bluuebunny/crossref_metadata_2025 huggingface dataset:
Volumetric Properties of Single Aqueous Electrolytes from Zero to Saturation Concentration at 298.15 °K Represented by Pitzer’s Ion-Interaction Equations
Authors: Krumgalz Boris S. , Pogorelsky Rita , Pitzer Kenneth S.
Published: June 2010

The ion interaction approach developed by Pitzer allows the prediction of various thermodynamic characteristics of multiple-solute electrolyte solutions, if the respective parameters for each type of single-solute electrolyte solution are known. The present paper discusses the Pitzer approach to the calculations of the volumetric properties of single-solute electrolyte solutions. The databases for the densities and the apparent molal volumes versus concentrations were created at 298.15 °K using essentially all published relevant data for each single-solute electrolyte solution. Poor experimental data were discarded by a statistical treatment applied to these databases. Proper treatment of all good quality density and apparent molal volume data, in a wide range of concentrations from infinite dilution through saturation, allowed us to evaluate the volumetric ion interaction parameters (V̄0MX, βMX(0)V, βMX(1)V, βMX(2)V, and CMXV) at 298.15 °K for 102 electrolytes. Strong linear relationships between the βMX(1)V, βMX(2)V, or CMXV, and βMX(0)V volumetric ion interaction parameters were observed for all analyzed solutes with slopes depending on the solute valency types.
NIST-JANAF Thermochemical Tables for Oxygen Fluorides
Authors: Chase M. W.
Published: June 2010

The thermodynamic and spectroscopic properties of the oxygen fluoride species have been reviewed. Recommended thermochemical tables are given for five gaseous oxygen fluorides: OF, OFO, FOO, FOF, and O2F2. Sufficient information is not available to generate thermochemical tables for any condensed phase species. Annotated bibliographies (over 600 references) are provided for all neutral oxygen fluorides which have been reported in the literature. There are needs for additional experimental and theoretical data to reduce the uncertainties in the recommended values for these five species. Of all the species mentioned in the literature, many have not been isolated and characterized. In fact, some do not exist. Throughout this paper, uncertainties attached to recommended values correspond to the uncertainty interval, equal to twice the standard deviation of the mean.
Electron Interactions with CCl2F2
Authors: Christophorou L. G. , Olthoff J. K. , Wang Yicheng
Published: June 2010

In this article, available information on the cross sections and rate coefficients for collisional interactions of dichlorodifluoromethane (CCl2F2) with electrons is critically evaluated and synthesized. This gas has many industrial uses and is of atmospheric and environmental interest. The CCl2F2 molecule fragments rather extensively under electron impact, principally via dissociative ionization and dissociative attachment; the latter process is temperature dependent. Information is presented and discussed on: (1) electron scattering processes [cross sections for total electron scattering, momentum transfer, differential elastic electron scattering, integral elastic electron scattering, and inelastic electron scattering for rotational and vibrational (direct and indirect) excitation]; (2) electron impact ionization (cross sections for total, partial, and double ionization and coefficients for electron impact ionization); (3) electron attachment (electron attachment cross sections and rate constants and their energy and temperature dependencies, electron attachment coefficients, dissociative attachment fragment anions, and negative ion states); (4) optical emission under electron impact, and (5) electron transport coefficients (electron drift velocity and ratio of transverse electron diffusion coefficient to electron mobility). Based upon the assessment of published experimental data, recommended values of various cross sections and rate coefficients are generated in graphical and tabular form. Areas where additional data are needed are identified, such as the measurement of the cross sections for momentum transfer and electron impact dissociation of CCl2F2 into neutral species.
Interpolation Correlations for Fluid Properties of Humid Air in the Temperature Range 100 °C to 200 °C
Authors: Melling Adrian , Noppenberger Stefan , Still Martin , Venzke Holger
Published: June 2010

This paper provides simple analytical correlations for selected thermodynamic and fluid transport properties for the mixture dry air and water vapor. These correlations are derived from theory as well as from numerical fitting procedures and give expressions for density ϱ, viscosity μ, thermal conductivity k, specific heat cp, and Prandtl number Pr at a working pressure of p=1 bar and for a temperature range from 100 °C to 200 °C. The main purpose is to present a comparatively simple set of equations, as the correlations do not reflect in every case the underlying physical background. Since experimental data are scarce for the properties under investigation, it was in some cases necessary to extrapolate the available correlations to temperatures or water vapor contents where no experimental data could be found. The derived equations are compared with the pure component values for dry air and water vapor and, as far as possible, also for air-water vapor mixtures.
A Compilation of Energy Levels and Wavelengths for the Spectrum of Neutral Beryllium (Be I)
Authors: Kramida A. , Martin W. C.
Published: June 2010

