bluuebunny/crossref_metadata_2025 huggingface dataset:
First-principles study of the magnetic stability and the exchange couplings of LaMn2O5
Authors: El Hallani F. , Naji S. , Ez-Zahraouy H. , Benyoussef A.
Published: October 2013

Using first principles calculations, the electronic and magnetic properties of the multiferroic LaMn2O5 have been studied. In particular, we have studied the magnetic stability of this material not only in ab-plane but also along c direction. Beside this, the exchange couplings between manganese ions have been calculated using Heisenberg model by including only the nearest neighbour interactions. It is shown that the stable magnetic order of LaMn2O5 is of antiferromagnetic type, which is in good agreement with the experiments. In order to show the effect of the temperature on the properties of our compound we have carried out this study using two crystal structures: the higher symmetric one (space group Pbam) that reported experimentally at T(98.8 k) and the lower symmetric one (space group Pmc21) that obtained from the relaxation, in our calculations, at T = 0 K starting from the stable magnetic order.This structure deformation at T = 0 can be related to the exchange coupling striction. The density of states show an insulating behavior in the antiferromagnetic state of LaMn2O5 at Fermi level and there is a small band gap, confirming the experimental fact that LaMn2O5 is an insulator. We have found that the nature of the mechanism of these magnetic exchange coupling is an indirect super-exchange.
Sensitivity of resistive and Hall measurements to local inhomogeneities
Authors: Koon Daniel W. , Wang Fei , Hjorth Petersen Dirch , Hansen Ole
Published: October 2013

We derive exact, analytic expressions for the sensitivity of resistive and Hall measurements to local inhomogeneities in a specimen's material properties in the combined linear limit of a weak perturbation over an infinitesimal area in a small magnetic field. We apply these expressions both to four-point probe measurements on an infinite plane and to symmetric, circular van der Pauw discs, obtaining functions consistent with published results. These new expressions speed up calculation of the sensitivity for a specimen of arbitrary shape to little more than the solution of two Laplace equation boundary-value problems of the order of N3 calculations, rather than N2 problems of total order N5, and in a few cases produces an analytic expression for the sensitivity. These functions provide an intuitive, visual explanation of how, for example, measurements can predict the wrong carrier type in n-type ZnO.
Preliminary physical and electromagnetic design for the injector of the heavy ion superconducting linac
Authors: Hong I. S. , Kim Y. , Kim H. J. , Choi B. H. , Jeon D. , Bahng J. B. , Kim E. S.
Published: October 2013

The Rare Isotope Science Project in Korea has developed a high current heavy ion accelerator using superconducting linacs. A normal conducting injector system was proposed to supply heavy ions to the superconducting driver linac. A beam physics and engineering design study was performed, and the beam dynamics of the injector was simulated. Optimized beam transmission and emittance were obtained from the beam dynamics simulation. Various normal conducting bunchers, such as multi-harmonic buncher, velocity equalizer, radiofrequency quadrupole, and re-bunchers, will be used and have been electromagnetically calculated.
Iminopropadienones RN=C=C=C=O and bisiminopropadienes RN=C=C=C=NR: Matrix infrared spectra and anharmonic frequency calculations
Authors: Bégué Didier , Baraille Isabelle , Andersen Heidi Gade , Wentrup Curt
Published: October 2013

Methyliminopropadienone MeN=C=C=C=O 1a was generated by flash vacuum thermolysis from four different precursors and isolated in solid argon. The matrix-isolation infrared spectrum is dominated by unusually strong anharmonic effects resulting in complex fine structure of the absorptions due to the NCCCO moiety in the 2200 cm−1 region. Doubling and tripling of the corresponding absorption bands are observed for phenyliminopropadienone PhN=C=C=C=O 1b and bis(phenylimino)propadiene PhN=C=C=C=NPh 9, respectively. Anharmonic vibrational frequency calculations allow the identification of a number of overtones and combination bands as the cause of the splittings for each molecule. This method constitutes an important tool for the characterization of reactive intermediates and unusual molecules by matrix-isolation infrared spectroscopy.
Microfluidic devices for cell cultivation and proliferation
Authors: Tehranirokh Masoomeh , Kouzani Abbas Z. , Francis Paul S. , Kanwar Jagat R.
Published: October 2013

Microfluidic technology provides precise, controlled-environment, cost-effective, compact, integrated, and high-throughput microsystems that are promising substitutes for conventional biological laboratory methods. In recent years, microfluidic cell culture devices have been used for applications such as tissue engineering, diagnostics, drug screening, immunology, cancer studies, stem cell proliferation and differentiation, and neurite guidance. Microfluidic technology allows dynamic cell culture in microperfusion systems to deliver continuous nutrient supplies for long term cell culture. It offers many opportunities to mimic the cell-cell and cell-extracellular matrix interactions of tissues by creating gradient concentrations of biochemical signals such as growth factors, chemokines, and hormones. Other applications of cell cultivation in microfluidic systems include high resolution cell patterning on a modified substrate with adhesive patterns and the reconstruction of complicated tissue architectures. In this review, recent advances in microfluidic platforms for cell culturing and proliferation, for both simple monolayer (2D) cell seeding processes and 3D configurations as accurate models of in vivo conditions, are examined.
Core level photoemission studies on conducting polypyrrole polymer nanotubes showing switching transitions
Authors: Sarkar I. , Sarma A. , Sanyal M. K. , Thieß S. , Drube W.
Published: October 2013

