bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural, dynamic, electronic, and vibrational properties of flexible, intermediate, and stressed rigid As-Se glasses and liquids from first principles molecular dynamics
Authors: Bauchy M. , Kachmar A. , Micoulaut M.
Published: November 2014

The structural, vibrational, electronic, and dynamic properties of amorphous and liquid AsxSe1-x (0.10 <x < 0.45) are studied by First Principles Molecular Dynamics. Within the above range of compositions, thresholds, and anomalies are found in the behavior of reciprocal and real space properties that can be correlated to the experimental location of the Boolchand intermediate phase in these glassy networks, observed at 0.27 <x < 0.37. These findings are associated with diffusion anomalies for the parent liquid phase, thereby linking structural and dynamical atomic-scale fingerprints for the onset of rigidity within the network, while also providing a much more complex picture than the one derived from mean-field approaches of stiffness transitions.
Economic and cradle-to-gate life cycle assessment of poly-3-hydroxybutyrate production from plastic producing, genetically modified hybrid poplar leaves
Authors: Hohenschuh William , Kumar Deepak , Murthy Ganti S.
Published: November 2014

Poly-3-hydroxybutyrate (PHB) is a renewable, biodegradable biopolymer that has shown great promise to offset the use of hydrocarbon-derived plastics. The genes encoding the bacterial PHB production pathway have been engineered into several higher order plant species providing an opportunity to produce PHB as a co-product on an industrial, agricultural scale. This study investigates the economic feasibility and estimates the life-cycle greenhouse gas (GHG) emissions produced during the PHB production from hybrid poplar leaves. An established, bench scale extraction procedure was extrapolated upon using SuperPro designer to estimate the product cost, raw materials and energy used during extraction of PHB from poplar leaves on an industrial scale. Assuming an economically feasible concentration of PHB could be produced in the leaf material, a cradle-to-gate life cycle assessment was performed under two of the most likely poplar production scenarios for the Northwest United States where poplar is commonly grown for biomass applications. The cost of PHB production was found to vary greatly with the PHB content in the leaves; from $33.28 per kg at 0.5% PHB to $1.72 per kg at 20% PHB content. Poplar production scenarios varied greatly in their emission of GHGs. An irrigated poplar production scenario is estimated to produce 248.8% more GHGs than production of the displaced polypropylene. An un-irrigated poplar production scenario produced 76.1% less GHGs. Both production scenarios produced significant amounts of volatile organic compounds (VOCs) associated with normal poplar growth that could prove detrimental to local air quality. PHB content of 15% in the poplar was required to bring the PHB production price to $2.26 per kg and make production competitive with petroleum-derived plastics.
High-sensitivity cooled coil system for nuclear magnetic resonance in kHz range
Authors: Lin Tingting , Zhang Yi , Lee Yong-Ho , Krause Hans-Joachim , Lin Jun , Zhao Jing
Published: November 2014

In several low-field Nuclear Magnetic Resonance (LF-NMR) and surface nuclear magnetic resonance applications, i.e., in the frequency range of kHz, high sensitivity magnetic field detectors are needed. Usually, low-Tc superconducting quantum interference devices (SQUIDs) with a high field sensitivity of about 1 fT/Hz1/2 are employed as detectors. Considering the flux trapping and operational difficulties associated with low-Tc SQUIDs, we designed and fabricated liquid-nitrogen-cooled Cu coils for NMR detection in the kHz range. A cooled coil system consisting of a 9-cm diameter Cu coil and a low noise preamplifier was systematically investigated and reached a sensitivity of 2 fT/Hz1/2 at 77 K, which is 3 times better compared to the sensitivity at 300 K. A Q-switch circuit as an essential element for damping the ringing effects of the pickup coil was developed to acquire free induction decay signals of a water sample with minimum loss of signal. Our studies demonstrate that cooled Cu coils, if designed properly, can provide a comparable sensitivity to low-Tc SQUIDs.
Quantitative transmission electron microscopy analysis of multi-variant grains in present L1-FePt based heat assisted magnetic recording media
Authors: Ho Hoan , Zhu Jingxi , Kulovits Andreas , Laughlin David E. , Zhu Jian-Gang
Published: November 2014

We present a study on atomic ordering within individual grains in granular L10-FePt thin films using transmission electron microscopy techniques. The film, used as a medium for heat assisted magnetic recording, consists of a single layer of FePt grains separated by non-magnetic grain boundaries and is grown on an MgO underlayer. Using convergent-beam techniques, diffraction patterns of individual grains are obtained for a large number of crystallites. The study found that although the majority of grains are ordered in the perpendicular direction, more than 15% of them are multi-variant, or of in-plane c-axis orientation, or disordered fcc. It was also found that these multi-variant and in-plane grains have always grown across MgO grain boundaries separating two or more MgO grains of the underlayer. The in-plane ordered portion within a multi-variant L10-FePt grain always lacks atomic coherence with the MgO directly underneath it, whereas, the perpendicularly ordered portion is always coherent with the underlying MgO grain. Since the existence of multi-variant and in-plane ordered grains are severely detrimental to high density data storage capability, the understanding of their formation mechanism obtained here should make a significant impact on the future development of hard disk drive technology.
Nonquasineutral electron vortices in nonuniform plasmas
Authors: Angus J. R. , Richardson A. S. , Ottinger P. F. , Swanekamp S. B. , Schumer J. W.
Published: November 2014

