Diffraction is the natural tendency for an acoustic duct mode to follow a curved solid surface as it propagates. Refraction is the turning of the direction of propagation of a duct mode by mean flow gradients. Parametric studies on the changes in the directivity of radiated sound due to variations in forward flight Mach number, duct mode frequency, azimuthal mode number and radial mode number are carried out. It is found there is a significant difference in directivity for the radiation of the same duct mode from an engine inlet when operating in static condition versus one in forward flight. It will be shown that the large change in directivity is the result of the combined effects of diffraction and refraction.
Two-dimensional magnetohydrodynamic turbulence in the limits of infinite and vanishing magnetic Prandtl number
Authors: Tran Chuong V. , Yu Xinwei , Blackbourn Luke A. K.
Published: June 2013

We study both theoretically and numerically two-dimensional magnetohydrodynamic turbulence at infinite and zero magnetic Prandtl number $\mathit{Pm}$ (and the limits thereof), with an emphasis on solution regularity. For $\mathit{Pm}= 0$, both $\Vert \omega \Vert ^{2} $ and $\Vert j\Vert ^{2} $, where $\omega $ and $j$ are, respectively, the vorticity and current, are uniformly bounded. Furthermore, $\Vert \boldsymbol{\nabla} j\Vert ^{2} $ is integrable over $[0, \infty )$. The uniform boundedness of $\Vert \omega \Vert ^{2} $ implies that in the presence of vanishingly small viscosity $\nu $ (i.e. in the limit $\mathit{Pm}\rightarrow 0$), the kinetic energy dissipation rate $\nu \Vert \omega \Vert ^{2} $ vanishes for all times $t$, including $t= \infty $. Furthermore, for sufficiently small $\mathit{Pm}$, this rate decreases linearly with $\mathit{Pm}$. This linear behaviour of $\nu \Vert \omega \Vert ^{2} $ is investigated and confirmed by high-resolution simulations with $\mathit{Pm}$ in the range $[1/ 64, 1] $. Several criteria for solution regularity are established and numerically tested. As $\mathit{Pm}$ is decreased from unity, the ratio $\Vert \omega \Vert _{\infty } / \Vert \omega \Vert $ is observed to increase relatively slowly. This, together with the integrability of $\Vert \boldsymbol{\nabla} j\Vert ^{2} $, suggests global regularity for $\mathit{Pm}= 0$. When $\mathit{Pm}= \infty $, global regularity is secured when either $\Vert \boldsymbol{\nabla} \boldsymbol{u}\Vert _{\infty } / \Vert \omega \Vert $, where $\boldsymbol{u}$ is the fluid velocity, or $\Vert j\Vert _{\infty } / \Vert j\Vert $ is bounded. The former is plausible given the presence of viscous effects for this case. Numerical results over the range $\mathit{Pm}\in [1, 64] $ show that $\Vert \boldsymbol{\nabla} \boldsymbol{u}\Vert _{\infty } / \Vert \omega \Vert $ varies slightly (with similar behaviour for $\Vert j\Vert _{\infty } / \Vert j\Vert $), thereby lending strong support for the possibility $\Vert \boldsymbol{\nabla} \boldsymbol{u}\Vert _{\infty } / \Vert \omega \Vert \lt \infty $ in the limit $\mathit{Pm}\rightarrow \infty $. The peak of the magnetic energy dissipation rate $\mu \Vert j\Vert ^{2} $ is observed to decrease rapidly as $\mathit{Pm}$ is increased. This result suggests the possibility $\Vert j\Vert ^{2} \lt \infty $ in the limit $\mathit{Pm}\rightarrow \infty $. We discuss further evidence for the boundedness of the ratios $\Vert \omega \Vert _{\infty } / \Vert \omega \Vert $, $\Vert \boldsymbol{\nabla} \boldsymbol{u}\Vert _{\infty } / \Vert \omega \Vert $ and $\Vert j\Vert _{\infty } / \Vert j\Vert $ in conjunction with observation on the density of filamentary structures in the vorticity, velocity gradient and current fields.
Electromagnetically driven zonal flows in a rapidly rotating spherical shell
Authors: Hollerbach Rainer , Wei Xing , Noir Jérõme , Jackson Andrew
Published: June 2013

We consider the flow of an electrically conducting fluid confined in a rotating spherical shell. The flow is driven by a directly imposed electromagnetic body force, created by the combination of an electric current flowing from the inner sphere to a ring-shaped electrode around the equator of the outer sphere and a separately imposed predominantly axial magnetic field. We begin by numerically computing the axisymmetric basic states, which consist of a strong zonal flow. We next compute the linear onset of non-axisymmetric instabilities, and fully three-dimensional solutions up to ten times supercritical. We demonstrate that an experimental liquid-sodium device 50 cm in diameter could achieve and exceed these parameter values.
Spreading and bistability of droplets on differentially heated substrates
Authors: Bostwick J. B.
Published: June 2013