Conducting polypyrrole (PPY) nanotubes is a classical model system for strongly correlated disordered materials showing intriguing switching transitions from low to high conductivity states at low temperature. This switching behaviour can be tuned by incorporating gold nanoclusters to form composite nanotubes (AuPPY). Here, we present core level electronic structure studies on PPY and AuPPY nanotubes with different diameters using hard X-ray photoemission spectroscopy at room temperature. The spectroscopic data provide information on the role of diameter as well as metal cluster incorporation for a modification of the electronic structure of this important class of nanotubes. Furthermore, electrical transport measurements were performed at low temperature to extract the change in localization length and doping level in these nanotubes. Based on these results, we explain the observed electrical transport behavior of these nanotubes as the interplay of disorder and carrier concentration.
Growth mechanism and microstructure of low defect density InN (0001) In-face thin films on Si (111) substrates
Authors: Kehagias Th. , Dimitrakopulos G. P. , Ajagunna A. O. , Koukoula T. , Tsagaraki K. , Adikimenakis A. , Komninou Ph. , Georgakilas A.
Published: October 2013

Transmission electron microscopy has been employed to analyze the direct nucleation and growth, by plasma-assisted molecular beam epitaxy, of high quality InN (0001) In-face thin films on (111) Si substrates. Critical steps of the heteroepitaxial growth process are InN nucleation at low substrate temperature under excessively high N-flux conditions and subsequent growth of the main InN epilayer at the optimum conditions, namely, substrate temperature 400–450 °C and In/N flux ratio close to 1. InN nucleation occurs in the form of a very high density of three dimensional (3D) islands, which coalesce very fast into a low surface roughness InN film. The reduced reactivity of Si at low temperature and its fast coverage by InN limit the amount of unintentional Si nitridation by the excessively high nitrogen flux and good bonding/adhesion of the InN film directly on the Si substrate is achieved. The subsequent overgrowth of the main InN epilayer, in a layer-by-layer growth mode that enhances the lateral growth of InN, reduces significantly the crystal mosaicity and the density of threading dislocations is about an order of magnitude less compared to InN films grown using an AlN/GaN intermediate nucleation/buffer layer on Si. The InN films exhibit the In-face polarity and very smooth atomically stepped surfaces.
Unique pattern of close-packed colloid film observed by polarized light microscopy
Authors: Heon Kim Joon , Su Park Jung , Kim Seo-Hyang
Published: October 2013

Polarized light microscopy has been extensively used in the research of anisotropic material such as liquid crystal, but not often in the study of the close-packed colloid film. Here, we show that the polarized microscopy can be much more effective than the bright-field or the dark-field microscopy in identifying domain orientation and boundary as well as in distinguishing regions of the different number of layers in the close-packed microsphere colloid film due to its unique pattern and enhanced contrast. Origins for these unique properties could be well explained by the simple model based on the polarization rotation at the microsphere edges and the possible close-packed multilayer structures. These findings will renew the use of the polarized microscopy in the study of the close-packed colloid film.
The Competition State, City-Regions, and the Territorial Politics of Growth Facilitation
Authors: While Aidan , Gibbs David , Jonas Andrew E G
Published: October 2013

As urban centres of agglomeration expand and compete for investment, new demands may arise for additional housing, infrastructure, and services. Failure to meet these demands imposes costs on firms and workers, stifles expansion, and potentially compromises the long-run economic competitiveness of the growth area. Drawing on evidence from Germany (Munich), Sweden (Stockholm), and the UK (Cambridge) this paper examines the organisational and political challenges of growth facilitation in the context of post-Keynesian political and economic restructuring. Particular emphasis is placed on tensions arising from changes in the form and function of European state social regulation. These tensions are not simply a matter of neoliberal regulatory deficit but reflect broader societal cleavages in relation to the uneven spatial impact of local economic growth. Deploying the concept of territorial structures of growth facilitation provides a conceptual framework for taking forward research on the relationship between state spatial regulation, state restructuring, and the competitiveness of city-regions.
Fishing for Nature: The Politics of Subjectivity and Emotion in Scottish Inshore Fisheries Management
Authors: Nightingale Andrea
Published: October 2013

This paper explores the relational emergence of subjects, emotions, and socionatures and their consequences for Scottish inshore fishery management. Using a conception of the embodied spatial production of individual and collective subjectivities, and the ‘ambivalence’ of the subject, I explore why some fishers are committed to sustaining the fishing ground and others are not. Many people who work the land or the sea have a deep respect for and attachment to those environments, but overexploit them to make a living. How is it that people whose livelihoods depend on ‘natural’ environments embody apparently contradictory relationships with those environments? I probe such contradictions by exploring how the boundaries between subjects and environments are formed, and the consequences for Scottish inshore fisheries management of such boundary un/making. Using work from socionature, subjectivity, and emotional geographies, I show how fishing subjectivities are highly political and produce emotional and practical responses that have real consequences for how fisheries management plays out. Attending to the way in which subjectivities position fishers differently in relation to their resources and fisheries policies is therefore vital for successful management.
Local Energy Systems: Evaluating Network Effectiveness for Transformation in British Columbia, Canada
Authors: Berkhout Tom , Westerhoff> Lisa
Published: October 2013