Electron vortices are observed in the numerical simulation of current carrying plasmas on fast time scales where the ion motion can be ignored. In plasmas with nonuniform density n, vortices drift in the B × ∇n direction with a speed that is on the order of the Hall speed. This provides a mechanism for magnetic field penetration into a plasma. Here, we consider strong vortices with rotation speeds Vϕ close to the speed of light c where the vortex size δ is on the order of the magnetic Debye length λB=|B|/4πen and the vortex is thus nonquasineutral. Drifting vortices are typically studied using the electron magnetohydrodynamic model (EMHD), which ignores the displacement current and assumes quasineutrality. However, these assumptions are not strictly valid for drifting vortices when δ ≈ λB. In this paper, 2D electron vortices in nonuniform plasmas are studied for the first time using a fully electromagnetic, collisionless fluid code. Relatively large amplitude oscillations with periods that correspond to high frequency extraordinary modes are observed in the average drift speed. The drift speed W is calculated by averaging the electron velocity field over the vorticity. Interestingly, the time-averaged W from these simulations matches very well with W from the much simpler EMHD simulations even for strong vortices with order unity charge density separation.
Complete electroelastic set for the (YXt)-45° cut of a KNbO3 single crystal
Authors: Rouffaud R. , Marchet P. , Hladky-Hennion A.-C. , Bantignies C. , Pham-Thi M. , Levassort F.
Published: November 2014

A complete and consistent set (elastic, dielectric, and piezoelectric tensors) of a commercial lead-free (YXt)-45° cut KNbO3 single crystal is reported. These data were obtained using several samples and the resonance-antiresonance method. Particular attention was paid to the consistency of this delivered database. A genetic algorithm with an appropriate criterion was used. Electromechanical characterization revealed a high thickness coupling factor of approximately 60%. These properties make this single crystal a good candidate for several applications such as medical imaging. This complete set provides a basis for simulation designs of such devices integrating this piezoelectric lead-free material, especially for ultrasonic transducers.
Fluorescence resonance energy transfer measured by spatial photon migration in CdSe-ZnS quantum dots colloidal systems as a function of concentration
Authors: Azevedo G. , Monte A. F. G. , Reis A. F. , Messias D. N.
Published: November 2014

The study of the spatial photon migration as a function of the concentration brings into attention the problem of the energy transfer in quantum dot embedded systems. By measuring the photon propagation and its spatial dependence, it is possible to understand the whole dynamics in a quantum dot system, and also improve their concentration dependence to maximize energy propagation due to radiative and non-radiative processes. In this work, a confocal microscope was adapted to scan the spatial distribution of photoluminescence from CdSe-ZnS core-shell quantum dots in colloidal solutions. The energy migration between the quantum dots was monitored by the direct measurement of the photon diffusion length, according to the diffusion theory. We observed that the photon migration length decreases by increasing the quantum dot concentration, this kind of behavior has been regarded as a signature of Förster resonance energy transfer in the system.
Broadly tunable, high-power terahertz radiation up to 73 K from a stand-alone Bi2Sr2CaCu2O8+δ mesa
Authors: Kitamura T. , Kashiwagi T. , Yamamoto T. , Tsujimoto M. , Watanabe C. , Ishida K. , Sekimoto S. , Asanuma K. , Yasui T. , Nakade K. , Shibano Y. , Saiwai Y. , Minami H. , Klemm R. A. , Kadowaki K.
Published: November 2014

High-power, continuous, broadly tunable THz radiation from 0.29 to 1.06 THz, was obtained from the outer current-voltage characteristic (IVC) branch of a single stand-alone mesa of the high-transition temperature Tc superconductor Bi2Sr2CaCu2O8+δ. The particular metallic film structures placed both beneath and atop the mesas resulted in more efficient heat dissipation, higher allowed applied dc voltages, larger IVC loops, wider emission temperature ranges, and much broader emission frequency tunability than obtained previously.
n+-GaN grown by ammonia molecular beam epitaxy: Application to regrown contacts
Authors: Lugani L. , Malinverni M. , Tirelli S. , Marti D. , Giraud E. , Carlin J.-F. , Bolognesi C. R. , Grandjean N.
Published: November 2014

We report on the low-temperature growth of heavily Si-doped (>1020 cm−3) n+-type GaN by N-rich ammonia molecular beam epitaxy (MBE) with very low bulk resistivity (<4 × 10−4 Ω·cm). This is applied to the realization of regrown ohmic contacts on InAlN/GaN high electron mobility transistors. A low n+-GaN/2 dimensional electron gas contact resistivity of 0.11 Ω·mm is measured, provided an optimized surface preparation procedure, which is shown to be critical. This proves the great potentials of ammonia MBE for the realization of high performance electronic devices.
Increasing label-free stem cell sorting capacity to reach transplantation-scale throughput
Authors: Simon Melinda G. , Li Ying , Arulmoli Janahan , McDonnell Lisa P. , Akil Adnan , Nourse Jamison L. , Lee Abraham P. , Flanagan Lisa A.
Published: November 2014

