bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protein Chemistry on the Surface of Living Cells
Authors: Johnsson Nils , George Nathalie , Johnsson Kai 
Published: November 2004

AbstractThe interplay between carbohydrates, lipids, and proteins determines the stability and flexibility as well as the adhesive and responsive features of the surfaces of all cells. The molecular understanding of the interactions among and between the different classes of these biomolecules is rudimentary at best, a lack of suitable experimental methods being the major reason. Here we discuss a new approach for the specific labeling of fusion proteins of carrier proteins with synthetic compounds on cell surfaces and describe how this approach can be used to investigate the properties of the labeled molecules.
Sub‐and Supercritical CO2‐Extraction of Hypericum perforatum L.
Authors: Smelcerovic A. , Lepojevic Z. , Djordjevic S. 
Published: November 2004

AbstractThe extraction of Hypericum perforatum L. by liquid carbon dioxide (p = 80 bar, t = 15 °C) gave almost the same extract yield (1 %, w/w) as by supercritical (p = 100 bar, t = 40 °C) carbon dioxide, containing the same percentages of essential oil (about 6.4 %, w/w). The increase of the extract yield at higher pressure (250 to 350 bar) is due to the increase of extragent density, i.e., solubility. By increasing the grinding degree of the drug, a higher extract yield is obtained in the supercritical range under high pressure. GC‐MS analysis of the extract composition showed that the non‐terpene compounds have the highest contribution. The oil content in the drug, determined by steam distillation, was 0.058 %, w/w. The oil content in the extracts, calculated for the drug, was significantly higher (1.2 to 1.9 times).
Kinetic Reaction Models for the Selective Reduction of NO by Methane over Multifunctional Zeolite‐based Redox Catalysts
Authors: Sowade T. , Schütze F.‐W. , Berndt H. , Grünert W. 
Published: November 2004

AbstractKinetic measurements of the selective catalytic reduction (SCR) of NO by methane were performed over CeO2/H‐ZSM‐5, In‐ZSM‐5, and CeO2/In‐ZSM‐5 catalysts. The parameter space covered NO, CH4, and O2 concentrations varying from 250 to 1000 ppm, from 500 to 2000 ppm, and from 0.5 to 10 vol.‐%, respectively, space velocities between 5000 and 90000 h–1 and temperatures between 573 and 873 K depending on the catalyst activities. With CeO2/In‐ZSM‐5 an additional series of measurements was performed with moistened feed gas (0.5–10 vol.‐% H2O). On the basis of a pseudo‐homogeneous, one‐dimensional fixed‐bed reactor model, the data were fitted to a kinetic model that includes power rate laws for the reduction of NO and for the unselective total oxidation of methane. From analyses of isothermal data sets, almost all reaction orders were found to vary significantly with changing temperature, which indicates that the simple kinetic model cannot reflect the complex reaction mechanism correctly. Nevertheless, the data measured with In‐ZSM‐5 could be modeled with good accuracy over a wide range of reaction temperatures (150 K) while the accuracy was less satisfactory with the remaining data sets, in particular for data with the moist feed over CeO2/In‐ZSM‐5. With the latter catalyst it was not possible to represent the data measured in dry and in moist feed in a single model even upon confinement to fixed reaction temperatures. A comparison of the separate models established showed strong changes in the reaction orders in the presence of water, which occur apparently already at a very low water content (≤ 0.5 vol.‐%). The kinetic parameters found are in agreement with earlier conclusions about the reaction mechanisms. With In‐ZSM‐5, both reaction orders and the activation energy show a rate‐limiting influence of NO oxidation on the NO reduction path which is removed by the presence of the CeO2 promoter. A difference in the reaction mechanism over CeO2/In‐ZSM‐5 and CeO2/H‐ZSM‐5 is reflected in different kinetic parameters. The differences of the kinetic parameters between dry‐feed and moist‐feed models for CeO2/In‐ZSM‐5 reflect adsorption competition between the reactants and water.
CFD Modeling of Bubble Column Reactor Including the Influence of Gas Contraction
Authors: van Baten J.M. , Krishna R. 
Published: November 2004

