bluuebunny/crossref_metadata_2025 huggingface dataset:
Millimetre wave therapy for pain relief after total knee arthroplasty: A randomised controlled trial
Authors: Usichenko Taras I. , Edinger Hardy , Witstruck Torsten , Pavlovic Dragan , Zach Maria , Lange Joern , Gizhko Vasyl , Wendt Michael , Koch Bernhard , Lehmann Christian
Published: December 2007

Millimetre wave therapy (MWT) is a promising complementary method for pain relief, however rigorous investigations of its effectiveness are needed. The purpose of this study was to examine if MWT can reduce opioid requirement compared to sham procedure applied for relief of acute pain in patients after total knee arthroplasty (TKA). Eighty patients undergoing TKA were randomly assigned to receive MWT or sham procedure. Patients and evaluators were blinded to the group allocation. MWT consisted of six sessions, each session of 30min duration. During each session the knee wound was exposed to electromagnetic waves with frequency 50–75GHz and power density 4.2mW/cm2. Postoperative analgesia with piritramide, a weak opioid with 0.7 potency of morphine delivered via patient‐controlled analgesia pump, was directed to achieve pain intensity of less than 40 on a 100mm visual analogue scale (VAS). The primary outcome measure was postoperative piritramide requirement for three days after surgery. Secondary outcome measures were: total ibuprofen requirement from the fourth postoperative day to discharge; success of patients’ blinding; patients’ satisfaction with pain relief; incidence of analgesia‐related side effects; heart rate and blood pressure. Piritramide requirement was similar in both groups whereby all patients reported adequate pain relief measured on a VAS. Secondary outcome measures were also comparable in both groups. The majority of patients in both groups believed they had received true MWT and wanted to repeat it in future. Millimetre waves applied to surfaces of surgical wounds did not reduce opioid requirement compared to the sham procedure after TKA.
‘Munchausen's syndrome by proxy’ or a ‘miscarriage of justice’? An initial application of functional neuroimaging to the question of guilt versus innocence
Authors: Spence Sean A. , Kaylor-Hughes Catherine J. , Brook Martin L. , Lankappa Sudheer T. , Wilkinson Iain D.
Published: December 2007

‘Munchausen's syndrome by proxy’ characteristically describes women alleged to have fabricated or induced illnesses in children under their care, purportedly to attract attention. Where conclusive evidence exists the condition's aetiology remains speculative, where such evidence is lacking diagnosis hinges upon denial of wrong-doing (conduct also compatible with innocence). How might investigators obtain objective evidence of guilt or innocence? Here, we examine the case of a woman convicted of poisoning a child. She served a prison sentence but continues to profess her innocence. Using a modified fMRI protocol (previously published in 2001) we scanned the subject while she affirmed her account of events and that of her accusers. We hypothesized that she would exhibit longer response times in association with greater activation of ventrolateral prefrontal and anterior cingulate cortices when endorsing those statements she believed to be false (i.e., when she ‘lied’). The subject was scanned 4 times at 3 Tesla. Results revealed significantly longer response times and relatively greater activation of ventrolateral prefrontal and anterior cingulate cortices when she endorsed her accusers' version of events. Hence, while we have not ‘proven’ that this subject is innocent, we demonstrate that her behavioural and functional anatomical parameters behave as if she were.
Feline heartworm disease: A clinical review
Authors: Litster Annette L. , Atwell Richard B.
Published: December 2007

Feline heartworm disease is caused by the filarial nematode Dirofilaria immitis, and is transmitted by mosquitoes in heartworm-endemic areas worldwide. While dogs are the definitive hosts for this parasite, cats can also be infected, and the overall prevalence in cats is between 5% and 10% of that in dogs in any given area. The spectrum of feline presentations varies from asymptomatic infections to chronic respiratory signs, sometimes accompanied by chronic vomiting to acute death with no premonitory signs. Ante-mortem diagnosis can be challenging and relies on a combination of tests, including antigen and antibody serology, thoracic radiography and echocardiography. As treatment with heartworm adulticidal drugs can be life-threatening and heartworm infection in cats is often self-limiting, infected cats are frequently managed with supportive treatment (corticosteroids, bronchodilators, and anti-emetics). Surgical removal of filariae using extraction devices may be considered in some acute cases where immediate curative treatment is necessary, but filarial breakage during the procedure may result in an acute fatal shock-like reaction. Necropsy findings are mainly pulmonary and include muscular hypertrophy of the pulmonary arteries and arterioles on histopathology. A number of safe and effective macrocytic lactone drugs are available for prophylaxis in cats. These drugs can kill a range of larval and adult life-cycle stage heartworms, which may be advantageous in cases of owner compliance failure or when heartworm infection status is undetermined at the time prophylaxis is commenced. An index of suspicion for feline heartworm disease is warranted in unprotected cats with respiratory signs, and perhaps chronic vomiting, in areas where canine heartworm disease is endemic. Many cats, once diagnosed and with appropriate supportive care and monitoring, will resolve their infection and be free of clinical signs.
ISO 9000 practices and financial performance: A technology coherence perspective
Authors: Benner Mary J. , Veloso Francisco M.
Published: December 2007