Dielectrophoresis (DEP) has proven an invaluable tool for the enrichment of populations of stem and progenitor cells owing to its ability to sort cells in a label-free manner and its biological safety. However, DEP separation devices have suffered from a low throughput preventing researchers from undertaking studies requiring large numbers of cells, such as needed for cell transplantation. We developed a microfluidic device designed for the enrichment of stem and progenitor cell populations that sorts cells at a rate of 150,000 cells/h, corresponding to an improvement in the throughput achieved with our previous device designs by over an order of magnitude. This advancement, coupled with data showing the DEP-sorted cells retain their enrichment and differentiation capacity when expanded in culture for periods of up to 2 weeks, provides sufficient throughput and cell numbers to enable a wider variety of experiments with enriched stem and progenitor cell populations. Furthermore, the sorting devices presented here provide ease of setup and operation, a simple fabrication process, and a low associated cost to use that makes them more amenable for use in common biological research laboratories. To our knowledge, this work represents the first to enrich stem cells and expand them in culture to generate transplantation-scale numbers of differentiation-competent cells using DEP.
Phase transition and strength of vanadium under shock compression up to 88 GPa
Authors: Yu Yuying , Tan Ye , Dai Chengda , Li Xuemei , Li Yinghua , Wu Qiang , Tan Hua
Published: November 2014

A series of reverse-impact experiments were performed on vanadium at shock pressure ranging from 32 GPa to 88 GPa. Particle velocity profiles measured at sample/LiF window interface were used to estimate the sound velocities, shear modulus, and yield stress in shocked vanadium. A phase transition at ∼60.5 GPa that may be the body-centered cubic (BCC) to rhombohedral structure was identified by the discontinuity of the sound velocity against shock pressure. This transition pressure is consistent with the results from diamond anvil cell (DAC) experiments and first-principle calculations. However, present results show that the rhombohedral phase has higher strength and shear modulus than the BCC phase, which is contrast to the findings from DAC experiments and theoretical work.
Compositional tuning of atomic layer deposited MgZnO for thin film transistors
Authors: Wrench J. S. , Brunell I. F. , Chalker P. R. , Jin J. D. , Shaw A. , Mitrovic I. Z. , Hall S.
Published: November 2014

Thin film transistors (TFTs) have been fabricated using magnesium zinc oxide (MgZnO) layers deposited by atomic layer deposition at 200 °C. The composition of the MgZnO is systematically modified by varying the ratio of MgO and ZnO deposition cycles. A blue-shift of the near band-edge photoluminescence after post-deposition annealing at 300 °C indicates significant activation of the Mg dopant. A 7:1 ratio of ZnO:MgO deposition cycles was used to fabricate a device with a TFT channel width of 2000 μm and a channel length of 60 μm. This transistor yielded an effective saturation mobility of 4 cm2/V s and a threshold voltage of 7.1 V, respectively. The on/off ratio was 1.6×106 and the maximum interface state density at the ZnO/SiO2 interface is ∼6.5×1012 cm−2.
Metallic stereostructured layer: An approach for broadband polarization state manipulation
Authors: Xiong Xiang , Hu Yuan-Sheng , Jiang Shang-Chi , Hu Yu-Hui , Fan Ren-Hao , Ma Guo-Bin , Shu Da-Jun , Peng Ru-Wen , Wang Mu
Published: November 2014

In this letter, we report a full-metallic broadband wave plate assembled by standing metallic L-shaped stereostructures (LSSs). We show that with an array of LSSs, high polarization conversion ratio is achieved within a broad frequency band. Moreover, by rotating the orientation of the array of LSSs, the electric components of the reflection beam in two orthogonal directions and their phase difference can be independently tuned. In this way, all the polarization states on the Poincaré sphere can be realized. As examples, the functionalities of a quarter wave plate and a half wave plate are experimentally demonstrated with both reflection spectra and focal-plane-array imaging. Our designing provides a unique approach in realizing the broadband wave plate to manipulate the polarization state of light.
Exploring the mental lexicon
Authors: Acha Joana , Carreiras Manuel
Published: November 2014

Visual word recognition is a capital stage in reading. It involves accessing a mental representation of a written word, including processes such as perception, letter coding and selection of the proper candidate in our mental lexicon. One key issue for researchers on this field is to shed light on the role of phonological and orthographic processes in lexical access, as well as the choice of an input coding scheme for orthographic representations. In this paper we will review the state of the art about sublexical and lexical processes involved in lexical access. We will discuss behavioral, eye movement and electrophysiological evidence to understand: (i) which are the most important coding units, (ii) how our visual system codes identity and position of such units, (iii) which factors modulate the way we access lexical information in our minds, and (iv) the time course of such processes. We will do so from a methodological perspective, exploring a broad range of paradigms and effects that provide a complete framework about how printed words are coded and represented in our minds.
Rapid phylogenetic analysis of large samples of recombinant bacterial whole genome sequences using Gubbins
Authors: Croucher Nicholas J. , Page Andrew J. , Connor Thomas R. , Delaney Aidan J. , Keane Jacqueline A. , Bentley Stephen D. , Parkhill Julian , Harris Simon R.
Published: November 2014

The emergence of new sequencing technologies has facilitated the use of bacterial whole genome alignments for evolutionary studies and outbreak analyses. These datasets, of increasing size, often include examples of multiple different mechanisms of horizontal sequence transfer resulting in substantial alterations to prokaryotic chromosomes. The impact of these processes demands rapid and flexible approaches able to account for recombination when reconstructing isolates’ recent diversification. Gubbins is an iterative algorithm that uses spatial scanning statistics to identify loci containing elevated densities of base substitutions suggestive of horizontal sequence transfer while concurrently constructing a maximum likelihood phylogeny based on the putative point mutations outside these regions of high sequence diversity. Simulations demonstrate the algorithm generates highly accurate reconstructions under realistically parameterized models of bacterial evolution, and achieves convergence in only a few hours on alignments of hundreds of bacterial genome sequences. Gubbins is appropriate for reconstructing the recent evolutionary history of a variety of haploid genotype alignments, as it makes no assumptions about the underlying mechanism of recombination. The software is freely available for download at github.com/sanger-pathogens/Gubbins, implemented in Python and C and supported on Linux and Mac OS X.
Adaptation to larval crowding inDrosophila ananassaeandDrosophila nasuta nasuta: increased larval competitive ability without increased larval feeding rate
Authors: Nagarajan Archana , Natarajan Sharmila Bharathi , Jayaram Mohan , Thammanna Ananda , Chari Sudarshan , Bose Joy , Jois Shreyas V. , Joshi Amitabh
Published: November 2014

