bluuebunny/crossref_metadata_2025 huggingface dataset:
Operationalizing Psychic Distance: A Revised Approach
Authors: Brewer Paul A.
Published: February 2007

Psychic distance, as described in the Uppsala internationalization model, is based on the impediments to information flows between a country market and a firm. The greater the impediments, the longer is the distance. The operationalization of psychic distance in empirical investigations is most commonly accomplished through the estimation of perceived “differences” between countries because it is argued that differences account for impediments to knowledge flows. However, this process is highly flawed. This article responds to the many calls for an improvement in the understanding and operationalization of psychic distance. It does so not only by holding to the original definition but also by accounting for wider measures than the differences between the firm's home country and the target country. The author identifies 15 variables from the literature and discusses the relationship between the variables and psychic distance. Using these variables, he constructs an index that measures psychic distance and then applies it to measure distances between 25 country combinations. Finally, he compares the results with actual exporter behavior. A close, negative correlation exists between the psychic distance index and firms’ actual selection of export markets.
Norms- and Control-Based Governance of International Manufacturer–Distributor Relational Exchanges
Authors: Gençtürk Esra F. , Aulakh Preet S.
Published: February 2007

This study contributes to an understanding of plural forms of governance by integrating research on norms-based and control-based mechanisms in managing interorganizational relationships. The authors develop a model of structural antecedents and performance consequences of these two distinct governance forms. Based on data from 129 relationships between U.S. manufacturers and foreign-based independent distributors, the empirical results show a differential effect of relationship structures on the use of control-based and norms-based governance. Furthermore, the results show that these governance forms have distinct performance implications, and the nature of their influence on the effectiveness of the relationship varies by the environmental uncertainty in the foreign markets.
Vapor-phase diethyl oxalate pretreatment of wood chips: Part 2. Release of hemicellulosic carbohydrates
Authors: Kenealy William , Horn Eric , Davis Mark , Swaney Ross , Houtman Carl
Published: February 2007

Wood chips of pine, spruce, aspen, and maple were treated at 135–140°C with diethyl oxalate (DEO) and analyzed for extractable and residual carbohydrates. Under these conditions, DEO hydrolyzes to ethanol and oxalic acid (OA). The amount and identity of carbohydrates released from the chips were species-dependent. For all wood species, increasing the amount of chemical, time, or temperature resulted in an increment in carbohydrates released. Approximately 50% (by wt) of extracted carbohydrates were monosaccharides. In addition, acetic acid was detected in the water extracts. When extracts were subsequently alkaline-treated, more acetate was released, indicating the presence of acetyl esters. The composition of water extracts and of wood chips after treatment indicates that these treatments primarily affect hemicelluloses. In summary, treatment of wood chips with DEO or OA releases carbohydrates suitable for fermentation, with no evidence of cellulose degradation.
Sap-staining fungi from logs and boards of two commercially important pines in Korea
Authors: Kim Gyu-Hyeok , Kim Jae-Jin , Breuil Colette
Published: February 2007

To collect more information about the organisms causing sap-stain, a thorough survey was conducted in Koreas sawmills that process logs and boards of Japanese red pine and Korean pine. Sap-staining fungi were isolated and identified using morphological and molecular methods. The 482 isolates obtained were distributed into at least nine species of ophiostomatoid fungi. In both pine species, the frequency of ophiostomatoid isolates was much higher in boards than in logs. Three species, Ophiostoma koreanum,O. floccosum, andO. piliferum, were found on both logs and boards. TwoPesotumspecies from Japanese red pine were isolated only from logs. Our results show that the dominant species in both logs and boards wasO. koreanumfrom Korean pine. However,O. koreanum,O. floccosum, andO. ipswere the most frequently found species in this study.
Laboratory and outdoor water repellency and dimensional stability of southern pine sapwood treated with a waterborne water repellent made from resin acids
Authors: Schultz Tor P. , Nicholas Darrel D. , Ingram Leonard L.
Published: February 2007

A major consumer concern regarding lumber in above-ground exposure such as decking is the poor dimensional stability that leads to warping, splitting, and checking. One method to increase dimensional stability is to treat lumber with a water repellent. A waterborne water repellent made from the resin acid abietic acid or a commercial source of resin acids, tall oil rosin or TOR, was tested using southern pine sapwood. In laboratory water-swelling tests, the waterborne abietic acid provided water repellency that was almost equivalent to that provided by wax, while no water repellency was observed with solventborne resin acid. Wood treated with waterborne TOR also provided good water repellency in laboratory tests and fair water repellency at up to 13 months of outdoor exposure, but the laboratory efficacy was partially reduced by a water leach. The dimensional stability (cupping and checking) and mold growth on TOR-treated lumber in above-ground exterior exposure was better than for untreated boards, but not as good as for wax-treated lumber. Analysis of the wood in southern pine tree trunks of 14 or 29 years of age of various diameters and sampled at the bottom, middle and top showed that the resin acid content in southern pine wood is quite variable. This may explain the wide variation in natural water repellency and decay resistance previously observed with untreated southern pine sapwood.
Yield and excitation function measurements of some nuclear reactions on natural thallium induced by protons leading to the production of medical radioisotopes201Tl and203Pb
Authors: Al-Saleh F. S. , Al-Harbi A. A. , Azzam A.
Published: February 2007