In this compilation we have used data from some 20 references, only two of which were available to C. E. Moore for her 1949 Atomic Energy Levels tables. The new compilation thus includes significant revisions, extensions, and improvements of the earlier data for configurations of the types 1s22snl and 1s22pnl and also extends the energy range to higher configurations, including those involving 1s electron excitation. The observed wavelengths for some 200 lines are given with their energy-level classifications. The wavelength measurements, which extend from 89 to 31 780 Å, were obtained from emission spectra of hollow-cathode and arc discharges, beam-foil spectra, and far-ultraviolet photoabsorption spectra. In addition to the energy levels derived from these spectra, we include levels obtained from multiphoton resonance-ionization mass spectrometry and projectile-Auger spectroscopy. We have evaluated a number of levels by using series formulas and/or theoretical results; these levels are more accurate than values derived from available wavelength measurements. Wavelengths calculated from energy-level differences are given for all lines; these “Ritz” wavelengths are more accurate than the observed values wherever the differences are significant.
Material Properties of a Sintered α-SiC
Authors: Munro R. G.
Published: June 2010

A self-consistent, single-valued representation of the major physical, mechanical, and thermal properties of a sintered α-SiC is presented. This comprehensive set of properties is achieved by focusing on a narrowly defined material specification in which boron and carbon are used as sintering aids to produce a dense ceramic (⩾98% of the theoretical maximum density) with a grain size of (6±2) μm. Such a representation is highly desirable in applications of concurrent engineering practices and for the increasing use of electronic processing of product specifications.
Atomic Weights of the Elements 1995
Authors: Coplen T. B.
Published: June 2010

The biennial review of atomic weight, Ar(E), determinations and other cognate data has resulted in changes for the standard atomic weight of 21 elements. The five most significant changes are: boron from 10.811±0.005 to 10.811±0.007; carbon from 12.011±0.001 to 12.0107±0.0008; arsenic from 74.92159±0.00002 to 74.92160±0.00002; cerium from 140.115±0.004 to 140.116±0.001; and platinum 195.08±0.03 to 195.078±0.002. An annotation for potassium has been changed in the Table of Standard Atomic Weights. To eliminate possible confusion in the reporting of relative lithium isotope-ratio data, the Commission recommends that such data be expressed using Li/7Li6 ratios and that reporting using Li/6Li7 ratios be discontinued. Because relative isotope-ratio data for sulfur are commonly being expressed on noncorresponding scales, the Commission recommends that such isotopic data be expressed relative to VCDT (Vienna Cañon Diablo Troilite) on a scale such that S/34S32 of IAEA-S-1 silver sulfide is 0.9997 times that of VCDT. Many elements have a different isotopic composition in some nonterrestrial materials. Some recent data on oxygen are included in this article for the information of the interested scientific community.
The Vapor Pressure of Environmentally Significant Organic Chemicals: A Review of Methods and Data at Ambient Temperature
Authors: Delle Site Alessandro
Published: June 2010

The experimental techniques and the prediction procedures for the determination or evaluation of the vapor pressure of environmentally relevant organic compounds are described; with 259 references examined. For each of them the characteristics of precision and accuracy are given, when available from the literature. The experimental methods are classified as “direct” and “indirect.” The first class includes all those which can measure directly the vapor pressure, while the second concerns those which need “known” vapor pressures of reference compounds for the calibration. Prediction methods are based on the application of the Clapeyron–Clausius equation or on the quantitative structure-property relationships. Also correlation methods require a suitable calibration. The vapor pressures at ambient temperature for several polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and furans, selected pesticides, and some reference compounds are tabulated together with the vapor pressure equations and the enthalpy values in the temperature range of measurement. A critical comparison, based on a statistical analysis of the data obtained with different methods and derived from 152 references, is also carried out.
Homologous Series of Liquid Crystalline Steroidal Lipids
Authors: Thiemann Thies , Vill Volkmar
Published: June 2010

Steroids are an important source of chiral mesophases. The melting behavior and mesomorphic properties of homologous series of steroidal derivatives have been extracted from the literature, tabulated, and discussed. The tables provide the reader with an evaluated compilation of the type of mesophases found for the individual compounds, including their transition temperatures. Where the literature gives more than one set of data for a specific substance, one has been chosen as the main reference, but all alternatives are listed in the footnotes. The data can be used for statistical analysis to show the specific role of substructures within the steroidal framework.
Gas-Phase Tropospheric Chemistry of Volatile Organic Compounds: 1. Alkanes and Alkenes
Authors: Atkinson R.
Published: June 2010

Literature data (through mid-1996) concerning the gas-phase reactions of alkanes and alkenes (including isoprene and monoterpenes) leading to their first generation products are reviewed and evaluated for tropospheric conditions. The recommendations of the most recent IUPAC evaluation [J. Phys. Chem. Ref. Data, 26, No. 3 (1997)] are used for the ⩽C3 organic compounds, unless more recent data necessitates reevaluation. The most recent review and evaluation of Atkinson [J. Phys. Chem. Ref. Data, Monograph 2, 1 (1994)] concerning the kinetics of the reactions of OH radicals, NO3 radicals, and O3 is also updated for these two classes of volatile organic compounds.
A Helmholtz Free Energy Formulation of the Thermodynamic Properties of the Mixture {Water + Ammonia}
Authors: Tillner-Roth Reiner , Friend Daniel G.
Published: June 2010

