bluuebunny/crossref_metadata_2025 huggingface dataset:
Behaviour of fatigue loaded self‐compacting concrete compared to vibrated concrete
Authors: Korte Sara , Boel Veerle , De Corte Wouter , De Schutter Geert
Published: June 2014

Fatigue loading and its sometimes inevitable fatigue failure are common in many civil engineering construction projects. The behaviour of vibrated concrete (VC) under this type of loading is well understood. However, the fracture and fatigue resistance of self‐compacting concrete (SCC) is poorly documented in literature. Considering the substantially different composition of the two concrete types (VC and SCC), it is uncertain whether their mechanical properties are similar or not. This paper describes the results of a series of destructive static and cyclic four‐point bending tests on inverted T‐shaped reinforced concrete beams, made from VC and SCC in equal quantities and of equal compressive strength. A comparison of the two concrete types is made, based on deflection, strain, crack width evolution and failure mechanism. The experiments prove that these mechanical properties of VC and SCC, subjected to a fatigue load, in some cases relate differently from a static loading process. Furthermore, the results reveal a faster concrete strain and crack width development for SCC during the fatigue tests. Regarding the number of cycles to failure, the applied load level is crucial.
Methylene blue adsorption from aqueous solutions to flexible poly(vinyl chloride) silica composites
Authors: Yetgin Senem , Ulutan Sevgi , Balkose Devrim
Published: June 2014

Methylene blue (MB) adsorption studies were performed with poly(vinyl chloride)‐(dioctyl phthalate)‐silica composites, which were obtained by using plastisol‐plastigel technology. The films were flexible, having elastic modulus of 1.0–1.5 GPa. Diminishing MB concentration in the aqueous phase was followed as the adsorption process advanced by using visible spectroscopy. Contributions of the individual components of the composites to adsorption were also investigated. Although the MB adsorption capacity was extensively high for silica, it was moderate for the composite, most likely owing to the occlusion of pores of silica by plasticizer to some extent. The improvement of MB adsorption capacity of the composites as the silica ratio increased was explicitly deduced from the optical microscopy photographs. The diffusion coefficients of MB through the composites were 5 × 10−13, 6 × 10−13, and 3 × 10−13 m2 s−1 with regression coefficients of 0.73, 0.89, and 0.88 for 0, 2, and 16% silica‐containing composites, respectively. Because of the slow diffusion of MB in poly(vinyl chloride)‐silica composites, using them as dynamic column adsorbent was not practical. However, these versatile plastics can be used as plastic labels, colored clothing, leather substitutes, antimicrobial medical devices, and laser printable surfaces. J. VINYL ADDIT. TECHNOL., 21:42–50, 2015. © 2014 Society of Plastics Engineers
The effect of crystallites on the rheological properties of microphase‐separated PVC‐PBA‐PVC triblock copolymers obtained by single electron transfer‐degenerative chain transfer living radical polymerization
Authors: Calafel I. , Muñoz M.E. , Santamaría A. , Boix M. , Conde J.I. , Pascual B.
Published: June 2014

Linear and nonlinear rheological properties of poly(vinyl chloride) (PVC)‐poly(n‐butyl acrylate)‐PVC triblocks of different compositions, obtained by single electron transfer‐degenerative chain transfer living radical polymerization, are investigated, focusing on the effect of crystallites. Dynamic mechanical thermal analysis results show the existence of two glass transition temperatures, denoting microphase segregation. However, rather than phase separation, it is the presence of two types of crystals that melt at Tm1 = 127 ± 0.8°C and Tm2 = 185 ± 2°C, respectively, the factor that determines the rheological response of the copolymers. To the difference with PVC homopolymers, extrusion flow measurements at very low temperatures (T = 100°C) are possible with the copolymers. A change in the viscosity‐temperature dependence is observed below and above the lowest melting temperature. Notwithstanding the microphase separation and the presence of crystallites, experiments carried out in conditions similar to industrial processing reveal a remarkable viscosity reduction for our copolymers with respect to PVC obtained by single electron transfer‐degenerative chain transfer living radical polymerization, conventional PVC, and PVC/[diethyl‐(2‐ethylhexyl) phthalate] compounds. Extrudates free of surface instabilities are obtained at low extrusion temperatures, such as 90–100°C. J. VINYL ADDIT. TECHNOL., 21:24–32, 2015. © 2014 Society of Plastics Engineers
The centrosome duplication cycle in health and disease
Authors: Nigg Erich A. , Čajánek Lukáš , Arquint Christian
Published: June 2014

Centrioles function in the assembly of centrosomes and cilia. Structural and numerical centrosome aberrations have long been implicated in cancer, and more recent genetic evidence directly links centrosomal proteins to the etiology of ciliopathies, dwarfism and microcephaly. To better understand these disease connections, it will be important to elucidate the biogenesis of centrioles as well as the controls that govern centriole duplication during the cell cycle. Moreover, it remains to be fully understood how these organelles organize a variety of dynamic microtubule‐based structures in response to different physiological conditions. In proliferating cells, centrosomes are crucial for the assembly of microtubule arrays, including mitotic spindles, whereas in quiescent cells centrioles function as basal bodies in the formation of ciliary axonemes. In this short review, we briefly introduce the key gene products required for centriole duplication. Then we discuss recent findings on the centriole duplication factor STIL that point to centrosome amplification as a potential root cause for primary microcephaly in humans. We also present recent data on the role of a disease‐related centriole‐associated protein complex, Cep164‐TTBK2, in ciliogenesis.
Human Pharyngeal Microbiome May Play A Protective Role in Respiratory Tract Infections
Authors: Gao Zhancheng , Kang Yu , Yu Jun , Ren Lufeng
Published: June 2014

