bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of the Heterogeneous Association Constants of Metal Ions to ω‐Mercaptoalkanoic Acids by Using Double‐Layer Capacity Measurements
Authors: Burshtain Doron , Mandler Daniel 
Published: October 2004

AbstractThe binding of metal ions to ligands in homogeneous solutions and that to the same ligands anchored to metallic surfaces through self‐assembled monolayers (SAMs) are expected to differ primarily due to the difference in the degree of freedom of the ligands and the surface potential. We studied the heterogeneous binding of CdII ions to ω‐mercaptoalkanoic‐acid SAMs on Au. This was accomplished by adding metal ions at a constant pH and following the changes in the double‐layer capacity. A mathematical treatment, which is based on calculating the electrochemical‐potential differences at the double layer–solution interface, has been developed. Our approach follows that proposed by White et al.1, 2 and Kakiuchi,3 who used the acid–base equilibrium at the monolayer–electrolyte interface as a means of calculating the pK of ionizable SAMs. Experimentally, SAMs of ω‐mercaptoalkanoic acids, HS(CH2)nCO2H, with different chain lengths (i.e., n=2, 5, and 10) in 0.1 M sodium perchlorate were assembled on Au surfaces and studied. The capacity was measured first in the absence of CdII at different pH values, and then at a constant pH while increasing the concentration of CdII in the solution. We found that the interfacial capacity decreased as the concentration (of either protons or CdII) increased. The results matched the model fairly well, which allowed the extraction of the thermodynamic equilibrium constant that is established at the monolayer–electrolyte interface. The suggested mathematical treatment of this model system is simple and yet very useful for estimating the heterogeneous association constants of metal ions by SAMs.
Gaseous Ion Activation Dynamics: The Role of the Bulk Gas in the Racemization of Chiral Oxonium Ions
Authors: Filippi Antonello , Speranza Maurizio 
Published: October 2004

AbstractThe kinetics of the inversion of configuration of a family of chiral oxonium ions, that is, O‐protonated 1‐aryl‐1‐methoxyethanes [YMe+], were investigated in two different gaseous media (in CH3X with X=F and X=Cl) at 720 torr of pressure and in the temperature range: 25–140 °C. The activation parameters of the [YMe+] inversion reaction were found to obey two different isokinetic relationships (IKR), depending on the nature and the position of the substituents in the oxonium ions and on the nature of the bulk gas employed. The observation of two IKR for the same family of reactions was related to a switchover in the resonant vibrational energy exchange between the reactants' critical mode, active in the transition state (ω), and the discrete vibrational levels ν of the bulk gas. In CH3F, this vibrational–vibrational coupling switchover concerns the out‐of‐plane CF⋅⋅⋅HO bending (the Φ family) and the H3CF stretching (the Γ family) modes in the proton‐bound [CH3F⋅YMe+] complex. In CH3Cl, the coupling switchover concerns the out‐of‐plane CCl⋅⋅⋅HO bending (the Φ family) and the H3CCl methyl group rocking (the Γ family) modes in the proton‐bound [CH3Cl⋅YMe+] complex. The [YMe+] activation dynamics also determine the inversion dynamics. The [YMe+]ret⇄[YMe+]inv isomerization for the Φ family involves the same “thermodynamically most favorable” transition state in both the CH3F and the CH3Cl media, whereas the same process for the Γ family proceeds through different, dynamically favored transition states.
Zinc oxide – analogue of GaN with new perspective possibilities
Authors: Karpina V. A. , Lazorenko V. I. , Lashkarev C. V. , Dobrowolski V. D. , Kopylova L. I. , Baturin V. A. , Pustovoytov S. A. , Karpenko A. Ju. , Eremin S. A. , Lytvyn P. M. , Ovsyannikov V. P. , Mazurenko E. A. 
Published: October 2004

