bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic field generation in plasmas due to anisotropic laser heating
Authors: Dubroca B. , Tchong M. , Charrier P. , Tikhonchuk V. T. , Morreeuw J.-P.
Published: July 2004

Generation of magnetic fields around the laser speckles in underdense plasma due to an anisotropic laser heating is shown to be an important effect under the conditions previewed for the inertial confinement fusion. The anisotropy of electron distribution persists much longer than the electron collision time and creates a steady source for the quasistationary magnetic field. The structure of magnetic field around the laser beam is studied along with the effects of plasma dynamics, speckle intensity profile, and the electron heat transport.
Scattering of O2 from Al(111)
Authors: Ambaye Hailemariam , Manson J. R. , Weiße Olaf , Wesenberg Claudia , Binetti Marcello , Hasselbrink Eckart
Published: July 2004

Experimental results are presented for the scattering of well-defined beams of molecular oxygen incident on clean Al(111). The data consist of scattered angular distributions measured as a function of incident angle, and for fixed incident angle, the dependence on surface temperature of the angular distributions. The measurements are interpreted in terms of a scattering theory that treats the exchange of energy between the translational and rotational motions of the molecule and the phonons of the surface using classical dynamics. The dependence of the measured angular distributions on incident beam angle and temperature is well explained by the theory. Rotational excitation and quantum excitation of the O2 internal stretching mode are briefly discussed.
Theoretical determination of highly excited states of K2 correlated adiabatically above K(4p)+K(4p)
Authors: Magnier S. , Aubert-Frécon M. , Allouche A. R.
Published: July 2004

The electronic structure of the K2 molecule is revisited to describe the 36 highly excited states dissociating into the three limits K(4s)+K(4f), K(4s)+K(6p), and K(4s)+K(5d), which have not yet been investigated theoretically. Potential energy curves and spectroscopic constants are (re)displayed for the 98 1,3Λg,u(+,−) molecular states correlated adiabatically to the limits up to K(4s)+K(5d). For the 10 states dissociating adiabatically into K(4p)+K(4p) and limits above for which experimental data are available, averaged errors of present results are found to be ΔRe=0.07a0, ΔTe=50 cm−1, Δωe=0.8 cm−1 and ΔDe=60 cm−1. Full energy data are available at the following address http://lasim.univ-lyon1.fr/allouche/k2.html
Experimental and numerical investigation of the vortex formation process behind a heated cylinder
Authors: Ren Maosheng , Rindt Camilo C. M. , van Steenhoven Anton A.
Published: July 2004

This paper describes the three-dimensional (3D) vortex formation process behind a heated cylinder at low Reynolds numbers. Both experimental and numerical techniques are used, including an electrochemical tin-precipitation visualization method, a two-dimensional (2D) high resolution particle velocimetry technique, and a 3D spectral element method. The wake flow is simultaneously investigated in two perpendicular planes using a “dual-plane” configuration. It appears that for Reynolds number around 100 and Richardson number larger than 1.0 thermal plumes occur in the far wake. Correspondingly distinct counterrotating vortices, with a spanwise wavelength of two cylinder diameters, are shown in the near wake. Furthermore, a difference in the flow motion for “in-plume” and “out-of-plume” positions is observed. The vortex shedding process for the “out-of-plume” positions is quite similar to the one for an unheated cylinder, which is a 2D flow. At in-plume positions, it is observed that the flow moves upward from the lower to the upper half of the wake. From the calculated temperature field, a region of unstable thermal stratification in gravity direction is observed at the in-plume positions. This indicates that the upward motion at the in-plume positions is induced by buoyancy when the temperature gradient is large enough.
Fractional diffusion in plasma turbulence
Authors: del-Castillo-Negrete D. , Carreras B. A. , Lynch V. E.
Published: July 2004

Transport of tracer particles is studied in a model of three-dimensional, resistive, pressure-gradient-driven plasma turbulence. It is shown that in this system transport is anomalous and cannot be described in the context of the standard diffusion paradigm. In particular, the probability density function (pdf) of the radial displacements of tracers is strongly non-Gaussian with algebraic decaying tails, and the moments of the tracer displacements exhibit superdiffusive scaling. To model these results we present a transport model with fractional derivatives in space and time. The model incorporates in a unified way nonlocal effects in space (i.e., non-Fickian transport), memory effects (i.e., non-Markovian transport), and non-Gaussian scaling. There is quantitative agreement between the turbulence transport calculations and the fractional diffusion model. In particular, the model reproduces the shape and space-time scaling of the pdf, and the superdiffusive scaling of moments.
Relativistic N-boson systems bound by pair potentials V(rij)=g(rij2)
Authors: Hall Richard L. , Lucha Wolfgang , Schöberl Franz F.
Published: July 2004

We study the lowest energy E of a relativistic system of N identical bosons bound by pair potentials of the form V(rij)=g(rij2) in three spatial dimensions. In natural units ℏ=c=1 the system has the semirelativistic “spinless-Salpeter” Hamiltonian H=∑i=1Nm2+pi2+∑j>i=1Ng(|ri−rj|2), where g is monotone increasing and has convexity g″⩾0. We use “envelope theory” to derive formulas for general lower energy bounds and we use a variational method to find complementary upper bounds valid for all N⩾2. In particular, we determine the energy of the N-body oscillator g(r2)=cr2 with error less than 0.15% for all m⩾0, N⩾2, and c>0.
Microfluidic analog of the four-roll mill
Authors: Hudson S. D. , Phelan F. R. , Handler M. D. , Cabral J. T. , Migler K. B. , Amis E. J.
Published: July 2004