AbstractIn this paper a CFD model for a bubble column reactor undergoing a first order reaction A → B is developed. The reactor operates in the homogeneous bubbly regime and has a diameter DT = 1 m and height HT = 5 m. The incoming gas stream contains inerts, varying in proportion from 10 % to 90 %. Three‐dimensional transient Eulerian simulations were carried out for an inlet superficial gas velocity UG = 0.04 m/s. Due to the consumption of A, the gas phase suffers contraction along the height of the reactor and as a consequence there is a significant change in the gas velocity along the column height; this variation in gas velocity is stronger when the incoming gas contains a smaller proportion of inerts. The CFD simulations show that there is a considerable influence of gas contraction on both the bubble column hydrodynamics and on the reactor conversion. None of the conventionally used reactor models is capable of describing the reactor performance in the case of high gas phase contraction.
The development of the P‐CAN, a measure to operationalize the pros and cons of anorexia nervosa
Authors: Serpell Lucy , Teasdale John D. , Troop Nicholas A. , Treasure Janet 
Published: November 2004

AbstractObjectiveResearch has suggested that a fundamental aspect of anorexia nervosa (AN) is its egosyntonic nature, the fact that it is often valued by individuals with the disorder. The current study describes the development of the P‐CAN, a quantitative measure of both positive (valued) and negative aspects of AN.MethodItems were derived from a previous qualitative study (Serpell, Treasure, Teasdale, & Sullivan. 1999. International Journal of Eating Disorders, 25, 177–186). Data from 233 women with AN were subjected to a principal components analysis.ResultsTen subscales were identified, six describing the pros of AN and four describing the cons of the illness.DiscussionThe P‐CAN shows good psychometric properties and should prove a useful tool for the measurement of attitudes towards AN, as well as offer insights into the maintenance of the disorder. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 416–433, 2004.
Group cognitive‐behavior therapy for bulimia nervosa: Statistical versus clinical significance of changes in symptoms across treatment
Authors: Openshaw Christine , Waller Glenn , Sperlinger David 
Published: November 2004

AbstractBackgroundCognitive‐behavior therapy (CBT) is the most effective treatment to date for bulimia nervosa. The current study investigated the effects of group CBT treatment (including some interpersonal elements) for bulimic clients.MethodTwenty‐nine patients completed the Stirling Eating Disorder Scales, the Beck Depression Inventory, and the Beck Anxiety Inventory at assessment, pretreatment, end of treatment, and at 6 months follow‐up. Symptom change was explored in two ways. Statistically significant change was determined using repeated‐measures analyses of variance and clinically significant change was determined using criteria proposed by Jacobson & Truax (1991, Journal of Consulting and Clinical Psychology, 59, 12–19).ResultsThere was an overall improvement in dimensional measures of bulimic and restrictive attitudes and behaviors (maintained at the 6‐month follow‐up), which was most closely matched by clinically significant changes in bulimic behaviors. Depression (but not anxiety) was also targeted effectively. Statistically significant improvements in psychological functioning were evident only for assertiveness, but the analysis of clinical significance showed improvement for some participants in self‐evaluation (self‐directed hostility).DiscussionGroup CBT (including interpersonal elements) is broadly effective when treating bulimia nervosa, but it does not work in all cases (and may lead to enhancement of restrictive characteristics in some cases). Tests of statistical and clinical significance provide different information, which can inform practice and aid in the development of treatments for patients who respond less well to current best practice. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 363–375, 2004.
Purging behaviors and comorbidity as predictive factors of quality of life in anorexia nervosa
Authors: González‐Pinto Ana , Inmaculada Failde , Cristina Rodriguez , de Corres Blanca Fernández , Sonsoles Enjuto , Fernando Ramírez , Purificacion López 
Published: November 2004

AbstractObjectiveThis study examined the predictive factors for the physical and mental summary components (PCS and MCS) of quality of life (SF‐36) in patients with anorexia nervosa.MethodForty‐seven patients with anorexia nervosa were studied. Assessment comprised psychiatric diagnosis by a clinical structured interview for Axis I disorders (SCID‐I) and personality disorders (SCID‐II), Clinical Global Impression (CGI), and Quality of Life (SF‐36).ResultsAnorexia nervosa, restrictive type, was diagnosed in 73.9% of the patients and 51% of the patients presented with comorbidity on Axis I or Axis II or both. The predictive variables for the PCS were poor outcome in previous year, comorbidity on Axes I and II, and female gender. The predictive variables for the MCS were the presence of comorbidity in one or the other of the Axis I or II disorders and purging behaviors.DiscussionThe current study suggests the importance of comorbidity and purging behaviors in the quality of life of these patients with anorexia nervosa. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 445–450, 2004.
Dissonance thin‐ideal and didactic healthy behavior eating disorder prevention programs: Results from a controlled trial
Authors: Matusek Jill Anne , Wendt Sally J. , Wiseman Claire V. 
Published: November 2004