A thermodynamic model incorporating a fundamental equation of state for the Helmholtz free energy of the mixture {water+ammonia} is presented which covers the thermodynamic space between the solid–liquid–vapor boundary and the critical locus. It is also valid in the vapor and liquid phases for pressures up to 40 MPa. It represents vapor–liquid equilibrium properties with an uncertainty of ±0.01 in liquid and vapor mole fractions. Typical uncertainties in the single-phase regions are ±0.3% for the density and ±200 J mol−1 for enthalpies. Details of the data selection and the optimization process are given. The behavior of the fundamental equation of state is discussed in all parts of the thermodynamic space.
Vibrational and Electronic Energy Levels of Polyatomic Transient Molecules. Supplement A
Authors: Jacox Marilyn E.
Published: June 2010

A summary is presented of recently published, critically evaluated experimental vibrational and electronic energy level data for neutral and ionic transient molecules and high temperature species possessing from three to sixteen atoms. Although the emphasis is on species with lifetimes too short for study using conventional sampling techniques, there has been selective extension of the compilation to include data for isolated molecules of inorganic species such as the heavy-metal oxides, which are important in a wide variety of industrial chemical systems. Radiative lifetimes and the principal rotational constants are included. Observations in the gas phase, in molecular beams, and in rare-gas and diatomic molecule matrices are evaluated. The types of measurement surveyed include conventional and laser-based absorption and emission techniques, laser absorption with mass analysis, and photoelectron spectroscopy. Not counting isotopic species, 904 molecules are surveyed, and 2696 distinct references are given.
Data on Internal Rarefied Gas Flows
Authors: Sharipov Felix , Seleznev Vladimir
Published: June 2010

The present review, containing 178 references, is dedicated to one of the largest and most important branches of the rarefied gas dynamics, namely internal flows. A critical analysis of the corresponding numerical data and analytical results available in the literature was made. The most reliable data were selected and tabulated. The review will be useful as a reference for mathematicians, physicists and aerodynamicists interested in rarefied gas flows. In this paper the complete ranges of the main parameters, determining rarefied gas flows through a capillary, are covered. The capillary length varies from zero, when the capillary degenerates into a thin orifice, to infinity when the end effects can be neglected. The Knudsen number, characterizing the gas rarefaction, varies from zero when the gas is considered as a continuous medium to infinity when the intermolecular collisions can be discounted. The pressure and temperature drops on the capillary ends vary from the small values when the linear theory is valid to the large values when the nonlinear equations must be applied. The influence of the gas–surface interaction is considered.
Energetics of the O–H Bond in Phenol and Substituted Phenols: A Critical Evaluation of Literature Data
Authors: Borges dos Santos Rui M. , Martinho Simões José A.
Published: June 2010

This review presents a critical assessment of the available experimental information (contained in ∼90 literature references) on the thermochemistry of the O–H bond in phenol and substituted phenols. The analysis led to a set of recommended values for the O–H bond dissociation enthalpies, which in turn allowed us to discuss several empirical and theoretical methodologies used to estimate these data.
Thermochemistry of the Boranes
Authors: Yu C.-L. , Bauer S. H.
Published: June 2010

A compilation is presented of published experimental and computational reports (191 references) on the structures, vibrational frequencies, molar enthalpies of formation and standard entropies for 26 gas phase boranes for the temperature range from 0 to 1500 K. The thermochemical properties have been collated via standard programs and are listed in a convenient tabular format. Levels of uncertainties in the thermodynamic functions have not been assessed, because of the limited experimental and computational data. The tabulated values were fitted to standard seven-parameter (NASA) polynomials to facilitate the computation of enthalpies of formation, entropies, and heat capacities for modeling purposes. Within the context of intrinsic uncertainties, the equilibrium compositions of the gas phase were calculated, constrained to constant temperature and volume, for several boron–hydrogen (B/H) ratios, at various temperatures and pressures. The (unexpected) results indicate that in none of the reported gas-phase kinetics studies was thermodynamic equilibrium attained, even though the measured concentration profiles appear to extrapolate to steady state product distributions.
Simultaneous Assessment of the YBa2Cu3O6+z Thermodynamics Under the Linear Error Model
Authors: Rudnyi E. B. , Kuzmenko V. V. , Voronin G. F.
Published: June 2010

About 3000 experimental points obtained in 220 miscellaneous experiments published in 57 papers have been processed simultaneously in order to obtain the most reliable Gibbs energy of the YBa2Cu3O6+z solid solution in the temperature range from 250 to 1300 K. A part of this solution is well-known as the “Hi-Tc Y123” phase. All other thermodynamic properties of the solution including the conditions for the tetragonal-orthorhombic phase transition and the miscibility gap at lower temperatures, are derived from the assessed Gibbs energy. The linear error model introduced recently by one of the authors has been employed for the simultaneous assessment. The results obtained are compared with those of the conventional weighted least squares method and the benefit of the new approach is discussed. Another problem in simultaneous assessment that is also considered is visualizing the quality of the fit. New types of graphs (partly based on the linear error model) that facilitate visualizing the quality of the fit are presented. (A critical review with 72 references.)
Revised Formulation for the Refractive Index of Water and Steam as a Function of Wavelength, Temperature and Density
Authors: Harvey Allan H. , Gallagher J. S. , Sengers J. M. H. Levelt
Published: June 2010