We describe a microfluidic trap, for analysis of fluids and suspensions, that simulates the function of a four-roll mill, a rheological tool with adjustable flow type and rate. These flow characteristics were designed with the assistance of flow simulations and are measured here by micro-particle-image-velocimetry. This miniature device permits microscopic manipulations and measurements (e.g., of cells, particles, and drops) and it is capable of a range of flow types, including simple shear.
Growing vortex patches
Authors: Crowdy Darren , Marshall Jonathan
Published: July 2004

This paper demonstrates that two well-known equilibrium solutions of the Euler equations—the corotating point vortex pair and the Rankine vortex—are connected by a continuous branch of exact solutions. The central idea is to “grow” new vortex patches at two stagnation points that exist in the frame of reference of the corotating point vortex pair. This is done by generalizing a mathematical technique for constructing vortex equilibria first presented by Crowdy [D. G. Crowdy, “A class of exact multipolar vortices,” Phys. Fluids 11, 2556 (1999)]. The solutions exhibit several interesting features, including the merging of two separate vortex patches via the development of touching cusps. Numerical contour dynamics methods are used to verify the mathematical solutions and reveal them to be robust structures. The general issue of how simple vortex equilibria can be continued continuously to more complicated ones with very different vortical topologies is discussed. The solutions are examples of exact solutions of the Euler equations involving multiple interacting vortex patches.
Strain analysis in ultrathin silicide layers in Fe∕CsCl–FeSi57∕Fe sandwiches
Authors: Croonenborghs B. , Almeida F. M. , Cottenier S. , Rots M. , Vantomme A. , Meersschaut J.
Published: July 2004

Epitaxially stabilized iron monosilicide films with the CsCl structure (B2-FeSi) have been investigated by conversion electron Mössbauer spectroscopy and x-ray diffraction. A detailed investigation of the elastic strain in these metastable layers is presented. Using hyperfine interaction information the tetragonal distortion of the silicide lattice could be quantified for layers as thin as 14Å. A general tendency for strain relaxation with increasing layer thickness is observed.
A monolithic diode laser chemical sensor with a quasi-symmetrical sensing waveguide for improved sensitivity
Authors: Wang C. S. , Nolde J. A. , Lofgreen D. D. , Coldren L. A. , Cohen D. A.
Published: July 2004

We demonstrate a diode laser chemical sensor incorporating a self-aligned, symmetrically clad high index contrast evanescent field sensing waveguide. This is accomplished by selectively oxidizing the lower cladding layer of the sensing waveguide. An analyte overlap of 4.8% is obtained with a tightly confined mode, ideal for sensitive affinity assays.
Signatures of quantum transport in self-assembled epitaxialnickel silicide nanowires
Authors: Lin J.-F. , Bird J. P. , He Z. , Bennett P. A. , Smith D. J.
Published: July 2004

We have measured the electrical properties of self-assembled epitaxial NiSi2 nanowires (NWs) formed on Si substrates. We find quantum corrections due to weak antilocalization and electron–electron interactions. Analysis of the magnetoresistance indicates that electron phase coherence in the NWs is limited by Nyquist dephasing below 10K, and by electron–phonon scattering at higher temperatures. The phase-breaking and spin–orbit scattering lengths are found to be ∼45nm and 3–7nm, at 4.2K, respectively, similar to reports for thin NiSi2 films.
Efficient generation of red light by frequency doubling in a periodically-poled nearly-stoichiometric LiTaO3 crystal
Authors: Hu X. P. , Wang X. , He J. L. , Fan Y. X. , Zhu S. N. , Wang H. T. , Zhu Y. Y. , Ming N. B.
Published: July 2004

An efficient generation of red light in a periodically-poled nearly-stoichiometric LiTaO3 (PPSLT) by extracavity single-pass frequency doubling of a diode-pumped, Q-switched Nd:YVO4 laser at 1342nm was realized. An average power of 1.4W of the 671nm red light is obtained at the fundamental power of ∼2.8W with the conversion efficiency of 50%. The high conversion efficiency and steady output of red light indicate that the thick PPSLT is a competitive candidate for frequency conversion in order to construct a compact all-solid-state red laser.
Contiguous stereogenic quaternary carbons: A daunting challenge in natural products synthesis
Authors: Peterson Emily A. , Overman Larry E.
Published: July 2004

One element of structure that invariably increases the difficulty of a chemical synthesis is the presence in the target molecule of contiguous all-carbon quaternary stereocenters. This
Perspective
will examine the most useful transformations and strategies devised recently for directly assembling this structural unit.
Global gene expression analysis identifies molecular pathways distinguishing blastocyst dormancy and activation
Authors: Hamatani Toshio , Daikoku Takiko , Wang Haibin , Matsumoto Hiromichi , Carter Mark G. , Ko Minoru S. H. , Dey Sudhansu K.
Published: July 2004