Attention to processes has increased, as thousands of organizations have adopted process‐focused programs such as TQM and ISO 9000. Proponents of such programs stress the promise of improved efficiency and profitability. But research has not consistently borne out these prospects. Moreover, the expectation of universal benefits is not consistent with research highlighting the important role of firm‐specific capabilities in sustaining competitive advantage. In this paper, we use longitudinal panel data on ISO 9000 practices for firms in the auto supplier industry to study two new issues related to the adoption of process management practices. First, we find that, as the majority of firms within an industry adopt ISO 9000, late adopters no longer gain financial benefits from these practices. Second, we explore how firms’ technological coherence moderates the performance advantages of ISO 9000 practices. We find that firms that have a very narrow or very broad technological focus have fewer opportunities for complementary interactions that arise from process management practices and thus benefit less than those with limited breadth in technologically related activities.
Project success and project team management: Evidence from capital projects in the process industries
Authors: Scott‐Young Christina , Samson Danny
Published: December 2007

Efficient project execution is a key business objective in many domains and particularly so for capital projects in the process industries, but existing project management research gives little direction about how project team factors influence three important capital project outcomes: cost, schedule, and operability. After an extensive cross‐disciplinary review of the general team and project management literatures, we constructed and tested a theoretically based, five‐dimensional model of organizational context, project team design, project team leadership, project team processes, and project outcome factors. We examined the model by means of an empirical study of 56 newly completed capital projects executed by 15 Fortune 500 companies in the process industries. The results indicate the value of disaggregating project outcomes for research purposes. Different bundles of project team factors were found to drive project cost, schedule, and operability. Project team efficacy, cross‐functional project teams, autonomous project team structure, and virtual office usage were the strongest predictors of project cost effectiveness. Continuity of project leadership, cross‐functional project teams, and project manager incentives were the strongest predictors of project construction schedule. In contrast, clear project goals and an office design to facilitate effective communication were the main predictors of plant operability. Implications of these findings for researchers and project practitioners are discussed. One major practical implication of our findings is that project managers need to clearly focus and prioritize their goals for each project so they can adopt the appropriate bundles of project team practices that will facilitate their goal achievement.
On soil moisture–vegetation feedbacks and their possible effects on the dynamics of dryland ecosystems
Authors: D'Odorico Paolo , Caylor Kelly , Okin Gregory S. , Scanlon Todd M.
Published: December 2007

Soil moisture is the environmental variable synthesizing the effect of climate, soil, and vegetation on the dynamics of water‐limited ecosystems. Unlike abiotic factors (e.g., soil texture and rainfall regime), the control exerted by vegetation composition and structure on soil moisture variability remains poorly understood. A number of field studies in dryland landscapes have found higher soil water contents in vegetated soil patches than in adjacent bare soil, providing a convincing explanation for the observed preferential establishment of grasses and seedlings beneath tree canopies. Thus, because water is the limiting factor for vegetation in arid and semiarid ecosystems, a positive feedback could exist between soil moisture and woody vegetation dynamics. It is still unclear how the strength of such a feedback would change under different long‐term rainfall regimes. To this end, we report some field observations from savanna ecosystems located along the south‐north rainfall gradient in the Kalahari, where the presence of relatively uniform sandy soils limits the effects of covarying factors. The data available from our field study suggest that the contrast between the soil moisture in the canopy and intercanopy space increases (with wetter soils under the canopy) with increasing levels of aridity. We hypothesize that this contrast may lead to a positive feedback and explore the implications of such a feedback in a minimalistic model. We found that when the feedback is relatively strong, the system may exhibit two stable states corresponding to conditions with and without tree canopy cover. In this case, even small changes in environmental variables may lead to rapid and largely irreversible shifts to a state with no tree canopy cover. Our data suggest that the tendency of the system to exhibit two (alternative) stable states becomes stronger in the more arid regions. Thus, at the desert margins, vegetation is more likely to be prone to discontinuous and abrupt state changes.
Characterization of porosity in vapor-deposited amorphous solid water from methane adsorption
Authors: Raut U. , Famá M. , Teolis B. D. , Baragiola R. A.
Published: December 2007

We have characterized the porosity of vapor-deposited amorphous solid water (ice) films deposited at 30–40K using several complementary techniques such as quartz crystal microgravimetry, UV-visible interferometry, and infrared reflectance spectrometry in tandem with methane adsorption. The results, inferred from the gas adsorption isotherms, reveal the existence of microporosity in all vapor-deposited films condensed from both diffuse and collimated water vapor sources. Films deposited from a diffuse source show a step in the isotherms and much less adsorption at low pressures than films deposited from a collimated source with the difference increasing with film thickness. Ice films deposited from a collimated vapor source at 77° incidence are mesoporous, in addition to having micropores. Remarkably, mesoporosity is retained upon warming to temperatures as high as 140K where the ice crystallized. The binding energy distribution for methane adsorption in the micropores of ice films deposited from a collimated source peaks at ∼0.083eV for deposition at normal incidence and at ∼0.077eV for deposition at >45° incidence. For microporous ice, the intensity of the infrared bands due to methane molecules on dangling OH bonds on pore surfaces increases linearly with methane uptake, up to saturation adsorption. This shows that the multilayer condensation of methane does not occur inside the micropores. Rather, filling of the core volume results from coating the pore walls with the first layer of methane, indicating pore widths below a few molecular diameters. For ice deposited at 77° incidence, the increase in intensity of the dangling bond absorptions modified by methane adsorption departs from linearity at large uptakes.
Microwave spectra of O2–HF and O2–DF: Hyperfine interactions and global fitting with infrared data
Authors: Wu Shenghai , Sedo Galen , Grumstrup Erik M. , Leopold Kenneth R.
Published: December 2007

