bluuebunny/crossref_metadata_2025 huggingface dataset:
Analytical optimal pulse shapes obtained with the aid of genetic algorithms
Authors: Guerrero Rubén D. , Arango Carlos A. , Reyes Andrés
Published: September 2015

We propose a methodology to design optimal pulses for achieving quantum optimal control on molecular systems. Our approach constrains pulse shapes to linear combinations of a fixed number of experimentally relevant pulse functions. Quantum optimal control is obtained by maximizing a multi-target fitness function using genetic algorithms. As a first application of the methodology, we generated an optimal pulse that successfully maximized the yield on a selected dissociation channel of a diatomic molecule. Our pulse is obtained as a linear combination of linearly chirped pulse functions. Data recorded along the evolution of the genetic algorithm contained important information regarding the interplay between radiative and diabatic processes. We performed a principal component analysis on these data to retrieve the most relevant processes along the optimal path. Our proposed methodology could be useful for performing quantum optimal control on more complex systems by employing a wider variety of pulse shape functions.
Electrocoalescence of a drop pair
Authors: Mhatre Sameer , Deshmukh Shivraj , Thaokar Rochish. M.
Published: September 2015

The interaction and coalescence of a freely suspended drop pair, aligned in a uniform DC electric field is investigated using experiments, analytical theory, and numerical calculations (boundary element method (BEM)). The systems considered are a pair of perfect conductor drops in a perfect dielectric fluid and a pair of leaky dielectric drops suspended in another leaky dielectric fluid. The applied electric field induces a dipole in the drops that form a pair, leading to their approach and subsequent merger. The study focuses on the drop approach and the film drainage stages of drop-drop electrocoalescence. The shapes and motion predicted using BEM are in good agreement with the experimental results and analytical theory.
Low-energy electron holographic imaging of individual tobacco mosaic virions
Authors: Longchamp Jean-Nicolas , Latychevskaia Tatiana , Escher Conrad , Fink Hans-Werner
Published: September 2015

Modern structural biology relies on Nuclear Magnetic Resonance (NMR), X-ray crystallography, and cryo-electron microscopy for gaining information on biomolecules at nanometer, sub-nanometer, or atomic resolution. All these methods, however, require averaging over a vast ensemble of entities, and hence knowledge on the conformational landscape of an individual particle is lost. Unfortunately, there are now strong indications that even X-ray free electron lasers will not be able to image individual molecules but will require nanocrystal samples. Here, we show that non-destructive structural biology of single particles has now become possible by means of low-energy electron holography. As an example, individual tobacco mosaic virions deposited on ultraclean freestanding graphene are imaged at 1 nm resolution revealing structural details arising from the helical arrangement of the outer protein shell of the virus. Since low-energy electron holography is a lens-less technique and since electrons with a deBroglie wavelength of approximately 1 Å do not impose radiation damage to biomolecules, the method has the potential for Angstrom resolution imaging of single biomolecules.
Interatomic scattering in energy dependent photoelectron spectra of Ar clusters
Authors: Patanen M. , Benkoula S. , Nicolas C. , Goel A. , Antonsson E. , Neville J. J. , Miron C.
Published: September 2015

Soft X-ray photoelectron spectra of Ar 2p levels of atomic argon and argon clusters are recorded over an extended range of photon energies. The Ar 2p intensity ratios between atomic argon and clusters’ surface and bulk components reveal oscillations similar to photoelectron extended X-ray absorption fine structure signal (PEXAFS). We demonstrate here that this technique allows us to analyze separately the PEXAFS signals from surface and bulk sites of free-standing, neutral clusters, revealing a bond contraction at the surface.
Solvent controlled ion association in structured copolymers: Molecular dynamics simulations in dilute solutions
Authors: Aryal Dipak , Perahia Dvora , Grest Gary S.
Published: September 2015

Tailoring the nature of individual segments within ion containing block co-polymers is one critical design tool to achieve desired properties. The local structure including the size and distribution of the ionic blocks, as well as the long range correlations, are crucial for their transport ability. Here, we present molecular dynamics simulations on the effects of varying the concentrations of the ionizable groups on the conformations of pentablock ionomer that consist of a center block of ionic sulfonated styrene tethered to polyethylene and terminated by a bulky substituted styrene in dilute solutions. Sulfonation fractions f (0 ≤ f ≤ 0.55), spanning the range from ionomer to polyelectrolytes, were studied. Results for the equilibrium conformation of the chains in water and a 1:1 mixture of cyclohexane and heptane are compared to that in implicit poor solvents with dielectric constants ε = 1.0 and 77.73. In water, the pentablock collapses with the sulfonated groups on the outer surface. As f increases, the ionic, center block increasingly segregates from the hydrophobic regions. In the 1:1 mixture of cyclohexane and heptane, the flexible blocks swell, while the center ionic block collapses for f > 0. For f = 0, all blocks swell. In both implicit poor solvents, the pentablock collapses into a nearly spherical shape for all f. The sodium counterions disperse widely throughout the simulation cell for both water and ε = 77.73, whereas for ε = 1.0 and mixture of cyclohexane and heptane, the counterions largely condense onto the collapsed pentablock.
Jeans instability of a dusty plasma with dust charge variations
Authors: Hakimi Pajouh H. , Afshari N.
Published: September 2015

