bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modified Tafel Equation for Electroless Metal Deposition
Authors: Gorker Lev , Dimitrov Vasili 
Published: June 2009

The concept of the Dynamic Electrical Double Layer (DEDL) is the physicochemical basis for electrochemical processes that proceed without an external source of current (electroless processes). The most characteristic feature of such processes is that they proceed only in an oscillation regime, with the anodic processes of electrode charging and the cathodic processes of its discharging alternating periodically at maximum values of the stationary electrode potential (the phenomenon of overpotential). The DEDL model enables full account to be taken of this specific feature (adsorption and a heterogeneous chemical reaction at the anodic stage of the process and subsequent deposition of the metal in the cathodic stage) and the process to be described from a unified standpoint. In the framework of the DEDL model, the autocatalytic process of metal coating deposition depending on process conditions is described by modified Nernst or Tafel equations, which enable direct computation of both the values of the oscillating stationary electrode potential and of the characteristics of metal deposition (thickness and weight of the coating) by the kinetic dependence of “electrode potential vs time”. It is demonstrated that both the modified Tafel equation for exchange current density (oscillation regime of the stationary electrode potential in electroless processes) and its classical interpretation for systems with constant values of the stationary electrode potential are particular cases of the Volmer – Butler equation.
Dual‐Tone Patterned Mesoporous Silicate Films Templated From Chemically Amplified Block Copolymers
Authors: Nagarajan Sivakumar , Russell Thomas P. , Watkins James J. 
Published: June 2009

AbstractDirectly patterned mesoporous silicate films are prepared using positive‐ and negative‐tone strategies by performing phase selective silica condensation within lithographically exposed poly(styrene‐b‐tert‐butyl acrylate) (PS‐b‐PtbA) templates containing photoacid generators. The use of supercritical fluid as a process medium enables rapid diffusion of the silicate precursor within the prepatterned block copolymer template film without disrupting its morphology. Template exposure through the mask triggers area selective generation of acid, which in turn both deprotects the poly(tert‐butyl acrylate) block to yield a poly(acrylic acid) block and provides a catalyst for silica precursor condensation yielding pattern formation at the device level. Because the acid generated in the UV exposed field preferentially segregates into hydrophilic poly(acrylic acid) domains of the phase segregated, deprotected block copolymer, precursor condensation is simultaneously controlled at nanoscopic length scales via templating by the underlying block copolymer morphology. The ability of PS‐b‐PtbA to undergo chemical transformation in two stages, deprotection followed by crosslinking, enables precise replications of the photomask in positive and negative tones. Detemplating via calcination yields patterned mesoporous silicate films without etching. Template formulations are optimized using infrared spectroscopic studies and the silicate films are characterized using electron microscopy and scanning force microscopy.
Ionically Conducting Two‐Dimensional Heterostructures
Authors: Guo Xiangxin , Maier Joachim 
Published: June 2009

AbstractIn the context of revealing interfacial effects on ion conduction, thin films are extremely worthwhile due to defined geometry. Of particular interest are heterostructures as they offer symmetric boundary conditions and a high density of hetero‐interfaces. The recent progress in this field is reviewed. Materials classes under concern include halides and oxides, and refer to various degrees of disorder and different mobilities. Even though in its infancy, the field of ionic heterostructures is already characterized by a variety of results of fundamental importance and of technological relevance.
UV‐grafted gradient surface polyurethane membrane
Authors: Zhao Peizhong , Hua Xingyan , Wang Yuansheng , Zhu Jinhua , Niu Fei 
Published: June 2009

AbstractGradient surfaces of polyurethane (PU) membranes were created by UV grafting approach in a graded temperature field. Acrylic acid was selected as grafting monomer to improve the hydrophilicity of the surfaces. The Fourier transform infrared spectroscope (FTIR) spectra and scanning electronic microscope (SEM) were used to characterize the gradient. The results showed that the graft yield increased gradually from the lower temperature end to the higher temperature end. As a result, the hydrophilicity of the gradient surfaces displayed a gradual change along the same direction. Water contact angle measurements also proved this point. The graft reaction rate was investigated as a function of positions along the PU membrane. The average grafting yield of PU membrane increased with the extending of UV light irradiation and increase of photo initiator dosage. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Development of a poloxamer analogs/bioadhesive polymers‐based in situ gelling ophthalmic delivery system for tiopronin
Authors: Jiang Tong‐Ying , Sun Chang‐Shan , Shen Xue , Wang Tian‐Yi , Wang Si‐Ling 
Published: June 2009

