bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-dimensional loop quantum gravity: Particles and the quantum double
Authors: Noui Karim
Published: October 2006

It is well known that the quantum double structure plays an important role in three-dimensional quantum gravity coupled to matter field. In this paper, we show how this algebraic structure emerges in the context of three-dimensional Riemannian loop quantum gravity (LQG) coupled to a finite number of massive spinless point particles. In LQG, physical states are usually constructed from the notion of SU(2) cylindrical functions on a Riemann surfaced Σ and the Hilbert structure is defined by the Ashtekar-Lewandowski measure. In the case where Σ is the sphere S2, we show that the physical Hilbert space is in fact isomorphic to a tensor product of simple unitary representations of the Drinfeld double DSU(2): the masses of the particles label the simple representations, the physical states are tensor products of vectors of simple representations, and the physical scalar product is given by intertwining coefficients between simple representations. This result is generalized to the case of any Riemann surface Σ.
Strain-controlled correlation effects in self-assembled quantum dot stacks
Authors: Kunert R. , Schöll E.
Published: October 2006

The authors show that elastic interactions of an array of self-assembled quantum dots in a parent material matrix are markedly distinct from the elastic field created by a single point defect and can explain the observed abrupt correlation-anticorrelation transition in semiconductor quantum dot stacks. Finite volume effects of the quantum dots are shown to lead to sharper transitions. Their analysis also predicts the inclination angle under which the alignment in successive quantum dot layers occurs in dependence on the material anisotropy.
Effects of microsolvation on uracil and its radical anion: Uracil∙(H2O)n (n=1–5)
Authors: Kim Sunghwan , Schaefer Henry F.
Published: October 2006

Microsolvation effects on the stabilities of uracil and its anion have been investigated by explicitly considering the structures of complexes of uracil with up to five water molecules at the B3LYP∕DZP++ level of theory. For all five systems, the global minimum of the neutral cluster has a different equilibrium geometry from that of the radical anion. Both the vertical detachment energy (VDE) and adiabatic electron affinity (AEA) of uracil are predicted to increase gradually with the number of hydrating molecules, qualitatively consistent with experimental results from a photodetachment-photoelectron spectroscopy study [J. Schiedt et al., Chem. Phys. 239, 511 (1998)]. The trend in the AEAs implies that while the conventional valence radical anion of uracil is only marginally bound in the gas phase, it will form a stable anion in aqueous solution. The gas-phase AEA of uracil (0.24eV) was higher than that of thymine by 0.04eV and this gap was not significantly affected by microsolvation. The largest AEA is that predicted for uracil∙(H2O)5, namely, 0.96eV. The VDEs range from 0.76to1.78eV.
Wave-breaking injection of electrons to a laser wake field in plasma channels at the strong focusing regime
Authors: Ohkubo T. , Bulanov S. V. , Zhidkov A. G. , Esirkepov T. , Koga J. , Uesaka M. , Tajima T.
Published: October 2006

Efficient and fast self-injection of plasma electrons into the wake-field acceleration phase can be procured during the transverse wake-wave breaking when the wake-wave is generated by the high-intensity laser pulse propagating in a narrow plasma channel. In the strong focusing regime, when the laser pulse power exceeds critical for the self-focusing power threshold, the injected electron bunch length becomes comparable with the plasma wavelength and the bunch has the femtosecond duration. The total charge of self-injected electrons depends strongly on the laser pulse amplitude.
Theoretical direct correlation function for two-dimensional fluids of monodisperse hard spheres
Authors: Guo Xiaoai , Riebel Ulrich
Published: October 2006

The direct correlation function plays an important role in describing the effects of the structure of particle systems with respect to light diffraction, x-ray diffraction as well as transmission and transmission fluctuations of radiation through a dense suspension. In this paper, the direct correlation function for a monolayer of monodisperse hard spheres or disks is derived theoretically. Based on the approximation of Baus and Colot [Phys. Rev. A 36, 3912 (1987)] and the equation of state for a fluid of hard disks by Santos et al. [J. Chem. Phys. 103, 4622 (1995)], we propose a new direct correlation function, which compares well to the approximate analytical expressions and gives a good prediction of the structure factor in a wide range of monolayer density or suspension concentration. The resulting radial distribution function also agrees well with Monte Carlo computer simulation data. The corresponding contact values of the radial distribution function compare well with the results of analytic approximations, numerical solutions, and computer simulations. Our proposed direct correlation function is applied to the transmission fluctuation spectrometric study. Experimental results show good agreement with the theory.
A quantitative account of quantum effects in liquid water
Authors: Fanourgakis G. S. , Schenter G. K. , Xantheas S. S.
Published: October 2006

