bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence for involvement of α1D‐adrenoceptors in contraction of femoral resistance arteries using knockout mice
Authors: Zacharia Joseph , Hillier Chris , Tanoue Akito , Tsujimoto Gozoh , Daly Craig J , McGrath John C , MacDonald Allan
Published: September 2005

The role of α1D‐adrenoceptors in vasoconstrictor responses to noradrenaline in mouse femoral resistance arteries was investigated using wire myography in α1D‐adrenoceptor knockout (α1D‐KO) and wild‐type (WT) mice of the same genetic background.

α1D‐KO mice were 2.5‐fold less sensitive than WTs to exogenous noradrenaline and BMY 7378 was significantly less potent against noradrenaline in α1D‐KO mice than in WTs, showing a minor contribution of α1D‐adrenoceptors in response to noradrenaline.

Prazosin and 5‐methyl‐urapidil were equally effective against noradrenaline in α1D‐KO and WT mice. Chloroethylclonidine produced a significantly greater attenuation of the response to noradrenaline in α1D‐KO mice than in WTs.

Responses to electrical field stimulation (EFS), at 2–20 Hz for 10 s and 0.09 ms pulse width were significantly smaller overall in α1D‐KOs than in WTs although no significant differences were seen at the different frequencies.

BMY 7378 produced significantly greater inhibition of responses at 2 and 5 Hz than at higher frequencies in WTs. In α1D‐KOs, this greater sensitivity to BMY 7378 at lower frequencies was not apparent, confirming that the effect of BMY 7378 was due to blockade of α1D‐adrenoceptors.

Prazosin and 5‐methyl‐urapidil had similar inhibitory effects on responses to EFS in α1D‐KO and WT mice. Chloroethylclonidine inhibited responses to EFS to a significantly greater extent in α1D‐KO mice.

The present study with α1D‐KO mice shows that α1D‐adrenoceptors contribute to vasoconstrictor responses to exogenous and neurally released noradrenaline in femoral resistance arteries.

British Journal of Pharmacology (2005) 146, 942–951. doi:10.1038/sj.bjp.0706395
Leukocyte differentiation antigens in canine cutaneous and oral plasmacytomas
Authors: SCHRENZEL MARK D. , NAYDAN DIANE K. , MOORE PETER F.
Published: September 2005

Seventeen cutaneous and oral tumours with light microscopic features of plasmacytomas from 16 dogs were studied. Clinically, most neoplasms were benign, although three recurred after excision and three were locally invasive. Tumours most often arose on the pinnae, digits, gingiva, and inguinal regions near areas of chronic inflammation and exhibited variable degrees of plasmacytic differentiation microscopically. Diagnosis of plasmacytoma was confirmed in paraffin‐embedded tissues with a panel of leukocyte differentiation antigen markers that included cross‐reactive antibodies for Mb‐1 (CD79a), CD3, and vimentin and canine‐specific antibodies for CD45RA and CD18. Immunoreactivity for Mb‐1 and CD45RA, including staining of multinucleate cells and cells with karyomegaly, confirmed a B‐cell origin of neoplasms, while staining for CD3 and CD18 revealed an extensive network of infiltrative T‐cells and dendritic cells in tumours suggestive of a directed immune response. These findings (i) demonstrate the value of using a panel of antibodies for leukocyte antigens to differentiate plasmacytomas from other cutaneous and oral round cell tumours, and (ii) suggest that immune recognition and responsiveness within tumours may play a role in the behaviour of plasmacytomas in dogs by affecting tumour cell growth and differentiation.
Composition fluctuations in a homopolymer-diblock copolymer mixture covering the three-dimensional Ising, isotropic Lifshitz, and Brasovskiĭ classes of critical universality
Authors: Pipich Vitaliy , Schwahn Dietmar , Willner Lutz
Published: September 2005

The phase behavior of a three-component polymer blend consisting of a critical mixture of polybutadiene and polystyrene (PB/PS) with varying amount of a symmetric PB-PS diblock copolymer was explored with small-angle neutron scattering. Our focus were thermal composition fluctuations which we discuss in terms of mean field, three-dimensional Ising, isotropic Lifshitz, and Brasovskiĭ classes of critical universality. Particular attention is spent to the observation of a narrow reentrant two-phase regime and double critical point in the Lifshitz critical regime as well as the Lifshitz line. Critical exponents of the isotropic Lifshitz case are proposed in spite of the demonstrated nonexistence of the isotropic Lifshitz critical point. The Ginzburg number (Gi) and Flory-Huggins parameter were determined over the whole diblock concentration range; Gi changes by three orders of magnitude, two orders of magnitude of that change over a 0.03 diblock concentration interval within the isotropic Lifshitz regime.
A novel quantum mechanical/molecular mechanical approach to the free energy calculation for isomerization of glycine in aqueous solution
Authors: Takahashi Hideaki , Kawashima Yuko , Nitta Tomoshige , Matubayasi Nobuyuki
Published: September 2005