Delayed implantation (embryonic diapause) occurs when the embryo at the blastocyst stage achieves a state of suspended animation. During this period, blastocyst growth is very slow, with minimal or no cell division. Nearly 100 mammals in seven different orders undergo delayed implantation, but the underlying molecular mechanisms that direct this process remain largely unknown. In mice, ovariectomy before preimplantation ovarian estrogen secretion on day 4 of pregnancy initiates blastocyst dormancy, which normally lasts for 1–2 weeks by continued progesterone treatment, although blastocyst survival decreases with time. An estrogen injection rapidly activates blastocysts and initiates their implantation in the progesterone-primed uterus. Using this model, here we show that among ≈20,000 genes examined, only 229 are differentially expressed between dormant and activated blastocysts. The major functional categories of altered genes include the cell cycle, cell signaling, and energy metabolic pathways, particularly highlighting the importance of heparin-binding epidermal growth factor-like signaling in blastocyst–uterine crosstalk in implantation. The results provide evidence that the two different physiological states of the blastocyst, dormancy and activation, are molecularly distinguishable in a global perspective and underscore the importance of specific molecular pathways in these processes. This study has identified candidate genes that provide a scope for in-depth analysis of their functions and an opportunity for examining their relevance to blastocyst dormancy and activation in numerous other species for which microarray analysis is not available or possible due to very limited availability of blastocysts.
Total synthesis of the marine cyanobacterial cyclodepsipeptide apratoxin A
Authors: Chen Jiehao , Forsyth Craig J.
Published: July 2004

A total synthesis of apratoxin A was developed. Apratoxin A, isolated from
Lyngbya
spp. cyanobacteria, is representative of a growing class of marine cyanobacterial cyclodepsipeptides wherein discrete polypeptide and polyketide domains are merged by ester and amide or amide-derived linkages. In the apratoxins, the N terminus of the peptide domain [(Pro)-(
N
-Me-Ile)-(
N
-Me-ala)-(
O
-Me-Tyr)-(moCys)] is a modified vinylogous cysteine that is joined to a novel ketide [3,7-dihydroxy-2,5,8,8-tetramethylnonanoic acid (Dtna)] by an acid-sensitive thiazoline. The C-terminal proline is esterified to a hindered hydroxyl vicinal to the ketide's
tert
-butyl terminus. Major synthetic challenges included assembly and maintenance the thiazoline-containing moiety and macrolide formation involving acylation of the C39 hydroxyl. The Dtna domain was assembled in the biogenetic direction beginning with a Brown allylation of trimethylacetaldehyde to establish the C39 alcohol configuration. Diastereofacial selective addition of a higher-order dimethylcuprate upon a ring-closing metathesis-derived α,β-unsaturated valerolactone installed the C37 methyl-bearing center. A Paterson anti-aldol process was used to incorporate the remaining two ketide stereogenic centers at C34 and C35. Although attempts to incorporate the thiazoline moiety by condensations of thiol esters bearing α-amino carbamate derivatives failed, an intramolecular Staudinger reduction–aza-Wittig process using α-azido thiol esters was uniquely successful. Late-stage macrocycle closure proceeded well by lactam formation between Pro and
N
-Me-Ile residues, but attempted lactonizations of the Pro carboxylate with the C39 hydroxyl failed. Optimization of C35 hydroxyl group protection-deprotection completed the effort, which culminated in the first total synthesis of apratoxin A and will enable analog generation toward improving differential cytotoxicity.
Alterations in the dynamics of circulating ghrelin, adiponectin, and leptin in human obesity
Authors: Yildiz Bulent O. , Suchard Marc A. , Wong Ma-Li , McCann Samuel M. , Licinio Julio
Published: July 2004

Ghrelin plays a key role in the regulation of growth hormone secretion and energy homeostasis. Adiponectin is exclusively secreted by adipose tissue and is abundantly present in the circulation, with important effects on metabolism. We studied five lean and five obese young men [ages: 24.2 ± 1.0 (lean) and 21.8 ± 1.6 (obese) years (difference not significant); body mass indexes: 35.0 ± 1.3 and 23.0 ± 0.3 kg/m2(P= 0.01)], sampled blood every 7 min over 24 h, and measured ghrelin, adiponectin, and leptin in 2,070 samples for a total of 6,210 data points. Circulating 24-h ghrelin showed significant ultradian fluctuations and an orderly pattern of release in lean and obese subjects with similar pulsatility characteristics. Plasma adiponectin concentrations were significantly lower in the obese group, with lower pulse height. In contrast to leptin, which is secreted in an orderly manner, the 24-h patterns of adiponectin were not significantly different from random in both the lean and obese groups. We show here that adipocytes can simultaneously secrete certain hormones, such as leptin, in patterns that are orderly, whereas other hormones, such as adiponectin, are secreted in patterns that appear to be random. The cross-approximate entropy statistic revealed pattern synchrony among ghrelin–leptin, ghrelin–adiponectin, and leptin–adiponectin hormone time series in the lean and obese subjects. Plasma ghrelin concentrations showed a nocturnal rise that exceeded the meal-associated increases in lean subjects, and this newly identified nocturnal rise was blunted in the obese. We suggest that the blunting of the nocturnal rise of ghrelin is a biological feature of human obesity.
Nutritional Homeostasis in Batch and Steady-State Culture of Yeast
Authors: Saldanha Alok J. , Brauer Matthew J. , Botstein David
Published: July 2004