We report converged quantum statistical mechanical simulations of liquid water with the Thole-type Model (version 2.1), Flexible, polarizable (TTM2.1-F) interaction potential for water. Simulations of total length of 600ps with a 0.05fs time step for a periodic unit cell of 256 molecules with up to 32 replicas per atom suggest that the quantum effects contribute 1.01±0.02kcal∕mol to the liquid enthalpy of formation at 298.15K. They furthermore demonstrate for the first time a quantitative agreement with experiment for the heights and broadening of the intramolecular OH and HH peaks in the radial distribution functions.
All-angle negative refraction and evanescent wave amplification using one-dimensional metallodielectric photonic crystals
Authors: Shin Hocheol , Fan Shanhui
Published: October 2006

The authors numerically demonstrate all-angle negative refraction for propagating waves, as well as evanescent wave amplifications, using a one-dimensional photonic crystal consisting of metal-dielectric multilayers. Their structure has uniform surfaces parallel to the object plane and operates at the visible wavelength range. Using realistic material parameters including loss, they design a Ag–Si3N4 multilayer structure and verified its subwavelength resolution in the image formation process.
Strong configurational dependence of elastic properties for a binary model metallic glass
Authors: Duan Gang , Lind Mary Laura , Demetriou Marios D. , Johnson William L. , Goddard William A. , Çaģin Tahir , Samwer Konrad
Published: October 2006

In this work, the strong dependence of elastic properties on configurational changes in a Cu–Zr binary metallic glass assessed by molecular dynamics simulations is reported. By directly evaluating the temperature dependence and configurational potential energy dependence of elastic constants, the shear modulus dependence on the specific configurational inherent state of metallic glasses is shown to be much stronger than the dependence on Debye-Grüneisen thermal expansion.
Enhanced performance of white polymer light-emitting diodes using polymer blends as hole-transporting layers
Authors: Sun Q. J. , Hou J. H. , Yang C. H. , Li Y. F. , Yang Y.
Published: October 2006

AU: PLEASE CONFIRM CHANGES MADE IN THE BYLINE.White polymer light-emitting diodes (WPLEDs) with the Commission Internationale de l’Enclairage coordinates of (0.32, 0.34) are demonstrated with poly(9,9-dioctylfluorene-2,7-diyl) as host and poly(5-methoxy-2-(2′-ethyl-hexylthio)-p-phenylenevinylene) as guest. Blends of poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine] (poly-TPD) and poly(N-vinyl-carbazole) (PVK) are introduced into bilayer devices as hole-transporting layers (HTLs). Because the blends combined the hole-injection and hole-transporting capabilities of poly-TPD with electron-blocking capability of PVK, WPLEDs with the blends as HTLs exhibit enhanced performance in comparison with single-layer device and bilayer devices with pure poly-TPD or pure PVK as HTL. With a 1:1 weight ratio of poly-TPD to PVK in the blend, the WPLED achieves a maximum brightness of ∼5000cd∕m2 with a maximum electroluminescent efficiency of 3.15cd∕A.
Asymmetric long period fiber gratings fabricated by use of CO2 laser to carve periodic grooves on the optical fiber
Authors: Wang Yi-Ping , Wang D. N. , Jin Wei , Rao Yun-Jiang , Peng Gang-Ding
Published: October 2006

An asymmetric long period fiber grating (LPFG) with a large attenuation of −47.39dB and a low insertion loss of 0.34dB is fabricated by use of focused CO2 laser beam to carve periodic grooves on one side of the optical fiber. Such periodic grooves and the stretch-induced periodic microbends can effectively enhance the refractive index modulation and increase the average strain sensitivity of the resonant wavelength of the LPFG to −102.89nm∕mε. The resonant wavelength and the peak attenuation of the LPFG can be tuned by ∼12nm and ∼20dB, respectively, by the application of a stretching force.
Time resolved photocurrent, microwave spectrum, and multiple high-field domains in dc-biased GaAs
Authors: Kašalynas I. , Subačius L.
Published: October 2006

The authors present an experimental study of the time resolved photocurrent and its Fourier spectrum in dc-biased semi-insulating GaAs under multiple high-field domains photoexcitation. It is observed that nanosecond duration light interference pattern induces subnanosecond instabilities on the falling slope of the photocurrent pulse only when the external dc field reaches a threshold field value, i.e., when a transient multi-domain structure drifting through the spatially modulated semiconductor is generated. The signal spectrum in the gigahertz range is broad but, if system parameters are set properly, the spectrum becomes stable and concentrated at a single frequency proportional to the spatial period of the light interference pattern and the drift velocity of the domains.
Spin-polarized inelastic electron tunneling spectroscopy of a molecular magnetic tunnel junction
Authors: Wang Wenyong , Richter Curt A.
Published: October 2006