The free energy change associated with the isomerization reaction of glycine in water solution has been studied by a hybrid quantum mechanical/molecular mechanical (QM/MM) approach combined with the theory of energy representation (QM/MM-ER) recently developed. The solvation free energies for both neutral and zwitterionic form of glycine have been determined by means of the QM/MM-ER simulation. The contributions of the electronic polarization and the fluctuation of the QM solute to the solvation free energy have been investigated. It has been found that the contribution of the density fluctuation of the zwitterionic solute is estimated as −4.2kcal∕mol in the total solvation free energy of −46.1kcal∕mol, while that of the neutral form is computed as −3.0kcal∕mol in the solvation free energy of −15.6kcal∕mol. The resultant free energy change associated with the isomerization of glycine in water has been obtained as −7.8kcal∕mol, in excellent agreement with the experimental data of −7.3 or −7.7kcal∕mol, implying the accuracy of the QM/MM-ER approach. The results have also been compared with those computed by other methodologies such as the polarizable continuum model and the classical molecular simulation. The efficiency and advantage of the QM/MM-ER method has been discussed.
Incorporating a hydrophobic solid into a coarse grain liquid framework: Graphite in an aqueous amphiphilic environment
Authors: Nielsen Steven O. , Srinivas Goundla , Klein Michael L.
Published: September 2005

A method is presented for incorporating a solid into a coarse grain liquid model. From the fully atomistic solid-liquid site-site description the solid is replaced by an implicit potential. The liquid particles are then coarse grained by appealing to statistical mechanics and probability theory. The dimensionality problem which arises is overcome with an approximate treatment and a force field is derived for graphite interacting with an existing coarse grain liquid model. Water is considered separately by using the experimentally observed contact angle between a water droplet and a graphite surface. Finally, the solid is restored to an explicit representation to allow for different geometries.
Compensation of shadow effect for one-dimensional diffractive structures via an approach of microfabrication
Authors: Fu Yongqi , Bryan Ngoi Kok Ann , Butler David Lee
Published: September 2005

A compensation method is introduced from the microfabrication perspective for the purpose of degrading the shadow effect of diffractive structures. A dead blaze area ε that is generated during the fabrication process makes a great contribution to the shadow effect. Our experiments have demonstrated that it can be reduced by tilting the work stage to a certain angle during the direct writing of the focused ion beam (FIB). The redeposition effect, round effect, and discrimination error of the FIB affect the compensation of the shadow effect and cause the dead blaze area to still exist more or less after the compensation when the stage–tilting angle is less than 50°. The compensation can be further improved with the aid of chemical gas assistant etching. In addition, two important factors relevant to the compensation, characterization errors from atomic force microscopy and optical interferometry, and limitation of depth of focus, are discussed in detail.
The damping of plasma waves
Authors: Drummond W. E.
Published: September 2005

The damping of plasma waves is considered for both large and small amplitudes. Both reversible and irreversible energy exchanges between the particles and the field during the initial transient are discussed, and a physical picture of these processes is given. The late time decay of large amplitude waves is explicitly given along with a physical picture.
Effect of partial charge parametrization on the fluid phase behavior of hydrogen sulfide
Authors: Kamath Ganesh , Lubna Nusrat , Potoff Jeffrey J.
Published: September 2005

The effect of partial charge parametrization on the fluid phase behavior of hydrogen sulfide is investigated with grand canonical histogram reweighting Monte Carlo simulations. Four potential models, based on a Lennard-Jones + point charge functional form, are developed. It is shown that Lennard-Jones parameters can be tuned such that partial charges for the sulfur atom in the range −0.40<qS<−0.252 will lead to an accurate reproduction of experimental vapor-liquid equilibria. Each of the parameter sets developed in this work are used to predict the pressure composition behavior H2S-n-pentane at 377.6 K. While the mixture calculation provides a means of reducing the number of candidate parameter sets, multiple parameter sets were found to yield an excellent reproduction of both the pure component and mixture phase behavior.
Numerical simulation and visualization of stochastic and ordered electron motion forced by electrostatic waves in a magnetized plasma
Authors: Dieckmann M. E. , Shukla P. K. , Parviainen M. , Ynnerman A.
Published: September 2005

The interaction of electrons with strong electrostatic waves and an external magnetic field, which is oriented obliquely to the wave vector, leads to stochastic acceleration and acceleration by the cross-field transport of trapped electrons. This wave-particle interaction involves three velocity components of the electrons and, for a plane wave, one spatial position. The phase-space evolution is also affected by nonlinear oscillations in the amplitude of the saturated wave, and the system becomes explicitly time dependent. Here, the wave-particle interactions are investigated with a particle-in-cell simulation, and the results are visualized by examining orbits of individual electrons and also time-evolving phase-space structures. Two clearly distinct electron populations are identified, one due to cross-field transport and the other due to stochastic interactions, which are robust against growing secondary modes.
On the lack of thermal percolation in carbon nanotube composites
Authors: Shenogina N. , Shenogin S. , Xue L. , Keblinski P.
Published: September 2005

Recent experiments demonstrated very low percolation thresholds for carbon nanotube composites signified by steep increases in electrical conductivity at very low nanotube loadings. By contrast, thermal transport measurements, even on the same samples, showed no signature of the percolation threshold. These contrasting behaviors are particularly intriguing considering that both transport processes are described by the same continuum equation. In this letter we present a theoretical analysis based on finite element calculations that expose the underlying reasons for markedly different behaviors of electrical and thermal transport in high aspect ratio fiber composites.
By-emitter degradation analysis of high-power laser bars
Authors: Bull S. , Tomm J. W. , Oudart M. , Nagle J. , Scholz C. , Boucke K. , Harrison I. , Larkins E. C.
Published: September 2005

