bluuebunny/crossref_metadata_2025 huggingface dataset:
A direct numerical simulation study of vorticity transformation in weakly turbulent premixed flames
Authors: Lipatnikov A. N. , Nishiki S. , Hasegawa T.
Published: October 2014

Database obtained earlier in 3D Direct Numerical Simulations (DNS) of statistically stationary, 1D, planar turbulent flames characterized by three different density ratios σ is processed in order to investigate vorticity transformation in premixed combustion under conditions of moderately weak turbulence (rms turbulent velocity and laminar flame speed are roughly equal to one another). In cases H and M characterized by σ = 7.53 and 5.0, respectively, anisotropic generation of vorticity within the flame brush is reported. In order to study physical mechanisms that control this phenomenon, various terms in vorticity and enstrophy balance equations are analyzed, with both mean terms and terms conditioned on a particular value c of the combustion progress variable being addressed. Results indicate an important role played by baroclinic torque and dilatation in transformation of average vorticity and enstrophy within both flamelets and flame brush. Besides these widely recognized physical mechanisms, two other effects are documented. First, viscous stresses redistribute enstrophy within flamelets, but play a minor role in the balance of the mean enstrophy \documentclass[12pt]{minimal}\begin{document}$\overline{\Omega }$\end{document}Ω¯ within turbulent flame brush. Second, negative correlation \documentclass[12pt]{minimal}\begin{document}$\overline{\mathbf {u}^{\prime } \cdot \nabla \Omega ^{\prime }}$\end{document}u′·∇Ω′¯ between fluctuations in velocity u and enstrophy gradient contributes substantially to an increase in the mean \documentclass[12pt]{minimal}\begin{document}$\overline{\Omega }$\end{document}Ω¯ within turbulent flame brush. This negative correlation is mainly controlled by the positive correlation between fluctuations in the enstrophy and dilatation and, therefore, dilatation fluctuations substantially reduce the damping effect of the mean dilatation on the vorticity and enstrophy fields. In case L characterized by σ = 2.5, these effects are weakly pronounced and \documentclass[12pt]{minimal}\begin{document}$\overline{\Omega }$\end{document}Ω¯ is reduced mainly due to viscosity. Under conditions of the present DNS, vortex stretching plays a minor role in the balance of vorticity and enstrophy within turbulent flame brush in all three cases.
Spin decoherence in n-type GaAs: The effectiveness of the third-body rejection method for electron-electron scattering
Authors: Marchetti Gionni , Hodgson Matthew , D'Amico Irene
Published: October 2014

We study the spin decoherence in n-type bulk GaAs for moderate electronic densities at room temperature using the Ensemble Monte Carlo method. We demonstrate that a technique called “third-body rejection method” devised by B. K. Ridley, J. Phys. C: Solid State Phys. 10, 1589 (1977) can be successfully adapted to Ensemble Monte Carlo method and used to tackle the problem of the electron-electron contribution to spin decoherence in the parameter region under study, where the electron-electron interaction can be reasonably described by a Yukawa potential. This scattering technique is employed in a doping region where one can expect that multiple collisions may play a role in carrier dynamics. By this technique, we are able to calculate spin relaxation times which are in very good agreement with the experimental results found by Oertel et al., Appl. Phys. Lett. 93, 13 (2008). Through this method, we show that the electron-electron scattering is overestimated in Born approximation, in agreement with previous results obtained by C. A. Kukkonen and H. Smith, Phys. Rev. B 8, 4601 (1973).
Selective normal mode excitation in multilayer thin film bulk acoustic wave resonators
Authors: Kozyrev Andrey , Mikhailov Anatoly , Ptashnik Sergey , Petrov Peter K. , Alford Neil
Published: October 2014

A method for selective normal mode excitation in thin film bulk acoustic wave resonators, based on multilayer structures with any number of ferroelectric films in the paraelectric phase, is presented. The possibility to control the excitation of thin film bulk acoustic resonators' normal modes by simultaneous manipulating both the polarities and the magnitudes of the dc bias voltages applied to the ferroelectric layers is demonstrated. The proposed method was verified using the Lakin's model, modified to describe the electro-mechanical behavior of a structure with four active ferroelectric layers.
Novel conducting polymer current limiting devices for low cost surge protection applications
Authors: Jabarullah Noor H. , Verrelli Emanuele , Mauldin Clayton , Navarro Luis A. , Golden Josh , Madianos Leonidas , Tsoukalas Dimitris , Kemp Neil T.
Published: October 2014

We report on the development of novel intrinsic conducting polymer two terminal surge protection devices. These resettable current limiting devices consist of polyaniline nanofibres doped with methane sulphonic acid electrochemically deposited between two 55 μm spaced gold electrodes. At normal applied voltages, the low resistance devices act as passive circuit elements, not affecting the current flow. However during a current surge the devices switch from ohmic to non-ohmic behaviour, limiting current through the device. After the current surge has passed, the devices reset back to their original state. Our studies show that a partial de-doping/re-doping process caused by the rapid diffusion of moisture out of or into the polymer film during joule heating/cooling is the underlying mechanism responsible.
Control of domain wall pinning by localised focused Ga + ion irradiation on Au capped NiFe nanowires
Authors: Burn D. M. , Atkinson D.
Published: October 2014