The effect of the dust charge variations on the stability of a self-gravitating dusty plasma has been theoretically investigated. The dispersion relation for the dust-acoustic waves in a self-gravitating dusty plasma is obtained. It is shown that the dust charge variations have significant effects. It increases the growth rate of instability and the instability cutoff wavenumbers. It is found that by increasing the value of the ions temperature and the absolute value of the equilibrium dust charge, the cutoff wavenumber decreases and the stability region is extended.
Table-like magnetocaloric effect in Gd56Ni15Al27Zr2 alloy and its field independence feature
Authors: Agurgo Balfour E. , Ma Z. , Fu H. , Hadimani R. L. , Jiles D. C. , Wang L. , Luo Y. , Wang S. F.
Published: September 2015

In order to obtain “table-like” magnetocaloric effect (MCE), multiple-phase Gd56Ni15Al27Zr2 alloy was prepared by arc-melting followed by suck-casting method. Powder x-ray diffraction and calorimetric measurements reveal that the sample contains both glassy and crystalline phases. The fraction of the glassy phase is about 62%, estimated from the heat enthalpy of the crystallization. The crystalline phases, Gd2Al and GdNiAl further broadened the relatively wider magnetic entropy change (−ΔSM) peak of the amorphous phase, which resulted in the table-like MCE over a maximum temperature range of 52.5 K to 77.5 K. The plateau feature of the MCE was found to be nearly independent of the applied magnetic field from 3 T to 5 T. The maximum −ΔSM value of the MCE platforms is 6.0 J/kg K under applied magnetic field change of 5 T. Below 3 T, the field independence of the table-like feature disappears. The relatively large constant values of −ΔSM for the respective applied magnetic fields have promising applications in magnetic refrigeration using regenerative Ericsson cycle.
The influence of temperature induced phase transition on the energy storage density of anti-ferroelectric ceramics
Authors: Yi Jinqiao , Zhang Ling , Xie Bing , Jiang Shenglin
Published: September 2015

Anti-ferroelectric (AFE) composite ceramics of (Pb0.858Ba0.1La0.02Y0.008)(Zr0.65Sn0.3Ti0.05)O3-(Pb0.97La0.02)(Zr0.9Sn0.05Ti0.05)O3 (PBLYZST-PLZST) were fabricated by the conventional solid-state sintering process (CS), the glass-aided sintering (GAS), and the spark plasma sintering (SPS), respectively. The influence of the temperature induced phase transition on the phase structure, hysteresis loops, and energy storage properties of the composite ceramics were investigated in detail. The measured results of X-ray diffraction demonstrate that the composite ceramics exhibit the perovskite phases and small amounts of non-functional pyrochlore phases. Compared with the CS process, the GAS and SPS processes are proven more helpful to suppress the diffusion behaviors between the PBLYZST and PLZST phases according to the field emission scanning electron microscopy, thereby being able to improve the contribution of PBLYZST phase to the temperature stability of the orthogonal AFE phase. When the ambient temperature rises from 25 °C to 125 °C, CS and GAS samples have undergone a phase transition from orthorhombic AFE phase to tetragonal AFE phase, which results in a sharp decline in the energy storage density. However, the phase transition temperature of SPS samples is higher than 125 °C, and the energy storage density only slightly decreases due to the disorder of material microstructure caused by the high temperature. As a result, the SPS composite ceramics obtain a recoverable high energy storage density of 6.46 J/cm3 and the excellent temperature stability of the energy storage density of 1.16 × 10−2 J/°C·cm3, which is 1.29 × 10−2 J/°C·cm3 lower than that of CS samples and about 0.43 times as that of GAS samples.
Semiconductor-insulator transition in VO2 (B) thin films grown by pulsed laser deposition
Authors: Rúa Armando , Díaz Ramón D. , Lysenko Sergiy , Fernández Félix E.
Published: September 2015

Thin films of B-phase VO2 were grown by pulsed-laser deposition on glass and (100)-cut MgO substrates in a temperature range from 375 to 425 °C and at higher gas pressures than usual for this technique. The films were strongly oriented, with ab-planes parallel to the substrate surface. Detailed study of surface morphology through Atomic Force Microscopy images suggest significant differences in evolution as a function of growth temperature for films on the two types of substrates. Measurements of electrical conductivities through cooling-heating cycles from room temperature to 120 K showed changes of five orders of magnitude, with steeper changes between room temperature and ∼150 K, which corresponds with the extended and reversible phase transition known to occur for this material. At lower temperatures conductivities exhibited Arrhenius behavior, indicating that no further structural change was occurring and that conduction is thermally activated. In this lower temperature range, conductivity of the samples can be described by the near-neighbor hopping model. No hysteresis was found between the cooling and heating braches of the cycles, which is at variance with previous results published for VO2 (B). This apparent lack of hysteresis for thin films grown in the manner described and the large conductivity variation as a function of temperature observed for the samples suggests this material could be of interest for infrared sensing applications.
Discharge current modes of high power impulse magnetron sputtering
Authors: Wu Zhongzhen , Xiao Shu , Ma Zhengyong , Cui Suihan , Ji Shunping , Tian Xiubo , Fu Ricky K. Y. , Chu Paul K. , Pan Feng
Published: September 2015