Molecular electronic devices with spin-dependent tunneling transport behavior offer an innovative and extremely enticing direction towards spin electronics, both from fundamental and technological points of view. In this work, inelastic electron tunneling spectroscopy provides unambiguous experimental evidence of the existence of molecular species in the fabricated molecular magnetic tunnel devices. Tunneling spectroscopy is also utilized to investigate the spin-polarized inelastic electron tunneling processes in the molecular device. The results show that inelastic scattering due to molecular vibrations, instead of magnon excitations, may be the main cause of the observed junction magnetoresistance bias dependence.
Band structure of the epitaxial Fe∕MgO∕GaAs(001) tunnel junction studied by x-ray and ultraviolet photoelectron spectroscopies
Authors: Lu Y. , Le Breton J. C. , Turban P. , Lépine B. , Schieffer P. , Jézéquel G.
Published: October 2006

The electronic band structure in the epitaxial Fe∕MgO∕GaAs(001) tunnel junction has been studied by x-ray and ultraviolet photoelectron spectroscopy measurements. The Schottky barrier height (SBH) of Fe on MgO∕GaAs heterostructure is determined to be 3.3±0.1eV, which sets the Fe Fermi level at about 0.3eV above the GaAs valence band maximum. This SBH is also exactly the same as that measured from Fe on MgO monocrystal. After Fe deposition, no band bending change is observed in MgO and GaAs underlayers. On the contrary, Au and Al depositions led to clear variation of the band bending in both MgO and GaAs layers. This effect is analyzed as a fingerprint of defect states at the MgO∕GaAs interface.
An 85-aa segment of the GB virus type C NS5A phosphoprotein inhibits HIV-1 replication in CD4
+
Jurkat T cells
Authors: Xiang Jinhua , McLinden James H. , Chang Qing , Kaufman Thomas M. , Stapleton Jack T.
Published: October 2006

GB virus type C (GBV-C) is an apparently nonpathogenic virus that replicates in T and B lymphocytes and is a common cause of persistent human infection. Among HIV-1-infected individuals, persistent coinfection with GBV-C is associated with prolonged survival, and infection of blood mononuclear cells or CD4
+
T cells with GBV-C and HIV
in vitro
results in significantly reduced HIV-1 replication. To date, the viral protein(s) that lead to HIV inhibition have not been identified. The GBV-C nonstructural phosphoprotein (NS5A) is predicted to have pleotropic effects on cells, including interactions with the IFN-induced dsRNA-activated protein kinase (PKR). We studied GBV-C NS5A to determine whether it is involved in inhibition of HIV replication. GBV-C NS5A protein from an isolate that was cleared by IFN therapy did not inhibit PKR, whereas NS5A from an isolate that was not cleared by IFN-inhibited PKR function in a yeast genetic system. Both of these GBV-C NS5A proteins were expressed in a CD4
+
T cell line (Jurkat), and both induced a potent, dose-dependent inhibition of HIV-1 replication, thus the effect was independent of PKR inhibition. NS5A induced the release of the chemokine SDF-1 and decreased surface expression of the HIV coreceptor CXCR4, potentially explaining the HIV inhibition. Deletion mapping of the NS5A protein found that an 85-aa region between amino acids 152 and 237 inhibits HIV-1 replication. Thus, GBV-C NS5A protein alters the cellular milieu necessary for HIV-1 replication and may provide a previously undescribed therapeutic approach for anti-HIV therapy.
Cell-surface heparan sulfate proteoglycans are essential components of the unconventional export machinery of FGF-2
Authors: Zehe Christoph , Engling André , Wegehingel Sabine , Schäfer Tobias , Nickel Walter
Published: October 2006

FGF-2 is an unconventionally secreted lectin that transmits proangiogenic signals through a ternary complex with high-affinity FGF receptors and heparan sulfate proteoglycans (HSPGs). Although FGF-2 signal transduction is understood in great detail, its mechanism of release from cells, which is independent of the classical secretory pathway, remains elusive. To test the hypothesis that FGF-2 secretion is linked to its cell-surface ligands, we studied FGF-2 release using mutants defective for HSPG binding and cells with impaired HSPG biosynthesis. Here, we report that a functional interaction between FGF-2 and HSPGs is required for net export of FGF-2 from mammalian cells. FGF-2 release requires extracellular, membrane-proximal HSPGs. We propose that extracellular HSPGs form a molecular trap that drives FGF-2 translocation across the plasma membrane.
Burkholderia xenovorans
LB400 harbors a multi-replicon, 9.73-Mbp genome shaped for versatility
Authors: Chain Patrick S. G. , Denef Vincent J. , Konstantinidis Konstantinos T. , Vergez Lisa M. , Agulló Loreine , Reyes Valeria Latorre , Hauser Loren , Córdova Macarena , Gómez Luis , González Myriam , Land Miriam , Lao Victoria , Larimer Frank , LiPuma John J. , Mahenthiralingam Eshwar , Malfatti Stephanie A. , Marx Christopher J. , Parnell J. Jacob , Ramette Alban , Richardson Paul , Seeger Michael , Smith Daryl , Spilker Theodore , Sul Woo Jun , Tsoi Tamara V. , Ulrich Luke E. , Zhulin Igor B. , Tiedje James M.
Published: October 2006

