bluuebunny/crossref_metadata_2025_split huggingface dataset:
Syntheses and properties of hyperbranched polybenzoxazole by thermal cyclodehydration of hyperbranched poly[o‐(t‐butoxycarbonyl)amide] via A2 + B3 approach
Authors: Kudo Hiroto , Maruyama Ken , Shindo Syoko , Nishikubo Tadatomi , Nishimura Isao 
Published: April 2006

AbstractThe syntheses and properties of hyperbranched poly(o‐hydroxyamide) [poly(HAB‐BCC)‐ABP], poly[o‐(t‐butoxycarbonyl)amide] [poly(HAB‐BCC)‐ABP‐t‐BOC], and polybenzoxazole [poly(HAB‐cycloBCC)] were examined. Poly(HAB‐BCC)‐ABP was obtained from the polycondensation reaction of 3,3‐dihydroxy‐4,4′‐diaminobiphenyl (HAB) as an A2‐monomer and 1,3,5‐benzenetricarboxylchloride (BCC) as a B3‐monomer with 2‐amino‐4‐t‐butylphenol (ABP) in NMP in the presence of pyridine for 24 h. The reaction of poly(HAB‐BCC)‐ABP and di‐t‐buthylcarbonate (DiBOC) was performed to obtain the corresponding poly(HAB‐BCC)‐ABP‐t‐BOC with pendant t‐BOC groups. The thermal cyclodehydration of poly(HAB‐BCC)‐ABP‐t‐BOC was carried out in the film sate at 400 °C, affording the poly(HAB‐cyclo‐BCC) in quantitative yield. Furthermore, the solubilities and thermal properties of these polymers were examined. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3640–3649, 2006
Resampling and deconvolution of linear time‐of‐flight records for enhanced protein profiling
Authors: Malyarenko Dariya I. , Cooke William E. , Tracy Eugene R. , Drake Richard R. , Shin Susanna , Semmes O. John , Sasinowski Maciek , Manos Dennis M. 
Published: April 2006

AbstractWe have developed a peak deconvolution strategy that is applicable to the full mass range of a time‐of‐flight (TOF) spectrum. This strategy involves resampling a spectrum to create a time series that has equal peak widths (in time) across the entire spectrum, and then using the deconvolution filters we have previously described. We use this technique to deconvolve the protein mass spectra for blood serum and cell lysates acquired on three separate TOF instruments. Following deconvolution, we resolve spectral structures consistent with expected events such as multiply charged ions, matrix adducts and post‐translational protein modifications. The deconvolution procedure produces a 40% improvement in the resolution and enhanced experimental sensitivity over the full length of the linear TOF record, up to m/z 150 000. This approach is particularly appropriate for automated data analysis and peak detection in dense TOF spectra. Copyright © 2006 John Wiley & Sons, Ltd.
Examination of the food processes on mixed inferior host plants in a polyphagous grasshopper
Authors: Miura Kazumi , Ohsaki Naota 
Published: April 2006

AbstractThe mass gain of polyphagous grasshoppers fed a mixture of intrinsically inferior plants is often greater than that of grasshoppers fed each inferior plant alone. We examined the cause of this greater mass gain by assessing the food processes of a polyphagous grasshopper in detail. Food processes were divided into five stages: consumption, fecal mass, assimilated food, approximate digestibility, and efficiency of conversion of digested food (ECD). Using final‐stadium female nymphs of the polyphagous grasshopper Parapodisma subastris, we compared the mass gain of nymphs fed the inferior plants Polygonum cuspidatum and Weigela hortensis or the superior plant Artemisia princeps. The mass gain of nymphs fed a single inferior plant was less than that of nymphs fed the superior plant because of reduced ECD. However, the mass gain of nymphs fed a mixture of the two inferior plants was not only greater than that of nymphs fed a single inferior plant, but also did not differ from that of nymphs fed the superior plant. Since consumption by nymphs fed the mixture was greater than that by nymphs fed P. cuspidatum and smaller than that by nymphs fed W. hortensis, and since the ECD of nymphs fed the mixture was greater than that of nymphs fed W. hortensis and was not different from that of nymphs fed P. cuspidatum, consumption and ECD appeared to cause the greater mass gain in nymphs fed the mixture.
Serum levels of angiogenic factors indicate a pro‐angiogenic state in adults with sickle cell disease
Authors: Duits Ashley J. , Rodriguez Tati , Schnog John‐John B. ,   the CURAMA Study Group
Published: April 2006