Excitation functions for201Pb,202mPb,203Pb and204mPb radionuclides which are formedviaproton induced reactions with natural thallium target have been measured from their respective threshold (Ethr) to 27.5 MeV using activation technique. Natural copper foils were used to monitor the cyclotron beam. The integral yields (MBq/μA h) of the produced radionuclides were calculated from the measured excitation functions. The optimum proton energy range for the production of203Pb with low amount of impurities is (16–10 MeV) after 5 h of EOB. The experimental cross-sections fornatTl(p,xn) reactions were compared with the cross-sections recommended by the IAEA and with earlier published data when it was possible.
Complexation of uranium(VI) with aromatic acids in aqueous solution – a comparison of hydroxamic acids and benzoic acid
Authors: Glorius Maja , Moll Henry , Bernhard Gert
Published: February 2007

The complex formation of uranium(VI) with salicylhydroxamic,benzohydroxamic, and benzoic acid in 0.1 M NaClO4 was studied by UV-vis spectroscopy at pH 3 and 4. Uranium(VI) species of the type M
p
L
q
H
r
were identified from the UV-vis spectra in all three systems. An increase in the absorption combined with a blue shift of the absorption maxima in comparison to the bands of the free uranyl ion of 22.5 ± 2 nm was observed in the uranium (VI)-salicylhydroxamic acid-system. Besides indications for a 1:2 complex, the formation of a 1:1 complex with a stability constant of log β111 = 17.12 ± 0.10 could be demonstrated by its individual absorption spectrum and molar absorption coefficient. Also in the uranium(VI)-benzohydroxamic acid-system a blue shift of the absorption maxima in comparison to the bands of the free uranyl ion of 27 ± 1.4 nm indicate the complex formation. The stability constants are log β110 = 7.96 ± 0.05 for UO2[C6H4CONHO]+ and log β120 = 15.25 ± 0.11 for UO2[C6H4CONHO]2. In contrast to the hydroxamic acids, benzoic acid shows a red shift of the absorption maxima of 2.5 ± 2 nm. Only the 1:1 complex UO2[C6H4COO]+ with a stability constant of log β110 = 3.37 ± 0.14 is existent. An estimate is made in order to discuss the dependencies observed in the absorption spectra in relation to possible coordination modes of uranium(VI). The strength of the complex formation between uranyl and the three aromatic acids is discussed.
N,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide impregnated magnetic particles for the uptake of lanthanides and actinides from nuclear waste streams
Authors: Shaibu B. S. , Reddy M. L. P. , Murali M. S. , Manchanda V. K.
Published: February 2007

A novel, simple technique based on magnetically assisted chemical separation (MACS) has been developed for the uptake of lanthanides and actinides from pure nitric acid solutions as well as from Simulated Pressurized Heavy Water Reactor-High Level Waste (PHWR-SHLW). Uptake profiles of various metal ions, such as Pu(IV), U(VI), Th(IV), Am(III), Eu(III), Sr(II), Cs(I) and Fe(III) were investigated as a function of time and nitric acid concentrations usingN,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide (TODGA) impregnated magnetic particles and compared withN,N′-dimethyl-N,N′-dibutyl tetradecyl malonamide (DMDBTDMA) and trialkyl phosphine oxide coated magnetic particles and also with TODGA coated extraction chromatographic resins. The uptake of various metal ions follows the order Eu(III) > Am(III) > Th(IV) > Pu(IV) > U(VI) > Sr(II) > Fe(III) > Cs(I) in pure nitric acid solutions. On the other hand, distinctly high distribution coefficient (Kd) value has been observed for Pu(IV) as compared to Eu(III) and Am(III) in SHLW. Further, no significant extraction of Cs(I) or Sr(II) was observed in SHLW. Also, at any acidity theKdvalue of a given metal ion is less in the SHLW as compared to that in pure HNO3, apparently due to the co-extraction of the other metal ions present in SHLW. The loading capacity of the TODGA impregnated magnetic particles with respect to Th(IV), U(VI) and Eu(III) was determined, along with the distribution isotherms to simulate multiple contacts. The adsorption models of Langmuir and Freundlich were fitted to the experimental data and best correlations was obtained for Langmuir model suggesting monolayer adsorption is the prevalent mechanism. The stability and reusability of the TODGA coated magnetic particles was also assessed.
A new time-resolved laser-induced fluorescence spectrometry (TRLFS) data acquisition procedure applied to the uranyl-phosphate system
Authors: Bonhoure Isabelle , Meca Sandra , Marti Vincenc , Pablo Joan de , Cortina Jose-Luis
Published: February 2007

