bluuebunny/crossref_metadata_2025 huggingface dataset:
Innovative strategies for on-farm weed management in organic carrot
Authors: Peruzzi Andrea , Ginanni Marco , Fontanelli Marco , Raffaelli Michele , Bàrberi Paolo
Published: December 2007

Weed management is often the most troublesome technical problem to be solved in organic farming, especially in poorly competitive crops like vegetables. A four-year (2000–2003) series of trials was established to assess the possibility of adopting an innovative non-chemical weed management system in organic carrot grown on the Fucino plateau, i.e., the most important carrot-growing area in Italy. The system utilized for physical weed control was based first on a false seedbed technique followed by pre-sowing weed removal, performed with a special 2 m wide 6-row spring-tine harrow. Prior to crop emergence, a pass with a flame weeder equipped with four 50 cm wide-open flame burners was also performed. Post-emergence weed control consisted of one or more hoeing passes with a purpose-designed 11-tine precision hoe equipped with spring implements (torsion weeders and vibrating tines), in addition to hand weeding. This innovative system was applied to a novel planting pattern (sowing in ten individual rows within 2 m wide beds) and compared to the standard management system of the area (sowing within 2 m wide beds but in five bands, use of spring-tine harrowing and flame weeding pre-emergence and of traditional hoeing post-emergence). The new system was tested in different commercial farms including both early and late-sown carrot. Assessments included machine operative characteristics, labor time, weed density and biomass, crop root yield and yield quality, and economic data (physical weed control costs and crop gross margin). Compared to the standard system, the innovative system usually resulted in reduced labor time (from 28 to 40%) and total costs for physical weed control (on average −416 € ha−1). Use of the precision hoe resulted in intra-row weed reduction ranging from 65 to 90%, which also led to a marked reduction in the labor required for hand weeding. In 2001 the two systems did not differ in terms of yield and yield quality, whereas in 2002 and 2003 the innovative system showed a higher mean density of carrot plants (from 28 to 55%), root yield (from 30 to 42%), and gross margin (from 40 to 100%). Carrot yield was higher in farms which adopted an early sowing whereas root commercial quality was somewhat variable between systems and years. In general, results obtained with the innovative management system look very promising.
Farmer perceptions of soil quality and their relationship to management-sensitive soil parameters
Authors: Gruver J.B. , Weil R.R.
Published: December 2007

A critical step in the quantification of soil quality (SQ) is the selection of SQ benchmarks. The benchmarks used in this study were SQ ratings made by 32 farmer collaborators representing a range of farming systems, scales of operation and geographic locations in the Mid-Atlantic region of USA. Soils from 45 pairs of sites identified by their farmers as having good and poor SQ were sampled over three seasons and analyzed for 19 soil parameters. Farmer judgments of SQ were based on many factors, most commonly soil organic matter, crop performance, soil water availability and erosion history. Selected individual soil parameters were normalized and integrated into an additive SQ index (SQI). Three additional indices were developed using discriminant analysis. The level of agreement between individual parameters, SQIs and farmer SQ ratings was evaluated using paired t-tests and mean percent difference values. The additive SQI was found to have the highest level of agreement with farmer SQ ratings (P<0.0001), demonstrating that a linear combination of soil parameters can be assembled that is more in agreement with holistic SQ criteria, such as farmer SQ ratings, than individual soil parameters. Extractable C from microwave (MW) sterilized soil (a measure of microbial biomass) was the individual parameter that best agreed with farmer SQ ratings (P<0.0001). Five additional soil C parameters, as well as aggregate stability, also agreed well with farmer SQ ratings (all P values <0.0005). The three parameters with the highest ratio of mean percent difference to coefficient of variation (an indication of parameter reliability) were extractable C from MW sterilized soil, anthrone reactive C and macroaggregate stability (14.2, 7.7 and 3.7, respectively). Mineral fertility parameters (pH, Ca, Ca:Mg ratio, P and K) were not significantly related to farmer SQ ratings (P values >0.05). The strong relationships observed between soil C parameters, soil structural parameters and farmer SQ ratings suggest that efforts to improve SQ in the study region should focus on monitoring and enhancement of soil C and soil structure.
Applicability of Central Auditory Processing Disorder Models
Authors: Jutras Benoît , Loubert Monique , Dupuis Jean-Luc , Marcoux Caroline , Dumont Véronique , Baril Michèle
Published: December 2007

Purpose

Central auditory processing disorder ([C]APD) is a relatively recent construct that has given rise to 2 theoretical models: the Buffalo Model and the Bellis/Ferre Model. These models describe 4 and 5 (C)APD categories, respectively. The present study examines the applicability of these models to clinical practice. Neither of these models was based on data from peer-reviewed sources.

Method

This is a retrospective study that reviewed 178 records of children diagnosed with (C)APD, of which 48 were retained for analysis.

Results

More than 80% of the children could be classified into one of the Buffalo Model categories, while more than 90% remained unclassified under the Bellis/Ferre Model. This discrepancy can be explained by the fact that the classification of the Buffalo Model is based primarily on a single central auditory test (Staggered Spondaic Word), whereas the Bellis/Ferre Model classification uses a combination of auditory test results.