The standard view of adaptation to larval crowding in fruitflies, built on results from 25 years of multiple experimental evolution studies onD. melanogaster, is that enhanced competitive ability evolves primarily through increased larval feeding and foraging rate, at the cost of efficiency of food conversion to biomass, and increased larval tolerance to nitrogenous wastes. These results, moreover, were at odds from the predictions of classicalK-selection theory, notably the expectation that selection at high density should result in the increase of efficiency of conversion of food to biomass, and were better interpreted through the lens ofα-selection. We show here that populations ofD. ananassaeandD. n. nasutasubjected to extreme larval crowding evolve greater competitive ability and pre-adult survivorship at high density primarily through a combination of reduced larval duration, faster attainment of minimum critical size for pupation, greater time efficiency of food conversion to biomass, increased pupation height with a relatively small role of increased urea/ammonia tolerance, if at all. This is a very different suite of traits than that seen to evolve under similar selection inD.melanogasterand seems to be closer to the expectations from the canonical theory ofK-selection. We discuss possible reasons for these differences in results across the three species. Overall, the results reinforce the view that our understanding of the evolution of competitive ability in fruitflies needs to be more nuanced than before, with an appreciation that there may be multiple evolutionary routes through which higher competitive ability can be attained.
High-resolution structures of cholesterol oxidase in the reduced state provide insights into redox stabilization
Authors: Golden Emily , Karton Amir , Vrielink Alice
Published: November 2014

Cholesterol oxidase (CO) is a flavoenzyme that catalyzes the oxidation and isomerization of cholesterol to cholest-4-en-3-one. The reductive half reaction occursviaa hydride transfer from the substrate to the FAD cofactor. The structures of CO reduced with dithionite under aerobic conditions and in the presence of the substrate 2-propanol under both aerobic and anaerobic conditions are presented. The 1.32 Å resolution structure of the dithionite-reduced enzyme reveals a sulfite molecule covalently bound to the FAD cofactor. The isoalloxazine ring system displays a bent structure relative to that of the oxidized enzyme, and alternate conformations of a triad of aromatic residues near to the cofactor are evident. A 1.12 Å resolution anaerobically trapped reduced enzyme structure in the presence of 2-propanol does not show a similar bending of the flavin ring system, but does show alternate conformations of the aromatic triad. Additionally, a significant difference electron-density peak is observed within a covalent-bond distance of N5 of the flavin moiety, suggesting that a hydride-transfer event has occurred as a result of substrate oxidation trapping the flavin in the electron-rich reduced state. The hydride transfer generates a tetrahedral geometry about the flavin N5 atom. High-level density-functional theory calculations were performed to correlate the crystallographic findings with the energetics of this unusual arrangement of the flavin moiety. These calculations suggest that strong hydrogen-bond interactions between Gly120 and the flavin N5 centre may play an important role in these structural features.
Structures ofPlasmodium vivaxserine hydroxymethyltransferase: implications for ligand-binding specificity and functional control
Authors: Chitnumsub Penchit , Jaruwat Aritsara , Riangrungroj Pinpunya , Ittarat Wanwipa , Noytanom Krittikar , Oonanant Worrapoj , Vanichthanankul Jarunee , Chuankhayan Phimonphan , Maenpuen Somchart , Chen Chun-Jung , Chaiyen Pimchai , Yuthavong Yongyuth , Leartsakulpanich Ubolsree
Published: November 2014

Plasmodiumparasites, the causative agent of malaria, rely heavily onde novofolate biosynthesis, and the enzymes in this pathway have therefore been explored extensively for antimalarial development. Serine hydroxymethyltransferase (SHMT) fromPlasmodiumspp., an enzyme involved in folate recycling and dTMP synthesis, has been shown to catalyze the conversion of L- and D-serine to glycine (Gly) in a THF-dependent reaction, the mechanism of which is not yet fully understood. Here, the crystal structures ofP. vivaxSHMT (PvSHMT) in a binary complex with L-serine and in a ternary complex with D-serine (D-Ser) and (6R)-5-formyltetrahydrofolate (5FTHF) provide clues to the mechanism underlying the control of enzyme activity. 5FTHF in the ternary-complex structure was found in the 6Rform, thus differing from the previously reported structures of SHMT–Gly–(6S)-5FTHF from other organisms. This suggested that the presence of D-Ser in the active site can alter the folate-binding specificity. Investigation of binding in the presence of D-Ser and the (6R)- or (6S)-5FTHF enantiomers indicated that both forms of 5FTHF can bind to the enzyme but that only (6S)-5FTHF gives rise to a quinonoid intermediate. Likewise, a large surface area with a highly positively charged electrostatic potential surrounding thePvSHMT folate pocket suggested a preference for a polyglutamated folate substrate similar to the mammalian SHMTs. Furthermore, as inP. falciparumSHMT, a redox switch created from a cysteine pair (Cys125–Cys364) was observed. Overall, these results assert the importance of features such as stereoselectivity and redox status for control of the activity and specificity ofPvSHMT.
Structural and functional insights into an archaealL-asparaginase obtained through the linker-less assembly of constituent domains
Authors: Tomar Rachana , Sharma Pankaj , Srivastava Ankit , Bansal Saurabh , Ashish  , Kundu Bishwajit
Published: November 2014