TRLFS has been used to study the UVIO2
2+-PO4
3- system, in the 1 to 5 pH range, for [PO4
3-] = 2 × 10-3 to 1.02 × 10-1 M range and [UO2
2+] = 1.2 × 10-5 M. The data acquisition procedure was based on four different sets of acquisition parameters, which were chosen in order to maximize the fluorescence signal for four different time domains. The fitting procedure used to simulate the corresponding fluorescence decays curves was based on the crosscheck of the fitting results and on the inter-comparison between results for solutions of different concentrations. Five different lifetimes τ1 to τ5 were evidenced and associated with five uranyl species (UO2(H2PO4)2, UO2H2PO4
+, UO2HPO4, UO2PO4
- and UO2
2+). The fitting results, moreover, allowed the distinction between mono-, bi- and tri-exponential fluorescence decay behaviours. The isolated fluorescence spectra showed an expected wavelength shift between the fluorescence spectra of all the complexes, except in the case of the (UO2(H2PO4)2, UO2H2PO4
+) couple, which spectra were not distinguishable. Finally, the obtained results have shown that the data acquisition and fitting procedure enabled a complete and reliable characterization of the studied solutions.
Kinetics of isotopic exchange between calcium molybdate and molybdate ions in aqueous solution
Authors: Atun G. , Bodur N. , Ayyildiz H. , Ayar N. , Bilgin B.
Published: February 2007

The heterogeneous isotopic anion exchange kinetics and equilibria between calcium molybdate and sodium molybdate solutions have been studied by using 99Mo as tracer in batch experiments. The values of exchange ratio lower than unity suggest that rate-limiting step is particle diffusion process and the effect of re-crystallization can be neglected. The self-diffusion coefficients calculated using both Paterson´s and Nernst–Plank approximations are increased by the temperature. The observed values for isotope exchange characteristics such as exchange fractions, exchanging amounts and fractional attainment of equilibrium are consistent with those of their calculated values. Activation energy and thermodynamic parameters calculated based on transition state theory indicate the existence of both energy and entropy barrier in the system.
Whole Powder Pattern Modelling of cubic metal powders deformed by high energy milling
Authors: Scardi Paolo , Leoni Matteo , D'Incau Mirco
Published: February 2007

A Whole Powder Pattern Modelling of the diffraction pattern has been used to study the effect of grinding on some cubic metal powders: crystalline domain size distribution, unit cell parameter average dislocation density, effective outer cut-off radius, effective (screw-edge) dislocation character and faulting probabilities provide a detailed picture of the microstructure of heavily deformed metals. Besides proving the effectiveness of the analytical approach, the present study also suggests some generalization in the behaviour of pure powders of cubic metals subjected to an extensive high-energy milling.
Neutron diffraction studies of the atomic thermal vibrations in complex materials: application of the Wilson method to examination of micro- and nano-crystalline SiC
Authors: Stelmakh Svitlana , Grzanka Ewa , Wojdyr Marcin , Proffen Thomas , Vogel Sven C. , Zerda T. Waldek , Palosz Witold , Palosz Bogdan
Published: February 2007

The Wilson method was applied for determination of the thermal atomic motions in micro- and nano-crystalline SiC. Limitations of application of this method to examination of complex materials with atoms vibrating with more that one amplitude were discussed. It is shown that a unique interpretation of Wilson plots for crystals with more than one type of atoms and weak vibration component(s) requires measurements performed up to a very large diffraction vector Q (>25 Å–1). Atomic vibrations in microcrystalline SiC were evaluated based on the diffractograms calculated for models built assuming different mean square atomic displacements (vibration amplitudes) of the component atoms. For nanocrystalline SiC two different temperature atomic factors which describe vibrations of the atoms in the grain interior (B
core) and at its surface (B
shell) were determined.
Using X-ray powder diffraction and principal component analysis to determine structural properties for bulk samples of multiwall carbon nanotubes
Authors: Oddershede Jette , Nielsen Kurt , Stahl Kenny
Published: February 2007

It has been attempted to derive the structural properties of bulk multiwall carbon nanotubes (MWCNTs) from a combination of powder diffraction and principal component analysis (PCA). By a transformation of the direct PCA basis functions to a structural parameter set it was possible to obtain average values of inner radius, number of turns and d-spacing. The true tube lengths cannot be correctly estimated due to correlations to other properties, tube bending and defects in the tubes. Improvements can be expected by including distributions of the structural properties, further developing the functional relationships between the PCA and parameter functions and including the chiral angle (rolling direction) as a separate parameter.
Preferred crystallographic orientation in mature and juvenile wood
Authors: Bonarski Jan T. , Olek Wieslaw
Published: February 2007

Investigations of the crystallograpically organized regions of mature and juvenile Scots pine wood were performed. Experimental methods of X-ray diffraction were applied. Incomplete pole figures were measured, in order to calculate the orientation distribution function. The differences in the texture of the mature and juvenile wood were determined. The traditional concept of the mean microfibril angle was enhanced by developing the misorientation parameters. Evident differences in the space arrangement of cellulose of the both zones of wood were identified and described.
Synthesis and Assembling of Semiconductor and Metal Nanocrystals
Authors: Gaponik N. , Shavel A. , Lu L. , Eychmüller Alexander
Published: February 2007