We studied the physiological response to limitation by diverse nutrients in batch and steady-state (chemostat) cultures of S. cerevisiae. We found that the global pattern of transcription in steady-state cultures in limiting phosphate or sulfate is essentially identical to that of batch cultures growing in the same medium just before the limiting nutrient is completely exhausted. The massive stress response and complete arrest of the cell cycle that occurs when nutrients are fully exhausted in batch cultures is not observed in the chemostat, indicating that the cells in the chemostat are “poor, not starving.” Similar comparisons using leucine or uracil auxotrophs limited on leucine or uracil again showed patterns of gene expression in steady-state closely resembling those of corresponding batch cultures just before they exhaust the nutrient. Although there is also a strong stress response in the auxotrophic batch cultures, cell cycle arrest, if it occurs at all, is much less uniform. Many of the differences among the patterns of gene expression between the four nutrient limitations are interpretable in light of known involvement of the genes in stress responses or in the regulation or execution of particular metabolic pathways appropriate to the limiting nutrient. We conclude that cells adjust their growth rate to nutrient availability and maintain homeostasis in the same way in batch and steady state conditions; cells in steady-state cultures are in a physiological condition normally encountered in batch cultures.
Prediction of phosphorylation sites using SVMs
Authors: Kim Jong Hun , Lee Juyoung , Oh Bermseok , Kimm Kuchan , Koh InSong
Published: July 2004

Motivation: Phosphorylation is involved in diverse signal transduction pathways. By predicting phosphorylation sites and their kinases from primary protein sequences, we can obtain much valuable information that can form the basis for further research. Using support vector machines, we attempted to predict phosphorylation sites and the type of kinase that acts at each site.

Results: Our prediction system was limited to phosphorylation sites catalyzed by four protein kinase families and four protein kinase groups. The accuracy of the predictions ranged from 83 to 95% at the kinase family level, and 76–91% at the kinase group level. The prediction system used—PredPhospho—can be applied to the functional study of proteins, and can help predict the changes in phosphorylation sites caused by amino acid variations at intra- and interspecies levels.

Availability: PredPhospho is available at http://www.ngri.re.kr/proteo/PredPhospho.htm.

Supplementary information:  http://www.ngri.re.kr/proteo/supplementary.doc
Normalization of microarray data using a spatial mixed model analysis which includes splines
Authors: Baird David , Johnstone Peter , Wilson Theresa
Published: July 2004

Motivation: Microarray experiments with thousands of genes on a slide and multiple slides used in any experimental set represent a large body of data with many sources of variation. The identification of such sources of variation within microarray experimental sets is critical for correct deciphering of desired gene expression differences.

Results: We describe new methods for the normalization using spatial mixed models which include splines and analysis of two-colour spotted microarrays for within slide variation and for a series of slides. The model typically explains 45–85% of the variation on a slide with only ∼1% of the total degrees of freedom. The results from our methods compare favourably with those from intensity dependent normalization loess methods where we accounted for twice as much uncontrolled and unwanted variation on the slides. We have also developed an index for each EST that combines the various measures of the differential response into a single value that researchers can use to rapidly assess the genes of interest.

Availability: GenStat code is available from the first author.
Reminiscences and discoveries: The British 3–inch anti–aircraft rocket. Part two: high–flying bombers.
Authors: Kendall D. , Post K.
Published: July 2004

Post told Sandys he had some ideas for using the unrotated projectile at night against high-flying bombers. He was given every encouragement and told to work fast.
Influenza as a model system for studying the cross–species transfer and evolution of the SARS coronavirus
Authors: Bush Robin M.
Published: July 2004

Severe acute respiratory syndrome coronavirus (SARS–CoV) moved into humans from a reservoir species and subsequently caused an epidemic in its new host. We know little about the processes that allowed the cross–species transfer of this previously unknown virus. I discuss what we have learned about the movement of viruses into humans from studies of influenza A, both how it crossed from birds to humans and how it subsequently evolved within the human population. Starting with a brief review of severe acute respiratory syndrome to highlight the kinds of problems we face in learning about this viral disease, I then turn to influenza A, focusing on three topics. First, I present a reanalysis of data used to test the hypothesis that swine served as a ‘mixing vessel’ or intermediate host in the transmission of avian influenza to humans during the 1918 Spanish flu’ pandemic. Second, I review studies of archived viruses from the three recent influenza pandemics. Third, I discuss current limitations in using molecular data to study the evolution of infectious disease. Although influenza A and SARS–CoV differ in many ways, our knowledge of influenza A may provide important clues about what limits or favours cross–species transfers and subsequent epidemics of newly emerging pathogens.
Cell type-specific effects of Rb deletion in the murine retina
Authors: MacPherson David , Sage Julien , Kim Teresa , Ho Dennis , McLaughlin Margaret E. , Jacks Tyler
Published: July 2004