The human pharyngeal microbiome, which resides at the juncture of digestive and respiratory tracts, may have an active role in the prevention of respiratory tract infections, similar to the actions of the intestinal microbiome against enteric infections. Recent studies have demonstrated that the pharyngeal microbiome comprises an abundance of bacterial species that interacts with the local epithelial and immune cells, and together, they form a unique micro-ecological system. Most of the microbial species in microbiomes are obligate symbionts constantly adapting to their unique surroundings. Indigenous commensal species are capable of both maintaining dominance and evoking host immune responses to eliminate invading species. Temporary damage to the pharyngeal microbiome due to the impaired local epithelia is also considered an important predisposing risk factor for infections. Therefore, reinforcement of microbiome homeostasis to prevent invasion of infection-prone species would provide a novel treatment strategy in addition to antibiotic treatment and vaccination. Hence continued research efforts on evaluating probiotic treatment and developing appropriate procedures are necessary to both prevent and treat respiratory infections.
Social‐cognitive, physiological, and neural mechanisms underlying emotion regulation impairments: understanding anxiety in autism spectrum disorder
Authors: White Susan W. , Mazefsky Carla A. , Dichter Gabriel S. , Chiu Pearl H. , Richey John A. , Ollendick Thomas H.
Published: June 2014

Anxiety is one of the most common clinical problems among children, adolescents, and adults with autism spectrum disorder (ASD), yet we know little about its etiology in the context of ASD. We posit that emotion regulation (ER) impairments are a risk factor for anxiety in ASD. Specifically, we propose that one reason why anxiety disorders are so frequently comorbid with ASD is because ER impairments are ubiquitous to ASD, stemming from socio‐cognitive, physiological, and neurological processes related to impaired cognitive control, regulatory processes, and arousal. In this review, we offer a developmental model of how ER impairments may arise in ASD, and when (moderating influences) and how (meditational mechanisms) they result in anxiety.
Association of fish oil supplement use with preservation of brain volume and cognitive function
Authors: Daiello Lori A. , Gongvatana Assawin , Dunsiger Shira , Cohen Ronald A. , Ott Brian R. ,   Alzheimer's Disease Neuroimaging Initiative
Published: June 2014

Objective

The aim of this study was to investigate whether the use of fish oil supplements (FOSs) is associated with concomitant reduction in cognitive decline and brain atrophy in older adults.

Methods

We conducted a retrospective cohort study to examine the relationship between FOS use during the Alzheimer's Disease Neuroimaging Initiative and indicators of cognitive decline. Older adults (229 cognitively normal individuals, 397 patients with mild cognitive impairment, and 193 patients with Alzheimer's disease) were assessed with neuropsychological tests and brain magnetic resonance imaging every 6 months. Primary outcomes included (1) global cognitive status and (2) cerebral cortex gray matter and hippocampus and ventricular volumes.

Results

FOS use during follow‐up was associated with significantly lower mean cognitive subscale of the Alzheimer's Disease Assessment Scale and higher Mini‐Mental State Examination scores among those with normal cognition. Associations between FOS use and the outcomes were observed only in APOE ε4–negative participants. FOS use during the study was also associated with less atrophy in one or more brain regions of interest.
Quasi-geostrophic approximation of anelastic convection
Authors: Busse Friedrich H. , Simitev Radostin D.
Published: June 2014

The onset of convection in a rotating cylindrical annulus with parallel ends filled with a compressible fluid is studied in the anelastic approximation. Thermal Rossby waves propagating in the azimuthal direction are found as solutions. The analogy to the case of Boussinesq convection in the presence of conical end surfaces of the annular region is emphasised. As in the latter case, the results can be applied as an approximation for the description of the onset of anelastic convection in rotating spherical fluid shells. Reasonable agreement with three-dimensional numerical results published by Jones, Kuzanyan & Mitchell (J. Fluid Mech., vol. 634, 2009, pp. 291–319) for the latter problem is found. As in those results, the location of the onset of convection shifts outwards from the tangent cylinder with increasing number $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}N_{\rho }$ of density scale heights until it reaches the equatorial boundary. A new result is that at a much higher number $N_{\rho }$ the onset location returns to the interior of the fluid shell.
Autonomy for ground-level robotic space exploration: framework, simulation, architecture, algorithms and experiments
Authors: Correal R. , Pajares G. , Ruz J. J.
Published: June 2014

