bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of water on inorganic acids doped polyaniline
Authors: Ayad Mohamad M. , Zaki Eman. A.
Published: June 2009

Based on gravimetric measurements, the effect of water on thin films of inorganic acids doped polyaniline (PANI) was developed. The starting point was the fact that PANI coating on the electrode of quartz crystal microbalances (QCM) showed significant frequency shifts under exposure to liquid water. The changes in the frequency as a function of treatment time in water were quantitatively measured. These changes suggested that the mass decreases under water exposure were due to dopant ions release. The data have been collected using doped PANI films with HCl, H2SO4, and H3PO4. For PANI‐HCl upon immersion in water showed rapid mass loss followed by slow kinetically dopant ions release with time. However, PANI‐H3PO4 and PANI‐H2SO4 showed a slow kinetically release out of the film immediately upon immersion in water. The release process was well described by Fickian diffusion process. The diffusion coefficients (D) were determined and found to be dependent on the acid dopant utilized. They varied within the range of (1.68–14.7) × 10‐14 cm2/s. This work presented an attempt to find a simple method based on the QCM for investigating the diffusion of dopant ions out of thin PANI films upon immersion in water and determining D. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of dynamic shear on the microcellular foaming of polypropylene/high‐density polyethylene blends
Authors: Zhang Ping , Wang Xiao‐Jun , Yang Yong , Zhou Nanqiao
Published: June 2009

Dynamic shear in the axial direction of a rotor was vertically superposed on the melt flow direction, and its effects on the shear rate and melt strength were investigated theoretically. Polypropylene/high‐density polyethylene blends were microcellularly foamed with different vibration parameters. The experimental results were compared with those of a theoretical analysis, and the effects of dynamic shear on the foamability and ultimate cell structure were analyzed in detail. The theoretical results showed that the shear rate and melt strength increased with an increase in the vibration amplitude and frequency. The enhanced melt strength could effectively restrict cell growth, prevent cell rupture, and improve foamability. The experimental results showed that the cell orientation decreased and the cell structure was improved when axial dynamic shear induced by rotor vibrations was superposed on the melt flow direction. Furthermore, the cell diameter decreased and the cell density increased with increases in the vibration amplitude and frequency. The experimental results were very consistent with the theoretical analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthetic tannins structure by MALDI‐TOF mass spectroscopy
Authors: Giovando S. , Pizzi A. , Pasch H. , Rode K.
Published: June 2009

The structure, polymeric nature, and oligomers distribution of six types of commercial synthetic tannins (syntans) were determined by MALDI‐TOF mass spectrometry. The syntans examined were: (i) polycondensation oligomers of sulfonated phenol and 4,4′‐dioxydiphenylsulfone with formaldehyde and sodium bisulfite; (ii) sodium salts of polycondensation oligomers of phenol and sulfonated phenol with formaldehyde and urea; (iii) sodium salts of polycondensation oligomers of sulfonated phenol with formaldehyde and urea; (iv) sodium and ammonium salts of polycondensation oligomers of sulfonated naphtalene with formaldehyde; and (v) a sulfonated phenolic novolak resin. The oligomers distribution indicated that the relative abundance of oligomers from trimer to higher degrees of polymerization varied from 70% to more than 90% according to the different syntans tested. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Cure kinetics and thermal properties of tetramethylbiphenyl epoxy resin/phthalazinone‐containing diamine/hexa(phenoxy)cyclotriphophazene system
Authors: Zhang Xinghong , Zhou Boxuan , Sun Xueke , Qi Guorong
Published: June 2009

Inherently flame retardant epoxy resin is a kind of halogen‐free material for making high‐performance electronic materials. This work describes an inherently flame retardant epoxy system composed of 4,4′‐diglycidyl (3,3′,5,5′‐tetramethylbiphenyl) epoxy resin (TMBP), 1,2‐dihydro‐2‐(4‐aminophenyl)‐4‐(4‐(4‐aminophenoxy) phenyl) (2H) phthalazin‐1‐one (DAP), and hexa(phenoxy) cyclotriphophazene (HPCTP). The cure kinetics of TMBP/DAP in the presence or absence of HPCTP were investigated using isoconversional method by means of nonisothermal differential scanning calorimeter (DSC). Kinetic analysis results indicated that the effective activation energy (Eα) decreased with increasing the extent of conversion (α) for TMBP/DAP system because diffusion‐controlled reaction dominated the curing reaction gradually in the later cure stage. TMBP/DAP/HPCTP(10 wt %) system had higher Eα values than those of TMBP/DAP system in the early cure stage (α < 0.35), and an increase phenomenon of Eα ∼ α dependence in the later cure stage (α ≥ 0.60) due to kinetic‐controlled reaction in the later cure stage. Such complex Eα ∼ α dependence of TMBP/DAP/HPCTP(10 wt %) system might be associated with the change of the physical state (mainly viscosity) of the curing system due to the introduction of HPCTP. These cured epoxy resins had very high glass transition temperatures (202–235°C), excellent thermal stability with high 5 wt % decomposition temperatures (>340°C) and high char yields (>25.6 wt %). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Structural test of precast polymer concrete
Authors: Ahn Namshik , Park Do Kyong , Lee Jaehong , Lee Myung Kue
Published: June 2009

This study was performed to check the feasibility of concrete polymer manhole through a development test of high strength polymer concrete and prepare fundamental data for design to solve the problems of the existing cement concrete manhole. The lower absorption capacity (0.39%) of polymer concrete will be more advantageous in installing manhole in an area with subsurface water. Also long working‐life (63 minutes) will be enough to establish manholes. Conclusively, the high strength polymer concrete that is the most important issue in development of polymer concrete manhole could be made. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Chemical sensing materials II: Electrically conductive peroxide crosslinked SEBS copolymers systems
Authors: Pavlovsky S. , Siegmann A.
Published: June 2009