Schiebener et al. published a formulation for the refractive index of water and steam in 1990 [J. Phys. Chem. Ref. Data 19, 677 (1990)]. It covered the ranges 0.2 to 2.5 μm in wavelength, −12 to 500 °C in temperature, and 0 to 1045 kg m−3 in density. The formulation was adopted by the International Association for the Properties of Water and Steam (IAPWS) in 1991. In the present article, the data, after conversion to ITS-90, have been refitted to the same functional form, but based on an improved equation of state for water adopted by IAPWS in 1995. The revised coefficients are reported, and some tabular material is provided. The revised refractive-index formulation was adopted by IAPWS in 1997 and is available as part of a National Institute of Standards and Technology Standard Reference Database. For most conditions, the revised formulation does not differ significantly from the previous one. A substantial improvement has been obtained in supercooled water at ambient pressure, where the previous formulation was defective. Special attention has been paid to the behavior of the refractive index in the near infrared, where strongly oscillating data were reported after the correlation of Schiebener et al. had appeared, leading to subsequent curtailing of the range of validity of the formulation. Newer results do not show these oscillations. They are compared with the revised formulation.
Global patterns of 16S rRNA diversity at a depth of millions of sequences per sample
Authors: Caporaso J. Gregory , Lauber Christian L. , Walters William A. , Berg-Lyons Donna , Lozupone Catherine A. , Turnbaugh Peter J. , Fierer Noah , Knight Rob
Published: June 2010

The ongoing revolution in high-throughput sequencing continues to democratize the ability of small groups of investigators to map the microbial component of the biosphere. In particular, the coevolution of new sequencing platforms and new software tools allows data acquisition and analysis on an unprecedented scale. Here we report the next stage in this coevolutionary arms race, using the Illumina GAIIx platform to sequence a diverse array of 25 environmental samples and three known “mock communities” at a depth averaging 3.1 million reads per sample. We demonstrate excellent consistency in taxonomic recovery and recapture diversity patterns that were previously reported on the basis of metaanalysis of many studies from the literature (notably, the saline/nonsaline split in environmental samples and the split between host-associated and free-living communities). We also demonstrate that 2,000 Illumina single-end reads are sufficient to recapture the same relationships among samples that we observe with the full dataset. The results thus open up the possibility of conducting large-scale studies analyzing thousands of samples simultaneously to survey microbial communities at an unprecedented spatial and temporal resolution.
Synaptonemal complex formation and meiotic checkpoint signaling are linked to the lateral element protein Red1
Authors: Eichinger Christian S. , Jentsch Stefan
Published: June 2010

Meiosis generates four haploid daughters from a diploid parental cell. Central steps of meiosis are the pairing and recombination of homologous chromosomes followed by their segregation in two rounds of cell division. Meiotic recombination is monitored by a specialized DNA damage checkpoint pathway and is guided by a unique chromosomal structure called synaptonemal complex (SC), but how these events are coordinated is unclear. Here, we identify the SC protein Red1 as a crucial regulator of early meiosis. Red1 interacts with two subunits of the 9-1-1 checkpoint complex via two distinct 9-1-1 subunit-specific motifs. Association of 9-1-1 with Red1 is essential not only for meiotic checkpoint activation but for SC formation. Moreover, Red1 becomes SUMO-modified, which fosters interaction of Red1 with the central SC element Zip1, thereby securing timely SC formation. Thus, Red1, in addition to its structural role in the SC, is a crucial coordinator of meiosis by coupling checkpoint signaling to SC formation.
Hyaluronan blocks oligodendrocyte progenitor maturation and remyelination through TLR2
Authors: Sloane J. A. , Batt C. , Ma Y. , Harris Z. M. , Trapp B. , Vartanian T.
Published: June 2010

Failure of remyelination is largely responsible for sustained neurologic symptoms in multiple sclerosis (MS). MS lesions contain hyaluronan deposits that inhibit oligodendrocyte precursor cell (OPC) maturation. However, the mechanism behind this inhibition is unclear. We report here that Toll-like receptor 2 (TLR2) is expressed by oligodendrocytes and is up-regulated in MS lesions. Pathogen-derived TLR2 agonists, but not agonists for other TLRs, inhibit OPC maturation in vitro. Hyaluronan-mediated inhibition of OPC maturation requires TLR2 and MyD88, a TLR2 adaptor molecule. Ablated expression of TLR2 also enhances remyelination in a lysolecithin animal model. Hyaluronidases expressed by OPCs degrade hyaluronan to hyaluronan oligomers, a requirement for hyaluronan/TLR2 signaling. MS lesions contain both TLR2
+
oligodendrocytes and low-molecular-weight hyaluronan, consistent with their importance to remyelination in MS. We thus have defined a mechanism controlling remyelination failure in MS where hyaluronan is degraded by hyaluronidases into hyaluronan oligomers that block OPC maturation and remyelination through TLR2-MyD88 signaling.
Marine (Aquaculture) Space Allocation: Assessing Transitional Challenges to Local Economies in New Zealand
Authors: Rennie Hamish G.
Published: June 2010