Understanding domain wall pinning and propagation in nanowires are important for future spintronics and nanoparticle manipulation technologies. Here, the effects of microscopic local modification of the magnetic properties, induced by focused-ion-beam intermixing, in NiFe/Au bilayer nanowires on the pinning behavior of domain walls was investigated. The effects of irradiation dose and the length of the irradiated features were investigated experimentally. The results are considered in the context of detailed quasi-static micromagnetic simulations, where the ion-induced modification was represented as a local reduction of the saturation magnetization. Simulations show that domain wall pinning behavior depends on the magnitude of the magnetization change, the length of the modified region, and the domain wall structure. Comparative analysis indicates that reduced saturation magnetisation is not solely responsible for the experimentally observed pinning behavior.
Room temperature broadband terahertz gains in graphene heterostructures based on inter-layer radiative transitions
Authors: Tang Linlong , Du Jinglei , Shi Haofei , Wei Dongshan , Du Chunlei
Published: October 2014

We exploit inter-layer radiative transitions to provide gains to amplify terahertz waves in graphene heterostructures. This is achieved by properly doping graphene sheets and aligning their energy bands so that the processes of stimulated emissions can overwhelm absorptions. We derive an expression for the gain estimation and show the gain is insensitive to temperature variation. Moreover, the gain is broadband and can be strong enough to compensate the free carrier loss, indicating graphene based room temperature terahertz lasers are feasible.
Polarization induced resistance switching effect in ferroelectric vinylidene-fluoride/trifluoroethylene copolymer ultrathin films
Authors: Usui S. , Nakajima T. , Hashizume Y. , Okamura S.
Published: October 2014

We observed a clear polarization reversal-induced resistance switching effect in ferroelectric Vinylidene-fluoride (VDF)/Trifluoroethylene (TrFE) copolymer thin films. Pt and Au were used as the bottom and top electrodes, respectively, and the thickness of the VDF/TrFE copolymer film was adjusted to be 10 nm. The conduction current was 100 times higher in the case of the spontaneous polarization of the VDF/TrFE film towards the Au electrode than that in the case of the opposite direction. This resistance switching was confirmed to be reproducible after 10 successive polarization reversals.
Investigation of deformations and strain fields in silicon matrix structures embedded with vertically stacked Ge(Si) self-assembled islands
Authors: Pavlov D. A. , Bobrov A. I. , Novikov A. V. , Sorokin D. S. , Malekhonova N. V. , Pirogov A. V. , Nikolitchev D. E. , Boryakov A. V.
Published: October 2014

Elastic strains have been measured quantitatively and clearly demonstrated, resulting in vertical stacking of Ge(Si) self-assembled islands in a silicon matrix using the geometric phase analysis method. The strains are calculated on the basis of the data on the elemental composition and crystal-lattice distortions. An empirical approach on the basis of the experiment has allowed the determination of geometric phase method in accuracy.
Uridine adenosine tetraphosphate is a novel neurogenic P2Y1 receptor activator in the gut
Authors: Durnin Leonie , Hwang Sung Jin , Kurahashi Masaaki , Drumm Bernard T. , Ward Sean M. , Sasse Kent C. , Sanders Kenton M. , Mutafova-Yambolieva Violeta N.
Published: October 2014

Significance

Millions of people suffer of gastrointestinal (GI) motility disorders. P2Y1 purine receptors and Ca
2+
-activated small-conductance K
+
(SK) channels are established as key mediators of enteric inhibitory neurotransmission in the distal GI tract. However, the identity of the purinergic neurotransmitter in the bowel is controversial. We describe uridine adenosine tetraphosphate (Up4A) as a highly potent native activator of purinergic P2Y1 receptors and SK channels that is released spontaneously and during nerve stimulation in the human and mouse colons. We characterized potential sites of release, mimicry of the endogenous neurotransmitter, action on postjunctional targets, and metabolic pathways for Up4A. Our data identify Up4A as a novel factor in the purinergic signaling in the gut, including enteric inhibitory motor neurotransmission.
Empires ancient and modern: strength, modernity and power in imperial ideology from the Liberal period to Fascism
Authors: Cerasi Laura
Published: October 2014

This article examines the image of Empire developed in public discourse in Italy during the late Liberal period and Fascism by placing it in the context of representations of the British Empire, with which Italian imperial ambitions were compared. There is a continuity in seeing the British Empire as the expression of industrial and commercial modernity and its resultant strength, but what in the Liberal period was seen as an unparalleled superiority became under Fascism a supremacy acquired in a particular period but now exhibiting signs of decline, which Fascism should contest and surpass. Admiration of the British was mixed with disparagement: key figures expressed a competitive resentment towards Britain and its dominant international position, seeing it as the epitome of ‘modern’ imperial power against which Fascism was destined to be measured. In the 1930s signs of the British Empire's decline were sought, developing the idea in Gibbon's Decline and Fall of the Roman Empire that British domination would also rise and fall, and announcing the replacement of the ‘British order’, founded on commercial modernity and the strength of money and capital, by Fascism's new civilisation, with its authentic heritage of imperial romanità. This competitiveness towards Britain, which historiography has principally seen as a component of foreign policy (as was clear over Ethiopia), has additional significance when seen as an element of political culture that relates to the concept of the State. The autonomy and strength of the State were an important feature of Fascism's self-representation and of its legal culture, and in this light the possession of an empire came to be seen as an essential aspect of statehood and power.
Deep Infection after Total Hip Replacement: A Method for National Incidence Surveillance
Authors: Lindgren Viktor , Gordon Max , Wretenberg Per , Kärrholm Johan , Garellick Göran
Published: October 2014

Objective.