The synthesis of strongly luminescing semiconductor nanocrystals reported is based on a wet-chemical approach. The use of aqueous solutions and the avoiding of dangerous and unstable precursors make this synthetic approach to be easily up-scaleable. The reaction yields are approaching gram amounts of the dried product and are limited solely by the laboratory facilities and thus may be further increased by using industrial equipments. The nanocrystals obtained by this route are strongly luminescing and suitable for various assembling procedures allowing the creation of core-shell spherical and thin-film composites, that are promising for photonic and optoelectronic applications. New assembly procedures allowing template-based formations of different types of metal-dielectric and porous metal nanostructures are presented.
Primary Processes During the Photodeposition of Ag Clusters on TiO2 Nanoparticles
Authors: Friedmann Donia , Hansing Heinrich , Bahnemann Detlef
Published: February 2007

In-situ transient laser flash photolysis absorption studies were carried out on transparent colloidal TiO2 suspensions in the presence of Ag+ ions and polyvinyl alcohol irradiated by an XeF laser (351nm wavelength) to investigate the early stages of Ag photodeposition on the TiO2 nanoparticles in the nanosecond and millisecond timescales. Photon fluxes of 5 × 10-5 and 1 × 10-6 mol photon/L were used; these were equivalent to approximately 60 and 2 photons/TiO2 particle, respectively. Metallic silver clusters were detected immediately after the laser pulse using both photon fluxes, with calculated quantum yields of 0.3 and 0.5, respectively. In both cases, the metallic silver clusters formed had the same characteristic absorption maxima, assigned to silver clusters containing ≥12 silver atoms. The formation of these larger than expected silver clusters, even at low photon fluxes, is believed to be a result of an electron transfer within the TiO2 aggregates, similar to an antenna effect. It is proposed that the silver deposits form an Ohmic contact on the TiO2 particle thus allowing the continuous electron transfer through the metallic silver nuclei and hence the further reduction of adsorbed Ag+ ions. This study reports the first observation of an antenna type effect for a photocatalytic reduction reaction.
Cobalt-Doped ZnO Nanorods Fabricated by a Simple Wet Chemical Route in Alcoholic Solution
Authors: Büsgen Thomas , Hilgendorff Michael , Giersig Michael
Published: February 2007

The synthesis of ZnO:Co nanorods in 1-butanol using a simple hydrolysis and condensation method under normal atmosphere is shown. The rods have average diameters of about 20nm and length up to 150nm. By doping with cobalt, the one-dimensional growth is retained due to the assistance of ethylene diamine as a ligand. Using energy dispersive X-ray analysis, it is proven that Co cations are incorporated into the ZnO host lattice only when the metal precursors are added slowly to a KOH solution at elevated temperatures. The visible defect-related luminescence of ZnO is suppressed by the dopant ions on the nanoparticle surfaces.
Formation of the Silver Hydride Ion AgH+ upon the Reduction of Silver Ions by H· in Aqueous Solution. A Pulse Radiolysis Study
Authors: Sarkar A. , Janata E.
Published: February 2007

The reaction of hydrogen atoms and of alcohol radicals with monovalent silver ions is studied in aqueous solution by means of pulse radiolysis. In acidic aqueous solutions containing silver ions and an alcohol, hydrogen atoms react with silver ions to form AgH+ with a rate constant of k=1.5 × 1010dm3mol-1s-1. This complex dissociates into free silver atoms and hydrogen ions with a first order rate constant of 2 × 107s-1. A reaction of alcohol radicals with silver ions could not be observed in aqueous solutions containing either methanol, ethanol or 2-propanol during times of up to 15ms; the rate constant would therefore have to be smaller than 1 × 104dm3mol-1s-1.
An Electrochemical Model for Gold Colloid Formation via Citrate Reduction
Authors: Rodríguez-González Benito , Mulvaney Paul , Liz-Marzán Luis M.
Published: February 2007

The mechanism of nanoparticle formation during the reduction of HAuCl4 with sodium citrate under reflux has been studied. We have found that the redox potential in the nucleating colloid remains very positive, around +0.75V vs. Ag/AgCl, until the reaction is almost complete. It then shifts suddenly to around +0.1V vs. Ag/AgCl at the end of the reaction, which is close to the final open-circuit potential in the sol. AuCl4
- continues to be reduced slowly over the course of the reaction, but is suddenly depleted as the potential shifts near the end of the reaction. The change in potential is correlated to the peptization of aggregates to form the final monodisperse gold particles. There is also a blue-shift of the surface plasmon band associated with charging of the gold particles.
Jacobi conjugate expansions
Authors: Stempak Krzysztof
Published: February 2007

We define and investigate the conjugacy operator for expansions with respect to the orthonormalized Jacobi polynomials. A general transplantation theorem for Jacobi series proved by Muckenhoupt is then applied to obtain weighted norm inequalities for conjugate Jacobi series.
On L1 convergence of Fourier series of complex valued functions
Authors: Le R. , Zhou S.
Published: February 2007

In the present paper we give a brief review of
L1
-convergence of trigonometric series. Previous known results in this direction are improved and generalized by establishing a new condition.
Existence to singular discrete boundary value problems with sign changing nonlinearities using approximation methods
Authors: Lü Haishen , O’Regan Donald , Agarwal Ravi
Published: February 2007