Conclusion

The 2 models provide a conceptual framework for (C)APD, but they must be further refined to be fully applicable in clinical settings.
Program for the Conservation and Promotion of Hearing Among Adolescents
Authors: Serra Mario R. , Biassoni Ester C. , Hinalaf María , Pavlik Marta , Pérez Villalobo Jorge , Curet Carlos , Minoldo Gloria , Abraham Silvia , Moreno Barral José , Reynoso Raúl , Barteik María E. , Joekes Silvia , Yacci María R.
Published: December 2007

Purpose

We describe a program for the promotion of hearing conservation aimed at the adolescent population. The intent of our program is to (a) detect hearing disorders early, as well as to establish their relation to psychosocial and acoustic factors; (b) devise a follow-up procedure to study relevant variables; (c) evaluate the relation between hearing disorders and genetic factors, and (d) raise the social awareness of the effects of noise and its consequences.

Method

This program, designed to be carried out over a 7-year period, focuses on participants from technical schools in the city of Cordoba, Argentina. Every student will be examined at age 14–15 years and will be reexamined at age 17–18. There will be a yearly follow-up in those cases in which disorders are detected.

Results and Conclusions

We discuss the organization and planning of this program, together with its launching in the first of the selected schools. We also describe the findings on the following topics: (a) the hearing data on adolescents (age 14–15 years); (b) their recreational habits, personality traits, and attitudes; and (c) the sound immision characteristics these individuals are exposed to during recreational activities.
Comparison of Audiometric Screening Criteria for the Identification of Noise-Induced Hearing Loss in Adolescents
Authors: Meinke Deanna K. , Dice Noel
Published: December 2007

Purpose

To ascertain whether current pure-tone school hearing screening criteria used across the United States are adequate for the early identification of noise-induced hearing loss (NIHL) in adolescents.

Method

School-based pure-tone hearing screening protocols were collected, reviewed, and consolidated from 46 state agencies. A retrospective categorical analysis of air-conduction audiometric thresholds from a computerized database of 9th-grade (n= 376) and 12th-grade (n= 265) students from a suburban high school was conducted. The database analysis was designed to determine whether each screening protocol would identify high-frequency notched audiometric configurations suggestive of NIHL when using the noise notch criteria described by A. S. Niskar et al. (2001).

Results

All of the school-based hearing screening criteria identified significantly (p≤ .05) fewer students with a high-frequency notch (HFN) than the noise notch protocol regardless of screening decibel level specified. Over half of the school-based hearing screening protocols used in the United States will identify only 22% of the students with an HFN and consequently would fail to detect a potential NIHL.

Conclusions

Currently implemented school-based hearing screening guidelines are nonstandardized and inadequate for the early identification of NIHL. This denies the majority of students the opportunity to receive early intervention and to prevent further progression of NIHL. It is necessary to identify, standardize, and implement effective and efficient screening or monitoring programs for the early detection and prevention of NIHL in adolescents.
Laser induced fluorescence of Mg-phthalocyanine in He droplets: Evidence for fluxionality of large H2 clusters at 0.38K
Authors: Kuma Susumu , Goto Haruka , Slipchenko Mikhail N. , Vilesov Andrey F. , Khramov Alexander , Momose Takamasa
Published: December 2007

The formation of Ar and H2 clusters, having up to 900 particles in helium droplets, has been studied via laser induced fluorescence of attached Mg-phthalocyanine (Mg-Pc) molecules. In the experiments, one Mg-Pc molecule in average was added to each He droplet either before or after the cluster species, and the shift of the spectrum of the Mg-Pc molecules was studied as a function of the cluster size. For Ar clusters, about a factor of 2 smaller matrix shift was observed for the late pickup of the Mg-Pc molecules as compared with the prior pickup, indicating that in the former case, the Mg-Pc molecules reside on the surface of the preformed Ar clusters. On the other hand, the spectra of the Mg-Pc molecules attached to H2 clusters are independent of the pickup order, which is consistent with Mg-Pc molecules residing near the center of the H2 clusters in both cases. Therefore H2 clusters remain fluxional in helium droplets at T=0.38K. No significant differences in the spectra were observed between the para-H2 and ortho-H2 clusters.
Decoupling of exchange and persistence times in atomistic models of glass formers
Authors: Hedges Lester O. , Maibaum Lutz , Chandler David , Garrahan Juan P.
Published: December 2007

With molecular dynamics simulations of a fluid mixture of classical particles interacting with pairwise additive Weeks-Chandler-Andersen potentials, we consider the time series of particle displacements and thereby determine the distributions for local persistence times and local exchange times. These basic characterizations of glassy dynamics are studied over a range of supercooled conditions and were shown to have behaviors, most notably decoupling, similar to those found in kinetically constrained lattice models of structural glasses. Implications are noted.
Seed-layer mediated orientation evolution in dielectric Bi–Zn–Ti–Nb–O thin films
Authors: Kim Jin Young , Noh Jun Hong , Lee Sangwook , Yoon Sung-Hun , Cho Chin Moo , Hong Kug Sun , Jung Hyun Suk , Lee Jung-Kun
Published: December 2007

Highly (hhh)-oriented pyrochlore Bi–Zn–Ti–Nb–O (BZTN) thin films were fabricated via metal-organic decomposition using orientation template layers. The preferred orientation was ascribed to the interfacial layer, the lattice parameter of which is similar to BZTN. High-resolution transmission electron microscopy supported that the interfacial layer consists of Bi and Pt. The (hhh)-oriented thin films exhibited a highly insulating nature enabling feasible applications in electronic devices, particularly voltage tunable application. The BZTN thin films did not show any apparent dielectric anisotropy and the slightly enhanced dielectric properties were discussed in connection to the internal stress and the grain boundary effect.
Measurement of tack of Newtonian liquids on porous substrates
Authors: Jha Prateek K. , Tirumkudulu Mahesh S.
Published: December 2007