Robotic surface planetary exploration is a challenging endeavor, with critical safety requirements and severe communication constraints. Autonomous navigation is one of the most crucial and yet risky aspects of these operations. Therefore, a certain level of local autonomy for onboard robots is an essential feature, so that they can make their own decisions independently of ground control, reducing operational costs and maximizing the scientific return of the mission. In addition, existing tools to support research in this domain are usually proprietary to space agencies, and out of reach of most researchers. This paper presents a framework developed to support research in this field, a modular onboard software architecture design and a series of algorithms that implement a visual-based autonomous navigation approach for robotic space exploration. It allows analysis of algorithms' performance and functional validation of approaches and autonomy strategies, data monitoring and the creation of simulation models to replicate the vehicle, sensors, terrain and operational conditions. The framework and algorithms are partly supported by open-source packages and tools. A set of experiments and field testing with a physical robot and hardware are described as well, detailing results and algorithms' processing time, which experience an incremented of one order of magnitude when executed in space-certified like hardware, with constrained resources, in comparison to using general purpose hardware.
The Infectious Intestinal Disease Study of England: A prospective evaluation of symptoms and health care use after an acute episode
Authors: CUMBERLAND P. , SETHI D. , RODERICK P. J. , WHEELER J. G. , COWDEN J. M. , ROBERTS J. A. , RODRIGUES L. C. , HUDSON M. J. , TOMPKINS D. S. ,   on behalf of the IID Study Executive
Published: June 2014

The sequelae of Infectious Intestinal Disease (IID) in a population-based sample of cases and matched controls were investigated for a period of 3 months following the initial infection. Incident cases of IID presenting to GPs or occurring in the community and controls were studied at 3 weeks and over a 3-month follow-up period. Cases were six times more likely than controls to have gastrointestinal symptoms, particularly diarrhoea, at 3 weeks. Ten per cent of cases consulted their GP in the 3 months after episode and 2·3% were referred to hospital. GP presentation rates were twice as high in cases. Gastrointestinal symptoms persist after IID, leading to an increased likelihood of GP consultation and hospital referral. Diagnosis of irritable bowel syndrome may be more likely following IID. The burden of IID is likely to be considerable given its high incidence and the frequency of such sequelae.
Petawatt laser absorption bounded
Authors: Levy Matthew C. , Wilks Scott C. , Tabak Max , Libby Stephen B. , Baring Matthew G.
Published: June 2014

The interaction of petawatt (1015 W) lasers with solid matter forms the basis for advanced scientific applications such as table-top particle accelerators, ultrafast imaging systems and laser fusion. Key metrics for these applications relate to absorption, yet conditions in this regime are so nonlinear that it is often impossible to know the fraction of absorbed light f, and even the range of f is unknown. Here using a relativistic Rankine-Hugoniot-like analysis, we show for the first time that f exhibits a theoretical maximum and minimum. These bounds constrain nonlinear absorption mechanisms across the petawatt regime, forbidding high absorption values at low laser power and low absorption values at high laser power. For applications needing to circumvent the absorption bounds, these results will accelerate a shift from solid targets, towards structured and multilayer targets, and lead the development of new materials.
Model‐Based Optimal Design and Execution of the First‐Inpatient Trial of the Anti‐IL‐6, Olokizumab
Authors: Kretsos K , Jullion A , Zamacona M , Harari O , Shaw S , Boulanger B , Oliver R
Published: June 2014

The first‐in‐patient study for olokizumab (OKZ) employed model‐based, optimal design and adaptive execution to define the concentration–C‐reactive protein (CRP) suppression response. Modeling and exploratory statistics activities involved: reverse engineering of first‐in‐class (tocilizumab) pharmacokinetic/pharmacodynamic (PK/PD) models, adaptation of models to OKZ with a priori knowledge and preclinical data translation, application of multidimensional Desirability Index for optimal study design, sample size reestimation based on new information, optimization of second study part via Bayesian analysis of interim data, and interim and final analysis for PK/PD objective attainment. Design work defined a dose window (0.1–3 mg/kg) for CRP suppression exploration and suggested 72 patients in five single‐dose levels would suffice. During execution, new information resulted in reestimating the study size to half. Halting the first part and conducting interim analysis for second part optimization followed. Second interim and final analyses confirmed attainment of study objective, illustrating efficiency and optimality of the study.

CPT Pharmacometrics Syst. Pharmacol. (2014) 3, e119; doi:10.1038/psp.2014.17; published online 18 June 2014
Nanogels for Drug Delivery: the Key Role of Nanogel–Drug Interactions
Authors: Ramos Jose , Pelaez-Fernandez Miguel , Forcada Jacqueline , Moncho-Jorda Arturo
Published: June 2014

Nanogels are cross-linked colloidal particles, which can swell by absorption (uptake) of large amounts of solvent, but they do not dissolve owing to the structure of the physically or chemically cross-linked polymeric network,. Micro-/nanogels exhibit a behaviour that extend from a polymeric solutions (swollen form) to hard particles (collapsed form). They can respond to physical stimuli (temperature, ionic strength, magnetic or electric fields, etc.), chemical stimuli (pH, ions, specific molecules, etc.) and biochemical stimuli (enzymatic substrates, affinity ligands, etc.). By changing the degree of swelling of the particles, effective nanogel–nanogel and nanogel–drug interactions can be reversibly tuned, giving rise to a wide range of possibilities.
Polymeric Micelles
Authors: Taboada P. , Barbosa S. , Concheiro A. , Alvarez-Lorenzo C.
Published: June 2014