In this paper we use approximation methods to examine the singular discrete boundary value problem \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\left\{ \begin{gathered} - \Delta ^2 u(k - 1) = g(k,u(k)) + h(k,u(k)),k \in [1,T] \hfill \\ u(0) = 0 = u(T + 1) \hfill \\ \end{gathered} \right.$$
\end{document} where our nonlinearity may be singular in its dependent variable and is allowed to change sign.
Uniformly summable double sequences
Authors: Patterson Richard , Savaş Ekrem
Published: February 2007

In 1945 Brudno presented the following important theorem: If
A
and
B
are regular summability matrix methods such that every bounded sequence summed by
A
is also summed by
B
, then it is summed by
B
to the same value. In 1960 Petersen extended Brudno’s theorem by using uniformly summable methods. The goal of this paper is to extend Petersen’s theorem to double sequences by using four dimensional matrix transformations and notion of uniformly summable methods for double sequences. In addition to this extension we shall also present an accessible analogue of this theorem.
Effects of Angling on Chinook Salmon for the Nicola River, British Columbia, 1996–2002
Authors: Cowen Laura , Trouton Nicole , Bailey Richard E.
Published: February 2007

To sustain viable fish populations, protect stocks of wild salmon Oncorhynchus spp., and successfully manage the Pacific salmon fishery, all sources of fishing mortality need to be understood. The fishery targeting Chinook salmon O. tshawytscha is an important component of the commercial, recreational, and First Nations fisheries in British Columbia. A mark–recovery study was used to investigate the effect of angling on both the immediate hooking mortality and subsequent spawning success of Chinook salmon in the Nicola River, British Columbia, from 1996 to 2002. The immediate hooking mortality rate was lower than mortality rates reported for marine and other freshwater fisheries. Higher hooking mortality rates were found for fish hooked in critical locations, which were associated with heavy bleeding. However, increased bleeding did not translate into reduced spawning success for those fish that survived. Conclusions regarding hook size and its association with hooking mortality rate and spawning success remain unclear. Using optimal techniques and under the right conditions, catch-and-release angling can be an effective conservation and management tool.
An analytical investigation of thermal prestressing method for continuous composite girder bridges
Authors: Kim S. H. , Kim J. H. , Ahn J. H. , Song H. W.
Published: February 2007

The negative bending moment near the intermediate supports of continuous composite girder bridges induces tensile stresses in the concrete deck. Although a relatively high ratio of reinforcement is present in these regions, tensile cracks are repeatedly reported. The tensile cracks rapidly deteriorate the concrete deck, giving rise to frequent need for maintenance work. Also owing to the tensile stresses, the concrete deck sections at the negative bending moment regions are ignored in the design process and this kind of design concept is a huge drawback regarding effective use of materials. Prestressing methods are usually utilised in this kind of situation for the concrete structures, but no effective and feasible method has yet been proposed for steel–concrete composite structures. In the current study, a new type of prestressing method entitled the thermal prestressing method (TPSM) is proposed for the innovative construction of continuous composite girder bridges. Basic concepts of the TPSM are introduced and a methodology for computing the TPSM effect is presented with illustrative examples.
An experimental investigation of thermal prestressing method for continuous composite steel girder bridges
Authors: Kim S. H. , Kim J. H. , Ahn J. H. , Song H. W.
Published: February 2007

This paper describes an experimental investigation conducted to verify and substantiate the preceding analytical study, which was focused on the development of the thermal prestressing method (TPSM) including the basic concepts of the method and the methodology for numerical analysis of the thermal prestressing effect. The experimental results from this research, especially the initial stress measurement from a prototype bridge, prove that the method can be successfully used for prestressing continuous composite girder structures. Also, the experimental and analytical results exhibit good agreement, which implies that the thermal prestressing effect can be predicted with reasonable accuracy with the previous proposed methodology. It is concluded that the TPSM can be successfully applied to both the design and construction of continuous composite girder structures, and the authors are optimistic about the TPSM becoming an innovative solution for prestressing continuous composite girder bridges.
Seismic performance of lap-spliced columns with glass FRP
Authors: Youm K.-S. , Lee Y.-H. , Choi Y.-M. , Hwang Y.-K. , Kwon T.-G.
Published: February 2007