The study of degradation process in high-power laser diodes, in particular, high-power laser bars, has become increasingly important as the output power of these devices continues to rise. We present a “by-emitter” degradation analysis technique, which examines degradation processes at both the bar and emitter levels. This technique focuses on understanding the dynamic mechanisms by which packaging-induced strain and operating conditions lead to the formation of defects and subsequent emitter and bar degradations. In the example presented, we examine a highly compressively strained bar, where thermally induced current runaway is found to be an important factor in the bar degradation and eventual device failure.
Focusing properties of a rectangular-rod photonic-crystal slab
Authors: Feng Shuai , Li Zhi-Yuan , Feng Zhi-Fang , Ren Kun , Cheng Bing-Ying , Zhang Dao-Zhong
Published: September 2005

The focusing properties of a photonic-crystal (PC) slab consisting of a square lattice of rectangular dielectric rods in the air background are studied theoretically. We employ the finite-difference time-domain method to investigate the field patterns of a point source placed in the vicinity of the PC slab and find that an image can form in the opposite side of the slab in a frequency window located slightly below the fundamental band gap. We change the orientation of the rectangular rods and find that when the rods are arranged asymmetrically with respect to the surface normal of the slab, the image spot can show a vertical shift relative to the point source. The influence of the PC slab thickness on the quality of the image is also analyzed. From these simulation results and the equifrequency-surface contour analysis, we find that the dominant physical mechanism that shapes the focusing behavior of these rectangular-rod PC slabs in the ground photonic band is the self-collimation effect instead of the negative refraction effect.
Low noise and stable emission from carbon nanotube electron sources
Authors: de Jonge Niels , Allioux Myriam , Oostveen Jim T. , Teo Kenneth B. K. , Milne William I.
Published: September 2005

Remarkably stable and low noise field-emission electron sources have been obtained using individual carbon nanotubes. The maximum current fluctuation observed over 1h was merely 0.5% and the emission frequency spectrum exhibited 1∕f behavior over a bandwidth of 0.1–25Hz, above which the shot-noise limit was reached. The average noise percentage was determined to be 0.08% (i.e., a signal-to-noise ratio of 1250) for seven CNT emitters operated at several current levels. The influence of the vacuum level was also investigated.
In situ infrared spectroscopy of hafnium oxide growth on hydrogen-terminated silicon surfaces by atomic layer deposition
Authors: Ho M.-T. , Wang Y. , Brewer R. T. , Wielunski L. S. , Chabal Y. J. , Moumen N. , Boleslawski M.
Published: September 2005

The interface formation between HfO2 and H-terminated Si(111) and Si(100) is studied by in situ infrared absorption spectroscopy during atomic layer deposition using alternating tetrakis-ethylmethylamino hafnium (TEMAH) and deuterium oxide (D2O) pulses. The HfO2 growth is initiated by the reaction of TEMAH with Si–H rather than D2O, and there is no evidence for SiO2 formation at moderate growth temperatures (∼100°C). Although Rutherford backscattering shows a linear increase of Hf coverage, direct observations of Si–H, Si–O–Hf, and HfO2 phonons indicate that five cycles are needed to reach the steady state interface composition of ∼50% reacted sites. The formation of interfacial SiO2 (∼0.7nm) is observed after postdeposition annealing at 700°C in ultrapure nitrogen.
Epitaxial nanostructure and defects effective for pinning in Y(RE)Ba2Cu3O7−x coated conductors
Authors: Yamada Y. , Takahashi K. , Kobayashi H. , Konishi M. , Watanabe T. , Ibi A. , Muroga T. , Miyata S. , Kato T. , Hirayama T. , Shiohara Y.
Published: September 2005

This paper describes the microstructure to improve the magnetic field dependence of the critical current density, Jc, of Y(RE)Ba2Cu3O7−x [Y(RE)123, RE: Gd and Sm] coated conductors. A columnar microstructure 10nm in diameter has been obtained by using Y123 targets including yttrium-stabilized zirconium for the pulsed-laser deposition. This columnar structure, composed of BaZrO3 and Y123, continued from the substrate to the surface of the film 0.25μm in thickness. We have named it “the bamboo structure” from its morphology. The bamboo structure was effective for increasing Jc in a magnetic field especially parallel to the c-axis. We have also found stacking faults in RE123 effective to improve Jc.
Electrochemical hydrogen storage of Ti–V-based body-centered-cubic phase alloy surface-modified with AB5 nanoparticles
Authors: Yu X. B. , Walker G. S. , Grant D. M. , Wu Z. , Xia B. J. , Shen J.
Published: September 2005

A composite of Ti–V-based bcc phase alloy surface-modified with AB5 nanoparticles was prepared by ball milling. The composite showed significantly improved electrochemical hydrogen release capacities. For example, the 30 min ball milled Ti–30V–15Mn–15Cr+10wt%AB5 showed a discharge capacity in the first cycle, at 353 K, of 886mAhg−1, corresponding to 3.38 wt % of hydrogen, with a 45mAg−1 discharge current. It is thought that this high capacity is due to the enhanced electrochemical-catalytic activity from the alloy surface covered with AB5 nanoparticles, which not only have better charge-discharge capacity themselves, acting as both an electrocatalyst and a microcurrent collector, but also result in the greatly enhanced hydrogen atomic diffusivities in the nanocrystalline relative to their conventional coarse-grained counterparts. These results provide new insight for use of Ti–V-based bcc phase alloy for high-energy batteries.
Observation of the quantum-confinement effect in individual Ge nanocrystals on oxidized Si substrates using scanning tunneling spectroscopy
Authors: Nakamura Yoshiaki , Watanabe Kentaro , Fukuzawa Yo , Ichikawa Masakazu
Published: September 2005

