bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystallization Behavior of Poly(ε‐caprolactone) Grafted onto Cellulose Alkyl Esters: Effects of Copolymer Composition and Intercomponent Miscibility
Authors: Kusumi Ryosuke , Teramoto Yoshikuni , Nishio Yoshiyuki 
Published: September 2008

AbstractGraft copolymers of CA and CB with PCL were prepared at compositions rich in PCL. Kinetic DSC data were analyzed in terms of a folded‐chain crystallization formula expanded for a binary mixing system of amorphous/crystalline polymers. The order of crystallization rates was plain PCL > CA‐g‐PCL (DS = 2.98) > CB‐g‐PCL (DS = 2.1–2.95) > CA‐g‐PCL (DS = 2.1–2.5), and the fold‐surface free energy of the PCL crystals obeyed the reverse order. POM revealed a generally tardy growth of spherulites for all the graft copolymers. The slower crystallization process may be ascribed primarily to the compulsory effect of anchoring PCL chains onto the semi‐rigid cellulose backbone. Intercomponent miscibility of the CA/PCL and CB/PCL pairs was also taken into consideration.magnified image
Putting Electrospun Nanofibers to Work for Biomedical Research
Authors: Xie Jingwei , Li Xiaoran , Xia Younan 
Published: September 2008

AbstractElectrospinning has been exploited for almost one century to process polymers and related materials into nanofibers with controllable compositions, diameters, porosities, and porous structures for a variety of applications. Owing to its high porosity and large surface area, a non‐woven mat of electrospun nanofibers can serve as an ideal scaffold to mimic the extracellular matrix for cell attachment and nutrient transportation. The nanofiber itself can also be functionalized through encapsulation or attachment of bioactive species such as extracellular matrix proteins, enzymes, and growth factors. In addition, the nanofibers can be further assembled into a variety of arrays or architectures by manipulating their alignment, stacking, or folding. All these attributes make electrospinning a powerful tool for generating nanostructured materials for a range of biomedical applications that include controlled release, drug delivery, and tissue engineering.magnified image
Personality dimensions measured using the Temperament and Character Inventory (TCI) and NEO‐FFI on a Polish sample
Authors: Mikołajczyk Elżbieta , Ziȩtek Joanna , Samochowiec Agnieszka , Samochowiec Jerzy 
Published: September 2008

AbstractThe results of two self‐administered, paper‐and‐pencil tests based on biosocial theory of personality have been compared simultanously: the Temperament and Character Inventory (TCI) and NEO Five Factor Inventory (NEO‐FFI). The stability of the personality dimensions was assessed across age, sex and education level samples in a group of 406 Polish adults with major mental diseases excluded by use of PRIME‐MD questionnaire. Significant effects of age, sex, and education have been found while comparing personality dimensions in both temperamental (novelty seeking, NS; harm avoidance, HA; reward dependence, RD; persistence, P) and character scales (cooperativeness, C; self‐transcendence, ST) in TCI. Among subscales of temperament only NS1, RD4 were stable according to concerning factors. All converted to their age and sex norms NEO‐FFI dimensions were stable according to sex. Extraversion scale was changeable depending on age (p = 0.04). Neuroticism dimension was a little higher in lower educated group (p = 0.035).To sum up, it was concluded that sex‐ and age‐specific norms for the dimensions of the Polish version of TCI are necessary considering the established significant differences. Particular personality genetic studies should account for age, sex and also educational differences in their methods of associative studies.Conclusions: In the exploration of personality dimensions on healthy volunteers the Polish version of NEO‐FFI corresponds better than TCI to theory of stability and genetic determinants of human personality. As the study included persons with excluded major mental diseases, the sample is appropriate to provide a control group in the reaserch of psychiatric patients using both TCI and NEO‐FFI.Significant Outcomes: TCI scores for persons with excluded mental disease are highly changeable depending on age, sex and education. Adjusted to sex and age scores NEO‐FFI corresponded better than TCI to stability and genetic determinants of human personality. Copyright © 2008 John Wiley & Sons, Ltd.
Production of Long‐Chain Branched Polyolefins with Two Single‐Site Catalysts: Comparing CSTR and Semi‐Batch Performance
Authors: Mehdiabadi Saeid , Soares João B. P. , Dekmezian Armenag H. 
Published: September 2008