Based on the production and disappearance of ions and electrons in the high power impulse magnetron sputtering plasma near the target, the expression of the discharge current is derived. Depending on the slope, six possible modes are deduced for the discharge current and the feasibility of each mode is discussed. The discharge parameters and target properties are simplified into the discharge voltage, sputtering yield, and ionization energy which mainly affect the discharge plasma. The relationship between these factors and the discharge current modes is also investigated.
Emission characteristics of kerosene-air spray combustion with plasma assistance
Authors: Liu Xingjian , He Liming , Zeng Hao , Jin Tao , Chen Yi , Zhang Yihan , Liu Pengfei
Published: September 2015

A plasma assisted combustion system for combustion of kerosene-air mixtures was developed to study emission levels of O2, CO2, CO, and NOx. The emission measurement was conducted by Testo 350-Pro Flue Gas Analyzer. The effect of duty ratio, feedstock gas flow rate and applied voltage on emission performance has been analyzed. The results show that O2 and CO emissions reduce with an increase of applied voltage, while CO2 and NOx emissions increase. Besides, when duty ratio or feedstock gas flow rate decreases, the same emission results would appear. The emission spectrum of the air plasma of plasma assisted combustion actuator was also registered to analyze the kinetic enhancement effect of plasma, and the generation of ozone was believed to be the main factor that plasma makes a difference in our experiment. These results are valuable for the future optimization of kerosene-fueled aircraft engine when using plasma assisted combustion devices to exert emission control.
Responses of pea plants to elevated UV-B radiation at varying nutrient levels: N-metabolism, carbohydrate pool, total phenolics and yield
Authors: Singh Suruchi , Agrawal Shashi B. , Agrawal Madhoolika
Published: September 2015

The effects of elevated UV-B (280–315 nm) were assessed on nitrogen metabolism, carbohydrate pool, total phenolics, photosynthetic pigments, UV-B absorbing compounds, variables related to oxidative stress, biomass and yield of pea plants grown under various levels of NPK. The NPK levels assayed were: background NPK level (F0); recommended NPK (F1) and recommended NK + 1.5 × recommended P (F2) and the UV-B levels were: control (C) and elevated (T). The responses of T plants varied with different combinations of NPK. Yield reduced under elevated UV-B at all NPK levels with maximum reduction in F0T and minimum reduction in F1T. Leghaemoglobin content was reduced under elevated UV-B at all NPK levels. Maximum increase in malondialdehyde content recorded in F0T plants corresponded with higher superoxide and hydrogen peroxide contents. Nitrite reductase activity decreased significantly under UV-B at all NPK levels, but nitrate reductase activity increased significantly in F1T and F2T. Maximum reduction in C : N ratio of leaves in F2T plants suggests competition between sucrose synthesis and nitrate reduction under additional P level. The study concludes that application of recommended level of NPK caused least changes in N metabolism leading to minimum yield losses due to elevated UV-B stress.
Seasonal predictability of summer fires in a Mediterranean environment
Authors: Marcos Raül , Turco Marco , Bedía Joaquín , Llasat Maria Carmen , Provenzale Antonello
Published: September 2015

In this study we explore the seasonal predictability of summer wildfires in a Mediterranean region (north-eastern Spain), developing a multiple linear regression model with antecedent and current-summer drought indices (Standardised Precipitation Index; and Standardised Precipitation Evapotranspiration Index). This model is based on the assumption that large summer fires in Mediterranean environments are favoured by current-summer drought (proxy for the climatic factors that affect fuel flammability) and by antecedent wet conditions (proxies for the climatic factors influencing fine fuel availability and connectivity). We test three forecast systems based on (i) seasonal European Centre for Medium-Range Weather Forecasts (ECMWF) System-4 forecasts; (ii) persistence and (iii) climatology. These approaches are evaluated through a leave-one-out cross-validation over the period 1983–2012. The climatology forecast, which considers only antecedent wet or dry conditions with a time lag of 2 years, shows some amount of skill in simulating above- or below-normal summer fire activity. ECMWF System-4 proves to be of limited added value with respect to the climatology forecast. Finally, the persistence forecast, which is driven by antecedent conditions and drought conditions just before the start of the fire season, allows more satisfactory results (correlation of 0.49). The results suggest that long-term forecasts of above-normal burned area are feasible in Catalonia (north-eastern Spain), information that could be potentially applied also to other Mediterranean-type regions.
The Complexity and Variability of Self-Deprecation in Korean Conversation
Authors: Kim Mary Shin
Published: September 2015

Drawing on a corpus of telephone conversational data, this study examines a collection of self-deprecations in Korean conversations. Detailed analyses of self-deprecations in larger fragments than minimal adjacency pair sequences illustrate the multifaceted nature of self-deprecation. Self-deprecation entails not only deprecatory assessments, but complaint or trouble talk about one’s shortcomings, reenactment of experiences or moments that support the deprecation, and discussion of how to remedy problems. The study further shows that self-deprecation is not a solitary but an interactionally organized practice. The speaker’s repeated self-deprecations elicit a series of different responses from the recipient, such as positive reframing, downgrading the deprecator’s problem, and recommending solutions to the deprecator’s problem. Many instances of self-deprecation suggest that it can be an important resource for building motivation, responsibility, and a sense of affiliation and solidarity with other social members.
mTOR and differential activation of mitochondria orchestrate neutrophil chemotaxis
Authors: Bao Yi , Ledderose Carola , Graf Amelie F. , Brix Bianca , Birsak Theresa , Lee Albert , Zhang Jingping , Junger Wolfgang G.
Published: September 2015