The present paper represents experimental studies on the seismic performance of reinforced concrete circular columns with lap-splice details using glass fibre reinforced polymer (FRP) wrapping. Five full-scale model columns of 1200 mm diameter and 6550 mm height were classified into one column with no lap-splice, one column with lap-splice and three glass FRP retrofitted columns with lap-splice; those models were conducted by quasi-static cyclic loading test. The prototype structure is an existing circular reinforced concrete bridge pier designed by the following pre-seismic codes and constructed in South Korea in 1979. The lap-spliced column was expected to have a brittle failure owing to the bond-slip of lap-spliced longitudinal reinforcement. The retrofitted columns using glass FRP wrapping showed a significant improvement of seismic performance and developed the stable hysteretic loops. However, from the strain gauge readings, the unyieldingness of lap-spliced longitudinal bars was observed regardless of glass FRP thickness. It is concluded that the displacement ductility factor cannot be defined owing to the unyieldingness of longitudinal bar and the estimated displacement ductility factor should be introduced in order to evaluate the performance of the columns with lap-spliced longitudinal bars. Glass FRP retrofit design methods suggested by other researchers were verified in the experiment and a new modified design method was proposed.
Successive Paleocene and Eocene infillings of polyphase paleokarsts within the Cretaceous limestones of the Empordà thrust sheets (Catalan Pyrenees, Spain) : relationships between tectonics and karstification
Authors: Peybernès Bernard , Fondecave-Wallez Marie-José , Combes Pierre-Jean , Seranne Michel
Published: February 2007

The Mesozoic series of the southern units of the Pyrenean Empordà thrust sheets (Montgrí and Figueres nappes, Catalonia, Spain) were finally emplaced over the autochthonous basement and its Cenozoic cover during Eocene times. However, they have originally been folded by the “Laramian” compressional event (Late Cretaceous/Early Paleocene), while they were still in their root zone more than 50 km to the N-NE. Postdating the Santonian, the emersion of the Cretaceous tectorogen induced karst formation at the expense of Berriasian to Santonian limestone sequences. Karst cavities of this paleokarst 1 (lapiaz and canyons) were subsequently coated with a fine, red or black, Microcodium-bearing, continental silt, and infilled with marine chaotic breccias. Following a new episode of emersion then erosion, the original paleokarst 1 was cross-cut by newly formed cavities of the paleokarst 2, filled with Lutetian-Bartonian marine breccias. Both types of marine breccias (Paleocene then Eocene in age) are now relatively well dated by means of planktonic foraminifera (Globigerinacea) occurring within the argillaceous-sandy matrix, and for the older ones, within the argillaceous-sandy or carbonate, finely laminated, interbedded hemipelagites, that mark the top of marine sequences tens of centimetres thick. The relationships of the “Laramian” and “Pyrenean” compressional tectonic events, occurring from latest Cretaceous to Bartonian, with the development of paleokarsts 1 and 2 are analysed in the perspective of the progressive southwards emplacement of the Montgrí thrust sheet, during Eocene time.
The Rhode Island Lead Paint Lawsuit: Where do We Go from Here?
Authors: Rabin Rick
Published: February 2007

Reports of child lead poisoning from paint date back over a hundred years. The lead paint companies were well aware of that hazard long before they ceased the sale of lead paint. Throughout the 20th century there was a gradually increasing acknowledgment by public health officials of the need to remove lead paint from the environment of young children, but minimal public resources were made available to do so. Beginning in the 1980s, lawsuits were filed against the industry; however, for legal/technical reasons, none was successful until a Rhode Island jury held that three former paint manufacturers had knowingly created a “public nuisance.” Consequently, ongoing and future lawsuits may yield the resources for an end to child lead poisoning.
ILO to Promote Global Asbestos Ban
Authors: O'Neill Rory
Published: February 2007

The International Labour Office (ILO) is to pursue a global ban on asbestos, the world's biggest ever industrial killer. The landmark decision came with the adoption of a resolution on 14 June 2006 at the ILO conference in Geneva and followed a high level union campaign. Rory O'Neill asked Jukka Takala, director of ILO's SafeWork program, what ILO will now do to help make the world asbestos-free.
Green Chemistry in California: A Framework for Leadership in Chemicals Policy and Innovation
Authors: Wilson Michael P. , Chia Daniel A. , Ehlers Bryan C.
Published: February 2007

This article summarizes a University of California chemicals policy report commissioned by the California Legislature. The report makes the case that long-standing weaknesses in the Toxic Substances Control Act have produced a flawed chemicals market in the U.S. that “undervalues” the hazardous properties of chemicals relative to their function, price, and performance. These market conditions have dampened industry interest in cleaner chemical technologies, such as green chemistry. A new U.S. chemicals policy will need to improve the flow of chemical information; enhance the capacity of government to control chemical hazards; and increase public investments in green chemistry research and education.
Adolescent Grief: Relationship Category and Emotional Closeness
Authors: Servaty-Seib Heather L. , Pistole M. Carole
Published: February 2007

Bereaved adolescents ( N = 90) who had experienced relatively common death losses (e.g., grandparent, friend) completed the Texas Revised Inventory of Grief and the Emotional Closeness Scale and Continuum. Results indicated that present grief was significantly higher for friend than for grandparent death loss. A MANOVA revealed that those in the high closeness group reported significantly higher mean scores on past and present grief than those in the low closeness group. Finally, in a hierarchal multiple regression, after demographic variables were entered (e.g., age, present at death), emotional closeness added significant variance to the prediction of past and present grief. This research contributes to the understanding of grief intensity following adolescents' most common death losses and highlights the importance of counselors' intentionally and directly assessing bereaved adolescents' perceived emotional closeness to the deceased as part of grief-related counseling.
Living beyond the Unanticipated Sudden Death of a Partner: A Phenomenological Study
Authors: Rodger Martin L. , Sherwood Patricia , O'Connor Moira , Leslie Gavin
Published: February 2007

This research project explored grief and its impact upon men and women who have experienced the sudden and unanticipated death of his or her partner.