AbstractThe purpose of this study was to develop a poloxamer analogs/bioadhesive polymers‐based in situ gelling ophthalmic delivery system aiming at enhancing bioavailability and anticataract effect. The effect of poloxamer 407 (P407), poloxamer 188 (P188), carbopol 934P (C934), and sodium hyaluronate (NaHA) concentration on the gelation temperature (GT) was examined. The GT of P407 based in situ gel increased with an increase in the P188 concentration. NaHA and C934 lowered the GT of poloxamer analogs based in situ gel. Correlation analysis demonstrated that in vitro drug release from in situ gel was controlled by gel dissolution and followed zero‐order kinetics. Tiopronin in vitro transcorneal transit accorded with zero‐order kinetics. Twenty‐two percent P407 and 6% P188 containing 0.2% NaHA based formulation can be chosen as in situ gel matrix of tiopronin because of proper GT and sustained releasing ability. In vivo study showed that the area under the aqueous humor–concentration time curve of tiopronin increased by 1.6 folds for in situ gel, compared with tiopronin aqueous solution. High‐dose tiopronin in situ gel and solution delayed the development of selenite cataract 6 d and 4 d, respectively. The results showed that tiopronin in situ gel exhibits higher bioavailability and therapeutical effect. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Parallel Synthesis of O‐Phenoxyethyl and O‐Adamantyl N‐acyl Thiocarbamates Endowed with Antiproliferative Activity
Authors: Spallarossa Andrea , Cesarini Sara , Schenone Silvia , Ranise Angelo 
Published: June 2009

AbstractIn order to further explore the antiproliferative properties of O‐phenoxyethyl and O‐adamantyl acylthiocarbamates (ATCs), a series of 14 derivatives was prepared by a parallel adaptation of a highly convergent one‐pot three‐step procedure. Ten acylthiocarbamates were selected by the National Cancer Institute drug evaluation program and screened against a panel of 55 to 58 cell lines derived from nine different types of human cancers. In general, the tested compounds showed a widespread micromolar activity with some specificity against leukemia, renal UO‐31, central nervous system (CNS) SNB‐75, and non‐small cell lung HOP‐92 cancer cell lines. Bioinformatic COMPARE analyses were carried out to identify possible mechanism(s) of action for acylthiocarbamate antiproliferative activity.
Ontologies in knowledge management support: A case study
Authors: Almeida Mauricio Barcellos , Barbosa Ricardo Rodrigues 
Published: June 2009

AbstractInformation and knowledge are true assets in modern organizations. In order to cope with the need to manage these assets, corporations have invested in a set of practices that are conventionally called knowledge management. This article presents a case study on the development and the evaluation of ontologies that was conducted within the scope of a knowledge management project undertaken by the second largest Brazilian energy utility. Ontologies have different applications and can be used in knowledge management, in information retrieval, and in information systems, to mention but a few. Within the information systems realm, ontologies are generally used as system models, but their usage has not been restricted to software development. We advocate that, once assessed as to its content, an ontology may provide benefits to corporate communication and, therefore, provide support to knowledge management initiatives. We expect to further contribute by describing possibilities for the application of ontologies within organizational environments.
Hilfsmittel für die Vorbemessung von Stahlbetonkonsolen
Authors: Schwitzke Marko 
Published: June 2009

AbstractIn diesem Beitrag werden Nomogramme für die Vorbemessung von Stahlbetonkonsolen vorgestellt. Basierend auf den entsprechenden Bemessungsvorschriften kann für eine gegebene Beanspruchung die erforderliche statische Höhe einer Stahlbetonkonsole bestimmt werden. Die Anwendung der Nomogramme wird anhand eines Beispiels erläutert.
Development and validation of a sensitive assay for the quantification of imatinib using LC/LC‐MS/MS in human whole blood and cell culture
Authors: Klawitter Jelena , Zhang Yan Ling , Klawitter Jost , Anderson Nora , Serkova Natalie J. , Christians Uwe 
Published: June 2009