Local governments across the Canadian province of British Columbia have begun to implement measures to achieve energy and greenhouse gas emission reduction targets. Among these, a handful of communities have emerged as leaders, supported by a network of organisations across sectors and scales. This study uses a social network analysis approach to explore the nature and extent of this network, coupled with qualitative interview data to determine its effectiveness. The study reveals that while the network is providing important resources and information, leading governments require specific forms of support to push innovative policies and actions further. In addition, though a shared vision of integrated local energy systems is emerging across the province, the lack of a systemic integration of goals across scales has created significant legislative barriers at the local scale.
Novel Multisector Networks and Entrepreneurship: The Role of Small Businesses in the Multilevel Governance of Climate Change
Authors: Burch Sarah , Schroeder Heike , Rayner Steve , Wilson Jennifer
Published: October 2013

While some jurisdictions are demonstrating leadership on climate change, it is clear that sufficient mitigation of climate change is not occurring. This highlights the importance of innovative approaches that bolster politically fraught international treaties and voluntary networks with strategies that exploit the strengths of a variety of traditional and nontraditional actors. With this paper we examine just such an innovation in the form of a multisector and multilevel network linking together the regional authority Metro Vancouver in the Canadian province of British Columbia, several municipal governments, a social enterprise, and a large number of small and medium-sized enterprises to act on climate change. This case demonstrates that while complementarity of actions across levels and sectors is not always achieved, it is nonetheless likely to contribute significantly to greenhouse gas emission reductions in the urban context. Interview and survey data also highlight that each sector and level of governance can provide what it is good at or capable of in order to enable others to contribute their share. Whether this is done on an ad hoc basis or in the form of partnerships, networks or agreements may vary from case to case, and further research is needed to understand what forms of multilevel and multisector partnerships, networks, and agreements are most conducive to achieving desired outcomes.
Intermediates in the Formation and Thermolysis of Peroxides from Oxidations with Singlet Oxygen
Authors: Fudickar Werner , Linker Torsten
Published: October 2013

Herein we describe the recent mechanistic understandings of the singlet oxygen ene reaction to give hydroperoxides and the [4+2] cycloaddition affording endoperoxides. Both experimental findings and theoretical work conclude in the formation of intermediates structurally similar to perepoxides during the ene reaction. Such intermediates mainly control the regio- and stereoselectivities of this reaction class. For the [4+2] cycloaddition, both a synchronous concerted reaction (benzene, naphthalenes) and a stepwise reaction with a non-symmetric zwitterionic intermediate (larger acenes) have been found. The thermolysis of endoperoxides derived from acenes proceeds stepwise for anthracenes, but in a concerted manner for less stable adducts such as naphthalene.
Nutritional composition of potential zooplankton prey of the spiny lobster phyllosoma (Jasus edwardsii)
Authors: Wang Miao , O'Rorke Richard , Nodder Scott D. , Jeffs Andrew G.
Published: October 2013

Despite the global significance of spiny lobsters, the biology of their planktonic larvae, especially their carnivorous diet, is very poorly understood. Unsuitable diets and feeding regimes are one of the major reasons for consistently high mortalities during larval culture. In an effort to begin to determine the nutritional requirements of phyllosoma larvae of the spiny lobster, Jasus edwardsii, the present study first characterised the proximate composition of 11 previously identified groups of their potential prey. This included gelatinous zooplankton (chaetognaths, ctenophores, tunicates, siphonophores, scyphozoans, heteropods and pteropods), crustacean zooplankton (amphipods, copepods and euphausiids) and fish larvae. The composition of the 54 samples of 30 species of zooplankton ranged over 79.2–98.1% moisture content, and 1.9–54.2% for protein, 0.4–11.2% for carbohydrate, 0.1–27.9% for lipid, and 3.9–76.4% for ash of dry weight. The results showed that, in the most, zooplankton species provide a reliable source of protein. Only a small number of zooplankton had high lipid yield, suggesting that a narrow range of zooplankton species high in lipid are likely to be targeted by late-stage phyllosomas. The results of the present study will be useful as a guide for the development of artificial diets to improve phyllosoma aquaculture.
Sulfur isotopes track the global extent and dynamics of euxinia during Cretaceous Oceanic Anoxic Event 2
Authors: Owens Jeremy D. , Gill Benjamin C. , Jenkyns Hugh C. , Bates Steven M. , Severmann Silke , Kuypers Marcel M. M. , Woodfine Richard G. , Lyons Timothy W.
Published: October 2013