It included what grief meant to them, how it was manifested in his or her everyday lives and how his or her partner's death had impacted upon his or her relationship with themselves, with others and the world. A Husserlian phenomenological approach was used to explore the experiences of the ten women and five men whose partner had died up to five years prior to being interviewed. The need for the surviving partner to continue to participate in everyday life placed great strain upon the internal resources of the surviving partner. The surviving partner needed to reinvent him or herself, in an attempt to become independent and regain functionality, whilst dealing with the sadness and loss that they had experienced. The surviving partner discovered that a new life order emerged that included hope, optimism, planning for the future and perhaps the prospect of a new relationship. The death of a partner left the surviving partner with a loss that would always be a part of them, with the memories of his or her relationship being maintained within them that will never be replaced by somebody else. The results of this research project reinforce the need for ongoing education of the community in grief and bereavement issues in order to increase the awareness of the support needs of the bereaved person. The length of time and amount of energy required to incorporate the experience into the survivor's life, is greatly underestimated by the community, and perhaps by some of the health and caring professionals. Colonial and hospital based bereavement support services need to be established and be proactive using outreach programs, actively offering the suddenly bereaved partner and family support and information.
Universality of J-Shaped and U-Shaped Dose-Response Relations as Emergent Properties of Stochastic Transition Systems
Authors: Cox Louis Anthony (Tony)
Published: February 2007

Dose-response data for many chemical carcinogens exhibit multiple apparent concentration thresholds. A relatively small increase in exposure concentration near such a threshold disproportionately increases incidence of a specific tumor type. Yet, many common mathematical models of carcinogenesis do not predict such threshold-like behavior when model parameters (e.g., describing cell transition rates) increase smoothly with dose, as often seems biologically plausible. For example, commonly used forms of both the traditional Armitage-Doll and multistage (MS) models of carcinogenesis and the Moolgavkar-Venzon-Knudson (MVK) two-stage stochastic model of carcinogenesis typically yield smooth dose-response curves without sudden jumps or thresholds when exposure is assumed to increase cell transition rates in proportion to exposure concentration.

This paper introduces a general mathematical modeling framework that includes the MVK and MS model families as special cases, but that shows how abrupt transitions in cancer hazard rates, considered as functions of exposure concentrations and durations, can emerge naturally in large cell populations even when the rates of cell-level events increase smoothly (e.g., proportionally) with concentration. In this framework, stochastic transitions of stem cells among successive events represent exposure-related damage. Cell proliferation, cell killing and apoptosis can occur at different stages. Key components include:

An effective number of stem cells undergoing active cycling and hence vulnerable to stochastic transitions representing somatically heritable transformations. (These need not occur in any special linear order, as in the MS model.) A random time until the first malignant stem cell is formed. This is the first order-statistic, T = min{T1, T2, …, Tn} of n random variables, interpreted as the random times at which each of n initial stem cells or their progeny first become malignant. A random time for a normal stem cell to complete a full set of transformations converting it to a malignant one. This is interpreted very generally as the first passage time through a network of stochastic transitions, possibly with very many possible paths and unknown topology.

In this very general family of models, threshold-like (J-shaped or multi-threshold) dose-response nonlinearities naturally emerge even without cytotoxicity, as consequences of stochastic phase transition laws for traversals of random transition networks. With cytotoxicity present, U-shaped as well as J-shaped dose-response curves can emerge. These results are universal, i.e., independent of specific biological details represented by the stochastic transition networks.
Test of the Linear-No Threshold Theory: Rationale for Procedures
Authors: Cohen Bernard L.
Published: February 2007

A tightly reasoned justification is presented for the procedures used in our test of the linear-no threshold theory of radiation carcinogenesis by comparing lung cancer rates with average radon exposure in U.S. counties. A key point is its dependence on ecological variables rather than on characteristics of individuals and the principal problems involve treatment of potential confounding factors (CF). The method of stratification is introduced and shown to be preferable to multiple regression for evaluating effects of confounding. Utilizing numerous available CF reduces the problem of representing a complex confounding relationship by the average value of a single CF. The requirements on a CF for affecting the results are quantified in terms of its correlations with lung cancer rates and radon levels and it is shown that the existence of an unknown confounder satisfying these requirements is highly implausible. Effects of combinations of confounding factors are treated and shown not to be important. The problem of confounding factors on the level of individuals is resolved. Consideration of plausibility of correlations is used in several applications, including treatments of uncertainty in smoking prevalence, within county differences in radon exposure between smokers and non-smokers, variations in intensity of smoking, differences between measured radon levels and actual exposures, etc. Examples are presented for all applications. The differences between our study and case-control studies, and the advantages of each for testing the linear-no threshold theory, are discussed.
A Model of Cytotoxic Dose-Response Nonlinearities Arising from Adaptive Cell Inventory Management in Tissues
Authors: Cox Louis Anthony (Tony)
Published: February 2007