Covalent linkers bridging the domains of multidomain proteins are considered to be crucial for assembly and function. In this report, an exception in which the linker of a two-domain dimeric L-asparaginase fromPyrococcus furiosus(PfA) was found to be dispensable is presented. Domains of this enzyme assembled without the linker into a conjoined tetrameric form that exhibited higher activity than the parent enzyme. The global shape and quaternary structure of the conjoined PfA were also similar to the wild-type PfA, as observed by their solution scattering profiles and X-ray crystallographic data. Comparison of the crystal structures of substrate-bound and unbound enzymes revealed an altogether new active-site composition and mechanism of action. Thus, conjoined PfA is presented as a unique enzyme obtained through noncovalent, linker-less assembly of constituent domains that is stable enough to function efficiently at elevated temperatures.
Crystal structure of 3-[({2-[bis(2-hydroxybenzyl)amino]ethyl}(2-hydroxybenzyl)amino)methyl]-2-hydroxy-5-methylbenzaldehyde
Authors: Fonseca Alexandra S. , Bortoluzzi Adailton J.
Published: November 2014

The non-symmetric title molecule, C32H34N2O5, is based on a tetrasubstituted ethylenediamine backbone. The molecular structure consists of three hydroxybenzyl groups and one 2-hydroxy-5-methylbenzaldehyde group bonded to the N atoms of the diamine unit. The ethylenediamine skeleton shows a regular extended conformation, while the spatial orientation of the phenol arms is governed by hydrogen bonds. In the 2-hydroxy-5-methylbenzaldehyde group, an intramolecularS(6) O—H...O hydrogen bond is observed between the alcohol and aldehyde functions, and the neighbouring phenol arm participates in an intramolecularS(6) O—H...N hydrogen bond. The third phenol group is involved in a bifurcated intramolecular hydrogen bond with graph-set notationS(6) for O—H...N and O—H...O intramolecular hydrogen bonds between neighbouring amine and phenol arms, respectively. Finally, the fourth phenol group acts as an acceptor in a bifurcated intramolecular hydrogen bond and also acts as donor in an intermolecular hydrogen bond, which connects inversion-related molecules into dimers withR44(8) ring motifs.
Crystal structure of a second polymorph of tetrakis(pyridin-2-yl)methane
Authors: Matsumoto Kouzou , Kannami Masaki , Fuyuhiro Akira , Oda Masaji
Published: November 2014

A second polymorph of the title compound, C21H16N4, is reported. The original polymorph was solved by our group [Matsumotoet al.(2003).Tetrahedron Lett.44, 2861–2864] in the monoclinic space groupC2/cand refined toR= 0.050. Now the crystal structure of a tetragonal polymorph (space groupP-421c) has been solved and refined toR= 0.036. In the crystal, there are no strong intermolecular interactions. Reflecting the high symmetry of the molecular structure, the asymmetric unit is a quarter of the molecule, and the molecule exhibitsS4 symmetry along thecaxis in the crystal.
Crystal structure of piperidinium 4-nitrophenolate
Authors: Sowmya N. Swarna , Sampathkrishnan S. , Sudhahar S. , Chakkaravarthi G. , Kumar R. Mohan
Published: November 2014

In the title molecular salt, C5H12N+·C6H4NO3−, the piperidine ring adopts a chair conformation and the cation is protonated at the N atom. In the anion, the nitro group is twisted at an angle of 10.30 (11)° with respect to the attached benzene ring. In the crystal, N—H...O hydrogen bonds link adjacent anions and cations into infinite chains propagating along [100]. The chains are linked by C—H...π interactions, forming sheets lying parallel to (001).
Personality traits and party identification over time
Authors: Bakker Bert N. , Hopmann David Nicolas , Persson Mikael
Published: November 2014

Why do some people stably identify with a party while others do not? This study tests whether and how the direction, stability and strength of party identification are associated with big five personality traits, using panel data from a representative sample of German citizens. First, the study confirms that personality traits are related to identification with different political parties. Second, it moves beyond previous research by showing that personality traits are related to the strength and variation in party identification over time. The implications of the study for the classical perspectives on party identification, as well as the personality and politics literature, are discussed.
Hyperandrogenism and phenotypes of polycystic ovary syndrome are not associated with differences in obstetric outcomes
Authors: Mumm Hanne , Jensen Dorte Møller , Sørensen Jens Aage , Andersen Lise Lotte Torvin , Ravn Pernille , Andersen Marianne , Glintborg Dorte
Published: November 2014

Objectives

To investigate obstetric outcomes in Danish women with different phenotypes of polycystic ovary syndrome (PCOS) and isolated hyperandrogenism (HA) and describe the risk of adverse obstetric outcomes in women with PCOS and HA compared to controls.

Design

Cohort study.

Setting

Odense University Hospital, Denmark.

Population

Women with PCOS were identified prospectively starting in 1997. Singleton pregnancies in women with PCOS and HA during 2003–2011 were included (n = 199). A control group was matched to the patient cohort according to date of childbirth (n = 995).