Spectra of the open shell complexes O2–HF and O2–DF were recorded using Fourier transform microwave spectroscopy. A complete analysis of the hyperfine structure and a global fit including microwave and infrared frequencies [W. M. Fawzy, C. M. Lovejoy, D. J. Nesbitt, and J. T. Hougen, J. Chem. Phys. 117, 693 (2002)] are reported. The Fermi contact interaction between the electron and nuclear spins, the electron spin-nuclear spin dipolar interaction, the nuclear spin-nuclear spin dipolar interaction, and the nuclear electric quadrupole interaction (for O2–DF) were considered in the analysis. The correspondence between the magnetic hyperfine constants and the two nuclei of the H(D)F is unambiguously established. In both O2–HF and O2–DF, the Fermi contact parameter is larger for the fluorine than for the hydrogen, while for the nuclear spin-electron spin dipolar hyperfine constants, the reverse is true. The effective angle between the HF bond and the a axis of the complex, determined from the nuclear spin-nuclear spin interaction constant, is 38(4)°. The same angle for the DF complex, derived from the deuterium nuclear quadrupole coupling constant, is 31(4)°.
Laser-Doppler vibrating tube densimeter for measurements at high temperatures and pressures
Authors: Aida Tsutomu , Yamazaki Ai , Akutsu Makoto , Ono Takumi , Kanno Akihiro , Hoshina Taka-aki , Ota Masaki , Watanabe Masaru , Sato Yoshiyuki , Smith Richard L. , Inomata Hiroshi
Published: December 2007

A laser-Doppler vibrometer was used to measure the vibration of a vibrating tube densimeter for measuring P-V-T data at high temperatures and pressures. The apparatus developed allowed the control of the residence time of the sample so that decomposition at high temperatures could be minimized. A function generator and piezoelectric crystal was used to excite the U-shaped tube in one of its normal modes of vibration. Densities of methanol-water mixtures are reported for at 673K and 40MPa with an uncertainty of 0.009g∕cm3.
Coherent control of bond breaking in amino acid complexes with tailored femtosecond pulses
Authors: Laarmann T. , Shchatsinin I. , Singh P. , Zhavoronkov N. , Gerhards M. , Schulz C. P. , Hertel I. V.
Published: December 2007

Intense femtosecond laser pulses, judiciously tailored in an adaptive, optimal control feedback loop were used to break preferentially the acyl-N (“peptide”) bond of Ac-Phe-NHMe that may be regarded as a dipeptide model. We show that coherent excitation of complex wave packets in the strong-field regime allows to cleave strong backbone bonds in the molecular system preferentially, while keeping other more labile bonds intact. These results show the potential of pulse shaping as a powerful complementary analytical tool for protein sequencing of large biopolymers in addition to the well-known mass spectrometry and chemical analysis.
Mechanical stress altered electron gate tunneling current and extraction of conduction band deformation potentials for germanium
Authors: Choi Youn Sung , Lim Ji-Song , Numata Toshinori , Nishida Toshikazu , Thompson Scott E.
Published: December 2007

Strain altered electron gate tunneling current is measured for germanium (Ge) metal–oxide–semiconductor devices with HfO2 gate dielectric. Uniaxial mechanical stress is applied using four-point wafer bending along [100] and [110] directions to extract both dilation and shear deformation potential constants of Ge. Least-squares fit to the experimental data results in Ξd and Ξu of −4.3±0.3 and 16.5±0.5 eV, respectively, which agree with theoretical calculations. The dominant mechanism for the strain altered electron gate tunneling current is a strain-induced change in the conduction band offset between Ge and HfO2. Tensile stress reduces the offset and increases the gate tunneling current for Ge while the opposite occurs for Si.
A model for vortex formation in magnetic nanodots
Authors: Leonel S. A. , Marques I. A. , Coura P. Z. , Costa B. V.
Published: December 2007

We use Monte Carlo simulation to study the vortex nucleation on magnetic nanodots at low temperature. In our simulations, we have considered a simple microscopic two-dimensional anisotropic Heisenberg model with term to describe the anisotropy due to the presence of the nanodot edge. We have considered the thickness of the edge, which was not considered in previous works, introducing a term that controls the energy associated to the edge. Our results clearly show that the thickness of the edge has a considerable influence in the vortex nucleation on magnetic nanodots. We have obtained the hysteresis curve for several values of the surface anisotropy and skin depth parameter (ξ). The results are in excellent agreement with experimental data.
Xenon ion laser-induced fluorescence using a visible tunable diode laser near 680nm
Authors: Severn Greg , Lee Dongsoo , Hershkowitz Noah
Published: December 2007

Laser-induced fluorescence (LIF) measurements have been performed for the first time in a low temperature (Te≈0.6eV) Xe plasma using a tunable diode laser in the visible range of wavelengths. The transition in Xe II involved the (P13)5d[3]7∕2 metastable state and the excitation wavelength was found to be 680.570±0.001nm (air). LIF measurements of I2 in a room temperature iodine gas cell were used to monitor the wavelength of the laser during the measurements.
Raman calibration of the HT-7 yttrium aluminum garnet Thomson scattering for electron density measurements
Authors: Zang Qing , Zhao Junyu , Gao Xiang , Shi Lingwei , Zhang Tao , Xi Xiaoqi , Yang Li , Hu Qingsheng , Sajjad S.
Published: December 2007