AbstractObjectiveNegative body image, a common problem among college‐age women in the United States, strongly correlates with low self‐esteem, disturbed eating behavior, and eating disorders. Psychoeducational programs have inconsistently shown improvement in body image, thin‐ideal internalization, eating behaviors, psychosocial functioning, and self‐esteem.MethodIn the current study, college women with body image concerns (N = 84) were randomly assigned to a cognitive dissonance‐based, thin‐ideal internalization, single‐session workshop (DTI; n = 26); a psychoeducational, healthy behavior, single‐session workshop (HB; n = 24); or a wait‐list control (WL; n = 34).ResultsComparing baseline data with 4‐week follow‐up data, results indicated that both DTI and HB participants reported improvement in body image, thin‐ideal internalization, and eating behaviors.DiscussionResults provide evidence that both interventions effectively reduce risk factors for eating pathology. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 376–388, 2004.
Carbene Complexes of Nonmetals
Authors: Kirmse Wolfgang 
Published: November 2004

AbstractElectrophilic carbenes accept a variety of n‐ and π‐donors. The products range from persistent ylides to matrix‐isolated xenon complexes. Ylides can be viewed as carbene complexes if they regenerate carbenesthermallyor undergoconcertedmethylene transfer reactions. According to these definitions, the present review focuses on oxonium and iodonium ylides. Transient π‐complexes appear to be involved in addition reactions of carbenes with arenes (but not with alkenes). Nucleophilic carbenes form adducts with Lewis acids which are, for the most part, stable and have been well characterized structurally. Only recently attention has been directed to reversible systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Total Synthesis and Olfactory Evaluation of 5β,10‐Dimethyl‐des‐A‐18‐nor‐androstan‐13β‐ol: A Potential Human Pheromone?
Authors: Kraft Philip , Popaj Kasim 
Published: November 2004

Abstract5β,10‐Dimethyl‐des‐A‐18‐nor‐androstan‐13β‐ol (Limdrostanol, 11) was suspected to be the underlying parent steroid responsible for the interesting urinous‐animalic, woody olfactory properties of the commercial odorant Timberol® (6−9), and the captives Norlimbanol® (7) and Limbanol® (10), and so could constitute a potential human pheromone. We report the first synthesis of 11, starting with treatment of the bis‐Grignard reagent of 1,4‐dibromobutane (15) with γ‐butyrolactone (16), Appel−Lee bromination of the resulting diol 17 with elimination of the tertiary hydroxy group, and transformation of the obtained bromo alkene 18 into the corresponding triphenylphosphonium salt 13. This was subjected to a Schlosser−Wittig reaction with the γ,δ‐unsaturated aldehyde 14, prepared in turn by Grignard treatment of ethyl methacrylate (19) and subsequent Saucy−Marbet reaction of the resulting dimethyl carbinol 20 with ethyl vinyl ether (21). Cascade cyclization of the Schlosser−Wittig product 23 with methanesulfonic acid in dichloromethane at 0 °C afforded the tricyclic alkene 24, which was transformed into the target structure 11 by epoxidation with 3‐chloroperbenzoic acid and subsequent reduction with lithium triethylborohydride. In addition to 11, the corresponding 14α‐isomer 26 was obtained, and the olfactory properties of both are discussed. The high odor thresholds of 11 and 26, as well as the distinct differences in odor with 6−10, make it very unlikely that these des‐A‐18‐nor‐androstanols are the underlying odorous principle of 6−10, or that they function as human pheromones. An alternative synthesis of 11 by cyclization of 23 at 0 °C with 0.8 equivalents of methanesulfonic acid in formic acid as terminating nucleophile is also discussed, but gave only unsatisfactory yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Pulsed Amperometric Detection of Histamine at Glassy Carbon Electrodes Modified with Gold Nanoparticles
Authors: Carralero V. , González‐Cortés A. , Yáñez‐Sedeño P. , Pingarrón J. M. 
Published: November 2004

