bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parallel coarse‐grid selection
Authors: Alber David M. , Olson Luke N. 
Published: July 2007

AbstractAlgebraic multigrid (AMG) is a powerful linear solver with attractive parallel properties. A parallel AMG method depends on efficient, parallel implementations of the coarse‐grid selection algorithms and the restriction and prolongation operator construction algorithms. In the effort to effectively and quickly select the coarse grid, a number of parallel coarsening algorithms have been developed. This paper examines the behaviour of these algorithms in depth by studying the results of several numerical experiments. In addition, new parallel coarse‐grid selection algorithms are introduced and tested. Copyright © 2007 John Wiley & Sons, Ltd.
State estimation in process tomography—Three‐dimensional impedance imaging of moving fluids
Authors: Seppänen A. , Vauhkonen M. , Vauhkonen P. J. , Voutilainen A. , Kaipio J. P. 
Published: July 2007

AbstractIn this paper, we consider three‐dimensional impedance imaging of rapidly varying objects. We especially concentrate on the case where the target is a moving fluid and the objective is to track the concentration distribution of a substance dissolved in the fluid. The observations are made as in ordinary electrical impedance tomography (EIT), but in the reconstruction we employ the convection–diffusion model to yield information on the temporal behavior of the object. The observation model of EIT together with the evolution model constitute the state‐space representation of the system, and the reconstruction problem of EIT can be described as a state estimation problem. The state estimation problem is solved using the Kalman filter and the fixed‐interval smoother algorithms. The performance of the state estimation approach is evaluated in a simulation study. Copyright © 2007 John Wiley & Sons, Ltd.
Blends of starch with ethylene vinyl alcohol copolymers: effect of water, glycerol, and amino acids as plasticizers
Authors: Orts William J. , Nobes Geoffrey A. R. , Glenn Gregory M. , Gray Gregory M. , Imam Syed , Chiou Bor‐Sen 
Published: July 2007

AbstractBlends of thermoplastic starch with poly(ethylene‐co‐vinyl alcohol) copolymer (EVOH) were melt extruded with water/glycerol as plasticizer and a series of amino acid additives. The biggest factor in end‐use mechanical properties proved to be the relative humidity (RH) during storage. Plasticized starch‐EVOH blends stored at 0 and 50% RH changed significantly over time, with, for example, the tensile strength (TS) of the glycerol‐plasticized blend increasing from 4.7 to 26.3 MPa over 8 weeks when maintained at 0% RH. In contrast, the TS of this same sample stored at 75% RH remained unchanged for 8 weeks. Amino acids provided relatively minor, but significant changes in mechanical properties with time. Based on TS, elongation‐to‐break, and modulus, it may be concluded that β‐alanine, sarcosine, and L‐proline were more effective than glycerol at maintaining strong flexible blends. Increases in crystallinity and changes in morphology with time, as described by modulated DSC were correlated to these changes in mechanical properties. Published in 2007 by John Wiley & Sons, Ltd.
Molecular basis of LFER: theoretical study of polar substituent effect in aliphatic series
Authors: Ponec Robert , Van Damme Sofie 
Published: July 2007

AbstractThe nature of inductive substituent effect on the gas phase acidity of several series of aliphatic carboxylic acids with rigid molecular skeletons was analyzed using the recently proposed quantum chemical approach based on the theory of proton affinity proposed by Longuet‐Higgins. The results of the analysis suggest that the substituent induced variation of the acidity is in all series due to electrostatic field‐effect which in the gas phase can reasonably be characterized by Kirkwood–Westheimer theory. Copyright © 2007 John Wiley & Sons, Ltd.
Ketene‐forming elimination reactions from aryl phenylacetates promoted by R2NH in MeCN: effects of base‐solvent and β‐phenyl group
Authors: Pyun Sang Yong , Seok Hyoun Jung , Kim Ju Chang , Kim Hwan Myung , Cho Bong Rae 
Published: July 2007