Burkholderia xenovorans
LB400 (LB400), a well studied, effective polychlorinated biphenyl-degrader, has one of the two largest known bacterial genomes and is the first nonpathogenic
Burkholderia
isolate sequenced. From an evolutionary perspective, we find significant differences in functional specialization between the three replicons of LB400, as well as a more relaxed selective pressure for genes located on the two smaller vs. the largest replicon. High genomic plasticity, diversity, and specialization within the
Burkholderia
genus are exemplified by the conservation of only 44% of the genes between LB400 and
Burkholderia cepacia
complex strain 383. Even among four
B. xenovorans
strains, genome size varies from 7.4 to 9.73 Mbp. The latter is largely explained by our findings that >20% of the LB400 sequence was recently acquired by means of lateral gene transfer. Although a range of genetic factors associated with
in vivo
survival and intercellular interactions are present, these genetic factors are likely related to niche breadth rather than determinants of pathogenicity. The presence of at least eleven “central aromatic” and twenty “peripheral aromatic” pathways in LB400, among the highest in any sequenced bacterial genome, supports this hypothesis. Finally, in addition to the experimentally observed redundancy in benzoate degradation and formaldehyde oxidation pathways, the fact that 17.6% of proteins have a better LB400 paralog than an ortholog in a different genome highlights the importance of gene duplication and repeated acquirement, which, coupled with their divergence, raises questions regarding the role of paralogs and potential functional redundancies in large-genome microbes.
Protein folding is slaved to solvent motions
Authors: Frauenfelder H. , Fenimore P. W. , Chen G. , McMahon B. H.
Published: October 2006

Proteins, the workhorses of living systems, are constructed from chains of amino acids, which are synthesized in the cell based on the instructions of the genetic code and then folded into working proteins. The time for folding varies from microseconds to hours. What controls the folding rate is hotly debated. We postulate here that folding has the same temperature dependence as the α-fluctuations in the bulk solvent but is much slower. We call this behavior slaving. Slaving has been observed in folded proteins: Large-scale protein motions follow the solvent fluctuations with rate coefficient

k
α

but can be slower by a large factor. Slowing occurs because large-scale motions proceed in many small steps, each determined by

k
α

. If conformational motions of folded proteins are slaved, so a fortiori must be the motions during folding. The unfolded protein makes a Brownian walk in the conformational space to the folded structure, with each step controlled by

k
α

. Because the number of conformational substates in the unfolded protein is extremely large, the folding rate coefficient, k
f
, is much smaller than

k
α

. The slaving model implies that the activation enthalpy of folding is dominated by the solvent, whereas the number of steps

n
f

=

k
α

/

k
f

is controlled by the number of accessible substates in the unfolded protein and the solvent. Proteins, however, undergo not only α- but also β-fluctuations. These additional fluctuations are local protein motions that are essentially independent of the bulk solvent fluctuations and may be relevant at late stages of folding.
G protein-coupled receptors sense fluid shear stress in endothelial cells
Authors: Chachisvilis Mirianas , Zhang Yan-Liang , Frangos John A.
Published: October 2006

Hemodynamic shear stress stimulates a number of intracellular events that both regulate vessel structure and influence development of vascular pathologies. The precise molecular mechanisms by which endothelial cells transduce this mechanical stimulus into intracellular biochemical response have not been established. Here, we show that mechanical perturbation of the plasma membrane leads to ligand-independent conformational transitions in a G protein-coupled receptor (GPCR). By using time-resolved fluorescence microscopy and GPCR conformation-sensitive FRET we found that stimulation of endothelial cells with fluid shear stress, hypotonic stress, or membrane fluidizing agent leads to a significant increase in activity of bradykinin B
2
GPCR in endothelial cells. The GPCR conformational dynamics was detected by monitoring redistribution of GPCRs between inactive and active conformations in a single endothelial cell under fluid shear stress in real time. We show that this response can be blocked by a B
2
-selective antagonist. Our data demonstrate that changes in cell membrane tension and membrane fluidity affect conformational dynamics of GPCRs. Therefore, we suggest that GPCRs are involved in mediating primary mechanochemical signal transduction in endothelial cells. We anticipate our experiments to be a starting point for more sophisticated studies of the effects of changes in lipid bilayer environment on GPCR conformational dynamics. Furthermore, because GPCRs are a major target of drug development, a detailed characterization of mechanochemical signaling via the GPCR pathway will be relevant for the development of new antiatherosclerosis drugs.
Hypothalamic malonyl-CoA triggers mitochondrial biogenesis and oxidative gene expression in skeletal muscle: Role of PGC-1α
Authors: Cha Seung-Hun , Rodgers Joseph T. , Puigserver Pere , Chohnan Shigeru , Lane M. Daniel
Published: October 2006