A multipulse neodym doped yttrium aluminum garnet laser Thomson scattering system calibrated by the anti-Stokes rotational Raman scattering from nitrogen gas had been developed in the HT-7 superconducting Tokmak. By virtue of this system, measured electron density results of the plasma were obtained. The results showed good repeatability and its total uncertainty was estimated to be ±18%.
Finite size effect on Néel temperature with Co3O4 nanoparticles
Authors: He Lin , Chen Chinping , Wang Ning , Zhou Wei , Guo Lin
Published: December 2007

The finite size effect on the antiferromagnetic transition temperature, TN, has been investigated with Co3O4 nanoparticles of 75, 35, and 16 nm in diameter. Along with the results from the previous experiments on the Co3O4 nanoparticles with average diameter of 8 and 4.3 nm, the variation of TN with the particle diameter, d, appears to follow the finite size scaling relation. The shift exponent is determined as λ=1.1±0.2 and the correlation length ξ0=2.8±0.3 nm. The value of the shift exponent is consistent with the description by the mean field theory.
Effect of the Er-Si interatomic distance on the Er3+ luminescence in silicon-rich silicon oxide thin films
Authors: Noé P. , Salem B. , Delamadeleine E. , Jalabert D. , Calvo V. , Maurizio C. , D’Acapito F.
Published: December 2007

The photoluminescence (PL) intensity of Er-doped silicon monoxide thin films obtained by coevaporation of silicon monoxide and Er is studied for different deposition and annealing atmosphere compositions. All samples exhibit a luminescence peak at 1.54 μm assigned to the radiative deexcitation of Er3+. PL intensity is highest when nitrogen atoms are incorporated in the layer during deposition. Extended x-ray absorption fine structure spectroscopy evidences that the local order around the erbium ion is modified in the presence of nitrogen. In particular, the shorter the Er-Si interatomic distance is, the higher the Er3+ PL intensity is.
Temperature dependence of cathodoluminescence spectra and stress analysis of a GaN layer grown on a mesa structured Si substrate
Authors: Xu Jun , Chen Li , Yu Lisheng , Liang H. , Zhang B. L. , Lau Kei May
Published: December 2007

The temperature dependence of cathodoluminescence (CL) spectra is measured on n-GaN grown on a Si (111) substrate patterned by deep etching in the temperature range 6–280 K. The temperature dependence of the peak energy of A free exciton (FXA) and its 1LO and 2LO phonon replicas are obtained. The stress distribution from corner to center in the patterned mesa area at low temperature 10 K is estimated roughly by FXA energy using a line scanning measurement of the CL spectra. The maximum tensile stress at a point far from the mesa edge is about 0.6 GPa and relaxed to 0.1 GPa at the corner. The relaxation distance extends to about 40 μm.
Process condition dependence of mechanical and physical properties of silicon nitride thin films
Authors: Walmsley B. A. , Keating A. J. , Liu Y. , Hu X. Z. , Bush M. B. , Dell J. M. , Faraone L.
Published: December 2007

This study uses a resonance method to determine Young’s modulus (E), shear modulus (G), and Poisson’s ratio (ν) of plasma-enhanced chemical vapor deposited silicon nitride (SiNxHy) thin films deposited under varying process conditions. The resonance method involves exciting the bending and torsional vibration modes of a microcantilever beam fabricated from a film. The E and G values can be extracted directly from the bending and torsional vibration modes, and the ν value can be determined from the calculated E and G values. The density (ρ) of the films was determined using a quartz crystal microbalance method. In order to determine the validity of the resonance method, finite element modeling was used to determine its dependence on microcantilever beam dimensions. Over a deposition temperature range of 100–300°C, measured E, G, and ν values varied within 54–193GPa, 22–77GPa, and 0.20–0.26 with changes in process conditions, respectively. Over the same deposition range, measured ρ values varied within 1.55–2.80g∕cm3 with changes in process conditions.
Quantum conductance in single- and double-wall carbon nanotube networks
Authors: Baxendale M. , Melli M. , Alemipour Z. , Pollini I. , Dennis T. J. S.
Published: December 2007

The electrical conductance of single- and double-wall carbon nanotube systems was measured by a mechanically controllable break-junction technique using freestanding nanotubes not subject to any chemical modification. For metallic single-wall carbon nanotubes, two channels with transmission coefficient of 0.88 contribute to ballistic electronic transport at room temperature. In double-wall carbon nanotubes, one metallic channel contributes to ballistic electronic transport and additional field- and temperature-dependent two-channel contributions were observed.
The effects of atmospheric pressure, air concentration in the fluid, and the surface roughness on the solid-sphere motion along a wall
Authors: Prokunin Alexander N.
Published: December 2007