Local economies of marine areas are largely unexplored in mainline journals, perhaps because they have been considered marginal to the land, too underdeveloped, too specialised or of little importance in the local economy. The relatively recent emphasis on marine spatial planning and the development of offshore power generation has drawn attention to the importance of rights to marine areas. There exist natural tensions between activities that rely on the relatively permanent occupation of marine space (e.g. aquaculture) and those that require that same space for transitional periods of times, perhaps fleetingly, as space ‘to move through’ (e.g. fishing). Different methods of resolving these tensions can produce significant inequities, but less acknowledged is the potential for significant disruption of local economies caught in the contortions of transitions from one legislative regime to another. A recent aquaculture case in New Zealand serves as the basis for an analysis of issues of locality in decision-making when an existing rights holder seeks to renew those rights at a time of transition between one regime and another.
Slums of Hope: Land Tenure Reforms, Local Economic Development and Environmental Improvement in a Kenyan Shanty Town
Authors: Toomey Bernard
Published: June 2010

Kambi Moto is a village shack settlement in Nairobi's vast eastern peripheral slums. Kambi Moto differs from the slum around it, however, as it is in the middle of a community-led slum upgrading programme. This programme has instituted land tenure reform, house building, environmental improvements and has forced the local community to seek economic development. The environmental improvements include permanent, formal houses with electric, water and sanitation infrastructure provision. Roads were also built allowing better access to the community. Experts state that secure tenure leads to economic, health, education and other benefits (Durand-Lasserve & Selod, 2007). This ‘In Perspective’ case study will investigate the Kambi Moto experience to see if this holds true in practice.
The Effects of Taxation on Sustainable Development
Authors: Mcgill Greg
Published: June 2010

This paper is about the adverse effects the current system of taxation in the UK has on sustainable development. It reveals that by primarily focusing on two of the three factors of production, namely, labour and capital, these taxes encourage speculation in land and the withholding of land from productive use. This, in turn, discourages urban regeneration and encourages urban sprawl with further damaging consequences for housing, jobs, the economy and the environment. Overall, it leads to the inefficient, ineffective and inequitable use of land, which is unsustainable. In contrast, if taxation were shifted towards land instead of labour and capital, the effect would be to create more efficient, more effective and more equitable environments. Importantly, it would encourage sustainable development, the creation of more affordable housing and improve urban regeneration and local economies. It would also help rather than hinder the aims and objectives of town planning.
Motion Analysis of Thumb in Cellular Phone Use
Authors: Sakai Naotaka , Shimawaki Satoshi
Published: June 2010

The thumb motion of 10 normal subjects during cellular phone use was measured using a reflective marker detection system to compare the maximum, minimum and range of flexion angles of the interphalangeal (IP), metacarpophalangeal (MP) and carpometacarpal (CM) joints. Two micro‐reflective markers 3 mm in diameter were each placed on the dorsal surface of the distal phalanx, basal phalanx and metacarpal bone of the thumb. Three markers were placed on the dorsal hand in order to define the dorsal hand plane. Each subject pushed the 12 keys of a folding cellular phone with an 85‐mm‐long and 40‐mm‐wide keypad, sequentially from ‘1’ to ‘#’, and the pushing motion was recorded by six infrared video cameras for 12 seconds, using the VICON 612 system. The mean maximum flexion angle of the MP joint was significantly (p < .05) larger than the CM joint, and the mean minimum flexion angle of the CM joint was significantly (p < .01) smaller than the IP and MP joints. The mean range of motion of the IP joint was significantly (p < .05) larger than the MP and the CM joints. In a comparison of different key‐pushing motions, only the CM joint was significantly (p < .05) larger in its range of motion. In conclusion, thumb motion on pushing the keys of the cellular phone was produced mainly by the MP and the CM joints. In addition, the ability to reach keys in different areas of the cellular phone keypad is regulated by changing the flexion angle of the CM joint.
A Model of the Smooth Pursuit Eye Movement with Prediction and Learning
Authors: Zambrano Davide , Falotico Egidio , Manfredi Luigi , Laschi Cecilia
Published: June 2010

Smooth pursuit is one of the five main eye movements in humans, consisting of tracking a steadily moving visual target. Smooth pursuit is a good example of a sensory‐motor task that is deeply based on prediction: tracking a visual target is not possible by correcting the error between the eye and the target position or velocity with a feedback loop, but it is only possible by predicting the trajectory of the target. This paper presents a model of smooth pursuit based on prediction and learning. It starts from amodel of the neuro‐physiological system proposed by Shibata and Schaal (Shibata et al., Neural Networks, vol. 18, pp. 213‐224, 2005). The learning component added here decreases the prediction time in the case of target dynamics already experienced by the system. In the implementation described here, the convergence time is, after the learning phase, 0.8 s.
Exchange bias in LaFeO3 nanoparticles
Authors: Ahmadvand Hossein , Salamati Hadi , Kameli Parviz , Poddar Asok , Acet Mehmet , Zakeri Khalil
Published: June 2010

Nanoparticles of antiferromagnetic LaFeO3 were prepared by the sol–gel method. An exchange bias effect has been observed and is attributed to the exchange coupling between the ferromagnetic shell and antiferromagnetic core of the particles. The results provide clear evidence of the presence of spontaneous exchange bias in this system. After field cooling from room temperature, the exchange bias increases while the coercivity decreases with decreasing temperature. Taking into account the role of thermal activation, the temperature dependence of exchange bias and coercivity has been interpreted in terms of the spontaneous exchange bias mechanism proposed recently.
A general cloak to shift the scattering of different objects
Authors: Li Wei , Guan Jianguo , Wang Wei , Sun Zhigang , Fu Zhengyi
Published: June 2010