Probe-tack experiments of Tirumkudulu et al. [Phys. Fluids 15, 1588 (2003)] have shown that squeeze flow of Newtonian liquids on flat, impermeable substrates can be successfully modeled using the lubrication approximation. Here, we present a model for squeeze flow of Newtonian liquids on porous substrates where the flow in the gap is coupled to the fluid flow in the porous media. The competition of spreading and imbibition of liquid on a partially saturated porous substrate determines the force versus gap profile in both the squeeze (compression) and pull-off (tension) modes. The finite difference method was used to discretize the lubrication equation in the gap while boundary element method was employed to solve for flow in the porous substrate. The model predicts a lower magnitude of force for porous substrates in both compression and tension modes compared to that for impermeable substrates. Experiments on porous alumina substrates with Newtonian liquids show close agreement with the model predictions in both compression and tension modes when the gap is corrected for the obliqueness of the confining surfaces. Cavitation is predicted for some cases in the tension mode when the pressure in the gap reduced below the vapor pressure of liquid.
Theoretical investigation of the energies and geometries of photoexcited uranyl(VI) ion: A comparison between wave-function theory and density functional theory
Authors: Réal Florent , Vallet Valérie , Marian Christel , Wahlgren Ulf
Published: December 2007

In order to assess the accuracy of wave-function and density functional theory (DFT) based methods for excited states of the uranyl(VI) UO22+ molecule excitation energies and geometries of states originating from excitation from the σu, σg, πu, and πg orbitals to the nonbonding 5fδ and 5fϕ have been calculated with different methods. The investigation included linear-response CCSD (LR-CCSD), multiconfigurational perturbation theory (CASSCF∕CASPT2), size-extensivity corrected multireference configuration interaction (MRCI) and AQCC, and the DFT based methods time-dependent density functional theory (TD-DFT) with different functionals and the hybrid DFT∕MRCI method. Excellent agreement between all nonperturbative wave-function based methods was obtained. CASPT2 does not give energies in agreement with the nonperturbative wave-function based methods, and neither does TD-DFT, in particular, for the higher excitations. The CAM-B3LYP functional, which has a corrected asymptotic behavior, improves the accuracy especially in the higher region of the electronic spectrum. The hybrid DFT∕MRCI method performs better than TD-DFT, again compared to the nonperturbative wave-function based results. However, TD-DFT, with common functionals such as B3LYP, yields acceptable geometries and relaxation energies for all excited states compared to LR-CCSD. The structure of excited states corresponding to excitation out of the highest occupied σu orbital are symmetric while that arising from excitations out of the πu orbitals have asymmetric structures. The distant oxygen atom acquires a radical character and likely becomes a strong proton acceptor. These electronic states may play an important role in photoinduced proton exchange with a water molecule of the aqueous environment.
Rayleigh–Bénard flow of a rarefied gas and its attractors. III. Three-dimensional computer simulations
Authors: Stefanov S. , Roussinov V. , Cercignani C.
Published: December 2007

We investigate the three-dimensional Rayleigh–Bénard flow for a set of different Knudsen and Froude numbers at a fixed temperature ratio r=0.1, as well as for different aspect ratios. We observe a variety of stable vortex structures in the form of rolls, squares, and more complicated polygonal patterns. For sufficiently low Knudsen numbers, the existence of irregular regimes was confirmed. Two numerical approaches (the direct simulation Monte Carlo method and a finite-difference method for the Navier–Stokes equation) are used and the results show a satisfactory agreement.
Achieving large slip with superhydrophobic surfaces: Scaling laws for generic geometries
Authors: Ybert Christophe , Barentin Catherine , Cottin-Bizonne Cécile , Joseph Pierre , Bocquet Lydéric
Published: December 2007

We investigate the hydrodynamic friction properties of superhydrophobic surfaces and quantify their superlubricating potential. On such surfaces, the contact of the liquid with the solid roughness is minimal, while most of the interface is a liquid-gas one, resulting in strongly reduced friction. We obtain scaling laws for the effective slip length at the surface in terms of the generic surface characteristics (roughness length scale, depth, solid fraction of the interface, etc.). These predictions are successfully compared to numerical results in various geometries (grooves, posts or holes). This approach provides a versatile framework for the description of slip on these composite surfaces. Slip lengths up to 100μm are predicted for an optimized patterned surface.
Coupling effect of electron cyclotron resonance hydrogen plasma and dc biasing in fabricating diamond nanotips
Authors: Wang L. , Cui L. , Zhu X. D. , Wen X. H.
Published: December 2007

The electron cyclotron resonance (ECR) hydrogen plasma with substrate dc biasing was investigated by using a Langmuir probe and optical emission spectroscopy during the formation of nanotips from as-grown diamond films. It is found that the coupling effect between the substrate biasing and the bulk plasma plays an important role in the fluxes of active species incident on the substrate. The energy of incident hydrogen ions is determined by the substrate biasing, while the densities of incident hydrogen ions and atoms are adjusted jointly by the substrate biasing and the bulk plasma. Diamond nanotips were fabricated from as-grown films under ECR-dc conditions. The shapes and sizes of the nanotips vary with the processing parameters, which are correlated with the change of active species on the film surface due to the coupling effect.
Superlens from complementary anisotropic metamaterials
Authors: Li G. X. , Tam H. L. , Wang F. Y. , Cheah K. W.
Published: December 2007