The purpose of this study was to estimate the incidence of deep periprosthetic joint infections (PJIs) after primary total hip replacement (THR) in Sweden prior to the introduction of a national initiative to reduce these infections.

Design.

Prospective open cohort study with 2 years follow-up of each subject.

Setting.

All THR-performing clinics in Sweden.

Methods.

All patients registered for a primary THR in the Swedish Hip Arthroplasty Register between July 1, 2005, and December 31, 2008, were selected for the study (45,531 patients with 49,219 THRs) and were matched with the Swedish Prescribed Drug Register. All patients with a minimum of 4 weeks of continuous outpatient antibiotic treatment within 2 years after their primary THR (1,989 patients with 2,219 THRs) were selected for a medical records review, and the number of cases with PJI was determined.

Results.

The cumulative incidence of PJI within 2 years after primary THR was 0.9% (95% confidence interval, 0.85–1.02; n = 443), and 405 of these had been reoperated. The incidence rate of PJI for the first 3 months was 5 per 10,000 THR-weeks and, thereafter, 0.3 per 10,000 THR-weeks. Staphylococcus aureus and coagulase-negative staphylococci were the most common bacteria isolated.

Conclusions.

This study describes a new method of national postoperative infection surveillance. The incidence is similar to previous smaller reports and is useful for monitoring changes over time to evaluate the national initiative to reduce infections.
On growth and form ofBacillus subtilisbiofilms
Authors: Dervaux Julien , Magniez Juan Carmelo , Libchaber Albert
Published: October 2014

A general feature of mature biofilms is their highly heterogeneous architecture that partitions the microbial city into sectors with specific micro-environments. To understand how this heterogeneity arises, we have investigated the formation of a microbial community of the model organismBacillus subtilis. We first show that the growth of macroscopic colonies is inhibited by the accumulation of ammoniacal by-products. By constraining biofilms to grow approximately as two-dimensional layers, we then find that the bacteria which differentiate to produce extracellular polymeric substances form tightly packed bacterial chains. In addition to the process of cellular chaining, the biomass stickiness also strongly hinders the reorganization of cells within the biofilm. Based on these observations, we then write a biomechanical model for the growth of the biofilm where the cell density is constant and the physical mechanism responsible for the spreading of the biomass is the pressure generated by the division of the bacteria. Besides reproducing the velocity field of the biomass across the biofilm, the model predicts that, although bacteria divide everywhere in the biofilm, fluctuations in the growth rates of the bacteria lead to a coarsening of the growing bacterial layer. This process of kinetic roughening ultimately leads to the formation of a rough biofilm surface exhibiting self-similar properties. Experimental measurements of the biofilm texture confirm these predictions.
Ratchets in hydrodynamic flow: more than waterwheels
Authors: Sturm James C. , Cox Edward C. , Comella Brandon , Austin Robert H.
Published: October 2014

The transport of objects in microfluidic arrays of obstacles is a surprisingly rich area of physics and statistical mechanics. Tom Duke's mastery of these areas had a major impact in the development of biotechnology which uses these ideas at an increasing scale. We first review how biological objects are transported in fluids at low Reynolds numbers, including a discussion of electrophoresis, then concentrate on the separation of objects in asymmetric arrays, sometimes called Brownian ratchets when diffusional symmetry is broken by the structures. We move beyond this to what are called deterministic arrays where non-hydrodynamic forces in asymmetric arrays allow for extraordinary separation, and we look to the future of using these unusual arrays at the nanoscale and at the hundreds of micrometre scale. The emphasis is on how the original ideas of Tom Duke drove this work forward.
Caldicellulosiruptor changbaiensis sp. nov., a cellulolytic and hydrogen-producing bacterium from a hot spring
Authors: Bing Wei , Wang Honglei , Zheng Baisong , Zhang Feng , Zhu Guangshan , Feng Yan , Zhang Zuoming
Published: October 2014

A novel thermophilic bacterial strain, CBS-ZT, was isolated from a terrestrial hot spring in the Changbai Mountains, PR China. Cells of strain CBS-ZT were short straight rods without flagella and had Gram-positive cell walls. Growth was observed at 40–90 °C (optimum 75 °C) and at pH 5.6–8.6 (optimum pH 7.8). The primary end-products from the fermentation of filter paper by strain CBS-ZT were acetate, lactate, H2, and CO2. The main cellular fatty acids were iso-C17 : 0, iso-C14 : 0 3-OH and C16 : 0. The G+C content of the genomic DNA was 36.08 mol%. Multiple sequence alignment of the 16S rRNA gene sequence and phylogenetic analyses indicated that strain CBS-ZT belongs to the genus