SummaryHypoxia‐induced angiogenesis may play an important role in the pathophysiology of sickle cell disease (SCD). Serum levels of angiopoietin (Ang)‐1, Ang‐2, vascular endothelial growth factor, placenta growth factor (PlGF), soluble tunica intima endothelial kinase 2 (sTIE2), erythropoietin (EPO) and endothelial activation markers (soluble vascular adhesion molecule‐1, soluble intercellular adhesion molecule‐1) were determined in controls, HbSS (n = 35) and HbSC (n = 23) patients. In the asymptomatic phase, serum Ang‐2 (P < 0·001), EPO (P < 0·001) and sTIE2 (P = 0·03) were elevated in patients. During painful crises, increased Ang‐2 (P < 0·001) and PlGF (P = 0·04) occurred in HbSS and Ang‐2 (P = 0·05) in HbSC patients. These results indicate a pro‐angiogenic state in SCD, mainly because of elevated Ang‐2 levels.
Comparison of two stainless steel files to shape simulated root canals
Authors: AL‐OMARI M.A.O. , BRYANT S. , DUMMER P.M.H. 
Published: April 2006

SummaryThe aim of this study was to compare the shaping ability of two stainless steel files using simulated canals. A total of 80 simulated canals of various angles and positions of curvature were prepared by hand using either Mani K‐Files or Micro Mega K‐Files. Following orifice enlargement each file type was used to prepare 40 canals employing a linear filing motion and an anticurvature stepback technique. Pre‐ and post‐operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount of material removed as a result of preparation were determined from composite images of superimposed pre‐ and post‐operative views. Overall, canal preparation with Mani K‐Files was significantly quicker (P7<0.0O5) and was associated with fewer instrument failures. Zips and elbows were observed in 70% of specimens with significantly more (P<0.05) occurring following preparation with Micro Mega K‐Files. Mani K‐Files created significantly more (P<0.01) danger zones. Micro Mega K‐Files created significantly wider (P<0.001) zips with significantly more (P<0.01) resin removed from the outer aspect of the curves and, thus, significantly more (P<0.01) transportation. Canal shape had a significant influence on preparation time (P<0.001), the incidence of zips (P<0.05) and danger zones (P<0.005), the width of zips (P<0.001) and transportation at the zips (P<0.001). Under the conditions of this study, Mani K‐Files were more effective than Micro Mega K‐Files and produced canals with better shapes. Original canal shape had a substantial influence on the outcome of shaping procedures.
LONG RUN DEMAND FOR LABOUR IN THE CONSUMER GOOD INDUSTRY
Authors: Steedman Ian 
Published: April 2006

ABSTRACTWe consider, for alternative models of production, the comparative statics of constant‐returns economies in long run competitive equilibrium, for which reswitching, capital‐reversing and consumption‐reversal are all completely absent. Notwithstanding the ‘well‐behaved’ nature of these economies, the use of labour per unit of output in the consumer good industry is always positively related to the real wage rate.
Low-Level Mesocyclonic Concentration by Nonaxisymmetric Transport. Part II: Vorticity Dynamics
Authors: Gaudet Brian J. , Cotton William R. , Montgomery Michael T. 
Published: April 2006

