bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractThe 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

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

AbstractMerging 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.magnified imageAlthough 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

AbstractNew 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

AbstractThe 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

AbstractThe 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

AbstractA 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

AbstractThe 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

AbstractDie 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

AbstractMit 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

AbstractKohlenwasserstoffe 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

AbstractUm 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

AbstractActomyosin 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

AbstractConnexins (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

AbstractA 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

AbstractScientific 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

AbstractLarge 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

AbstractContinuous 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

AbstractA 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

AbstractSingle 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)