Previous investigations show that intracerebroventricular administration of a potent inhibitor of fatty acid synthase, C75, increases the level of its substrate, malonyl-CoA, in the hypothalamus. The “malonyl-CoA signal” is rapidly transmitted to skeletal muscle by the sympathetic nervous system, increasing fatty acid oxidation, uncoupling protein-3 (UCP3) expression, and thus, energy expenditure. Here, we show that intracerebroventricular or intraperitoneal administration of C75 increases the number of mitochondria in white and red (soleus) skeletal muscle. Consistent with signal transmission from the hypothalamus by the sympathetic nervous system, centrally administered C75 rapidly (≤2 h) up-regulated the expression (in skeletal muscle) of the β-adrenergic signaling molecules, i.e., norepinephrine, β
3
-adrenergic receptor, and cAMP; the transcriptional regulators peroxisomal proliferator activator regulator γ coactivator 1α (PGC-1α) and estrogen receptor-related receptor α (ERRα); and the expression of key oxidative mitochondrial enzymes, including pyruvate dehydrogenase kinase, medium-chain length fatty acyl-CoA dehydrogenase, ubiquinone–cytochrome
c
reductase, cytochrome oxidase, as well as ATP synthase and UCP3. The role of PGC-1α in mediating these responses in muscle was assessed with C2C12 myocytes in cell culture. Consistent with the
in vivo
response, adenovirus-directed expression of PGC-1α in C2C12 muscle cells provoked the phosphorylation/inactivation and reduced expression of acetyl-CoA carboxylase 2, causing a reduction of the malonyl-CoA concentration. These effects, coupled with an increased carnitine palmitoyltransferase 1b, led to increased fatty acid oxidation. PGC-1α also increased the expression of ERRα, PPARα, and enzymes that support mitochondrial fatty acid oxidation, ATP synthesis, and thermogenesis, apparently mediated by an increased expression of UCP3.
Integrin signaling is critical for pathological angiogenesis
Authors: Mahabeleshwar Ganapati H. , Feng Weiyi , Phillips David R. , Byzova Tatiana V.
Published: October 2006

The process of postnatal angiogenesis plays a crucial role in pathogenesis of numerous diseases, including but not limited to tumor growth/metastasis, diabetic retinopathy, and in tissue remodeling upon injury. However, the molecular events underlying this complex process are not well understood and numerous issues remain controversial, including the regulatory function of integrin receptors. To analyze the role of integrin phosphorylation and signaling in angiogenesis, we generated knock-in mice that express a mutant β3 integrin unable to undergo tyrosine phosphorylation. Two distinct models of pathological angiogenesis revealed that neovascularization is impaired in mutant β3 knock-in mice. In an ex vivo angiogenesis assay, mutant β3 knock-in endothelial cells did not form complete capillaries in response to vascular endothelial growth factor (VEGF) stimulation. At the cellular level, defective tyrosine phosphorylation in mutant β3 knock-in cells resulted in impaired adhesion, spreading, and migration of endothelial cells. At the molecular level, VEGF stimulated complex formation between VEGF receptor-2 and β3 integrin in wild-type but not in mutant β3 knock-in endothelial cells. Moreover, phosphorylation of VEGF receptor-2 was significantly reduced in cells expressing mutant β3 compared to wild type, leading to impaired integrin activation in these cells. These findings provide novel mechanistic insights into the role of integrin–VEGF axis in pathological angiogenesis.
Full of sound and fury, but signifying something: XVI International AIDS Conference, Toronto, Canada, August 13-18, 2006
Authors: Wells William A.
Published: October 2006

The biennial AIDS conference is often exhausting and irritating, but it offers a unique view of how science and society interact. It still deserves the support of basic scientists.
The growth of government spending and the money supply
Authors: Kandil Magda
Published: October 2006

Purpose

Using quarterly data for a sample of 17 industrial countries, the purpose of this paper is to study asymmetry in the face of monetary shocks compared to government spending shocks.

Design/methodology/approach

The paper outlines demand and supply channels determining the asymmetric effects of monetary and fiscal policies. The time‐series model is presented and an analysis of the difference in the asymmetric effects of monetary and fiscal shocks within countries is presented. There then follows an investigation of the relevance of demand and supply conditions to the asymmetric effects of monetary and fiscal shocks. The implications of asymmetry are contrasted across countries.

Findings

Fluctuations in real output growth, price inflation, wage inflation, and real wage growth vary with respect to anticipated and unanticipated shifts to the money supply, government spending, and the energy price. The asymmetric flexibility of prices appears a major factor in differentiating the expansionary and contractionary effects of fiscal and monetary shocks. Higher price inflation, relative to deflation, exacerbates output contraction, relative to expansion, in the face of monetary shocks. In contrast, larger price deflation, relative to inflation, moderates output contraction, relative to expansion in the face of government spending shocks. The growth of output and the real wage decreases, on average, in the face of monetary variability in many countries. Moreover, the growth of real output and the real wage increases, on average, in the face of government spending variability in many countries. Asymmetry differentiates the effects of monetary and government spending shocks within and across countries. The degree and direction of asymmetry provide a new dimension to differentiate between monetary and fiscal tools in the design of stabilization policies.

