bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved model for window breakdown at low pressure
Authors: Chang C. , Liu G. Z. , Zhu X. X. , Chen H. B. , Fang J. Y.
Published: March 2009

An improved global model is proposed to analyze high power microwave dielectric window breakdown at low pressure. The effect of ionization on the average momentum and energy of electrons is taken into account and a Maxwellian electron energy distribution function is adopted. The plasma energy flow and density loss to dielectric, and partially secondary electrons returning plasma to compensate the density loss, have been analytically considered. Space charge potential drop and the generalized Bohm criterion are deduced analytically. After considering the energy and density loss as well as the secondary electron compensation, the breakdown time by using numerical calculation under low pressure gets shorter compared with that under no wall loss condition. In other words, the dielectric surface breakdown time is lower than plasma volume breakdown time.
Ab initio simulation of the equation of state and kinetics of shocked water
Authors: Goldman Nir , Reed Evan J. , Kuo I.-F. William , Fried Laurence E. , Mundy Christopher J. , Curioni Alessandro
Published: March 2009

We report herein first principles simulations of water under shock loading and the chemical reactivity under these hot, compressed conditions. Using a recently developed simulation technique for shock compression, we observe that water achieves chemical equilibrium in less than 2 ps for all shock conditions studied. We make comparison to the experimental results for the Hugoniot pressure and density final states. Our simulations show that decomposition occurs through the reversible reaction H2O↔H++OH−, in agreement with experiment. Near the approximate intersection of the Hugoniot and the Neptune isentrope, we observe high concentrations of charged species that contribute electronic states near the band gap.
Dynamical symmetries of the Klein–Gordon equation
Authors: Zhang Fu-Lin , Chen Jing-Ling
Published: March 2009

The dynamical symmetries of the two-dimensional Klein–Gordon equations with equal scalar and vector potentials (ESVPs) are studied. The dynamical symmetries are considered in the plane and the sphere, respectively. The generators of the SO(3) group corresponding to the Coulomb potential and the SU(2) group corresponding to the harmonic oscillator potential are derived. Moreover, the generators in the sphere construct the Higgs algebra. With the help of the Casimir operators, the energy levels of the Klein–Gordon systems are yielded naturally.
Unusual dynamical arrest in polymer grafted nanoparticles
Authors: Kandar A. K. , Srivastava S. , Basu J. K. , Mukhopadhyay M. K. , Seifert S. , Narayanan S.
Published: March 2009

We present results of temperature dependent measurements of dynamics of polymer grafted nanoparticles with high grafting density with star polymerlike morphology. We observed for the low grafting density and hence low functionality sample, a dynamically arrested state with lowering of temperature, similar to what was conjectured earlier. However the high grafting density sample shows liquidlike relaxation at all measured temperatures. Possible origin of dynamical arrest in the two grafting density sample is discussed.
Concentration fluctuations and microheterogeneity in aqueous amide mixtures
Authors: Zoranić Larisa , Mazighi Redha , Sokolić Franjo , Perera Aurélien
Published: March 2009

The relationship between concentration fluctuations and the microheterogeneous status of aqueous amide mixtures is addressed through the molecular dynamics study of three different amides, namely, formamide, N-methylformamide, and dimethylformamide. The computer simulations provide structural evidence that these mixtures exhibit considerable microheterogeneity, in apparent contrast to the experimentally obtained Kirkwood–Buff integrals which indicate that these mixtures should be near ideal. This contradiction is addressed by distinguishing microheterogeneity from concentration fluctuations. The former is the result of mixing H-bonding species under specific constraints due to various bonding possibilities between the molecules, while the second is related to the average relative distribution of the molecules. The relationship between these two different quantities is analyzed and illustrated in terms of the partial site-site structure factors. Small wave-number prepeaks relate to the microheterogeneity while zero wave-number value relates to the concentration fluctuations. A simple analytical statistical model for the microheterogeneity is formulated, which allows to discuss the small wave-number behavior of these structure factors in terms of the kinetics of the transient cluster formation, as observed in the computer simulations.
Charge asymmetry in pure vibrational states of the HD molecule
Authors: Bubin Sergiy , Leonarski Filip , Stanke Monika , Adamowicz Ludwik
Published: March 2009

Very accurate variational calculations of all rotationless states (also called pure vibrational states) of the HD molecule have been performed within the framework that does not assume the Born–Oppenheimer (BO) approximation. The non-BO wave functions of the states describing the internal motion of the proton, the deuteron, and the two electrons were expanded in terms of one-center explicitly correlated Gaussian functions multiplied by even powers of the internuclear distance. Up to 6000 functions were used for each state. Both linear and nonlinear parameters of the wave functions of all 18 states were optimized with a procedure that employs the analytical gradient of the energy with respect to the nonlinear parameters of the Gaussians. These wave functions were used to calculate expectation values of the interparticle distances and some other related quantities. The results allow elucidation of the charge asymmetry in HD as a function of the vibrational excitation.
Identification of the protein folding transition state from molecular dynamics trajectories
Authors: Muff S. , Caflisch A.
Published: March 2009