Scanning tunneling spectroscopic studies revealed the quantum-confinement effects in Ge nanocrystals formed with ultrahigh density (>1012cm−2) by Ge deposition on ultrathin Si oxide films. With decreasing crystal size, the conduction band maximum upshifted and the valence band minimum downshifted. The energy shift in both cases was about 0.7 eV with the size change from 7 to 2 nm. This shows that the energy band gaps of Ge nanocrystals increased to ∼1.4eV with decreasing size. This size dependence can be explained by the quantum-confinement effect in Ge nanocrystals.
Current Understanding of Formation Mechanisms in Surfactant-Templated Materials
Authors: Edler Karen J.
Published: September 2005

Surfactant-templated materials are created through self-assembly in solutions containing both surfactant micelles and an inorganic species. The resulting materials are composites containing an organized surfactant micelle array encapsulated in the inorganic material. Removal of the surfactants generates nanoscale pores which replicate the highly organized micelle phase, producing high surface area materials with uniform pores that have applications in catalysis, molecular separation, encapsulation for sensors and slow release, and thin films for optoelectronics and photoelectrochemical devices. This review looks at recent work aimed at understanding how these materials self-assemble from dilute surfactant solutions to form intricate nanoscale configurations, which also often show complex and highly ordered structures on longer length scales.
Hydrolysable carbohydrate in tropical soils under adjacent forest and savanna vegetation in Lamto, Côte d'Ivoire
Authors: Nacro Hassan Bismarck , Larré-Larrouy Marie Christine , Feller Christian , Abbadie Luc
Published: September 2005

Carbohydrates represent 5–25% of the organic matter in soils. They constrain microbial activities and mineral nutrient production in soil and also reflect the whole microorganism community dynamic. The objective of this study was to determine the contents and composition of hydrolysable carbohydrates in soils collected in a forest–savanna mosaic landscape in the region of Lamto (Côte d’Ivoire). Capillary gas chromatography was used to identify and determine carbohydrates in soil profile under 4 tropical ecosystems: gallery and plateau forests, and grass and shrub tree savannas. Forest soils were higher in organic matter than savanna soils (0.50–2.96% C v. 0.53–1.22% C). The carbohydrate-C content of soils, expressed as percentage of total soil organic C, was low, a likely consequence of the tropical climate that promotes a rapid decomposition of surface plant debris. The carbohydrate-C content was higher under savanna soils (5–7%) than under forest soils (3–4%). Glucose, ribose, mannose, xylose, and galactose were the 5 most abundant extractable monosaccharides in all soils. Between them, only xylose and ribose are controlled by the vegetation type. The [(galactose + mannose) : (arabinose + xylose)] and [mannose : xylose] ratios suggested that most soil sugars derive from microbial biomass. The large abundance of microbial carbohydrates indicates intense microbial activities in the soil, and then rapid decomposition of soil organic matter favoured by the long wet season, with high temperatures and soil water availability at the site study. Results suggest clearly that the climate likely controls the amount and composition of carbohydrates in Lamto soils.
Modelling velocity and retardation factor of a nonlinearly sorbing solute plume
Authors: Mojid M. A. , Vereecken H.
Published: September 2005

This study, considering evidences of slower sorption rates of reactive solutes in the field than in laboratory, quantifies the velocity and retardation factor of a sodium fluorescein (uranin: C20H10Na2O5) plume over its travel path in a heterogeneous aquifer. The transport process of uranin was evaluated by batch experiments and from breakthrough curves (BTCs) by using solute-transport models. Method of time moments analysed BTCs of uranin and bromide to derive the velocity and retardation factor.
A constant velocity of the bromide plume, 0.64 m/day, implies a spatially and temporally uniform velocity field where groundwater flows at steady-state condition. A large dimensionless index (195) of chemical non-equilibrium model and equilibrium distribution coefficient (0.32) of uranin are indicative of chemical non-equilibrium transport process.
The travel time of uranin plume increases asymptotically, following power law, with travel path of the plume. Good agreement of the exponent of power law with that of Freundlich isotherm is a result of nonlinear sorption, and provides an independent way of estimating the exponent of the isotherm. The local velocity of the plume decreases asymptotically in time and is predicted by the derivative of the relationship between travel path and travel time of the plume. The retardation factor, which increases in time following power law, when estimated from the local velocity, is considerably larger than that estimated from travel time of the plume.
Effect of gypsum and polyacrylamides on water turbidity and infiltration in a sodic soil
Authors: Sivapalan S.
Published: September 2005