Neutrophils use chemotaxis to locate invading bacteria. Adenosine triphosphate (ATP) release and autocrine purinergic signaling via P2Y2 receptors at the front and A2a receptors at the back of cells regulate chemotaxis. Here, we examined the intracellular mechanisms that control these opposing signaling mechanisms. We found that mitochondria deliver ATP that stimulates P2Y2 receptors in response to chemotactic cues, and that P2Y2 receptors promote mTOR signaling, which augments mitochondrial activity near the front of cells. Blocking mTOR signaling with rapamycin or PP242 or mitochondrial ATP production (e.g., with CCCP) reduced mitochondrial Ca2+ uptake and membrane potential, and impaired cellular ATP release and neutrophil chemotaxis. Autocrine stimulation of A2a receptors causes cyclic adenosine monophosphate accumulation at the back of cells, which inhibits mTOR signaling and mitochondrial activity, resulting in uropod retraction. We conclude that mitochondrial, purinergic, and mTOR signaling regulates neutrophil chemotaxis and may be a pharmacological target in inflammatory diseases.
Sam37 is crucial for formation of the mitochondrial TOM–SAM supercomplex, thereby promoting β-barrel biogenesis
Authors: Wenz Lena-Sophie , Ellenrieder Lars , Qiu Jian , Bohnert Maria , Zufall Nicole , van der Laan Martin , Pfanner Nikolaus , Wiedemann Nils , Becker Thomas
Published: September 2015

Biogenesis of mitochondrial β-barrel proteins requires two preprotein translocases, the general translocase of the outer membrane (TOM) and the sorting and assembly machinery (SAM). TOM and SAM form a supercomplex that promotes transfer of β-barrel precursors. The SAM core complex contains the channel protein Sam50, which cooperates with Sam35 in precursor recognition, and the peripheral membrane protein Sam37. The molecular function of Sam37 has been unknown. We report that Sam37 is crucial for formation of the TOM–SAM supercomplex. Sam37 interacts with the receptor domain of Tom22 on the cytosolic side of the mitochondrial outer membrane and links TOM and SAM complexes. Sam37 thus promotes efficient transfer of β-barrel precursors to the SAM complex. We conclude that Sam37 functions as a coupling factor of the translocase supercomplex of the mitochondrial outer membrane.
A chimeric prokaryotic pentameric ligand–gated channel reveals distinct pathways of activation
Authors: Schmandt Nicolaus , Velisetty Phanindra , Chalamalasetti Sreevatsa V. , Stein Richard A. , Bonner Ross , Talley Lauren , Parker Mark D. , Mchaourab Hassane S. , Yee Vivien C. , Lodowski David T. , Chakrapani Sudha
Published: September 2015

Recent high resolution structures of several pentameric ligand–gated ion channels have provided unprecedented details of their molecular architecture. However, the conformational dynamics and structural rearrangements that underlie gating and allosteric modulation remain poorly understood. We used a combination of electrophysiology, double electron–electron resonance (DEER) spectroscopy, and x-ray crystallography to investigate activation mechanisms in a novel functional chimera with the extracellular domain (ECD) of amine-gated Erwinia chrysanthemi ligand–gated ion channel, which is activated by primary amines, and the transmembrane domain of Gloeobacter violaceus ligand–gated ion channel, which is activated by protons. We found that the chimera was independently gated by primary amines and by protons. The crystal structure of the chimera in its resting state, at pH 7.0 and in the absence of primary amines, revealed a closed-pore conformation and an ECD that is twisted with respect to the transmembrane region. Amine- and pH-induced conformational changes measured by DEER spectroscopy showed that the chimera exhibits a dual mode of gating that preserves the distinct conformational changes of the parent channels. Collectively, our findings shed light on both conserved and divergent features of gating mechanisms in this class of channels, and will facilitate the design of better allosteric modulators.
Sphingomonas hengshuiensis sp. nov., isolated from lake wetland
Authors: Wei Shuzhen , Wang Tingting , Liu Hongliang , Zhang Caifeng , Guo Jiping , Wang Qian , Liang Kuijing , Zhang Zhiqiang
Published: September 2015

A polyphasic taxonomic study was undertaken to establish the status of a novel bacterium, designated strain WHSC-8T, which was isolated from soil of Hengshui Lake Wetland Reserve in Hebei province, northern China. Colonies of this strain were yellow and cells were rod-shaped, polar-flagellated and obligately aerobic, exhibiting negative Gram reaction. The strain was able to grow at 0–1 % (w/v) NaCl, pH 5–10 and 20–35 °C, with optimal growth occurring at pH 7.0 and 28 °C without NaCl. Chemotaxonomic data revealed that strain WHSC-8T possesses ubiquinone Q-10 as the predominant respiratory quinone, C18 : 1ω7c, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) as the major fatty acids, and sym-homospermidine as the major polyamine. Sphingomonadaceae-specific sphingoglycolipid was detected in the polar lipid patterns. The G+C content of the genomic DNA was 68.7 mol%. All of the above characters corroborated the assignment of the novel strain to the genus Sphingomonas. Strain WHSC-8T shared less than 97.0 % 16S rRNA gene sequence similarity with the type strains of other species of the genus Sphingomonas, except for Sphingomonas asaccharolytica DSM 10564T (97.5 %). The low DNA–DNA relatedness value and distinct phenotypic and chemotaxonomic characteristics distinguished strain WHSC-8T from closely related species of the genus Sphingomonas. Therefore, strain WHSC-8T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas hengshuiensis sp. nov. is proposed. The type strain is WHSC-8T ( = KCTC 42455T = CCTCC AB 2015265T).
Tamaricihabitans halophyticus gen. nov., sp. nov., an endophytic actinomycete of the family Pseudonocardiaceae
Authors: Qin Sheng , Bai Juan-Luan , Wang Yu , Feng Wei-Wei , Yuan Bo , Sun Yong , Cao Cheng Liang , Ju Xiu-Yun , Huang Ying , Jiang Ji-Hong
Published: September 2015