Caldicellulosiruptor

and the most similar micro-organism was

Caldicellulosiruptor saccharolyticus

DSM 8903T (96.36 % 16S rRNA gene sequence similarity); the 16S rRNA gene sequence similarity of strain CBS-ZT to other species was below 95 %. Based on its phylogenetic and phenotypic characteristics, strain CBS-ZT represents a novel species of the genus

Caldicellulosiruptor

, for which the name Caldicellulosiruptor
changbaiensis sp. nov. is proposed. The type strain is CBS-ZT ( = DSM 26941T = CGMCC 1.5180T).
Listeria booriae sp. nov. and Listeria newyorkensis sp. nov., from food processing environments in the USA
Authors: Weller Daniel , Andrus Alexis , Wiedmann Martin , den Bakker Henk C.
Published: October 2014

Sampling of seafood and dairy processing facilities in the north-eastern USA produced 18 isolates of

Listeria

spp. that could not be identified at the species-level using traditional phenotypic and genotypic identification methods. Results of phenotypic and genotypic analyses suggested that the isolates represent two novel species with an average nucleotide blast identity of less than 92 % with previously described species of the genus

Listeria

. Phylogenetic analyses based on whole genome sequences, 16S rRNA gene and sigB gene sequences confirmed that the isolates represented by type strain FSL M6-0635T and FSL A5-0209 cluster phylogenetically with

Listeria cornellensis

. Phylogenetic analyses also showed that the isolates represented by type strain FSL A5-0281T cluster phylogenetically with

Listeria riparia

. The name Listeria booriae sp. nov. is proposed for the species represented by type strain FSL A5-0281T ( = DSM 28860T = LMG 28311T), and the name Listeria newyorkensis sp. nov. is proposed for the species represented by type strain FSL M6-0635T ( = DSM 28861T = LMG 28310T). Phenotypic and genotypic analyses suggest that neither species is pathogenic.
A systematic survey of an intragenic epistatic landscape
Authors: Bank Claudia , Hietpas Ryan T. , Jensen Jeffrey D. , Bolon Daniel N.A.
Published: October 2014

Mutations are the source of evolutionary variation. The interactions of multiple mutations can have important effects on fitness and evolutionary trajectories. We have recently described the distribution of fitness effects of all single mutations for a nine amino acid region of yeast Hsp90 (Hsp82) implicated in substrate binding. Here, we report and discuss the distribution of intragenic epistatic effects within this region in seven Hsp90 point mutant backgrounds of neutral to slightly deleterious effect, resulting in an analysis of more than 1000 double-mutants. We find negative epistasis between substitutions to be common, and positive epistasis to be rare – resulting in a pattern that indicates a drastic change in the distribution of fitness effects one step away from the wild type. This can be well explained by a concave relationship between phenotype and genotype (i.e., a concave shape of the local fitness landscape), suggesting mutational robustness intrinsic to the local sequence space. Structural analyses indicate that, in this region, epistatic effects are most pronounced when a solvent-inaccessible position is involved in the interaction. In contrast, all 18 observations of positive epistasis involved at least one mutation at a solvent-exposed position. By combining the analysis of evolutionary and biophysical properties of an epistatic landscape, these results contribute to a more detailed understanding of the complexity of protein evolution.
Intron evolution in Neurospora: the role of mutational bias and selection
Authors: Sun Yu , Whittle Carrie A. , Corcoran Pádraic , Johannesson Hanna
Published: October 2014

We used comparative and population genomics to study intron evolutionary dynamics in the fungal model genus Neurospora. For our investigation, we used well-annotated genomes of N. crassa, N. discreta, and N. tetrasperma, and 92 resequenced genomes of N. tetrasperma from natural populations. By analyzing the four well-annotated genomes, we identified 9495 intron sites in 7619 orthologous genes. Our data supports nonhomologous end joining (NHEJ) and tandem duplication as mechanisms for intron gains in the genus and the RT-mRNA process as a mechanism for intron loss. We found a moderate intron gain rate (5.78–6.89 × 10−13 intron gains per nucleotide site per year) and a high intron loss rate (7.53–13.76 × 10−10 intron losses per intron sites per year) as compared to other eukaryotes. The derived intron gains and losses are skewed to high frequencies, relative to neutral SNPs, in natural populations of N. tetrasperma, suggesting that selection is involved in maintaining a high intron turnover. Furthermore, our analyses of the association between intron population-level frequency and genomic features suggest that selection is involved in shaping a 5′ intron position bias and a low intron GC content. However, intron sequence analyses suggest that the gained introns were not exposed to recent selective sweeps. Taken together, this work contributes to our understanding of the importance of mutational bias and selection in shaping the intron distribution in eukaryotic genomes.
Crystal structure of ammonium 3′-azido-3′-deoxythymidine-5′-aminocarbonylphosphonate hemihydrate: an anti-HIV agent
Authors: Jasko Maxim V. , Gurskaya Galina V. , Kukhanova Marina K. , Bushmarinov Ivan S.
Published: October 2014