Chemical sensing materials based on electrically conductive styrene–ethylene butylene–styrene (SEBS) triblock‐copolymers systems were investigated. Systems based on crosslinked rather than thermoplastic SEBS systems can be exposed to a wide range of chemical environments. Composites of SEBS containing various amounts of CB and Varox DBPH (peroxide crosslinking agent) were prepared by blending at relative low temperatures, limiting the peroxide activation, and then compression molding at elevated temperatures. Samples containing CB at a level near the corresponding percolation threshold were used for the sensing experiments. Structure characterization included crosslink level and density, dynamic mechanical analysis (DMA), and calorimetry (DSC). The crosslinked SEBS composites exhibit large reversible changes in conductivity on exposure to various solvents and air drying cycles The observed electrical conductivity changes on solvent sorption/desorption is based on the polymer reversible swelling, resulting in breakdown and reconstruction of conductive CB networks, respectively. Sensing performance depends mainly on the solvents solubility parameter and volatility. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Fluid flow modeling in a sulfonated cation‐exchange membrane
Authors: Villaluenga Juan P. G. , Barragán V. María , Izquierdo–Gil M. Amparo , Godino M. Paz , Seoane Benjamin , Ruiz–Bauzá Carlos
Published: June 2009

Liquid permeation measurements of water, methanol, and 2‐propanol were carried out using a commercial cation‐exchange membrane Nafion‐117 (perfluorinated polyethylene with pendant ether‐linked side chains terminated with sulfonated groups). The experimental permeation data are treated and analyzed using the capillary model, leading to the determination of equivalent pore radius of the membrane structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Conformationally Constrained Analogs of N‐Substituted Piperazinylquinolones: Synthesis and Antibacterial Activity of N‐(2,3‐Dihydro‐4‐hydroxyimino‐4H‐1‐benzopyran‐3‐yl)‐piperazinylquinolones
Authors: Emami Saeed , Foroumadi Alireza , Samadi Nasrin , Faramarzi Mohammad A. , Rajabalian Saeed
Published: June 2009

A series of novel quinolone agents bearing a particular bulky and conformationally constrained bicyclic substituent (2,3‐dihydro‐4‐hydroxyimino‐4H‐1‐benzopyran‐3‐yl‐ moiety) on the piperazine ring of 7‐piperazinyl quinolones (norfloxacin, enoxacin, ciprofloxacin, and levofloxacin) were synthesized and evaluated against a panel of Gram‐positive and Gram‐negative bacteria. Among these derivatives, ciprofloxacin counterpart 9c, highly inhibited the tested Gram‐positive bacteria, superior to that of the reference drugs, and displayed antibacterial activity at non‐cytotoxic concentrations.
Discovery and Potency Optimization of 2‐Amino‐5‐arylmethyl‐1,3‐thiazole Derivatives as Potential Therapeutic Agents for Prostate Cancer
Authors: Krasavin Mikhail , Karapetian Ruben , Konstantinov Igor , Gezentsvey Yuri , Bukhryakov Konstantin , Godovykh Elena , Soldatkina Olga , Lavrovsky Yan , Sosnov Andrei V. , Gakh Andrei A.
Published: June 2009

A new chemical series was identified via high‐throughput screening as having antiproliferative activity on DU‐145 human prostate carcinoma cell line (hit compound potency – 2.9 μM). Medicinal chemistry optimization of two peripheral diversity vectors of the hit molecule, independently, led to SAR generalizations and identification of the ‘best’ moieties. The latter were merged in a single compound that exhibited an over 100‐fold better potency than the hit compound. For the most potent compounds it was confirmed that the observed antiproliferative potency was not associated with the compounds' non‐specific cytotoxicity.
Image indexing in article component databases
Authors: Gelernter Judith
Published: June 2009

It is often necessary to compare data‐rich charts, tables, diagrams, or drawings rather than the articles that contextualize that data. The objective of this research has been to create a database of non‐textual components (here, maps) that are searchable independently of the articles from which they are taken, with the option to view the source articles. The method mines words from the articles that are near or associated with each component map, and these mined words become the basis of region, time, and subject indexing. The evaluation showed that automatic indexing of the component maps by these three facets works well, and indicates that a large‐scale component database following this model is viable.
Fractionalized counting of publications for the g‐Index
Authors: Schreiber Michael
Published: June 2009

L. Egghe (2008) studied the h‐index (Hirsch index) and the g‐index, counting the authorship of cited articles in a fractional way. But his definition of the gF‐index for the case that the article count is fractionalized yielded values that were close to or even larger than the original g‐index. Here I propose an alternative definition by which the g‐index is modified in such a way that the resulting gm‐index is always smaller than the original g‐index. Based on the interpretation of the g‐index as the highest number of articles of a scientist that received on average g or more citations, in the specification of the new gm‐index the articles are counted fractionally not only for the rank but also for the average.
The behaviors of metal ions in the CdTe quantum dots–H2O2 chemiluminescence reaction and its sensing application
Authors: Sheng Zonghai , Han Heyou , Liang Jiangong
Published: June 2009