Water ponded on sodic soils can develop turbidity problems which seriously affect rice crop establishment. A total of 19 polyacrylamide products were assessed for their effectiveness to control water turbidity in a sodic soil under laboratory conditions. Anionic polyacrylamides were more effective than cationic or non-ionic polyacrylamides. When combined with gypsum, polyacrylamides were found to be more effective than when applied alone. A split application strategy was more efficient than continuous application of polyacrylamide treatments. Different rates of polyacrylamides at 2.5, 5, and 10 kg/ha did not show significant difference in controlling water turbidity. Selected polyacrylamides were also tested on soil columns to study their effect on infiltration and percolation of water through the soil. Results showed that polyacrylamides combined with low rates of gypsum did not modify the infiltration pattern to a greater extent. This study demonstrated that anionic polyacrylamides applied with small quantities of gypsum through a split application strategy would be an appropriate technique to overcome water turbidity problems in sodic soils.
Exploring pedogenesis via nuclide-based soil production rates and OSL-based bioturbation rates
Authors: Wilkinson Marshall T. , Humphreys Geoff S.
Published: September 2005

New dating techniques are available for soil scientists to test fundamental pedogenic ideas. Recent developments in applications of terrestrial in situ cosmogenic nuclides (TCN) from bedrock and saprolite allow the derivation of soil production rates, at scales ranging from local (sub-hillslope) to catchment wide, generally averaged over timescales of 104–105 years. Where soil depths are relatively constant over time, soil production rates equal transport rates and are thus essential to establishing sustainable erosion rates. TCN also allow the form of the soil production function to be compared to theoretical models—a difficult task previously. Furthermore, parameterised soil production functions can now be incorporated into numerical surface process models to test landscape evolution ideas.
Bedrock and saprolite conversion to soil is demonstrably dependent on the overlying soil depth, and there is general agreement that weathering declines exponentially beyond maximum soil production, consistent with theory. Whether maximum soil production occurs under a finite or non-existent soil cover at particular sites remains unresolved. We suggest that, in general, soil production from saprolite declines exponentially with increasing depth, while production from bedrock follows a humped function.
Estimates of the role of flora, fauna and processes such as freeze–thaw that mix soil mantles to depth, have been limited prior to optically stimulated luminescence (OSL) dating techniques. Recently derived OSL mixing rates extend the magnitude of previous partial, short-term bioturbation rates. In fact, bioturbation appears to be the most active pedogenic process operating in many soils, with freeze–thaw environments a noted exception. Although bioturbation far outweighs soil production, it does not always lead to homogenisation as is often reported. We maintain that the above-ground component of bioturbation, i.e. mounding, may alone, or particularly when combined with particle sorting via rainwash processes, lead to horizonisation and texture contrast soils in those materials that can be sorted such as mixtures of sand and clay. Together, TCN- and OSL-based estimates of hillslope soil transport and bioturbation, suggest significant rates of downslope soil mantle movement coupled with rapid mixing, contrary to in situ soil development models.
Ultra-violet, visible, near-infrared, and mid-infrared diffuse reflectance spectroscopic techniques to predict several soil properties
Authors: Pirie Adam , Singh Balwant , Islam Kamrunnahar
Published: September 2005

Reflectance spectroscopy techniques in the ultraviolet, visible, near-infrared and mid-infrared regions are alternatives for many traditional laboratory methods for measuring soil properties. However, debate exists over whether the near-infrared (700–2500 nm) or the mid-infrared (MIR, 2500–25000 nm) region of the electromagnetic spectrum is more useful for predicting soil properties. Therefore, the aim of this study was to compare UV-VIS-NIR and MIR spectroscopic techniques to predict several soil properties. A total of 415 surface and subsurface soil samples were collected from widely spread locations within New South Wales and south-eastern Queensland of Australia to model the proposed hypothesis. Principal component regression analysis (PCR) was used to develop calibration and validation models from soil spectra and reference laboratory values. The models developed using MIR spectra achieved higher prediction accuracy (regression coefficient, r2 = 0.62–0.85) for pH, organic carbon, clay, sand, CEC, and exchangeable Ca and Mg than that obtained by UV-VIS-NIR spectra (r2 = 0.28–0.76). PCR models were also developed for the combined spectral regions (UV-VIS-NIR+MIR). The models developed using combined spectra were also found to predict pH, organic carbon, clay, sand, CEC, and exchangeable Ca and Mg with acceptable accuracy (r2 = 0.59–0.79). The results of this study indicate that MIR spectra are better than UV-VIS-NIR spectra for estimation of common soil properties.
Intersheet rearrangement of polypeptides during nucleation of β-sheet aggregates
Authors: Petty Sarah A. , Decatur Sean M.
Published: September 2005

Many neurodegenerative diseases are characterized by the accumulation of amyloid fibers in the brain, which can occur when a protein misfolds into an extended β-sheet conformation. The nucleation of these β-sheet aggregates is of particular interest, not only because it is the rate-determining step toward fiber formation but also because early, soluble aggregate species may be the cytotoxic entities in many diseases. In the case of the prion peptide H1 (residues 109–122 of the prion protein) stable amyloid fibers form only after the β-strands of the peptide have adopted their equilibrium antiparallel β-sheet configuration with residue 117 in register across all strands. In this article, we present the kinetic details of the realignment of these β-strands from their fastformed nonequilibrium structure, which has no regular register of the strands, into the more ordered β-sheets capable of aggregating into stable fibers. This process is likely the nucleating step toward the formation of stable fibers. Isotope-edited IR spectroscopy is used to monitor the alignment of the β-strands by the introduction of a13C-labeled carbonyl at residue 117. Nonexponential kinetics is observed, with a complex dependence on concentration. The results are consistent with a mechanism in which the β-sheet realigns by both the repeated detachment and annealing of strands in solution and reptation of polypeptide strands within an aggregate.
Cochaperone immunophilin FKBP52 is critical to uterine receptivity for embryo implantation
Authors: Tranguch Susanne , Cheung-Flynn Joyce , Daikoku Takiko , Prapapanich Viravan , Cox Marc B. , Xie Huirong , Wang Haibin , Das Sanjoy K. , Smith David F. , Dey Sudhansu K.
Published: September 2005