The rate of protein folding is governed by the transition state so that a detailed characterization of its structure is essential for understanding the folding process. In vitro experiments have provided a coarse-grained description of the folding transition state ensemble (TSE) of small proteins. Atomistic details could be obtained by molecular dynamics (MD) simulations but it is not straightforward to extract the TSE directly from the MD trajectories, even for small peptides. Here, the structures in the TSE are isolated by the cut-based free-energy profile (cFEP) using the network whose nodes and links are configurations sampled by MD and direct transitions among them, respectively. The cFEP is a barrier-preserving projection that does not require arbitrarily chosen progress variables. First, a simple two-dimensional free-energy surface is used to illustrate the successful determination of the TSE by the cFEP approach and to explain the difficulty in defining boundary conditions of the Markov state model for an entropically stabilized free-energy minimum. The cFEP is then used to extract the TSE of a β-sheet peptide with a complex free-energy surface containing multiple basins and an entropic region. In contrast, Markov state models with boundary conditions defined by projected variables and conventional histogram-based free-energy profiles are not able to identify the TSE of the β-sheet peptide.
Laser induced thermal-wave fields in bilayered spherical solids
Authors: Xie Guangxi , Chen Zhifeng , Wang Chinhua , Mandelis Andreas
Published: March 2009

We present a theoretical model for evaluating solid bilayered spherical samples (surfaces) that are heated by a frequency modulated light beam generating thermal waves. The Green’s function method is used as it provides a way of evaluating thermal-wave fields of bilayered spherical structures with arbitrary intensity distributions of incident laser beams. The specific thermal-wave Green’s function corresponding to the composite structure has been derived. The characteristics of the thermal-wave field with respect to the thermal diffusivity of the material, the diameter of the sample, the size of the incident beam, and the polar angle at which the thermal-wave field is measured on the surface are presented. Experimental results obtained with laser infrared photothermal radiometry are fitted to the theory and the thermal diffusivities of steel spheres are deduced.
Development of a compact x-ray particle image velocimetry for measuring opaque flows
Authors: Lee Sang Joon , Kim Guk Bae , Yim Dae Hyun , Jung Sung Yong
Published: March 2009

A compact x-ray particle image velocimetry (PIV) system employing a medical x-ray tube as a light source was developed to measure quantitative velocity field information of opaque flows. The x-ray PIV system consists of a medical x-ray tube, an x-ray charge coupled device camera, a programmable shutter for a pulse-type x ray, and a synchronization device. Through performance tests, the feasibility of the developed x-ray PIV system as a flow measuring device was verified. To check the feasibility of the developed system, we tested a tube flow at two different mean velocities of 1 and 2 mm/s. The x-ray absorption of tracer particles must be quite different from that of working fluid to have a good contrast in x-ray images. All experiments were performed under atmospheric pressure condition. This system is unique and useful for investigating various opaque flows or flows inside opaque conduits.
Effect of nanocrystallinity on the electrochemical performance of LiMn2O4 cathode
Authors: Singhal Rahul , Resto Oscar , Katiyar Ram S.
Published: March 2009

In the present work, we have synthesized nanocrystalline LiMn2O4 of different grain sizes, for application to Li ion rechargeable batteries. LiMn2O4 cathode powder was synthesized by sol-gel method and was high-energy ball milled for 8 and 16h, respectively. The particle sizes of pure, 8h, and 16h ball-milled samples were determined from TEM and measured as ∼225, 40, and 10nm, respectively. The initial discharge capacity of the pure LiMn2O4 cathode material was found to be about 128.75mAh∕g, which was found to decrease on reducing the particle size.
Planar metamaterial with transmission and reflection that depend on the direction of incidence
Authors: Plum E. , Fedotov V. A. , Zheludev N. I.
Published: March 2009

We report that normal incidence reflection and transmission of circularly polarized electromagnetic waves from and through planar split-ring microwave metamaterials with chiral symmetry breaking depends on the incidence direction and handedness of circular polarization. The effect has a resonant nature and is linked to the lack of mirror symmetry in the metamaterial pattern leading to a polarization-sensitive excitation of electric and magnetic dipolar responses in the meta-molecules. It has striking phenomenological resemblance with the reflective circular dichroism of high-temperature “anyon” superconductors.
Effect of alignment on the nematic to isotropic phase transition of bulk octylcyanobiphenyl brings possible solutions to liquid crystal display drawback
Authors: Sharma Dipti
Published: March 2009

The effect of alignment on the nematic to isotropic phase transition of bulk octylcyanobiphenyl reveals a reduced time and temperature lag with possible solutions to the time response and backlight bleed drawbacks of liquid crystal displays (LCDs). The aligned octylcyanobiphenyl shows a quicker and early occurrence of the nematic transition with less deviation from thermal rates than the unaligned octylcyanobiphenyl using calorimetry technique. Smaller enthalpy of activation indicates less energy requirement and makes the aligned octylcyanobiphenyl suitable for LCDs. The results are discussed in terms of the formation of aligned domains of octylcyanobiphenyl molecules under the force of magnetic field.
Exotic spin textures show up in diverse materials
Authors: Day Charles
Published: March 2009

A binary semiconductor, an insulating alloy, and a bulk ferromagnet can each be coaxed into manifesting new and different forms of spin coherence.
Mechanism of fission
Authors: Wheeler John A.
Published: March 2009

On a morning walk across the snowy Princeton campus early in 1939, Niels Bohr suddenly understood that the rare isotope uranium-235 was alone responsible for the recently discovered nuclear fission.
Organic acid mediated nutrient extraction efficiency in three calcareous soils
Authors: Khademi Z. , Jones D. L. , Malakouti M. J. , Asadi F. , Ardebili M.
Published: March 2009