The asymmetric unit of the title compound, NH4+·C11H14N6O7P−·0.5H2O, contains one 3′-azido-3′-deoxythymidine-5′aminocarbonylphosphonate (ACP–AZT) anion, half of an NH4+cation lying on a twofold rotation axis and in another position, occupied with equal probabilities of 0.5, an NH4+cation and a water molecule. The amide group of the ACP–AZT anion is disordered (occupancy ratio 0.5:0.5), with one part forming an N—H...O (involving C=O...H4N+) hydrogen bond and the other an O—H...N (involving C—NH2...OH2) hydrogen bond with the components of the split NH4+/H2O position. The pseudorotation parameters of ACP–AZT set it apart from previously studied AZT and thymidine. In the crystal, the various components are linked by N—H...O, O—H...O, N—H...N, C—H...O and C—H...N hydrogen bonds, forming a three-dimensional framework.
Crystal structure of dichlorido[2-(1H-imidazol-2-yl-κN3)imidazolato-κN]bis(tri-n-butylphosphane-κP)rhodium(III)
Authors: Jin-Long  , Ebihara Masahiro
Published: October 2014

In the title compound, [Rh(C6H5N4)Cl2(C12H27P)2], the RhIIIion is chelated by the singly deprotonated 2,2′-biimidazolate (Hbim−) ligand and coordinated by two chloride ions and two tri-n-butylphosphane ligands. The chloride ions and N atoms of the Hbim−ligand lie in a plane where the sum ofX—Rh—Xangles betweencissites is 360°. The phosphane ligands occupy the sites perpendicular to the plane, completing the overall distorted octahedral coordination sphere. The complex forms a self-complementary hydrogen-bonded dimer with the inversion-related complex through N—H...N hydrogen bonds.
Crystal structure ofN′-[(1E)-1-(6-methyl-2,4-dioxo-3,4-dihydro-2H-pyran-3-ylidene)ethyl]benzenesulfonohydrazide
Authors: Asegbeloyin Jonnie N. , Ujam Oguejiofo T. , Ngige Chizoba M. , Onwukeme Valentine I. , Groutso Tania
Published: October 2014

In the title compound, C14H14N2O5S, the molecule exists in the enamine (C=C—NH) tautomeric form. The hydrazone fragment derived from the 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one moiety is approximately planar, with a maximum deviation of 0.1291 (11) Å for the N atom bound to the S atom of the benzensulfonohydrazide group. The latter adopts agaucheconformation relative to the hydrazone N—N bond, with an N—N—S angle of 113.54 (10)°. There is an intramolecular N—H...O=C hydrogen bond that stabilizes the tautomeric form. In the crystal, molecules are linked by N—H...O=C hydrogen bonds into chains extending parallel to [100].
Crystal structure of poly[[μ3-4,4′-(4,4′-bipyridine-2,6-diyl)dibenzoato]{μ2-4-[6-(4-carboxyphenyl)-4,4′-bipyridin-4′-ium-2-yl]benzoato}manganese(II)] hemihydrate]
Authors: Li Yaping , Sun Dajun , Ming Julia , Han Liying , Su Guanfang
Published: October 2014

The title compound, {[Mn(C24H14N2O4)(C24H16N2O4)]·0.5H2O}n, was obtained by the reaction of manganese nitrate with the ligand 4,4′-(4,4′-bipyridine-2,6-diyl) dibenzoic acid under hydrothermal conditions. The water O atom is located on a twofold rotation axis. The Mn2+ion is heptacoordinated by six O atoms and one N atom from the ligands. In this structure, the ligands adopts two different forms, one completely deprotonated and one with a protonated N atom (pyridinium) and a carboxylic acid function. In the crystal, N—H...O and O—H...O hydrogen bonds consolidate the packing, forming a three-dimensional framework.
Crystal structure ofcatena-poly[[silver(I)-μ-N-(pyridin-2-ylmethyl)pyridine-3-amine-κ2N:N′] trifluoromethanesulfonate]
Authors: Moon Suk-Hee , Cho Seonghwa , Park Ki-Min
Published: October 2014

In the asymmetric unit of the title compound, {[Ag(C11H11N3)]CF3SO3}n, there are two AgIatoms, twoN-(pyridine-2-ylmethyl)pyridine-3-amine ligands (AandB) and two CF3SO3−anions. Both AgIatoms are bridged by two pyridine N atoms from two symmetry-relatedAorBligands, forming right- or left-handed helical chains, respectively. The AgIatom of the right-handed helical chain adopts a slightly distorted linear coordination geometry [N—Ag—N = 170.69 (14)°], while that of the left-handed helical chain adopts a bent geometry [N—Ag—N = 149.42 (14)°]. Both helical chains have the same pitch length [10.8437 (5) Å], propagate along theb-axial direction and are alternately arrangedviaAg...Ag [3.0814 (5) Å] and π–π stacking interactions [centroid–centroid distances = 3.514 (3) and 3.487 (3) Å], resulting in the formation of a two-dimensional supramolecular network extending parallel to theabplane. Weak Ag...O [2.861 (4), 2.617 (3), and 2.624 (4) Å] and Ag...F [3.017 (3) Å] interactions as well as N—H...O and C—H...O, C—H...N and C—H...F hydrogen-bonding interactions occur between the helical chains and the anions.
Crystal structure of (2E)-N-methyl-2-(2-oxo-1,2-dihydroacenaphthylen-1-ylidene)hydrazinecarbothioamide
Authors: Vimala G. , Govindaraj J. , Haribabu J. , Karvembu R. , SubbiahPandi A.
Published: October 2014