AbstractWe developed a mathematical model to describe the solution polymerization of olefins with two single‐site catalysts in a series of two CSTRs. The model was used to simulate processes where semi‐crystalline macromonomers produced in the first reactor are incorporated as long chain branches onto amorphous (or lower crystallinity) chains in the second reactor (cross‐products). The simulation results show that CSTRs are more efficient to make chains with high LCB density and high weight percent of cross‐products. The model can also predict the polydispersity index, average chain lengths, and fractions of the different polymer populations, and help the polymer reactor engineer formulate new products with complex microstructures.magnified image
Structural, spectroscopic, and theoretical studies of a very short OHO hydrogen bond in bis(4‐(N‐methylpiperidinium)‐butyrate) hydrobromide
Authors: Bartoszak‐Adamska Elżbieta , Dega‐Szafran Zofia , Jaskolski Mariusz , Szafran Mirosław 
Published: September 2008

AbstractThe molecular structure of bis(4‐(N‐methylpiperidinium)‐butyrate) hydrobromide, (MPBu)2HBr, has been characterized by single crystal X‐ray diffraction, infrared and NMR spectroscopies, and by DFT calculations. The crystals of the title compound at 140 K are monoclinic, space group C2/c, with a = 11.7118(4), b = 7.8737(2), c = 23.9240(8) Å3 , β = 90.431(3)°, V = 2206.1(1) Å3, and Z = 4. Two 4‐(N‐methylpiperidinium)‐butyrate moieties are joined by a very short and centrosymmetric O.H.O hydrogen bond of 2.436(2) Å3 . The piperidine ring adopts a chair conformation with the methyl group in the equatorial and the bulky (CH2)3COO substituent in the axial position. The broad absorption band below 1500 cm−1 in the FTIR spectrum confirms the existence of a very short O H O hydrogen bond. The 1H and 13C NMR spectra are interpreted on the basis of 2D experiments and the calculated GIAO/B3LYP/6‐31G(d,p) magnetic isotropic shielding tensors. In the optimized structure of the complex, a 4‐(N‐methylpiperidinium)‐butyrate zwitterion interacts with a 4‐(N‐methylpiperidinium)‐butyric acid cation forming an O .HO hydrogen bond of 2.580 Å3 . Copyright © 2008 John Wiley & Sons, Ltd.
Self‐assembly of N‐carboxyethylchitosan near the isoelectric point
Authors: Mincheva Rosica , Bougard François , Paneva Dilyana , Vachaudez Magali , Manolova Nevena , Dubois Philippe , Rashkov Iliya 
Published: September 2008

AbstractFor the first time the possibility to obtain nanostructures by self‐assembly of chitosan polyampholytic derivative was demonstrated. The self‐assembly of N‐carboxyethylchitosan (CECh) took place only near its isoelectric point (pH 5.0–5.6). Out of the pH range 5.0–5.6, CECh aqueous solutions behaved as real solutions. Dynamic light scattering and atomic force microscopy analyses revealed that spherically shaped or rod/worm‐like nanosized assemblies were formed depending on the polymer molar mass, pH value, and polymer concentration. CECh of two different molar masses was studied in concentrations ranging from 0.01 to 0.1 mg/mL. The structures from CECh of weight‐average molar mass (Mw) 4.5 × 103 g/mol were spherical regardless the pH and polymer concentration. In contrast, CECh of high molar mass (HMMCECh, Mw = 6.7 × 105 g/mol) formed self‐assemblies with spherical shape only at pH 5.0 and 5.6. At pH 5.2 spherical nanoparticles were obtained only at polymer concentration 0.01 mg/mL. The mean hydrodynamic diameter (Dh) of the obtained nanoparticles was in the range from 30 to 980 nm. On increasing the concentration, aggregation of the nanoparticles appeared, and at HMMCECh concentration 0.1 mg/mL, rod/worm‐like structures were obtained. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6712–6721, 2008
The reliability, responsiveness and clinical utility of the proximat: A new tool for measuring hip range of movement in children with cerebral palsy
Authors: Pott Patricia , Selley Andrea , Tyson Sarah F. 
Published: September 2008