This study was conducted to evaluate the effects of organic acids on the concentrations of metals and anions in soil solution. Three soils with contrasting CaCO3 contents were extracted with organic acid solutions (citrate and oxalate) of different concentrations for different time periods and analysed for Fe, Mn, Zn, Cu, P, and Ca. The soils showed a significant change after the addition of the organic acids to the soil. The mobilisation of metals from the solid phase was dependent on concentration and ionic form of organic acid. High concentrations of citric acid were more effective than oxalate in mobilising Ca, Fe, Mn, and Zn. Overall; oxalate was slightly more effective than citrate in mobilising P. Generally, the higher the organic acid concentration of the extractant solution, the greater was the amount of elements extracted from the soil. Citrate tended to be more effective than oxalate at mobilising elements from the soil. All pH changes were dependent on organic acid concentration.
Cooperation and virulence of clinical
Pseudomonas aeruginosa
populations
Authors: Köhler Thilo , Buckling Angus , van Delden Christian
Published: March 2009

Bacteria communicate and cooperate to perform a wide range of social behaviors including production of extracellular products (public goods) that are crucial for growth and virulence. Their expression may be switched on by the detection of threshold densities of diffusible signals [Quorum-Sensing (QS)]. Studies using the opportunistic pathogen
Pseudomonas aeruginosa
suggest that QS “cheats”—individuals that don't respond to the QS signal, but are still able to use public goods produced by others—have a selective advantage in the presence of QS cooperators. It is, however, unclear whether this type of social exploitation is relevant in clinical contexts. Here, we report the evolutionary dynamics and virulence of
P. aeruginosa
populations during lung colonization of mechanically ventilated patients in the absence of antimicrobial treatments. We observed a large diversity of QS phenotypes among initial colonizing isolates. This diversity decreased over a matter of days, concomitant with a gradual increase in the proportion of QS cheating mutants (
lasR
mutants), which were found in 80% of the patients after 9 days of colonization. These mutants often evolved from initial wild-type genotypes. The fitness advantage of the
lasR
mutants is almost certainly due to social exploitation, because this advantage was only apparent in the presence of QS wild-type cells. Crucially, ventilator-associated pneumonia occurred significantly earlier in patients predominantly colonized by QS wild-type populations, highlighting the importance of QS in this clinical situation. These results demonstrate that social interactions can shape the short-term evolution and virulence of bacterial pathogens in humans, providing novel opportunities for therapy.
Scaleable manufacture of HIV-1 entry inhibitor griffithsin and validation of its safety and efficacy as a topical microbicide component
Authors: O'Keefe Barry R. , Vojdani Fakhrieh , Buffa Viviana , Shattock Robin J. , Montefiori David C. , Bakke James , Mirsalis Jon , d'Andrea Anna-Lisa , Hume Steven D. , Bratcher Barry , Saucedo Carrie J. , McMahon James B. , Pogue Gregory P. , Palmer Kenneth E.
Published: March 2009

To prevent sexually transmitted HIV, the most desirable active ingredients of microbicides are antiretrovirals (ARVs) that directly target viral entry and avert infection at mucosal surfaces. However, most promising ARV entry inhibitors are biologicals, which are costly to manufacture and deliver to resource-poor areas where effective microbicides are urgently needed. Here, we report a manufacturing breakthrough for griffithsin (GRFT), one of the most potent HIV entry inhibitors. This red algal protein was produced in multigram quantities after extraction from
Nicotiana benthamiana
plants transduced with a tobacco mosaic virus vector expressing GRFT. Plant-produced GRFT (GRFT-P) was shown as active against HIV at picomolar concentrations, directly virucidal via binding to HIV envelope glycoproteins, and capable of blocking cell-to-cell HIV transmission. GRFT-P has broad-spectrum activity against HIV clades A, B, and C, with utility as a microbicide component for HIV prevention in established epidemics in sub-Saharan Africa, South Asia, China, and the industrialized West. Cognizant of the imperative that microbicides not induce epithelial damage or inflammatory responses, we also show that GRFT-P is nonirritating and noninflammatory in human cervical explants and in vivo in the rabbit vaginal irritation model. Moreover, GRFT-P is potently active in preventing infection of cervical explants by HIV-1 and has no mitogenic activity on cultured human lymphocytes.
Interaction of phosphodiesterase 3A with brefeldin A-inhibited guanine nucleotide-exchange proteins BIG1 and BIG2 and effect on ARF1 activity
Authors: Puxeddu Ermanno , Uhart Marina , Li Chun-Chun , Ahmad Faiyaz , Pacheco-Rodriguez Gustavo , Manganiello Vincent C. , Moss Joel , Vaughan Martha
Published: March 2009

ADP-ribosylation factors (ARFs) have crucial roles in vesicular trafficking. Brefeldin A-inhibited guanine nucleotide-exchange proteins (BIG)1 and BIG2 catalyze the activation of class I ARFs by accelerating replacement of bound GDP with GTP. Several additional and differing actions of BIG1 and BIG2 have been described. These include the presence in BIG2 of 3 A kinase-anchoring protein (AKAP) domains, one of which is identical in BIG1. Proteins that contain AKAP sequences act as scaffolds for the assembly of PKA with other enzymes, substrates, and regulators in complexes that constitute molecular machines for the reception, transduction, and integration of signals from cAMP or other sources, which are initiated, propagated, and transmitted by chemical, electrical, or mechanical means. Specific depletion of HeLa cell PDE3A with small interfering RNA significantly decreased membrane-associated BIG1 and BIG2, which by confocal immunofluorescence microscopy were widely dispersed from an initial perinuclear Golgi concentration. Concurrently, activated ARF1-GTP was significantly decreased. Selective inhibition of PDE3A by 1-h incubation of cells with cilostamide similarly decreased membrane-associated BIG1. We suggest that decreasing PDE3A allowed cAMP to accumulate in microdomains where its enzymatic activity limited cAMP concentration. There, cAMP-activated PKA phosphorylated BIG1 and BIG2 (AKAPs for assembly of PKA, PDE3A, and other molecules), which decreased their GEP activity and thereby amounts of activated ARF1-GTP. Thus, PDE3A in these BIG1 and BIG2 AKAP complexes may contribute to the regulation of ARF function via limitation of cAMP effects with spatial and temporal specificity.
Contrasting models in literacy practice among heritage language learners of Mandarin
Authors: Li Jia
Published: March 2009