AbstractZinc oxide due to specific electrical, optical and acoustic properties is the important semiconductor material, which has many various applications. There is growing interest in ZnO due to its potential applicability for optoelectronic devices such as light‐emitting diodes, laser diodes and detectors for UV wavelength range. ZnO properties are very close to those of widely recognized semiconductor GaN. The band gap of ZnO (3.37 eV) is close to that of GaN (3.39 eV) but ZnO exciton binding energy (60 meV) is twice larger than that of GaN (28 meV). Optically pumped UV lasing have been demonstrated at room temperature using high textured ZnO films. The excitonic gain close to 300 cm–1 was achieved. ZnO thin films are expected to have higher quantum efficiency in UV semiconductor laser than GaN. The physical properties of ZnO are considered. PEMOCVD technology was used to deposit piezoelectric and highly transparent electroconductive ZnO films. Their properties are discussed. The experiments on polycrystalline ZnO films deposited by RF magnetron sputtering at different partial pressure of oxygen are presented. AFM images were studied in tapping mode for deposited films. The investigated films were dielectric ones and had optical transparency within 65‐85% at thickness in the interval 0.2‐0.6 μm. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Lattice dynamics and related properties of AIBIII and AIIBIV compounds, I. Elastic constants
Authors: Neumann H. 
Published: October 2004

AbstractThe present state of knowledge of the elastic properties of the ternary chalcopyrite compounds and some related materials is reviewed. Results of experimental elastic constant determinations are critically evaluated by comparing with other experimentally available material parameters that directly depend on the elastic constants. Possible reasons for existing discrepancies and obvious inconsistencies in the experimental data are discussed. The results of theoretical calculations of the elastic constants of these compounds based on different theoretical models and approaches are compared with experimental data and are assessed concerning achievable accuracy and reliability. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystallographic nets and their quotient graphs
Authors: Klee W. E. 
Published: October 2004

AbstractCrystallographic nets are defined. It is shown how these nets can be generated from finite graphs which are called the quotient graphs of the nets. The procedure yields the topology of the nets, their crystallographic point groups and their lattice types. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Diffusion induced segregation in the case of the ternary system sphalerite, chalcopyrite and cubanite
Authors: Blesgen T. , Luckhaus S. , Bente K. 
Published: October 2004

AbstractA mathematical model for describing natural and experimental diffusion induced segregation (DIS) in the case of a (Zn,Fe)S single crystal with three coexisting phases is derived. As main result, a new and quite general segregation principle for ternary systems is discovered where one phase has a flat free energy density and serves as catalyst for the segregation of the other two phases. The model includes also a stochastic noise term to represent fluctuations of the copper concentration. Numerical simulations in 2‐d underline the physical significance of the model and allow to make quantitative predictions. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth kinetics of ammonium oxalate monohydrate single crystals from aqueous solutions containing Co(II) and Ni(II) impurities
Authors: Mielniczek‐Brzóska E. , Sangwal K. 
Published: October 2004

AbstractThe growth kinetics of different faces of ammonium oxalate monohydrate (AO) single crystals from aqueous solutions containing different concentrations of Co(II) and Ni(II) ions at a constant temperature are described and discussed. It was found that: (1) at a given supersaturation σ, both Co(II) and Ni(II) ions lead to a decrease in the growth rates R of different faces of AO crystals, (2) the growth of a particular face of the crystals occurs above a critical supersaturation σd, but there is also another supersaturation barrier σ* when the rate abruptly increases with σ, and (3) the values of σd and σ* increase with increasing concentration ci of the impurity. The experimental R(σ) data for different concentrations ci of the impurities were analysed according to the model involving complex source of cooperating screw dislocations and concepts of instantaneous and time‐dependent impurity adsorption. Analysis of the data showed that: (1) adsorption of Co(II) and Ni(II) impurities occurs on the surface terrace of AO crystals, (2) there is a simple relationship between Langmuir constant K and the impurity concentration ci* corresponding to maximum surface coverage, and (3) the ratio σd/σ* of the supersaturation barriers observed in the presence of both impurities increases with an increase in impurity concentration ci, and may be explained from the standpoint of the mechanism of adsorption of impurity particles at kinks and ledges. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synergy of organic dyes for KDP crystal growth
Authors: Maeda Kouji , Sonoda Akira , Miki Hideo , Asakuma Yusuke , Fukui Keisuke 
Published: October 2004