AbstractWe developed and validated a semi‐automated LC/LC‐MS/MS assay for the quantification of imatinib in human whole blood and leukemia cells. After protein precipitation, samples were injected into the HPLC system and trapped onto the enrichment column (flow 5 mL/min); extracts were back‐flushed onto the analytical column. Ion transitions [M + H]+of imatinib (m/z = 494.3 → 394.3) and its internal standard trazodone (372.5 → 176.3) were monitored. The range of reliable response was 0.03–75 ng/mL. The inter‐day precisions were: 8.4% (0.03 ng/mL), 7.2% (0.1 ng/mL), 6.5% (1 ng/mL), 8.2% (10 ng/mL) and 4.3% (75 ng/mL) with no interference from ion suppression. Autosampler stability was 24 hs and samples were stable over three freeze–thaw cycles. This semi‐automated method is simple with only one manual step, uses a commercially available internal standard, and has proven to be robust in larger studies. Copyright © 2009 John Wiley & Sons, Ltd.
Rapid high‐performance liquid chromatography–tandem mass spectrometry method for simultaneous measurement of venlafaxine and O‐desmethylvenlafaxine in human plasma and its application in comparative bioavailability study
Authors: Rajasekhar D. , Kumar I. Jaswanth , Venkateswarlu P. 
Published: June 2009

AbstractA rapid high‐performance liquid chromatography–tandem mass spectrometry method has been developed and validated for simultaneous measurement of venlafaxine and O‐desmethylvenlafaxine in human plasma using fluoxetine as an internal standard. In the liquid–liquid extraction method, compounds and internal standard were extracted from plasma using methyl tertiary butyl ether as an extraction solvent. The HPLC separation of the analytes was performed on a Zorbax SB‐C18, 50 × 4.6 mm, 5 µm column, using a isocratic elution program using a mobile phase consisting of HPLC‐grade methanol: 5 mm ammonium acetate (80:20 v/v) at a flow‐rate of 1.0 mL/min with a total runtime of 3.0 min. The proposed method has been validated with a linear range of 4–400 ng/mL for venlafaxine and 5–500 ng/mL for O‐desmethyl venlafaxine. The method was applied for a bio‐equivalence study of 75 mg tablets formulation in 32 Indian male healthy subjects under fasting conditions. Copyright © 2009 John Wiley & Sons, Ltd.
Analysis of the constituents in rat plasma after oral administration of Shexiang Baoxin pill by HPLC‐ESI‐MS/MS
Authors: Jiang Peng , Liu Ruihui , Dou Shengshan , Liu Lei , Zhang Weidong , Chen Zhongliang , Xu Ruilin , Ding Jianmi 
Published: June 2009

AbstractA valid method using liquid chromatography coupled with electrospray ionization (ESI) and ion trap mass spectrometry was established for the study of the absorbed components in rat plasma after oral administration of a traditional Chinese medicine (TCM) Shexiang Baoxin pill. The plasma was deproteinated by adding methanol prior to liquid chromatography, in which separation was carried out on a Symmetry C18 column (5 µm, 250 × 4.6 mm). A linear gradient with 0.5% formic acid–water–acetonitrile was used as mobile phase. Mass spectra were acquired in both negative and positive modes. Twenty‐one components including 17 components from Shexiang Baoxin pill and four metabolites were observed from a comprehensive analysis of the chromatography of Shexiang Baoxin pill, controlled plasma and dosed plasma. All of the 17 prototype compounds and three of the metabolites were identified by comparing their retention behaviors and MS and MS/MS spectra with reference compounds and literature data. This study developed an integrated method for screening the bioactive constituents in plasma after oral adminstration of Chinese herbal medicine and provided helpful chemical information for further pharmacology and active mechanism research on TCM. Copyright © 2009 John Wiley & Sons, Ltd.
Rapid and specific high‐performance liquid chromatography for the in vitro quantification of d‐Lys6–GnRH in a microemulsion‐type formulation in the presence of peptide oxidation products
Authors: Kafka Alexandra P. , Rades Thomas , McDowell Arlene 
Published: June 2009

AbstractA high‐performance liquid chromatography (HPLC) method for assay of d‐Lys6–GnRH contained in a microemulsion‐type formulation is described. The peptide is extracted from the microemulsion matrix and quantified using a two‐step gradient method. Separation from microemulsion compounds and potential peptide oxidation products was achieved on a Jupiter C18 column at 40°C, using a gradient of 10–35% CH3CN for peptide elution. The correlation of peak intensity measured at 220 nm and peptide concentration was linear over the range 2.5–60 µg/mL with a correlation coefficient of 0.9997 and a y‐intercept not significantly different from zero (p > 0.05). Intraday and interday variability of the assay was less than 5% for multiple injections of samples containing 7.5, 30 and 60 µg/mL. The lower limit of quantitation was calculated to be 0.38 µg/mL, and the lower limit of detection was 0.13 µg/mL. The assay was applied to samples that were stressed under physiological conditions (37°C, pH 7.4) over 4 days. Three degradation peaks were well resolved from the parent peptide, demonstrating the selectivity of the assay. Off‐line MALDI TOF mass spectrometry was applied to identify these degradation species as oxidation products of the peptide. Copyright © 2009 John Wiley & Sons, Ltd.
Analysis of oxidation process of cholecystokinin octapeptide with reactive oxygen species by high‐performance liquid chromatography and subsequent electrospray ionization mass spectrometry
Authors: Ichiba Hideaki , Nakamoto Mio , Yajima Takehiko , Takayama Mitsuo , Fukushima Takeshi 
Published: June 2009