Significance

Oxygen in the atmosphere and ocean rose dramatically about 600 Mya, coinciding with the first proliferation of animals. However, numerous biotic events followed when oxygen concentrations in the younger ocean dipped episodically. The Cretaceous is famous for such episodes, and the most extensive of these oceanic anoxic events occurred 93.9 Mya. Our combined carbon- and sulfur-isotope data indicate that oxygen-free and hydrogen sulfide-rich waters extended across roughly 5% of the global ocean, compared to <<1% today, but with the likelihood that much broader regions were also oxygen challenged. These conditions must have impacted nutrient availability in the ocean and ultimately the spatial and temporal distribution of marine life across a major climatic perturbation.
The
Arabidopsis
ZED1 pseudokinase is required for ZAR1-mediated immunity induced by the
Pseudomonas syringae
type III effector HopZ1a
Authors: Lewis Jennifer D. , Lee Amy Huei-Yi , Hassan Jana A. , Wan Janet , Hurley Brenden , Jhingree Jacquelyn R. , Wang Pauline W. , Lo Timothy , Youn Ji-Young , Guttman David S. , Desveaux Darrell
Published: October 2013

Significance

Bacterial pathogens can use a syringe-like structure to inject virulence proteins (effectors) directly into host cells. The YopJ/HopZ superfamily of effectors found in animal and plant pathogens can modify host kinase proteins to suppress host immunity. In the model plant
Arabidopsis
, HopZ1a is recognized by the resistance protein ZAR1 to induce a robust immune response that blocks pathogen growth. Here, we show that the HopZ1a effector from the plant pathogen
Pseudomonas syringae
targets the
Arabidopsis
nonfunctional pseudokinase ZED1 and that ZED1 is required for recognition of HopZ1a by ZAR1. We hypothesize that HopZ1a targets kinases to promote pathogen virulence, and
Arabidopsis
ZED1 evolved as a decoy to trap HopZ1a in the ZAR1 complex for recognition by the plant immune system.
Lexical bundles and L1 transfer effects
Authors: Paquot Magali
Published: October 2013

This exploratory study makes use of Jarvis’s (2000) methodological framework to investigate transfer effects on French EFL learners’ use of lexical bundles. The study focuses on 3-word recurrent sequences that include a lexical verb in the French component of the International Corpus of Learner English (ICLE) as compared to nine other ICLE learner sub-corpora. Results are in line with a usage-based view of language that recognizes the active role that the first language (L1) may play in the acquisition of a foreign language. The different manifestations of L1 influence displayed in the learners’ idiosyncratic use of lexical bundles are traced back to various properties of French words, including their collocational use, lexico-grammatical patterns, function, discourse conventions, and frequency of use. Following Hoey (2005), these transfer effects are subsumed under the general term of ‘transfer of primings’.
Frame blending in specialized language
Authors: Ureña Gómez-Moreno José Manuel , Faber Pamela , Castro Miriam Buendía
Published: October 2013

According to Frame-Based Terminology (Faber et al. 2005, 2006, 2007), a crucial issue in terminology management is how specialized concepts should be represented within the knowledge structure of a scientific domain. This paper proposes a model of specialized concept representation based on conceptual frames (Faber et al. 2006, 2007; Faber 2011) and blends (Fauconnier 1999; Fauconnier and Turner 1998, 2002). Although frame-blending has been documented in general language (cf. Coulson 2005), it has not as yet been studied in specialized language. In this paper, we show how it can be applied to harmful algal bloom in the field of marine biology.
Multilevel preconditioners for discontinuous Galerkin approximations of elliptic problems with jump coefficients
Authors: Ayuso de Dios Blanca , Holst Michael , Zhu Yunrong , Zikatanov Ludmil
Published: October 2013

We introduce and analyze two-level and multilevel preconditioners for a family of Interior Penalty (IP) discontinuous Galerkin (DG) discretizations of second order elliptic problems with large jumps in the diffusion coefficient. Our approach to IPDG-type methods is based on a splitting of the DG space into two components that are orthogonal in the energy inner product naturally induced by the methods. As a result, the methods and their analysis depend in a crucial way on the diffusion coefficient of the problem. The analysis of the proposed preconditioners is presented for both symmetric and non-symmetric IP schemes; dealing simultaneously with the jump in the diffusion coefficient and the non-nested character of the relevant discrete spaces presents additional difficulties in the analysis, which precludes a simple extension of existing results. However, we are able to establish robustness (with respect to the diffusion coefficient) and near-optimality (up to a logarithmic term depending on the mesh size) for both two-level and BPX-type preconditioners, by using a more refined Conjugate Gradient theory. Useful by-products of the analysis are the supporting results on the construction and analysis of simple, efficient and robust two-level and multilevel preconditioners for non-conforming Crouzeix-Raviart discretizations of elliptic problems with jump coefficients. Following the analysis, we present a sequence of detailed numerical results which verify the theory and illustrate the performance of the methods.
A question of taste
Authors: Mitchison T. J.
Published: October 2013

A career in science is shaped by many factors, one of the most important being our tastes in research. These typically form early and are shaped by subsequent successes and failures. My tastes run to microscopes, chemistry, and spatial organization of cytoplasm. I will try to identify where they came from, how they shaped my career, and how they continue to evolve. My hope is to inspire young scientists to identify and celebrate their own unique tastes.
Creating opportunities for science PhDs to pursue careers in high school education
Authors: Doyle Kari M. H. , Vale Ronald D.
Published: October 2013