AbstractSingle potassium dihydrogen phosphate (KDP) crystals were grown in a supersaturated solution containing an organic dye (sunset yellow FCF, brilliant blue FCF, and sky blue). The growth rate, morphology, and impurity dye distribution of faces, (100) and (101) in a KDP crystal were measured as dye concentration and the supersatutation of KDP were changed. Complete expressions for the effect of dye on all aspects of the growth of KDP crystals were discussed. The growth rates of (100) and (101) faces were well correlated by the empirical equation, and resulted in good estimation of the morphology. The distribution of dye in a KDP crystal was represented by the distribution model containing the minimum growth rate for coloring. The growth rate equation and distribution equation were expressed by functions of the supersaturation and dye concentration, and they could effectively provide the operational conditions with coloring the KDP crystal. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal growth of a new pseudopolymorph modification of the polymer compound [CuC12H8N4O2]n
Authors: Prokofiev A. V. , Dahlmann E. , Ritter F. , Assmus W. , Margraf G. , Wagner M. 
Published: October 2004

AbstractThe growth of crystals of the coordination polymer [CuC12H8N4O2]n with one‐dimensional magnetic properties is reported. Several approaches have been proposed and tested in order to diminish the growth anisotropy and plate‐like crystals of an area measuring up to 250×100 μm2 were grown. The structure and the composition of the crystals are slightly modified with respect to that of earlier synthesized powder. Instead of the water free triclinic phase a monoclinic phase, intercalated by water molecules, forms. In the new modification, the polymer chain layers are bound together by a network of hydrogen bonds, which are stronger than the usual Van der Waals interactions in the triclinic phase. The crystal morphology is plate‐like instead of the earlier obtained spherulitic needles. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of beryllium selenates by X‐ray powder diffraction, DTA and DSC
Authors: Koleva V. G. , Karadjova V. A. , Georgiev M. P. 
Published: October 2004

AbstractBeSeO4.2H2O and BeSeO4 have been studied röntgenographically: BeSeO4.2H2O forms orthorhombic crystals with lattice constants: a = 5.843(2) Å; b = 9.790(3) Å; c = 4.692(1) Å; V = 268.4(1) Å3. The crystals of BeSeO4 are tetragonal: a = 4.648(1) Å; c = 7.084 (3) Å; V = 153.1(1) Å3, SG I$ \bar 4 $. The thermal dehydration of BeSeO4.4H2O has been studied by TG, DTA and DSC methods. The dehydration occurs in four steps and intermediate hydrates BeSeO4.2H2O, BeSeO4.H2O and BeSeO4.0.5H2O are formed. The enthalpies of dehydration of the observed dehydration processes have been determined. The higher value of ΔHdeh of BeSeO4.4H2O as compared to those of other metal selenate tetrahydrates is discussed in terms of the strong Be–H2O interaction. The enthalpies of formation of BeSeO4.4H2O and BeSeO4.2H2O have been calculated. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Flow cytometry: Interesting tool for studying binding behavior of DNA on inorganic layered double hydroxide (LDH)
Authors: Burzlaff Arne , Brethauer Simone , Kasper Cornelia , Jackisch Björn‐Oliver , Scheper Thomas 
Published: October 2004

AbstractBackgroundA new method was established to characterize the binding kinetics of DNA toward layered double hydroxides (LDHs). The setup consisted of a newly developed sampling tube that allows the injection of analyte during the flow cytometric measurement.MethodsLayered double hydroxides consist of cationic metal hydroxide layers and exchangeable interlayer anions. This negatively charged structure permits biomolecules such as DNA to adsorb, and a so‐called DNA–LDH hybrid is formed. The hydroxide layers can be removed in acidic media and the DNA will be released. CERATOFIX® (a registered trademark of Süd‐Chemie AG NA that belongs to the family of LDHs, produced by Süd‐Chemie AG). The chemical structure can be summarized as [Mg2Al(OH)6](CO3)0.5. The binding capacity and kinetic characteristics of different types of CERATOFIX®NA for a model DNA was determined by flow cytometry.ResultsThe static binding capacities of the different LDHs were determined after 1‐ and 16‐h incubation with DNA solution, showing different binding patterns between the LDH materials. The binding kinetics were revealed by flow cytometric measurements in short‐term and long‐term kinetic experiments, showing that the majority of DNA adsorbs within the first 60 s.ConclusionsDNA removal from cell culture supernatants is one of the major concerns in downstream processing. Due to the anion exchange capabilities of LDHs it seemed a very interesting approach to use these materials for binding of DNA for elimination purposes. © 2004 Wiley‐Liss, Inc.
Cell cycle distribution of CD4+ lymphocytes in HIV‐1–infected subjects
Authors: Chaves Mariana Melillo Sauer , Kallas Esper Georges 
Published: October 2004