AbstractGold nanocrystal‐modified glassy carbon electrodes (nAu‐GCE) were prepared and used for the determination of histamine by flow injection and high performance liquid chromatography using pulsed amperometric detection (PAD) as the detection mode. Experimental variables involved in the electrodeposition process of gold from a HAuCl4 solution were optimized. A catalytic enhancement of the histamine voltammetric response was observed at the nAu‐GCE when compared with that obtained at a conventional Au disk electrode, as a consequence of the microdispersion of gold nanocrystals on the GC substrate. The morphological and electrochemical characteristics of the nAu‐GCE were evaluated by SEM and cyclic voltammetry. PAD using a very simple potential waveform consisting of an anodic potential (+700 mV for 500 ms) and a cathodic potential (−300 mV for 30 ms), was used to avoid the electrode surface fouling when histamine was detected under flowing conditions. Flow injection amperometric responses showed much higher Ip values and signal‐to‐noise ratios at the nAu‐GCE than at a conventional gold disk electrode. A limit of detection of 6×10−7 mol L−1 histamine was obtained. HPLC‐PAD at the nAu‐GCE was used for the determination of histamine in the presence of other biogenic amines and indole. Histamine was determined in sardine samples spiked at a 50 μg g−1 concentration level, with good results. Furthermore, the chromatographic PAD method was also used for monitoring the formation of histamine during the decomposition process of sardine samples.
Amperometric Sensors Based on Synthetic Hydrotalcites and Their Application for Ethanol Detection in Beer
Authors: Scavetta Erika , Tonelli Domenica 
Published: November 2004

AbstractThe electrochemical and electrocatalytic behavior of electrodes modified with a Co/Al‐NO3 hydrotalcite (HT) has been investigated and compared with that displayed by Ni/Al‐NO3 HT modified electrodes. Mono and polyhydric compounds have been tested to study electrocatalysis. At Co/Al‐NO3 HT modified electrodes only polyhydric compounds give e current signal, whereas at Ni/Al‐NO3 HT modified electrodes, both alcohols and polyhydric compounds can be detected. The different electrocatalytic behavior of Ni and Co based electrodes has been exploited to develop an analytic method for the selective determination of alcohols in the presence of polyhydric compounds. Samples of beer found on the Italian market have been analyzed to verify the validity of the proposed method in the detection of the ethanol content. The procedure does require neither a preliminar treatment nor a separation of the sample, but only the recording of two cyclic voltammogramms, one with the Co/Al‐NO3 and one with the Ni/Al‐NO3 HT modified electrode. The results obtained have been promising.
Characterization and Electrocatalytic Properties of Composite Poly(new fuchsin) and Phosphomolybdate Films
Authors: Chen Shen‐Ming , Fa Yu‐Hsiang 
Published: November 2004

AbstractOrganic/inorganic hybrid films of poly(new fuchsin) and phosphomolybdate (PMo12O$\rm{ {_{40}^{3-}}}$) have been prepared in acidic aqueous solutions. These new combination films are stable, electrochemically active, and can be produced on glassy carbon, platinum, gold, and transparent semiconductor tin oxide electrodes. An electrochemical quartz crystal microbalance along with cyclic voltammetry and UV‐visible absorption spectroscopy were used to study the in situ growth of the hybrid films. The hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films showed four obvious redox couples, and when transferred to various acidic aqueous solutions, the formal potentials of the four redox couples were found to be pH dependent. The electrocatalytic reduction of ClO$\rm{ {_{3}^{-}}}$, BrO$\rm{ {_{3}^{-}}}$, IO$\rm{ {_{3}^{-}}}$, SO$\rm{ {_{5}^{2{-}}}}$, S2O$\rm{ {_{8}^{{{2-}}}}}$, H2O2, and NO$\rm{ {_{2}^{-}}}$ by the hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films was achieved in acidic aqueous solutions. In an aqueous solution at pH 1.5, a hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ film showed a higher electrocatalytic reduction activity of IO$\rm{ {_{3}^{-}}}$ than BrO$\rm{ {_{3}^{-}}}$ or ClO$\rm{ {_{3}^{-}}}$, and the order of electrocatalytic activity was IO$\rm{ {_{3}^{-}}}$>BrO$\rm{ {_{3}^{-}}}$>ClO$\rm{ {_{3}^{-}}}$. The order of electrocatalytic reduction of SO$\rm{ {_{5}^{{{2-}}}}}$, S2O$\rm{ {_{8}^{{{2-}}}}}$, H2O2, and NO$\rm{ {_{2}^{-}}}$ by hybrid poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films in an aqueous solution at pH 1.5 was NO$\rm{ {_{2}^{-}}}$>H2O2>S2O$\rm{ {_{8}^{{{2-}}}}}$ and SO$\rm{ {_{5}^{{{2-}}}}}$. The electrocatalytic reactions of the poly(new fuchsin) and PMo12O$\rm{ {_{40}^{3-}}}$ films were investigated using the rotating ring‐disk electrode method.
Carbon‐Nanotube Based Electrochemical Biosensors: A Review
Authors: Wang Joseph 
Published: November 2004