Methods

Data on clinical characteristics and obstetric outcomes were collected in patients with PCOS and HA and controls. In PCOS and HA, total and free testosterone, sex hormone binding globulin, and hemoglobin A1c were measured outside pregnancy. During pregnancy, oral glucose tolerance tests were performed in 39 patients and 123 controls according to Danish national guidelines. PCOS phenotypes were based on the Rotterdam criteria.

Main outcome measures

Gestational diabetes mellitus, pregnancy‐induced hypertension, preeclampsia, delivery by emergency cesarean section, preterm delivery and anthropometric measures in the newborn.

Results

The incidence of adverse obstetric outcomes and anthropometric measures among the newborns were comparable between different phenotypes of PCOS and patients with HA. In the oral glucose tolerance test, patients had a higher risk of gestational diabetes mellitus compared with controls; the odds ratio (95% confidence interval) was 3.3 (1.5–6.9) after adjustment for age, parity, and body mass index (p = 0.002). The incidence of other adverse obstetric outcomes was similar in patients and controls.

Conclusions

Obstetric outcomes were comparable in women with different PCOS phenotypes.
Tofacitinib withdrawal and retreatment in moderate-to-severe chronic plaque psoriasis: a randomized controlled trial
Authors: Bissonnette R. , Iversen L. , Sofen H. , Griffiths C.E.M. , Foley P. , Romiti R. , Bachinsky M. , Rottinghaus S.T. , Tan H. , Proulx J. , Valdez H. , Gupta P. , Mallbris L. , Wolk R.
Published: November 2014

Background

Tofacitinib is an oral Janus kinase inhibitor being investigated for the treatment of moderate-to-severe plaque psoriasis.

Objectives

To compare outcomes following tofacitinib withdrawal with outcomes of continuation.

Methods

In this phase 3 study (NCT01186744), patients received tofacitinib 5 mg (n =331) or 10 mg (n =335) twice daily for 24 weeks. The patients who achieved both ≥ 75% reduction in Psoriasis Area and Severity Index (PASI 75) score from baseline and Physician's Global Assessment (PGA) of ‘clear’ or ‘almost clear’ (PGA response) received a placebo (withdrawal) or the previous dose. At relapse (> 50% reduction in the PASI improvement during initial treatment) or week 40, the patients received the initial dose.

Results

Initial treatment: 33·5% and 55·2% achieved both PASI 75 and PGA responses with tofacitinib 5 and 10 mg twice daily, respectively, making them eligible for the treatment-withdrawal period. Withdrawal: 56·2%, 62·3%, 23·3% and 26·1% maintained PASI 75 responses with tofacitinib 5, 10 mg, placebo (5 mg) and placebo (10 mg) twice daily, respectively; 49·9%, 63·9%, 22·9% and 18·0% maintained PGA responses; and 92·3%, 93·0%, 32·8% and 42·9% did not relapse. Elevations in low-density lipoprotein–cholesterol levels following initial treatment (mean increase: 8·71 mg dL−1 with 5 mg twice daily, 10·26 mg dL−1 with 10 mg twice daily) were reversed upon withdrawal. Retreatment: 36·8% and 61·0% of patients who relapsed achieved PASI 75 responses with tofacitinib 5 or 10 mg after 16 weeks; 44·8% and 57·1% regained PGA responses.

Conclusions

Patients who received continuous treatment maintained a response more effectively when compared with placebo recipients. Safety profiles were comparable in both the continuous treatment group and retreatment group. Of those patients who relapsed, up to 60% recaptured a response with tofacitinib.
Colour fluctuations in grapheme‐colour synaesthesia: The effect of clinical and non‐clinical mood changes
Authors: Kay Collette L. , Carmichael Duncan A. , Ruffell Henry E. , Simner Julia
Published: November 2014

Synaesthesia is a condition that gives rise to unusual secondary sensations (e.g., colours are perceived when listening to music). These unusual sensations tend to be reported as being stable throughout adulthood (e.g., Simner & Logie, 2007, Neurocase, 13, 358) and the consistency of these experiences over time is taken as the behavioural hallmark of genuineness. Our study looked at the influence of mood states on synaesthetic colours. In Experiment 1, we recruited grapheme‐colour synaesthetes (who experience colours from letters/digits) and elicited their synaesthetic colours, as well as their mood and depression states, in two different testing sessions. In each session, participants completed the PANAS‐X (Watson & Clark, 1999) and the BDI‐II (Beck, Steer, & Brown, 1996, Manual for Beck Depression Inventory‐II), and chose their synaesthetic colours for letters A‐Z from an interactive colour palette. We found that negative mood significantly decreased the luminance of synaesthetic colours. In Experiment 2, we showed that synaesthetic colours were also less luminant for synaesthetes with anxiety disorder, versus those without. Additional evidence suggests that colour saturation, too, may inversely correlate with depressive symptoms. These results show that fluctuations in mood within both a normal and clinical range influence synaesthetic colours over time. This has implications for our understanding about the longitudinal stability of synaesthetic experiences, and of how mood may interact with the visual (imagery) systems.
Methylation‐induced downregulation of TFPI‐2 causes TMPRSS4 overexpression and contributes to oncogenesis in a subset of non‐small‐cell lung carcinoma
Authors: Hamamoto Junko , Soejima Kenzo , Naoki Katsuhiko , Yasuda Hiroyuki , Hayashi Yuichiro , Yoda Satoshi , Nakayama Sohei , Satomi Ryosuke , Terai Hideki , Ikemura Shinnosuke , Sato Takashi , Arai Daisuke , Ishioka Kota , Ohgino Keiko , Betsuyaku Tomoko
Published: November 2014