The United States is confronting important challenges at both the early and late stages of science education. At the level of K–12 education, a recent National Research Council report (Successful K–12 STEM Education) proposed a bold restructuring of how science is taught, moving away from memorizing facts and emphasizing hands-on, inquiry-based learning and a deeper understanding of the process of science. At higher levels of training, limited funding for science is leading PhDs to seek training and careers in areas other than research. Might science PhDs play a bigger role in the future of K–12 education, particularly at the high school level? We explore this question by discussing the roles that PhDs can play in high school education and the current and rather extensive barriers to PhDs entering the teaching profession and finally suggest ways to ease the entrance of qualified PhDs into high school education.
Investigating the rheological properties of native plant latex
Authors: Bauer Georg , Friedrich Christian , Gillig Carina , Vollrath Fritz , Speck Thomas , Holland Chris
Published: October 2013

Plant latex, the source of natural rubber, has been of interest to mankind for millennia, with much of the research on its rheological (flow) properties focused towards industrial application. However, little is known regarding the rheology of the native material as produced by the plant, a key factor in determining latex's biological functions. In this study, we outline a method for rheological comparison between native latices that requires a minimum of preparatory steps. Our approach provides quantitative insights into the coagulation mechanisms of
Euphorbia
and
Ficus
latex allowing interpretation within a comparative evolutionary framework. Our findings reveal that in laboratory conditions both latices behave like non-Newtonian materials with the coagulation of
Euphorbia
latex being mediated by a slow evaporative process (more than 60 min), whereas
Ficus
appears to use additional biochemical components to increase the rate of coagulation (more than 30 min). Based on these results, we propose two different primary defensive roles for latex in these plants: the delivery of anti-herbivory compounds (
Euphorbia
) and rapid wound healing (
Ficus
).
Climate, not Aboriginal landscape burning, controlled the historical demography and distribution of fire-sensitive conifer populations across Australia
Authors: Sakaguchi Shota , Bowman David M. J. S. , Prior Lynda D. , Crisp Michael D. , Linde Celeste C. , Tsumura Yoshihiko , Isagi Yuji
Published: October 2013

Climate and fire are the key environmental factors that shape the distribution and demography of plant populations in Australia. Because of limited palaeoecological records in this arid continent, however, it is unclear as to which factor impacted vegetation more strongly, and what were the roles of fire regime changes owing to human activity and megafaunal extinction (sinceca50 kya). To address these questions, we analysed historical genetic, demographic and distributional changes in a widespread conifer species complex that paradoxically grows in fire-prone regions, yet is very sensitive to fire. Genetic demographic analysis showed that the arid populations experienced strong bottlenecks, consistent with range contractions during the Last Glacial Maximum (ca20 kya) predicted by species distribution models. In southern temperate regions, the population sizes were estimated to have been mostly stable, followed by some expansion coinciding with climate amelioration at the end of the last glacial period. By contrast, in the flammable tropical savannahs, where fire risk is the highest, demographic analysis failed to detect significant population bottlenecks. Collectively, these results suggest that the impact of climate change overwhelmed any modifications to fire regimes by Aboriginal landscape burning and megafaunal extinction, a finding that probably also applies to other fire-prone vegetation across Australia.
Rubrobacter aplysinae sp. nov., isolated from the marine sponge Aplysina aerophoba
Authors: Kämpfer Peter , Glaeser Stefanie P. , Busse Hans-Jürgen , Abdelmohsen Usama Ramadan , Hentschel Ute
Published: October 2013

A Gram-stain-positive, non-spore-forming bacterium (strain RV113T) was isolated from the marine sponge Aplysina aerophoba. 16S rRNA gene sequence analysis showed that strain RV113T belongs to the genus

Rubrobacter

, and is related most closely to

Rubrobacter bracarensis

VF70612_S1T (96.9 % similarity) and more distantly related (<93 %) to all other species of the genus

Rubrobacter

. The peptidoglycan diamino acid was lysine. Strain RV113T exhibited a quinone system with menaquinone MK-8 as the predominant compound. The polar lipid profile of strain RV113T consisted of the major compounds phosphatidylglycerol and two unidentified phosphoglycolipids. The major fatty acid was anteiso-C17 : 0ω9c. These chemotaxonomic traits are in agreement with those of other species of the genus

Rubrobacter

. The results of physiological and biochemical tests allowed the clear phenotypic differentiation of strain RV113T from all recognized

Rubrobacter

species. Strain RV113T is thus considered to represent a novel species, for which the name

Rubrobacter

aplysinae sp. nov. is proposed. The type strain is RV113T ( = DSM 27440T = CECT 8425T).
Kordia jejudonensis sp. nov., isolated from the junction between the ocean and a freshwater spring, and emended description of the genus Kordia
Authors: Park Sooyeon , Jung Yong-Taek , Yoon Jung-Hoon
Published: October 2013

A Gram-staining-negative, aerobic, non-spore-forming, non-flagellated, non-gliding and rod-shaped bacterial strain, SSK3-3T, was isolated from the zone where the ocean and a freshwater spring meet at Jeju island, South Korea. Strain SSK3-3T grew optimally at 30 °C, at pH 7.0–8.0 and in the presence of 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain SSK3-3T clustered with the type strains of species of the genus