By introducing the concept of ‘minifying layer’, we propose a universal device to hide the position of an object by shifting its scattering without a scaling effect for distance, independent of the direction of incident wave and observation. Unlike the previously reported similar cloaks whose configurations are relevant to the objects to be cloaked, the design here is able to shift the scattering of various objects by one cloak. Moreover, by adjusting the parameter of the ‘minifying layer’, a tunable magnifying or even minifying effect on the shifted scattering can also be achieved. The performances of the devices are demonstrated by finite element simulations. This design provides a more flexible way to shift the scattering of an object, and thus can be expected to have wide applications.
Optical confinement using a doughnut waveguide
Authors: Tsai Ya-Lun , Hsu Kuei-Chu , Chen Chii-Chang , Chen Ching-Yi , Chang Jenq-Yang
Published: June 2010

This paper examines the photonic band gap of periodically arranged doughnuts (torus). Using the proposed structure as a hollow waveguide, it is possible to obtain the complete bandgap and optical confinement. The diameter of the outputted beam from the waveguide can be the same order of magnitude as the wavelength.
Current transfer in dc non-transferred arc plasma torches
Authors: Ghorui S , Sahasrabudhe S N , Das A K
Published: June 2010

Fundamentals of current transfer to the anodes in dc non-transferred arc plasma torches are investigated. Specially designed anodes made of three mutually isolated sections and external dc axial magnetic fields of various strengths are utilized to explore the conditions for different diffused and constricted attachments of the arc with the anode. A number of new facts are revealed in the exercise. Under constricted attachment, formation of arc root takes place. Spontaneous and magnetically induced movements of the arc root, their dependence on the arc current and the strength of the external magnetic field, most probable arc root velocity, variation of the root velocity with strength of the applied magnetic field, the effect of swirl on the rotational speed of the arc root are some of the important features investigated. Two new techniques are introduced: one for measurement of the arc root diameter and the other for determination of the negative electric field in the boundary layer over the anode. While the first one exploits the rigid column behaviour of the arcs, the second one utilizes the shooting back of the residual electrons over an arc spot. Sample calculations are provided.
A NiO/TiO2 junction electrode constructed using self-organized TiO2 nanotube arrays for highly efficient photoelectrocatalytic visible light activations
Authors: Guo Jin , Fu Wuyou , Yang Haibin , Yu Qingjiang , Zhao Wenyan , Zhou Xiaoming , Sui Yongming , Ding Juan , Li Yangen , Cheng Shuli , Li Minghui
Published: June 2010

One dimensional (1D), self-organized TiO2 nanotube arrays are known to have excellent charge transport properties and a NiO/TiO2 junction is efficient in separating electron–hole pairs. This paper describes the synthesis of a NiO/TiO2 junction electrode constructed using self-organized TiO2 nanotube arrays combining the above two properties. The self-organized TiO2 nanotube arrays used in this study were prepared by anodizing titanium films, which resulted in closely packed n-type TiO2 tubes with an inner pore diameter of 60–90 nm, a wall thickness of approximately 15 nm and a length of 600 nm. The NiO/TiO2 junction was synthesized by electroless plating and annealing which resulted in TiO2 nanotube arrays coated with a layer (about 200 nm in thickness) of NiO particles (20–40 nm). The resulting NiO/TiO2 junction electrode enabled us to obtain an enhanced photocurrent (3.05 mA cm−2) as compared with a TiO2 electrode based on TiO2 nanotube arrays (0.92 mA cm−2) under AM 1.5 G (100 mw cm−2) at a bias of 0.65 V.
Characterization of strain rate sensitivity and activation volume using the indentation relaxation test
Authors: Xu Baoxing , Yue Zhufeng , Chen Xi
Published: June 2010

We present the possibility of extracting the strain rate sensitivity, activation volume and Helmholtz free energy (for dislocation activation) using just one indentation stress relaxation test, and the approach is demonstrated with polycrystalline copper. The Helmholtz free energy measured from indentation relaxation agrees well with that from the conventional compression relaxation test, which validates the proposed approach. From the indentation relaxation test, the measured indentation strain rate sensitivity exponent is found to be slightly larger, and the indentation activation volume much smaller, than their counterparts from the compression test. The results indicate the involvement of multiple dislocation mechanisms in the indentation test.
A continuum model of piezoelectric potential generated in a bent ZnO nanorod
Authors: Shao Z Z , Wen L Y , Wu D M , Wang X F , Zhang X A , Chang S L
Published: June 2010

A continuum model of piezoelectric potential generated in a bent ZnO nanorod cantilever is presented by means of the first piezoelectric effect approximation. The analytical solution of the model shows that the piezoelectric potential in the nanorod is proportional to the lateral force but is independent along the longitudinal direction. The electric potential in the tensile area and that in the compressive area are antisymmetric in the cross section of the nanorod, which makes the nanorod a ‘parallel plate capacitor’ for piezoelectric nanodevices, such as a nanogenerator. The magnitude of piezoelectric potential for a ZnO nanorod of 50 nm diameter and 600 nm length bent by a 80 nN lateral force is about 0.27 V, which is in good agreement with the finite element method calculation.
From Farm Management to Agricultural and Applied Economics: The Expansion of a Professional Society as Seen Through a Census of its Dissertations From 1951 to 2005
Authors: Boland Michael A. , Crespi John M.
Published: June 2010