This paper examines how the development of print literacy practices was approached at a Chinese heritage language school in the Southwest of the United States. More specifically, it investigates the roles of instructors and parents in the development of literacy among heritage language learners of Mandarin. The study explores two contrasting approaches to literacy instruction which occurred in both the classrooms and homes of the learners, where many literacy activities took place. The findings indicate that the learners’ literacy development was determined by many factors, such as the instructors’ and the parents’ own learning experiences, their perspectives on literacy, and the approaches they adopted in both classroom and home settings. The study also reveals that instructors and parents conceptualized an important link between socializing the learners into traditional Chinese values and the promotion of their literacy development.
Effects of phonological awareness training on reading achievement
Authors: Treutlein Anke , Zöller Isabelle , Roos Jeanette , Schöler Hermann
Published: March 2009

Phonological awareness is usually considered to be an important prerequisite for success in literacy acquisition. Children who had phonological awareness training in preschool not only show a better performance in phonological awareness tasks at elementary school but also perform better in reading and writing than untrained children. As part of the EVES longitudinal study, reading and spelling skills of 1520 children who entered school in the fall of 2001 and 2002 were assessed throughout elementary school. The comparison of a matched sample of 107 trained with 107 untrained children shows that untrained children are outperformed by trained children in reading. The best training effects can be found with girls while boys seem to profit from the intervention only towards the end of elementary school. Training phonological awareness in preschool thus facilitates reading acquisition, even if there are other important influencing factors (e.g. class context).
Ferric reductase A is essential for effective iron acquisition in Paracoccus denitrificans
Authors: Sedláček Vojtěch , van Spanning Rob J. M. , Kučera Igor
Published: March 2009

Based on N-terminal sequences obtained from the purified cytoplasmic ferric reductases FerA and FerB, their corresponding genes were identified in the published genome sequence ofParacoccus denitrificansPd1222. TheferAandferBgenes were cloned and individually inactivated by insertion of a kanamycin resistance marker, and then returned toP. denitrificansfor exchange with their wild-type copies. The resultingferAandferBmutant strains showed normal growth in brain heart infusion broth. Unlike theferBmutant, the strain lacking FerA did not grow on succinate minimal medium with ferric 2,3-dihydroxybenzoate as the iron source, and grew only poorly in the presence of ferric sulfate, chloride, citrate, NTA, EDTA and EGTA. Moreover, theferAmutant strain was unable to produce catechols, which are normally detectable in supernatants from iron-limited wild-type cultures. Complementation of theferAmutation using a derivative of the conjugative broad-host-range plasmid pEG400 that contained the wholeferAgene and its putative promoter region largely restored the wild-type phenotype. Partial, though significant, restoration could also be achieved with 1 mM chorismate added to the growth medium. The purified FerA protein acted as an NADH : FMN oxidoreductase and catalysed the FMN-mediated reductive release of iron from the ferric complex of parabactin, the major catecholate siderophore ofP. denitrificans. The deduced amino acid sequence of the FerA protein has closest similarity to flavin reductases that form part of the flavin-dependent two-component monooxygenases. Taken together, our results demonstrate an essential role of reduced flavins in the utilization of exogenous ferric iron. These flavins not only provide the electrons for Fe(III) reduction but most probably also affect the rate of siderophore production.
Diffusion‐limited binding explains binary dose response for local arterial and tumour drug delivery
Authors: Tzafriri A. R. , Levin A. D. , Edelman E. R.
Published: March 2009

Background:  Local drug delivery has transformed medicine, yet it remains unclear how drug efficacy depends on physicochemical properties and delivery kinetics. Most therapies seek to prolong release, yet recent studies demonstrate sustained clinical benefit following local bolus endovascular delivery.

Objectives:  The purpose of the current study was to examine interplay between drug dose, diffusion and binding in determining tissue penetration and effect.

Methods:  We introduce a quantitative framework that balances dose, saturable binding and diffusion, and measured the specific binding parameters of drugs to target tissues.

Results:  Model reduction techniques augmented by numerical simulations revealed that impact of saturable binding on drug transport and retention is determined by the magnitude of a binding potential, Bp, ratio of binding capacity to product of equilibrium dissociation constant and accessible tissue volume fraction. At low Bp (< 1), drugs are predominantly free and transport scales linearly with concentration. At high Bp (> 40), drug transport exhibits threshold dependence on applied surface concentration.