A phenomenological model for describing a slow steady gravity-driven motion of a solid sphere down an inclined wall in a fluid under the conditions when an air (in the case of a fluid with dissolved air) bubble arises in the sphere-wall lubrication layer between the sphere and the wall is proposed. In the case under consideration, both contact and contactless motion of the sphere is possible. The sphere surface roughness and the concentration of the air dissolved in the fluid are taken into account. The relevant experiment studying the sphere motion accompanied by cavitation was carried out. We used fluids with various air concentration including a limiting case of degasified fluid and spheres of various surface roughness. We find a parameter whose constant value specifies a stationary motion of the sphere including a limiting case of degasified fluid. This parameter turns out to be proportional to the difference between atmospheric pressure and one corresponding to the equilibrium concentration of the air dissolved in fluid. The numerical results found were compared with the experimental data of our investigation and a good quantitative agreement was obtained in a certain domain of parameters. A possibility of unsteady motion of the sphere had been shown.
Ferroelectric and magnetic properties of Pb(Fe2∕3W1∕3)O3-based multiferroic compounds with cation order
Authors: Tan X. , Wongmaneerung R. , McCallum R. W.
Published: December 2007

Bi Fe O 3 and PbTiO3 were introduced to a Sc-modified Pb(Fe2∕3W1∕3)O3 compound with strong cation order to improve the multiferroic properties. It is found that the degree of cation order decreases as the amount of BiFeO3 or PbTiO3 increases. As a result, the saturation magnetization deteriorates. Solid solutions with BiFeO3 show an increase in both ferroelectric and magnetic transition temperatures. However, the ferroelectric remanent polarization is dramatically suppressed. In contrast, solid solution with PbTiO3 leads to an increase in the ferroelectric transition temperature, a decrease in the magnetic transition temperature, and a significant enhancement of remanent polarization. The composition 0.93[0.79Pb(Fe2∕3W1∕3)O3–0.21Pb(Sc2∕3W1∕3)O3]–0.07PbTiO3 shows the optimized properties of Tmax of 208K, Pr of 3.6μC∕cm2 between 120 and 210K, TN of 209K, and Ms of 0.23μB∕f.u. (3.7emu∕g) at 10K under 5T.
Complex dynamics of femtosecond terawatt laser pulses in air
Authors: Qiao Bin , Lai C. H. , Zhou C. T. , He X. T. , Wang Xingang
Published: December 2007

Complex dynamics of femtosecond terawatt laser pulses in air is investigated theoretically and numerically by considering both χ(5) susceptibility and multiphoton ionization. Our investigation shows that these two high-order nonlinearities, acting as a Hamiltonian perturbation, can destroy homoclinic orbit connection of phase trajectory and result in spatial chaos and complex pattern of laser wave field. Due to the chaotic behavior of laser field, laser filamentation appears when laser intensity increases close to the ionization threshold.
Phase structure of epitaxial Pb(Zr,Ti)O3 thin films on Nb-doped SrTiO3 substrates
Authors: Zhu Zhi-Xiang , Li Jing-Feng , Lai Feng-Ping , Zhen Yuhua , Lin Yuan-Hua , Nan Ce-Wen , Li Longtu , Li Jiangyu
Published: December 2007

Epitaxial Pb(Zr,Ti)O3 (PZT) films were deposited on Nb-doped SrTiO3 (Nb:STO) monocrystalline wafers by a sol-gel method. It was observed that phase structure of prepared films depends on the orientation of Nb:STO substrates. Interestingly, tetragonal structure was only found for [001]-oriented PZT film on Nb:STO(100) substrate, whereas Nb:STO(111) substrate resulted in a [111]-oriented rhombohedral PZT film, regardless of Zr∕Ti ratios ranging from 40∕60 to 60∕40. The influence of substrate orientation on phase structure of epitaxial PZT films was discussed on basis of the lattice matching. Ferroelectric and piezoelectric properties of PZT films on different Nb:STO substrates were also studied.
Semiconducting chains of gold and silver
Authors: Fioravante Frederico , Nunes R. W.
Published: December 2007

The authors introduce a geometry for ultrathin Au and Ag wires that ab initio calculations indicate to be more stable than previously considered planar geometries for these systems by about 0.1eV per atom. This structure is insulating for both metals and for related Ag0.5Au0.5 alloys with gaps of 1.3eV for Au, 0.8eV for Ag, and varying between 0.1 and 1.9eV for the alloys. The insulating nature of the geometry is not a result of Peierls instabilities and is analyzed in terms of an interplay between geometric and electronic structure effects.
Highly reflective MgAl alloy/Ag∕Ru Ohmic contact with low contact resistivity on p-type GaN
Authors: Lee S. , Son J. H. , Jung G. H. , Kim Y. G. , Kim C. Y. , Yoon Y. J. , Lee J.-L.
Published: December 2007

We report a metallization scheme of high-reflectance low-resistance Ohmic contact on p-type GaN. The high reflectance of 84% at 460nm wavelength and the specific contact resistivity as low as 8.59×10−6Ωcm2 were obtained from MgAl-alloy(50Å)∕Ag(3000Å)∕Ru(500Å) annealed at 450°C in air. The formation of Ag–Ga solid solution due to the outdiffusion of Ga after annealing leads to an Ohmic behavior of the contact. Employing highly reflective MgAl as a contact layer and Ru as an overlayer that suppress the agglomeration and the oxidation of the Ag result in the high reflectance of the contact.
Odour Perception: An Object-Recognition Approach
Authors: Stevenson Richard J , Wilson Donald A
Published: December 2007