AbstractBackgroundApoptosis is one of the possible explanations for the progressive loss of CD4+ T lymphocytes in infection with the human immunodeficiency virus (HIV), which may interfere with cell cycle distribution. This study evaluated the cell cycle of CD4+ and CD8+ lymphocytes in HIV‐infected subjects and controls.MethodsTwo methods to identify lymphocytes for cell cycle analysis were evaluated, magnetic beads and concurrent staining, and both were followed by propidium iodide DNA labeling. The chosen method was used to evaluate the cell cycle of lymphocytes in HIV‐1–infected subjects and controls.ResultsThere was no significant difference between the two methods, although a higher variability was observed with the magnetic bead cell separation method. A higher proportion of cells in the S phase was observed in HIV‐1 patients (2.69% vs. 1.19%, P = 0.016), coupled with a decrease in G1 (96.11% vs. 98.10%, P = 0.005) in CD4+ lymphocytes, a phenomenon not observed in CD8+ lymphocytes. No correlation was detected between the different cell cycle phases and T‐lymphocyte counts or viral load.ConclusionsThe present work developed a new approach to evaluate lymphocyte cell cycle distribution, applied in the setting of HIV‐1 infection. It may contribute to the understanding of the CD4+ T‐lymphocytes depletion seen in these patients. © 2004 Wiley‐Liss, Inc.
Eating behavior disorders in Chilean infants
Authors: Sánchez Susana , Castillo‐Durán Carlos 
Published: October 2004

AbstractEating behavior disorders (EBD) are often observed in children. Most of the related research, however, has been performed in developed countries. In countries like Chile, characterization of food disorders during the first years of life is unknown.ObjectiveThe goal of the current study is to characterize the EBD of Chilean children during the first 2 years of life.MethodsWe studied 67 children (mean age = 5.4 months; range = 4–24 months). The study group (SG; according to criteria in the 4th ed. of the Diagnostic and Statistical Manual of Mental Disorders) consisted of 34 children with EBD whose mothers spontaneously consulted for difficulties for feeding and the control group (CG) included 33 healthy children. A structured recall was applied to their mothers.ResultsEBD onset was observed more frequently during the first semester of life and was associated with new foods. The children in the SG presented with lower birth weight (SG: 3,000 ± 500 g; CG: 3,400 ± 500 g; p < .001), weight/length (−0.4 ± 1.0 vs. 0.8 ± 1.1; p = .0001), and length/age z scores (−0.7 ± 1.0 vs. −0.1 ± 0.8; p = .007) than children in the CG. Early weaning before 4 months of age was more frequently found in the SG (44.1% vs. 12.1%; p = .04). The logistic regression showed as variables those associated with EBD, that is, birth weight and maternal history of EDB during her infancy (χ2, p = .0003). Mothers of children in the SG felt that their maternal role was more difficul and less satisfactory than mothers of children in the CG (χ2, p = .03).DiscussionEBDs in Chilean infants are observed during the first months of life and are associated with a lower birth weight, shortened exclusive breast‐feeding, maternal history of EBD during their infancy, and lower physical growth. Mothers of children with EBD frequently feel that their maternal role is difficult and unsatisfactory. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 348–355, 2004.
No longer just a pretty face: Fashion magazines' depictions of ideal female beauty from 1959 to 1999
Authors: Sypeck Mia Foley , Gray James J. , Ahrens Anthony H. 
Published: October 2004

AbstractObjectiveThe print media's depiction of the ideal of feminine beauty as presented to American women was examined for the years 1959–1999.MethodTrends were investigated through an analysis of cover models appearing on the four most popular American fashion magazines.ResultsBody size for fashion models decreased significantly during the 1980s and 1990s. There was also a dramatic increase in the frequency with which the media depicted the entire bodies of the models from the 1960s to the 1990s.DiscussionBoth the increasingly thin images and the striking increase in full‐body portrayals suggest an increase in the value placed by American society on a thin ideal for women, a change that is concurrent with the increase in disturbed eating patterns among American women. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 342–347, 2004.
Time course of symptom remission in eating disorders
Authors: Clausen Loa 
Published: October 2004