The authors provide a historical census of all 7,967 graduated doctoral students in agricultural economics from U.S. programs between 1951 and 2005. They provide the first comprehensive study of the history and current state of the highest degree of the agricultural economics profession, show how the degree and the journals in which dissertation research is published have changed over time, and discuss how the profession has evolved from farm economics to an agricultural and other applied economics fields.
Septic pneumonic tularaemia caused by Francisella tularensis subsp. holarctica biovar II
Authors: Fritzsch Joerg , Splettstoesser Wolf D.
Published: June 2010

This case of pneumonic tularaemia elucidates two aspects: it is believed to be the first documented case of bacteraemia caused by Francisella tularensis subsp. holarctica biovar II; furthermore, it illustrates the remission of septic pneumonic tularaemia without appropriate anti-infective therapy. A blood culture from a patient with community-acquired pneumonia was found to be positive for F. tularensis subsp. holarctica biovar II after 10 days of cultivation. Meanwhile, the patient had been treated with ceftriaxone, followed by sultamicillin and clindamycin. The patient continued suffering from fever of up to 40.7 °C and rising C-reactive protein (CRP) for 4 days before the fever and CRP declined. The isolated strain was later tested and found to be resistant to the antibiotics used. The present case underlines that F. tularensis subsp. holarctica infections may cause severe symptoms but mostly have a favourable outcome.
Molecular characterization of Mycobacterium intracellulare-related strains based on the sequence analysis of hsp65, internal transcribed spacer and 16S rRNA genes
Authors: Park Joo-Hee , Shim Tae-Sun , Lee Seung-Ae , Lee Hyungki , Lee In-Kyung , Kim Kijeong , Kook Yoon-Hoh , Kim Bum-Joon
Published: June 2010

We investigated the molecular epidemiological features of 94Mycobacterium intracellulare-related strains, isolated from Korean patients, using sequence analysis targeting 3 independent chronometer molecules,hsp65, the internal transcribed spacer 1 region and the 16S rRNA gene. By collective consideration of these three gene-based approaches, the 94 strains were divided into 5 groups (INT1, INT2, INT3, INT4 and INT5). The frequencies of genotype INT1, 2, 3, 4 and 5 in the 94 isolates were 57.4 % (54), 27.7 % (26), 6.4 % (6), 5.3 % (5) and 3.2 % (3), respectively. When correlations between genotypes and clinical parameters (age, sex, radiological type and the presence of a cavity) were analysed in 78 patients with non-tuberculous mycobacteria pulmonary diseases, no relationships were observed with respect to age, sex and radiological type, but genotype and the presence of a cavity tended to be related (P=0.051).
Mat fimbriae promote biofilm formation by meningitis-associated Escherichia coli
Authors: Lehti Timo A. , Bauchart Philippe , Heikkinen Johanna , Hacker Jörg , Korhonen Timo K. , Dobrindt Ulrich , Westerlund-Wikström Benita
Published: June 2010

The mat (or ecp) fimbrial operon is ubiquitous and conserved in Escherichia coli, but its functions remain poorly described. In routine growth media newborn meningitis isolates of E. coli express the meningitis-associated and temperature-regulated (Mat) fimbria, also termed E. coli common pilus (ECP), at 20 °C, and here we show that the six-gene (matABCDEF)-encoded Mat fimbria is needed for temperature-dependent biofilm formation on abiotic surfaces. The matBCDEF deletion mutant of meningitis E. coli IHE 3034 was defective in an early stage of biofilm development and consequently unable to establish a detectable biofilm, contrasting with IHE 3034 derivatives deleted for flagella, type 1 fimbriae or S-fimbriae, which retained the wild-type biofilm phenotype. Furthermore, induced production of Mat fimbriae from expression plasmids enabled biofilm-deficient E. coli K-12 cells to form biofilm at 20 °C. No biofilm was detected with IHE 3034 or MG1655 strains grown at 37 °C. The surface expression of Mat fimbriae and the frequency of Mat-positive cells in the IHE 3034 population from 20 °C were high and remained unaltered during the transition from planktonic to biofilm growth and within the matured biofilm community. Considering the prevalence of the highly conserved mat locus in E. coli genomes, we hypothesize that Mat fimbria-mediated biofilm formation is an ancestral characteristic of E. coli.
Mycobacterium tuberculosis protein kinase K confers survival advantage during early infection in mice and regulates growth in culture and during persistent infection: implications for immune modulation
Authors: Malhotra Vandana , Arteaga-Cortés Lourdes T. , Clay Gwendolyn , Clark-Curtiss Josephine E.
Published: June 2010