We identified transmembrane protease, serine 4 (TMPRSS4) as a putative, druggable target by screening surgically resected samples from 90 Japanese non‐small‐cell lung cancer (NSCLC) patients using cDNA microarray. TMPRSS4 has two druggable domains and was upregulated in 94.5% of the lung cancer specimens. Interestingly, we found that TMPRSS4 expression was associated with tissue factor pathway inhibitor 2 (TFPI‐2) expression in these clinical samples. In contrast to TMPRSS4, TFPI‐2 expression was downregulated in NSCLC samples. The in vitro induction of TFPI‐2 in lung cancer cell lines decreased the expression of TMPRSS4 mRNA levels. Reporter assay showed that TFPI‐2 inhibited transcription of TMPRSS4, although partially. Knockdown of TMPRSS4 reduced the proliferation rate in several lung cancer cell lines. When lung cancer cell lines were treated with 5‐aza‐2′‐deoxycytidine or trichostatin A, their proliferation rate and TMPRSS4 mRNA expression levels were also reduced through the upregulation of TFPI‐2 by decreasing its methylation in vitro. The TFPI‐2 methylation level in the low TMPRSS4 group appeared to be significantly low in NSCLC samples (P = 0.02). We found a novel molecular mechanism that TFPI‐2 negatively regulates cell growth by inhibiting transcription of TMPRSS4. We suggest that TMPRSS4 is upregulated by silencing of TFPI‐2 through aberrant DNA methylation and contributes to oncogenesis in NSCLC.
Women on Corporate Boards in Italy: The Role of Family Connections
Authors: Bianco Magda , Ciavarella Angela , Signoretti Rossella
Published: November 2014

Manuscript Type

Empirical

Research Question/Issue

This paper sets out to shed light on female representation on Italian corporate boards before the introduction of gender quota legislation in 2012, as well as on the relevance of family connections. We investigate the potential determinants of having boards with diverse representation and the correlation between female directorship and family connections, with a focus on governance measures.

Research Findings

Using data on all directors of Italian publicly traded companies from 2008 to 2010, we identify two different models. In the majority of gender‐diverse boards, at least one woman has a family connection to the controlling shareholder. Family‐affiliated women are more common in companies that are small, have a concentrated ownership, are in the consumer sector, and have a larger board. Conversely, non‐family‐affiliated women are more common on the boards of companies that are widely held, have younger and more educated boards, have a higher proportion of independent directors, and have a smaller number of interlocked directors. With reference to governance‐related outcomes, the number of board meetings appears to be negatively correlated to both the presence of family members and female directors. Additionally, women show lower attendance than men at board meetings.

Theoretical/Academic Implications

The paper provides support for theories on the differences between the governance of family‐owned and non‐family‐owned companies.

Practitioner/Policy Implication

The study offers insights to policymakers implementing gender quota legislation. Substantial effort should be devoted to ensuring that board diversity is associated with actual independence of board members.
Analysis of edge crack behaviour influenced by non‐symmetrical contact tractions and bulk tension
Authors: Kim H.‐K.
Published: November 2014

This paper analyses a crack growth behaviour, which is initiated from the contact edge between a square punch with rounded edges and a half plane. Investigated are the influences of the contact profile, magnitude of the bulk tension and, crack obliquity, in particular, misalignment between the punch and half plane on the variation of the stress intensity factors KI and KII during the crack growth. The misalignment is simulated by a tilting of the punch. A partial slip regime is considered for the contact shear force to accommodate a general fretting fatigue condition. It was found that a crack closure occurs if only the contact forces are applied. The crack grows longer before it is closed if the punch is tilted (clockwise, in this paper) such that it initiates at the opposite site with respect to the direction of tilting. The closure phenomenon disappears when the bulk tension is added and exceeds a certain magnitude, which significantly depends on not only the contact profile but also the degree and direction of tilting. Provided are the lowest values of the bulk tensile stress due to a fatigue load necessary to extend the crack without a closure for each condition of the contact profile and misalignment. This may be used as a design guideline to restrain the contact‐induced failure.
The hippopotamus conveyor belt: vectors of carbon and nutrients from terrestrial grasslands to aquatic systems in sub‐Saharan Africa
Authors: Subalusky Amanda L. , Dutton Christopher L. , Rosi‐Marshall Emma J. , Post David M.
Published: November 2014

Hippopotami can play a significant role as ecosystem engineers and may play an important role as carbon and nutrient vectors from savanna grasslands to aquatic systems.

We coupled the results of a feeding study of captive hippopotami, faeces leaching/mineralisation experiments, hippopotamus consumption estimates and the stoichiometry of savanna grasses to calculate excretion and egestion rates of hippopotami. We then used time budgets and population estimates to calculate nutrient loading by hippopotami in the Mara River, Kenya.

In captivity, hippopotami consumed 11.0 g dry matter (DM) kg hippopotamus−1 day−1 (110.6 C; 6.8 N; 1.0 P) and egested 5.3 g DM kg−1 day−1. They excreted or egested 2.72 g C, 0.28 g N and 0.04 g P kg hippopotamus−1 day−1, and urine comprised 12% of C, 70% of N and 33% of P of total excretion and egestion.

By integrating data from previously published work on hippopotamus digestion with the data we collected in the field, we estimated an average hippopotamus in the Mara River would excrete or egest 1.93–3.58 g DM, 0.78–1.47 g C, 0.13–0.19 g N and 0.01–0.02 g P kg hippopotamus−1 day−1, and that half of this excretion/egestion would enter the river.