The behaviors of 15 kinds of metal ions in the thiol‐capped CdTe quantum dots (QDs)–H2O2 chemiluminescence (CL) reaction were investigated in detail. The results showed that Ag+, Cu2+ and Hg2+ could inhibit CdTe QDs and H2O2 CL reaction. A novel CL method for the selective determination of Ag+, Cu2+ and Hg2+ was developed, based on their inhibition of the reaction of CdTe QDs and H2O2. Under the optimal conditions, good linear relationships were realized between the CL intensity and the logarithm of concentrations of Ag+, Cu2+ and Hg2+. The linear ranges were from 2.0 × 10−6 to 5.0 × 10−8 mol L−1 for Ag+, from 5.0 × 10−6 to 7.0 × 10−8 mol L−1 for Cu2+ and from 2.0 × 10−5 to 1.0 × 10−7 mol L−1 for Hg2+, respectively. The limits of detection (S/N = 3) were 3.0 × 10−8, 4.0 × 10−8 and 6.7 × 10−8 mol L−1 for Ag+, Cu2+ and Hg2+, respectively. A possible mechanism for the inhibition of CdTe QDs and H2O2 CL reaction was also discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Effects of the grafting on the fluorescence properties of CdTe nanocrystals
Authors: Mei Fang , He Xi‐Wen , Li Wen‐You , Zhang Yu‐Kui
Published: June 2009

In this paper, we systematically investigated the influence of graft reagents having an amino or a carboxyl terminus with different chain lengths on the fluorescence properties of water‐soluble thioglycolic acid‐stabilized CdTe nanocrystals (TGA–CdTe). Strong enhancement effects of the grafting on the fluorescence intensity of TGA–CdTe were observed. The experiment results demonstrated that short‐chain‐length grafting can increase the fluorescence intensity of CdTe nanocrystals (NCs) better than long‐chain‐length grafting, and the grafting did not influence the emission wavelength of the CdTe NCs. The fluorescence intensity of the carboxyl‐grafted TGA–CdTe was more stable than that of the amino‐grafted TGA–CdTe at wide pH ranges (pH 5.1–10.0). Copyright © 2009 John Wiley & Sons, Ltd.
Automated determination of asulam by enhanced chemiluminescence using luminol/peroxidase system
Authors: Sánchez Francisco García , Díaz Aurora Navas , Bracho Visitación , Aguilar Alfonso , Algarra Manuel
Published: June 2009

A flow injection system with chemiluminescence detection for the determination of asulam, enhancer of the system luminol–H2O2–horseradish peroxidase, is proposed. The method shows a moderate selectivity against other pesticides usually present in formulations of herbicides and in water. The procedure was applied to the determination of asulam in tap water samples and a recovery study was carried out in order to validate the method. The obtained results show acceptable recovery values (between 88.3 and 93.9%). The detection limit for asulam was 0.12 ng/mL. The precision of the method expressed as relative standard deviation was 1.55% (n = 8), at the 19 ng/mL level. Copyright © 2009 John Wiley & Sons, Ltd.
The petrosal nerves: Anatomy, pathology, and surgical considerations
Authors: Tubbs R. Shane , Menendez Joshua , Loukas Marios , Shoja Mohammadali M. , Shokouhi Ghaffar , Salter E. George , Cohen‐Gadol Aaron
Published: June 2009

The literature lacks a comprehensive review of the petrosal nerves, which often have a complicated course and nomenclature. The medical literature was reviewed comprehensively for information regarding the anatomy, pathology, and surgery of the petrosal nerves. The terminology and anatomy of the petrosal nerves are often complicated. Our review found multiple nomenclatures used in the description of these structures. Information regarding the petrosal nerves may assist those who observe or operate at or near the skull base. To our knowledge, this is the first comprehensive review of these structures. Clin. Anat. 22:537–544, 2009. © 2009 Wiley‐Liss, Inc.
In vivo and in vitro morphometry of the human trachea
Authors: Kamel Kirollos Salah , Lau Gabriel , Stringer Mark D.
Published: June 2009

Most morphometric studies of the human trachea have relied on plain radiographs with their attendant limitations. Reports using computed tomography (CT) have focused on the growing trachea or one particular dimension. The aim of this study was to document the morphometry of the adult trachea in vivo using high‐resolution chest CT scans, supplemented by data from cadavers. Sixty anonymised high‐resolution chest CT scans (aged 22–88 years, 40 males) were analyzed. Scans were performed using a standardized breath‐holding technique in patients with no distorting intrathoracic pathology. Standardized tracheal measurements included: length, maximum antero‐posterior and transverse diameters, volume, subcarinal angle, and carinal position in relation to the tracheal midline. Measurements were also made in 10 cadaver tracheas (aged 68–101 years, 7 males). CT data showed that mean tracheal length (males 105.1 ± 9.8 mm, females 98.3 ± 8.7 mm), maximum antero‐posterior and transverse diameters, and tracheal volume (males 35.6 ± 6.8 cm3, females 24.7 ± 6.1 cm3) were all significantly greater in men (P ≤ 0.01). The subcarinal angle was very variable (mean 78 ± 20°, range 36–121°) and showed no correlation with age or gender. The carina was sited to the left of the tracheal midline in 49 (81%) patients. Cadaver tracheas had 14–19 tracheal rings and the posterior membranous trachea was wider in men (17.7 ± 4.4 mm vs. 11.8 ± 3.0 mm, P = 0.07). In conclusion, there is marked sexual dimorphism in the morphometry of the human trachea. The variation in adult tracheal dimensions in vivo is greater than in standard descriptions. These data may be valuable when interpreting chest CT scans and when calculating respiratory dead space. Clin. Anat. 22:571–579, 2009. © 2009 Wiley‐Liss, Inc.
Anatomical considerations for natural orifice translumenal endoscopic surgery
Authors: Moran Erica A. , Gostout Christopher J.
Published: June 2009