AbstractElimination reactions of C6H5C(R)HCO2C6H3‐2‐X‐4‐NO2 [R = H (1), Ph (2), X = H (a), Cl (b), NO2 (c)] promoted by R2NH in MeCN have been studied kinetically. The reactions are second‐order and exhibit Brönsted β = 0.46–0.89 and |βlg| = 0.37–0.76 and an E2 mechanism is evident. When the base‐solvent was changed from R2NH/R2NH–70 mol% MeCN(aq) to R2NH‐MeCN, β and |βlg| values remained nearly the same within experimental error. For eliminations from 1 and 2, β and |βlg| values were nearly identical, although the rate was retarded by the β‐Ph group. Noteworthy is the relative insensitivity of the ketene‐forming transition state to the base‐solvent and β‐R group variation. Copyright © 2007 John Wiley & Sons, Ltd.
Crystal structure of MtnX phosphatase from Bacillus subtilis at 2.0 Å resolution provides a structural basis for bipartite phosphomonoester hydrolysis of 2‐hydroxy‐3‐keto‐5‐methylthiopentenyl‐1‐phosphate
Authors: Xu Qingping , Saikatendu Kumar Singh , Krishna S. Sri , McMullan Daniel , Abdubek Polat , Agarwalla Sanjay , Ambing Eileen , Astakhova Tamara , Axelrod Herbert L. , Carlton Dennis , Chiu Hsiu‐Ju , Clayton Thomas , DiDonato Michael , Duan Lian , Elsliger Marc‐André , Feuerhelm Julie , Grzechnik Slawomir K. , Hale Joanna , Hampton Eric , Han Gye Won , Haugen Justin , Jaroszewski Lukasz , Jin Kevin K. , Klock Heath E. , Knuth Mark W. , Koesema Eric , Miller Mitchell D. , Morse Andrew T. , Nigoghossian Edward , Okach Linda , Oommachen Silvya , Paulsen Jessica , Reyes Ron , Rife Christopher L. , Schwarzenbacher Robert , van den Bedem Henry , White Aprilfawn , Wolf Guenter , Hodgson Keith O. , Wooley John , Deacon Ashley M. , Godzik Adam , Lesley Scott A. , Wilson Ian A. 
Published: July 2007

AbstractNo abastract.
Three‐dimensional holograph vector of atomic interaction field (3D‐HoVAIF): a novel rotation–translation invariant 3D structure descriptor and its applications to peptides
Authors: Tian Feifei , Zhou Peng , Lv Fenglin , Song Rong , Li Zhiliang 
Published: July 2007

AbstractQuantitative structure–activity relationship (QSAR) study, important in drug design, mainly involves two aspects, molecular structural characterization (MSC) and construction of a statistical model. MSC focuses on transforming molecular structural and property characteristics into a group of numerical codes, dedicated to minimizing information loss during this process. In this context, common atoms in organic compounds are classified according to their families in the periodic table, and hybridization states, and on the basis of these, three nonbonding interactions (i.e. electrostatic, van der Waals and hydrophobic) are calculated, ultimately resulting in a new rotation–translation invariant, 3D‐MSC, as a three‐dimensional holograph vector of atomic interaction field (3D‐HoVAIF). By applying 3D‐HoVAIF to QSAR studies on two classical peptides including 58 angiotensin‐converting enzyme (ACE) inhibitors and 48 bitter‐tasting dipeptides, we get two excellent genetic algorithm‐partial least squares (GA‐PLS) models, with statistics r2, q2, root mean square error (RMSEE), and root mean square error of cross‐validation (RMSCV) of 0.857, 0.811, 0.376, and 0.432 for ACE inhibitors and 0.940, 0.892, 0.153 and 0.205 for bitter‐tasting dipeptides, respectively. By equally dividing the two datasets into training and test sets by D‐optimal, the 3D‐HoVAIF approach undergoes rigorous statistical validation. Furthermore, the superior performance of 3D‐HoVAIF is confirmed in comparison with two other peptide MSC approaches referring to z‐scale and ISA‐ECI. For 58 ACE inhibitors, the GA‐PLS model yields two principal components, with the following statistics: r2 = 0.893, q2 = 0.824, RMSEE = 0.349, RMSCV = 0.425, $q_{\rm {ext}}^{2} = 0.739$, $r_{\rm {ext}}^{2} = 0.784$, $r_{0, {\rm {ext}}}^{2} = 0.781$, $r_{0, ext}^{'2} = 0.779$, k = 0.962, k′ = 1.019, and RMSEP = 0.460; for 48 bitter‐tasting dipeptides, three principal components resulted, with the statistics as: r2 = 0.950, q2 = 0.893, RMSEE = 0.152, RMSCV = 0.222, $q_{ext}^{2} = 0.875$, $r_{ext}^{2} = 0.919$, $r_{0, ext}^{2} = 0.919$, $r_{0, ext}^{'2} = 0.919$, k = 1.018, k′ = 0.974, and RMSEP = 0.198. In addition, the relationship of ACE‐inhibiting activities with bitter‐tasting thresholds has been investigated by applying the above‐constructed models to predictions on 400 theoretically possible dipeptides. Through analysis, the ACE‐inhibiting activities are found to be prominently related to bitter‐tasting intensities. Thus, it is deemed to be difficult to find such dipeptides that simultaneously satisfy pharmacodynamic action (high ACE‐inhibiting activities) and comfortable tastes, suggesting that active components of dipeptides that are served as functional food to lower blood pressure are not very ideal. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Topological Electronegativity Index and Its Application – I. Ionization Potentials of Alkyl Groups and Alkyl Halides
Authors: Cao Chenzhong , Luo Jinhua 
Published: July 2007