AbstractThe C‐terminal octapeptide of cholecystokinin (CCK8) includes some easily oxidizable amino acids. The oxidation of CCK8 by reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and hydroxyl radicals (OH•) was investigated using reversed‐phase high performance liquid chromatography (RP‐HPLC) and subsequent electrospray ionization mass spectrometry. The mechanism of oxidation of CCK8 in the H2O2 system differed from that of CCK8 in the Fenton system, in which OH• are produced. In the H2O2 system, 28Met and 31Met were oxidized to methionine sulfoxide, and no further oxidation or degradation/hydrolysis occurred. On the other hand, in the Fenton system, 28Met and 31Met residues were oxidized to methionine sulfone via the formation of methionine sulfoxide. In addition, the oxidized product was observed at the Trp residue but not at the Tyr residue, and small peptide fragments from CCK8 were observed in the Fenton system. From these results, it was concluded that 28Met and 31Met residues of CCK8 are susceptible to oxidation by ROS. Copyright © 2009 John Wiley & Sons, Ltd.
‘Give me a hug’: the effects of touch and autonomy on people's responses to embodied social agents
Authors: Cramer Henriette , Kemper Nicander , Amin Alia , Wielinga Bob , Evers Vanessa 
Published: June 2009

AbstractEmbodied social agents are programmed to display human‐like social behaviour to increase intuitiveness of interacting with these agents. It is yet unclear what the differences in peoples' responses are to different types of agents' social behaviours. One example is touch. Despite robots' physical embodiment and increasing autonomy, the effect of communicative touch has been a mostly overlooked aspect of human‐robot interaction. This video‐based, 2 × 2 between‐subject survey experiment (N = 119) found that the combination of touch and proactivity influenced whether people saw the robot as machine‐like and dependable. Furthermore, participants' attitude toward robots in general was found to influence perceived closeness between a human and a robot. Results show that communicative touch could be considered a more appropriate behaviour for proactive agents rather than reactive agents. Also, people that are generally more positive towards robots find robots that interact by touch less machine‐like. These effects illustrate that careful consideration is necessary when incorporating social behaviours in agents' physical interaction design. Copyright © 2009 John Wiley & Sons, Ltd.
Extracellular Biosynthesis of Gold Nanoparticles using Aspergillus niger – its Characterization and Stability
Authors: Bhambure R. , Bule M. , Shaligram N. , Kamat M. , Singhal R. 
Published: June 2009

AbstractThe development of an eco‐friendly and reliable process for the synthesis of gold nanomaterials using microorganisms is gaining importance in the field of nanotechnology. In the present study, gold nanoparticles have been synthesized by reduction of aqueous gold ions using the culture supernatant of Aspergillus niger NCIM 616. The synthesis of the gold nanoparticles was monitored by UV‐visible spectroscopy. The particles thereby obtained were characterized by UV, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X‐ray diffraction (XRD). The stability of the synthesized gold nanoparticles was analyzed by zeta potential measurement. Treatment of the fungal supernatant with aqueous Au+ ions produced nanoparticles with an average particle size of 12.79 ± 5.61 nm. Different characterization studies showed that the extracellular enzyme secreted by Aspergillus niger NCIM 616 might be responsible for both formation and capping of the metal nanoparticles.
Nichtnewtonsche schäumende Flüssigkeiten in Rieselbettreaktoren – Hydrodynamische Charakterisierung und effiziente Schaumbegrenzung
Authors: Aydin B. , Schubert M. , Lange R. , Larachi F. 
Published: June 2009