Success in surgical procedures relies on the surgeon's understanding of anatomy and the ways in which the internal organs relate to one another. Recently, a new surgical technique has been introduced. Natural orifice translumenal endoscopic surgery (NOTES) uses the body's natural orifices (mouth, anus, urethra, or vagina) as entrance points to the peritoneal cavities (through the stomach, rectum, bladder, or posterior vaginal fornix). NOTES techniques have proven feasible in both animal and early human trials. While it remains to be seen what advantages NOTES possesses over traditional surgical approaches, a clear understanding of human anatomy will be critical for successful, safe NOTES procedures. This article summarizes the development and the basic techniques of NOTES and reviews those anatomical considerations specific to NOTES. Clin. Anat. 22:627–632, 2009. © 2009 Wiley‐Liss, Inc.
Inguinal canal development: The muscular wall and the role of the gubernaculum
Authors: Biasutto Susana N. , Repetto Emanuel , Aliendo Mirta M. , Borghino Valeria N.
Published: June 2009

The inguinal canal is an anatomically complex region. Although much has been written about the gubernaculum and the descent of the testis, little is known about the development of the abdominal wall itself. We dissected this inguinal canal in 75 fetuses between 10 and 25 weeks of gestation, 42 males and 33 females. We identified the anterior body‐wall muscular layers, located the gonads and uterus, and observed the formation of the scrotum. The gubernaculum was dissected, from the deep to the superficial ends and its distal attachments were determined. We proved that the muscular‐fibrous layers of the wall were well‐differentiated and observed how the inguinal canal enlarged with embryological development. In only one of the cases, an abnormal testis was found located in the scrotum. The upper end of the gubernaculum inserted into the inferior pole of the testis or the lateral angle of the uterus, according to gender. The lower end was attached by one or multiple tails, mainly on the pubic bone. This fact explained the clinical findings of ectopic testis. Observations of the abdominal wall and its relationship with the gubernaculum assisted us in explaining the development of the inguinal region, the formation of the inguinal canal, and the presence of the gubernaculum, in both genders. We intend to explain how the deep inguinal ring moves upwards, bringing the gubernaculum along with it, and thus determines the final form of the inguinal canal. Clin. Anat. 22:614–618, 2009. © 2009 Wiley‐Liss, Inc.
Steric Constraints Dependent on Nucleobase Pair Orientation Vary in Different DNA Polymerase Active Sites
Authors: Streckenbach Frank , Rangam Gopinath , Möller Heiko M. , Marx Andreas
Published: June 2009

Finding the right fit: Herein, we report on the development of novel steric probes and present initial insights into their interplay with DNA polymerases. Our findings provide experimental evidence for varied enzyme–substrate interactions that might account for the varied selectivity previously observed.

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Coordination Chemistry: New Routes to Mesostructured Materials
Authors: Roy Xavier , MacLachlan Mark J.
Published: June 2009

Merging of two structures: A strategy to develop micro–mesoporous materials using coordination chemistry is discussed and the concept is illustrated with the formation of mesostructured Prussian blue analogues. Through liquid‐crystal templating, new routes to metal–organic microporous frameworks with simultaneous mesoporosity are discussed.

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Although micro‐ and mesoporous materials have each been extensively studied separately, very little work has been done to combine both porosity ranges into a single material. Materials with bimodal porosity could have attractive properties for a wide range of applications and could open new areas of study. Here, we present a strategy to develop micro–mesoporous materials using coordination chemistry, and illustrate the concept with the formation of mesostructured Prussian blue analogues.
Synthesis and in vitro sodium channel blocking activity evaluation of novel homochiral mexiletine analogs
Authors: Carocci Alessia , Catalano Alessia , Bruno Claudio , Lentini Giovanni , Franchini Carlo , De Bellis Michela , De Luca Annamaria , Conte Camerino Diana
Published: June 2009

New chiral mexiletine analogs were synthesized in their optically active forms and evaluated in vitro as use‐dependent blockers of skeletal muscle sodium channels. Tests carried out on sodium currents of single muscle fibers ofRana esculentademonstrated that all of them exerted a higher use‐dependent block than mexiletine. The most potent analog, (S)‐3‐(2,6‐dimethylphenoxy)‐1‐phenylpropan‐1‐amine (S)‐(5), was six‐fold more potent than (R)‐Mex in producing a tonic block. As observed with mexiletine, the newly synthesized compounds exhibit modest enantioselective behavior, that is more evident in 3‐(2,6‐dimethylphenoxy)butan‐1‐amine (3). Chirality, 2010. © 2009 Wiley‐Liss, Inc.
Following the lipase catalyzed enantioselective hydrolysis of amino acid esters with capillary electrophoresis using contactless conductivity detection
Authors: Schuchert‐Shi Aiping , Hauser Peter C.
Published: June 2009

The progress of the enzymatic hydrolysis of racemic mixtures of the enantiomers of the methyl esters of serine and threonine was monitored. This was possible in a reaction vessel of 1.5 mL by direct sampling of volumes in the nanoliter‐range directly into an electrophoresis capillary. Contactless conductivity detection was used for quantification as the analytes are not accessible by UV‐detection in capillary electrophoresis. Porcine pancreatic lipase and wheat germ lipase both showed a preference for the L‐enantiomers of both amino acid esters. The selectivity of the porcine lipase between the two L‐esters of the two amino acids was also studied and it was found that the production of L‐threonine had priority over L‐serine. Chirality, 2010. © 2009 Wiley‐Liss, Inc.
Vibrational Raman optical activity of 1‐phenylethanol and 1‐phenylethylamine: Revisiting old friends
Authors: Kapitán Josef , Johannessen Christian , Bouř Petr , Hecht Lutz , Barron Laurence D.
Published: June 2009