Polymeric micelles are self-assemblies of amphiphilic polymers that exhibit greater thermodynamic and kinetic stability than micelles of classical surfactants. Block copolymers can be synthesized to bear a variety of chemical functionalities both in the hydrophobic and in the hydrophilic blocks, which allows the preparation of micelles with diverse structures and performances. The peculiar hydrophobic core–hydrophilic shell architecture of block copolymer assemblies in an aqueous medium has extended the applications of polymeric micelles to a large variety of fields, in particular addressing relevant needs in the biomedical field. The capability of polymeric micelles to encapsulate molecules in conjunction with their ability to accumulate in specific tissues or cells is being widely explored in the targeting of active substances. In this context, block copolymers that can sense external stimuli or internal variables are particularly suitable for the precise regulation of the site and the rate of drug delivery in the body. This chapter begins with a brief description of the procedures for synthesizing and characterizing block copolymers in order to introduce the reader to the mechanisms of micelle formation. Then, micellization of neutral, ionic and double hydrophilic block copolymers is covered in detail together with the techniques useful for characterizing the micellization process and the structure of the micelles. The last section is devoted to the pharmaceutical applications of micelles in drug solubilization, targeting, stimuli-responsive release and biological response modulation.
Dendrimers
Authors: Perisé-Barrios A. J. , Sepúlveda-Crespo D. , Shcharbin D. , Rasines B. , Gómez R. , Klajnert-Maculewicz B. , Bryszewska M. , de la Mata F. J. , Muñoz-Fernández M. A.
Published: June 2014

Dendrimers are polymeric macromolecules constituted of a repetitive sequence of monomers growing step-by-step from a multifunctional core in a radial iterative fashion, not by polymeric reactions. Their synthesis offers the opportunity to generate monodisperse, structure-controlled architectures resulting in utility in specific biomedical applications. Advances in the role of molecular weight and architecture on the behaviour of these dendrimers, together with recent progress in the design of biodegradable chemistries, has permitted the application of these branched polymers as antiviral drugs and in other applications outside medicine.
Analytical techniques for the chemical analysis of plant biomass and biomass products
Authors: Vaz Jr Sílvio
Published: June 2014

This critical review presents the state of the art for the chemical analysis of biomass and products from conversion processes.
Block copolymer self-assembly controlled by the “green” gas stimulus of carbon dioxide
Authors: Yan Qiang , Zhao Yue
Published: June 2014

CO2 can act as a “green” stimulus to precisely tune the self-assembly of block copolymers.
The Crystal-T algorithm: a new approach to calculate the SLE of lipidic mixtures presenting solid solutions
Authors: Maximo Guilherme J. , Costa Mariana C. , Meirelles Antonio J. A.
Published: June 2014

The Crystal-T algorithm accurately depicts the SLE phase diagrams of lipidic mixtures presenting solid solutions, measured in this work, by liquid and solid phase γ models.
Determining the molecular basis for the pH-dependent interaction between 2′-deoxynucleotides and 9H-pyrido[3,4-b]indole in its ground and electronic excited states
Authors: Gonzalez M. Micaela , Denofrio M. Paula , García Einschlag Fernando S. , Franca Carlos A. , Pis Diez Reinaldo , Erra-Balsells Rosa , Cabrerizo Franco M.
Published: June 2014

The nature of nucleotide and the pH modulate the type of complexes formed and the dynamic deactivation processes.
A bio-photoelectrochemical cell with a MoS3-modified silicon nanowire photocathode for hydrogen and electricity production
Authors: Zang Guo-Long , Sheng Guo-Ping , Shi Chen , Wang Yun-Kun , Li Wen-Wei , Yu Han-Qing
Published: June 2014

A bio-photoelectrochemical cell with a bioanode and a MoS3/SiNW photocathode is successfully constructed for hydrogen production under visible light illumination.
Characterization of a selective inhibitor for matrix metalloproteinase-8 (MMP-8)
Authors: Ding Derong , Lichtenwalter Katerina , Pi Hualiang , Mobashery Shahriar , Chang Mayland
Published: June 2014

MMP-8 has been implicated in various diseases using a reported selective MMP-8 inhibitor that is actually a broad-spectrum MMP inhibitor.
Synthesis of hybrid anticancer agents based on kinase and histone deacetylase inhibitors
Authors: Patel Hiren , Chuckowree Irina , Coxhead Peter , Guille Matthew , Wang Minghua , Zuckermann Alexandra , Williams Robin S. B. , Librizzi Mariangela , Paranal Ronald M. , Bradner James E. , Spencer John
Published: June 2014

A HDAC, kinase inhibitor hybrid, (Z)-N1-(3-((1H-pyrrol-2-yl)methylene)-2-oxoindolin-5-yl)-N8-hydroxyoctanediamide, 6, showed impressive anticancer action in a number of biochemical and cell-based assays.
Kinetic results for mutations of conserved residues H304 and R309 of human sulfite oxidase point to mechanistic complexities
Authors: Davis Amanda C. , Johnson-Winters Kayunta , Arnold Anna R. , Tollin Gordon , Enemark John H.
Published: June 2014

Several point mutations in the gene of human sulfite oxidase (hSO) result in isolated sulfite oxidase deficiency, an inherited metabolic disorder.
Modern multicomponent reactions for better drug syntheses
Authors: Zarganes-Tzitzikas Tryfon , Dömling Alexander
Published: June 2014

Multicomponent reaction (MCR) technology is now widely recognized for its impact on drug discovery projects and is strongly endorsed by industry as well as academia.
Effect of surface properties in protein corona development on mesoporous silica nanoparticles
Authors: Clemments Alden M. , Muniesa Carlos , Landry Christopher C. , Botella Pablo
Published: June 2014

The composition of the protein corona formed on mesoporous silica nanoparticles with several surface modifications was characterized.
Tribological investigations on β-lactam cephalosporin antibiotics as efficient ashless antiwear additives with low SAPS and their theoretical studies
Authors: Kalyani Kalyani , Jaiswal Vinay , Rastogi Rashmi B. , Kumar Devendra
Published: June 2014