Kordia

, with which it exhibited 96.5–97.2 % 16S rRNA gene sequence similarity. Sequence similarities to the type strains of other recognized species were less than 92.2 %. Strain SSK3-3T contained MK-6 as the predominant menaquinone and iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as the major fatty acids. The major polar lipids of strain SSK3-3T were phosphatidylethanolamine, one unidentified lipid and one unidentified glycolipid. The DNA G+C content of strain SSK3-3T was 34.9 mol% and the mean DNA–DNA relatedness with

Kordia periserrulae

KACC 14311T was 12 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain SSK3-3T is separate from other species of the genus

Kordia

. On the basis of the data presented, strain SSK3-3T is considered to represent a novel species of the genus

Kordia

, for which the name

Kordia

jejudonensis sp. nov. is proposed. The type strain is SSK3-3T ( = KCTC 32426T = CECT 8368T). An emended description of the genus

Kordia

is also provided.
Sulfur oxidation to sulfate coupled with electron transfer to electrodes by Desulfuromonas strain TZ1
Authors: Zhang Tian , Bain Timothy S. , Barlett Melissa A. , Dar Shabir A. , Snoeyenbos-West Oona L. , Nevin Kelly P. , Lovley Derek R.
Published: October 2013

Microbial oxidation of elemental sulfur with an electrode serving as the electron acceptor is of interest because this may play an important role in the recovery of electrons from sulfidic wastes and for current production in marine benthic microbial fuel cells. Enrichments initiated with a marine sediment inoculum, with elemental sulfur as the electron donor and a positively poised (+300 mV versus Ag/AgCl) anode as the electron acceptor, yielded an anode biofilm with a diversity of micro-organisms, including Thiobacillus, Sulfurimonas, Pseudomonas, Clostridium and Desulfuromonas species. Further enrichment of the anode biofilm inoculum in medium with elemental sulfur as the electron donor and Fe(III) oxide as the electron acceptor, followed by isolation in solidified sulfur/Fe(III) medium yielded a strain of Desulfuromonas, designated strain TZ1. Strain TZ1 effectively oxidized elemental sulfur to sulfate with an anode serving as the sole electron acceptor, at rates faster than Desulfobulbus propionicus, the only other organism in pure culture previously shown to oxidize S° with current production. The abundance of Desulfuromonas species enriched on the anodes of marine benthic fuel cells has previously been interpreted as acetate oxidation driving current production, but the results presented here suggest that sulfur-driven current production is a likely alternative.
Effects of conserved residues and naturally occurring mutations on Mycobacterium tuberculosis RecG helicase activity
Authors: Zegeye Ephrem Debebe , Balasingham Seetha V. , Laerdahl Jon K. , Homberset Håvard , Kristiansen Per E. , Tønjum Tone
Published: October 2013

RecG is a helicase that is conserved in nearly all bacterial species. The prototypicalEscherichia coliRecG promotes regression of stalled replication forks, participates in DNA recombination and DNA repair, and prevents aberrant replication.Mycobacterium tuberculosisRecG (RecGMtb) is a DNA-dependent ATPase that unwinds a variety of DNA substrates, although its preferred substrate is a Holliday junction. Here, we performed site-directed mutagenesis of selected residues in the wedge domain and motifs Q, I, Ib and VI of RecGMtb. Three of the 10 substitution mutations engineered were detected previously as naturally occurring SNPs in the gene encoding RecGMtb. Alanine substitution mutations at residues Q292, F286, K321 and R627 abolished the RecGMtbunwinding activity, whilst RecGMtbF99A, P285S and T408A mutants exhibited ~25–50 % lower unwinding activity than WT. We also found that RecGMtbbound ATP in the absence of a DNA cofactor.
2-(2-Chloro-8-methylquinolin-3-yl)-4-phenyl-1,2-dihydroquinazoline
Authors: Derabli Chamseddine , Boulcina Raouf , Bouacida Sofiane , Merazig Hocine , Debache Abdelmadjid
Published: October 2013

In the title compound, C24H18ClN3, the dihydroquinazoline and methyl-substituted quinoline benzene rings make a dihedral angle of 78.18 (4)° and form dihedral angles of 45.91 (5) and 79.80 (4)°, respectively, with the phenyl ring. The dihedral angle between the phenyl ring of dihydroquinazoline and the methyl-substituted benzene ring of quinoline is 78.18 (4)°. The crystal packing can be described as crossed layers parallel to the (011) and (0-11) planes. The structure features N—H...N hydrogen bonds and π–π interactions [centroid–centroid distance between phenyl rings = 3.7301 (9) Å].
Techno economic systems and excessive consumption: a political economy of ‘pathological’ gambling
Authors: Reith Gerda
Published: October 2013

This article argues that gambling is a paradigmatic form of consumption that captures the intensified logic at the heart of late modern capitalist societies. As well as a site of intensified consumption, it claims that gambling has also become the location of what has been described as a new form of ‘social pathology’ related to excess play. Drawing on Castells' (1996) notion of techno‐economic systems, it explores the ways that intersections between technology, capital and states have generated the conditions for this situation, and critiques the unequal distribution of gambling environments that result.