Why do low-level exposures to environmental toxins often elicit over-compensating responses that reduce risk to an organism? Conversely, if these responses improve health, why wait for an environmental challenge to trigger them? This paper presents a mathematical modeling framework that addresses both questions using the principle that evolution favors tissues that hedge their bets against uncertain environmental challenges. We consider a tissue composed of differentiated cells performing essential functions (e.g., lung tissue, bone marrow, etc.). The tissue seeks to maintain adequate supplies of these cells, but many of them may occasionally be killed relatively quickly by cytotoxic challenges. The tissue can “order replacements” (e.g., via cytokine network signaling) from a deeper compartment of proliferative stem cells, but there is a delivery lag because these cells must undergo maturation, amplification via successive divisions, and terminal differentiation before they can replace the killed functional cells. Therefore, a “rational” tissue maintains an inventory of relatively mature cells (e.g., the bone marrow reserve for blood cells) for quick release when needed. This reservoir is replenished by stimulating proliferation in the stem cell compartment. Normally, stem cells have a very low risk of unrepaired carcinogenic (or other) damage, due to extensive checking and repair. But when production is rushed to meet extreme demands, error rates increase. We use a mathematical model of cell inventory management to show that decision rules that effectively manage the inventory of mature cells to maintain tissue function across a wide range of unpredictable cytotoxic challenges imply that increases in average levels of cytotoxic challenges can increase average inventory levels and reduce the average error rate in stem cell production. Thus, hormesis and related nonlinearities can emerge as a natural result of cell-inventory risk management by tissues.
Hormetic Modulation of Aging and Longevity by Mild Heat Stress
Authors: Rattan Suresh I. S.
Published: February 2007

Aging is characterized by a stochastic accumulation of molecular damage, progressive failure of maintenance and repair, and consequent onset of age-related diseases. Applying hormesis in aging research and therapy is based on the principle of stimulation of maintenance and repair pathways by repeated exposure to mild stress. In a series of experimental studies we have shown that repetitive mild heat stress has anti-aging hormetic effects on growth and various other cellular and biochemical characteristics of human skin fibroblasts undergoing aging in vitro. These effects include the maintenance of stress protein profiles, reduction in the accumulation of oxidatively and glycoxidatively damaged proteins, stimulation of the proteasomal activities for the degradation of abnormal proteins, improved cellular resistance to ethanol, hydrogenperoxide and ultraviolet-B rays, and enhanced levels of various antioxidant enzymes. Anti-aging hormetic effects of mild heat shock appear to be facilitated by reducing protein damage and protein aggregation by activating internal antioxidant, repair and degradation processes.
Doe Program—Developing a Scientific Basis for Responses to Low-Dose Exposures: Impact on Dose-Response Relationships
Authors: Brooks Antone L. , Couch Lezlie
Published: February 2007

The DOE Low Dose Radiation Research Program focuses on biological mechanisms involved in response to low doses of both low and high-LET radiation (<0.1Gy). This research program represents a merging of new technologies with cutting edge biological techniques associated with genomics. This merger enables observation of radiation-induced cellular and molecular changes previously undetectable. These low-dose responses define mechanisms of interaction of radiation with living systems, and characterize the shape of dose-response. The research from this program suggests radiation paradigms regarding the involvement of radiation in the carcinogenic process. New biological phenomena observed at low doses include initial radiation-induced DNA damage and repair, changes in gene expression, adaptive responses and bystander effects. However, information from this cellular-molecular level cannot be directly extrapolated to risks in human populations. Links must be carefully developed between dose-response relationships at the cell and tissue levels and risk to human populations. The challenge and the ultimate goal of the Program is to determine if basic scientific data can be combined with more traditional epidemiological methods to improve the estimation of radiation risk from low level radiation exposures.
Smoking and Hormesis as Confounding Factors in Radiation Pulmonary Carcinogenesis
Authors: Sanders Charles L. , Scott Bobby R.
Published: February 2007

Confounding factors in radiation pulmonary carcinogenesis are passive and active cigarette smoke exposures and radiation hormesis. Significantly increased lung cancer risk from ionizing radiation at lung doses < 1 Gy is not observed in never smokers exposed to ionizing radiations. Residential radon is not a cause of lung cancer in never smokers and may protect against lung cancer in smokers. The risk of lung cancer found in many epidemiological studies was less than the expected risk (hormetic effect) for nuclear weapons and power plant workers, shipyard workers, fluoroscopy patients, and inhabitants of high-dose background radiation. The protective effect was noted for low- and mixed high- and low-linear energy transfer (LET) radiations in both genders. Many studies showed a protection factor (PROFAC) > 0.40 (40% avoided) against the occurrence of lung cancer. The ubiquitous nature of the radiation hormesis response in cellular, animal, and epidemiological studies negates the healthy worker effect as an explanation for radiation hormesis. Low-dose radiation may stimulate DNA repair/apoptosis and immunity to suppress and eliminate cigarette-smoke-induced transformed cells in the lung, reducing lung cancer occurrence in smokers.