Metamaterials with isotropic property have been shown to possess novel optical properties such as a negative refractive index that can be used to design a superlens. Recently, it was shown that metamaterials with anisotropic property can translate the high-frequency wave vector k values from evanescence to propagating. However, electromagnetic waves traveling in single-layer anisotropic metamaterial produce diverging waves of different spatial frequency. In this work, it is shown that, using bilayer metamaterials that have complementary anisotropic property, the diverging waves are recombined to produce a subwavelength image, i.e., a superlens device can be designed. The simulation further shows that the design can be achieved using a metal/oxide multilayer, and a resolution of 30 nm can be easily obtained in the optical frequency range.
Permeability reduction in porous materials byin situformed silica gel
Authors: Castelijns H. J. , Scherer G. W. , Pel L. , Zitha P. L. J.
Published: December 2007

The effect of in situ formed silica gel on the permeability of a porous material was investigated experimentally. Gelling solutions of tetra-methyl-ortho-silicate (TMOS) and methanol in water were imbibed into dry sandstone plates and cured for several days. The permeability of the untreated sandstone is on the order of 1 μm2, whereas the intrinsic permeability of the silica alcogel is 5–6 orders of magnitude lower. The method of beam bending was employed to measure concurrently the permeability D and Young’s modulus Ep of cylindrical gel rods, prepared from the TMOS-based sol-gel solutions. Second, the permeabilities and moduli of the treated sandstones were measured. For both types of samples the gel structure was varied by varying the concentration of the TMOS in a solution and the pH of the water used. The parameters D and Ep follow from a detailed analysis of the measured relaxation of the load that is applied to the sample under constant deflection. In case of the gels, the relaxation was interpreted using common expressions for hydrodynamic relaxation and viscoelastic (VE) relaxation. It was found that the permeability of the gels decreases with increasing silica content and that acid-catalyzed gels exhibit a significantly lower permeability than base-catalyzed gels. The modulus Ep increases with increasing silica content and aging time. The relaxation data of the sandstone—treated with gel—exhibited a more complex behavior. The normalized load curves showed hydrodynamic relaxation as well as strong and fast VE relaxation. The relaxation data for the rock samples treated with the lowest concentration gel was fitted successfully with the predictions. For higher concentrations the fit was less accurate, but the permeability estimates were within an order of magnitude. The overall permeability of the treated rock is higher than the intrinsic permeability of the gels; this indicates that the gel does not completely fill the pore space. Nevertheless, the permeability is reduced by a factor 104 with respect to untreated sandstone, and therefore the gel adequately blocks the pores.
Electron acceleration by surface plasma waves in double metal surface structure
Authors: Liu C. S. , Kumar Gagan , Singh D. B. , Tripathi V. K.
Published: December 2007

Two parallel metal sheets, separated by a vacuum region, support a surface plasma wave whose amplitude is maximum on the two parallel interfaces and minimum in the middle. This mode can be excited by a laser using a glass prism. An electron beam launched into the middle region experiences a longitudinal ponderomotive force due to the surface plasma wave and gets accelerated to velocities of the order of phase velocity of the surface wave. The scheme is viable to achieve beams of tens of keV energy. In the case of a surface plasma wave excited on a single metal-vacuum interface, the field gradient normal to the interface pushes the electrons away from the high field region, limiting the acceleration process. The acceleration energy thus achieved is in agreement with the experimental observations.
A few-electron vertical In0.56Ga0.44As quantum dot with an insulating gate
Authors: Kita T. , Chiba D. , Ohno Y. , Ohno H.
Published: December 2007

Using an Al2O3 gate insulator by atomic layer deposition and air-bridge drain electrode, we fabricated a quantum dot with few electrons based on an In0.56Ga0.44As resonant tunneling diode structure. Artificial atomic properties manifested themselves in magnetotransport, enabling the determination of effective electron g factors. Results show that the insulating gate structure used here is effective for realizing quantum dots made of narrow-gap semiconductors for studying spin-related phenomena.
Kinetics of Ni3Si2 formation in the Ni2Si–NiSi thin film reaction from in situ measurements
Authors: Kittl J. A. , Pawlak M. A. , Torregiani C. , Lauwers A. , Demeurisse C. , Vrancken C. , Absil P. P. , Biesemans S. , Detavernier C. , Jordan-Sweet J. , Lavoie C.
Published: December 2007

The kinetics of Ni3Si2 formation in the Ni2Si–NiSi thin film reaction were determined from simultaneous in situ x-ray diffraction (XRD) measurements, performed using a synchrotron source, and sheet resistance measurements. Samples consisted of 90nm Ni∕100nm polycrystalline-Si∕SiO2 stacks, of interest for fully silicided gate applications, on (100) Si. After initial formation of a Ni2Si∕NiSi bilayer, these films reacted to form Ni3Si2. The evolution of sheet resistance and of the intensity of XRD peaks were used to extract the fraction of Ni3Si2 formed during ramp and isothermal annealings. A Kissinger analysis was performed for ramp annealing with ramp rates of 1, 3, 5, 9, and 27°C∕s, obtaining the activation energy of Ni3Si2 formation, Ea=1.92±0.15eV. A Kolmogorov-Johnson-Mehl-Avrami analysis was performed for isothermal anneals, finding an Avrami exponent of 2.1±0.2, suggesting two-dimensional growth. This is consistent with a nucleation controlled process for Ni3Si2 formation, with nucleation sites at different positions in the thin film, and subsequent lateral two-dimensional propagation of the transformation front parallel to the film surface. Implications for Ni fully silicided gate applications are discussed.
Host - Guest Complexes of Bicyclic Hexaamine Cryptands - Prediction of Ion Selectivity by Quantum Chemical Calculations. III
Authors: Puchta Ralph , Meier Roland , van Eldik Rudi
Published: December 2007