Abstract
An idealized supercell simulation using the Regional Atmospheric Modeling System (RAMS) produced an elongated low-level mesocyclone that subsequently collapsed into a concentrated vortex. Though vorticity continually increased in the mesocyclone due to horizontal convergence, the collapse phase was additionally characterized by rapidly decreasing pressure, closed streamlines, and the creation of a compact vorticity center isolated from the remaining vorticity. It was shown in Part I of this study that the concentration phase was not initiated by an increase in horizontal convergence, suggesting that the proximate cause resided elsewhere.
In this study, the vortex concentration in Part I is examined from a vorticity dynamics perspective. It is shown that concentration occurs when inward radial velocity and vertical vorticity become more spatially correlated in the region surrounding the nascent vortex. It is also emphasized that the anisotropy of the horizontal convergence, which is nearly plane-convergent and of comparable magnitude to the mesocyclonic vorticity, is critical to an understanding of the process. The resultant evolution is intermediate between a state of purely two-dimensional nondivergent dynamics and one in which plane convergence confines vorticity to its axis of dilatation. This intermediate state produces a concentrated vortex more rapidly than either end state. The unsteady nature of the initial vorticity band also serves to increase the circulation and wind speed amplification of the final vortex. It is shown how conceptual models in the fluid dynamics literature can be applied to predicting the time and length scales of tornadic mesocyclone evolution.
Arctic Ocean Ice Thickness: Modes of Variability and the Best Locations from Which to Monitor Them*
Authors: Lindsay R. W. , Zhang J. 
Published: April 2006

Abstract
Model simulations of Arctic sea ice and ocean systems are used to determine the major spatial and temporal modes of variability in the ice thickness. A coupled ice–ocean model is forced with daily NCEP–NCAR reanalysis surface air pressure and surface air temperature fields for the period 1951–2003 with the analysis of the results performed for the 51-yr period 1953–2003. Ice concentration data and ice velocity data (beginning in 1979) are assimilated to further constrain the simulations to match the observed conditions. The simulated ice thins over the study period with the area of greatest thinning in a band from the Laptev Sea across the Pole to Fram Strait. The thinning rate is greatest since 1988. The major spatial modes of variability were determined with empirical orthogonal functions (EOFs) for the ice thickness within the Arctic Ocean. The first three EOFs account for 30%, 18%, and 15%, respectively, of the annual mean ice thickness variance. The first EOF is a nearly basinwide pattern, and the next two are orthogonal lateral modes. Because of the nonstationary nature of the ice thickness time series, significant changes in the modes are found if a shorter period is analyzed. The second and third principal components are well correlated with the Arctic Oscillation. The model results are also used to simulate an observation system and to then determine optimal mooring locations to monitor the basinwide mean ice thickness as well as the spatial and temporal patterns represented in the EOF analysis. The nonstationary aspect of the ice thickness limits the strength of the conclusions that can be drawn.
Initially Forced Long Planetary Waves in the Presence of Nonzonal Mean Flow
Authors: Cerovečki Ivana , de Szoeke Roland A. 
Published: April 2006

Abstract
The purpose of this paper is to understand how long planetary waves evolve when propagating in a subtropical gyre. The steady flow of a wind-driven vertically sheared model subtropical gyre is perturbed by Ekman pumping that is localized within a region of finite lateral extent and oscillates periodically at about the annual frequency after sudden initiation. Both the background flow and the infinitesimal perturbations are solutions of a 2½-layer model. The region of forcing is located in the eastern part of the gyre where the steady flow is confined to the uppermost layer (shadow zone). The lateral scales of the forcing and of the response are supposed to be small enough with respect to the overall gyre scale that the background flow may be idealized as horizontally uniform, yet large enough (greater than the baroclinic Rossby radii) that the long-wave approximation may be made. The latter approximation limits the length of time over which the solutions remain valid. The solutions consist of (i) a forced response oscillating at the forcing frequency in which both stable (real) and zonally growing (complex) meridional wavenumbers are excited plus (ii) a localized transient structure that grows as it propagates away from the region of forcing. Application of the method of stationary phase provides analytical solutions that permit clear separation of the directly forced part of the solution and the transient as well as estimation of the temporal growth rate of the transient, which proves to be convectively unstable. The solutions presented here are relevant to understanding the instability of periodic (including annual period) perturbations of oceanic subtropical gyres on scales larger than the baroclinic Rossby radii of deformation.
Spatial Variations of Stirring in the Surface Ocean: A Case Study of the Tasman Sea
Authors: Waugh Darryn W. , Abraham Edward R. , Bowen Melissa M. 
Published: April 2006