Embryo implantation in the uterus is a critical step in mammalian reproduction, requiring preparation of the uterus receptive to blastocyst implantation. Uterine receptivity, also known as the window of implantation, lasts for a limited period, and it is during this period blastocysts normally implant. Ovarian steroid hormones estrogen and progesterone (P
4
) are the primary regulators of this process. The immunophilin FKBP52 serves as a cochaperone for steroid hormone nuclear receptors to govern appropriate hormone action in target tissues. Here we show a critical role for FKBP52 in mouse implantation. This immunophilin has unique spatiotemporal expression in the uterus during implantation, and females missing the
Fkbp52
gene have complete implantation failure due to lack of attainment of uterine receptivity. The overlapping uterine expression of FKBP52 with nuclear progesterone receptor (PR) in wild-type mice together with reduced P
4
binding to PR, attenuated PR transcriptional activity and down-regulation of several P
4
-regulated genes in uteri of
Fkbp52
-/-
mice, establishes this cochaperone as a critical regulator of uterine P
4
function. Interestingly, ovulation, another P
4
-mediated event, remains normal. Collectively, the present investigation provides evidence for an
in vivo
role for this cochaperone in regulating tissue-specific hormone action and its critical role in uterine receptivity for implantation.
Amino acids mediate mTOR/raptor signaling through activation of class 3 phosphatidylinositol 3OH-kinase
Authors: Nobukuni Takahiro , Joaquin Manel , Roccio Marta , Dann Stephen G. , Kim So Young , Gulati Pawan , Byfield Maya P. , Backer Jonathan M. , Natt Francois , Bos Johannes L. , Zwartkruis Fried J. T. , Thomas George
Published: September 2005

During the evolution of metazoans and the rise of systemic hormonal regulation, the insulin-controlled class 1 phosphatidylinositol 3OH-kinase (PI3K) pathway was merged with the primordial amino acid-driven mammalian target of rapamycin (mTOR) pathway to control the growth and development of the organism. Insulin regulates mTOR function through a recently described canonical signaling pathway, which is initiated by the activation of class 1 PI3K. However, how the amino acid input is integrated with that of the insulin signaling pathway is unclear. Here we used a number of molecular, biochemical, and pharmacological approaches to address this issue. Unexpectedly, we found that a major pathway by which amino acids control mTOR signaling is distinct from that of insulin and that, instead of signaling through components of the insulin/class 1 PI3K pathway, amino acids mediate mTOR activation by signaling through class 3 PI3K, hVps34.
Spatial regulation of the cAMP-dependent protein kinase during chemotactic cell migration
Authors: Howe Alan K. , Baldor Linda C. , Hogan Brian P.
Published: September 2005

Historically, the cAMP-dependent protein kinase (PKA) has a paradoxical role in cell motility, having been shown to both facilitate and inhibit actin cytoskeletal dynamics and cell migration. In an effort to understand this dichotomy, we show here that PKA is regulated in subcellular space during cell migration. Immunofluorescence microscopy and biochemical enrichment of pseudopodia showed that type II regulatory subunits of PKA and PKA activity are enriched in protrusive cellular structures formed during chemotaxis. This enrichment correlates with increased phosphorylation of key cytoskeletal substrates for PKA, including the vasodilator-stimulated phosphoprotein (VASP) and the protein tyrosine phosphatase containing a PEST motif. Importantly, inhibition of PKA activity or its ability to interact with A kinase anchoring proteins inhibited the activity of the Rac GTPase within pseudopodia. This effect correlated with both decreased guanine nucleotide exchange factor activity and increased GTPase activating protein activity. Finally, inhibition of PKA anchoring, like inhibition of total PKA activity, inhibited pseudopod formation and chemotactic cell migration. These data demonstrate that spatial regulation of PKA via anchoring is an important facet of normal chemotactic cell movement.
Innovation, Skill Needs and Training in a Rural Community
Authors: Selby Smith Chris , Ferrier Fran
Published: September 2005

Difficult challenges face the Gannawarra Shire in northern Victoria, including competing increasingly in global markets, environmental degradation and changing consumer preferences. Education, training and skill development are one way of addressing the challenges. A survey of 68 enterprises (distinguishing between growing, consolidating and declining enterprises) suggested, inter alia, that innovation is an essential element in Gannawarra’s response to the challenges it faces and that enterprises requiring more training differ significantly from those requiring different types of education and training. The ‘story’ of Gannawarra’s challenges and its efforts to address them provide insights which are likely to be useful elsewhere.
Social Marketing Applied to Economic Reforms
Authors: Andreasen Alan R. , Herzberg Benjamin
Published: September 2005

As social marketers seek to broaden their purview to include upstream applications, they are handicapped by the lack of examples of such applications. This article represents a retrofit of social marketing approaches developed by Andreasen to a major international intervention in Bosnia Herzegovina to reduce the array of impediments to private sector business investment and growth. The Bulldozer Initiative project, run by Herzberg, focused on two target audiences, businessmen and politicians, and sought participation by the former and support and legislative change from the latter. The Initiative was highly successful and resulted in a major change in the business climate and wide praise from an array of international agencies. Major components of the program closely conformed to ways in which social marketers would have constructed them.
Too much or too little? Prescription drug use in a nationwide prison population
Authors: Kjelsberg E. , Hartvig P.
Published: September 2005