Certain cells of the human retina are extremely sensitive to loss of function of the retinoblastoma tumor suppressor gene RB. Retinoblastomas develop early in life and at high frequency in individuals heterozygous for a germ-line RB mutation, and sporadic retinoblastomas invariably have somatic mutation in the RB gene. In contrast, retinoblastomas do not develop in Rb+/- mice. Although retinoblastoma is thought to have developmental origins, the function of Rb in retinal development has not been fully characterized. Here we studied the role of Rb in normal retinal development and in retinoblastoma using conditional Rb mutations in the mouse. In late embryogenesis, Rb-deficient retinas exhibited ectopic S-phase and high levels of p53-independent apoptosis, particularly in the differentiating retinal ganglion cell layer. During postnatal retinal development, loss of Rb led to more widespread retinal apoptosis, and adults showed loss of photoreceptors and bipolar cells. Conditional Rb mutation in the retina did not result in retinoblastoma formation even in a p53-mutant background. However, on a p107- or p130-deficient background, Rb mutation in the retina caused retinal dysplasia or retinoblastoma.
Widespread Paleopolyploidy in Model Plant Species Inferred from Age Distributions of Duplicate Genes[W]
Authors: Blanc Guillaume , Wolfe Kenneth H.
Published: July 2004

It is often anticipated that many of today's diploid plant species are in fact paleopolyploids. Given that an ancient large-scale duplication will result in an excess of relatively old duplicated genes with similar ages, we analyzed the timing of duplication of pairs of paralogous genes in 14 model plant species. Using EST contigs (unigenes), we identified pairs of paralogous genes in each species and used the level of synonymous nucleotide substitution to estimate the relative ages of gene duplication. For nine of the investigated species (wheat [Triticum aestivum], maize [Zea mays], tetraploid cotton [Gossypium hirsutum], diploid cotton [G. arboretum], tomato [Lycopersicon esculentum], potato [Solanum tuberosum], soybean [Glycine max], barrel medic [Medicago truncatula], and Arabidopsis thaliana), the age distributions of duplicated genes contain peaks corresponding to short evolutionary periods during which large numbers of duplicated genes were accumulated. Large-scale duplications (polyploidy or aneuploidy) are strongly suspected to be the cause of these temporal peaks of gene duplication. However, the unusual age profile of tandem gene duplications in Arabidopsis indicates that other scenarios, such as variation in the rate at which duplicated genes are deleted, must also be considered.
Variation in Expression and Protein Localization of the PIN Family of Auxin Efflux Facilitator Proteins in Flavonoid Mutants with Altered Auxin Transport inArabidopsis thaliana [W]
Authors: Peer Wendy Ann , Bandyopadhyay Anindita , Blakeslee Joshua J. , Makam Srinivas N. , Chen Rujin J. , Masson Patrick H. , Murphy Angus S.
Published: July 2004

Aglycone flavonols are thought to modulate auxin transport in Arabidopsis thaliana via an as yet undefined mechanism. Biochemical studies suggest that flavonoids interact with regulatory proteins rather than directly with the PIN auxin efflux facilitator proteins. Auxin transport is enhanced in the absence of flavonoids (transparent testa4 [tt4]) and reduced in the presence of excess flavonols (tt7 and tt3). Steady state PIN mRNA levels in roots inversely correlate with auxin movement in tt mutants. PIN gene transcription and protein localization in flavonoid-deficient mutants appear to be modulated by developmental cues and are auxin responsive. Modulation of PIN gene expression and protein distribution by localized auxin accumulations occurs in the wild type as well. Flavonoids inhibit auxin transport primarily at the shoot apex and root tip and appear to modulate vesicular cycling of PIN1 at the root tip. In some auxin-accumulating tissues, flavonoid increases and changes in flavonoid speciation are subsequent to auxin accumulation.
Heterogeneous Expression Patterns and Separate Roles of theSEPALLATAGeneLEAFY HULL STERILE1in Grasses[W]
Authors: Malcomber Simon T. , Kellogg Elizabeth A.
Published: July 2004

SEPALLATA (SEP) genes exhibit distinct patterns of expression and function in the grass species rice (Oryza sativa) and maize (Zea mays), suggesting that the role of the genes has changed during the evolution of the family. Here, we examine expression of the SEP-like gene LEAFY HULL STERILE1 (LHS1) in phylogenetically disparate grasses, reconstruct the pattern of gene expression evolution within the family, and then use the expression patterns to test hypotheses of gene function. Our data support a general role for LHS1 in specifying determinacy of the spikelet meristem and also in determining the identity of lemmas and paleas; these two functions are separable, as is the role of the gene in specifying floret meristems. We find no evidence that LHS1 determines flower number; it is strongly expressed in all spikelet meristems even as they are producing flowers, and expression is not correlated with eventual flower number. LHS1 expression in only the upper flowers of the spikelet appears to be the ancestral state; expression in all flowers is derived in subfamily Pooideae. LHS1 expression in pistils, stamens, and lodicules varies among the cereals. We hypothesize that LHS1 may have affected morphological diversification of grass inflorescences by mediating the expression of different floral identity genes in different regions of the floret and spikelet.
Overexpression ofGLUTAMINE DUMPER1Leads to Hypersecretion of Glutamine from Hydathodes of Arabidopsis Leaves[W]
Authors: Pilot Guillaume , Stransky Harald , Bushey Dean F. , Pratelli Reéjane , Ludewig Uwe , Wingate Vincent P.M. , Frommer Wolf B.
Published: July 2004