Abstract
Stirring in the Tasman Sea is examined using surface geostrophic currents derived from satellite altimeter measurements. Calculations of the distribution of finite-time Lyapunov exponents (FTLEs) indicate that the stirring in this region is not uniform and stretching rates over 15 days vary from less than 0.02 day−1 to over 0.3 day−1. These variations occur at both small (∼10 km) and large (∼1000 km) scales and in both cases are linked to dynamical features of the flow. The small-scale variations are related to the characteristics of coherent vortex structures, and there are low FTLEs inside vortices and filaments of high FTLEs in strain-dominated regions surrounding these vortices. Regional variations in the stirring are closely related to variations in mesoscale activity and eddy kinetic energy (EKE). High values of mean FTLE occur in regions of high EKE (highest mean values of around 0.2 day−1 occur in the East Australia Current separation region) whereas small values occur in regions with low EKE (mean values around 0.03 day−1 in the east Tasman Sea). There is a compact relationship between the mean FTLEs and EKE, raising the possibility of using the easily calculated EKE to estimate the stirring. This possibility is even more intriguing because the FTLE distributions can be approximated, for the time scales considered here, by Weibull distributions with shape parameter equal to 1.6, which can be defined from the mean value alone.
Pd-catalysed Capping Removal on a Tri-differentiated α-Cyclodextrin
Authors: Bistri Olivia , Sinaÿ Pierre , Sollogoub Matthieu 
Published: April 2006

Abstract
A chemically novel palladium-catalysed sequential double de-O-allylation to produce a diol is presented and applied to the efficient removal of a cap on a polyfunctionalized cyclodextrin.
The Fluence Rate Determines the Synergistic Interaction of UV Radiation and Heat for Mitotic Recombination and Cell Inactivation in Yeasts
Authors: Kim Jin Kyu , Komarova Ludmila N. , Zhurakovskaya Galina P. , Petin Vladislav G. 
Published: April 2006

ABSTRACTThe significance of the UV fluence rate for the synergistic interaction of UV light (254 nm) and heat was demonstrated for the frequency of mitotic recombination in a wild‐type diploid yeast of Saccharomyces cerevisiae (strain T1) and for cell inactivation of two wild‐type diploid yeast of S. cerevisiae (strains T1, XS800). It was shown for mitotic recombination that a decrease in the intensity of UV exposure results in the necessity of decreasing the temperature at which UV irradiation occurs to provide the same value of the synergistic enhancement ratio. For cell inactivation, there was a specific temperature maximizing the synergistic effect for any constant fluence rate and the temperature range, synergistically increasing the inactivation effect of UV radiation, should be shifted to lower temperatures with a decrease in the fluence rate. To interpret the results observed, a simple mathematical model of the synergistic interaction was applied. The model suggests that the synergistic interaction of UV light and hyper‐thermia is expected to result from some additional effective damages arising from the interaction of some sublesions induced by both agents. On the basis of data obtained, it was supposed that the synergistic interaction of these factors might take place at small intensities of UV light and temperatures existing in the biosphere. In other words, for a long duration of interaction, which is important for problems of UV light protection and health effects, one can expect a synergistic interaction of this factor with environmental heat or physiological temperatures and thereby an increase in their inactivating and genetic consequences.
Some results on Markovian replacement processes
Authors: Mandl Petr 
Published: April 2006