The samples used for the first observations of vibrational Raman optical activity (ROA) in 1972, namely both enantiomers of 1‐phenylethanol and 1‐phenylethylamine, have been revisited using a modern commercial ROA instrument together with state‐of‐the‐art ab initio calculations. The simulated ROA spectra reveal for the first time the vibrational origins of the first reported ROA signals, which comprised similar couplets in the alcohol and amine in the spectral range ∼280–400 cm−1. The results demonstrate how easy and routine ROA measurements have become, and how current ab initio quantum–chemical calculations are capable of simulating experimental ROA spectra quite closely provided sufficient averaging over accessible conformations is included. Assignment of absolute configuration is, inter alia, completely secure from results of this quality. Anharmonic corrections provided small improvements in the simulated Raman and ROA spectra. The importance of conformational averaging emphasized by this and previous related work provides the underlying theoretical background to ROA studies of dynamic aspects of chiral molecular and biomolecular structure and behavior. Chirality 21:E4–E12, 2009. © 2009 Wiley‐Liss, Inc.
Enantioselective addition of phenylacetylene to aldehydes catalyzed by polymer‐supported titanium(IV) complexes of β‐hydroxy amides
Authors: Hui Xin‐Ping , Huang Lu‐Ning , Li Ya‐Min , Wang Ren‐Lin , Xu Peng‐Fei
Published: June 2009

A series of polymer‐supported chiral β‐hydroxy amides and C2‐symmetric β‐hydroxy amides have been synthesized and successfully used for the enantioselective addition of phenylacetylene to aldehydes. High yields (up to 93%) and enantioselectivities (up to 92% ee) were achieved by using polymer‐supported chiral β‐hydroxy amide 4b. The resin 4b is reused four times, giving the product with enantioselectivity 80% ee. Fortunately, it is found that this heterogonous system is suitable not only for aromatic aldehydes but also aliphatic aldehyde. Chirality, 2010. © 2009 Wiley‐Liss, Inc.
Study on the stereoselective excretion of tetrahydropalmatine enantiomers in rats and identification of in vivo metabolites by liquid chromatography‐tandem mass spectrometry
Authors: Hong Zhanying , Wen Jun , Zhang Quanlong , Fan Guorong , Chai Yifeng , Wu Yutian
Published: June 2009

The objective of this work was to study the stereoselectivity in excretion of tetrahydropalmatine (THP) enantiomers by rats and identify the metabolites of racemic THP (rac‐THP) in rat urine. Urine and bile samples were collected at various time intervals after a single oral dose of rac‐THP. The concentrations of THP enantiomers in rat urine and bile were determined using a modification of an achiral–chiral high‐performance liquid chromatographic (HPLC) method that had been previously published. The cumulative urinary excretion over 96 h of (−)‐THP and (+)‐THP was found to be 55.49 ± 36.9 μg and 18.33 ± 9.7 μg, respectively. The cumulative biliary excretion over 24 h of (−)‐THP and (+)‐THP was 19.19 ± 14.6 μg and 12.53 ± 10.4 μg, respectively. The enantiomeric (−/+) concentration ratios of THP changed from 2.80 to 5.15 in urine, and from 1.36 to 1.80 in bile. The mean cumulative amount of (−)‐THP was significantly higher than that of (+)‐THP both in urine and bile samples. However, the enantiomeric (−/+) concentration ratios in rat urine and bile were significantly lower than those ratios in rat plasma. These findings suggested the excretion of THP enantiomers was stereoselective rather than a reflection of chiral pharmacokinetic aspects in plasma and (−)‐THP was preferentially excreted in rat urine and bile. Three O‐demethylation metabolites and the parent drug rac‐THP were detected by liquid chromatography‐tandem mass spectrometry in rat urine. One metabolite was obtained by preparative HPLC and identified as 10‐O‐demethyl‐THP. Chirality, 2010. © 2009 Wiley‐Liss, Inc.
Flussmittel‐kalzinierte Kieselguren: Effekt der Flussmittel‐Kationengröße auf die Phaseneigenschaften
Authors: Smejkal Q. , Schleicher T. , Ruß W. , Martin A.
Published: June 2009

Die Größe des Kations (Li, Na, K, Cs) eines Carbonat‐Flussmittels hat Einfluss auf die Qualität einer kalzinierten Kieselgur. Bei den Untersuchungen stand besonders die Vermeidung der Bildung von kristallinem Cristobalit im Vordergrund. Die gezielte Kalzination unter extremen Kalzinationsbedingungen, nämlich hoher Temperatur, langer Verweilzeit und kleiner Temperaturrampe führte zu signifikanten Änderungen der Partikeloberfläche. Neben der erwünschten Sinterung bzw. Porenverschluss wies die zunächst amorphe Struktur der Kieselgur nach der Kalzination in Abhängigkeit vom verwendeten Flussmittel kristalline Oberflächenbereiche (Cristobalit) auf. Während Li2CO3 bzw. Na2CO3 als Flussmittel zu hohen Cristobalitanteilen führten, zeigte die Cs2CO3 Modifikation nahezu keine Cristobalitbildung. Die Verwendung von K2CO3 nimmt eine Mittelstellung ein. Phasenänderungen und Oberflächenvorgänge wurden mittels Pulverdiffraktometrie (XRD) und Transmissionselektronenmikroskopie (TEM) verfolgt. Die erhaltenen Ergebnisse zeigen, dass für eine weitere Untersuchung im industriellen Maßstab besonders Kaliumcarbonat als geeignet erscheint.
Experimentelle Untersuchung der katalytischen Partialoxidation von Modellkraftstoffen unter definierten Randbedingungen
Authors: Hartmann M. , Deutschmann O. , Lichtenberg S. , Hebben N. , Zhang D.
Published: June 2009