Secretion is a fundamental process providing plants with the means for disposal of solutes, improvement of nutrient acquisition, and attraction of other organisms. Specific secretory organs, such as nectaries, hydathodes, and trichomes, use a combination of secretory and retrieval mechanisms, which are poorly understood at present. To study the mechanisms involved, an Arabidopsis thaliana activation tagged mutant, glutamine dumper1 (gdu1), was identified that accumulates salt crystals at the hydathodes. Chemical analysis demonstrated that, in contrast with the amino acid mixture normally present in guttation droplets, the crystals mainly contain Gln. GDU1 was cloned and found to encode a novel 17-kD protein containing a single putative transmembrane span. GDU1 is expressed in the vascular tissues and in hydathodes. Gln content is specifically increased in xylem sap and leaf apoplasm, whereas the content of several amino acids is increased in leaves and phloem sap. Selective secretion of Gln by the leaves may be explained by an enhanced release of this amino acid from cells. GDU1 study may help to shed light on the secretory mechanisms for amino acids in plants.
Endoplasmic Reticulum Export Sites and Golgi Bodies Behave as Single Mobile Secretory Units in Plant Cells[W]
Authors: daSilva Luis L.P. , Snapp Erik L. , Denecke Jürgen , Lippincott-Schwartz Jennifer , Hawes Chris , Brandizzi Federica
Published: July 2004

In contrast with animals, plant cells contain multiple mobile Golgi stacks distributed over the entire cytoplasm. However, the distribution and dynamics of protein export sites on the plant endoplasmic reticulum (ER) surface have yet to be characterized. A widely accepted model for ER-to-Golgi transport is based on the sequential action of COPII and COPI coat complexes. The COPII complex assembles by the ordered recruitment of cytosolic components on the ER membrane. Here, we have visualized two early components of the COPII machinery, the small GTPase Sar1p and its GTP exchanging factor Sec12p in live tobacco (Nicotiana tabacum) leaf epidermal cells. By in vivo confocal laser scanning microscopy and fluorescence recovery after photobleaching experiments, we show that Sar1p cycles on mobile punctate structures that track with the Golgi bodies in close proximity but contain regions that are physically separated from the Golgi bodies. By contrast, Sec12p is uniformly distributed along the ER network and does not accumulate in these structures, consistent with the fact that Sec12p does not become part of a COPII vesicle. We propose that punctate accumulation of Sar1p represents ER export sites (ERES). The sites may represent a combination of Sar1p-coated ER membranes, nascent COPII membranes, and COPII vectors in transit, which have yet to lose their coats. ERES can be induced by overproducing Golgi membrane proteins but not soluble bulk-flow cargos. Few punctate Sar1p loci were observed that are independent of Golgi bodies, and these may be nascent ERES. The vast majority of ERES form secretory units that move along the surface of the ER together with the Golgi bodies, but movement does not influence the rate of cargo transport between these two organelles. Moreover, we could demonstrate using the drug brefeldin A that formation of ERES is strictly dependent on a functional retrograde transport route from the Golgi apparatus.
Overeducation and human capital endowments
Authors: Bu¨chel Felix , Pollmann‐Schult Matthias
Published: July 2004

Tests the hypothesis that overeducation is contingent upon the differing human capital endowments of employees. The analyses are based on data from the German Life History Study (GLHS). Applies a trivariate probit model which takes into account the selective acquisition of school qualifications, and the selective choice of vocational training programs with varying levels of quality. The findings confirm that the type of school diploma obtained has a strong effect on the later risk of overeducation. Furthermore, in the case of the intermediate school diploma – the qualification typically held by those entering initial vocational training in Germany – the grade attained also proves to have a strong effect on the risk of overeducation. In line with the existing literature, this paper finds that the risk of overeducation decreases as traditional human capital endowments such as experience, tenure, and on‐the‐job‐training increase.
Satisfaction with business‐to‐employee benefit systems and organizational citizenship behavior
Authors: Huang Jen‐Hung , Jin Bih‐Huang , Yang Chyan
Published: July 2004

Marketing the products of other companies within an individual company intranet can benefit both employees and the company itself. This study examines the dimensions of satisfaction with a business‐to‐employees (B2E) benefit system and the linkages between satisfaction and organizational citizenship behavior (OCB). Structural equation modeling of data shows that convenience, delivery, interface, accuracy, price and security are factors that affect employee satisfaction with the B2E benefit system. Price is more important to the satisfaction of males than females. Significant, positive relationships were found between satisfaction and OCB. Perceived organizational support plays a stronger mediating role in leading to OCB for females than it does for males.
Identifying export opportunities: the case of Thailand
Authors: Cuyvers Ludo
Published: July 2004