Density functional theory (B3LYP/LANL2DZp) calculations on the structures and complex formation energies were performed to predict the alkali and alkaline earth ion selectivity of the cryptands 1,4,7,10,13,16,21,24-octaazabicyclo(8.8.8)hexacosane (N2N2N2) 1, 3,6,10,13,16,19-hexaazabicyclo(6.6.6)icosane (sarcophagine) 2 and 1,3,6,8,10,13,16,19-octaazabicyclo(6.6.6)icosane (sepulchrate) 3. Compounds 2 and 3 favour binding of Li+ and Mg2+ and exhibit a cavity size similar to [2.1.1], whereas cryptand 1 has a cavity size similar to [2.2.2] and prefers the selective binding of K+ and Ba2+. The cryptand flexibility of 1 is attributed mainly to the groups adjacent to the bridgehead nitrogens, whereas the main guiding feature for the flexibility of 2 and 3 can be traced back to the coordination of the ethylenediamine spacer.
Synthesis of 5-Aryloxazolidines via 1,3-Dipolar Cycloaddition Reaction of a Non-Stabilized Azomethine Ylide with Aromatic Aldehydes
Authors: Ryan John H. , Spiccia Nadia , Wong Leon S.-M. , Holmes Andrew B.
Published: December 2007

The 1,3-dipolar cycloaddition reaction of a non-stabilized azomethine ylide 4a, formed in situ from N-(methoxymethyl)-N-(trimethylsilylmethyl)benzylamine 5 and a catalytic amount of trifluoroacetic acid, with aromatic aldehydes 3 gives rise to N-benzyl-5-aryloxazolidines 1. Under these conditions, 4-hydroxybenzaldehyde 3p undergoes two-fold addition of azomethine ylide 4a to afford bis adduct 11.
Recruitment of conjugative DNA transfer substrate to
Agrobacterium
type IV secretion apparatus
Authors: Guo Minliang , Jin Shouguang , Sun Deying , Hew Choy L. , Pan Shen Q.
Published: December 2007

Bacterial type IV secretion system (T4SS) belongs to a growing class of evolutionarily conserved transporters that translocate DNA and proteins into a wide variety of organisms including bacterial and eukaryotic cells. Archetypal is the
Agrobacterium tumefaciens
VirB/D4 T4SS that transfers oncogenic T-DNA to various eukaryotic cells, which is transferred as a nucleoprotein T-complex with VirD2 as the pilot protein. As a derivative of plasmid conjugation systems, the VirB/D4 T4SS can also transfer certain mobilizable plasmids and bacterial proteins like VirE2 and VirF, although it is unknown how the membrane-bound T4SS recruits different transfer substrates. Here, we show that a cytoplasmic VirD2-binding protein (VBP) is involved in the recruitment of the T-complex to the energizing components of the T4SS, including VirD4, VirB4, and VirB11. VBP is also important for the recruitment of a conjugative plasmid to a different transfer system independent of VirB/D4. These data indicate that VBP functions as a previously unrecognized recruiting protein that helps couple nucleoprotein substrates to the appropriate transport sites for conjugative DNA transfers. VBP has three functionally redundant homologs, and similar homologs can be found in different bacterial genomes, suggesting a previously uncharacterized class of proteins involved in conjugative DNA transfers.
Structure, inhibitor, and regulatory mechanism of Lyp, a lymphoid-specific tyrosine phosphatase implicated in autoimmune diseases
Authors: Yu Xiao , Sun Jin-Peng , He Yantao , Guo Xiaoling , Liu Sijiu , Zhou Bo , Hudmon Andy , Zhang Zhong-Yin
Published: December 2007

The lymphoid-specific tyrosine phosphatase (Lyp) has generated enormous interest because a single-nucleotide polymorphism in the gene (
PTPN22
) encoding Lyp produces a gain-of-function mutant phosphatase that is associated with several autoimmune diseases, including type I diabetes, rheumatoid arthritis, Graves disease, and systemic lupus erythematosus. Thus, Lyp represents a potential target for a broad spectrum of autoimmune disorders. Unfortunately, no Lyp inhibitor has been reported. In addition, little is known about the structure and biochemical mechanism that directly regulates Lyp function. Here, we report the identification of a bidentate salicylic acid-based Lyp inhibitor I-C11 with excellent cellular efficacy. Structural and mutational analyses indicate that the inhibitor binds both the active site and a nearby peripheral site unique to Lyp, thereby furnishing a solid foundation upon which inhibitors with therapeutic potency and selectivity can be developed. Moreover, a comparison of the apo- and inhibitor-bound Lyp structures reveals that the Lyp-specific region S
35
TKYKADK
42
, which harbors a PKC phosphorylation site, could adopt either a loop or helical conformation. We show that Lyp is phosphorylated exclusively at Ser-35 by PKC both
in vitro
and
in vivo
. We provide evidence that the status of Ser-35 phosphorylation may dictate the conformational state of the insert region and thus Lyp substrate recognition. We demonstrate that Ser-35 phosphorylation impairs Lyp's ability to inactivate the Src family kinases and down-regulate T cell receptor signaling. Our data establish a mechanism by which PKC could attenuate the cellular function of Lyp, thereby augmenting T cell activation.
Antiribosomal-P autoantibodies from psychiatric lupus target a novel neuronal surface protein causing calcium influx and apoptosis
Authors: Matus Soledad , Burgos Patricia V. , Bravo-Zehnder Marcela , Kraft Regine , Porras Omar H. , Farías Paula , Barros L. Felipe , Torrealba Fernando , Massardo Loreto , Jacobelli Sergio , González Alfonso
Published: December 2007