The antiwear behavior of β-lactam cephalosporin antibiotics such as cefixime, cefadroxil and cephalexin has been studied using the Four Ball lubricant tester in paraffin oil.
Crocrassins A and B: two novel sesquiterpenoids with an unprecedented carbon skeleton from Croton crassifolius
Authors: Zhang Zhan-Xin , Li Hui-Hong , Qi Feng-Ming , Dong Le-Le , Hai Yang , Fan Gai-Xia , Fei Dong-Qing
Published: June 2014

Crocrassins A (1) and B (2), two novel sesquiterpenoids with a unique skeleton, were isolated from a Chinese medicinal plant Croton crassifolius.
MnO2nanoflakes grown on 3D graphite network for enhanced electrocapacitive performance
Authors: Sun Xiuxia , Wang Huanjing , Lei Zhibin , Liu Zonghuai , Wei Lingling
Published: June 2014

The highly conductive 3D graphite network prepared by CVD serves as an excellent skeleton to grow uniform MnO2nanoflakes with an enhanced capacitive performance.
Subtle backbone modifications control the interpenetration of dibenzosuberone-based coordination cages
Authors: Schulte Thorben R. , Krick Marcel , Asche Carmen I. , Freye Sabrina , Clever Guido H.
Published: June 2014

The self-assembly of interpenetrated double-cages was examined with respect to various synthetic modifications of the dibenzosuberone backbone.
Speciation and decomposition pathways of ruthenium catalysts used for selective C–H hydroxylation
Authors: Flender Cornelia , Adams Ashley M. , Roizen Jennifer L. , McNeill Eric , Du Bois J. , Zare Richard N.
Published: June 2014

Mechanistic insight into the C–H hydroxylation reaction catalysed by [(Me3tacn)RuCl3] has been obtained using desorption electrospray ionization mass spectrometry (DESI-MS) to identify reactive intermediates and to determine the fate of the starting metal complex.
Charge transfer interactions in self-assembled single walled carbon nanotubes/Dawson–Wells polyoxometalate hybrids
Authors: Bosch-Navarro Concha , Matt Benjamin , Izzet Guillaume , Romero-Nieto Carlos , Dirian Konstantin , Raya Andrés , Molina Sergio I. , Proust Anna , Guldi Dirk M. , Martí-Gastaldo Carlos , Coronado Eugenio
Published: June 2014

Electron transfer in strongly coupled photoactive hybrids built by direct combination of Dawson-type polyoxometalates with pyrene anchors and SWCNTs.
Selective recognition of fluoride anion in water by a copper(ii) center embedded in a hydrophobic cavity
Authors: Brugnara Andrea , Topić Filip , Rissanen Kari , Lande Aurélien de la , Colasson Benoit , Reinaud Olivia
Published: June 2014

CuII coordination combined with hydrophobic pocket hosting allows for strong and selective fluoride binding in water at near neutral pH.
Cu(ii) nanocluster-grafted, Nb-doped TiO2 as an efficient visible-light-sensitive photocatalyst based on energy-level matching between surface and bulk states
Authors: Liu Min , Qiu Xiaoqing , Hashimoto Kazuhito , Miyauchi Masahiro
Published: June 2014

Efficient visible-light-sensitive TiO2 photocatalysts were developed based on the energy level matching between surface-grafted Cu(ii) nanoclusters and bulk-doped Nb ions.
A 3D hybrid of layered MoS2/nitrogen-doped graphene nanosheet aerogels: an effective catalyst for hydrogen evolution in microbial electrolysis cells
Authors: Hou Yang , Zhang Bo , Wen Zhenhai , Cui Shumao , Guo Xiaoru , He Zhen , Chen Junhong
Published: June 2014

A novel 3D hybrid of layered MoS2/nitrogen-doped graphene nanosheet aerogels exhibits significantly enhanced catalytic activity for bio-electrochemical hydrogen evolution.
A novel zwitterionic bioceramic with dual antibacterial capability
Authors: Colilla Montserrat , Martínez-Carmona Marina , Sánchez-Salcedo Sandra , Ruiz-González M. Luisa , González-Calbet José M. , Vallet-Regí María
Published: June 2014

A novelzwitterionicbioceramic is developed, capable of lowering the relative bacterial adhesion from 100% to below 0.1%, as derived fromin vitroassays usingS. aureus. This matrix can release antibiotics over a long time and provides new insights in the treatment of bone implant infections.
Robust neural network‐based control of static var compensator
Authors: Chang Yeong‐Chan
Published: June 2014

This study addresses the problem of designing robust stabilisation control for a large class of uncertain single‐machine infinite‐bus electrical power systems with static var compensator (SVC). This class of systems may be perturbed by plant uncertainties, unmodelled perturbations and external disturbances. An adaptive neural network‐based dynamic feedback controller is developed such that all the states and signals of the closed‐loop system are bounded and the stabilisation error can be made as small as possible. As the small perturbations in the input weighting gains are neglected, an H∞ control performance can be guaranteed. The adaptive neural network approximation systems are designed to learn the behaviours of the unknown functions, and in turn a modified procedure is proposed such that the number of the neural network basis functions can be significantly reduced. Consequently, the intelligent robust control scheme developed here possesses the properties of computational simplicity and easy implementation from the viewpoint of practical applications. The developed robust control scheme not only can handle a large class of uncertain SVC‐driven power systems, but also achieve the aim of enhancing the stability performance. Finally, simulations are provided to demonstrate the effectiveness and performance of the proposed control algorithm.
Pressure-assisted fabrication of organic light emitting diodes with MoO3 hole-injection layer materials
Authors: Du J. , Anye V. C. , Vodah E. O. , Tong T. , Zebaze Kana M. G. , Soboyejo W. O.
Published: June 2014