A decision support model is presented and discussed which aims at identifying realistic export opportunities for a given exporting country. The model consists of a screening process of four consecutive filters, through which relevant information on markets (such as country risk indicators, macroeconomic data, imports per product group, etc.) is fed, and which allows the identification and deletion of less interesting market opportunities. Results are reported of the application of this decision support model to the case of Thailand, adapted for an analysis of foreign trade data at the SITC four‐digit level up to 1997. These results are compared with previous results obtained using the same model. In this way, Thailand's export opportunities in individual countries, and in the Asia‐Pacific region in particular, are listed and categorised according to criteria such as import market characteristics and Thailand's market share in the various markets.
China's entry to WTO: global marketing issues, impact, and implications for China
Authors: Agarwal James , Wu Terry
Published: July 2004

The transition from a command economy to a market‐based economy has been remarkably successful in China. After 15 years of negotiations, China finally joined the World Trade Organization (WTO) in December 2001. Because of trade and investment liberalization under the WTO, there will be greater competition between Chinese and foreign firms, both inside China and outside China. While there is a great deal of economic literature on China's entry to the WTO, there has been no research on the global marketing impact and implications of China's membership of the WTO. This paper is an attempt to fill this gap. The objective of this study is to examine the general impact of China's entry to the WTO and to assess the global marketing implications of specific trade‐related policy issues within the WTO framework for China. Eleven specific WTO policy issues are examined and several global marketing propositions offered in terms of the WTO's impact on and implications for China.
Marketing and e‐commerce as tools of development in the Asia‐Pacific region: a dual path
Authors: Wood Charles M.
Published: July 2004

International development agencies claim that commercial applications of information and communication technology (ICT) have great potential to accelerate economic growth in developing nations. This paper investigates this idea and proposes that the Internet expands the potential of marketing activities to help developing countries pursue development goals along a dual path, one that includes activities that are “top‐down” in nature (e.g. infrastructure development), and another that involves “bottom‐up” activities (e.g. entrepreneurship). Both paths involve the expansion of marketing efforts and represent significant opportunities for business development and investment. Attention is given to the Asia‐Pacific region and to the processes and outcomes of development springing from bottom‐up or “grassroots” approaches, and how enhanced marketing activities can help nations reach key development goals. Finally, an interdisciplinary conceptual model is advanced regarding how a blend of top‐down and bottom‐up approaches may be used to encourage the diffusion of online marketing activities and to help foster economic and social development in the emerging economies in the Asia‐Pacific region.
Bank choice behavior of small and medium‐sized construction firms
Authors: Yavas Ugur , Babakus Emin , Eroglu Sevgin
Published: July 2004

A model of bank choice behavior for small and medium‐sized firms in the construction industry is developed and tested. The results suggest that bank choice behavior of homebuilders can be represented as a global construct with three viable components: search, credence and experience. The model allows for a comprehensive examination of the relationships between commercial banks and homebuilders. Implications for bank managers are discussed.
Barriers and benefits in the adoption of e‐government
Authors: Gilbert David , Balestrini Pierre , Littleboy Darren
Published: July 2004

This article examines the reasons individuals would choose electronic self‐service delivery methods over more traditional methods of service delivery for government services. The study investigated the factors related to decision making when people consider and evaluate the usage of an online e‐government delivery mechanism. The approach taken was based on a combination of attitudinal technology adoption models and the service quality concept, with data gathered via a questionnaire. Trust, financial security, information quality (all adoption barriers), time and money (both adoption benefits) were found to predict potential usage. That is willingness to use the online delivery option will be present if organisations can develop trust relationships with individuals, assure them that their financial details are secure, provide information that is relevant, accurate and up‐to‐date, and save individuals time and money. The results are significant to the public service manager who needs to consider both the barriers to adoption and the benefits of adoption if they are to develop plans to increase the take‐up of their electronic services.
Authority, acceptance, ability and performance‐based budgeting reforms
Authors: Andrews Matthew
Published: July 2004

Performance‐based budgeting (PBB) is a prominent reform around the world, and has been in prominence in the USA for over a decade now. Evidence presented in this article suggests, however, that the reform is commonly implemented in a limited fashion. This raises the questions, “Why do few states adopt PBB meaningfully?” and “What needs to be done to ensure meaningful adoption?”. In addressing these questions with reference to case studies of state performance‐based budgeting, this article suggests that a three‐factor model is useful in thinking about PBB implementation. In this model authority, acceptance and ability intersect to determine the “reform space” a government has for PBB. In most governments this reform space seems rather constrained.
Public sector accountability failure in an emerging economy
Authors: Lodhia Sumit K. , Burritt Roger L.
Published: July 2004

Adoption of new public sector management (NPM) is commonplace in both developed and emerging economies. One premise of NPM is that an effective accountability mechanism is in place. It is argued here that where bad management and corruption are present, this fundamental accountability mechanism may fail for two reasons. These are considered further through the situation existing in Fiji in relation to problems experienced at the National Bank of Fiji (NBF). The demise of the NBF provides an example of a country where NPM has been introduced, where poor management and corruption are entrenched and where accountability has not worked because parties do not provide a proper account of their actions. This scandal illustrates the need for proponents of NPM to consider the context into which the system is being fitted, such as poor management, the extent of corruption and presence of political favours, when considering the net benefits likely to arise from its introduction.
Germany and the United States
Authors: Maidment Fred
Published: July 2004