Object recognition is a crucial component of both visual and auditory perception. It is also critical for olfaction. Most odours are composed of 10s or 100s of volatile components, yet they are perceived as unitary perceptual events against a continually shifting olfactory background (ie figure—ground segregation). We argue here that this occurs by rapid central adaptation to background odours combined with a pattern-matching system to recognise discrete sets of spatial and temporal olfactory features—an odour object. We present supporting neuropsychological, learning, and developmental evidence and then describe the neural circuitry which underpins this. The vagaries of an object-recognition approach are then discussed, with emphasis on the putative importance of memory, multimodal representations, and top—down processing.
Neural correlates of trust
Authors: Krueger Frank , McCabe Kevin , Moll Jorge , Kriegeskorte Nikolaus , Zahn Roland , Strenziok Maren , Heinecke Armin , Grafman Jordan
Published: December 2007

Trust is a critical social process that helps us to cooperate with others and is present to some degree in all human interaction. However, the underlying brain mechanisms of conditional and unconditional trust in social reciprocal exchange are still obscure. Here, we used hyperfunctional magnetic resonance imaging, in which two strangers interacted online with one another in a sequential reciprocal trust game while their brains were simultaneously scanned. By designing a nonanonymous, alternating multiround game, trust became bidirectional, and we were able to quantify partnership building and maintenance. Using within- and between-brain analyses, an examination of functional brain activity supports the hypothesis that the preferential activation of different neuronal systems implements these two trust strategies. We show that the paracingulate cortex is critically involved in building a trust relationship by inferring another person's intentions to predict subsequent behavior. This more recently evolved brain region can be differently engaged to interact with more primitive neural systems in maintaining conditional and unconditional trust in a partnership. Conditional trust selectively activated the ventral tegmental area, a region linked to the evaluation of expected and realized reward, whereas unconditional trust selectively activated the septal area, a region linked to social attachment behavior. The interplay of these neural systems supports reciprocal exchange that operates beyond the immediate spheres of kinship, one of the distinguishing features of the human species.
Risky Alcohol Consumption by Young, Female Australians: The Influence of Significant others
Authors: O'Hara Rebecca , Harker Debra , Raciti Maria , Harker Michael
Published: December 2007

This research used consumer behavior and social marketing principles to examine alcohol consumption among young female university students in Australia. Due to the high prevalence of risky alcohol consumption among this cohort, this study sought to examine the factors that influence the behavior of these individuals (Dowdall and Wechsler 2002; Shim and Maggs 2005). To date, this area of research has remained relatively unexplored. This article reports on the behavior of consumers in this cohort with a particular focus on reference group influence, in an attempt to make a contribution to future social marketing campaigns aimed at changing high risk behavior in the context of alcohol. The article also provides some insights into the possible components of a successful social marketing intervention program.
Effective Application of Knowledge Management in Evidence‐Based Chinese Medicine: A Case Study
Authors: Yang Angela Weihong , Allan Garry , Li Chun Guang , Xue Charlie Changli
Published: December 2007

Chinese medicine (CM) practice, as a knowledge‐based industry, has not embraced knowledge management (KM) techniques widely. However, KM may facilitate the adaptation and promotion of evidence‐based CM. A KM framework was introduced to its activities in evidence‐based CM through the development of a CM portal. A codification strategy was used to codify and store knowledge systematically in a database. Several approaches were developed and implemented to address specific needs for CM such as centralizing the information, encouraging collective efforts, promoting integration of explicit and tacit knowledge, and developing a flexible technology and support system. Following the established KM framework, the RMIT Chinese Medicine Portal (www.chinese‐medicine.com.au) was built up with four major components: organizational knowledge, knowledge workers, KM processes and information technology. Knowledge on Chinese herbs was classified into core, advanced and innovative categories, which involved the development of the monograph template. A working group was organized including CM, pharmacology and information technology professionals to implement this proposal with following sequential development stages: knowledge creation/acquisition, storage/organization, distribution and application. User interface and web language were also defined and accomplished. This case study demonstrates the applicability of KM in evidence‐based CM through a multidisciplinary collaboration, such as, an effective collaboration between CM and information technology. The study also shows the potential of KM application in other disciplines of complementary and alternative medicine.
Dissecting eIF4E action in tumorigenesis
Authors: Wendel Hans-Guido , Silva Ricardo L.A. , Malina Abba , Mills John R. , Zhu Hong , Ueda Takeshi , Watanabe-Fukunaga Rie , Fukunaga Rikiro , Teruya-Feldstein Julie , Pelletier Jerry , Lowe Scott. W.
Published: December 2007

Genetically engineered mouse models are powerful tools for studying cancer genes and validating targets for cancer therapy. We previously used a mouse lymphoma model to demonstrate that the translation initiation factor eIF4E is a potent oncogene in vivo. Using the same model, we now show that the oncogenic activity of eIF4E correlates with its ability to activate translation and become phosphorylated on Ser 209. Furthermore, constitutively activated MNK1, an eIF4E Ser 209 kinase, promotes tumorigenesis in a manner similar to eIF4E, and a dominant-negative MNK mutant inhibits the in vivo proliferation of tumor cells driven by mutations that deregulate translation. Phosphorylated eIF4E promotes tumorigenesis primarily by suppressing apoptosis and, accordingly, the anti-apoptotic protein Mcl-1 is one target of both phospho-eIF4E and MNK1 that contributes to tumor formation. Our results provide insight into how eIF4E contributes to tumorigenesis and pinpoint a level of translational control that may be suitable for therapeutic intervention.
Computational and experimental identification of novel human imprinted genes
Authors: Luedi Philippe P. , Dietrich Fred S. , Weidman Jennifer R. , Bosko Jason M. , Jirtle Randy L. , Hartemink Alexander J.
Published: December 2007