In this study, pressures of ∼5 to ∼8 MPa were applied to organic light emitting diodes containing either evaporated molybdenum trioxide (MoO3) or spin-coated poly(3,4-ethylene dioxythiophene) doped with poly(styrene sulphonate) (PEDOT:PSS) hole-injection layers (HILs). The threshold voltages for both devices were reduced by about half, after the application of pressure. Furthermore, in an effort to understand the effects of pressure treatment, finite element simulations were used to study the evolution of surface contact between the HIL and emissive layer (EML) under pressure. The blister area due to interfacial impurities was also calculated. This was shown to reduce by about half, when the applied pressures were between ∼5 and 8 MPa. The finite element simulations used Young's modulus measurements of MoO3 that were measured using the nanoindentation technique. They also incorporated measurements of the adhesion energy between the HIL and EML (measured by force microscopy during atomic force microscopy). Within a fracture mechanics framework, the implications of the results are then discussed for the pressure-assisted fabrication of robust organic electronic devices.
D magnetism in Ca doped narrow carbon nanotubes: First principle chirality effect study
Authors: Hajiheidari F. , Khoshnevisan B. , Hashemifar S. J.
Published: June 2014

Curvature has always had crucial effects on the physical properties of narrow carbon nanotubes (CNTs) and here spin-polarized density functional calculations were employed to study electronic and magnetic properties of calcium-decorated narrow (5,5) and (9,0)CNTs with close diameters (∼7 Å) and different chiralities. Our results showed that chirality had great impact on the electronic structure and magnetization of the doped CNTs. In addition, internally or externally doping of the calcium atoms was studied comparatively and although for the (9,0)CNT the internal doping was the most stable configuration, which involves a novel kind of spin-polarization originated from Ca-4s electrons, but for the (5,5)tube the external doping was the most stable one without any spin-polarization. On the other hand, calcium doping in the center of the (5,5)CNT was an endothermic process and led to the spin-polarization of unoccupied Ca-3d orbitals via direct exchange interaction between adjacent Ca atoms. In the considered systems, the existence of magnetization in the absence of any transition-metal elements was an example of valuable d0 magnetism title.
Modified Lennard-Jones model: Virial coefficients to the 7th order
Authors: Ushcats M. V.
Published: June 2014

The modified Lennard-Jones potential, which simplifies the numerical simulations and maintains the realistic behavior of its parent, is proposed to a role of the standard interaction model for both the experimental and theoretical studies. The virial coefficients of this model up to the seventh order have been calculated for the range of temperatures kT/ɛ = 0.3–70. In the computations, a technique has been used, that combines the quadrature integration and Mayer Sampling Monte Carlo method (MSMC). Unlike the original MSMC, this technique does not require the reference coefficients of another potential and can be used in a wide range of temperatures for various interaction models.
Explicit correlation treatment of the potential energy surface of CO2 dimer
Authors: Kalugina Yulia N. , Buryak Ilya A. , Ajili Yosra , Vigasin Andrei A. , Jaidane Nejm Eddine , Hochlaf Majdi
Published: June 2014

We present an extensive study of the four-dimensional potential energy surface (4D-PES) of the carbon dioxide dimer, (CO2)2. This PES is developed over the set of intermolecular coordinates. The electronic computations are carried out at the explicitly correlated coupled cluster method with single, double, and perturbative triple excitations [CCSD(T)-F12] level of theory in connection with the augmented correlation-consistent aug-cc-pVTZ basis set. An analytic representation of the 4D-PES is derived. Our extensive calculations confirm that “Slipped Parallel” is the most stable form and that the T-shaped structure corresponds to a transition state. Later on, this PES is employed for the calculations of the vibrational energy levels of the dimer. Moreover, the temperature dependence of the dimer second virial coefficient and of the first spectral moment of rototranslational collision-induced absorption spectrum is derived. For both quantities, a good agreement is found between our values and the experimental data for a wide range of temperatures. This attests to the high quality of our PES. Generally, our PES and results can be used for modeling CO2 supercritical fluidity and examination of its role in planetary atmospheres. It can be also incorporated into dynamical computations of CO2 capture and sequestration. This allows deep understanding, at the microscopic level, of these processes.
Structure and tunneling dynamics in a model system of peptide co-solvents: Rotational spectroscopy of the 2,2,2-trifluoroethanol⋯water complex
Authors: Thomas Javix , Xu Yunjie
Published: June 2014