Germany and the USA have had a very close relationship over the past 50 years, due to their mutual interests in defense against the Soviet Union and that country's allies. Today, due to the end of the Cold War, that threat is gone and the need for the US commitment to defend Germany no longer exists. In addition, German society and economy are both going in very different directions from the USA, with important demographic changes leading to very different economic futures for both countries. This article explores the social, political and economic consequences and ramifications of these changes in the relationship between the USA and Germany.
Information and communications technology training for British librarians
Authors: Monk Des
Published: July 2004

This paper considers the difficulties involved in training a group of UK public library workers up to the level of computer literacy associated with the European Computer Driving Licence (ECDL). The policy context for this study is provided by the need for ICT (information and communications technology) training that was recognised by the Library Information Commission (LIC) reports of 1997 and 1998. It was decided to investigate the efficiency of this £20 million training programme by means of a longitudinal study conducted over four years, starting in 1999, that followed a group of 20 librarians working in the north‐west of England. To further illuminate the results, a similar cohort of librarians was tracked in east Finland, over the same time period. The results suggest that the LIC's aim of getting all library staff up to the ECDL has not been realised. Furthermore, there has been a significant difference in terms of training between professional and front‐line staff. At the end of the paper, some suggestions are made that might enhance the efficacy of such training programmes, especially in terms of financial incentives.
The BBC Written Archives
Authors: Kavanagh Jacqueline
Published: July 2004

Presents an history of the Written Archives at the British Broadcasting Corporation (BBC), stating that the Written Archives constitute the working papers of the Corporation from 1922 to the 1980s. Looks at present developments and how this will be managed into the twenty‐first century.
Management use of records in Delta State University, Abraka, Nigeria
Authors: Osahon Uwaifo Stephen
Published: July 2004

The paper takes a look at Management use of Records in Delta State University, Abraka, Nigeria. The importance of records and records management programmes was given. Other issues that were investigated include: the components of records management in operation, maintenance and use of records, storage and security of records for effective use, records disposition schedule, and the strength and qualification of the records management personnel. The paper concludes that the management staff of Delta State University, Abraka, see records as indispensable tools in planning, decision making and implementation. Over the years, the authorities of the University have therefore created, maintained and used numerous records. Certain problems which hamper the effective use of records by management in the University were identified as: lack of clear‐cut records management standard, inadequate professional records management personnel, non‐availability of automatic security/protection system and erratic electric power supply. In order to eradicate or overcome these setbacks, the researcher has made some far‐reaching recommendations.
Branch employees’ perceptions towards implications of e‐banking in Greece
Authors: Lymperopoulos Constantine , Chaniotakis Ioannis E.
Published: July 2004

This paper aims to identify the potential effects of e‐banking through literature and surveys the Greek branch employees’ perceptions towards them. According to the relevant literature review the 14 main implications of e‐banking adoption were identified. Based on these findings, a questionnaire was designed and completed by 527 branch employees. Data factor analysis revealed the existence of four distinct factors which were named banks’ “hard advantages”, “soft advantages”, “market effects”, and “risk”, whereas further analysis provided evidence of the relationship that exists among the perceptions, the personal characteristics of the respondents and the organisational characteristics of their banks.
Fast moving luxury goods: positioning strategies for Scotch whisky in Thai department stores
Authors: Mandhachitara Rujirutana , Lockshin Larry
Published: July 2004

This paper examines the Scotch whisky market in Thai department stores over a two‐year period and shows their importance to Thai retailing. The paper then finds that the category behaves as both a fast moving consumer goods market and as a luxury market. Product movement is rapid when compared to other luxury good categories and there is some evidence of discounting. The data, derived from a sample of weekly sales through 25 department stores over two years, show differences in distribution, merchandising, and pricing strategy across different chains. The paper concludes by looking at the potential causes of profit differences across these chains.
Supply chain logistics risks
Authors: Cavinato Joseph L.
Published: July 2004

Risks and uncertainties are ever more noted and factored into decision making today, and those stemming from supply chains are prominent in the competitiveness and viability of companies and organizations. The idea that every supply chain is made up of five internal chain/network constructs is presented, and these are physical, financial, informational, relational, and innovational. Further, four categorizations of relevant product/supply costs are presented as are four types of supply risks.
An analysis of supply risk assessment techniques
Authors: Zsidisin George A. , Ellram Lisa M. , Carter Joseph R. , Cavinato Joseph L.
Published: July 2004

Purchasing organizations are exposed to risk in their interactions with suppliers, whether it is recognized and managed, addressed in a cursory manner, or altogether ignored. In order to understand the supply risk that exists, purchasing organizations can proactively assess the probability and impact of supply risk in advance, or reactively discover risk after a detrimental event occurs. The purpose of this study is to explore, analyze, and derive common themes on supply risk assessment techniques. Findings from this research indicate that purchasing organizations can assess supply risk with techniques that focus on addressing supplier quality issues, improving supplier processes, and reducing the likelihood of supply disruptions. From an agency theory perspective, these risk assessment techniques facilitate the obtaining of information by purchasing organizations to verify supplier behaviors, promoting goal congruence between buying and selling firms, and reducing outcome uncertainty associated with inbound supply.