In the title compound, C14H11N3OS, the acenaphthylene ring system and hydrazinecarbothioamide unit (=N—NH—C=S—NH–) are essentially coplanar [with maximum deviations from their mean planes of −0.009 (2) and 0.033 (2) Å, respectively], and make a dihedral angle of 1.59 (9)°. The molecular conformation is stabilized by two weak intramolecular hydrogen bonds (N—H...O and N—H...N), which generateS(6) andS(5) ring motifs. In the crystal, molecules are linked by N—H...S hydrogen bonds, forming chains along [010]. The chains are linkedviapairs of C—H...O hydrogen bonds, enclosingR22(10) ring motifs, and C—H...π interactions, forming a three-dimensional framework. The absolute structure of the title compound was determined by resonant scattering.
In situproteolysis, crystallization and preliminary X-ray diffraction analysis of a VHH that binds listeria internalin B
Authors: Huh Ian , Gene Robert , Kumaran Jyothi , MacKenzie C. Roger , Brooks Cory L.
Published: October 2014

The variable region of camelid heavy-chain antibodies produces the smallest known antibody fragment with antigen-binding capability (a VHH). The VHH R303 binds internalin B (InlB), a virulence factor expressed by the pathogenListeria monocytogenes. InlB is critical for initiation ofListeriainfection, as it binds a receptor (c-Met) on epithelial cells, triggering the entry of bacteria into host cells. InlB is surface-exposed and is required for virulence, hence a VHH targeting InlB has potential applications for pathogen detection or therapeutic intervention. Here, the expression, purification, crystallization and X-ray diffraction of R303 are reported. Crystals of R303 were obtained followingin situproteolysis with trypsin. Gel filtration and SDS–PAGE revealed that trypsin removed the C-terminal tag region of R303, facilitating crystal formation. Crystals of R303 diffracted to 1.3 Å resolution and belonged to the monoclinic space groupP21, with unit-cell parametersa= 46.4,b= 31.2,c= 74.8 Å, β = 93.8°. The crystals exhibited a Matthews coefficient of 1.95 Å3 Da−1with two molecules in the asymmetric unit.
Crystallization and preliminary X-ray crystallographic analysis of an artificial molten-globular-like triosephosphate isomerase protein of mixed phylogenetic origin
Authors: Goyal Venuka Durani , Yadav Pooja , Kumar Ashwani , Ghosh Biplab , Makde Ravindra D.
Published: October 2014

A bioinformatics-based protein-engineering approach called consensus design led to the construction of a chimeric triosephosphate isomerase (TIM) protein called ccTIM (curated consensus TIM) which is as active asSaccharomyces cerevisiaeTIM despite sharing only 58% sequence identity with it. The amino-acid sequence of this novel protein is as identical to native sequences from eukaryotes as to those from prokaryotes and shares some biophysical traits with a molten globular protein. Solving its crystal structure would help in understanding the physical implications of its bioinformatics-based sequence. In this report, the ccTIM protein was successfully crystallized using the microbatch-under-oil method and a full X-ray diffraction data set was collected to 2.2 Å resolution using a synchrotron-radiation source. The crystals belonged to space groupC2221, with unit-cell parametersa= 107.97,b= 187.21,c= 288.22 Å. Matthews coefficient calculations indicated the presence of six dimers in the asymmetric unit, with an approximate solvent content of 46.2%.
Structure of the methanofuran/methanopterin-biosynthetic enzyme MJ1099 fromMethanocaldococcus jannaschii
Authors: Bobik Thomas A. , Morales Erick J. , Shin Annie , Cascio Duilio , Sawaya Michael R. , Arbing Mark , Yeates Todd O. , Rasche Madeline E.
Published: October 2014

Prior studies have indicated that MJ1099 fromMethanocaldococcus jannaschiihas roles in the biosynthesis of tetrahydromethanopterin and methanofuran, two key cofactors of one-carbon (C1) metabolism in diverse organisms including the methanogenic archaea. Here, the structure of MJ1099 has been solved to 1.7 Å resolution using anomalous scattering methods. The results indicate that MJ1099 is a member of the TIM-barrel superfamily and that it is a homohexamer. Bioinformatic analyses identified a potential active site that is highly conserved among MJ1099 homologs and the key amino acids involved were identified. The results presented here should guide further studies of MJ1099 including mechanistic studies and possibly the development of inhibitors that target the methanogenic archaea in the digestive tracts of humans and that are a source of the greenhouse gas methane.
Adapting smart specialisation to a micro-economy – the case of Malta
Authors: Georghiou Luke , Elvira Uyarra and , Saliba Scerri Ramona , Castillo Nadine , Cassingena Harper Jennifer
Published: October 2014

Purpose

– The purpose of this paper is to set out the process by which a smart specialisation strategy was developed for a small, peripheral economy in the European Union, the Republic of Malta. It assesses the applicability of the approach in the context of a micro-economy with an industrial structure based on a small number of foreign direct investments and a predominance of micro-enterprises.