AbstractThis review addresses recent advances in carbon‐nanotubes (CNT) based electrochemical biosensors. The unique chemical and physical properties of CNT have paved the way to new and improved sensing devices, in general, and electrochemical biosensors, in particular. CNT‐based electrochemical transducers offer substantial improvements in the performance of amperometric enzyme electrodes, immunosensors and nucleic‐acid sensing devices. The greatly enhanced electrochemical reactivity of hydrogen peroxide and NADH at CNT‐modified electrodes makes these nanomaterials extremely attractive for numerous oxidase‐ and dehydrogenase‐based amperometric biosensors. Aligned CNT “forests” can act as molecular wires to allow efficient electron transfer between the underlying electrode and the redox centers of enzymes. Bioaffinity devices utilizing enzyme tags can greatly benefit from the enhanced response of the biocatalytic‐reaction product at the CNT transducer and from CNT amplification platforms carrying multiple tags. Common designs of CNT‐based biosensors are discussed, along with practical examples of such devices. The successful realization of CNT‐based biosensors requires proper control of their chemical and physical properties, as well as their functionalization and surface immobilization.
Multiwall Carbon Nanotube (MWCNT) Based Electrochemical Biosensors for Mediatorless Detection of Putrescine
Authors: Luong John H. T. , Hrapovic Sabahudin , Wang Dashan 
Published: November 2004

Abstractγ‐Aminopropyltriethoxysilane (APTES)‐induced solubilization of multi‐wall carbon nanotube CNTs allowed for the modification of electrode surfaces. APTES also served as an immobilization matrix for putrescine oxidase (POx) to construct an amperometric biosensor. Although CNTs modified by APTES acted as semiconductors to reduce the exposed sensing surface, we reasoned that nanoscale “dendrites” of CNTS modified by APTES formed a network and projected outwards from the electrode surface and acted like bundled ultra‐microelectrodes that allowed access to the active site and facilitated direct electron transfer to the immobilized enzyme. Our biosensor was able to efficiently monitor direct electroactivity of POx at the electrode surface. The putrescine biosensor prepared using the modified glassy carbon electrode exhibited current response within 10 s with a detection limit of 500 nM.
Determination of Phenolic Compounds Based on the Tyrosinase‐ Single Walled Carbon Nanotubes Sensor
Authors: Zhao Qiang , Guan Lunhui , Gu Zhennan , Zhuang Qiankun 
Published: November 2004

AbstractAn amperometric sensor to phenolic compound was successfully constructed by immobilizing tyrosinase on the SWNTs modified glassy carbon (GC) electrode, which was covered with Nafion film. The sensitivity of the tyrosinase‐SWNTs sensor to phenol was 155 μA/mM. The tyrosinase‐SWNTs sensor also had good response to catechol, p‐chlorophenol and m‐cresol. Furthermore, benzoic acid could be detected based on the inhibition to tyrosinase activity.
Application of six‐phase soil heating technology for groundwater remediation
Authors: Smart Jimmy L. 
Published: November 2004

AbstractA treatability study for implementation of a thermally enhanced environmental remediation technique has recently been completed at a Department of Energy uranium enrichment facility in Paducah, KY. The contaminated groundwater plume beneath the site, containing primarily trichloroethylene (TCE) and technetium‐99, is one of the largest‐ever documented plumes, encompassing some quarter of a billion m3 of contaminated water (10 billion gal). Various remediation technologies have been applied at the plant site over the past 15 years with moderate degrees of success. The presence of dense nonaqueous phase liquids (DNAPLs) in the groundwater are believed to be one of the major sources of TCE feeding the contaminated plume. Recovery/remediation of these DNAPLs was attempted in a small‐scale study with a soil‐heating technique called six‐phase soil heating. This technology uses buried resistive heating probes to heat the soil and associated liquids upward to 125° C to literally vaporize the TCE solvent. Vacuum recovery wells are used to direct solvent/water vapor flow to the surface for recovery. At the end of the test period, soil and groundwater samples were compared to baseline (pretreatment) samples. This comparison indicated an average TCE concentration reduction in soil of 98% and greater than 99% reduction in TCE concentrations in groundwater within the test cell. Two‐ and 4‐week posttreatment groundwater samples within the test cell have shown a slight fluctuating increase from end‐of‐test results, but all samples collected at various well depths indicate greater than 98% reduction in TCE concentration. Monitoring well data indicates six‐phase soil heating technology was effective in extracting solvent DNAPLs rather than merely relocating them. Results of this treatability study were judged to be favorable and a full‐scale implementation at the site has been recommended. © 2004 American Institute of Chemical Engineers Environ Prog, 2004