AbstractHydrodynamische Studien in Rieselbettreaktoren unter erhöhten Drücken und Temperaturen beschäftigen sich hauptsächlich mit koaleszierenden, also nichtschäumenden, Systemen. Obwohl in zahlreichen industriellen Prozessen schäumende Flüssigkeiten eingesetzt werden, ist keine aussagekräftige Datenbasis vorhanden. Für die verlässliche Auslegung und den sicheren Betrieb von Reaktoren wurden die Effekte von Temperatur und Druck auf die hydrodynamischen Kenngrößen für newtonsche und nichtnewtonsche schaumbildende Systeme untersucht. Außerdem wurde eine neue operative Methode entwickelt, bei der der Rieselbettreaktor alternierend zyklisch betrieben wird und die ohne die Dosierung von chemischen Zusätzen effektiv zur Begrenzung der Schaumbildung eingesetzt werden kann.
Overall survival of newly diagnosed glioblastoma patients receiving carmustine wafers followed by radiation and concurrent temozolomide plus rotational multiagent chemotherapy
Authors: Affronti Mary Lou , Heery Christopher R. , Herndon James E. , Rich Jeremy N. , Reardon David A. , Desjardins Annick , Vredenburgh James J. , Friedman Allan H. , Bigner Darell D. , Friedman Henry S. 
Published: June 2009

AbstractBACKGROUND:Glioblastoma multiforme (GBM), the most lethal type of brain tumor, has a 1‐year median survival. The effect of carmustine wafers on the survival of newly diagnosed GBM patients treated with radiotherapy (RT) and concurrent temozolomide (TMZ) plus RT plus rotational chemotherapy was investigated.METHODS:An institutional review board‐approved retrospective study was conducted in 85 newly diagnosed GBM patients who received surgical resection with and without carmustine wafers followed by RT and concurrent TMZ plus rotational chemotherapy. Treatment group comparisons were conducted using the log‐rank test. Survival experience of the Duke cohort was examined within specific patient subgroups defined by the original Radiation Therapy Oncology Group (RTOG) recursive partition analysis (RPA) class and compared with the European Organization for Research and Treatment of Cancer (Stupp) and RTOG trial.RESULTS:Overall 1‐ and 2‐year survival for the noncarmustine wafer cohort were 69% and 29%, respectively, with a median survival of 72.7 weeks. One‐ and 2‐year survival for the carmustine wafer cohort were 81% and 47%, with median survival of 89.5 weeks. Carmustine wafer was not an independent predictor (P = .110) of survival after adjustment for RPA class. The proportion of patients in the carmustine wafer cohort who lived longer than predicted based upon Stupp regimen results was significantly greater than 0.5 (P<.006); similar results based upon the RTOG trial data were observed (P < .001).CONCLUSIONS:Carmustine wafer with concurrent TMZ and radiation followed by rotational chemotherapy is a well tolerated, effective therapy, and has a survival benefit compared with radiation alone. Prospective randomized trials are needed to rigorously compare the carmustine wafer regimen to the Stupp and postradiation multimodality regimens. Cancer 2009. © 2009 American Cancer Society.
Lung radiofrequency ablation in patients with pulmonary metastases from musculoskeletal sarcomas
Authors: Nakamura Tomoki , Matsumine Akihiko , Yamakado Koichiro , Matsubara Takao , Takaki Haruyuki , Nakatsuka Atsuhiro , Takeda Kan , Abo Daisuke , Shimizu Tadashi , Uchida Atsumasa 
Published: June 2009

AbstractBACKGROUND:The authors retrospectively evaluated the impact of lung radiofrequency (RF) ablation on survival in patients with lung metastases from musculoskeletal sarcomas.METHODS:Lung RF ablation was done under the real‐time computed tomography (CT) fluoroscopy. Safety, local tumor progression, and survival were evaluated in 2 institutions.RESULTS:Lung RF ablation was performed in 20 consecutive patients. The mean maximum tumor diameter was 14 ± 9 mm (range, 5‐40 mm) and the mean tumor number 7 ± 6 (range, 1‐18) per patient. Pneumothorax requiring chest tube placement developed in 24 of 63 RF sessions (38%). During the mean follow‐up period of 18 months (range, 7 months to 54 months), 9 of 20 patients died of lung tumor progression. The 1‐ and 3‐year survival rates from RF ablation were 58% (95% confidence interval [CI], 33.3‐82.6%) and 29% (95% CI, 0‐59.9%) with a median survival time of 12.9 months in all patients. Ablation of all lung tumors was the only significantly better prognostic factors in both the univariate analysis and the multivariate analyses. The 1‐ and 3‐year survival rates were 88.9% (95% CI, 69.3%‐100%) and 59.2% (95% CI, 10.2%‐100%) in 11 patients with complete tumor ablation.CONCLUSIONS:Lung RF ablation is a safe and useful therapeutic option for selected patients. (R#1) Prognostic factors identified in our study will help to stratify those patients who may benefit from lung RF ablation. Cancer 2009. © 2009 American Cancer Society.