The interesting observation was made 20 years ago that psychotic manifestations in patients with systemic lupus erythematosus are associated with the production of antiribosomal-P protein (anti-P) autoantibodies. Since then, the pathogenic role of anti-P antibodies has attracted considerable attention, giving rise to long-term controversies as evidence has either contradicted or confirmed their clinical association with lupus psychosis. Furthermore, a plausible mechanism supporting an anti-P–mediated neuronal dysfunction is still lacking. We show that anti-P antibodies recognize a new integral membrane protein of the neuronal cell surface. In the brain, this neuronal surface P antigen (NSPA) is preferentially distributed in areas involved in memory, cognition, and emotion. When added to brain cellular cultures, anti-P antibodies caused a rapid and sustained increase in calcium influx in neurons, resulting in apoptotic cell death. In contrast, astrocytes, which do not express NSPA, were not affected. Injection of anti-P antibodies into the brain of living rats also triggered neuronal death by apoptosis. These results demonstrate a neuropathogenic potential of anti-P antibodies and contribute a mechanistic basis for psychiatric lupus. They also provide a molecular target for future exploration of this and other psychiatric diseases.
Flaubert, Ethics and Queer Religious Art: ‘La Légende de saint Julien L'Hospitalier’
Authors: Hartford Jason
Published: December 2007

‘La Légende de saint Julien l'Hospitalier’, from Flaubert's
Trois Contes
, engages harmoniously with Christianity while remaining independent of it. It reconciles the amoral demands of the writer's ‘language-project’ with his equally strong ethical commitments. Flaubert found a symbolic and metaphorical foil for reconciling this unlikely pairing of ideals by queering the figure of St Julien, in the senses both of associating him with minority sexuality, and of rendering strange the representational process of which he is the centre. In doing this the story incorporates an audacious approach to visual as well as literary sources, particularly the figure of the devil in the stained glass window at Rouen cathedral. This discussion elucidates these topics through re-examining crucial moments from the tale, especially its ending, with comparative reference to
Madame Bovary
. It pursues such topics as scandal, the iconic, irony and atheism — always with reference to Flaubert's representational project, and his recognition of a moral ideal in the concept of hospitality.
Association between folate‐metabolizing pathway polymorphism and non‐Hodgkin lymphoma
Authors: Kim Hee Nam , Lee Il‐Kwon , Kim Yeo‐Kyeoung , Tran Huong Thi Thanh , Yang Deok‐Hwan , Lee Je‐Jung , Shin Min–Ho , Park Kyeong‐Soo , Shin Myung‐Geun , Choi Jin‐Su , Kim Hyeoung‐Joon
Published: December 2007

Polymorphisms in the genes coding folate‐metabolizing enzymes affect the risk of some forms of cancer. We investigated the association between these polymorphisms and non‐Hodgkin lymphoma (NHL) risk in a population‐based study (583 cases and 1700 controls). The MTHFR 677TT and CT genotypes were associated with reduced risk for NHL [odds ratios (OR) = 0·79; 95% confidence intervals (CI) = 0·65–0·98 for 677CT and 0·61; 0·45–0·82 for 677TT] and diffuse large B‐cell lymphoma (DLBCL) (OR = 0·68; 0·51–0·88 for 677CT; OR = 0·56; 0·38–0·83 for 677TT). The MTHFR 1298CC genotype was associated with increased risk for NHL (OR = 1·71; 1·07–2·75) and T‐cell lymphoma (OR = 3·05; 1·53‐6·11). The MTRR 66GG genotype was associated with increased risk for DLBCL (OR = 1·56; 1·03‐2·38) and the TYMS 2R2R genotype was associated with increased risk for T‐cell lymphoma (OR = 2·83; 1·33–6·01). Using subjects with 3RG3RG as a reference group, TYMS 2R2R was associated with increased risk for T‐cell lymphoma (OR = 2·46; 1·04–5·79). Interestingly, we observed a reduced association between the TYMS 2R3RG genotype and DLBCL (OR = 0·61; 0·38–0·99). These results suggest that MTHFR, MTRR and TYMS polymorphisms may play a significant role in the risk for NHL.
The value of georeferenced collection records for predicting patterns of mosquito species richness and endemism in the Neotropics
Authors: FOLEY DESMOND H. , WEITZMAN ANNA L. , MILLER SCOTT E. , FARAN MICHAEL E. , RUEDA LEOPOLDO M. , WILKERSON RICHARD C.
Published: December 2007

Abstract 1. Determining large‐scale distribution patterns for mosquitoes could advance knowledge of global mosquito biogeography and inform decisions about where mosquito inventory needs are greatest.

2. Over 43 000 georeferenced records are presented of identified and vouchered mosquitoes from collections undertaken between 1899 and 1982, from 1853 locations in 42 countries throughout the Neotropics. Of 492 species in the data set, 23% were only recorded from one location, and Anopheles albimanus Wiedemann is the most common species.

3. A linear log–log species–area relationship was found for mosquito species number and country area. Chile had the lowest relative density of species and Trinidad‐Tobago the highest, followed by Panama and French Guiana.

4. The potential distribution of species was predicted using an Ecological Niche Modelling (ENM) approach. Anopheles species had the largest predicted species ranges, whereas species of Deinocerites and Wyeomyia had the smallest.

5. Species richness was estimated for 1° grids and by summing predicted presence of species from ENM. These methods both showed areas of high species richness in French Guiana, Panama, Trinidad‐Tobago, and Colombia. Potential hotspots in endemicity included unsampled areas in Panama, French Guiana, Colombia, Belize, Venezuela, and Brazil.