AbstractBackground and Purpose. Monitoring range of movement is a key aspect of managing hip problems in children with cerebral palsy. The aim of this study was to assess the clinical utility, reliability and responsiveness of a new measurement tool, the Proximat, for hip range of movement. Method. Passive hip abduction, adduction, medial and lateral rotation were measured by using the Proximat on 26 children with cerebral palsy attending three special schools: 16 of whom are boys, mean age = 7 years and 6 months (standard deviation = 4.2 years), range 2–15 years. Testing was undertaken by two physiotherapists to assess interrater reliability and repeated the following day to assess test–retest reliability. Total, random and systematic errors were calculated for interrater and test–retest. Results. The Proximat was quick and easy to use and acceptable to the children. High reliability was found for all movements (intraclass correlation coefficient = 0.83–0.93) with reasonable responsiveness; total error was 2.5–12 degrees. Most of the error was random with little evidence of systematic bias. Conclusions. The Proximat is a reliable, responsive and acceptable method of measuring passive hip movements in children with cerebral palsy in day‐to‐day clinical practice. A change of 8–12 degrees is needed to overcome measurement error and to indicate that a ‘true’ change in range of movement has occurred. Copyright © 2008 John Wiley & Sons, Ltd.
Photoconductance‐calibrated photoluminescence lifetime imaging of crystalline silicon
Authors: Herlufsen Sandra , Schmidt Jan , Hinken David , Bothe Karsten , Brendel Rolf 
Published: September 2008

AbstractWe use photoluminescence (PL) measurements by a silicon charge‐coupled device camera to generate high‐resolution lifetime images of multicrystalline silicon wafers. Absolute values of the excess carrier density are determined by calibrating the PL image by means of contactless photoconductance measurements. The photoconductance setup is integrated in the camera‐based PL setup and therefore identical measurement conditions are realised. We demonstrate the validity of this method by comparison with microwave‐detected photoconductance decay measurements. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atmospheric radiation and atmospheric humidity
Authors: Harries J. E. 
Published: September 2008

AbstractThis paper presents a report of some aspects of the effect of the dominant greenhouse gas in the earth's atmosphere, water vapour, on the radiative balance of the planet. Results from two satellite experiments which provide data on the concentration of water vapour in the upper and middle troposphere are presented. the first is the HALogen Occultation Experiment, HALOE, on the National Aeronautics and Space Administration Upper Atmosphere Research Satellite, for which retrievals of humidity have been made down to levels of about 150 hPa. These data reveal a number of interesting features in terms of the space and time variability of water vapour in the lower stratospherehpper troposphere. Comparison of HALOE measurements with the water vapour fields calculated in one general circulation climate model reveal substantial differences, which could significantly affect calculations of radiative balance. A second source of global data is the Television Infra‐red Observation Satellite's Operational Vertical Sounder, TOVS, which uses infrared vertical soundings. Considerable variability of upper tropospheric humidity is revealed by TOVS measurements, and an interesting relationship between brightness temperature and relative humidity, identified by other workers, is discussed. Sensitivity studies are presented of the effect on the outgoing‐radiation spectrum of varying the amount of water vapour throughout the troposphere. It is shown that uncertainties of only a few percent in knowledge of the humidity distribution in the atmosphere could produce changes to the outgoing spectrum of similar magnitude to that caused by doubling carbon dioxide in the atmosphere. Errors in the water vapour amounts generated in model simulations of the climate could, therefore, be significant in climate change calculations.
A group‐sequential design for clinical trials with treatment selection
Authors: Stallard Nigel , Friede Tim 
Published: September 2008

AbstractA group‐sequential design for clinical trials that involve treatment selection was proposed by Stallard and Todd (Statist. Med.2003;22:689–703). In this design, the best among a number of experimental treatments is selected on the basis of data observed at the first of a series of interim analyses. This experimental treatment then continues together with the control treatment to be assessed in one or more further analyses. The method was extended by Kellyet al.(J. Biopharm. Statist.2005;15:641–658) to allow more than one experimental treatment to continue beyond the first interim analysis. This design controls the familywise type I error rate under the global null hypothesis, that is in the weak sense, but may not strongly control the error rate, particularly if the treatments selected are not the best‐performing ones. In some cases, for example when additional safety data are available, the restriction that the best‐performing treatments continue may be unreasonable. This paper describes an extension of the approach of Stallard and Todd that enables construction of a group‐sequential design for comparison of several experimental treatments with a control treatment. The new method controls the type I error rate in the strong sense if the number of treatments included at each stage is specified in advance, and is indicated by simulation studies to be conservative when the number of treatments is chosen based on the observed data in a practically relevant way. Copyright © 2008 John Wiley & Sons, Ltd.
Frailty modelling for clustered recurrent incidence of diarrhoea
Authors: Elgmati E. , Fiaccone R. , Henderson R. , Mohammadi M. 
Published: September 2008