An axisymmetric drop spreads on a radially heated, partially wetting solid substrate in a rotating geometry. The lubrication approximation is applied to the field equations for this thin viscous drop to yield an evolution equation that captures the dependence of viscosity, surface tension, gravity, centrifugal forces and thermocapillarity. We study the quasi-static spreading regime, whereby droplet motion is controlled by a constitutive law that relates the contact angle to the contact-line speed. Non-uniform heating of the substrate can generate both vertical and radial temperature gradients along the drop interface, which produce distinct thermocapillary forces and equivalently flows that affect the spreading process. For the non-rotating system, competition between surface chemistry (wetting) and thermocapillary flows induced by the thermal gradients gives rise to bistability in certain regions of parameter space in which the droplets converge to an equilibrium shape. The centrifugal forces that develop in a rotating geometry enlarge the bistability regions. Parameter regimes in which the droplet spreads indefinitely are identified and spreading laws are computed to compare with experimental results from the literature.
Emulsion flow through a packed bed with multiple drop breakup
Authors: Zinchenko Alexander Z. , Davis Robert H.
Published: June 2013

Pressure-driven squeezing of a concentrated emulsion of deformable drops through a randomly packed granular material is studied by rigorous three-dimensional multidrop–multiparticle simulations at low Reynolds numbers. The drops are comparable in size with granular particles, so the drop phase and the carrier fluid have different permeabilities, and the emulsion cannot be treated as single phase. Squeezing requires significant drop deformation and can meet much resistance, depending on the capillary number $\boldsymbol{Ca}$. The granular material is modelled as a random loose packing (RLP) of many highly-frictional rigid monodisperse spheres in a periodic cell in mechanical equilibrium. Flow simulations for many drops squeezing through the network of solid spheres are performed by an extension of the multipole-accelerated boundary-integral (BI) algorithm of Zinchenko & Davis (J. Comput. Phys., vol. 227, 2008, pp. 7841–7888). A major improvement is robust mesh control on drop surfaces combined with a novel fragmentation algorithm, now allowing for long-time simulations with intricate drop shapes and multiple breakups. A major challenge is that up to $O(1{0}^{5} )$ time steps are required in a simulation for time averaging, and $O(1{0}^{4} )$ boundary elements per surface to sufficiently resolve lubrication and breakups. Such simulations are feasible due to multipole acceleration, with two orders-of-magnitude gain over the standard BI coding. For initial drop-to-particle size ratio 0.51–0.52, emulsion concentration 41–42 % in the available space, and matching viscosities, time- and ensemble-averaged permeabilities of the drop phase and the continuous phase are studied versus $\boldsymbol{Ca}$ for systems of different size (up to 36 particles and 100 drops in a periodic cell). An avalanche of drop breakups observed at sufficiently large $\boldsymbol{Ca}$ does not preclude the permeabilities from reaching a statistical steady state in a feasible simulation time. The critical, system-size-independent $\boldsymbol{Ca}$, when the drop-phase flow effectively stops due to blockage in the pores by capillary forces, is estimated from simulations. For a sample RLP configuration, deep distinctions are found between the flow of concentrated emulsions and single-drop motion.
The dynamics of a non-dilute vesicle suspension in a simple shear flow
Authors: Zhao Hong , Shaqfeh Eric S. G.
Published: June 2013

We simulate multivesicle suspensions undergoing simple shear deformation by using the Stokes-flow boundary-integral equation method to quantify the effect of vesicle–vesicle interactions on the microstructure and rheology of the suspension. The binary collisions between vesicles are found to cause a vesicle’s instantaneous inclination angle to deviate considerably from its stationary tank-treading angle. The strength of the binary interaction becomes significant when the distance between centroids is less than three vesicle radii, which is consistent with observations from experiments. Vesicle interactions in the suspension delay the transition from tank-treading (TT) to trembling (TR)/tumbling (TU), which can be explained by the augmentation of the inclination angles in a binary collision when the viscosity ratio $\lambda $ is close to its critical value. Accordingly, in a non-dilute suspension the global minimum of the particle shear viscosity occurs at higher values of $\lambda $ due to the close correlation between the vesicle’s orientation and particle shear stress. In the high-$\lambda $ regime, collisions in a suspension disrupt the TU cycles of individual vesicles, resulting in intermittent TU/TR motions. In addition, an entangled state is observed to occur for an interacting vesicle pair in the TR/TU regime, where the centroids are aligned approximately parallel to the vorticity direction and rotates about it. The persistence of this close-range interaction results in two distinct peaks in the pair distribution of vesicles. However, their existence is limited to suspensions at low volume fraction, as they are otherwise disrupted by the three-body interactions that occur more frequently in a dense suspension.
WEAK CONTINUITY OF THE COMPLEX -HESSIAN OPERATORS WITH RESPECT TO LOCAL UNIFORM CONVERGENCE
Authors: TRUDINGER NEIL S. , ZHANG WEI
Published: June 2013