Mit Rhodium beschichtete Katalysatoren ermöglichen durch katalytische Partialoxidation (CPOX) die Darstellung großer Mengen Wasserstoff aus höheren Kohlenwasserstoffen wie Benzin oder Diesel innerhalb weniger Millisekunden Kontaktzeit. Die Reaktionsenthalpie erzeugt Temperaturen von bis zu 1300 °C und erlaubt den autothermen Betrieb von kompakten CPOX Reaktoren in Fahrzeugen, die einen neuen Weg zur Versorgung von APUs (auxiliary power unit) mit Wasserstoff bzw. Synthesegas aus bereits bestehenden Versorgungsnetzen aufzeigen. Zur Evaluierung von Modellen und der Aufklärung wichtiger Einzelprozesse der Reaktion wurde eine Versuchsanlage entwickelt, an der die katalytische Partialoxidation von Modellkraftstoffen unter definierten Randbedingungen erforscht werden kann. Dabei realisiert die Verwendung kombinierter Messverfahren (Prozess‐Infrarot‐Spektrometerie, Sektorfeld‐Massenspektrometerie, paramagnetische Sauerstoffdetektion) die zeitaufgelöste Untersuchung der Reaktionsprodukte mit geschlossenen Bilanzen bei allen technisch relevanten Betriebspunkten. Eine detaillierte Analyse der Kohlenwasserstoffe erfolgt mit Hilfe eines Gaschromatographen. Beispielhaft werden Selektivität und Umsatz für die CPOX von i‐Oktan im stationären wie instationären Betrieb diskutiert.
Biogene Kraftstoffe – Potenziale und Grenzen
Authors: Schöne H. , gen. Klaas M. Rüsch
Published: June 2009

Kohlenwasserstoffe haben als Kraftstoffe große Vorteile, aber ihre Produktion aus Biomasse terrestrischer Pflanzen stößt an ökonomische und ökologische Grenzen. Landwirtschaftliche Anbaubiomasse kann bei heutigem Verbrauch nur einen begrenzten Beitrag zur Kraftstoffversorgung leisten. Das Potenzial landwirtschaftlicher Abfälle ist zu erschließen. Biokraftstoffe sollten dort eingesetzt werden, wo sie ökologische Vorteile besitzen, z. B. wegen ihrer geringen Wassergefährdung als Bootskraftstoffe.
Potenzialermittlung eines modifizierten Festbett‐Rohrreaktors
Authors: Wollmann A. , Benker B. , Keich O. , Bank R.
Published: June 2009

Um das wirtschaftliche Potenzial eines modifizierten Rohreaktors zu ermitteln, wurde ein zweidimensionales Modell für Wärmeaustausch und Reaktion entwickelt. Die Modellparameter wurden in Versuchen mit dem konventionell betriebenem Reaktor bestimmt. Rechnung und Versuch zeigen übereinstimmend eine wesentliche Absenkung der hot spot‐Temperatur bei der „Rohr‐in‐Rohr”︁‐Betriebsweise.
Graded actin filament polarity is the organization of oriented actomyosin II filament bundles required for fibroblast polarization
Authors: Mseka Tayamika , Coughlin Margaret , Cramer Louise P.
Published: June 2009

Actomyosin II filament assemblies in cells are required for shaping the cell body and forming the cell rear during morphological polarization and triggering of migration. However, precise steps in myosin II‐based mechanisms are unknown in this event; one reason is due to lack of information on the organization of the actin filament substrate for myosin II. Whilst muscle sarcomeric‐like contraction drives cell tension in stationary nonmuscle cells, alternative nonsarcomeric modes of myosin II force‐generation power forwards movement of the cell body in already migrating cells. Which one contributes to initial cell shape change has not previously been experimentally sought in any polarizing cell. Sarcomeric and nonsarcomeric‐based force require completely different types of organization and filament polarity in the actin substrate for myosin II, and these can only currently be distinguished by labour‐intensive submicron analysis and electron microscopy. For the first time in any polarizing cell using such analysis we have identified that oriented actomyosin II filament bundles, required for fibroblast polarization, are nonsarcomeric and are organized with graded filament polarity. As this actin organization is similar to the organization in already migrating fibroblasts, we conclude that graded filament polarity is a pivotal myosin II substrate coordinating initial cell shape change and triggering of migration. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
Connexins, cell motility, and the cytoskeleton
Authors: Olk Stephan , Zoidl Georg , Dermietzel Rolf
Published: June 2009

Connexins (Cx) comprise a family of transmembrane proteins, which form intercellular channels between plasma membranes of two adjoining cells, commonly known as gap junctions. Recent reports revealed that Cx proteins interact with diverse cellular components to form a multiprotein complex, which has been termed “Nexus”. Potential interaction partners include proteins such as cytoskeletal proteins, scaffolding proteins, protein kinases and phosphatases. These interactions allow correct subcellular localization of Cxs and functional regulation of gap junction‐mediated intercellular communication. Evidence is accruing that Cxs might have channel‐independent functions, which potentially include regulation of cell migration, cell polarization and growth control. In the current review, we summarize recent knowledge on Cx interactions with cytoskeletal proteins and highlight some aspects of their role in cellular motility. Cell Motil. Cytoskeleton 66: 1000–1016, 2009. © 2009 Wiley‐Liss, Inc.
Induced‐Fit Docking Approach Provides Insight into the Binding Mode and Mechanism of Action of HIV‐1 Integrase Inhibitors
Authors: Barreca Maria Letizia , Iraci Nunzio , De Luca Laura , Chimirri Alba
Published: June 2009