Originality/value

The paper's evidence sheds light on the validity of theoretical models explaining asymmetry in the effects of demand‐side stabilization policies. Moreover, the evidence should alert policy makers to the need to relax structural and institutional constraints to maximize the benefits of stabilization policies and minimize the adverse effects on economic variables.
Cournot's model applied to cellphone service in Colombia, 1995‐2001
Authors: Jhon James Mora R.
Published: October 2006

Purpose

The purpose of this paper is to develop and empirically test the conditions that describe adjustment velocities to reach equilibrium under Cournot's duopoly model.

Design/methodology/approach

The paper uses a vector error correction (VEC) framework as the basis for determining and testing adjustment velocities using data about cellphone service in Colombia in the time period from 1995 to 2001.

Findings

Empirical evidence suggests the following: first of all, companies operating in the cellphone market behave as cournot's competitors and have constant marginal costs; secondly, cellphone companies operating in the eastern zone of Colombia are in long‐term equilibrium; and lastly, equilibrium adjustment velocities are statistically significant. As predicted by theory, in terms of welfare, the existence of equilibrium in Cournot's model implies that cellphone users in the eastern zone of Colombia enjoy a small consumer surplus.

Originality/value

Testing the microeconomic implications of the equilibrium dynamics of Cournot's model, using a VEC framework.
College students, cookies and collections: using holiday study breaks to encourage undergraduate research in special collections
Authors: Summerfield Hammerman Susan , Kern Barbara , Starkey Rebecca , Taylor Anne
Published: October 2006

Purpose

To launch the University of Chicago Library's study break program for undergraduate students which introduces them to rare book and manuscript collections.

Design/methodology/approach

Two study breaks, Love in the Stacks and Things that Go Bump in the Stacks' are described in detail, including selecting material for viewing, marketing the event and basic logistics. In addition the authors discuss the educational materials they created for distribution at the event, attendance, the feedback and comments they received and finally what they learned.

Findings

Provides information about the events, and looks towards future events. Discusses how book and manuscript collections can be intimidating to undergraduate students, who often believe the materials are for the use of faculty or other “serious” scholars.

Originality/value

This paper describes an innovative program that has successfully introduced undergraduate students to Special Collections, and provides information which would allow others to offer a similar program.
Stereoscopic imaging
Authors: Connolly Christine
Published: October 2006

Purpose

To explore the phenomenon of stereoscopic vision and its exploitation in engineering and other professional applications, and in entertainment.

Design/methodology/approach

Starts with a review of how stereo vision works, and the techniques used in 3D movies to present the illusion of depth and movement at right angles to the screen. Looks at some engineering products that build on these techniques, and then at the development of 3D television, based on a different image separation method. Finally looks at developments in stereo machine vision.

Findings

A variety of techniques exist to present left and right views of a scene to the correct eyes and stimulate 3D perception: for example, light‐filtering, alternate‐frame sequencing and optical separation. Fatigue occurs when there is crosstalk between those images, or when the images are presented at too low a frame rate. Many computer modelling software providers produce programs with 3D‐viewing capability for professional engineers. There are some exciting recent developments, such as add‐on PC stereo systems, and 3D TV.

Originality/value

Makes the general scientist aware of the wide range of professional uses of stereo vision, and of the engineering challenges behind 3D film and television.
Labour market inactivity due to family care in Luxembourg
Authors: Valentova Marie
Published: October 2006

Purpose

The purpose of this paper is to deal with an issue of female labour inactivity in the Grand Duchy of Luxembourg, more specifically women in the 16‐65 age category who are long‐term inactive in the formal labour market due to family responsibilities. This group currently represents one‐third of the female population of working age in the country.

Design/methodology/approach

The core of the analysis lies in examining the main socio‐demographic characteristics of family carers. First, the paper provides descriptive analysis of socio‐demographic background of women who are inactive in the labour market. Second it examines the influence of selected socio‐demographic characteristics on the woman's choice not to participate in the labour market due to family care. In the conclusions, based on the outcomes of the conducted analysis and information on the existing welfare setting in the country, the paper suggests policies which should facilitate greater participation of these women in the labour market.

Findings

Referring to the presented theory and to the findings, it can be concluded that Luxembourg is a country with a conservative orientation where women, especially those with lower education, who are married, multiple‐mothers, older than 35 years, Luxembourg nationals, and who are living in households receiving higher social benefits, choose to withdraw from the labour market due to family responsibilities.