The hippopotamus population increased by 1500% inside the Maasai Mara National Reserve, Kenya, between 1959 and 2006. We estimate that hippopotami egest 36 200 kg faeces day−1 into the Mara River (wet mass). Daily loading into the river by excretion and egestion equals 8563 kg DM, 3499 kg C, 492 kg N and 48 kg P, which is equivalent to 670% of CPOM, 15% of DOC, 27% of TN and 29% of TP of loading from the upstream catchment.

This research provides the first estimates for hippopotamus inputs to rivers that include both excretion and egestion and provides evidence that hippopotami are important resource vectors in sub‐Saharan African rivers, even when compared to other sources of carbon and nutrients.
Multiple nutrient subsidy pathways from a spawning migration of iteroparous fish
Authors: Childress Evan S. , McIntyre Peter B.
Published: November 2014

Migratory animals can enhance ecosystem productivity through the delivery of material subsidies. Among fish, Pacific salmon are well known to deliver large quantities of nutrients to streams as they die after spawning, but the input pathways by which iteroparous species provide nutrient subsidies have not been resolved.

Our objective was to determine the importance of excretion, eggs and carcasses as nutrient sources from a large migration of longnose suckers into a stream draining a moderately agricultural catchment. Additionally, we evaluated nutrient limitation in the stream using nutrient‐diffusing substrates and determined the timing of nutrient releases during egg decomposition using a microcosm experiment.

Eggs were the largest component of the nitrogen (N, 57%) and phosphorus (P, 76%) inputs from the migration, followed by excretion by live adults (40% N, 16% P). Carcasses were a minor component of inputs.

Estimated P inputs from fish were over three times larger than the observed export of dissolved P in this P‐limited stream during the 66‐day sampling period. In contrast, sucker N inputs were <2% of dissolved N export, which was dominated by NO3. However, the dynamics of NH4 concentrations through the course of the migration were closely associated with estimated NH4 inputs from excretion and eggs.

Eggs and excretion constitute significant nutrient inputs during migrations, even in catchments with elevated nutrient loads from agriculture. Mass mortality is not required for migratory fish to enhance nutrient availability in their spawning habitats.

Given that sucker excretion rates and female reproductive investment are typical for freshwater fish, our results suggest that spawning migrations of iteroparous species in rivers around the world may deliver important nutrient subsidies when migrations are large.
The effects of flow and stream characteristics on the variation in freshwater mussel growth in a Southeast US river basin
Authors: Dycus Justin C. , Wisniewski Jason M. , Peterson James T.
Published: November 2014

The evaluation of the age and growth of animal populations is essential for understanding and predicting how populations will respond to changes in environmental conditions and anthropogenic stressors.

We used a novel, von Bertalanffy hierarchical modelling approach to quantify relationships between the growth of three freshwater mussel species and various site‐ and watershed‐level factors including seasonal discharge, land cover and stream size in the lower Flint River Basin, Georgia, U.S.A.

Our modelling approach quantified the mussel‐to‐mussel variation in the von Bertalanffy parameters and accounted for biases associated with multiple measurements made on each mussel specimen, which are generally not accounted for as sources of bias in age and growth studies.

Modelling results suggested that maximum shell size parameter and the Brody growth coefficient varied across species, on average, 19 and 33%, respectively, among individual mussels within sample sites. The variation was related to short‐term high streamflows during the spring season, stream size, channel geomorphology and land cover in the watershed.

This study provides insight to the factors affecting the growth of stream‐dwelling freshwater mussels. Although hierarchical von Bertalanffy growth models are rarely used for freshwater mussel age and growth studies, this approach can provide important information regarding the ecology of freshwater mussels.
Boron isotope geochemistry ofNa‐bicarbonate,Na‐chloride, andCa‐chloride waters from theNorthernApennineForedeep basin: other pieces of the sedimentary basin puzzle
Authors: Boschetti T. , Toscani L. , Salvioli Mariani E.
Published: November 2014

The boron stable isotope ratio δ11Bof 12 water samples representative of three chemical facies (freshNa‐bicarbonate, brackishNa‐chloride, saline, and brineCa‐chloride) has been analyzed. Interpretation of the δ11Bdata, along with the chemical compositions, reveals thatNa‐carbonate waters from theNorthernApennine are of meteoric origin, with boron contributions from clay desorption and mixing with seawater‐derived fluids ofNa‐chloride orCa‐chloride compositions. The comparison of our new results with the literature data on other sedimentary basins ofMediterranean, and worldwide, confirms the contribution ofNa‐bicarbonate waters to the genesis of mud volcano fluids. TheNa‐chloride sample ofSalvarola (SAL), which may represent the end‐member of the mud volcanoes, and theCa‐chloride brine water fromSalsomaggiore (SM) indicate boron release from clays compatible with the diagenetic process. The empirical equation:urn:x-wiley:14688115:media:gfl12124:gfl12124-math-0001relating boron concentration and the stable isotope composition of the fluids observed in this study and the literature is proposed to trace the effect of diagenesis in sedimentary basins. A geothermometer associated to the diagenetic equation is also proposed:urn:x-wiley:14688115:media:gfl12124:gfl12124-math-0002The application of this equation to obtain reservoir temperatures from δ11B compositions of waters should be carefully evaluated against the results obtained from other chemical and isotopic geothermometers from other basins around the world.