Design/methodology/approach

– The paper follows an action research approach by presenting as a case study the process by which the strategy for Malta was assessed and developed through successive rounds of engagement with business and other actors with the application of scenarios and other prioritisation approaches to facilitate its development. An initial consultation with 20 public sector and representative organisations was followed by a general business workshop and 21 sectoral focus groups.

Findings

– Lack of critical mass can be mitigated by maximising the generic use of available skills and competences. Given the higher vulnerability to external shock in micro-economies, strategies need to have a high degree of flexibility and adaptability. Greater internationalisation provides the main response to peripherality.

Practical implications

– The approach can be applied more generally for micro-economies and in some aspects to other countries or regions lacking critical mass in research and innovation assets or facing peripherality.

Originality/value

– The smart specialisation approach had not been applied in these circumstances and hence the findings allowed the concept to be extended and adapted to deal with the issues raised.
Smart specialisation in European regions: issues of strategy, institutions and implementation
Authors: McCann Philip , Ortega-Argilés Raquel
Published: October 2014

Purpose

– The purpose of this paper is to show that the approaches to smart specialisation being adopted in different European Union (EU) regions are likely to be heavily shaped by the institutional and governance context, as well as the regional economic specifics. Along with the specific regional economic characteristics, these institutional variations mean that there is no single smart specialisation template or blueprint which can be transplanted onto every region. Rather, regions have to work within their own governance frameworks to find their best solutions.

Design/methodology/approach

– As evidence of this, the authors analyse the possibilities and challenges faced by four different sets of regional examples in the UK, the Netherlands, Belgium and Spain. Using OECD, EU and other official national documents and publications, the authors are able to explain the ways in which the governance set-ups vary enormously across these different arenas although they do share some certain common features with the other examples on a case-by-case basis.

Findings

– The policy architecture within which the smart specialisation agenda will be operating is very different in each national or regional case. As such, in addition to the regional economic specifics, the smart specialisation challenges faced by different regions are likely to differ significantly due to governance issues as well as variations in the regional economic conditions. This is because the possibilities for different regional actions depend heavily on the governance relationship between the regional and the local governance remits.

Research limitations/implications

– The argument presented here are necessarily in part speculative in that while they are based on a regional systems-of-innovation conceptual framework which links institutions, innovation and regional development, the actual smart specialisation implementation processes are still in their infancy, so that the actual outcomes remain to be seen in the long run.

Practical implications

– The analysis here helps to situate smart specialisation discussions in the national-regional institutional and governance context. This also serves to frame how smart specialisation priority-setting processes are likely to be undertaken and helps to consider how such activities may play out in other regions with different institutional settings.

Originality/value

– This is one of the few papers that explicitly examine specialisation issues in a governance and institutional setting. In reality, the success or otherwise of smart specialisation agenda will be heavily shaped by how the governance and institutional issues are addressed. Good analysis and data gathering is essential, but good governance for policy design, monitoring and evaluation can potentially also provide a crucial advantage to smart specialisation actions. In contrast, poor governance may undermine good smart specialisation intentions and analyses.
Guest editorial on research and innovation strategies for smart specialisation in Europe
Authors: Landabaso Mikel
Published: October 2014

Purpose

– This Special Issue of the European Journal of Innovation Management sheds new light on the burning issue of Research and Innovation Strategies for Smart Specialisation (RIS3), both in terms of their policy formulation and their practical implementation in the field. This new policy approach refers to the process of priority setting in national and regional research and innovation strategies in order to build “place-based” competitive advantages and help regions and countries develop an innovation-driven economic transformation agenda. The paper aims to discuss these issues.

Design/methodology/approach

– This is an important topic both in the current debate about a new industrial policy for Europe and as a policy option for a successful crisis exit strategy led by public investments in the real economy. Moreover, smart specialisation is promoted by the European Commission as an ex ante conditionality for all regions in Europe to receive European Structural and Investment Funds in the field of innovation. Thus, it has become a pre-requisite for accessing fresh funds for investing in badly needed innovation-driven productivity growth throughout the European Union (EU).

Findings

– The six papers in this Special Issue are the fruit of ground-breaking research and policy testing by nearly 20 leading academics and policy makers throughout the EU. They explore the early smart specialisation concept and its further developments, examine the methodological tools at its disposal and advance specific policy proposals and governance considerations based on actual experimentation in the field.

Originality/value

– All these make the present Special Issue of the European Journal of Innovation Management an important research milestone. This Special Issue is the fruit of a call towards the European academic and research community to help shaping and advancing the smart specialisation concept and thus contribute to better position regions and countries in the global economy through innovation-driven policies.
Workforce ageing and the training propensity of Italian firms
Authors: Guerrazzi Marco
Published: October 2014

Purpose

– The purpose of this paper is to take into consideration the propensity to offer vocational training of a large sample of Italian private firms by retrieving cross-sectional data from INDACO (2009).

Design/methodology/approach

– Estimating a probit model, the author assesses how the age and the gender composition of the employed workforce, as well as a set of relevant corporate characteristics, such as size, sector, geographical location, innovation strategies, R&D investments and use of social safety valves, are linked to the willingness of firms to supply on-the-job training.