It argues that, while the products of these systems are consumed on a global scale, the risks associated with them tend to be articulated in bio‐psychological discourses of ‘pathology’ which are typical of certain types of knowledge that have salience in neo‐liberal societies, and which work to conceal wider structural relationships. We argue that a deeper understanding of the political and cultural economy of gambling environments is necessary, and provide a synoptic overview of the conditions upon which gambling expansion is based. This perspective highlights parallels with the wider global economy of finance capital, as well as the significance of intensified consumption, of which gambling is an exemplary instance. It also reveals the existence of a geo‐political dispersal of ‘harms’, conceived as deteriorations of financial, temporal and social relationships, which disproportionately affect vulnerable social groups. From this, we urge an understanding of commercial gambling based on a critique of the wider social body of gambling environments within techno economic systems, rather than the (flawed) individual bodies within them.
Permethrin resistance variation and susceptible reference line isolation in a field population of the mosquito, Culex quinquefasciatus (Diptera: Culicidae)
Authors: Yang Ting , Liu Nannan
Published: October 2013

This study examines the genetic variations and mechanisms involved in the development of permethrin resistance in individual mosquitoes from a field population of Culex quinquefasciatus, HAmCqG0, and characterizes susceptible reference lines of mosquitoes with a similar genetic background to the field HAmCqG0 strain. Six upregulated cytochrome P450 genes, CYP9M10, CYP9J34, CYP6P14, CYP9J40, CYP6AA7, and CYP4C52v1, previously identified as being upregulated in the larvae of resistant HAmCqG8 mosquitoes were examined in the larvae of 3 strains (susceptible S‐Lab, parental HAmCqG0 and permethrin‐selected highly resistant HAmCqG8) and 8 HAmCqG0 single‐egg raft colonies, covering a range of levels of susceptibility/resistance to permethrin and exhibiting different variations in the expression of A and/or T alleles at the L‐to‐F kdr locus of the sodium channel. The 2 lines with the lowest tolerance to permethrin and bearing solely the susceptible A allele at the L‐to‐F kdr locus of the sodium channels, from colonies Cx_SERC5 and Cx_SERC8, showed lower or similar levels of all 6 of the P450 genes tested compared with the S‐Lab strain, suggesting that these 2 lines could be used as the reference mosquitoes in future studies characterizing insecticide resistance in HAmCq mosquitoes. This study also provides a detailed investigation of the mechanisms involved in insecticide resistance in individuals within a population: individuals with elevated levels of resistance to permethrin all displayed one or more potential resistance mechanisms–either elevated levels of P450 gene expression, or L‐to‐F mutations in the sodium channel, or both.
Brain GABA and glutamate levels in workers of two ant species (Hymenoptera: Formicidae): Interspecific differences and effects of queen presence/absence
Authors: Wnuk Andrzej , Kostowski Wojciech , Korczyńska Julita , Szczuka Anna , Symonowicz Beata , Bieńkowski Przemysław , Mierzejewski Paweł , Godzińska Ewa Joanna
Published: October 2013

Presence of amino acid neurotransmitters gamma‐aminobutyric acid (GABA) and glutamate (Glu) in ant brains was reported in very few studies. To learn more about factors influencing GABA and Glu levels in ant brains, we applied high‐performance liquid chromatography to measure levels of these compounds in single brains of workers of 2 ant species,Myrmica ruginodis(subfamily Myrmicinae) andFormica polyctena(subfamily Formicinae) taken from queenright/queenless colony fragments and tested in dyadic aggression tests consisting of an encounter with a nestmate, an alien conspecific or a small cricket. Brain glutamate levels were higher than those of GABA in both tested species. Brain GABA levels (in μmol/brain) and GABA : Glu ratio were higher inM. ruginodis(a submissive species) than inF. polyctena(a dominant, aggressive species) in spite of smaller brain weight ofM. ruginodis. Brain glutamate levels (in μmol/brain) did not differ between the tested species, which implies that glutamate concentration (in μmol/mg of brain tissue) was higher inM. ruginodis. Queen absence was associated with increased worker brain GABA levels inF. polyctena, but not inM. ruginodis. No significant effects of opponent type were discovered. As GABA agonists enhance friendly social behavior in rodents, we hypothesize that elevated brain GABA levels of orphaned workers ofF. polyctenafacilitate the adoption of a new queen. This is the first report providing information on GABA and glutamate levels in single ant brains and documenting the effects of queen presence/absence on brain levels of amino acid neurotransmitters in workers of social Hymenoptera.
Substantial skeletal muscle loss occurs during only 5 days of disuse
Authors: Wall B. T. , Dirks M. L. , Snijders T. , Senden J. M. G. , Dolmans J. , van Loon L. J. C.
Published: October 2013

Aim

The impact of disuse on the loss of skeletal muscle mass and strength has been well documented. Given that most studies have investigated muscle atrophy after more than 2 weeks of disuse, few data are available on the impact of shorter periods of disuse. We assessed the impact of 5 and 14 days of disuse on skeletal muscle mass, strength and associated intramuscular molecular signalling responses.