SummaryA replacement of type (jk) in a Markov process with rewards means an instantaneous shift of the trajectory from state j into state k. A formula is obtained for the characteristic function of the total reward from the process under an arbitrary non-anticipative replacement policy. From the formula results are deduced concerning Markov policies, optimal policies and policies minimizing the variance of the reward.
Epidemics with carriers: The large population approximation
Authors: Pettigrew Hugh M. , Weiss George H. 
Published: April 2006

This paper applies the constant population approximation to the study of epidemics which involve more than a single type of infective. An example of this would be a situation in which both clinically infected individuals and subclinically infected individuals or carriers are present.We derive equations for the expected numbers of clinically infected individuals and carriers at any time t for the model with zero latent period and infectious periods having negative exponential distributions. From these equations we derive conditions under which a unimodal incidence curve can result, and expressions for the expected total epidemic size.
A diffusion approximation for correlation in queues
Authors: Woodside C. M. , Pagurek B. , Newell G. F. 
Published: April 2006

A diffusion model is used to find heavy traffic approximate autocorrelation functions for several variables in queueing systems (i.e. for waiting time, system time, number in system and unfinished work). A table is given by which correlations can easily be found for each variable in any GI/G/1 queue. Further, the infinite sum or integral of the autocorrelations is also found, and the spectral density function. The sum has applications in statistical analysis of queues.Extensive comparisons of approximate and exact correlations and their sums are reported, particularly for waiting times and system times, but also including number in system in M/M/1 queues. In general the correlations have similar accuracy to the probability distributions found by diffusion approximations. The percentage error is less for number in system than for waiting time.
Some new results on queueing networks with batch movement
Authors: Henderson W. , Taylor P. G. 
Published: April 2006

Product-form equilibrium distributions in networks of queues in which customers move singly have been known since 1957, when Jackson derived some surprising independence results. A product-form equilibrium distribution has also recently been shown to be valid for certain queueing networks with batch arrivals, batch services and even correlated routing.This paper derives the joint equilibrium distribution of states immediately before and after a batch of customers is released into the network. The results are valid for either discrete- or continuous-time queueing networks: previously obtained results can be seen as marginal distributions within a more general framework. A generalisation of the classical ‘arrival theorem' for continuous-time networks is given, which compares the equilibrium distribution as seen by arrivals to the time-averaged equilibrium distribution.
Overview of Safety Pharmacology
Authors: Porsolt Roger D. 
Published: April 2006

AbstractSafety pharmacology assesses the potential risks of novel pharmaceuticals for human use. ICH S7A guidelines recommend a core battery of studies on three vital systems: central nervous system (CNS), cardiovascular (CV) and respiratory. Primary CNS studies look for effects on general behavior, locomotion, neuromuscular coordination, the convulsive threshold, and vigilance. The primary CV test battery evaluates proarrhythmic risk using in vitro approaches (hERG channel and Purkinje fiber assays) and in vivo measurements in conscious animals via telemetry. Comprehensive cardiac risk assessment also includes full hemodynamic evaluation, most suitably conducted in the anesthetized large animal. Basic respiratory function can be approached via whole‐body plethysmography in conscious animals where sensitivity to respiratory‐depressant effects can be enhanced by exposure to increased CO2. Other aspects of safety pharmacology studies discussed are the timing of studies, ethical and animal welfare issues, and statistical evaluation.
An Overview of RNA Structure Prediction and Applications to RNA Gene Prediction and RNAi Design
Authors: Stormo Gary D. 
Published: April 2006

AbstractThis unit briefly describes the two fundamentally different methods for predicting RNA structures. The first is to find that structure with the minimum free energy of folding, as predicted by various thermodynamic parameters related to base‐pair stacking, loop lengths, and other features. If one has only a single sequence, this thermodynamic approach is the best available method. The second fundamental approach to RNA structure prediction is to use multiple, homologous sequences for which one can infer a common structure, and then try and predict a structure common to all of the sequences. Such an approach is referred to as a comparative method or phylogenetic method of RNA structure prediction.