Conclusions:  In this paradigm, drugs and antibodies with large Bp penetrate faster and deeper into tissues when presented at high concentrations. Threshold dependence of tissue transport on applied surface concentration of paclitaxel and rapamycin may explain threshold dose dependence of in vivo biological efficacy of these drugs.
Wolbachia induces strong cytoplasmic incompatibility in the predatory bug Macrolophus pygmaeus
Authors: Machtelinckx T. , Van Leeuwen T. , Vanholme B. , Gehesquière B. , Dermauw W. , Vandekerkhove B. , Gheysen G. , De Clercq P.
Published: March 2009

Macrolophus pygmaeus is a heteropteran predator that is widely used in European glasshouses for the biological control of whiteflies, aphids, thrips and spider mites. We have demonstrated that the insect is infected with the endosymbiotic bacterium Wolbachia pipientis. Several gene fragments of the endosymbiont were sequenced and subsequently used for phylogenetic analysis, revealing that it belongs to the Wolbachia supergroup B. The endosymbiont was visualized within the ovarioles using immunolocalization. Tetracycline treatments were used to cure M. pygmaeus from its infection. Although a completely cured line could not be obtained by this approach, the application of a constant antibiotic pressure over 13 generations resulted in a line with a significantly reduced Wolbachia concentration. Crosses performed with this tetracycline‐treated line revealed that the endosymbiont causes severe cytoplasmic incompatibility. This is the first report of a reproductive effect induced by Wolbachia in an economically important heteropteran predator that may have vital implications for its commercial production and use in biological control.
Irritable bowel syndrome in childhood: visceral hypersensitivity and psychosocial aspects
Authors: Iovino P. , Tremolaterra F. , Boccia G. , Miele E. , Ruju F. M. , Staiano A.
Published: March 2009

Abstract  Visceral hypersensitivity is often considered to play a major etiologic role in the pathophysiology of irritable bowel syndrome in adults, and some authors argue that this increased sensitivity is mainly due to psychological factors. In contrast, there are no data in children with irritable bowel syndrome which confirm this relationship. The aim of the study was to evaluate the relationship between psychosocial aspects and sensorymotor function in children affected by irritable bowel syndrome. Ten children fulfilling the Rome II criteria for irritable bowel syndrome and seven healthy controls were enrolled. We studied the thresholds and the perception of visceral stimuli in the rectum by means of an electronic barostat (isobaric phasic distentions, 3 mmHg/1 min, interval 1 min) and a validated questionnaire. Personality features were evaluated by means of the Big Five Questionnaire for Children. Sleep, mood disturbance, anxiety and individual performance (missed school days, school results and social activities) were also evaluated. Children with irritable bowel syndrome showed significantly lower thresholds for discomfort (14.8 ± 3.5 vs 22.3 ± 6.9 mmHg, P = 0.010) and a higher cumulative perception score (28.2 ± 11.1 vs 12.3 ± 8.0, P = 0.005) compared with healthy controls. A higher emotional instability (57.8 ± 7.0 vs 48.7 ± 10.1, P = 0.047), sleep disturbance (7.2 ± 1.0 vs 9.3 ± 0.5, P = 0.004) and anxiety (6.3 ± 2.0 vs 2.3 ± 1.7, P = 0.009) were observed in irritable bowel syndrome patients. Moreover, in a multivariate analysis, the cumulative perception score was significantly related to emotional instability (P = 0.042). In conclusion children with irritable bowel syndrome exhibit visceral hypersensitivity and psychosocial impairment. Emotional instability, as a personality feature in these children, seems to modulate the perception response to visceral stimulations.
Effects of temperature, ultraviolet radiation and pectin methyl esterase on aerobic methane release from plant material
Authors: Bruhn D. , Mikkelsen T. N. , Øbro J. , Willats W. G. T. , Ambus P.
Published: March 2009

This study examines the effects of different irradiance types on aerobic methane (CH4) efflux rates from terrestrial plant material. Furthermore, the role of the enzyme pectin methyl esterase (PME) on CH4 efflux potential was also examined. Different types of plant tissue and purified pectin were incubated in glass vials with different combinations of irradiation and/or temperature. Purified dry pectin was incubated in solution, and with or without PME. Before and after incubation, the concentration of CH4 was measured with a gas chromatograph. Rates of CH4 emission were found to depend exponentially on temperature and linearly on UV‐B irradiance. UV‐B had a greater stimulating effect than UV‐A, while visible light had no effect on emission rates. PME was found to substantially reduce the potential for aerobic CH4 emissions upon demethylation of pectin.
Review article: Drug‐induced anti‐neutrophil cytoplasmic antibody‐associated vasculitis
Authors: GAO YING , ZHAO MING‐HUI
Published: March 2009

A recent development in the field of vasculitis is the increasing recognition that certain medications such as propylthiouracil can induce anti‐neutrophil cytoplasmic antibodies (ANCA)‐associated vasculitis (AAV). This review focuses on the data on causal drugs, possible pathogenesis, clinical description, diagnosis, treatment and prognosis of patients with drug‐induced AAV. The pathogenesis of drug‐induced AAV might be multifactorial. The clinical manifestations are similar to those of primary AAV, but ANCA with multi‐antigenicity may help to differentiate it from primary AAV. The diagnosis of drug‐induced AAV is based on the temporal relationship between clinically evident vasculitis and administration of the offending drugs, and excluding medical conditions that mimic vasculitis and other definable types of vasculitis. After the diagnosis of drug‐induced AAV was made, the offending drugs should be withdrawn immediately, and appropriate immunosuppressive therapy should be administered only for patients with vital organ involvement. The duration of immunosuppressive therapy should be much shorter than that in primary AAV and long‐term maintenance therapy might not be necessary. The prognosis of patients with drug‐induced AAV is good as long as the offending drug is discontinued in time.
Quantitative detection of HCMV‐DNA in saliva from infants and breast milk on real‐time polymerase chain reaction
Authors: Murata Hiroaki , Nii Ritsue , Ito Masahiro , Ihara Toshiaki , Komada Yoshihiro
Published: March 2009

Background:  The role of breast milk in viral transmission has not been fully studied. To determine the effect of breast milk on the establishment of primary human cytomegalovirus (HCMV) infection in term infants, HCMV‐DNA was measured in breast milk and infant saliva.