Methods

Twenty‐four healthy, young (23 ± 1 year) males were subjected to either 5 (n = 12) or 14 (n = 12) days of one‐legged knee immobilization using a full leg cast. Before and immediately after the immobilization period, quadriceps muscle cross‐sectional area (CSA), leg lean mass and muscle strength were assessed, and biopsies were collected from the vastus lateralis.

Results

Quadriceps muscle CSA declined from baseline by 3.5 ± 0.5 (P < 0.0001) and 8.4 ± 2.8% (P < 0.001), leg lean mass was reduced by 1.4 ± 0.7 (P = 0.07) and 3.1 ± 0.7% (P < 0.01) and strength was decreased by 9.0 ± 2.3 (P < 0.0001) and 22.9 ± 2.6% (P < 0.001) following 5 and 14 days of immobilization respectively. Muscle myostatin mRNA expression doubled following immobilization (P < 0.05) in both groups, while the myostatin precursor isoform protein content decreased after 14 days only (P < 0.05). Muscle MAFBx mRNA expression increased from baseline by a similar magnitude following either 5 or 14 days of disuse, whereas MuRF1 mRNA expression had increased significantly only after 5 days.

Conclusion

We conclude that even short periods of muscle disuse can cause substantial loss of skeletal muscle mass and strength and are accompanied by an early catabolic molecular signalling response.
Testing the Efficiency of Simple Flakes, Retouched Flakes and Small Handaxes During Butchery
Authors: Galán A. B. , Domínguez‐Rodrigo M.
Published: October 2013

Handaxes, simple flakes and retouched flakes are three types of stone tools whose adaptive advantages are highly debated. Interpretations of these technologically different tools suggest that their adequacy for butchery is uneven. Although some experimentation has been made in this regard, further research is needed to understand which of these tool types are more efficient for butchery, thus granting adaptive advantages to the hominins who used them. The present experimental work shows that small handaxes provide higher return rates in butchery activities than simple and retouched flakes. Efficiency (measured in time) is significantly positive in handaxes compared to the other tools when defleshing. In contrast, when comparing the three stone tool sets (simple flakes, retouched flakes and handaxes), the return values obtained for disarticulation are very similar. This study also shows that cut marks do not occur randomly and are less stochastic than previously assumed. Defleshing leaves a preferential cluster of cut marks on mid‐shafts from long bones and even on these sections, depending on element type, patterns are statistically demonstrable.
High dose droperidol and QT prolongation: analysis of continuous 12‐lead recordings
Authors: Calver Leonie , Isbister Geoffrey K.
Published: October 2013

Aims

To investigate the QT interval after high dose droperidol using continuous 12‐lead Holter recordings.

Methods

This was a prospective study of patients given droperidol with a continuous Holter recording. Patients were recruited from the DORM II study which included patients with aggression presenting to the emergency department. Patients initially received 10 mg droperidol as part of a standardized sedation protocol. An additional 10 mg dose was given after 15 min if required and further doses at the clinical toxicologist's discretion. Continuous 12‐lead Holter recordings were obtained for 2–24 h utilizing high resolution digital recordings with automated QT interval measurement. Electrocardiograms were extracted hourly from Holter recordings. The QT interval was plotted against heart rate (HR) on the QT nomogram to determine if it was abnormal. QTcF (Fridericia's HR correction) was calculated and >500 ms was defined as abnormal.

Results

Forty‐six patients had Holter recordings after 10–40 mg droperidol and 316 QT–HR pairs were included. There were 32 abnormal QT measurements in four patients, three given 10 mg and one 20 mg. In three of the four patients QTcF >500 ms but only in one taking methadone was the timing of QTcF >500 ms consistent with droperidol dosing. Of the three other patients, one took amphetamines, one still had QT prolongation 24 h after droperidol and one took a lamotrigine overdose. No patient given >30 mg had a prolonged QT. There were no arrhythmias.

Conclusion

QT prolongation was observed with high dose droperidol. However, there was little evidence supporting droperidol being the cause and QT prolongation was more likely due to pre‐existing conditions or other drugs.
The mechanisms of action of plasma exchange
Authors: Reeves Hollie M. , Winters Jeffrey L.
Published: October 2013

The initial description of therapeutic plasma exchange (TPE) in an animal model was published almost 100 years ago. Since that time, this treatment has been applied to a wide variety of diseases but limited research has been published examining the mechanisms of action of TPE. The therapeutic effects of TPE could include the removal of pathological substances from the blood, such as monoclonal paraproteins and autoantibodies, as well as the replacement of deficient plasma components when plasma is used as a replacement fluid. Beyond these potential mechanisms, other possible mechanisms include possible alterations in lymphocyte proliferation and function that could sensitize these cells to immunosuppressant and chemotherapeutic agents and alterations in the immune system including changes in B and T cell numbers and activation, increased T suppressor function, and alteration in T‐helper cell type 1/2 (Th1/Th2) ratio. Much remains unknown about the mechanisms of action of TPE, indicating a need for basic research into this therapy.