AbstractA Topological Electronegativity Index (TEI) for alkyl group was developed, based on the bond adjacency matrix of the radical atom. Taking the radical atom and the adjacency atoms (or groups) as the vertices of molecular graph of the alkyl group, the bond adjacency matrix was constructed, in which the diagonal elements were assigned the Pauling electronegativity of the atom (or group), and the off‐diagonal elements were assigned values 1 or 0. The off‐diagonal elements represent the bond connections: that is when the two atoms (or groups) connect with each other, it is 1; otherwise is 0. From the matrix, the eigenvalues were obtained and its geometric mean value was considered as the TEI of an alkyl. The calculated TEI has good correlation with its experimental ionization potential. Further, the TEI was applied to correlate with the ionization potentials of alkyl halides and substituted ethenes, and to correlate with the Bond Dissociation Energies (BDEs) of the CiH bonds in alkanes.
Success with improvement — requires the right roles to be enacted — in symbiosis
Authors: Johansen Jørn , Pries‐Heje Jan 
Published: July 2007

AbstractSuccess in process improvement (PI) depends on the viewpoint and the observer. The same process can be seen as a success from one viewpoint and an utter failure from another. In this article, we report the results of a large Danish research project that set out to study success and failure in product innovation and PI projects, using a large interview study and grounded theory analysis as the research approach. One main outcome of the research project was a model and a method — called ImprovAbility — that can be used to increase an organization's ability to succeed. Another outcome was detailed findings about the different roles in PI. The roles we identify are that of project members, project managers, process owners, project organization, top managers, involved experts and users. They all have different roles in relation to the organizational goal: improving and becoming better at improving. They are also involved in defining requirements and providing and obtaining knowledge in different ways, and they focus on different things, face different problems, and are happy about different solutions. The core of the article reports these findings and discusses how one can use diversity to increase the chance of success in PI. Copyright © 2007 John Wiley & Sons, Ltd.
Optimum design of multistory uniform structures with simple eccentricity
Authors: Georgoussis George K. 
Published: July 2007

AbstractA simple formula is presented to predict the conditions under which the degree of translational–torsional coupling of mixed‐bent‐type multistory eccentric buildings is insignificant and can be neglected in the structural design of such buildings. The formula is applicable to monosymmetric structures consisting of walls and rigid frames that are uniform over the height of the building. The derivation of the formula is based on the technique of representing discrete‐member structural models with an equivalent continuum medium and on the findings of an earlier paper presented by the writer, that in eccentric mixed‐bent‐type structures, under certain circumstances, the eccentricity of the wall system opposes the eccentricity of the frame system and that results in an effectively uncoupled building structure. The accuracy of the formula is examined by means of a parametric study that includes common types of wall‐frame monosymmetric structures and comparisons are made with the results obtained by three‐dimensional finite element dynamic analyses of discrete member models. Copyright © 2007 John Wiley & Sons, Ltd.
Structure and aggregation in dilate solution of surface active agents
Authors: Klevens H. B. 
Published: July 2007