Aim ‐ To describe prescription drug use in a nationwide prison population and compare it with contemporary drug use in other relevant populations as well as in a prison population 25 years ago. Method ‐ Detailed medication sheets from 37 prisons, covering 90% of the Norwegian prison population, were collected. All drugs were transcribed into the Anatomical Therapeutic Chemical classification system, and Defined Daily Doses/100 inmates were calculated. Data enabling relevant comparisons were gathered from reliable sources. Results ‐ Among the 2,617 inmates investigated, 48% used no medication. Sixteen percent used both psychotropic and somatic drugs, 17% psychotropic drugs only, and 19% somatic drugs only. Strong correlations between drug use and gender, age, and prison characteristics were demonstrated. Psychotropic drug use was higher than in the general population but lower than in a psychiatric hospital unit. Somatic drug use was lower than in the general population, except non‐steroid antiinflammatory
agents, antihistamines, and drugs to alleviate obstructive airway diseases. Psychotropic drug use, particularly antidepressant use, was higher than in prisons 25 years ago.
Conclusion ‐ High levels of use of all psychotropic and a number of somatic drugs were demonstrated in this nationwide prison population. Treatment studies are needed in order to ascertain whether the high levels of use of particularly psychotropic medications are indeed improving the mental health of prisoners.
Independent roles for IL-2 and GATA-3 in stimulating naive CD4+ T cells to generate a Th2-inducing cytokine environment
Authors: Yamane Hidehiro , Zhu Jinfang , Paul William E.
Published: September 2005

T cell receptor (TCR) signaling plays an important role in early interleukin (IL)-4 production by naive CD4+ T cells. This “antigen-stimulated” early IL-4 is sufficient for in vitro Th2 differentiation. Here, we provide evidence that early IL-4 production by naive CD4+ T cells stimulated with cognate peptide requires TCR-induced early GATA-3 expression and IL-2 receptor signaling, both of which are controlled by the degree of activation of extracellular signal-regulated kinase (ERK). Stimulation of naive CD4+ T cells from TCR transgenic mice with low concentrations of peptide-induced IL-2–dependent STAT5 phosphorylation, IL-4-independent early GATA-3 expression, and IL-4 production. Neutralization of IL-2 abolished early IL-4 production without affecting early GATA-3 expression. In addition, naive CD4+ T cells from GATA-3 conditional KO mice failed to produce early IL-4 in response to TCR/CD28 stimulation. Stimulation with high concentrations of peptide abrogated early GATA-3 expression and IL-2–dependent STAT5 phosphorylation, and resulted in the failure to produce early IL-4. This high concentration–mediated suppression of early IL-4 production was reversed by blockade of the ERK pathway. A MEK inhibition rescued early GATA-3 expression and responsiveness to IL-2; these cells were now capable of producing early IL-4 and undergoing subsequent Th2 differentiation.
Association between Mannose-Binding Lectin Gene Polymorphisms and Susceptibility to Severe Acute Respiratory Syndrome Coronavirus Infection
Authors: Zhang Hongxing , Zhou Gangqiao , Zhi Lianteng , Yang Hao , Zhai Yun , Dong Xiaojia , Zhang Xiumei , Gao Xue , Zhu Yunping , He Fuchu
Published: September 2005

BackgroundGenetic determinants of susceptibility to severe acute respiratory syndrome coronavirus (SARS-CoV) infection remain unknown. We assessed whether mannose-binding lectin (MBL) gene polymorphisms were associated with susceptibility to SARS-CoV infection or disease severity in an ethnically homogeneous population born in northern China

MethodsThe frequencies of 1 mutation in codon 54 and 3 promoter polymorphisms at nt −550, −221, and 4 were ascertained in 352 patients with SARS and 392 control subjects, by means of polymerase chain reaction direct sequencing

ResultsOf 352 patients with SARS and 392 control subjects, 120 (34.4%) and 91 (23.2%) were carriers of the codon 54 variant, respectively (odds ratio [OR], 1.73 [95% confidence interval {CI}, 1.25–2.39]; P=.00086). A total of 123 (36.0%) of 352 patients with SARS and 100 (25.5%) of 392 control subjects had haplotype pairs associated with medium or low expression of MBL (OR, 1.67 [95% CI, 1.21–2.29]; P=.00187). The population-attributable fraction of patients with SARS that was associated with having the codon 54 variant was 20.1% (95% CI, 7.9%–32.3%)

Conclusions MBL gene polymorphisms were significantly associated with susceptibility to SARS-CoV infection; this might be explained by the reduced expression of functional MBL secondary to having the codon 54 variant
On the Bergman metric of pseudoconvex domains in a complex projective space
Authors: Chen Bo-Yong
Published: September 2005

We prove a localization principle of the Bergman kernel form and metric for

C
2

C^2

pseudoconvex domains in the complex projective space. An estimate of the Bergman distance is also given.
A stability property for linear groups
Authors: Anton Marian
Published: September 2005

For suitable rings of integers

R
R

, we show that the mod

p
p

group cohomology for

G

L

n
+
3
p
−
5

(
R
)