Imprinted genes are essential in embryonic development, and imprinting dysregulation contributes to human disease. We report two new human imprinted genes: KCNK9 is predominantly expressed in the brain, is a known oncogene, and may be involved in bipolar disorder and epilepsy, while DLGAP2 is a candidate bladder cancer tumor suppressor. Both genes lie on chromosome 8, not previously suspected to contain imprinted genes. We identified these genes, along with 154 others, based on the predictions of multiple classification algorithms using DNA sequence characteristics as features. Our findings demonstrate that DNA sequence characteristics, including recombination hot spots, are sufficient to accurately predict the imprinting status of individual genes in the human genome.
Lysigenous Aerenchyma Formation in Arabidopsis Is Controlled by LESION SIMULATING DISEASE1
Authors: Mühlenbock Per , Plaszczyca Malgorzata , Plaszczyca Marian , Mellerowicz Ewa , Karpinski Stanislaw
Published: December 2007

Aerenchyma tissues form gas-conducting tubes that provide roots with oxygen under hypoxic conditions. Although aerenchyma have received considerable attention in Zea mays, the signaling events and genes controlling aerenchyma induction remain elusive. Here, we show that Arabidopsis thaliana hypocotyls form lysigenous aerenchyma in response to hypoxia and that this process involves H2O2 and ethylene signaling. By studying Arabidopsis mutants that are deregulated for excess light acclimation, cell death, and defense responses, we find that the formation of lysigenous aerenchyma depends on the plant defense regulators LESION SIMULATING DISEASE1 (LSD1), ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1), and PHYTOALEXIN DEFICIENT4 (PAD4) that operate upstream of ethylene and reactive oxygen species production. The obtained results indicate that programmed cell death of lysigenous aerenchyma in hypocotyls occurs in a similar but independent manner from the foliar programmed cell death. Thus, the induction of aerenchyma is subject to a genetic and tissue-specific program. The data lead us to conclude that the balanced activities of LSD1, EDS1, and PAD4 regulate lysigenous aerenchyma formation in response to hypoxia.
A Viroid RNA with a Specific Structural Motif Inhibits Chloroplast Development
Authors: Rodio Maria-Elena , Delgado Sonia , De Stradis Angelo , Gómez María-Dolores , Flores Ricardo , Di Serio Francesco
Published: December 2007

Peach latent mosaic viroid (PLMVd) is a chloroplast-replicating RNA that propagates in its natural host, peach (Prunus persica), as a complex mixture of variants, some of which are endowed with specific structural and pathogenic properties. This is the case of variant PC-C40, with an insertion of 12 to 13 nucleotides that folds into a hairpin capped by a U-rich loop, which is responsible for an albino-variegated phenotype known as peach calico (PC). We have applied a combination of ultrastructural, biochemical, and molecular approaches to dissect the pathogenic effects of PC-C40. Albino sectors of leaves infected with variant PC-C40 presented palisade cells that did not completely differentiate into a columnar layer and altered plastids with irregular shape and size and with rudimentary thylakoids, resembling proplastids. Furthermore, impaired processing and accumulation of plastid rRNAs and, consequently, of the plastid translation machinery was observed in the albino sectors of leaves infected with variant PC-C40 but not in the adjacent green areas or in leaves infected by mosaic-inducing or latent variants (including PC-C40Δ, in which the 12- to 13-nucleotide insertion was deleted). Protein gel blot and RT-PCR analyses showed that the altered plastids support the import of nucleus-encoded proteins, including a chloroplast RNA polymerase, the transcripts of which were detected. RNA gel blot and in situ hybridizations revealed that PLMVd replicates in the albino leaf sectors and that it can invade the shoot apical meristem and induce alterations in proplastids, bypassing the RNA surveillance system that restricts the entry of a nucleus-replicating viroid and most RNA viruses. Therefore, a non-protein-coding RNA with a specific structural motif can interfere with an early step of the chloroplast developmental program, leading ultimately to an albino-variegated phenotype resembling that of certain variegated mutants in which plastid rRNA maturation is also impaired. Our results highlight the potential of viroids for further dissection of RNA trafficking and pathogenesis in plants.
The Central Cell Plays a Critical Role in Pollen Tube Guidance inArabidopsis
Authors: Chen Yan-Hong , Li Hong-Ju , Shi Dong-Qiao , Yuan Li , Liu Jie , Sreenivasan Rajini , Baskar Ramarmurthy , Grossniklaus Ueli , Yang Wei-Cai
Published: December 2007