SummaryCritical micelle concentrations (CMC) are shown to depend on chain length. All straight chain saturated surface active agents of equal ion length have approximately the same CMC. Thus a C13 fatty acid soap, a C12 sulfonate, a C11 sulfate, and a C12 ammonium chloride have CMC values of 0.010–0.014M. Values of CMC are not changed to any extent by substitution near the hydrophilic head of one, two, or three groups, even as large as hydroxyethyl, in place of the amine hydrogens in the cationic detergents. However substitution with dihydroxypropyl groups has a marked effect on association in C12 but not in the C16 series, indicating that the relative lengths of the two chains must be considered as an important factor in association. This is well illustrated in the dialkylsulfosuccinate series, and in a tetradecane sulfate series in which the −SO4Na group was progressively moved down the chain, particularly when the branched chain compounds are compared with the corresponding straight chain detergents of length equal to the maximum length from the charged head to the ultimate carbon atom. Introduction of double bonds causes a small but definite increase in CMC whereas polar substitution in the chain results in a marked increase in CMC. Possible micelle structures are discussed in the light of these association phenomena, and it is concluded that the assignment of a definite size and shape to micelles appears at the present time to be slightly premature. However if one includes the concept of relative order‐disorder in the micelle as one of the factors, in addition to chain length, type of detergent, and environment, which are important in micelle structure, it is possible to explain partially the apparent marked differences which have been reported for micelles of different surface active agents.
An inexpensive soap stock conversion plant
Authors: Levin Herman , Swearingen J. S. 
Published: July 2007

SummaryThe design of an inexpensive, small scale plant for converting soap stock to crude fatty acid has been described. It has a capacity for producing 6 tons of product (90–95 wt. % fatty acid) per day from 4,000 gallons of soap stock feed (35–40 wt. % fatty acid). Installed at a cost of $11,000, the unit investment has proved to range between $7 and $8 per annual ton of product. Operating continuously for the past two years since construction (at varying percentages of capacity), total processing costs have averaged 0.75c per pound of fatty acid product.This plant design is presented to demonstrate that a small scale and marginal operation, such as soap stock conversion, can be carried out both economically and competitively when preceded by sound engineering analysis.
Factor for converting elemental phosphorus to acetone insolubles in crude soybean oil
Authors: List G. R. , Heakin A. J. , Evans CD. , Black L. T. , Mounts T. L. 
Published: July 2007

AbstractThe official AOCS method CA 12‐55 contains a factor of 30 in an equation for relating the phosphorus content of crude soybean oil to equivalent phosphatide. The historical derivation of this factor is discussed. The mean value was calculated to be 31.7 ±0.9 by correlation of phosphorus content with acetone insolubles in six lots of crude oil.
Distribution of Na+/I– Symporter in Thyroid Cancers in an Iodine‐deficient Population: An Immunohistochemical Study
Authors: Mishra Anjali , Pal Lily , Mishra Saroj Kanta 
Published: July 2007

AbstractBackgroundThere are significant differences in the prevalence and behavior of differentiated thyroid cancers (DTC) in the iodine‐deficient areas (IDA) and iodine‐sufficient areas (ISA) of the world. The sodium iodide symporter (NIS), mediates active transport of iodide across the basolateral aspect of the thyroid follicular cell. However, no study had specifically addressed the issue of expression of sodium iodide symporter (NIS) in thyroid cancer specimens from IDA. The aim of the present study was to find an expression pattern of NIS in DTC in an iodine‐deficient population, and to correlate it with histological subtypes, i.e., papillary carcinoma (PTC), follicular carcinoma (FTC), poorly differentiated carcinoma (PDTC), as well as with clinicopathological risk factors and iodine (131I) uptake by distant metastases.MethodsImmunohistochemistry was carried out in 39 cases of thyroid cancer (41 samples) including PTC (15), FTC (10), PDTC (9), anaplastic cancer (5), and resected metastases (2). Expression was correlated with the patient’s age, sex, tumor size, presence or absence of extrathyroidal invasion, distant and lymph node metastases, and whole body radioiodine scan.ResultsOverall, 61.8% of DTC patients showed NIS expression. There was no significant difference in expression rate between PTC (73.3%) and FTC (70.0%). However, expression was significantly less in PDTC (33.3%). There was no correlation between NIS expression and any clinicopathological risk factor (p >. 05). The results of NIS expression were not concordant with 131I uptake by metastases in 4 of 10 cases. 131I uptake was absent in one case despite the finding that a metastatic site itself showed NIS expression in that case, whereas in the remaining 9 cases 131I uptake was present although three cases did not show NIS expression.ConclusionsIn our experience, overall expression of NIS was comparable to other studies from ISA. We conclude that expression may not accurately predict radioactive iodine (RAI) uptake by metastases.
Artificial nest predation rates vary among habitats in the Australian monsoon tropics
Authors: Noske Richard A. , Fischer Sarah , Brook Barry W. 
Published: July 2007