The hydrogen-bonding topology and tunneling dynamics of the binary adduct, 2,2,2-trifluoroethanol (TFE)⋯water, were investigated using chirped pulse and cavity based Fourier transform microwave spectroscopy with the aid of high level ab initio calculations. Rotational spectra of the most stable binary TFE⋯water conformer and five of its deuterium isotopologues were assigned. A strong preference for the insertion binding topology where water is inserted into the existing intramolecular hydrogen-bonded ring of TFE was observed. Tunneling splittings were detected in all of the measured rotational transitions of TFE⋯water. Based on the relative intensity of the two tunneling components and additional isotopic data, the splitting can be unambiguously attributed to the tunneling motion of the water subunit, i.e., the interchange of the bonded and nonbonded hydrogen atoms of water. The absence of any other splitting in the rotational transitions of all isotopologues observed indicates that the tunneling between g+ and g− TFE is quenched in the TFE⋯H2O complex.
Electronic transport and conduction mechanism transition in La1∕3Sr2∕3FeO3 thin films
Authors: Devlin R. C. , Krick A. L. , Sichel-Tissot R. J. , Xie Y. J. , May S. J.
Published: June 2014

We report on the electronic transport properties of epitaxial La1∕3Sr2∕3FeO3 films using temperature dependent resistivity, Hall effect, and magnetoresistance measurements. We show that the electronic phase transition, which occurs near 190 K, results in a change in conduction mechanism from nonadiabatic polaron transport at high temperatures to resistivity behavior following a power law temperature dependence at low temperatures. The phase transition is also accompanied by an abrupt increase in apparent mobility and Hall coefficient below the critical temperature (T*). We argue that the exotic low temperature transport properties are a consequence of the unusually long-range periodicity of the antiferromagnetic ordering, which also couples to the electronic transport in the form of a negative magnetoresistance below T* and a sign reversal of the Hall coefficient at T*. By comparing films of differing thicknesses, stoichiometry, and strain states, we demonstrate that the observed conduction behavior is a robust feature of La1∕3Sr2∕3FeO3.
Low energy ion distribution measurements in Madison Symmetric Torus plasmas
Authors: Titus J. B. , Mezonlin E. D. , Johnson J. A.
Published: June 2014

Charge-exchange neutrals contain information about the contents of a plasma and can be detected as they escape confinement. The Florida A&M University compact neutral particle analyzer (CNPA), used to measure the contents of neutral particle flux, has been reconfigured, calibrated, and installed on the Madison Symmetric Torus (MST) for high temperature deuterium plasmas. The energy range of the CNPA has been extended to cover 0.34–5.2 keV through an upgrade of the 25 detection channels. The CNPA has been used on all types of MST plasmas at a rate of 20 kHz throughout the entire discharge (∼70 ms). Plasma parameter scans show that the ion distribution is most dependent on the plasma current. Magnetic reconnection events throughout these scans produce stronger poloidal electric fields, stronger global magnetic modes, and larger changes in magnetic energy all of which heavily influence the non-Maxwellian part of the ion distribution (the fast ion tail).
Electronic properties of polycrystalline graphene under large local strain
Authors: He Xin , Gao Li , Tang Ning , Duan Junxi , Mei Fuhong , Meng Hu , Lu Fangchao , Xu Fujun , Wang Xinqiang , Yang Xuelin , Ge Weikun , Shen Bo
Published: June 2014

To explore the transport properties of polycrystalline graphene under large tensile strain, a strain device has been fabricated using piezocrystal to load local strain onto graphene, up to 22.5%. Ionic liquid gate whose capability of tuning carrier density being much higher than that of a solid gate is used to survey the transfer characteristics of the deformed graphene. The conductance of the Dirac point and field effect mobility of electrons and holes is found to decrease with increasing strain, which is attributed to the scattering of the graphene grain boundaries, the strain induced change of band structure, and defects. However, the transport gap is still not opened. Our study is helpful to evaluate the application of graphene in stretchable electronics.
Structural dynamics of cisplatin binding to histidine in a protein
Authors: Tanley Simon W. M. , Helliwell John R.
Published: June 2014

The platinum anti-cancer agents cisplatin and carboplatin bind to the histidine 15 residue in the model protein hen egg white lysozyme. By using temperatures either side of the protein glass transition state (∼180 K), several platinum binding modes are seen and show that not all these platinum modes are stable. In particular, the mean square displacement vibration amplitudes of the cisplatin and of the histidine to which it is bound are analysed in detail. As well as the multiple platinum peaks, the electron density for the His-15 side chain is weak to absent at 150 K and 200 K, which points to the imidazole ring of the His side chain sampling multiple positions. Most interestingly, the His-15 imidazole becomes more ordered at room temperature.
Reactive ion etching-assisted surface-enhanced Raman scattering measurements on the single nanoparticle level
Authors: Wang Si-Yi , Jiang Xiang-Xu , Xu Ting-Ting , Wei Xin-Pan , Lee Shuit-Tong , He Yao
Published: June 2014

Single-nanoparticle surface-enhanced Raman scattering (SERS) measurement is of essential importance for both fundamental research and practical applications. In this work, we develop a class of single-particle SERS approaches, i.e., reactive ion etching (RIE)-assisted SERS measurements correlated with scanning electron microscopy (SEM) strategy (RIE/SERS/SEM), enabling precise and high-resolution identification of single gold nanoparticle (AuNP) in facile and reliable manners. By using AuNP-coated silicon wafer and quartz glass slide as models, we further employ the developed RIE/SERS/SEM method for interrogating the relationship between SERS substrates and enhancement factor (EF) on the single particle level. Together with theoretical calculation using an established finite-difference-time-domain (FDTD) method, we demonstrate silicon wafer as superior SERS substrates, facilitating improvement of EF values.
Modeling and validation of autoinducer-mediated bacterial gene expression in microfluidic environments
Authors: Austin Caitlin M. , Stoy William , Su Peter , Harber Marie C. , Bardill J. Patrick , Hammer Brian K. , Forest Craig R.
Published: June 2014