Methods:  The study population consisted of 48 healthy term infants and their mothers. The copy number of HCMV‐DNA in the infants' saliva and mothers' milk was measured on quantitative real‐time polymerase chain reaction (PCR).

Results:  HCMV‐DNA was detected in both saliva and breast milk from 21 infant–mother pairs, in milk only from four pairs, in saliva only from 12 pairs, and in neither from 11 pairs. HCMV‐DNA was first detected in the saliva of 10 infants at age 4 months, seven infants at 7 months, 13 infants at 10 months, and three infants at 12 months. The viral loads peaked 4–10 months after birth, and thereafter decreased or became negative. The peak copy number and rate of HCMV‐DNA detection in saliva were significantly related to peak copy number and rate of detection in the corresponding breast milk.

Conclusion:  Thus, HCMV passed through breast milk 1–7 months after delivery affects the persistence and level of HCMV‐DNA in infant saliva and is the most important route of primary infection.
Cardiac troponin T is not increased in patients with hypothyroidism
Authors: Ness‐Abramof R. , Nabriski D. A. , Shapiro M. S. , Tripto‐Shkolnik L. , Katz B. , Weiss E. , Shenkman L.
Published: March 2009

Patients with hypothyroidism often have increased creatine kinase (CK) levels. It is possible that there is increased production of CK, but other mechanisms, such as an increased cell membrane permeability or decreased enzyme clearance were also proposed. Recently, troponins T and I have been extensively studied because of their cardiac specificity. Cardiac troponins are sensitive and specific markers of cardiac injury. The objective of the study was to measure cardiac troponin T (cTnT) levels in patients with hypothyroidism. Twenty‐five patients with primary hypothyroidism were evaluated (thyroid‐stimulating hormone (TSH) >30 mU/L and low FT4). In all patients thyrotropin (TSH), free thyroxine (FT4), CK, CK‐MB and cTnT were measured.There were 3 men and 22 women with a mean age of 47.5 ± 12.4 years. TSH levels ranged from 31 to 75 mIU/L and mean FT4 levels were 4.5 ± 1.9 pmol/L. CK was normal in 11 patients and increased in 14. CK levels ranged between 86 and 1221 U/L (normal levels <170 in women, <195 in men) with a mean of 322 U/L ± 279. CK‐MB was increased in 4 patients (16%) and normal in 21. All 25 patients had normal cTnT levels, < 0.01 ng/mL (normal levels 0–0.1 μg/L). Increase in CK and its MB fraction are common in patients with hypothyroidism but cTnT levels are not, even in patients with increased CK‐MB. Therefore, cTnT is a reliable marker of cardiac injury even in the hypothyroid patient.
Urinary nerve growth factor level is correlated with the severity of neurological impairment in patients with cerebrovascular accident
Authors: Liu Hsin‐Tzu , Liu An‐Bang , Chancellor Michael B. , Kuo Hann‐Chorng
Published: March 2009

OBJECTIVE

To measure urinary nerve growth factor (uNGF, essential in nerve growth and regeneration) levels in patients with a cerebrovascular accident (CVA), to determine whether uNGF could be a biomarker for predicting the neurological deficits in CVA, as the level of uNGF increases in patients with idiopathic detrusor overactivity (DO) and incontinence.

PATIENTS, SUBJECTS AND METHODS

uNGF levels were measured using an enzyme‐linked immunosorbent assay in normal subjects and patients with CVA and different severities of neurological impairment. Total uNGF levels were normalized to the concentration of urinary creatinine (uNGF/Cr).

RESULTS

The median (interquartile range) uNGF/Cr levels were significantly higher in patients, at 0.13 (0–1.04), than in normal subjects (undetectable). The uNGF/Cr levels correlated well with the severity of neurological impairment. Patients with none/minimal neurological impairment had no detectable uNGF/Cr level, like the controls. Patients with mild/moderate impairment had levels of 0.27 (0.09–0.8) and with severe impairment level of 1.53 (0.5–3.0) (both P < 0.001), significantly greater than that of none/minimal impairment or controls. However, uNGF/Cr levels were not correlated with age, location of CVA, multiplicity of CVA, duration of CVA, urodynamic findings or the presence of urge urinary incontinence.