Originality/value

Given the lack of more detailed information concerning labour market inactivity of Luxembourgish women and their labour market potential, the fact that the female labour inactivity in the country has never been examined in light of the theory of welfare states’ regimes, and the pressing Lisbon employment strategy targets, this paper represents the first in depth empirical attempt to describe and explain the phenomenon of female labour market inactivity in the Grand Duchy of Luxembourg and provides evidence based policy suggestions which could promote women's labour market participation. The outcomes of the cross‐sectional approach applied in this paper could serve as a base for further more sophisticated analyses of the issue of female inactivity due to family care in Luxembourg. It would be particularly interesting to focus on longitudinal analysis of transistions in and out labour market inactivity and analyze the main socio‐demographic determinants of these transitions.
Predicting the organisational adoption of B2C e‐commerce: an empirical study
Authors: To March L. , Ngai E.W.T.
Published: October 2006

Purpose

Using the literature on innovation research, this paper proposes to establish and empirically test a prediction model which consists of four major factors in the adoption of online retailing by organisations, namely relative advantage, competitive pressure, channel conflict and technical resource competence.

Design/methodology/approach

Data collected from 140 different companies indicate strong empirical support for the model. Relevant hypotheses were derived and tested by logistic regression analysis.

Findings

The results revealed that relative advantage, competitive pressure and technical resource competence have positive effects on the adoption of online retailing.

Research limitations/implications

The research was conducted in Hong Kong, which may limit the generalisability of the findings.

Practical implications

While many studies contribute to an understanding of behaviours of the online market from a consumer perspective, there are few concrete investigations of the organisational viewpoint. With data obtained from practitioners in 140 companies, the major factors of online retailing adoption are addressed, providing strategic directions for managers to evaluate its adoption.

Originality/value

Although many conceptual papers and case studies have identified different potential factors affecting the adoption of online retailing, there are few empirical studies which establish prediction models for its adoption. In fact, during the past decade, in spite of growing interest in B2C transactions, organisations have not necessarily rushed towards adopting online sales. It is critical to have more empirical evidence of the factors affecting the adoption of online sales to help managers further access the benefits of its continuous and potential development. This study attempts to fill the research gap.
Using systems dynamics for human resources management in information systems security
Authors: Trček Denis
Published: October 2006

Purpose

To enable quantitative and qualitative modelling of information systems security management that takes into account technology and human factor.

Design/methodology/approach

The approach is based on systems dynamics and it is done in two phases. In the first phase two basic qualitative models are developed, while in the second phase a possibility to further develop them into quantitative models is studied.

Findings

Appropriate approach to IS security management requires addressing “hard” and “soft” factors. Further, to enable quantitative study of such systems, which are highly non‐linear, exact analytical (mathematically rigorous) treatment is close to impossible. Thus, computer simulations have to be used. One appropriate methodological answer to the above requirements is systems (business) dynamics.

Research limitations/implications

Research limitations are partially related to system dynamics, which operates on an aggregates level. This prevents or makes harder study of phenomena at the micro level, from where the above‐mentioned aggregates emerge. Further, many sub‐areas need further standardisation to enable more realistic simulations – one such case is security policy standardisation and quantification. Similar holds true for threats/vulnerabilities and related taxonomies.

Practical implications

The research presents one of first steps in the direction that could provide quantitative models for effective IS security policy management in organisations.

Originality/value

The research presents two models, one for risk management and the other, which is a generic model that identifies basic variables that have to be addressed for IS security management. Further, findings can be used for security awareness courses.
Innovative influence
Authors: Medvedeva Tatyana A.
Published: October 2006

Purpose

To describe experience of introducing contemporary West management methods in Russian University's management courses and in practice of West‐Siberian rail road management.

Design/methodology/approach

This paper analyzes an experience of innovative influence of a Human Resource Development Center within the Institute of Prospective Transport Technologies and Training of Human Resources, Siberian State University of Transport (Novosibirsk, Russia). Emphasizes the mechanism of innovative influence in time of transitions on the management of organizations through the education of managers.

Findings

Provides information about process of transformation on the micro‐level. Most of the work on transitions has been based on macro‐approach. An organization enables closer contact among people. Example of the applicability the methods available in the West to the situation in Russia. Provides information about how do “mentalities” change.

Research limitations/implications

It is not a general approach to make innovative influence.

Practical implications

A useful example of using technology of participation for making changes in organization with complicated cultural environment.

Originality/value

This paper helps to understand the problems (obstacles) people have in transitional countries and offers practical help on the process of changes.
Intellectics and inventics
Authors: Panaˇ Laura
Published: October 2006

Purpose

The main aim of the paper is to show the necessary convergence of two promising but under‐explored research fields, intellectics and inventics, into a new one, that of intellectual invention, and to discuss new ways of thinking which can be efficient in building an invention culture.

Design/methodology/approach

These purposes are achieved in an interdisciplinary way, in which the various scientific approaches are governed by a philosophical perspective that ensures the conceptual level and the unity of the discourse. The philosophical approach itself is practised in several specific fields and at various levels, being used in order to lay the foundations of a new domain of research. Specific theoretical problems are elucidated through concrete examples furnished by sciences and discussed from the perspective of inventics. Graphical representations help in giving a systemic and integrative perception of complex issues.