6. Argentina, The Bahamas, Bermuda, Bolivia, Cuba, and Peru were the most under‐represented countries in the database compared with known country species occurrence data. Analysis of species accumulation curves suggested patchiness in the distribution of data points, which may affect estimates of species richness.

7. The data set is a first step towards the development of a global‐scale repository of georeferenced mosquito collection records.
Heat stress induces alkaline phosphatase activity and heat shock protein 25 expression in cultured pulp cells
Authors: Lee M.‐W. , Muramatsu T. , Uekusa T. , Lee J.‐H. , Shimono M.
Published: December 2007

Aim  To investigate the responses of cultured rat pulp cells to heat stress.

Methodology  Pulp cells were obtained from rat incisors and cultured at 37 °C. The cells were cultured at 42 °C for 30 min and then cultured at 37 °C again. Morphology, alkaline phosphatase (ALP) activity and expression of heat shock protein 25 (HSP25) were investigated at 0, 1, 3, 5, 7, 10 and 14 days following stimulation. As a control, the cells were maintained at 37 °C.

Results  Although there were few cells of apoptosis immediately after heat stress, there were mitotic cells from day 1 after heat stress. ALP activity in the heat stress group significantly increased at days 7 and 14 compared with the control group (about 1.7‐fold, P < 0.01, Friedman test). HSP25 expression increased in both groups, with HSP25 in the heat stress group being expressed earlier than in the control group, and nuclear localization of HSP25 was observed at days 0 and 1 in heat‐stressed cells.

Conclusion  These results suggest that heat stress not only induces HSP25 but also enhances ALP activity in pulp cells.
FSH and bFGF stimulate the production of glutathione in cultured rat Sertoli cells
Authors: Gualtieri Ariel F. , Mazzone Graciela L. , Rey Rodolfo A. , Schteingart Helena F.
Published: December 2007

Migration of developing germ cells from the basal to the adluminal compartment of the seminiferous epithelium requires extensive tissue restructuring, resulting in the production of reactive oxygen species. Sertoli cells are involved in this process. Glutathione (GSH), produced by Sertoli cells, has an essential role in cell protection against oxidative stress. Intracellular GSH content is maintained by de novo synthesis, involving glutamate‐cysteine ligase catalytic (GCLC) and modulatory (GCLM) subunits, and by recycling from oxidized GSH, catalysed by glutathione reductase (GR). To assess whether follicle‐stimulating hormone (FSH) and basic fibroblast growth factor (bFGF) modulate GSH production in Sertoli cells by regulating the expression of GCLC, GCLM and/or GR, we performed in vitro studies using rat Sertoli cells in primary culture. FSH and bFGF stimulation increased Sertoli cell GSH levels after 24 h incubation. The simultaneous addition of FSH and bFGF did not produce any further effect. GCLM expression was upregulated by FSH and bFGF 6 h. At 24 h, only the FSH‐mediated effect was still observed. FSH and bFGF also upregulated GR expression. In conclusion, our results show that FSH and bFGF increase GSH levels in Sertoli cells through stimulation of the de novo synthesis and recycling by upregulating GCLM and GR expression respectively. Therefore, protection of germ cells against oxidative stress seems to be regulated by hormones and germ cell‐released growth factors capable of influencing the production of Sertoli cell GSH.
Hypergonadotropic hypogonadism in a patient with inv ins (2;4)
Authors: Tzschach A. , Ramel C. , Kron A. , Seipel B. , Wüster C. , Cordes U. , Liehr T. , Hoeltzenbein M. , Menzel C. , Ropers H.‐H. , Ullmann R. , Kalscheuer V. , Decker J. , Steinberger D.
Published: December 2007

We report on a 30‐year‐old man with azoospermia, primary hypogonadism and minor dysmorphic features who carried a balanced insertional chromosome translocation inv ins (2p24;4q28.3q31.22)de novo. Molecular cytogenetic analyses of the chromosome breakpoints revealed the localization of the breakpoint in 4q28.3 between BACs RP11‐143E9 and RP11‐285A15, an interval that harbours the PCDH10 gene. In 4q31.22, a breakpoint‐spanning clone (RP11‐6L6) was identified which contains the genes LSM6 and SLC10A7. On chromosome 2, BACs RP11‐531P14 and RP11‐360O18 flank the breakpoint in 2p24, a region void of known genes. In conclusion, the chromosome aberration of this patient suggests a gene locus for primary hypogonadism in 2p24, 4q28.3 or 4q31.2, and three possible candidate genes (LSM6, SLC10A7 and PCDH10) were identified by breakpoint analyses.
Sensory evaluation of probiotic Minas fresh cheese with Lactobacillus acidophilus added solely or in co‐culture with a thermophilic starter culture
Authors: De Souza Cínthia H. B. , Buriti Flávia C. A. , Behrens Jorge H. , Saad Susana M. I.
Published: December 2007

Sensory acceptance of formulations of probiotic Minas fresh cheese was investigated. Cheeses were prepared and supplemented with Lactobacillus acidophilus (T1 – probiotic), Lactobacillus acidophilus + Streptococcus thermophilus (T2 – probiotic + starter) or produced with no addition of cultures (T3 – control). Sensory acceptance tests were performed after 7 and 14 days of storage at 5 °C, using a 9‐point hedonic scale (1 = dislike extremely; 9 = like extremely). After 7 days, no significant difference was detected among cheeses T1, T2 and T3 (P > 0.05). After 14 days, cheeses T1 and T2 presented higher acceptance and differed significantly from cheeses T3. Cheeses T3 presented significant difference between 7 and 14 days of storage (P < 0.05), whereas probiotic cheeses T1 and T2 were stable in the same period (P > 0.05). The addition of L. acidophilus, either solely or in co‐culture with a thermophilic starter culture, resulted in good acceptance of Minas fresh cheese, improving sensory performance of the product during storage.
Analytical TEM study of annealed nanocrystalline cobalt–phosphorous electrodeposits
Authors: DA SILVA M. , KLEMENT U.
Published: December 2007