GL_{n+3p-5}(R)

comes from

G

L
∞

(
R
)

GL_\infty (R)

when restricted to the diagonal matrices

D
n

(
R
)

D_n(R)

for all ranks

n
≥
2

n\ge 2

.
Eigenvalue inequalities in an embeddable factor
Authors: Bercovici Hari , Li Wing
Published: September 2005

We provide a characterization of the possible eigenvalues of the sum of two selfadjoint elements of a II

1

_{1}

factor which can be embedded in the ultrapower

R

ω

\mathcal {R}^{\omega }

of the hyperfinite II

1

_{1}

factor.
The power of the tangent bundle of the real projective space, its complexification and extendibility
Authors: Kobayashi Teiichi , Yamasaki Hironori , Yoshida Toshio
Published: September 2005

We establish the formulas on the power

τ
k

\tau ^k

of the tangent bundle

τ
=
τ
(
R

P
n

)

\tau =\tau (RP^n)

of the real projective

n
n

-space

R

P
n

RP^n

and its complexification

c

τ
k

c\tau ^k

, and apply the formulas to the problem of extendibility and stable extendiblity of

τ
k

\tau ^k

and

c

τ
k

c\tau ^k

.
Zero sets and interpolating sets in Fock spaces
Authors: Tung James
Published: September 2005

An example is constructed to show that interpolating sets for Fock spaces are not necessarily zero sets.
Buchsbaum Stanley–Reisner rings with minimal multiplicity
Authors: Terai Naoki , Yoshida Ken-ichi
Published: September 2005

In this paper, we study Buchsbaum Stanley–Reisner rings with linear free resolution. We introduce the notion of Buchsbaum Stanley–Reisner rings with minimal multiplicity of initial degree

q
q

, which extends the notion of Buchsbaum rings with minimal multiplicity defined by Goto. As an application, we give many examples of non-Cohen–Macaulay Buchsbaum Stanley–Reisner rings with linear resolution.
The big slice phenomena in M-embedded and L-embedded spaces
Authors: Pérez Ginés
Published: September 2005

We obtain sufficient conditions on an M-embedded or L-embedded space so that every nonempty relatively weakly open subset of its unit ball has norm diameter 2. We prove that, up to renorming, this holds for every Banach space containing

c
0

c_0

and, as a consequence, for every proper M-ideal. The result obtained for L-embedded spaces can be applied to show that the above property is satisfied for every predual of an atomless real JBW*-triple. As a consequence, a characterization of the Radon-Nikodym property is obtained in this setting, showing that a predual of a real JBW*-triple E verifies the Radon-Nikodym property if, and only if, E is the

l

∞

l_{\infty }

-sum of real type I triple factors.
On vectorial polynomials and coverings in characteristic 3
Authors: Crespo Teresa , Hajto Zbigniew
Published: September 2005

For

K
K

a field containing the finite field

F

9

\mathbb {F}_9

we give explicitly the whole family of Galois extensions of

K
K

with Galois group

2

S
4

∗

Q
8

2S_4*Q_8

or

2

S
4

∗

D
8

2S_4*D_8

and determine the discriminant of such an extension.
Multiplicities of representations in spaces of modular forms
Authors: Hsie Bin
Published: September 2005

This paper shows that for a given irreducible representation

ρ
\rho

of

Γ

/

Γ

1

\Gamma /\Gamma _{1}

, the two functions dim(

M

k

(

Γ

1

,
ρ
)

M_{k}(\Gamma _{1},\rho )

) and dim(

S

k

(

Γ

1

,
ρ
)

S_{k}(\Gamma _{1},\rho )

) of

k
k

are almost linear functions.
A construction of a robust family of exponential attractors
Authors: Gatti Stefania , Grasselli Maurizio , Miranville Alain , Pata Vittorino
Published: September 2005

Given a dissipative strongly continuous semigroup depending on some parameters, we construct a family of exponential attractors which is robust, in the sense of the symmetric Hausdorff distance, with respect to (even singular) perturbations.
The Chromokinesin Kid Is Required for Maintenance of Proper Metaphase Spindle Size
Authors: Tokai-Nishizumi Noriko , Ohsugi Miho , Suzuki Emiko , Yamamoto Tadashi
Published: September 2005

The human chromokinesin Kid/kinesin-10, a plus end-directed microtubule (MT)-based motor with both microtubule- and DNA-binding domains, is required for proper chromosome alignment at the metaphase plate. Here, we performed RNA interference experiments to deplete endogenous Kid from HeLa cells and confirmed defects in metaphase chromosome arm alignment in Kid-depleted cells. In addition, we noted a shortening of the spindle length, resulting in a pole-to-pole distance only 80% of wild type. The spindle microtubule-bundles with which Kid normally colocalize became less robust. Rescue of the two Kid deficiency phenotypes—imprecise chromosome alignment at metaphase and shortened spindles— exhibited distinct requirements. Mutants lacking either the DNA-binding domain or the MT motor ATPase failed to rescue the former defect, whereas rescue of the shortened spindle phenotype required neither activity. Kid also exhibits microtubule bundling activity in vitro, and rescue of the shortened spindle phenotype and the bundling activity displayed similar domain requirements, except that rescue required a coiled-coil domain not needed for bundling. These results suggest that distinct from its role in chromosome movement, Kid contributes to spindle morphogenesis by mediating spindle microtubules stabilization.