CONCLUSIONS

The uNGF level is correlated with the severity of neurological impairment in patients with CVA but not with urge symptoms or urodynamic findings, suggesting elevated uNGF might be a result of the neurological lesion rather than lower urinary tract dysfunction in CVA.
The usability of a Norwegian adaptation of the Children's Communication Checklist Second Edition (CCC‐2) in differentiating between language impaired and non‐language impaired 6‐ to 12‐year‐olds
Authors: HELLAND WENCHE ANDERSEN , BIRINGER EVA , HELLAND TURID , HEIMANN MIKAEL
Published: March 2009

The aim of the present study was to evaluate if the Norwegian adaptation of the Children's Communication Checklist‐2 (CCC‐2) differentiates between a language impaired and a non‐language impaired population and to make a first evaluation of the psychometric qualities of the questionnaire on a Norwegian sample. A total of 153 children aged 6–12 years participated in the study (45 language impaired and 108 non‐language impaired). The Norwegian adaptation of the CCC‐2 distinguished language impaired from non‐language impaired children and thus seems to provide a useful screening tool for communication impairments in Norwegian children. The reliability of the CCC‐2 appeared to be reasonable with internal consistency values ranging from 0.73 to 0.89.
Ring 14 chromosome presenting as early‐onset isolated partial epilepsy
Authors: VILLE DOROTHÉE , DE BELLESCIZE JULITTA , NGUYEN MARIE ANGE , TESTARD HERVÉ , GAUTIER AGNÈS , PERRIER JULIE , TILL MARIANNE , DES PORTES VINCENT
Published: March 2009

We report four infants (two males, two females) with ring 14 chromosome presenting with early‐onset partial epilepsy. The first seizure occurred between 3 and 6 months (3, 3, 4, and 6mo respectively). In all four cases, diagnosis was based on early focal seizures, rather than on psychomotor retardation or morphological features, which were not prominent at seizure onset. Moreover, despite the young age of the patients and the high frequency of seizures, neither epileptic spasms nor progression to ‘epileptic encephalopathy’, such as hypsarrhythmia, were observed. Epilepsy remained partial in these patients. At the most recent follow‐up, all four children had slight or mild psychomotor delay, and two of them had moderate non‐specific dysmorphic traits. Data from the literature about epilepsy in ring 14 chromosome syndrome were also reviewed. Ring 14 chromosome syndrome may be revealed by isolated, early‐onset focal epilepsy suggestive of focal lesions with only mild mental retardation and morphological features at the time of diagnosis. The characteristics of these observations differ from classic ring 14 syndrome, and may enlarge this clinical spectrum. Many unanswered questions remain concerning phenotype–genotype correlation and identification of the potential genes and molecular mechanisms responsible for epilepsy in patients with ring 14 syndrome.
Neuropsychological profile of children with subcortical band heterotopia
Authors: SPENCER‐SMITH MEGAN , LEVENTER RICHARD , JACOBS RANI , LUCA CINZIA DE , ANDERSON VICKI
Published: March 2009

Aim  Subcortical band heterotopia (SBH) or ‘double cortex’ is a malformation of cortical development resulting from impaired neuronal migration. So far, research has focused on the neurological, neuroimaging, and genetic correlates of SBH. More recently, clinical reports and small sample studies have documented neuropsychological dysfunction in patients with this malformation. This study aimed to characterize further the phenotype of patients with SBH by describing the neuropsychological profiles of children.

Method  Seven children (six females) aged 4 to 15 years were assessed for cognitive functioning (intellectual ability, processing speed, attention, working memory) and academic achievement (reading, spelling, arithmetic). Parents completed questionnaires examining their child’s social skills and problem behaviours. Magnetic resonance images (MRI) conducted for routine clinical follow‐up were coded by a paediatric neurologist. Genetic and seizure history were obtained from medical records.

Results  There was variation in the neurological, neuroimaging, and genetic presentation of children in the sample. Impairments were observed in all areas of neuropsychological functioning examined. Intellectual ability was generally within the ‘extremely low’ range (full‐scale IQ 44–74; performance IQ 45–72; verbal IQ 57–80). Generalized impairments in cognitive skills were typical, with severe impairments (scores greater than 2SD below the test mean) reported in processing speed, working memory, and arithmetic. Impairments in academic, social, and behavioural functioning were less generalized. No clear relationship between neuroimaging and neuropsychological impairments was found.

Interpretation  Children with SBH demonstrate cognitive, academic, social, and behavioural problems, with the greatest difficulties in processing speed and complex cognitive skills.
Reorienting consumer education using social learning theory: sustainable development via authentic consumer pedagogy
Authors: McGregor Sue L.T.
Published: March 2009

The paper illustrates the growing interest in understanding consumer behaviour through a social learning theory (SLT) lens, and explains the recently launched United Nations Decade for Education for Sustainable Development (ESD). Then, the discussion turns to an overview of a recently developed ESD/SLT integrated theoretical framework, which is then applied to consumer education via an authentic pedagogy. The paper highlights the rich potential of authentic intellectual work in the form of observational learning by augmenting ESD within authentic consumer education curricula.
Imaging vulnerability: the iconography of climate change
Authors: Manzo Kate
Published: March 2009

This paper explores the iconography of climate change in contemporary climate action campaigns in the UK. I aim to show how sample images are simultaneously scientific denotations of global warming and cultural connotations of danger and vulnerability. I further demonstrate that while similar images are associated with different agendas and geographical visions, they attach to a shared discourse of vulnerability that has Western (colonial) roots. The paper concludes with an overview of possible ways for climate action campaigns to effectively convey their political messages without recycling colonial visions of the world.
To please or to neglect your partner? Attachment avoidance and relationship‐driven self‐improvement
Authors: MING HUI CHIN , HARRIS BOND MICHAEL
Published: March 2009