In this paper, we study the properties of $k$-plurisubharmonic functions defined on domains in ${ \mathbb{C} }^{n} $. By the monotonicity formula, we give an alternative proof of the weak continuity of complex $k$-Hessian operators with respect to local uniform convergence.
Up-regulation of endothelial nitric oxide synthase (eNOS), silent mating type information regulation 2 homologue 1 (SIRT1) and autophagy-related genes by repeated treatments with resveratrol in human umbilical vein endothelial cells
Authors: Takizawa Yoshie , Kosuge Yukiko , Awaji Hiroyo , Tamura Emi , Takai Ayako , Yanai Takaaki , Yamamoto Reiko , Kokame Koichi , Miyata Toshiyuki , Nakata Rieko , Inoue Hiroyasu
Published: June 2013

Resveratrol, a polyphenolic phytoalexin found in red wine and various plants, has been reported to up-regulate the expression of endothelial NO synthase (eNOS) in human umbilical vein endothelial cells (HUVEC). However, this effect was neither long term in nature nor physiologically relevant at the concentration of resveratrol studied. In the present study, we investigated the effects of repeated treatments with a lower concentration of resveratrol on the expression of genes in HUVEC. The expression levels of eNOS and silent mating type information regulation 2 homologue 1 (SIRT1) were up-regulated in HUVEC by repeated treatments with 1 μm-resveratrol for 6 d, but not with fenofibrate. Moreover, resveratrol treatment increased the expression of autophagy-regulated genes such as γ-aminobutyric acid A receptor-associated protein (GABARAP), microtubule-associated protein 1 light chain 3B (LC3B) and autophagy-related protein 3 (ATG3), the radical scavenger activity-related metallothionein-1X (MT1X) gene and the anti-inflammatory activity-related annexin A2 (ANXA) gene. In addition, resveratrol treatment down-regulated the expression of the cell-cycle checkpoint control RAD9 homologue B (RAD9B) gene. These results indicate the beneficial effects of resveratrol on the cardiovascular system.
U–Pb geochronology of Cretaceous magmatism on Svalbard and Franz Josef Land, Barents Sea Large Igneous Province
Authors: CORFU FERNANDO , POLTEAU STÉPHANE , PLANKE SVERRE , FALEIDE JAN INGE , SVENSEN HENRIK , ZAYONCHECK ANDREW , STOLBOV NIKOLAY
Published: June 2013

The opening of the Arctic oceanic basins in the Mesozoic and Cenozoic proceeded in steps, with episodes of magmatism and sedimentation marking specific stages in this development. In addition to the stratigraphic record provided by sediments and fossils, the intrusive and extrusive rocks yield important information on this evolution. This study has determined the ages of mafic sills and a felsic tuff in Svalbard and Franz Josef Land using the isotope dilution thermal ionization mass spectrometry (ID-TIMS) U–Pb method on zircon, baddeleyite, titanite and rutile. The results indicate crystallization of the Diabasodden sill at 124.5 ± 0.2 Ma and the Linnévatn sill at 124.7 ± 0.3 Ma, the latter also containing slightly younger secondary titanite with an age of 123.9 ± 0.3 Ma. A bentonite in the Helvetiafjellet Formation, also on Svalbard, has an age of 123.3 ± 0.2 Ma. Zircon in mafic sills intersected by drill cores in Franz Josef Land indicate an age of 122.7 Ma for a thick sill on Severnaya Island and a single grain age of ≥122.2 ± 1.1 Ma for a thinner sill on Nagurskaya Island. These data emphasize the importance and relatively short-lived nature of the Cretaceous magmatic event in the region.
Will Demographic Change Slow China's Rise?
Authors: Eggleston Karen , Oi Jean C. , Rozelle Scott , Sun Ang , Walder Andrew , Zhou Xueguang
Published: June 2013

China's 2010 census revealed a population of 1.34 billion, 50 percent urban, 13.3 percent above age sixty, and with 118.06 boys born for every 100 girls. In this article, we discuss how gender imbalance, population aging, and their interaction with rapid urbanization have shaped China's reform era development and will strongly shape China's future. These intertwined demographic changes pose an unprecedented challenge to social and economic governance, contributing to and magnifying the effects of a slower rate of economic growth. We organize the analysis according to the proximate determinants of economic growth: first, labor input and its productivity; second, capital investment and savings; and finally, multi-factor productivity, including social stability and governance. We argue that the economic, political, and social context that turns labor and capital inputs into economic outputs is perhaps the most important and least understood arena in which demographic change will shape China's rise.