AbstractRecurrent incidence of infant diarrhoea is studied, using daily data collected in Salvador, Brazil, from 754 children over 455 days. Aalen's additive intensity model is taken as the basis of the modelling strategy and a frailty extension is proposed. The idea is to estimate the frailty dynamically as time proceeds and information accrues. This provides an alternative to the inclusion of dynamic covariates based on individual event patterns. Simulation results indicate good performance of the estimation methods. In our first analysis, there is no account taken in the natural clustering of the children into 21 different districts of the city. The model is therefore extended to incorporate the possibility of spatial or spatio‐temporal clustering effects, possibly caused by unobserved environmental factors or infectivity. Significant frailty and significant clustering are both identified in the data. Copyright © 2008 John Wiley & Sons, Ltd.
Sweating the small stuff: how different types of hassles result in the experience of stress
Authors: McIntyre Kevin P. , Korn James H. , Matsuo Hisako 
Published: September 2008

AbstractThe current study examines the level of stress caused by different types of daily hassles. Using an open‐ended response format, participants (n = 164) described hassles that they were currently experiencing in their lives, and then rated their hassles on dimensions of perceived control, negative emotions, importance, as well as the overall amount of stress that they associated with each hassle. Reported hassles were coded into one of four types (interpersonal, intrapersonal, school/work, everyday living), and relationships between control, negative emotions and importance on stress by type of hassle were examined. Results indicate that for all types of hassles, the amount of negative emotions that a hassle evokes is the strongest predictor of stress. In addition, hassles' importance significantly predicts stress for intrapersonal hassles, school/work hassles and everyday living hassles. Perceived control, however, only predicts stress due to everyday living hassles. Gender differences in the experience of different types of hassles were also found, with female participants reporting a greater number of interpersonal hassles and associating interpersonal hassles with more negative emotions than males. This study extends the literature on hassles by describing the conditions under which different types of everyday events become stressful. Copyright © 2008 John Wiley & Sons, Ltd.
Analysis of oil content of maize by wide‐line NMR
Authors: Alexander D. E. , Silvela L. S. , Collins F. I. , Rodgers R. C. 
Published: September 2008

AbstractA series of experiments to define feasibility, accuracy, and precision of wide‐line nuclear magnetic resonance spectroscopy as a nondestructive analytical tool for the oil content of living seeds is described. Corn samples, ranging from single seeds to 25 g, were scanned by NMR and gravimetrically analyzed. A high positive correlation (r = 0.99+) was invariably encountered. Single, 30‐sec NMR scans on 25‐g corn samples gave estimates within ŷ33 ing of the “true” oil content 95% of the time. Error associated with single, 30‐sec scans of individual corn kernels amounted to ŷ1.3 mg of oil at the same confidence level. Samples containing more than 4.5% moisture contribute to the NMR signal, and therefore oil content is overestimated.A new dimension is added to the breeding and genetics of oil crops by the application of the NMR technique in that the process is non‐destructive and feasible even for single seeds. The usefulness of the technique in studies involving the nature of water and its surrounding medium is suggested.
Viscosity characteristics of aqueous solutions of block copolymers of propylene and ethylene oxides
Authors: Schmolka Irving R. , Bacon Leslie R. 
Published: September 2008