Self‐improvement is a potential resource in sustaining relationships. A series of 2 studies with Hong Kong Chinese college samples sought to examine whether attribute‐specific, reflected regard from the partner determines self‐improvement efforts on those attributes and whether attachment avoidance moderates the association. These studies measured self‐improvement effort by retrospective self‐report (Study 1) and evaluation of objects pertinent to attribute‐specific self‐improvement goals (i.e., related self‐help books; Study 2). In general, the results showed that individuals improved their personal qualities when they perceived these qualities as relatively less favorably regarded by their partner. Moreover, attachment avoidance weakened such an association. The role of attachment avoidance in relationship‐driven self‐improvement seems to reflect strategic preference rather than a downplaying of relationship importance.
Age‐ and gender‐specific distributions of hepatitis B virus (HBV) genotypes in Japanese HBV‐positive blood donors
Authors: Yoshikawa Akira , Gotanda Yuko , Suzuki Yoshiharu , Tanaka Masako , Matsukura Harumichi , Shiraishi Toshio , Matsubayashi Keiji , Kon Emi , Suzuki Ko , Yugi Hisao ,   the Japanese Red Cross HBV Genotype Research Group
Published: March 2009

BACKGROUND: There are an increasing number of reports on the hepatitis B virus (HBV) genotype distribution in acute or chronic HBV‐infected patients in Japan; however, reports on the HBV genotype of blood donors are few. To compare the HBV genotypes of hepatitis B surface antigen (HBsAg)‐positive blood donors with infected patients, all the HBsAg‐positive donors' genotypes were determined.

STUDY DESIGN AND METHODS: Data on Japanese blood donors from October 2006 to September 2007 were obtained from the Japanese Red Cross database. The number of available samples was 1979, and the HBV genotypes were determined in 1887 samples. The six major genotypes of HBV (A‐F) were determined by enzyme‐linked immunosorbent assay. The presence of the immunoglobulin M (IgM) antibody against the HBV core antigen was determined by enzyme immunoassay among all HBsAg‐positive donors.

RESULTS: A significant difference in the HBV genotype distribution between donors and patients was in the C/B genotype ratio. The ratios were low in blood donors (2.0‐3.9) and high in patients (5.3‐18.2). The genotype B ratio increases from 13.8% in teenage donors to 42.4% in those in their 50s; however; the genotype C ratio decreases from 83.1% in teenage donors to 55.1% in those in their 50s. In both IgM antibody against hepatitis B core antigen and nucleic acid test–positive donors, genotypes A and B were restricted to male donors.

CONCLUSIONS: The age‐specific distribution of HBV genotypes in Japanese blood donors was observed in the B/C genotype ratio. The gender‐specific distribution of HBV genotype A, which originated from the US or Western countries, was observed in male Japanese donors.
Ionic Conductivity Enhancement of La2Mo2−xWxO9 Nanocrystalline Films Deposited on Alumina Substrates by the Sol–Gel Method
Authors: Zhuang Zhong , Wang Xian Ping , Li Dan , Zhang Tao , Fang Qian Feng
Published: March 2009

Dense, crack‐free, and uniform La2Mo2−xWxO9 (x=0, 0.1, and 0.2) nanocrystalline films were successfully synthesized on poly‐alumina substrates via a modified sol–gel method, with inorganic salt of La(NO3)3·6H2O, (NH4)6Mo7O24·4H2O, and (NH4)6H2W12O24 as precursors. Pure La2Mo2O9 phase was confirmed by X‐ray diffractometer when the annealing temperature was >500°C. The average grain size of the La2Mo2−xWxO9 films is in the range of 90–400 nm, depending upon the conditions of thermal treatment, and the thickness of films can reach 1 μm by repetitive spin‐coating. The electrical conductivity increases with decreasing grain size and reaches 0.074 S/cm at 600°C in the film with a grain size of 90 nm, which is one order of magnitude higher than that in the corresponding bulk materials. W‐doping can suppress the phase transition that occurs at 580°C in pure La2Mo2O9 and enhance the low‐temperature ionic conductivity. Furthermore, the activation energy of conductivity in the nanocrystalline La2Mo2O9 films decreases to about 0.6 eV in comparison with 1.0 eV in the bulk ones, which implies that the grain resistance prevails in the total resistance, when grain size reduces to nanometer domain.
The Preparation of Barium Hexaferrite Coatings Using HVOF
Authors: Lisjak Darja , Makovec Darko , Gyrgyek Sašo , Hujanen Arto , Lintunen Pertti , Varis Tommi , Bolelli Giovanni , Lusvarghi Luca , Drofenik Miha
Published: March 2009

Thick coatings of barium hexaferrite with the compositions BaFe12O19 and BaCoTiFe10O19 were prepared using high‐velocity oxygen‐fuel (HVOF) spraying technology. Nanocrystalline precursors embedded in an amorphous matrix were obtained on both Fe and glass–ceramic substrates. To promote the crystallization of the hexaferrites, the coatings were annealed at 800°–1000°C, and single‐phase coatings were obtained at 1000°C. The crystallization process was studied with X‐ray powder diffraction and with electron microscopy. The magnetic measurements of the coatings were carried out in a static field and at high frequencies. The magnetization of the coatings increased with the annealing temperature to above 50 emu/g for both compositions. The coercivity of BaFe12O19 increased with the annealing temperature to above 2400 Oe, whereas the coercivity of BaCoTiFe10O19 decreased from over 800 Oe, for the as‐deposited sample, to 400 Oe for the sample annealed at 1000°C. A minimum 90% absorption was calculated for the BaFe12O19 coatings with thicknesses of 0.15–0.25 mm at around 47 GHz and for the 1–4‐mm‐thick coatings of BaCoTiFe10O19 at 3–9 GHz.