The sperm cell of flowering plants cannot migrate unaided and must be transported by the pollen tube cell of the male gametophyte to achieve successful fertilization. Long-distance pollen tube guidance is controlled by the seven-celled female gametophyte, the embryo sac. Previous reports showed that the synergid cell of the embryo sac is essential for pollen tube guidance. Here, we report the identification of a central cell guidance (ccg) mutant, which is defective in micropylar pollen tube guidance. CCG encodes a nuclear protein with an N-terminal conserved zinc β-ribbon domain that is functionally interchangeable with that of TFIIB in yeast. This suggests that CCG might act as a transcription regulator for pollen tube guidance. CCG is expressed in the central cell of the female gametophyte. Expression of CCG in the central cell alone is sufficient to restore the normal pollen tube guidance phenotype, demonstrating that the central cell plays a critical role in pollen tube guidance.
BIN4, a Novel Component of the Plant DNA Topoisomerase VI Complex, Is Required for Endoreduplication in Arabidopsis
Authors: Breuer Christian , Stacey Nicola J. , West Christopher E. , Zhao Yunde , Chory Joanne , Tsukaya Hirokazu , Azumi Yoshitaka , Maxwell Anthony , Roberts Keith , Sugimoto-Shirasu Keiko
Published: December 2007

How plant organs grow to reach their final size is an important but largely unanswered question. Here, we describe an Arabidopsis thaliana mutant, brassinosteroid-insensitive4 (bin4), in which the growth of various organs is dramatically reduced. Small organ size in bin4 is primarily caused by reduced cell expansion associated with defects in increasing ploidy by endoreduplication. Raising nuclear DNA content in bin4 by colchicine-induced polyploidization partially rescues the cell and organ size phenotype, indicating that BIN4 is directly and specifically required for endoreduplication rather than for subsequent cell expansion. BIN4 encodes a plant-specific, DNA binding protein that acts as a component of the plant DNA topoisomerase VI complex. Loss of BIN4 triggers an ATM- and ATR-dependent DNA damage response in postmitotic cells, and this response coincides with the upregulation of the cyclin B1;1 gene in the same cell types, suggesting a functional link between DNA damage response and endocycle control.
Photosystem II Assembly and Repair Are Differentially Localized inChlamydomonas
Authors: Uniacke James , Zerges William
Published: December 2007

Many proteins of the photosynthesis complexes are encoded by the genome of the chloroplast and synthesized by bacterium-like ribosomes within this organelle. To determine where proteins are synthesized for the de novo assembly and repair of photosystem II (PSII) in the chloroplast of Chlamydomonas reinhardtii, we used fluorescence in situ hybridization, immunofluorescence staining, and confocal microscopy. These locations were defined as having colocalized chloroplast mRNAs encoding PSII subunits and proteins of the chloroplast translation machinery specifically under conditions of PSII subunit synthesis. The results revealed that the synthesis of the D1 subunit for the repair of photodamaged PSII complexes occurs in regions of the chloroplast with thylakoids, consistent with the current model. However, for de novo PSII assembly, PSII subunit synthesis was detected in discrete regions near the pyrenoid, termed T zones (for translation zones). In two PSII assembly mutants, unassembled D1 subunits and incompletely assembled PSII complexes localized around the pyrenoid, where we propose that they mark an intermediate compartment of PSII assembly. These results reveal a novel chloroplast compartment that houses de novo PSII biogenesis and the regulated transport of newly assembled PSII complexes to thylakoid membranes throughout the chloroplast.
Cell-Fate Switch of Synergid to Egg Cell inArabidopsis eostreMutant Embryo Sacs Arises from Misexpression of the BEL1-Like Homeodomain GeneBLH1
Authors: Pagnussat Gabriela Carolina , Yu Hee-Ju , Sundaresan Venkatesan
Published: December 2007

In Arabidopsis thaliana, the female gametophyte is a highly polarized structure consisting of four cell types: one egg cell and two synergids, one central cell, and three antipodal cells. In this report, we describe the characterization of a novel female gametophyte mutant, eostre, which affects establishment of cell fates in the mature embryo sac. The eostre phenotype is caused by misexpression of the homeodomain gene BEL1-like homeodomain 1 (BLH1) in the embryo sac. It is known that BELL-KNAT proteins function as heterodimers whose activities are regulated by the Arabidopsis ovate family proteins (OFPs). We show that the phenotypic effect of BLH1 overexpression is dependent upon the class II knox gene KNAT3, suggesting that KNAT3 must be expressed and functional during megagametogenesis. Moreover, disruption of At OFP5, a known interactor of KNAT3 and BLH1, partially phenocopies the eostre mutation. Our study indicates that suppression of ectopic activity of BELL-KNOX TALE complexes, which might be mediated by At OFP5, is essential for normal development and cell specification in the Arabidopsis embryo sac. As eostre-1 embryo sacs also show nuclear migration abnormalities, this study suggests that a positional mechanism might be directing establishment of cell fates in early megagametophyte development.
Bibliotek.dk: opening the Danish union catalogue to the public
Authors: Larsen Kirsten
Published: December 2007

Purpose

The purpose of this paper is to give an overview of the development of bibliotek.dk (library.dk) – how to open a union catalogue to the public.

Design/methodology/approach

bibliotek.dk – the end‐user web interface to the public union catalogue is described and challenges in these features are examined: the user interface, end‐user loan requests, cooperation with Google, library 2.0 characteristics etc. Usage statistics are presented.

Findings

It was found that it is possible to make requesting library material (almost) as easy and fast as searching Google.

Originality/value

The paper will be of interest to librarians working with opening their services to the public.