AbstractBrookfield viscosity measurements were made on aqueous solutions of surface‐active agents composed of block copolymers of propylene and ethylene oxides in which the molecular weights of the polymers varied from 1100 to over 15,000. The hydrophobia bases were polyoxypropylene glycols varying in molecular weight from 940 to 4000. To these were added varying amounts of ethylene oxide so that the polyoxyethylene hydrophil comprised from 15 to 80% of the surfactant total weight.This work has materially expanded previous viscosity studies of aqueous solutions of nonionic surfactants by using a unique type of hydrophobe, two ethylene oxide chains, and far higher molecular weights of hydrophobe and of hydrophil, up to 280 moles of ethylene oxide.The surface‐active agents with hydrophobe base molecular weights from 940 to 1100, and in which the polyoxyethylene sections comprised from 15 to 80% of the total weight, did not form gels in aqueous solution. Some surfactants with a hydrophobe base molecular weight of 1750 to 2750, to which varying amounts of polyoxyethylene were added, formed gels in water at a surfactant concentration range of 40% to 80%. With a hydrophobe molecular weight of 3250, gels formed at from 30% to 90% surfactant concentration, while with one nonionic derived from a 4000 molecular weight hydrophobe, a gel formed at only 20% polyol concentration.Two viscosity maxima were found in some cases, as reported occasionally for other systems. An increase in temperature from 0C to 50C generally reduced the viscosity of systems based on hydrophobes of 1175 and lower molecular weights, and increased it in systems based on hydrophobes of 1750 and higher molecular weights.The behavior of these surfactants in forminggels is explained on the basis of hydrogen bonding, micellar aggregation and water entrapment. The moles of water per ethylene oxide group in the adduct varied with the hydrophobe base weight and with the polyoxyethylene hydrophil, and within systems showing maximum viscosities, ranged from 0.3 to 17.1, at 25C, which is much higher than observed in other nonionics.
Sulfur dichlonde diadducts of unsaturated fatty derivatives. II reactions with nucleophiles
Authors: Grimm Robert A. 
Published: September 2008

AbstractThe chloro groups in the bis‐9(10)‐[alkyl‐10 (9)‐chlorooetadecanoate]‐sulfides described previously (9) underwent reaction with water, alcohols, ammonia, amines, cyanides, cyanates, thiocyanates, and azides. The rates of these reactions were such that the chloro groups were completely replaced before significant attack on the ester group occurred. Without exception, the products of these reactions were the open‐chain disubstituted‐sulfide diesters, e.g. bis‐9(10)‐[ethyl‐10 (9)‐aminooctadecanoate]‐sulfide, and no evidence was found for cyclic,e.g. thiomorpholine, structures. The sulfur dichloride diadducts fromcis‐2‐butene andtrans‐ 2‐ butene were also subjected to hydrolysis and ammonolysis and again, only the open‐chain sulfides, e.g. bis‐2‐[3‐amino‐butyl]‐sulfide, were formed. The diol‐sulfides from m‐olefins differed from the diol‐sulfides oftrans‐ olefins in both physical and special properties. A similar difference was noted in the diamino‐sulfides. Several of the fatty products were oxidized to the corresponding disubstituted sulfone diesters.
Recovery of volatile compounds from butter oil
Authors: Forss D. A. , Holloway Gwenda L. 
Published: September 2008

AbstractThree methods for the isolation of volatile compounds from oils and fats were compared using small concentrations (approximately 1 ppm) of added C3–12n‐alkan‐2‐ones and C2–10n‐alkan‐1‐ols in commercial butter oil. These were : high vacuum degassing, cold‐finger molecular distillation and reduced pressure steam distillation. Several modifications were incorporated. The highest yields of all compounds were obtained by cold‐finger molecular distillation but difficulties were encountered in subsequent analysis. It was more convenient to recover compounds boiling below 150C by either high vacuum degassing or reduced pressure steam distillation. The latter was more efficient for the higher boiling compounds. Extraction with organic solvents was not required in any of these techniques.The combination of high vacuum degassing and cold‐finger molecular distillation was found to be the best method of analyzing the complete range of model compounds.
Estimation of crude fiber in dehulled soybeans
Authors: Anderson R. E. , Holt K. E. 
Published: September 2008

AbstractThe determination of crude fiber in soybeans is a lengthy and time‐consuming procedure which requires extraction, digestion, and incineration and is not suitable as a routine processing‐control tool. A short control procedure has been developed, employing photomicroscopy, which is based on the characteristics of soybean hull cellulose to rotate plane‐polarized light. The sample is mounted on a microscope slide, treated with trichloro‐acetic acid, and placed in a polarizing projection microscope; the image is compared with a series of standard photomicrographs. The amount of hulls present in the sample is measured quantitatively, and an estimation is made on the crude fiber. The crude fiber estimation on de‐hulled soybeans can be made in 15 min compared with 8 to 12 hr by using the official crude fiber method.