A novel actinomycete strain, designated KLBMP 1356T, was isolated from the root of halophyte Tamarix chinensis Lour. collected from the coastal area of Jiangsu province, PR China. The isolate was characterized using a polyphasic approach. Comparative analysis of the 16S rRNA gene sequence indicated that strain KLBMP 1356T was phylogenetically related to members of the family Pseudonocardiaceae and formed a distinct monophyletic clade between the genera Amycolatopsis (93.1–94.7 % 16S rRNA gene sequence similarity), Prauserella (93.6–95.1 %) and Saccharomonospora (93.2–94.3 %). The isolate displayed long spore chains containing rod-shaped and smooth-surfaced spores. Strain KLBMP 1356T contained meso-diaminopimelic acid as the diagnostic diamino acid, and galactose, arabinose and glucose as the whole-cell sugars. The major menaquinone was MK-9(H4) and the fatty acid profile was characterized by the predominance of iso-C16 : 0, C17 : 1ω8c, C17 : 1ω6c and C17 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, unknown aminophospholipids and an unknown glycolipid. Mycolic acids were not present. The G+C content of the genomic DNA was 67.2 mol%. On the basis of the evidence from this polyphasic study, strain KLBMP 1356T is considered to represent a novel species of a new genus in the family Pseudonocardiaceae, for which the name Tamaricihabitans halophyticus gen. nov., sp. nov. is proposed. The type strain of the type species is KLBMP 1356T ( = DSM 45765T = NBRC 109361T).
Bradyrhizobium guangdongense sp. nov. and Bradyrhizobium guangxiense sp. nov., isolated from effective nodules of peanut
Authors: Li Yong Hua , Wang Rui , Zhang Xiao Xia , Young J. Peter. W. , Wang En Tao , Sui Xin Hua , Chen Wen Xin
Published: September 2015

Seven slow-growing rhizobia isolated from effective nodules of Arachis hypogaea were assigned to the genus Bradyrhizobium based on sharing 96.3–99.9 % 16S rRNA gene sequence similarity with the type strains of recognized Bradyrhizobium species. Multilocus sequence analysis of glnII, recA, gyrB and dnaK genes indicated that the seven strains belonged to two novel species represented by CCBAU 51649T and CCBAU 53363T. Strain CCBAU 51649T shared 94, 93.4, 92.3 and 94.9 % and CCBAU 53363T shared 91.4, 94.5, 94.6 and 97.7 % sequence similarity for the glnII, recA, gyrB and dnaK genes, respectively, with respect to the closest related species Bradyrhizobium manausense BR 3351T and Bradyrhizobium yuanmingense CCBAU 10071T. Summed feature 8 and C16 : 0 were the predominant fatty acid components for strains CCBAU 51649T and CCBAU 53363T. DNA–DNA hybridization and analysis of phenotypic characteristics also distinguished these strains from the closest related Bradyrhizobium species. The strains formed effective nodules on Arachis hypogaea, Lablab purpureus and Aeschynomene indica, and they had identical nodA genes to Bradyrhizobium sp. PI237 but were phylogenetically divergent from other available nodA genes at less than 66 % similarity. Based in these results, strains CCBAU 51649T ( = CGMCC 1.15034T = LMG 28620T) and CCBAU 53363T ( = CGMCC 1.15035T = LMG 28621T) are designated the type strains of two novel species, for which the names Bradyrhizobium guangdongense sp. nov. and Bradyrhizobium guangxiense sp. nov. are proposed, respectively.
Zooshikella marina sp. nov. a cycloprodigiosin- and prodigiosin-producing marine bacterium isolated from beach sand
Authors: Ramaprasad E. V. V. , Bharti Dave , Sasikala Ch. , Ramana Ch. V.
Published: September 2015

A red-pigmented bacterium producing a metallic green sheen, designated strain JC333T, was isolated from a sand sample collected from Shivrajpur–Kachigad beach, Gujarat, India. Phylogenetic analyses based on the 16S rRNA gene sequence of strain JC333T showed highest sequence similarity to Zooshikella ganghwensis JC2044T (99.24 %) and less than 91.94 % similarity with other members of the class Gammaproteobacteria. DNA–DNA hybridizations between JC333T and Z. ganghwensis JC2044T showed low relatedness values of 19 ± 1.3 % (reciprocal 21 ± 2.2 %). The major respiratory quinone was ubiquinone-9 (Q9) and the polar lipid profile was composed of the major components diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminophospholipid and an unidentified lipid. The presence of C16 : 1ω7c/C16 : 1ω6c, C16 : 0, C18 : 1ω7c and C12 : 0 as major fatty acids supported the affiliation of strain JC333T to the genus Zooshikella. Prodigiosin, cycloprodigiosin and eight other prodigiosin analogues were the pigments of JC333T. Characterization based on 16S rRNA gene sequence analysis, physiological parameters, pigment analysis, ubiquinone, and polar lipid and fatty acid compositions revealed that JC333T represents a novel species of the genus Zooshikella, for which the name Zooshikella marina sp. nov. is proposed. The type strain is JC333T ( = KCTC 42659T = LMG 28823T).
CRISPR/Cas9-Assisted Transformation-Efficient Reaction (CRATER), a novel method for selective transformation
Authors: Rothschild L. J. , Greenberg D. T. , Takahashi J. R. , Thompson K. A. , Maheshwari A. J. , Kent R. E. , McCutcheon G. , Shih J. D. , Calvet C. , Devlin T. D. , Ju T. , Kunin D. , Lieberman E. , Nguyen T. , Tran F. G. , Xiang D. , Fujishima K.
Published: September 2015