AbstractRates of nest predation have frequently been shown to differ between fragmented and unfragmented habitats, but have rarely been compared among natural habitats in the same geographic region. In this study, artificial nests of two types (open cup and domed) were placed in four habitats (mangroves, monsoon rainforests, eucalypt woodlands and paperbark swamps) over 12 months in three localities near Darwin in the Australian monsoon tropics to determine the effects of habitat, season and nest type on the rate of nest predation. A quail egg and a similarly coloured plasticine egg were placed in each nest. Habitat had a strong effect on nest predation rates, with nests in mangroves experiencing predation rates more than four times higher than those in eucalypt woodlands and paperbark swamps. Despite the strong rainfall seasonality of the region, there was no consistent seasonal variation in nest predation rates. Nest type also had little influence on predation rates, except in paperbark swamps where open cup nests suffered a higher predation rate than domed nests. The study indicates that generalised nest predation rates for tropical regions, even for small areas (e.g. <17 km radius), might overlook substantial variation between habitats. Such variation confounds purported differences in nest predation rates between tropical and temperate regions.
Short‐term changes in plans to drink and importance of positive and negative alcohol consequences
Authors: Patrick Megan E. , Maggs Jennifer L. 
Published: July 2007

AbstractExperienced consequences predicted short‐term changes in alcohol use plans and perceptions of the importance of alcohol‐related consequences. Participants were 176 traditionally aged first‐year university students who completed a 10‐week telephone diary study (total weeks=1735). In multi‐level models, men and students who experienced more positive and negative consequences on average planned to drink more and rated avoiding negative consequences as less important. Students who experienced more positive consequences rated them as more important (between‐person analyses). Following weeks of experiencing relatively more positive drinking consequences, students planned to drink more and rated experiencing positive consequences as more important for the subsequent week (within‐person analyses). Challenges for intervening in the ongoing formation of anticipatory cognitions regarding alcohol use are discussed.
Paleoecological analyses of lake sediments reveal prehistoric human impact on forests at anthony island UNESCO World Heritage Site, Queen Charlotte Islands (Haida Gwaii), Canada
Authors: Lacourse Terri , Mathewes Rolf W. , Hebda Richard J. 
Published: July 2007

AbstractPollen and plant macrofossil analyses of lake sediments from Anthony Island in the southern Queen Charlotte Islands (Haida Gwaii), British Columbia, reveal 1800 yr of relatively stable temperate rainforest vegetation. Cupressaceae (cedar) pollen percentages and accumulation rates decline about 1000 cal yr BP, coincident with occupation of the island by Haida peoples, who use Thuja plicata (western red cedar) almost exclusively for house construction, dugout canoes, monumental poles, and many other items. Anthropogenic disturbance offers the most likely explanation for the decline of T. plicata.
Streamline topology in the near wake of a circular cylinder at moderate Reynolds numbers
Authors: BRØNS MORTEN , JAKOBSEN BO , NISS KRISTINE , BISGAARD ANDERS V. , VOIGT LARS K. 
Published: July 2007

For the flow around a circular cylinder, the steady flow changes its topology at a Reynolds number around 6 where the flow separates and a symmetric double separation zone is created. At the bifurcation point, the flow topology is locally degenerate, and by a bifurcation analysis we find all possible streamline patterns which can occur as perturbations of this flow. We show that there is no a priori topological limitation from further assuming that the flow fulfils the steady Navier–Stokes equations or from assuming that a Hopf bifurcation occurs close to the degenerate flow.The steady flow around a circular cylinder experiences a Hopf bifurcation for a Reynolds number about 45–49. Assuming that this Reynolds number is so close to the value where the steady separation occurs that the flow here can be considered a perturbation of the degenerate flow, the topological bifurcation diagram will contain all possible instantaneous streamline patterns in the periodic regime right after the Hopf bifurcation. On the basis of the spatial and temporal symmetry associated with the circular cylinder and the structure of the topological bifurcation diagram, two periodic scenarios of instantaneous streamline patterns are conjectured. We confirm numerically the existence of these scenarios, and find that the first scenario exists only in a narrow range after the Hopf bifurcation whereas the second one persists through the entire range of Re where the flow can be considered two-dimensional. Our results corroborate previous experimental and computational results.