Biosensors exploiting communication within genetically engineered bacteria are becoming increasingly important for monitoring environmental changes. Currently, there are a variety of mathematical models for understanding and predicting how genetically engineered bacteria respond to molecular stimuli in these environments, but as sensors have miniaturized towards microfluidics and are subjected to complex time-varying inputs, the shortcomings of these models have become apparent. The effects of microfluidic environments such as low oxygen concentration, increased biofilm encapsulation, diffusion limited molecular distribution, and higher population densities strongly affect rate constants for gene expression not accounted for in previous models. We report a mathematical model that accurately predicts the biological response of the autoinducer N-acyl homoserine lactone-mediated green fluorescent protein expression in reporter bacteria in microfluidic environments by accommodating these rate constants. This generalized mass action model considers a chain of biomolecular events from input autoinducer chemical to fluorescent protein expression through a series of six chemical species. We have validated this model against experimental data from our own apparatus as well as prior published experimental results. Results indicate accurate prediction of dynamics (e.g., 14% peak time error from a pulse input) and with reduced mean-squared error with pulse or step inputs for a range of concentrations (10 μM–30 μM). This model can help advance the design of genetically engineered bacteria sensors and molecular communication devices.
The Cités Strike Back: Restive Responses to Territorial Taint in the French Banlieues
Authors: Kirkness Paul
Published: June 2014

Territorial stigmatisation in France is produced and enacted through a wide range of agencies: the media, political and policy discourses, academic debates on the alleged ‘ghettoisation’ of French outer city, and the official ‘urban policy’ of the central government. This paper departs from research seeking to analyse the production and diffusion of these disparaging images by focusing on the perspective and reactions of the bearers of the stigma. Drawing on 18 months of field observation in two defamed housing estates in Nîmes, in Southern France, I question the thesis of the wholesale internalisation of negative representations by residents of the banlieues. I propose instead that their perceptions of stigma are deeply ambivalent, as evidenced by their abiding attachment to place. Mindful of the danger of romanticising the subaltern, I argue that many transgressions of the norms of dominant society are ways of deflecting and displacing the language of spatial stigma.
Territorial Stigmatization in Action
Authors: Wacquant Loïc , Slater Tom , Pereira Virgílio Borges
Published: June 2014

This theme issue of Environment and Planning A builds on the analytic framework elaborated by Wacquant in Urban Outcasts (Polity Press, 2008) and on the activities of the Leverhulme Network on Advanced Urban Marginality to synthesize and stimulate inquiries into the triadic nexus of symbolic space, social space, and physical space at the lower end of the urban spectrum. The concept of territorial stigmatization weds with Bourdieu's theory of ‘symbolic power’ Goffman's model of the management of ‘spoiled identity’ to capture how the blemish of place impacts the residents of disparaged districts, the surrounding denizens and commercial operators, street-level public bureaucracies, specialists in cultural production (such as journalists, scholars, and politicians), and state officials and policies. Spatial taint is a novel and distinctive phenomenon that crystallized at century's end along with the dissolution of the neighborhoods of relegation emblematic of the Fordist–Keynesian phase of industrial capitalism. It differs from the traditional topography of disrepute in the industrial city in that it has become autonomized, nationalized and democratized, equated with social disintegration, racialized through selective accentuation, and it elicits revulsion often leading to punitive corrective measures. The sociosymbolic strategies fashioned by the residents of defamed quarters to cope with spatial denigration span a panoply ranging from submission to defiance, and their adoption depends on position and trajectory in social and physical space. Territorial stigmatization is not a static condition or a neutral process, but a consequential and injurious form of action through collective representation fastened on place. By probing how it operates in different urban settings and political formations, the contributors to this issue advance our empirical understanding of the role of symbolic structures in the production of inequality and marginality in the city. They also suggest the need for public policies designed to reduce, not only the burden of material deprivation, but also the press of symbolic domination in the metropolis.
Integrating Environmental Justice and Socioecological Models of Health to Understand Population-Level Physical Activity
Authors: Shortt Niamh K , Rind Esther , Pearce Jamie , Mitchell Richard
Published: June 2014

The uneven geographical distribution of environmental pathogens and salutogens, as well as the political, social, and cultural antecedents leading to this sociospatial arrangement, have been posited as a partial explanation for the stark inequalities in health across many high-income nations. Whilst there is significant international evidence for the maldistribution of health-related environmental features, few studies have examined the material outcomes (including health) of this unequal environmental ‘exposure’. In this paper we utilise the theoretical stances offered by work in the fields of environmental justice and socioecological models of health to consider the pathway between physical environmental deprivation and health. We consider the influence of multiple aspects of the ‘natural’ physical environment on individual-level levels of physical activity—both utilitarian and physical activity for leisure. We found that, for physical activity conducted for recreational purposes, there is a strong relationship with the natural physical environment: those living in the least deprived physical environments are most likely to engage in physical activity. However, for utilitarian physical activity, physical activity whose primary purpose is not the activity itself, we observed increased levels in the most environmentally deprived areas. Finally, the important role that the environment may play in shaping capabilities, particularly during the current economic and political climate, is recognised. Our results show that the environment matters and that rhetoric regarding ‘lifestyle choice’ needs to be viewed in a broader environmental context.