The CRISPR/Cas9 system has revolutionized genome editing by providing unprecedented DNA-targeting specificity. Here we demonstrate that this system can be applied to facilitate efficient plasmid selection for transformation as well as selective gene insertion into plasmid vectors by cleaving unwanted plasmid byproducts after restriction enzyme digestion and ligation. Using fluorescent and chromogenic proteins as reporters, we demonstrate that CRISPR/Cas9 cleavage excludes unwanted ligation byproducts and increases transformation efficiency of desired inserts from 20% up to 97% ± 3%. This CRISPR/Cas9-Assisted Transformation-Efficient Reaction (CRATER) protocol is a novel, inexpensive, and convenient method for obtaining specific cloning products.
Investigation of a CPG-array CdZnTe γ-ray imaging detector with single collecting electrodes readout
Authors: Ma Yuedong , Xiao Shali , Yang Guoqiang , Zhang Liuqiang
Published: September 2015

The single-electrode readout method has been applied to a coplanar grid (CPG) array CdZnTe detector in order to halve the number of preamplifiers previously needed and to facilitate imaging applications of CPG detectors. A method of predetermining the width of the optimum collecting electrodes has also been proposed, using the calculated optimum relative gain factorG. Meanwhile, a detailed process for calculating the charge induction efficiency (CIE) is presented. To simplify the calculation process, the computational formula of the CIE was deduced through the integration of the weighting potential. For performance evaluation, a 2 × 2 CPG-array CdZnTe detector was elaborately designed and tested with137Cs at 662 keV. Experimental results showed the capability of using the CPG-array CdZnTe detector with single collecting electrode readout for γ-ray imaging applications, with the same complexity of associated readout electronics as that of the pixelated CdZnTe detectors.
A miniature closed-circle flow cell for high photon flux X-ray scattering experiments
Authors: Sahle Ch. J. , Henriquet C. , Schroer M. A. , Juurinen I. , Niskanen J. , Krisch M.
Published: September 2015

A closed-circle miniature flow cell for high X-ray photon flux experiments on radiation-sensitive liquid samples is presented. The compact cell is made from highly inert material and the flow is induced by a rotating magnetic stir bar, which acts as a centrifugal pump inside the cell. The cell is ideal for radiation-sensitive yet precious or hazardous liquid samples, such as concentrated acids or bases. As a demonstration of the cell's capabilities, X-ray Raman scattering spectroscopy data on the oxygenK-edge of liquid water under ambient conditions are presented.
Divergence or convergence: paradoxes in corporate governance?
Authors: Chhillar Palka , Lellapalli Ramana Venkata
Published: September 2015

Purpose

– This review paper aims to compare the various dimensions in the finance literature pertaining to the Anglo-Saxon Model (Stockholder Model) prevalent in the USA and the UK with the German Model (Stakeholder Model) of corporate governance prevalent in Germany and continental Europe. The present study identifies different strands of research on the various dimensions of these models, along with aspects of governance in emerging economies and the phenomenon of the convergence of these governance mechanisms.

Design/methodology/approach

– The literature review on corporate governance models has been carried out on the themes of internal and external governance mechanisms. The review considers agency theory along with principal–principal (PP) conflicts as the fundamental blocks explaining the need for governance structures.

Findings

– The traditional models of governance, along with the incorporation of PP conflicts, will result in a hybrid model inculcating the best of both the traditional models. However, convergence in the true sense may not be possible owing to fundamental differences pertaining to cultural, economic, legal and socio-economic aspects of the firm.

Originality/value

– This paper proposes a framework incorporating the interplay of managerial talent and controlling shareholders to understand the governance system that may be applicable for firms in emerging economies.
Dynamics of random coupled structures through the wave finite element method
Authors: Ben Souf Mohamed Amine , Ichchou Mohamed , Bareille Olivier , Bouhaddi Noureddine , Haddar Mohamed
Published: September 2015

Purpose

– The purpose of this paper is to develop a new formulation using spectral approach, which can predict the wave behavior to uncertain parameters in mid and high frequencies.

Design/methodology/approach

– The work presented is based on a hybridization of a spectral method called the “wave finite element (WFE)” method and a non-intrusive probabilistic approach called the “polynomial chaos expansion (PCE).” The WFE formulation for coupled structures is detailed in this paper. The direct connection with the conventional finite element method allows to identify the diffusion relation for a straight waveguide containing a mechanical or geometric discontinuity. Knowing that the uncertainties play a fundamental role in mid and high frequencies, the PCE is applied to identify uncertainty propagation in periodic structures with periodic uncertain parameters. The approach proposed allows the evaluation of the dispersion of kinematic and energetic parameters.