Investigation of thermal stability of two nanocrystalline Co–P alloys shows that P atoms segregate to the grain boundaries upon annealing until precipitation of Co2P and CoP precipitates takes place. The P‐rich precipitates formed have been investigated by analytical transmission electron microscopy to obtain statistical results of precipitate size, volume fraction and spatial distribution. Electron spectroscopic imaging maps show that the P‐rich precipitates are 33 ± 9 nm in Co–1.1at.%P and 33 ± 12 nm in Co–3.2at.%P. The main differences between the alloys are the precipitate size distribution (Co–3.2at.%P having broader distribution) and precipitate volume number density (Co–3.2at.%P has 1.8 times more precipitates than Co–1.1at.%P). The volume fraction of precipitates is 3.0% in Co–1.1at.%P and 4.4% in Co–1.1at.%P. Most of the precipitates are of nearly spherical or slightly elongated shape, and only a few have a platelet‐like shape as expected from previous tomographic atom probe measurements. Due to the truncation and projection effects, the composition of the precipitates could not be determined.
Evaluation of intragranular misorientation parameters measured by EBSD in a hot worked austenitic stainless steel
Authors: JORGE‐BADIOLA D. , IZA‐MENDIA A. , GUTIÉRREZ I.
Published: December 2007

An extensive characterization of hot deformed austenitic stainless steel was carried out using the electron backscatter diffraction technique. Special emphasis was given to the misorientation parameters related to different length scales. These parameters show a behaviour that is sensitive to the amount of applied strain and also lead to increasing values for both the strain and the scale length.

At the same time, the use of different thresholds and scan steps in the evaluation of the parameters were analyzed in order to assess the validity of the results.
Morphological analyses of minute crystals by using stereo‐photogrammetric scanning electron microscopy and electron back‐scattered diffraction
Authors: KAMEDA JUN , INOGUCHI RYOICHI , PRIOR DAVID J. , KOGURE TOSHIHIRO
Published: December 2007

We present a new method for the morphological analyses of minute faceted crystals by combining stereo‐photogrammetric analysis of scanning electron microscope images and electron back‐scattered diffraction. Two scanning electron microscope images of the same crystal, recorded at different tilt angles of the specimen stage, are used to determine the orientations of crystal edges in a specimen‐fixed coordinate system. The edge orientations are converted to the indices [uvw] in the crystal system using the crystal orientation determined by electron back‐scattered diffraction analysis. The Miller indices of crystal facets are derived from the indices of the edges surrounding the facets. The method is applicable to very small crystal facets. The angular error, as derived from tests using a calcite crystal of known morphology, is a few degrees.

To demonstrate the applicability of the method, the morphology of boehmite (γ‐AlOOH) precipitated from solution during the dissolution of anorthite was analyzed. The micrometre‐sized boehmite crystals are surrounded by two {010} basal facets and eight equivalent side facets that can be indexed equally well as {323}, {434} or {545}. We suggest that these side facets are in fact {111}, the morphology having been modified slightly (by a few degrees) by a small extension associated with opening along (010) microcleavage planes. Tiny {140} facets are also commonly observed.
Modular software platform for low‐dose electron microscopy and tomography
Authors: MARSH MICHAEL P. , CHANG JUAN T. , BOOTH CHRISTOPHER R. , LIANG NATHAN L. , SCHMID MICHAEL F. , CHIU WAH
Published: December 2007

Transmission electron microscopy imaging protocols required by structural scientists vary widely and can be laborious without tailor‐made applications. We present here the jeol automated microscopy expert system (james) api integrator, a programming library for computer control of transmission electron microscopy operations and equipment. james has been implemented on JEOL microscopes with Gatan CCDs but is designed to be modular so it can be adapted to run on different microscopes and detectors. We have used the james api integrator to develop two applications for low‐dose digital imaging: james imaging application and the mr t tomographic imaging application. Both applications have been widely used within our NCRR‐supported Center for routine data collection and are now made available for public download.
Linking Millennium Cohort data to birth registration and hospital episode records
Authors: Hockley Christine , Quigley Maria A. , Hughes Gareth , Calderwood Lisa , Joshi Heather , Davidson Leslie L.
Published: December 2007

The Millennium Cohort Study of 18 818 UK babies born in 2000–02 interviewed parents when the baby was 9 months old. Time constraints on the interview limited the amount of health‐related questions that could be included. The aim of this study was to augment interview data with information from birth registrations and hospital records. It also provided an opportunity to assess the accuracy of the data acquired and parents' recall of the information on pregnancy and delivery. Deterministic and probabilistic matching were used to obtain information from birth registration and hospital records. Investigation into the accuracy of the matches obtained was undertaken. The records received were checked for range, consistency and completion.

Birth registration data were obtained for 99% of those who gave consent. The number of additional variables gained ranged from six in Northern Ireland to 16 in Scotland. Hospital record data were obtained for 83% of those who gave consent. The additional general and maternity‐related variables gained ranged from 55 in Scotland to 76 in England. Completion of available health record variables ranged from 28% to 100% across all UK countries. Linkage to birth registration and hospital records in order to augment Millennium Cohort Study data with routinely collected data was successful. The variables gained by linkage have added considerable value to the cohort study and validated some of the mother's responses.