A three‐dimensional model of a complex between HIV‐1 integrase (IN), viral DNA, and metal ions that we recently built was used as a target for a docking method (induced‐fit docking, IFD) that accurately predicts ligand binding modes and concomitant structural changes in the receptor. Six different well‐known integrase strand transfer inhibitors (INSTIs): L‐708,906, L‐731,988, S‐1360, L‐870,810, raltegravir, and elvitegravir were thus used as ligands for our docking simulations. The obtained IFD results are consistent with the mechanism of action proposed for this class of IN inhibitors, that is, metal chelating/binding agents. This study affords new insight into the possible mechanism of inhibition and binding conformations for INSTIs. The impact on our hypothesis of specific mutations associated with IN inhibitor resistance was also evaluated. All these findings might have implications for integrase‐directed HIV‐1 drug discovery efforts.
Building Quick Service Query list (QSQL) to support automated service discovery for scientific workflow
Authors: Ren Kaijun , Chen Jinjun , Xiao Nong , Song Junqiang
Published: June 2009

Scientific workflow is emerging as a promising scientific computing paradigm to offer the convenience for the scientists to resolve complex scientific problems. To successfully execute a scientific workflow, the workflow creation by depending on service discovery techniques should be made in the first place. Particularly, semantics have been proposed as a key to automatically solve service discovery issue for facilitating users to create a workflow. However, most of the semantic service discovery methods still remain at a low‐efficiency stage because they generally involve a large number of ontology reasoning that is often time consuming. To address this issue, we present an efficient service discovery method by building Quick Service Query list (QSQL) to support automated service discovery for creating a workflow. QSQL based on graph storage theory is an efficient service index list that is dynamically built by service publication algorithm. In QSQL, semantic relationships between the published services and all related ontology concepts can be processed in advance so that a large number of ontology reasoning can be avoided during service discovery. Further, our proposed discovery algorithm can efficiently select service models from QSQL to match a user query. The final experiments further demonstrate the feasibility and the efficiency of our proposed method. Copyright © 2009 John Wiley & Sons, Ltd.
A template‐free route for controlled synthesis of dumbbell‐like Sb2S3 microcrystals
Authors: Xu Yongbin , Ren Zhongming , Cao Guanghui , Ren Weili , Deng Kang , Zhong Yunbo
Published: June 2009

Large amounts of dumbbell‐like Sb2S3 microcrystals were synthesized via a simple solvothermal treatment method. Various techniques such as x‐ray diffraction (XRD), field‐emission scanning electron microscope (FESEM), high‐resolution transmission electron microscope (HRTEM), selected area electron diffraction (SAED), and photoluminescence spectrometry (PL) have been used to characterize the obtained products. The results showed that the products belong to the orthorhombic Sb2S3 phase, and the dumbbell‐like Sb2S3 microcrystals were composed by uniform microrods. Besides, the morphologies of Sb2S3 microcrystals could be changed from microshperes to dumbbell‐like microcrystals by only adjusting the reaction solvent. The solvent effects are discussed in detail. Furthermore, the PL properties of the obtained Sb2S3 microcrystals clearly show shape effects. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ultrasound assisted crystallization for the recovery of lactose in an anti‐solvent acetone
Authors: Patel S. R. , Murthy Z. V. P
Published: June 2009

Continuous worldwide increase in high‐scale production of dairy products leads to the constant generation of vast amounts of liquid by‐product, whey. Disposal of liquid whey is costly due to its high biological oxygen demand (BOD) and water content. More than 90% of whey BOD is due to lactose. Recovery of lactose from whey solves both the problems of improving economics of whey utilization and pollution reduction as lactose recovery itself can reduce BOD of whey by more then 80%. Commercial effluent treatment techniques focus on degradation rather than recovery of useful by‐products like lactose. Also, these techniques are time consuming and hence not effective enough. Sonocrystallization is the use of power ultrasound to control the crystallization process during the nucleation phase. In the present study, the process of lactose crystallization has been studied for the recovery of lactose from reconstituted lactose solutions with the aid of ultrasound, in the presence of ‘acetone’, as an anti‐solvent. The crystallization is found to be completed with excellent yields in the range of 80 – 92% within 4 minutes of sonication. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
One‐step synthesis of ZnO/MgO core‐sheath structures
Authors: Wei Xiaoqun , Li Haichao , Chen Shuixia , Yuan Chane , Yuan Qingyu
Published: June 2009

A kind of ZnO/MgO core‐sheath structure has been prepared directly by the pyrolysis of a mixture of polyvinyl alcohol, magnesium acetate, and zinc chloride coating on glass fiber mats at 450 °C for 60 min. The growing process and effect of the anions on the morphology of ZnO/MgO structures have been preliminarily discussed. The results indicate that ZnCl2 will transform to ZnO crystal through an intermediate of zinc hydroxide chloride. ZnO crystal act as the core of the micorod, and MgO lamellas act as the sheath. The concurrence of chloride and acetate anions in the precursor is necessary for the growth of ZnO/MgO core‐sheath structures. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Flux growth and low temperature dielectric relaxation in piezoelectric Pb[(Zn1/3Nb2/3)0.91Ti0.09]O3 single crystals
Authors: Singh B. K. , Kumar K. , Sinha N. , Kumar B.
Published: June 2009

Single crystals of Pb[(Zn1/3Nb2/3)0.91Ti0.09]O3 (PZNT 91/9) have been grown by flux method after modifications in temperature profile, flux ratio and addition of excess ZnO/B2O3 which resulted in enhanced perovskite yield (more than 95%). Only a few crystals showed the presence of pyrochlore phase/variation in composition. A comparative characterization of these crystals were carried out in respect of piezoelectric charge coefficient d33, dielectric constant, ac conductivity and hysteresis loop after cutting and poling the crystals along [001] direction. The total activation energy for conduction has been found to increase with Ti‐content in the sample. The effect of ZnO on growth behavior has been analyzed. A detailed analysis of PZNT (91:9) has been carried out at low temperature in respect of the various thermodynamic parameters related to the dielectric relaxation mechanism, like optical dielectric constant, static dielectric constant, free energy of activation for dipole relaxation, enthalpy of activation and relaxation time, have been calculated in the vicinity of transition temperature in the lower temperature region. The activation energy for relaxation at ‐10 and ‐49 °C have been found to be 0.09 and 0.02 eV respectively. The results were analyzed and a detailed dielectric analysis and low temperature relaxation behavior of PZNT crystals were interpreted. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simple extraction‐solvothermal synthesis of single‐crystalline silver microplates
Authors: You Ting , Sun Sixiu , Song Xinyu , Xu Shuling
Published: June 2009