AbstractObjectiveThe study was carried out to test whether time to remission varies for different eating disorder symptoms.MethodSixty‐five patients (35 anorexic patients and 30 bulimic patients) treated with psychotherapy were interviewed 2½ years after initial assessment.ResultsThe anorexic physical symptoms remitted before the psychological symptoms of anorexia and bulimia nervosa, as did the bulimic behaviors: binging and purging. Nonpurging compensatory behavior and obsession with weight and shape were the last symptoms to remit. Differences between the anorexic and bulimic groups were found between the remission order of psychological symptoms.DiscussionIn spite of different treatments and symptoms between patients, the results support the notion of a common pattern in the process of change including a long and stepwise course. The results detail a template of the course to recovery for eating disorders. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 296–306, 2004.
Stress and hunger alter the anorectic efficacy of fluoxetine in binge‐eating rats with a history of caloric restriction
Authors: Placidi Rachel J. , Chandler Paula C. , Oswald Kimberly D. , Maldonado Christine , Wauford Pamela K. , Boggiano Mary M. 
Published: October 2004

AbstractObjectiveWe examined the effect of fluoxetine to suppress binge eating in rats with a history of caloric restriction (CR) and the extent to which this effect was altered by stress and hunger.MethodTo detect heightened sensitivity to fluoxetine, young female rats were used to determine a subthreshold anorectic dose (2 mg/kg, intraperitonally). Another group of rats was either fed ad libitum or given multiple CR (to 90% body weight) and refeeding‐to‐satiety cycles. One half of the rats were then either spared or subjected to foot shock stress before fluoxetine treatment.ResultsA history of CR alone produced bingelike eating on palatable food (p < .001) and, although stress did not affect intake, it rendered CR rats hypersensitive to the satiety effect of fluoxetine. The feeding‐suppression was mainly for chow (p < .05) and the effect was abolished if the rats were in negative energy balance.DiscussionResults support the utility of this animal model to elucidate serotonergic changes linking dieting to binge eating. The diverse effects of fluoxetine on the type of food, and in hungry versus sated rats, suggest alternate brain mechanisms should be concomitantly targeted for improved treatment of binge eating disorders. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 328–341, 2004.
Genetic and environmental influences on binge eating in the absence of compensatory behaviors: A population‐based twin study
Authors: Reichborn‐Kjennerud Ted , Bulik Cynthia M. , Tambs Kristian , Harris Jennifer R. 
Published: October 2004

AbstractObjectiveThe current study explores the extent to which genetic and environmental factors influence liability to binge eating in the absence of compensatory behaviors (BE) in a population‐based sample of twins.MethodQuestionnaire data on 8,045 same‐sex and opposite‐sex twins, aged 18–31 years, from a Norwegian twin registry were used to assess BE during the last 6 months.ResultsThe best‐fitting biometrical model suggested that the heritability of BE was 41% (95% confidence interval [CI]: 0.31–0.50). Individual environmental factors accounted for the rest of the variance (59%; 95% CI: 0.50–0.69). No significant sex differences were found, but the statistical power to detect such effects was low. Shared environmental influences on the liability to BE in males could not be ruled out.DiscussionThe findings indicate significant additive genetic influences on BE, supporting the validity of the core features of binge eating disorder as a diagnostic category. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 307–314, 2004.
Screening for eating disorders and high‐risk behavior: Caution
Authors: Jacobi Corinna , Abascal Liana , Taylor C. Barr 
Published: October 2004

AbstractObjectiveThe current study reviews the state of eating disorder screens.MethodsScreens were classified by their purported screening function: identification of cases with (a) anorexia nervosa only; (b) bulimia nervosa only; (c) eating disorders in general; (d) partial syndrome, eating disorder not otherwise specified (EDNOS), or subclinical; (e) not a–d but at high risk. Information is presented on development, psychometric properties, and external validation (e.g., sensitivity, specificity, positive predictive values, and negative predictive values).ResultsScreens differ widely with regard to objective, psychometric properties and the validation methodology used. Most screens that identify cases are not appropriate for the identification of at‐risk behaviors. Little data on the external validity of screens are available.DiscussionScreens should be used with caution. A sequential procedure, in which subjects identified as being at risk during the first stage is followed by more specific diagnostic tests during the second stage, might overcome some of the limitations of the one‐stage screening approach. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 280–295, 2004.