Findings

The paper defines in a comprehensive way the two partially studied and till now separately conceived research fields; delimitates and characterizes a new domain of study, of crucial theoretical and practical interest; analyses some types of intellectual techniques involved in all sorts of inventive activity; identifies the main new ways of thinking encouraged by the information technologies and shows their forms and manifestations, as well as the new values promoted by their development. There are proposed some improvements on sociological thinking from the perspective of inventive thinking. The emergence of an invention ethics is anticipated as a necessary component of an invention culture.

Originality/value

Proposes a new field of research, that of the intellectual invention, analyses the main instruments of its study and development, and uses the results of different sciences in order to lay the philosophical foundations of invention ethics as part of the future invention culture.
Marketing of public and private affairs – a link
Authors: Grigorescu Adriana
Published: October 2006

Purpose

To present the public and business systems, their characteristics, structure of link, and to propose tools of improvement.

Design/methodology/approach

It starts with a small survey of the members' opinions, in both systems. First, each environment is analysed as an independent system: business system (BSy) and public administration system (PASy). Second, the role of the marketing of public and private affairs as feedback is investigated. Third, it is presented the conjunction between the two systems and the link between them.

Findings

The marketing behaviour is natural for the BSy and thus its level of marketing knowledge is higher than the poor level of marketing knowledge in PASy. On the other hand PASy is characterized by a lack of marketing attitude about public services.

Research limitation/implication

The proposed tools of improving the link should be tested on groups of public servants and business managers to confirm/infirm the assumption.

Practical implication

A proper marketing for public and private affairs could be the link between them. The link could create and handle the cooperation and cooperation climate in these two environments.

Originality/value

Is the analysis of PASy from the marketing point of view, the conjunction between the two systems and the link through marketing. The paper proposes tools to improve the system by public‐private partnership system.
On index system and mathematical model for evaluation of scientific and technical strength
Authors: Liu Sifeng
Published: October 2006

Purpose

A appraises the scientific and technical strength of a region. In order to make the appraisal scientifically, we need an index system and a evaluation model.

Design/methodology/approach

In this paper, an index system for evaluation of the scientific and technical strength of provincial region has been presented with grey system theory and Delphi Method. A new evaluation model based on trigonal whitenization weight function is formulated. A positive study with evaluation of the scientific and technical strength of Jiangsu Province is conducted.

Findings

It is concluded from the positive study that the scientific and technical strength of Jiangsu Province comes out top in China.

Research limitations/implications

But there are some sticking points that interfere with the scientific and technical strength of Jiangsu Province, such as its shortage of talented person and capital, etc. should be addressed.

Practical implications

It will be helpful to China and other countries.

Originality/value

Application of new evaluation methodology.
Topics in ASC discussion
Authors: Andrew Alex M.
Published: October 2006

Purpose

Selections from topics discussed on the CybCom list over a particularly active period in early 2006 are reviewed. These include the relevance of autopoiesis to sociology, courses of instruction on cybernetics, cybernetics applied to social theory, the “ethical imperative” of von Foerster, and Günther's “polylogic”. Other lists on the internet are also described.

Design/methodology/approach

The aim is to review developments on the internet, especially those of general cybernetic interest.

Findings

The relevance of autopoiesis to sociology is dubious; various courses of instruction exist but cyberneticians should try to enhance visibility; information flows in social systems have useful correspondence to those in living organisms; the “ethical imperative” is not a universal rule; “polylogic” is of interest but not yet embodied in a working computer.

Practical implications

The CybCom list, and others mentioned, are valuable sources of stimulating material.

Originality/value

It is hoped this is a valuable periodic review.
A complex adaptive systems approach to efficiency and innovation
Authors: Tilebein Meike
Published: October 2006

Purpose

The primary objective of this paper is to discuss whether complexity science can help overcome management's dilemma of how to balance efficiency and innovation.

Design/methodology/approach

Complexity science provides an interdisciplinary theoretical approach for studying complex adaptive systems (CAS), which exhibit adequate combinations of both emergent efficiency and emergent innovation. Based on prominent models from complexity science, a generic framework of CAS is proposed that shows the design levers of such systems. This framework then serves to assess recent literature on applications of complexity science to firms. Applications cover a broad range of objectives and four organizational levels: the individual resource, the organizational sub‐unit (SU), the organizational, and the network levels. The generic framework is used to classify the applications' objectives in terms of efficiency and innovation, and to identify the design levers they use.

Findings

CAS offer a valuable theoretical perspective on efficiency and innovation. However, the proposed framework shows that these systems are not utilized to their full potential when applied to firms. Typical applications address either emergent efficiency or emergent innovation and thus fail to balance both.

Research limitations/implications

The paper does not provide an exhaustive literature review on management applications of CAS, but selects exemplary literature.

Originality/value

The paper gives a comprehensive overview of the CAS' perspective in management science. For further research, the proposed generic framework of CAS may serve to analyze, evaluate and integrate applications in order to overcome the efficiency‐innovation dilemma.