Single‐crystalline silver microplates, with average edge length of about 1.5 μm and thickness of 100 nm, have been synthesized by a simple extraction‐solvothermal method. Samples were characterized in detail by X‐ray diffraction (XRD), field‐emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM) and High‐resolution transmission electron microscopy (HRTEM) technologies. Extractant primary amine N1923 can also act as reducing agent. It has been found that microstructure of the silver can be controlled by the n‐octanol during the solvothermal treatment. Based on a series of experimental analysis, the possible formation mechanism of these microplates was discussed briefly. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Joint power, subcarrier and subframe allocation in Multihop relay networks
Authors: Girici Tolga
Published: June 2009

In this paper we study the problem of subframe, subchannel and power allocation in OFDMA‐based multihop relay networks. The system consists of a base station (BS), a number of relay stations (RS) and mobile stations (MS). We consider frame by frame scheduling, where the frame is divided into two subframes such as BS‐RS and RS‐MS subframes. We study two different problems, satisfying link rate requirements with minimum‐weighted total power and maximizing proportional fairness. For the first problem, we find the optimal solution and also propose a less complex subframe and bandwidth allocation scheme with good performance. For the second problem, we propose an algorithm that outperforms an existing scheme with less feedback. Copyright © 2009 John Wiley & Sons, Ltd.
Variable expression of Dkc1 mutations in mice
Authors: He Jun , Gu Bai‐wei , Ge Jingping , Mochizuki Yuko , Bessler Monica , Mason Philip J.
Published: June 2009

In humans mutations in DKC1, cause the rare bone marrow failure syndrome dyskeratosis congenita. We have used gene targeting to produce mouse ES cells with Dkc1 mutations that cause DC when in humans. The mutation A353V, the most common human mutation, causes typical DC to very severe DC in humans. Male chimeric mice carrying this mutation do not pass the mutated allele to their offspring. The mutation G402E accounts for a single typical case of DC in a human family. The allele carrying this mutation was transmitted to the offspring with high efficiency. Expression of RNA and protein was reduced compared to wild type animals, but no abnormalities of growth and development or in blood values were found in mutant mice. Thus Dkc1 mutations have variable expression inmice, as in humans. genesis 47:366–373, 2009. © 2009 Wiley‐Liss, Inc.
An essential gene mutagenesis screen across the highly conserved piebald deletion region of mouse chromosome 14
Authors: Hagarman James A. , O'Brien Timothy P.
Published: June 2009

The piebald deletion complex is a set of overlapping chromosomal deficiencies on distal mouse chromosome 14. We surveyed the functional genetic content of the piebald deletion region in an essential gene mutagenesis screen of 952 genomes to recover seven lethal mutants. The ENU‐induced mutations were mapped to define genetic intervals using the piebald deletion panel. Lethal mutations included loci required for establishment of the left‐right embryonic axis and a loss‐of‐function allele of Phr1 resulting in respiratory distress at birth. A functional map of the piebald region integrates experimental genetic data from the deletion panel, mutagenesis screen, and the targeted disruption of specific genes. A comparison of several genomic intervals targeted in regional mutagenesis screens suggests that the piebald region is characterized by a low gene density and high essential gene density with a distinct genomic content and organization that supports complex regulatory interactions and promotes evolutionary stability. genesis 47:392–403, 2009. © 2009 Wiley‐Liss, Inc.
Role for hedgehog pathway in regulating growth and function of invariant NKT cells
Authors: Syn Wing‐Kin , Witek Rafal P. , Curbishley Stuart M. , Jung Youngmi , Choi Steve S. , Enrich Barbara , Omenetti Alessia , Agboola Kolade M. , Fearing Caitlin M. , Tilg Herbert , Adams David H. , Diehl Anna Mae
Published: June 2009

Lymphocyte accumulation is characteristic of chronic hepatitis, but the mechanisms regulating lymphocyte numbers and their roles in liver disease progression are poorly understood. The Hedgehog (Hh) pathway regulates thymic development and lymphopoeisis during embryogenesis, and is activated in fibrosing liver disease in adults. Our objective was to determine if Hh ligands regulate the viability and phenotype of NKT cells, which comprise a substantial sub‐population of resident lymphocytes in healthy adult livers and often accumulate during liver fibrosis. The results demonstrate that a mouse invariant NKT cell line (DN32 iNKT cells), mouse primary liver iNKT cells, and human peripheral blood iNKT cells are all responsive to sonic hedgehog (Shh). In cultured iNKT cells, Shh enhances proliferation, inhibits apoptosis, induces activation, and stimulates expression of the pro‐fibrogenic cytokine, IL‐13. Livers of transgenic mice with an overly active Hh pathway harbor increased numbers of iNKT cells. iNKT cells also express Shh. These results demonstrate that iNKT cells produce and respond to Hh ligands, and that Hh pathway activation regulates the size and cytokine production of liver iNKT cell populations. Therefore, Hh pathway activation may contribute to the local expansion of pro‐fibrogenic iNKT cell populations during certain types of fibrosing liver damage.