Findings

– First, as far as the average age of the whole employed workforce is concerned, it was found that the propensity of surveyed firms toward training provision follows an inverted U-shaped pattern. Furthermore, it was shown that larger firms have a higher training propensity with respect to small firms, and the same attitude holds for productive units that adopted innovation strategies and/or invested in R&D projects. By contrast, it was found that the propensity to support training activities is negatively correlated to the percentage of employed women and the use social valves.

Research limitations/implications

– The sample of business units taken into consideration is quite large, but it has some biases toward larger and manufacturing firms. Moreover, the cross-sectional perspective of the analysis does not allow implementation of the finer identification procedures that can be applied with panel data. Furthermore, the lack of employer – employee linked data does not allow to fully address the issue of compliance to training activities.

Social implications

– From a policy point of view, the results shown throughout the paper suggest some broad guidelines. First, especially in small firms, vocational training for young and older workers should be somehow stimulated. Moreover, as far as mature employees are concerned, those interventions should be framed in an active ageing perspective. Subsidies and targeted job placement programmes are often claimed as being the most appropriate ways to improve the underprivileged position of older workers. However, continuous learning during the whole working life still appears as the most effective device to reduce the employment disadvantages in the older years.

Originality/value

– While there are a number of papers that study the age patterns of training participation by using workers’ data retrieved from personnel and/or labour force surveys, this work is the first attempt to provide a probabilistic assessment of the decisions of Italian firms regarding training provision by taking into account the ageing perspectives of the incumbent workforce.
Unpacking the relationship between organizational culture and excellent leadership in public relations
Authors: Meng Juan
Published: October 2014

Purpose

– By looking into the relationship between organizational culture and excellent leadership in public relations, the purpose of this paper is bifold: first, how and to what extent organizational culture can affect leadership effectiveness in communication management; and second, what possible impact excellent leadership in public relations may generate to reshape organizational culture in a way to further support the value of public relations.

Design/methodology/approach

– An online survey was distributed to a randomly selected group of 1,000 senior public relations executives in the USA by using the PR executive database of Heyman Associates, a PR executive search firm in New York City. A final sample of 222 senior public relations executives was recruited. This group of respondents mirrored the characteristics of senior executives in the public relations profession in the USA.

Findings

– The results identified the reciprocal relationship between organizational culture and excellent leadership in public relations. The testing of a non-recursive structural model confirmed that organizational culture generates a direct, positive effect on the achievement of excellent leadership in public relations. More importantly, excellent leadership in public relations also influences organizational culture by reshaping it in a favorable way to support public relations efforts in the organization.

Originality/value

– There is insufficient empirical research linking public relations leadership and organizational culture, although it is agreed these two institutional conditions are critical. Thus, this study unpacked the independent and dependent roles of organizational culture in influencing leadership effectiveness in public relations, which may generate implications for both research and practice purposes.
An attributional analysis of corporate reporting in crisis situations
Authors: Tennert Falk
Published: October 2014

Purpose

– The purpose of this paper is to use an attributional approach to examine press coverage in Germany dealing with Toyota’s 2010 global product recall due to purportedly defective brakes. The research focuses on the attributions of cause and responsibility and, thereby, the practices of media-brokered selection and interpretation of events.

Design/methodology/approach

– The methodology used is a quantitative content analysis of selected German print media. Corporate reporting is analysed with the help of attribution theory approaches from the field of psychology, which, when applied to public relations themes, thereby enables the identification of latent and manifest risk factors that emerge from the perceived responsibility of the media.

Findings

– Causal attributions are an essential aspect of coverage in acute crisis situations. The key findings show a dominance of internal attributions of responsibility in which the media interprets the crisis as self inflicted and ascribes a high level of fault on the company. Exonerating attributions according to a self-serving bias find little resonance in the coverage. The responsibility attributed to Toyota by the media coverage to a sustained damage to the company’s reputation.

Originality/value

– The study demonstrates that attribution theory can be productively applied to questions of communication management. This approach enables an analysis of attribution discourse as well as the potential long-term effects on the company’s reputation. Thus, the original value of this study lies in the psychological foundation of organisational risk and opportunity.
Policy and institutions facilitating entrepreneurial spin-offs: USA, Asia and Europe
Authors: Caiazza Rosa , Audretsch David , Volpe Tiziana , Debra Singer Julie
Published: October 2014

Purpose

– Existing work documents the role that institutional setting plays in the process of spin-off creation. However, despite decades of studies, scholars have not clearly explained why some regions are more involved in spin-off activity than others. Drawing from institutional theory, the purpose of this paper is to compare different institutional settings identifying factors affecting the general environment capability to support spin-off activity of a specific region.

Design/methodology/approach

– The authors utilize a cross-national analysis of American, Asian, and European areas identifying factors affecting their different rate of spin-off activity. This study contributes to the policy debate concerning entrepreneurship and how best to spur spin-off activities.

Findings

– In this paper, the authors identify the general and specific factors that explain the cross-national diversity in spin-off creation. The authors then perform an analysis of the impact of these factors in various regions of the USA, Asia, and Europe, providing evidence for the necessity of specific combinations of these factors.

Originality/value

– The paper offers a new perspective on the causes of spin-offs through a cross-national analysis of many areas around the world.