Findings

– The authors have found that even though this approach was originally designed to deal with uncertainty propagation in structures it can be competitive with its low time consumption. The Latin Hypercube Sampling (LHS) is also employed to minimize CPU time.

Originality/value

– The approach proposed is quite new and very simple to apply to any periodic structures containing variabilities in its mechanical parameters. The Stochastic Wave Finite Element can predict the dynamic behavior from wave sensitivity of any uncertain media. The approach presented is validated for two different cases: coupled waveguides with and without section modes. The presented results are verified vs Monte Carlo simulations.
Influence of wiki participation on transnational collaboration learning anxiety in middle school students
Authors: Ku David Tawei , Chen Nancy Lanhui
Published: September 2015

Purpose

– The purpose of this paper is to investigate the Wiki and its influence on the anxiety produced during cross-cultural web-based collaborative learning sessions.

Design/methodology/approach

– In total, 49 high school students participated in transnational collaborative learning and engaged in a one-month Google Wiki activity. A transnational collaborative learning anxiety inventory was used to measure the anxiety of the participants, which included the dimensions of social anxiety, foreign language anxiety, and computer anxiety. In addition, platform usage records were compiled using Google Wiki user records and participation process checklists. Relative data derived from these two items were compared with the questionnaire data.

Findings

– The results indicated that participants who had experience with Wiki transnational collaborative learning exhibited significantly reduced SA and FLA. Participation process and user records revealed that embedding videos; responding to content created by others; proofreading and editing the content of others; updating layouts; underlining text, changing the font, and color coding; and increasing the number of edits reduced FLA. The number of times edits and responses were produced was correlated with decreases in SA.

Originality/value

– The causes and effects of transnational collaborative learning have concurrently received attention. However, studies on Wiks and their impact on the anxiety produced during cross-cultural Web-based collaborative learning are limited. Therefore, Google Wiki was used in this study as the medium through which the effects of Wiki participation on anxiety resulting from transnational collaborative learning were explored.
Seismoelectric measurements in a porous quartz‐sand sample with anisotropic permeability
Authors: Zhu Zhenya , Toksӧz M.N. , Zhan Xin
Published: September 2015

Seismoelectric coupling coefficients are difficult to predict theoretically because they depend on a large numbers of rock properties, including porosity, permeability, tortuosity, etc. The dependence of the coupling coefficient on rock properties such as permeability requires experimental data. In this study, we carry out a set of laboratory measurements to determine the dependence of seismoelectric coupling coefficient on permeability. We use both an artificial porous “sandstone” sample, with cracks, built using quartz‐sand and Berea sandstone samples. The artificial sample is a cube with 39% porosity. Its permeability levels are anisotropic: 14.7 D, 13.8 D, and 8.3 D in the x‐, y‐, and z‐directions, respectively. Seismoelectric measurements are performed in a water tank in the frequency range of 20 kHz–90 kHz. A piezoelectric P‐wave source is used to generate an acoustic wave that propagates through the sample from the three different (x, y, and z) directions. The amplitudes of the seismoelectric signal induced by the acoustic waves vary with the direction. The highest signal is in the direction of the highest permeability, and the lowest signal is in the direction of the lowest permeability. Since the porosity of the sample is constant, the results directly show the dependence of seismoelectric coefficients on permeability. Seismoelectric measurements with natural rocks are performed using Berea sandstone 500 and 100 samples. Because the Berea samples are nearly isotropic in permeability, the amplitudes of the seismoelectric signals induced in the different directions are the same within the measurement error. Because the permeability of Berea 500 is higher than that of Berea 100, the amplitude of the seismoelectric signals induced in Berea 500 is higher than those in Berea 100. To determine the relative contributions of porosity and permeability on seismoelectric conversion, we carried out an analysis, using Pride (1994) formulation and Kozeny–Carman relationship; the normalized amplitudes of seismoelectric coupling coefficients in three directions are calculated and compared with the experimental results. The results show that the seismoelectric conversion is related to permeability in the frequency range of measurements. This is an encouraging result since it opens the possibility of determining the permeability of a formation from seismoelectric measurements.
Gaus on Coercion and Welfare-State Capitalism: A Critique
Authors: Bou-Habib Paul
Published: September 2015

This article examines a novel line of argument in support of welfare-state capitalism proposed by Gerald Gaus. The novelty of Gaus’ argument lies in its contention that welfare-state capitalism can be justified on the basis of the contractualist mode of justification made famous by Rawls. Gaus argues that economic regimes, such as propertyowning democracy, are more coercive than welfare-state capitalism insofar as they require a greater degree of tax-imposed redistribution among citizens. Given the degree of coercion needed by these regimes, he contends that parties to a contract would not agree to them, whereas they would agree to welfare-state capitalism by virtue of the lesser degree of coercion it needs. It is argued in this article that Gaus fails to show that welfare-state capitalism is less coercive than property-owning democracy. Indeed, once one directs one’s attention towards those with the smallest range of valuable opportunities for action, there is reason to worry more about the coercion imposed by welfare-state capitalism than by property-owning democracy.
Temporal changes of symbiont density and host fitness after rifampicin treatment in a whitefly of the Bemisia tabaci species complex
Authors: Shan Hong‐Wei , Zhang Chang‐Rong , Yan Ting‐Ting , Tang Hai‐Qin , Wang Xiao‐Wei , Liu Shu‐Sheng , Liu Yin‐Quan
Published: September 2015