Mycobacterium tuberculosis serine/threonine protein kinases (STPKs) are key regulators of growth and metabolism; however, evidence for their roles in virulence is limited. In a preliminary screen based on comparative expression between strains H37Rv and H37Ra, six STPK genes, pknD, pknG, pknH, pknJ, pknK and pknL, showed higher expression in H37Rv. In the second screen, STPK expression was analysed in H37Rv-infected human macrophages. Interestingly, significant expression of pknK was detected only at 18 h post-infection, suggesting its involvement in early infection events. We have investigated the roles of PknK in vitro and in vivo. PknK levels were induced under stationary phase and deletion of pknK resulted in increased resistance of the mutant to acidic pH, hypoxia, oxidative and stationary-phase stresses in vitro. These results, together with the increased survival of the ΔpknK strain during persistent infection in mice, reveal a role for PknK in adaptive mechanisms that slow the growth of mycobacteria. A novel finding of this study was the inhibition of growth of ΔpknK strain during acute infection in mice that correlated with the significant upregulation of tumour necrosis factor as well as the simultaneous downregulation of interleukin-12p40, interferon-γ and induced nitric oxide synthase transcripts. Finally, we provide evidence for the localization of PknK during infection and discuss its implications in pathogenesis.
Automated seeding for the optimization of crystal quality
Authors: Khurshid Sahir , Haire Lesley F. , Chayen Naomi E.
Published: June 2010

With the advent of structural genomics a variety of crystallization techniques have been automated and applied to high-throughput pipelines, yet seeding, which is the most common and successful optimization method, is still being performed predominantly manually. The aim of this study was to devise simple automated seeding techniques that can be applied in a routine manner using existing robots and not requiring special tools. Two alternative protocols for automated seeding experiments are described. One involves the delivery of microcrystals from stock to target wells using the robot dispensing tip as a seeding tool. The second harnesses an animal whisker as the seeding tool. Larger and better ordered crystals were obtained using both techniques.
ASTAR: a .NET class library for STAR/CIF manipulation
Authors: Lin Yun
Published: June 2010

A .NET class library for STAR/CIF manipulation, ASTAR, has been developed and is available at http://xstar.sourceforge.net/astar/. The library provides facilities to read and write STAR/CIF files and an object model to manipulate data in STAR/CIF files. While the library is written in the C# programming language, it can be utilized by programs written in various programming languages targeting the .NET platform.
Evidence of high sugar intake, and low fibre and mineral intake, in the gluten‐free diet
Authors: Wild D. , Robins G. G. , Burley V. J. , Howdle P. D.
Published: June 2010

Aliment Pharmacol Ther 2010; 32: 573–581

Background  The only therapy for coeliac disease (CD) is a long‐term gluten‐free diet (GFD). Little is known about the detailed composition of such a diet.

Aim  To clarify the nutritional composition of a GFD and to compare it with a non‐GFD diet in representative non‐CD populations.

Methods  A total of 139 consecutive patients with CD were invited to fill in a prospective validated 5‐day food diary, of whom data from 93 were analysed. Results were compared with data from the National Diet and Nutrition Survey of Adults and the UK Women’s Cohort Study (UKWCS).

Results  Individuals consuming a strict GFD generally had similar intakes of energy and nutrients to those of comparison populations, but a higher proportion of carbohydrate intake was obtained from nonmilk extrinsic sugars and intakes of nonstarch polysaccharides were low. Compared with the UKWCS sample, female patients adhering to a GFD had lower intakes of magnesium, iron, zinc, manganese, selenium and folate. In male patients, intakes of magnesium and selenium were particularly low.

Conclusions  This study reinforces the need for clinicians to recognize that avoidance of gluten cannot be the sole focus of a gluten‐free diet. Maintenance of adequate intakes of essential nutrients and in particular complex carbohydrates must also be the goal for patients.
Trauma history and risk of the irritable bowel syndrome in women veterans
Authors: White D. L. , Savas L. S. , Daci K. , Elserag R. , Graham D. P. , Fitzgerald S. J. , Smith S. L. , Tan G. , El‐Serag H. B.
Published: June 2010

Aliment Pharmacol Ther 2010; 32: 551–561

Background  Over 1.8 million women in the U.S. are veterans of the armed services. They are at increased risk of occupational traumas, including military sexual trauma.

Aim  To evaluate the association between major traumas and irritable bowel syndrome among women veterans accessing Veteran Affairs (VA) healthcare.

Methods  We administered questionnaires to assess trauma history as well as IBS, post‐traumatic stress disorder (PTSD) and depression symptoms to 337 women veterans seen for primary care at VA Women’s Clinic between 2006 and 2007. Logistic regression was used to evaluate the association between individual traumas and IBS risk after adjustment for age, ethnicity, PTSD and depression.

Results  Irritable bowel syndrome prevalence was 33.5%. The most frequently reported trauma was sexual assault (38.9%). Seventeen of eighteen traumas were associated with increased IBS risk after adjusting for age, ethnicity, PTSD and depression, with six statistically significant [range of adjusted odds ratios (OR) between 1.85 (95% CI, 1.08–3.16) and 2.6 (95% CI, 1.28–3.67)]. Depression and PTSD were significantly more common in IBS cases than controls, but neither substantially explained the association between trauma and increased IBS risk.

Conclusions  Women veterans report high frequency of physical and sexual traumas. A lifetime history of a broad range of traumas is independently associated with an elevated risk of the irritable bowel syndrome.