Microbial symbionts are essential or important partners to phloem‐feeding insects. Antibiotics have been used to selectively eliminate symbionts from their host insects and establish host lines with or without certain symbionts for investigating functions of the symbionts. In this study, using the antibiotic rifampicin we attempted to selectively eliminate certain symbionts from a population of the Middle East‐Asia Minor 1 whitefly of the Bemisia tabaci species complex, which harbors the primary symbiont “Candidatus Portiera aleyrodidarum” and two secondary symbionts “Candidatus Hamiltonella defensa” and Rickettsia. Neither the primary nor the secondary symbionts were completely depleted in the adults (F0) that fed for 48 h on a diet treated with rifampicin at concentrations of 1–100 μg/mL. However, both the primary and secondary symbionts were nearly completely depleted in the offspring (F1) of the rifampicin‐treated adults. Although the F1 adults produced some eggs (F2), most of the eggs failed to hatch and none of them reached the second instar, and consequently the rifampicin‐treated whitefly colony vanished at the F2 generation. Interestingly, quantitative polymerase chain reaction assays showed that in the rifampicin‐treated whiteflies, the density of the primary symbiont was reduced at an obviously slower pace than the secondary symbionts. Mating experiments between rifampicin‐treated and untreated adults demonstrated that the negative effects of rifampicin on host fitness were expressed when the females were treated by the antibiotic, and whether males were treated or not by the antibiotic had little contribution to the negative effects. These observations indicate that with this whitefly population it is not feasible to selectively eliminate the secondary symbionts using rifampicin without affecting the primary symbiont and establish host lines for experimental studies. However, the extinction of the whitefly colony at the second generation after rifampicin treatment indicates the potential of the antibiotic as a control agent of the whitefly pest.
Feasibility of an Area‐Yield Insurance Scheme in the EU: Evidence from Finland
Authors: Liesivaara Petri , Myyrä Sami
Published: September 2015

Yield variability increases farm income volatility. This volatility is expected to increase as the frequency of extreme weather events intensifies with climate change. Preparation is needed in farm practices, but also in economic risk management on farms. In the EU, new crop insurance schemes are to be founded on public–private partnerships. Member States and the EU will subsidise farmers purchasing crop insurance from private insurance companies or mutual funds. At the same time, the EU is signalling that basis risk, i.e. potential mismatch between insurance pay‐out and actual crop losses at the farm level will not be tolerated. We conducted a feasibility study of area‐yield index insurance in Finland using farm‐level data. Yields between areas likely to be used in insurance policies and individual farm yields are weakly correlated. By determining the optimal cover and scale of area‐yield insurance for farms, we show that flexibility is needed in the rules for subsidised crop insurance. Systemic risks from area‐yield insurance are considerable. Because there is high correlation between area yields, insurance companies may suffer large scale losses in a given year. We suggest co‐operation in the provision of crop insurance at the EU level to enable more effective risk pooling.
Fruit Phenolic Composition of Different Elderberry Species and Hybrids
Authors: Mikulic‐Petkovsek Maja , Ivancic Anton , Todorovic Biljana , Veberic Robert , Stampar Franci
Published: September 2015

The aim of this study was to investigate a detailed composition and content of phenolic compounds in fruits of 4 elderberry species (Sambucus nigra, S. cerulea, S. ebulus, and S racemosa) and 8 interspecific hybrids. Hydroxycinnamic acids (HCAs) represented the major share of phenolics in analyzed elderberries; caffeoylquinic and p‐coumaroylquinic acids were most abundant. Flavanols (catechin, epicatechin, and different procyanidins) were the second major phenolic group detected in range from 2% to 30% of total analyzed phenolics. From the group of flavonols, 13 different quercetin glycosides, 7 kaempferol glycosides, and 8 isorhamnetin glycosides have been quantified. Rutin was the major flavonol in all studied genotypes. S. ebulus was characterized by the highest level of total HCAs, catechin, epicatechin, and most flavonols. Some elderberry hybrids, for example JA × RAC, CER × NI, and JA × (JA × NI), are perspective for further studies because they have high content of phenolic compounds. The results of research could contribute to breed cultivars, which may prove interesting for food‐processing industries.
Profiles of Phenolic Acids and Flavan‐3‐ols for Select Chinese Red Wines: A Comparison and Differentiation According to Geographic Origin and Grape Variety
Authors: Sun Xiangyu , Li Le , Ma Tingting , Liu Xingyan , Huang Weidong , Zhan Jicheng
Published: September 2015

The profiles of phenolic acids and flavan‐3‐ols for the selected Chinese red wines and the potential of using phenolic acids and flavan‐3‐ols to differentiate the geographic origin and grape variety of wines from China are investigated in this study. Significant differences and markers could be found according to the geographical origin and grape variety. Through a canonical discriminant analysis a good differentiation was developed according to the geographic origin or grape variety, and the accuracy of the discriminant model was 88.9% and 100%, respectively. According to the phenolic acid and flavan‐3‐ols profiles of the wine samples and good differentiation in the region and the variety discriminant analysis, minimal fraudulent claims were noted for the Chinese red wines investigated.